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two-phase parse milestone 2a: body spans + SeekTo with fidelity check (inert)

ProbeBody records each outermost body span (name + start offset) and
verifies SeekTo repositions exactly (same sym re-scanned at same
offset); both silent unless mismatched, side effects discarded by
PopPos. Suite 196/196 (gate covers both mismatch kinds); 142-file
flag-on sweep byte-identical, zero mismatches; fixpoint OK.

Also sharpens the V3 rule found on the way: no forward procedure
tolerance at all (even P declared two lines later is 233); atg
helpers need strict declaration-before-use (NoteSpan moved up).
Eric Streit 1 天之前
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dce67fcdfb
共有 5 個文件被更改,包括 3576 次插入 和 3452 次删除
  1. 1 1
      compiler/run_tests.sh
  2. 41 6
      compiler/src/M2.atg
  3. 3480 3445
      compiler/src/M2.lst
  4. 20 0
      compiler/src/scanner.frm
  5. 34 0
      docs/plan-two-phase-parse.md

+ 1 - 1
compiler/run_tests.sh

@@ -470,7 +470,7 @@ twophase_same() {
   rm -f "gen_ssa/$mod.ssa" "gen_ssa/$mod.off.ssa"
   ./M2 "tests/$name" >/dev/null 2>&1
   cp "gen_ssa/$mod.ssa" "gen_ssa/$mod.off.ssa"
-  if ./M2 -twophase "tests/$name" 2>&1 | grep -q "twophase probe mismatch"; then
+  if ./M2 -twophase "tests/$name" 2>&1 | grep -q "twophase .*mismatch"; then
     fail=$((fail+1)); echo "FAIL(twophase): $name probe mismatch"; return
   fi
   if cmp -s "gen_ssa/$mod.off.ssa" "gen_ssa/$mod.ssa"; then

+ 41 - 6
compiler/src/M2.atg

@@ -68,6 +68,14 @@ VAR
   twoPhaseParse: BOOLEAN;
   procNest: CARDINAL;
 
+  (* Two-phase parse spans (milestone 2a): one entry per outermost body
+     shadow-skipped while twoPhaseParse is on — procedure name and the
+     buffer offset its body starts at (the lookahead token's nextPos).
+     Per-parse; nothing consumes the table yet. *)
+  nSpans: CARDINAL;
+  spanName: ARRAY [0 .. 1023] OF SymTab.Name;
+  spanStart: ARRAY [0 .. 1023] OF M2S.INT32;
+
   (* Result slot for the expression-AST builder (slice 2).  Every
      Expr/SimExpr/Term/Fact leaves its node here; the combination
      productions save it into locals before parsing the next operand.
@@ -341,17 +349,33 @@ PROCEDURE Adv;
     INC(errDist)
   END Adv;
 
+PROCEDURE NoteSpan (pn: SymTab.Name; start: M2S.INT32);
+(* Records an outermost body span for the re-parse pass (milestone 2).
+   Diagnostic only for now: nothing consumes the table yet.  Declared
+   before its caller: V3 resolves single-pass (declaration before use),
+   with no forward tolerance for procedure calls. *)
+  BEGIN
+    IF nSpans > HIGH(spanName) THEN RETURN END;
+    CopyNm(pn, spanName[nSpans]);
+    spanStart[nSpans] := start;
+    INC(nSpans)
+  END NoteSpan;
+
 PROCEDURE ProbeBody (pn: SymTab.Name);
 (* Shadow-skip the body starting at the current token: consume tokens
    counting block openers until the matching END, check the procedure
-   name after it, then restore the exact scanner/parser state.  The
-   body then parses normally, so a correct skipper is output-neutral;
-   a wrong one reports to StdOut (never into the listing). *)
+   name after it, record the body span for the re-parse pass, verify
+   SeekTo repositions exactly, then restore the exact scanner/parser
+   state.  The body then parses normally, so a correct skipper is
+   output-neutral; a wrong one reports to StdOut (never into the
+   listing).  The SeekTo check's side effects are discarded by the
+   trailing PopPos, so it is output-neutral too. *)
   VAR savedSym, savedErr, depth, guard: CARDINAL;
     nm: SymTab.Name;
-    ok: BOOLEAN;
+    ok, sok: BOOLEAN;
+    start: M2S.INT32;
   BEGIN
-    savedSym := sym; savedErr := errDist;
+    savedSym := sym; savedErr := errDist; start := M2S.nextPos;
     M2S.PushPos;
     depth := 0; guard := 0; ok := TRUE;
     LOOP
@@ -374,12 +398,23 @@ PROCEDURE ProbeBody (pn: SymTab.Name);
       M2S.GetName(M2S.nextPos, M2S.nextLen, nm);
       IF (sym = 0) OR NOT SymTab.Equal(nm, pn) THEN ok := FALSE END
     END;
+    IF ok THEN NoteSpan(pn, start) END;
+    sok := TRUE;
+    IF ok THEN
+      M2S.SeekTo(start);
+      Adv;
+      IF (sym # savedSym) OR (M2S.nextPos # start) THEN sok := FALSE END
+    END;
     M2S.PopPos;
     sym := savedSym; errDist := savedErr;
     IF NOT ok THEN
       FileIO.WriteString(FileIO.StdOut, "twophase probe mismatch in ");
       FileIO.WriteString(FileIO.StdOut, pn);
       FileIO.WriteLn(FileIO.StdOut)
+    ELSIF NOT sok THEN
+      FileIO.WriteString(FileIO.StdOut, "twophase seek mismatch in ");
+      FileIO.WriteString(FileIO.StdOut, pn);
+      FileIO.WriteLn(FileIO.StdOut)
     END
   END ProbeBody;
 
@@ -415,7 +450,7 @@ PRODUCTIONS
     = (. twoPhase := TRUE; astCur := AST.NoNode; astStmt := AST.NoNode; astDecl := AST.NoNode; astImp := AST.NoNode; astImpTail := AST.NoNode;
                                            astImp := AST.NoNode;
                                            astImpTail := AST.NoNode;
-                                           procNest := 0; .)
+                                           procNest := 0; nSpans := 0; .)
       Unit "." .
   (* Units: program modules compile fully; DEFINITION and
      IMPLEMENTATION modules parse + check now but lower in step 4

+ 3480 - 3445
compiler/src/M2.lst

@@ -87,3469 +87,3504 @@ Listing:
    68    twoPhaseParse: BOOLEAN;
    69    procNest: CARDINAL;
    70  
-   71    (* Result slot for the expression-AST builder (slice 2).  Every
-   72       Expr/SimExpr/Term/Fact leaves its node here; the combination
-   73       productions save it into locals before parsing the next operand.
-   74       `astIsLit` in Fact is per-invocation, so a nested Fact cannot make
-   75       an outer non-literal Fact look literal. *)
-   76    astCur: AST.Node;
-   77  
-   78    (* Actual-argument nodes collected by ActParam for the call being
-   79       parsed by ArgList (slice 4).  Fact resets the count before the
-   80       optional ArgList and then folds the nodes into an NkCall. *)
-   81    astNArgs: CARDINAL;
-   82    astArgs: ARRAY [0 .. 31] OF AST.Node;
-   83  
-   84    (* Statement-AST result slot (slice 5): the most recently parsed
-   85       statement.  StatSeq folds these into an NkBlock. *)
-   86    astStmt: AST.Node;
-   87  
-   88    (* Declaration-AST result slot (slice 6): the most recently built
-   89       declaration; DeclSeq folds these into an NkDeclSeq. *)
-   90    astDecl: AST.Node;
+   71    (* Two-phase parse spans (milestone 2a): one entry per outermost body
+   72       shadow-skipped while twoPhaseParse is on — procedure name and the
+   73       buffer offset its body starts at (the lookahead token's nextPos).
+   74       Per-parse; nothing consumes the table yet. *)
+   75    nSpans: CARDINAL;
+   76    spanName: ARRAY [0 .. 1023] OF SymTab.Name;
+   77    spanStart: ARRAY [0 .. 1023] OF M2S.INT32;
+   78  
+   79    (* Result slot for the expression-AST builder (slice 2).  Every
+   80       Expr/SimExpr/Term/Fact leaves its node here; the combination
+   81       productions save it into locals before parsing the next operand.
+   82       `astIsLit` in Fact is per-invocation, so a nested Fact cannot make
+   83       an outer non-literal Fact look literal. *)
+   84    astCur: AST.Node;
+   85  
+   86    (* Actual-argument nodes collected by ActParam for the call being
+   87       parsed by ArgList (slice 4).  Fact resets the count before the
+   88       optional ArgList and then folds the nodes into an NkCall. *)
+   89    astNArgs: CARDINAL;
+   90    astArgs: ARRAY [0 .. 31] OF AST.Node;
    91  
-   92    (* The local declarations of the most recent Block (a procedure body);
-   93       ProcDecl stores them as the proc node's child 2. *)
-   94    astBlkDecls: AST.Node;
+   92    (* Statement-AST result slot (slice 5): the most recently parsed
+   93       statement.  StatSeq folds these into an NkBlock. *)
+   94    astStmt: AST.Node;
    95  
-   96    (* Unit-AST root (slice 7): NkUnit(name, decls, body). *)
-   97    astUnit: AST.Node;
-   98  
-   99    (* Import accumulator (slice 11): `{ Import }` appends NkImport
-  100       nodes here; each unit stores them as NkUnit child[3]. *)
-  101    astImp, astImpTail: AST.Node;
-  102  
-  103    (* Class-AST accumulators (slice 13): the class node currently being
-  104       parsed and its parent/field/method lists.  Classes are not nested
-  105       inside one another, so module-level state is safe. *)
-  106    astCls, astClsP, astClsPTail, astClsF, astClsFTail,
-  107    astClsM, astClsMTail, astMethod: AST.Node;
-  108  
-  109    (* Class of the method named by the last `obj.Method` designator
-  110       (InvalidType when the callee is an ordinary procedure). Set by
-  111       Design, consumed by the following ArgList. *)
-  112    methCls: SymTab.TypeIndex;
-  113    (* Class of the type of the innermost `TypeName{...}` brace
-  114       constructor (ClSet or ClArray); dispatches BraceElem. *)
-  115    braceCls: INTEGER;
-  116    (* Module-level VAR declarations whose type was still an unresolved
-  117       forward alias at declaration time; emitted once the TYPE block
-  118       completes (module scope only). *)
-  119    nPendVar: CARDINAL;
-  120    pendVarName: ARRAY [0 .. 255] OF SymTab.Name;
-  121    pendVarT: ARRAY [0 .. 255] OF SymTab.TypeIndex;
-  122    (* Forward module-level variables referenced from a procedure body. *)
-  123    (* GOTO/labels: the label and goto names of the procedure being parsed,
-  124       reset per procedure and checked at its END. *)
-  125    nLab, nGot: CARDINAL;
-  126    labNm, gotNm: ARRAY [0 .. 255] OF SymTab.Name;
-  127  
-  128    (* Generics (Increment 1): the last refining module seen — instance
-  129       name, generic name, and the actual type parameters. *)
-  130    refInst, refGen: SymTab.Name;
-  131    refN: CARDINAL;
-  132    refActual: ARRAY [0 .. 15] OF SymTab.TypeIndex;
-  133    isGen: BOOLEAN;
-  134  
-  135    (* Generics (Increment 2): instantiation re-parse context.  When the
-  136       driver re-parses a generic's source to instantiate it as `instName`,
-  137       instActive is TRUE, the module is renamed, and each type formal is
-  138       bound to the corresponding instActual entry. *)
-  139    instActive: BOOLEAN;
-  140    instName: SymTab.Name;
-  141    instActual: ARRAY [0 .. 15] OF SymTab.TypeIndex;
-  142    instN: CARDINAL;
-  143    instFk: CARDINAL;   (* formal cursor while binding during re-parse *)
-  144  
-  145    (* Identity of the last-parsed unit and refinement, for the driver's
-  146       generic registry and its re-parse decision. *)
-  147    unitName: SymTab.Name;
-  148    unitWasGen: BOOLEAN;
-  149    unitWasDef: BOOLEAN;
-  150    refSeen: BOOLEAN;
-  151    refIsDef: BOOLEAN;
+   96    (* Declaration-AST result slot (slice 6): the most recently built
+   97       declaration; DeclSeq folds these into an NkDeclSeq. *)
+   98    astDecl: AST.Node;
+   99  
+  100    (* The local declarations of the most recent Block (a procedure body);
+  101       ProcDecl stores them as the proc node's child 2. *)
+  102    astBlkDecls: AST.Node;
+  103  
+  104    (* Unit-AST root (slice 7): NkUnit(name, decls, body). *)
+  105    astUnit: AST.Node;
+  106  
+  107    (* Import accumulator (slice 11): `{ Import }` appends NkImport
+  108       nodes here; each unit stores them as NkUnit child[3]. *)
+  109    astImp, astImpTail: AST.Node;
+  110  
+  111    (* Class-AST accumulators (slice 13): the class node currently being
+  112       parsed and its parent/field/method lists.  Classes are not nested
+  113       inside one another, so module-level state is safe. *)
+  114    astCls, astClsP, astClsPTail, astClsF, astClsFTail,
+  115    astClsM, astClsMTail, astMethod: AST.Node;
+  116  
+  117    (* Class of the method named by the last `obj.Method` designator
+  118       (InvalidType when the callee is an ordinary procedure). Set by
+  119       Design, consumed by the following ArgList. *)
+  120    methCls: SymTab.TypeIndex;
+  121    (* Class of the type of the innermost `TypeName{...}` brace
+  122       constructor (ClSet or ClArray); dispatches BraceElem. *)
+  123    braceCls: INTEGER;
+  124    (* Module-level VAR declarations whose type was still an unresolved
+  125       forward alias at declaration time; emitted once the TYPE block
+  126       completes (module scope only). *)
+  127    nPendVar: CARDINAL;
+  128    pendVarName: ARRAY [0 .. 255] OF SymTab.Name;
+  129    pendVarT: ARRAY [0 .. 255] OF SymTab.TypeIndex;
+  130    (* Forward module-level variables referenced from a procedure body. *)
+  131    (* GOTO/labels: the label and goto names of the procedure being parsed,
+  132       reset per procedure and checked at its END. *)
+  133    nLab, nGot: CARDINAL;
+  134    labNm, gotNm: ARRAY [0 .. 255] OF SymTab.Name;
+  135  
+  136    (* Generics (Increment 1): the last refining module seen — instance
+  137       name, generic name, and the actual type parameters. *)
+  138    refInst, refGen: SymTab.Name;
+  139    refN: CARDINAL;
+  140    refActual: ARRAY [0 .. 15] OF SymTab.TypeIndex;
+  141    isGen: BOOLEAN;
+  142  
+  143    (* Generics (Increment 2): instantiation re-parse context.  When the
+  144       driver re-parses a generic's source to instantiate it as `instName`,
+  145       instActive is TRUE, the module is renamed, and each type formal is
+  146       bound to the corresponding instActual entry. *)
+  147    instActive: BOOLEAN;
+  148    instName: SymTab.Name;
+  149    instActual: ARRAY [0 .. 15] OF SymTab.TypeIndex;
+  150    instN: CARDINAL;
+  151    instFk: CARDINAL;   (* formal cursor while binding during re-parse *)
   152  
-  153  
-  154  PROCEDURE CopyNm (src: ARRAY OF CHAR; VAR dst: SymTab.Name);
-  155    VAR i: CARDINAL;
-  156    BEGIN
-  157      i := 0;
-  158      WHILE (i <= HIGH(dst)) AND (i <= HIGH(src)) AND (src[i] # CHR(0)) DO
-  159        dst[i] := src[i]; INC(i)
-  160      END;
-  161      IF i <= HIGH(dst) THEN dst[i] := CHR(0) END
-  162    END CopyNm;
-  163  
-  164  PROCEDURE InInst () : BOOLEAN;
-  165    BEGIN RETURN instActive END InInst;
-  166  
-  167  PROCEDURE InstNameGet (VAR nm: SymTab.Name);
-  168    BEGIN CopyNm(instName, nm) END InstNameGet;
-  169  
-  170  PROCEDURE InstActualGet (i: CARDINAL) : SymTab.TypeIndex;
-  171    BEGIN
-  172      IF i >= instN THEN RETURN SymTab.InvalidType END;
-  173      RETURN instActual[i]
-  174    END InstActualGet;
-  175  
-  176  PROCEDURE InstBegin (name: ARRAY OF CHAR);
-  177    BEGIN instActive := TRUE; CopyNm(name, instName); instN := 0;
-  178      instFk := 0 END InstBegin;
-  179  
-  180  PROCEDURE InstAddActual (t: SymTab.TypeIndex);
-  181    BEGIN
-  182      IF instN <= HIGH(instActual) THEN instActual[instN] := t; INC(instN) END
-  183    END InstAddActual;
-  184  
-  185  PROCEDURE InstEnd;
-  186    BEGIN instActive := FALSE; instN := 0 END InstEnd;
+  153    (* Identity of the last-parsed unit and refinement, for the driver's
+  154       generic registry and its re-parse decision. *)
+  155    unitName: SymTab.Name;
+  156    unitWasGen: BOOLEAN;
+  157    unitWasDef: BOOLEAN;
+  158    refSeen: BOOLEAN;
+  159    refIsDef: BOOLEAN;
+  160  
+  161  
+  162  PROCEDURE CopyNm (src: ARRAY OF CHAR; VAR dst: SymTab.Name);
+  163    VAR i: CARDINAL;
+  164    BEGIN
+  165      i := 0;
+  166      WHILE (i <= HIGH(dst)) AND (i <= HIGH(src)) AND (src[i] # CHR(0)) DO
+  167        dst[i] := src[i]; INC(i)
+  168      END;
+  169      IF i <= HIGH(dst) THEN dst[i] := CHR(0) END
+  170    END CopyNm;
+  171  
+  172  PROCEDURE InInst () : BOOLEAN;
+  173    BEGIN RETURN instActive END InInst;
+  174  
+  175  PROCEDURE InstNameGet (VAR nm: SymTab.Name);
+  176    BEGIN CopyNm(instName, nm) END InstNameGet;
+  177  
+  178  PROCEDURE InstActualGet (i: CARDINAL) : SymTab.TypeIndex;
+  179    BEGIN
+  180      IF i >= instN THEN RETURN SymTab.InvalidType END;
+  181      RETURN instActual[i]
+  182    END InstActualGet;
+  183  
+  184  PROCEDURE InstBegin (name: ARRAY OF CHAR);
+  185    BEGIN instActive := TRUE; CopyNm(name, instName); instN := 0;
+  186      instFk := 0 END InstBegin;
   187  
-  188  PROCEDURE UnitNameGet (VAR nm: SymTab.Name);
-  189    BEGIN CopyNm(unitName, nm) END UnitNameGet;
-  190  
-  191  PROCEDURE UnitIsGeneric () : BOOLEAN;
-  192    BEGIN RETURN unitWasGen END UnitIsGeneric;
-  193  
-  194  PROCEDURE UnitIsDefModule () : BOOLEAN;
-  195    BEGIN RETURN unitWasDef END UnitIsDefModule;
-  196  
-  197  PROCEDURE RefineSeen () : BOOLEAN;
-  198    BEGIN RETURN refSeen END RefineSeen;
-  199  
-  200  PROCEDURE RefineIsDef () : BOOLEAN;
-  201    BEGIN RETURN refIsDef END RefineIsDef;
-  202  
-  203  PROCEDURE RefineInst (VAR nm: SymTab.Name);
-  204    BEGIN CopyNm(refInst, nm) END RefineInst;
-  205  
-  206  PROCEDURE RefineGen (VAR nm: SymTab.Name);
-  207    BEGIN CopyNm(refGen, nm) END RefineGen;
-  208  
-  209  PROCEDURE RefineActualCount () : CARDINAL;
-  210    BEGIN RETURN refN END RefineActualCount;
-  211  
-  212  PROCEDURE RefineActualGet (i: CARDINAL) : SymTab.TypeIndex;
-  213    BEGIN
-  214      IF i >= refN THEN RETURN SymTab.InvalidType END;
-  215      RETURN refActual[i]
-  216    END RefineActualGet;
-  217  
-  218  PROCEDURE NoteLabel (nm: ARRAY OF CHAR);
-  219  (* Record a statement label; duplicate is 200. *)
-  220    VAR i: CARDINAL;
+  188  PROCEDURE InstAddActual (t: SymTab.TypeIndex);
+  189    BEGIN
+  190      IF instN <= HIGH(instActual) THEN instActual[instN] := t; INC(instN) END
+  191    END InstAddActual;
+  192  
+  193  PROCEDURE InstEnd;
+  194    BEGIN instActive := FALSE; instN := 0 END InstEnd;
+  195  
+  196  PROCEDURE UnitNameGet (VAR nm: SymTab.Name);
+  197    BEGIN CopyNm(unitName, nm) END UnitNameGet;
+  198  
+  199  PROCEDURE UnitIsGeneric () : BOOLEAN;
+  200    BEGIN RETURN unitWasGen END UnitIsGeneric;
+  201  
+  202  PROCEDURE UnitIsDefModule () : BOOLEAN;
+  203    BEGIN RETURN unitWasDef END UnitIsDefModule;
+  204  
+  205  PROCEDURE RefineSeen () : BOOLEAN;
+  206    BEGIN RETURN refSeen END RefineSeen;
+  207  
+  208  PROCEDURE RefineIsDef () : BOOLEAN;
+  209    BEGIN RETURN refIsDef END RefineIsDef;
+  210  
+  211  PROCEDURE RefineInst (VAR nm: SymTab.Name);
+  212    BEGIN CopyNm(refInst, nm) END RefineInst;
+  213  
+  214  PROCEDURE RefineGen (VAR nm: SymTab.Name);
+  215    BEGIN CopyNm(refGen, nm) END RefineGen;
+  216  
+  217  PROCEDURE RefineActualCount () : CARDINAL;
+  218    BEGIN RETURN refN END RefineActualCount;
+  219  
+  220  PROCEDURE RefineActualGet (i: CARDINAL) : SymTab.TypeIndex;
   221    BEGIN
-  222      i := 0;
-  223      WHILE i < nLab DO
-  224        IF SymTab.Equal(labNm[i], nm) THEN SemError(200); RETURN END;
-  225        INC(i)
-  226      END;
-  227      IF nLab <= HIGH(labNm) THEN
-  228        CopyNm(nm, labNm[nLab]); INC(nLab)
-  229      END
-  230    END NoteLabel;
-  231  
-  232  PROCEDURE NoteGoto (nm: ARRAY OF CHAR);
-  233    VAR i: CARDINAL;
-  234    BEGIN
-  235      i := 0;
-  236      WHILE i < nGot DO
-  237        IF SymTab.Equal(gotNm[i], nm) THEN RETURN END;
-  238        INC(i)
-  239      END;
-  240      IF nGot <= HIGH(gotNm) THEN
-  241        CopyNm(nm, gotNm[nGot]); INC(nGot)
-  242      END
-  243    END NoteGoto;
-  244  
-  245  PROCEDURE CheckGotos;
-  246  (* At a procedure's END: every GOTO must name a label in that procedure. *)
-  247    VAR i, j: CARDINAL; found: BOOLEAN;
-  248    BEGIN
-  249      i := 0;
-  250      WHILE i < nGot DO
-  251        found := FALSE; j := 0;
-  252        WHILE (j < nLab) AND NOT found DO
-  253          IF SymTab.Equal(labNm[j], gotNm[i]) THEN found := TRUE END;
-  254          INC(j)
-  255        END;
-  256        IF NOT found THEN SemError(201) END;
-  257        INC(i)
-  258      END
-  259    END CheckGotos;
-  260  
-  261  PROCEDURE FlushPend;
-  262  (* Emit module-level globals whose forward type is now resolved. *)
-  263    VAR k: CARDINAL;
-  264    BEGIN
-  265      k := 0;
-  266      WHILE k < nPendVar DO
-  267        INC(k)
-  268      END;
-  269      nPendVar := 0
-  270    END FlushPend;
-  271  
-  272  PROCEDURE AstAppend (kind: INTEGER; VAR head, tail: AST.Node;
-  273                       item: AST.Node);
-  274  (* Appends `item` to a chunked sequence: each node holds up to
-  275     AST.MaxChild-1 items; child[MaxChild-1] continues into the next
-  276     chunk.  Unbounded, so blocks/decl sequences are not capped at 8. *)
-  277    VAR n: AST.Node;
-  278    BEGIN
-  279      IF item = AST.NoNode THEN RETURN END;
-  280      IF head = AST.NoNode THEN
-  281        head := AST.MakeNode(kind); tail := head
-  282      END;
-  283      IF AST.NChild(tail) >= AST.MaxChild - 1 THEN
-  284        n := AST.MakeNode(kind);
-  285        AST.SetChild(tail, AST.MaxChild - 1, n);
-  286        tail := n
-  287      END;
-  288      AST.SetChild(tail, AST.NChild(tail), item)
-  289    END AstAppend;
-  290  
-  291  PROCEDURE AstCallNode (callee: AST.Node) : AST.Node;
-  292  (* Builds NkCall(callee, actuals...) from astArgs/astNArgs.  The actuals
-  293     are a chunked sequence (AstAppend): a call can have more than
-  294     MaxChild-1 arguments (the generic ArgList has 9), and SetChild would
-  295     silently drop the tail.  NkBlock marks the continuation chunks. *)
-  296    VAR n, tail: AST.Node; j: CARDINAL;
-  297    BEGIN
-  298      n := AST.MakeNode(AST.NkCall);
-  299      AST.SetChild(n, 0, callee);
-  300      tail := n;
-  301      j := 0;
-  302      WHILE j < astNArgs DO
-  303        AstAppend(AST.NkBlock, n, tail, astArgs[j]);
-  304        INC(j)
-  305      END;
-  306      RETURN n
-  307    END AstCallNode;
-  308  
-  309  
-  310  
-  311  PROCEDURE GetUnit (): AST.Node;
-  312  (* The most recently parsed unit's AST root (for the Lower comparison). *)
-  313    BEGIN
-  314      RETURN astUnit
-  315    END GetUnit;
+  222      IF i >= refN THEN RETURN SymTab.InvalidType END;
+  223      RETURN refActual[i]
+  224    END RefineActualGet;
+  225  
+  226  PROCEDURE NoteLabel (nm: ARRAY OF CHAR);
+  227  (* Record a statement label; duplicate is 200. *)
+  228    VAR i: CARDINAL;
+  229    BEGIN
+  230      i := 0;
+  231      WHILE i < nLab DO
+  232        IF SymTab.Equal(labNm[i], nm) THEN SemError(200); RETURN END;
+  233        INC(i)
+  234      END;
+  235      IF nLab <= HIGH(labNm) THEN
+  236        CopyNm(nm, labNm[nLab]); INC(nLab)
+  237      END
+  238    END NoteLabel;
+  239  
+  240  PROCEDURE NoteGoto (nm: ARRAY OF CHAR);
+  241    VAR i: CARDINAL;
+  242    BEGIN
+  243      i := 0;
+  244      WHILE i < nGot DO
+  245        IF SymTab.Equal(gotNm[i], nm) THEN RETURN END;
+  246        INC(i)
+  247      END;
+  248      IF nGot <= HIGH(gotNm) THEN
+  249        CopyNm(nm, gotNm[nGot]); INC(nGot)
+  250      END
+  251    END NoteGoto;
+  252  
+  253  PROCEDURE CheckGotos;
+  254  (* At a procedure's END: every GOTO must name a label in that procedure. *)
+  255    VAR i, j: CARDINAL; found: BOOLEAN;
+  256    BEGIN
+  257      i := 0;
+  258      WHILE i < nGot DO
+  259        found := FALSE; j := 0;
+  260        WHILE (j < nLab) AND NOT found DO
+  261          IF SymTab.Equal(labNm[j], gotNm[i]) THEN found := TRUE END;
+  262          INC(j)
+  263        END;
+  264        IF NOT found THEN SemError(201) END;
+  265        INC(i)
+  266      END
+  267    END CheckGotos;
+  268  
+  269  PROCEDURE FlushPend;
+  270  (* Emit module-level globals whose forward type is now resolved. *)
+  271    VAR k: CARDINAL;
+  272    BEGIN
+  273      k := 0;
+  274      WHILE k < nPendVar DO
+  275        INC(k)
+  276      END;
+  277      nPendVar := 0
+  278    END FlushPend;
+  279  
+  280  PROCEDURE AstAppend (kind: INTEGER; VAR head, tail: AST.Node;
+  281                       item: AST.Node);
+  282  (* Appends `item` to a chunked sequence: each node holds up to
+  283     AST.MaxChild-1 items; child[MaxChild-1] continues into the next
+  284     chunk.  Unbounded, so blocks/decl sequences are not capped at 8. *)
+  285    VAR n: AST.Node;
+  286    BEGIN
+  287      IF item = AST.NoNode THEN RETURN END;
+  288      IF head = AST.NoNode THEN
+  289        head := AST.MakeNode(kind); tail := head
+  290      END;
+  291      IF AST.NChild(tail) >= AST.MaxChild - 1 THEN
+  292        n := AST.MakeNode(kind);
+  293        AST.SetChild(tail, AST.MaxChild - 1, n);
+  294        tail := n
+  295      END;
+  296      AST.SetChild(tail, AST.NChild(tail), item)
+  297    END AstAppend;
+  298  
+  299  PROCEDURE AstCallNode (callee: AST.Node) : AST.Node;
+  300  (* Builds NkCall(callee, actuals...) from astArgs/astNArgs.  The actuals
+  301     are a chunked sequence (AstAppend): a call can have more than
+  302     MaxChild-1 arguments (the generic ArgList has 9), and SetChild would
+  303     silently drop the tail.  NkBlock marks the continuation chunks. *)
+  304    VAR n, tail: AST.Node; j: CARDINAL;
+  305    BEGIN
+  306      n := AST.MakeNode(AST.NkCall);
+  307      AST.SetChild(n, 0, callee);
+  308      tail := n;
+  309      j := 0;
+  310      WHILE j < astNArgs DO
+  311        AstAppend(AST.NkBlock, n, tail, astArgs[j]);
+  312        INC(j)
+  313      END;
+  314      RETURN n
+  315    END AstCallNode;
   316  
-  317  PROCEDURE SetTwoPhase (b: BOOLEAN);
-  318  (* Driver switch for the two-phase parse probe (milestone 1). *)
-  319    BEGIN
-  320      twoPhaseParse := b
-  321    END SetTwoPhase;
-  322  
-  323  PROCEDURE TokIs (kw: ARRAY OF CHAR): BOOLEAN;
-  324  (* The current lookahead token's source text equals kw.  Compares text,
-  325     not token codes, so grammar renumbering cannot desync the skipper. *)
-  326    VAR tok: ARRAY [0 .. 63] OF CHAR;
+  317  
+  318  
+  319  PROCEDURE GetUnit (): AST.Node;
+  320  (* The most recently parsed unit's AST root (for the Lower comparison). *)
+  321    BEGIN
+  322      RETURN astUnit
+  323    END GetUnit;
+  324  
+  325  PROCEDURE SetTwoPhase (b: BOOLEAN);
+  326  (* Driver switch for the two-phase parse probe (milestone 1). *)
   327    BEGIN
-  328      M2S.GetName(M2S.nextPos, M2S.nextLen, tok);
-  329      RETURN SymTab.Equal(tok, kw)
-  330    END TokIs;
-  331  
-  332  PROCEDURE Adv;
-  333  (* Advance one token: exactly the parser frame's Get for a grammar
-  334     without pragmas (its pragma branch is empty and the scanner never
-  335     returns a token above maxT, so the repeat loop runs once).  A
-  336     separate name because the frame's Get is declared later in this
-  337     module: a bare Get here would bind the imported M2S.Get (which takes
-  338     a parameter) under single-pass compilers. *)
-  339    BEGIN
-  340      M2S.Get(sym);
-  341      INC(errDist)
-  342    END Adv;
-  343  
-  344  PROCEDURE ProbeBody (pn: SymTab.Name);
-  345  (* Shadow-skip the body starting at the current token: consume tokens
-  346     counting block openers until the matching END, check the procedure
-  347     name after it, then restore the exact scanner/parser state.  The
-  348     body then parses normally, so a correct skipper is output-neutral;
-  349     a wrong one reports to StdOut (never into the listing). *)
-  350    VAR savedSym, savedErr, depth, guard: CARDINAL;
-  351      nm: SymTab.Name;
-  352      ok: BOOLEAN;
-  353    BEGIN
-  354      savedSym := sym; savedErr := errDist;
-  355      M2S.PushPos;
-  356      depth := 0; guard := 0; ok := TRUE;
-  357      LOOP
-  358        IF sym = 0 THEN ok := FALSE; EXIT END;
-  359        IF TokIs("END") THEN
-  360          IF depth = 0 THEN EXIT END;
-  361          DEC(depth)
-  362        ELSIF TokIs("MODULE") OR TokIs("PROCEDURE") OR TokIs("CLASS")
-  363           OR TokIs("RECORD") OR TokIs("IF") OR TokIs("CASE")
-  364           OR TokIs("WHILE") OR TokIs("FOR") OR TokIs("LOOP")
-  365           OR TokIs("WITH") THEN
-  366          INC(depth)
-  367        END;
-  368        Adv;
-  369        INC(guard);
-  370        IF guard > 1000000 THEN ok := FALSE; EXIT END
-  371      END;
-  372      IF ok THEN
-  373        Adv;
-  374        M2S.GetName(M2S.nextPos, M2S.nextLen, nm);
-  375        IF (sym = 0) OR NOT SymTab.Equal(nm, pn) THEN ok := FALSE END
-  376      END;
-  377      M2S.PopPos;
-  378      sym := savedSym; errDist := savedErr;
-  379      IF NOT ok THEN
-  380        FileIO.WriteString(FileIO.StdOut, "twophase probe mismatch in ");
-  381        FileIO.WriteString(FileIO.StdOut, pn);
-  382        FileIO.WriteLn(FileIO.StdOut)
-  383      END
-  384    END ProbeBody;
-  385  
-  386  CHARACTERS
-  387    eol      = CHR(13) .
-  388    lf       = CHR(10) .
-  389    letter   = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" .
-  390    digit    = "0123456789" .
-  391    hexDigit = digit + "ABCDEFabcdef" .
-  392    noQuote1 = ANY - "'" - eol .
-  393    noQuote2 = ANY - '"' - eol .
-  394  
-  395  IGNORE CHR(9) .. CHR(13)
-  396  
-  397  COMMENTS FROM "(*" TO "*)" NESTED
-  398  COMMENTS FROM "//" TO lf
-  399  
-  400  TOKENS
-  401    ident   = letter { letter | digit | "_" } .
-  402    integer = digit { digit }
-  403            | digit { digit } CONTEXT("..")
-  404            | "0x" hexDigit { hexDigit }
-  405            | "0X" hexDigit { hexDigit } .
-  406    real    = digit { digit } "." { digit }
-  407              [ ( "E" | "e" ) [ "+" | "-" ] digit { digit } ] .
-  408    string  = "'" { noQuote1 } "'"
-  409            | '"' { noQuote2 } '"' .
-  410    charConst = digit { digit } ( "C" | "c" ) .
-  411    ustring = ( "U" | "u" ) ( "'" { noQuote1 } "'" | '"' { noQuote2 } '"' ) .
-  412  
-  413  PRODUCTIONS
-  414    M2
-  415      = (. twoPhase := TRUE; astCur := AST.NoNode; astStmt := AST.NoNode; astDecl := AST.NoNode; astImp := AST.NoNode; astImpTail := AST.NoNode;
-  416                                             astImp := AST.NoNode;
-  417                                             astImpTail := AST.NoNode;
-  418                                             procNest := 0; .)
-  419        Unit "." .
-  420    (* Units: program modules compile fully; DEFINITION and
-  421       IMPLEMENTATION modules parse + check now but lower in step 4
-  422       (each ends with one 230); same for nested local modules. *)
-  423    (* Generics (Increment 1): formal and actual parameters.  Formals are
-  424       TYPE parameters only; actuals are type identifiers. *)
-  425    GenericFormals
-  426      = "(" GenericFormal { ";" GenericFormal } ")" .
-  427    GenericFormal                         (. VAR nm: SymTab.Name; .)
-  428      = GetIdent<nm>                      (. IF instActive THEN
-  429                                               IF NOT SymTab.EnterTypeParamBound(nm,
-  430                                                  InstActualGet(instFk)) THEN
-  431                                                 SemError(200) END
-  432                                             ELSIF NOT SymTab.EnterTypeParam(nm) THEN
-  433                                               SemError(200) END;
-  434                                             INC(instFk); .)
-  435        { "," GetIdent<nm>                (. IF instActive THEN
-  436                                               IF NOT SymTab.EnterTypeParamBound(nm,
-  437                                                  InstActualGet(instFk)) THEN
-  438                                                 SemError(200) END
-  439                                             ELSIF NOT SymTab.EnterTypeParam(nm) THEN
-  440                                               SemError(200) END;
-  441                                             INC(instFk); .) }
-  442        ":" "TYPE" .
-  443    Actuals
-  444      = Actual { "," Actual } .
-  445    Actual                                (. VAR at: SymTab.TypeIndex; .)
-  446      = TypeIdent<at>                     (. IF refN <= HIGH(refActual) THEN
-  447                                               refActual[refN] := at; INC(refN)
-  448                                             END; .) .
-  449    Unit
-  450      =                                   (. isGen := FALSE; .)
-  451        [ "GENERIC"                       (. isGen := TRUE; .) ]
-  452        ( DefUnit | ImplUnit | ProgModule ) .
-  453    (* Step 4.3: one session compiles DEFINITION, its IMPLEMENTATION
-  454       and one program (last) into one image. Units share the symbol
-  455       table; imports materialize exported names. *)
-  456    DefUnit                               (. VAR m1, m2, pn: SymTab.Name;
-  457                                               g: SymTab.Name;
-  458                                               astSeq, astTail, astProc: AST.Node; .)
-  459      =                                   (. refN := 0; refSeen := FALSE; .)
-  460        "DEFINITION" "MODULE"
-  461        GetIdent<m1>                      (. IF instActive THEN InstNameGet(m1) END;
-  462                                             IF instActive THEN
-  463                                               IF NOT SymTab.Reenter(m1,
-  464                                                      SymTab.UnitDef) THEN
-  465                                                 SemError(200) END
-  466                                             ELSIF NOT SymTab.BeginDef(m1) THEN
-  467                                               SemError(200) END;
-  468                                             QbeGen.SetModule(m1);
-  469                                             CopyNm(m1, unitName);
-  470                                             unitWasGen := isGen
-  471                                               AND NOT instActive;
-  472                                             unitWasDef := TRUE; .)
-  473        [ GenericFormals ]
-  474        ( ";"
-  475        { Import                        (. AstAppend(AST.NkDeclSeq,
-  476                                               astImp, astImpTail, astDecl); .) }
-  477        [ "EXPORT" [ "QUALIFIED" ]        (. (* definition-module export
-  478                                                list: parsed, and the
-  479                                                names are already exported
-  480                                                by the module scope *) .)
-  481          GetIdent<pn> { "," GetIdent<pn> } ";" ]
-  482                                          (. astSeq := AST.NoNode;
-  483                                             astTail := AST.NoNode; .)
-  484        { ConstBlock                      (. AstAppend(AST.NkDeclSeq,
-  485                                               astSeq, astTail, astDecl); .)
-  486        | TypeBlock<TRUE>                 (. AstAppend(AST.NkDeclSeq,
-  487                                               astSeq, astTail, astDecl); .)
-  488        | VarBlock                        (. AstAppend(AST.NkDeclSeq,
-  489                                               astSeq, astTail, astDecl); .)
-  490        | ProcHeading<pn, SymTab.InvalidType> ";"
-  491                                          (. (* a heading only: record it so
-  492                                                Lower can replay it *)
-  493                                             astProc := AST.MakeNode(AST.NkProcDecl);
-  494                                             AST.SetOp(astProc, 0);
-  495                                             AST.SetChild(astProc, 0,
-  496                                               AST.MakeLeaf(AST.NkIdent, pn));
-  497                                             AstAppend(AST.NkDeclSeq,
-  498                                               astSeq, astTail, astProc);
-  499                                             Lower.NoteProcNode(astProc);
-  500                                             Lower.ScopeLeave;
-  501                                             SymTab.CloseProc;
-  502                                             QbeGen.AbortFunc; .) }
-  503                                          (. astUnit := AST.MakeNode(AST.NkUnit);
-  504                                             AST.SetChild(astUnit, 0,
-  505                                               AST.MakeLeaf(AST.NkIdent, m1));
-  506                                             AST.SetChild(astUnit, 1, astSeq);
-  507                                             AST.SetChild(astUnit, 3, astImp);
-  508                                             astDecl := AST.NoNode;
-  509                                             astStmt := AST.NoNode; .)
-  510        "END"
-  511        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
-  512                                             IF NOT SymTab.Equal(m1, m2) THEN
-  513                                               SemError(202) END;
-  514                                             SymTab.EndUnit; .)
-  515        | "=" GetIdent<g> [ "(" Actuals ")" ] ";"
-  516                                          (. CopyNm(m1, refInst);
-  517                                             CopyNm(g, refGen);
-  518                                             refSeen := TRUE; refIsDef := TRUE;
-  519                                             astUnit := AST.MakeNode(AST.NkUnit);
-  520                                             AST.SetChild(astUnit, 0,
-  521                                               AST.MakeLeaf(AST.NkIdent, m1));
-  522                                             astDecl := AST.NoNode;
-  523                                             astStmt := AST.NoNode; .)
-  524          "END"
-  525          GetIdent<m2>                    (. IF NOT SymTab.Equal(m1, m2) THEN
-  526                                               SemError(202) END;
-  527                                             SymTab.EndUnit; .) ) .
-  528    ImplUnit                              (. VAR m1, m2: SymTab.Name;
-  529                                               g: SymTab.Name;
-  530                                               k: CARDINAL;
-  531                                               fname: SymTab.Name;
-  532                                               unres: BOOLEAN;
-  533                                               astNode: AST.Node; .)
-  534      =                                   (. refN := 0; refSeen := FALSE; .)
-  535        "IMPLEMENTATION" "MODULE"
-  536        GetIdent<m1> (. IF instActive THEN InstNameGet(m1) END;
-  537                       IF instActive THEN
-  538                         IF NOT SymTab.Reenter(m1,
-  539                                SymTab.UnitImpl) THEN
-  540                           SemError(201) END
-  541                       ELSIF NOT SymTab.BeginImpl(m1) THEN
-  542                         SemError(201) END;
-  543                       astStmt := AST.NoNode;
-  544                       astDecl := AST.NoNode;
-  545                       astImp := AST.NoNode;
-  546                       astImpTail := AST.NoNode;
-  547                       nPendVar := 0;
-  548                       CopyNm(m1, unitName);
-  549                       unitWasGen := isGen AND NOT instActive;
-  550                       unitWasDef := FALSE;
-  551                       QbeGen.SetModule(m1); .)
-  552        [ GenericFormals ]
-  553        ( ";"
-  554        { Import                        (. AstAppend(AST.NkDeclSeq,
-  555                                               astImp, astImpTail, astDecl); .) }
-  556        DeclSeq                           (. astStmt := AST.NoNode; .)
-  557        [ "BEGIN"                         (. FlushPend;
-  558                                             k := 0;
-  559                                             WHILE k < SymTab.FwdPending() DO
-  560                                               SymTab.FwdInfo(k, fname, unres);
-  561                                               IF unres THEN SemError(201) END;
-  562                                               INC(k)
-  563                                             END;
-  564                                             SymTab.FwdClear;
-  565  
-  566                                             nLab := 0; nGot := 0; .)
-  567          [ StatSeq ] ]
-  568        "END"
-  569        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
-  570                                             FlushPend;
-  571                                             k := 0;
-  572                                             WHILE k < SymTab.FwdPending() DO
-  573                                               SymTab.FwdInfo(k, fname, unres);
-  574                                               IF unres THEN SemError(201) END;
-  575                                               INC(k)
-  576                                             END;
-  577                                             SymTab.FwdClear;
-  578  
-  579                                             astNode := AST.MakeNode(AST.NkUnit);
-  580                                             AST.SetChild(astNode, 0,
-  581                                               AST.MakeLeaf(AST.NkIdent, m1));
-  582                                             AST.SetChild(astNode, 1, astDecl);
-  583                                             AST.SetChild(astNode, 2, astStmt);
-  584                                             AST.SetChild(astNode, 3, astImp);
-  585                                             astUnit := astNode;
-  586                                             IF NOT SymTab.Equal(m1, m2) THEN
-  587                                               SemError(202) END;
-  588                                             CheckGotos;
-  589                                             SymTab.EndUnit; .)
-  590        | "=" GetIdent<g> [ "(" Actuals ")" ] ";"
-  591                                          (. CopyNm(m1, refInst);
-  592                                             CopyNm(g, refGen);
-  593                                             refSeen := TRUE; refIsDef := FALSE;
-  594                                             astNode := AST.MakeNode(AST.NkUnit);
-  595                                             AST.SetChild(astNode, 0,
-  596                                               AST.MakeLeaf(AST.NkIdent, m1));
-  597                                             astDecl := AST.NoNode;
-  598                                             astStmt := AST.NoNode; .)
-  599          "END"
-  600          GetIdent<m2>                    (. IF NOT SymTab.Equal(m1, m2) THEN
-  601                                               SemError(202) END;
-  602                                             SymTab.EndUnit; .) ) .
-  603    ProgModule                            (. VAR m1, m2: SymTab.Name;
-  604                                               k: CARDINAL;
-  605                                               fname: SymTab.Name;
-  606                                               unres: BOOLEAN;
-  607                                               astNode: AST.Node; .)
-  608      = "MODULE"
-  609        GetIdent<m1> (. IF NOT SymTab.BeginProg(m1) THEN
-  610                                               SemError(200) END;
-  611                                             astStmt := AST.NoNode;
-  612                                             astDecl := AST.NoNode;
-  613                                             astImp := AST.NoNode;
-  614                                             astImpTail := AST.NoNode;
-  615                                             nPendVar := 0;
-  616                                             QbeGen.SetModule(m1); .)
-  617        [ Priority ]
-  618        ";"
-  619        { Import                        (. AstAppend(AST.NkDeclSeq,
-  620                                               astImp, astImpTail, astDecl); .) }
-  621        DeclSeq                           (. astStmt := AST.NoNode; .)
-  622        [ "BEGIN"                         (. FlushPend;
-  623                                             k := 0;
-  624                                             WHILE k < SymTab.FwdPending() DO
-  625                                               SymTab.FwdInfo(k, fname, unres);
-  626                                               IF unres THEN SemError(201) END;
-  627                                               INC(k)
-  628                                             END;
-  629                                             SymTab.FwdClear;
-  630  
-  631                                             nLab := 0; nGot := 0; .)
-  632          [ StatSeq ] ]
-  633        "END"
-  634        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
-  635                                             FlushPend;
-  636                                             k := 0;
-  637                                             WHILE k < SymTab.FwdPending() DO
-  638                                               SymTab.FwdInfo(k, fname, unres);
-  639                                               IF unres THEN SemError(201) END;
-  640                                               INC(k)
-  641                                             END;
-  642                                             SymTab.FwdClear;
-  643  
-  644                                             IF NOT SymTab.Equal(m1, m2) THEN
-  645                                               SemError(202) END;
-  646                                             astNode := AST.MakeNode(AST.NkUnit);
-  647                                             AST.SetChild(astNode, 0,
-  648                                               AST.MakeLeaf(AST.NkIdent, m1));
-  649                                             AST.SetChild(astNode, 1, astDecl);
-  650                                             AST.SetChild(astNode, 2, astStmt);
-  651                                             AST.SetChild(astNode, 3, astImp);
-  652                                             astUnit := astNode;
-  653                                             CheckGotos;
-  654                                             SymTab.EndUnit; .) .
-  655    DeclSeq                               (. VAR astSeq, astTail: AST.Node; .)
-  656      =                                   (. astSeq := AST.NoNode;
-  657                                             astTail := AST.NoNode; .)
-  658        { (. astDecl := AST.NoNode; .)
-  659          ( ConstBlock | TypeBlock<FALSE> | VarBlock | ProcDecl ";"
-  660          | NestedModule ";" | ClassItem ";" )
-  661                                          (. AstAppend(AST.NkDeclSeq,
-  662                                               astSeq, astTail, astDecl); .) }
-  663                                          (. astDecl := astSeq; .) .
-  664    (* Local module, Wirth form. Declarations lower like top-level ones
-  665       (same QBE module prefix); a BEGIN body becomes an init function
-  666       that main calls; the EXPORT list is hoisted into the enclosing
-  667       scope at END. *)
-  668    NestedModule                          (. VAR m1, m2: SymTab.Name;
-  669                                               expNames: ARRAY [0 .. 63] OF SymTab.Name;
-  670                                               expCount, k: CARDINAL;
-  671                                               astNode, nImp, nImpTail:
-  672                                                 AST.Node; .)
-  673      = "MODULE"
-  674        GetIdent<m1>                      (. IF NOT SymTab.Enter(m1,
-  675                                               SymTab.KindModule) THEN
-  676                                               SemError(200) END;
-  677                                             SymTab.PushScope;
-  678                                             expCount := 0;
-  679                                             astNode := AST.MakeNode(AST.NkUnit);
-  680                                             AST.SetChild(astNode, 0,
-  681                                               AST.MakeLeaf(AST.NkIdent, m1));
-  682                                             astStmt := AST.NoNode;
-  683                                             astDecl := AST.NoNode;
-  684                                             nImp := AST.NoNode;
-  685                                             nImpTail := AST.NoNode; .)
-  686        [ Priority ]
-  687        ";"
-  688        { Import                        (. AstAppend(AST.NkDeclSeq,
-  689                                               nImp, nImpTail, astDecl); .) }
-  690        [ "EXPORT" [ "QUALIFIED" ]
-  691          GetIdent<expNames[expCount]>    (. INC(expCount); .)
-  692          { "," GetIdent<expNames[expCount]>
-  693                                          (. INC(expCount); .) }
-  694          ";" ]
-  695        DeclSeq                           (. astStmt := AST.NoNode; .)
-  696        [ "BEGIN"                         (. astStmt := AST.NoNode;
-  697                                             .)
-  698          [ StatSeq ] ]
-  699        "END"
-  700        GetIdent<m2>                      (. AST.SetChild(astNode, 1, astDecl);
-  701                                             AST.SetChild(astNode, 2, astStmt);
-  702                                             AST.SetChild(astNode, 3, nImp);
-  703                                             astDecl := astNode;
-  704                                             IF NOT SymTab.Equal(m1, m2) THEN
-  705                                               SemError(202) END;
-  706                                             k := 0;
-  707                                             WHILE k < expCount DO
-  708                                               SymTab.ExportUp(expNames[k]);
-  709                                               INC(k)
-  710                                             END;
-  711                                             SymTab.PopScope; .) .
-  712    Priority
-  713      = "[" integer "]"                   (. SemError(230); .) .
-  714    (* Imports (4.3): FROM materializes the names (unqualified use);
-  715       plain IMPORT only demands the module exists — qualified `L.x`
-  716       materializes on first use (Design). *)
-  717    (* Unknown modules stay unchecked stubs (legacy, so hand-written
-  718       import lines don't fail); a known module's missing export is
-  719       201. *)
-  720    Import                                (. VAR n: SymTab.Name;
-  721                                               astImport: AST.Node; .)
-  722      = "FROM"
-  723        GetIdent<n>                       (. astImport := AST.MakeNode(AST.NkImport);
-  724                                             AST.SetChild(astImport, 0,
-  725                                               AST.MakeLeaf(AST.NkIdent, n)); .)
-  726        "IMPORT"
-  727        ImpList<n, astImport> ";"         (. astDecl := astImport; .)
-  728      | "IMPORT"                          (. astImport := AST.MakeNode(AST.NkImport); .)
-  729        ImpModList<astImport> ";"         (. astDecl := astImport; .) .
-  730    ImpList<mod: SymTab.Name; node: AST.Node>
-  731                                          (. VAR n: SymTab.Name; .)
-  732      = ImpName<mod, node>
-  733        { "," ImpName<mod, node> } .
-  734    (* Pervasive built-ins imported from SYSTEM (e.g. TSIZE) are
-  735       accepted and ignored: the built-in applies regardless. *)
-  736    ImpName<mod: SymTab.Name; node: AST.Node>
-  737                                          (. VAR n: SymTab.Name; .)
-  738      = GetIdent<n> (. AST.SetChild(node, AST.NChild(node),
-  739                                               AST.MakeLeaf(AST.NkIdent, n));
-  740                                             IF SymTab.Equal(mod, "libc") THEN
-  741                                               (* intrinsic C library:
-  742                                                  permissive external *)
-  743                                               IF NOT SymTab.DeclareCProc(n) THEN
-  744                                                 SemError(201) END;
-  745                                               Lower.NoteCProc(n)
-  746                                             ELSIF SymTab.ModKnown(mod) THEN
-  747                                               IF NOT SymTab.ImportFrom(mod, n) THEN
-  748                                                 SemError(201)
-  749                                               ELSE Lower.NoteImportedProc(n)
-  750                                               END
-  751                                             END; .)
-  752      | ( "TSIZE" | "SIZE" | "ADR" | "HIGH" | "LEN"
-  753        | "CHR" | "ORD" | "ORDL" | "VAL" | "ABS" | "CAP"
-  754        | "UCHR" | "CHR8" | "UORD"
-  755        | "INC" | "DEC" ) .
-  756    ImpModList<node: AST.Node>            (. VAR n: SymTab.Name; .)
-  757      = GetIdent<n>                       (. AST.SetChild(node, AST.NChild(node),
-  758                                               AST.MakeLeaf(AST.NkIdent, n)); .)
-  759        { "," GetIdent<n>                 (. AST.SetChild(node, AST.NChild(node),
-  760                                               AST.MakeLeaf(AST.NkIdent, n)); .) } .
-  761    (* Opaque TYPE declarations (definition modules). The targetless
-  762       alias resolves to InvalidType until step 4 completes it. *)
-  763    (* Scalar-phase TYPEs: named types, integer subranges, enumerations.
-  764       Opaque "TYPE T;" needs isDef (definition units); elsewhere 231.
-  765       Composite forms (ARRAY/RECORD/SET/POINTER) arrive with step 3. *)
-  766    TypeBlock<isDef: BOOLEAN>             (. VAR astSeq, astTail: AST.Node; .)
-  767      = "TYPE"                            (. SymTab.BeginTypeBlock;
-  768                                             astSeq := AST.NoNode;
-  769                                             astTail := AST.NoNode; .)
-  770        { (. astDecl := AST.NoNode; .)
-  771          ( TypeItem<isDef> ";" | ClassItem ";" )
-  772                                          (. AstAppend(AST.NkDeclSeq,
-  773                                               astSeq, astTail, astDecl); .) }
-  774                                          (. SymTab.EndTypeBlock;
-  775                                             astDecl := astSeq; .) .
-  776    TypeItem<isDef: BOOLEAN>              (. VAR n: SymTab.Name;
-  777                                               t, op: SymTab.TypeIndex;
-  778                                               astNode: AST.Node; .)
-  779      = GetIdent<n>                       (. op := SymTab.OpaqueBase(n);
-  780                                             IF op = SymTab.InvalidType THEN
-  781                                               IF NOT SymTab.Enter(n,
-  782                                                  SymTab.KindType) THEN
-  783                                                 SemError(200) END
-  784                                             END; .)
-  785        ( "=" Type<t, FALSE> (. astNode := AST.MakeNode(AST.NkTypeDecl);
-  786                                               AST.SetChild(astNode, 0,
-  787                                                 AST.MakeLeaf(AST.NkIdent, n));
-  788                                               AST.SetTy(astNode, t);
-  789                                               astDecl := astNode;
-  790                                               IF op # SymTab.InvalidType THEN
-  791                                               SymTab.SetTarget(op, t)
-  792                                             ELSE SymTab.SetSymType(n, t)
-  793                                             END; .)
-  794        |                                 (. IF op # SymTab.InvalidType THEN
-  795                                               (* stays opaque *)
-  796                                             ELSIF NOT isDef THEN
-  797                                               SemError(231)
-  798                                             ELSE SymTab.SetSymType(n,
-  799                                               SymTab.NewAlias()) END; .) ) .
-  800    Type<VAR t: SymTab.TypeIndex; allowOpen: BOOLEAN>
-  801      = TypeIdent<t> [ Subrange<t> ]     (* anchored subrange: T[lo..hi] *)
-  802      | Subrange<t>
-  803      | Enum<t>
-  804      | ArrayType<t, allowOpen>
-  805      | SetType<t>
-  806      | RecordType<t>
-  807      | PointerType<t>
-  808      | ProcType<t> .
-  809    PointerType<VAR t: SymTab.TypeIndex>  (. VAR base: SymTab.TypeIndex; .)
-  810      = "POINTER" "TO" Type<base, FALSE>(. t := SymTab.NewPtr(base); .) .
-  811    (* Procedure types (step 8.5): PROCEDURE (params): result. Values
-  812       are code pointers; params are collected into the descriptor. *)
-  813    ProcType<VAR t: SymTab.TypeIndex>     (. VAR res, pt: SymTab.TypeIndex;
-  814                                               isV: BOOLEAN; .)
-  815      = "PROCEDURE"                       (. res := SymTab.InvalidType;
-  816                                             t := SymTab.NewProcType(res); .)
-  817        [ "(" [ ProcTypeSection<t> { ";" ProcTypeSection<t> } ] ")" ]
-  818        [ ":" TypeIdent<res>              (. SymTab.SetProcTypeRes(t, res); .) ] .
-  819    ProcTypeSection<t: SymTab.TypeIndex>  (. VAR pt: SymTab.TypeIndex;
-  820                                               isV: BOOLEAN;
-  821                                               cnt, k: CARDINAL;
-  822                                               names: ARRAY [0 .. 15] OF SymTab.Name; .)
-  823      =                                   (. isV := FALSE; cnt := 0; .)
-  824        [ "VAR"                           (. isV := TRUE; .) ]
-  825        ( GetIdent<names[cnt]>            (. INC(cnt); .)
-  826          { "," GetIdent<names[cnt]>      (. INC(cnt); .) }
-  827          ( ":" Type<pt, TRUE>           (. k := 0;
-  828                                             WHILE k < cnt DO
-  829                                               SymTab.ProcTypeAdd(t, isV, pt);
-  830                                               INC(k)
-  831                                             END; .)
-  832          |                               (. (* type-only parameter list:
-  833                                                each name is a type (GNU
-  834                                                shorthand used by the
-  835                                                Coco/R scanner frame) *)
-  836                                             k := 0;
-  837                                             WHILE k < cnt DO
-  838                                               IF SymTab.Lookup(names[k])
-  839                                                  AND ((SymTab.SymKind(names[k]) = SymTab.KindType)
-  840    OR (SymTab.SymKind(names[k]) = SymTab.KindPredef)) THEN
-  841                                                 pt := SymTab.SymType(names[k])
-  842                                               ELSE SemError(201);
-  843                                                 pt := SymTab.InvalidType
-  844                                               END;
-  845                                               SymTab.ProcTypeAdd(t, isV, pt);
-  846                                               INC(k)
-  847                                             END; .) )
-  848        | Type<pt, TRUE>                 (. (* unnamed parameter (PIM):
-  849                                                e.g. PROCEDURE (VAR ARRAY OF REAL) *)
-  850                                             SymTab.ProcTypeAdd(t, isV, pt); .) ) .
-  851    (* Arrays: "OF" without bounds is an open formal (allowed only
-  852       where allowOpen); "[lo..hi, ...]" nests bounded levels inside
-  853       out. Bounds are folded literals (int/char); anything else 230.
-  854       Bare-type indices ("ARRAY Color OF") wait for enum ordinals. *)
-  855    ArrayType<VAR t: SymTab.TypeIndex; allowOpen: BOOLEAN>
-  856                                          (. VAR elem: SymTab.TypeIndex;
-  857                                               ok: BOOLEAN;
-  858                                               bnds, bndh: ARRAY [0 .. 7] OF INTEGER;
-  859                                               nb, k: CARDINAL;
-  860                                               idx: SymTab.TypeIndex;
-  861                                               ilo, ihi: INTEGER; .)
-  862      = "ARRAY"
-  863        ( "OF" Type<elem, FALSE>          (. IF NOT allowOpen THEN
-  864                                               SemError(230) END;
-  865                                             t := SymTab.NewOpenArray(elem); .)
-  866        | TypeIdent<idx> [ Subrange<idx> ]
-  867          "OF" Type<elem, FALSE>          (. (* index-type array: the index
-  868                                                type's ordinal bounds give the
-  869                                                [lo..hi] pair *)
-  870                                             IF SymTab.TypeBounds(idx, ilo,
-  871                                                ihi)
-  872                                             THEN t := SymTab.NewArrayB(elem,
-  873                                                    ilo, ihi)
-  874                                             ELSE SemError(230);
-  875                                               t := SymTab.InvalidType
-  876                                             END; .)
-  877        | "["                             (. SymTab.BoundBegin; ok := TRUE; .)
-  878          BoundPair<ok>
-  879          { "," BoundPair<ok> }
-  880          "]"                             (. (* snapshot before the element
-  881                                                type, which reuses the bound
-  882                                                buffer for a nested ARRAY *)
-  883                                             nb := SymTab.BoundCount();
-  884                                             k := 0;
-  885                                             WHILE k < nb DO
-  886                                               bnds[k] := SymTab.BoundLo(k);
-  887                                               bndh[k] := SymTab.BoundHi(k);
-  888                                               INC(k)
-  889                                             END; .)
-  890          "OF" Type<elem, FALSE>
-  891                                          (. IF ok THEN
-  892                                               k := nb;
-  893                                               WHILE k > 0 DO
-  894                                                 DEC(k);
-  895                                                 elem := SymTab.NewArrayB(
-  896                                                   elem, bnds[k], bndh[k])
-  897                                               END;
-  898                                               t := elem
-  899                                             ELSE t := SymTab.InvalidType
-  900                                             END; .) ) .
-  901    BoundPair<VAR ok: BOOLEAN>            (. VAR tlo, thi: SymTab.TypeIndex;
-  902                                               qlo, qhi: QbeGen.QVal;
-  903                                               lo, hi: INTEGER;
-  904                                               cl, cl2: INTEGER; .)
-  905      = Expr<tlo, qlo> ".." Expr<thi, qhi>
-  906                                          (. IF (tlo = SymTab.InvalidType)
-  907                                              OR (thi = SymTab.InvalidType) THEN
-  908                                             ok := FALSE
-  909                                           ELSE cl := SymTab.ClassOf(tlo);
-  910                                             cl2 := SymTab.ClassOf(thi);
-  911                                             IF ((cl # SymTab.ClInt)
-  912   AND (cl # SymTab.ClChar))
-  913                                                OR ((cl2 # SymTab.ClInt)
-  914   AND (cl2 # SymTab.ClChar)) THEN
-  915                                               SemError(230); ok := FALSE
-  916                                             ELSIF NOT SymTab.ConstInt(qlo, lo)
-  917                                                OR NOT SymTab.ConstInt(qhi, hi)
-  918                                                OR (lo > hi) THEN
-  919                                               SemError(230); ok := FALSE
-  920                                              ELSIF NOT SymTab.BoundAdd(lo, hi) THEN
-  921                                                SemError(230); ok := FALSE
-  922                                              END;
-  923                                            END; .) .
-  924    (* Sets: multi-word masks over bases ≤ 256 values (bool, char,
-  925       bounded subranges; enums wait for ordinals, INTEGER is
-  926       unbounded). Literals are SET OF [0..255]; assignment and
-  927       comparison across suitable bases are lenient (masks over min
-  928       words + zero-check extras), out-of-span literals are 222. *)
-  929    SetType<VAR t: SymTab.TypeIndex>      (. VAR base: SymTab.TypeIndex;
-  930                                               blo, bhi, bspan: INTEGER;
-  931                                               bcls: INTEGER; .)
-  932      = "SET" "OF" Type<base, FALSE>
-  933                                          (. IF base = SymTab.InvalidType THEN
-  934                                               t := SymTab.InvalidType
-  935                                             ELSE bcls :=
-  936                                                    SymTab.ClassOf(base);
-  937                                               IF bcls = SymTab.ClBool THEN
-  938                                                 blo := 0; bspan := 2
-  939                                               ELSIF bcls = SymTab.ClChar THEN
-  940                                                 blo := 0; bspan := 256
-  941                                               ELSIF bcls = SymTab.ClEnum THEN
-  942                                                 blo := 0;
-  943                                                 bspan := VAL(INTEGER,
-  944                                                   SymTab.EnumCount(base))
-  945                                               ELSIF SymTab.SubBounds(base,
-  946                                                       blo, bhi) THEN
-  947                                                 bspan := bhi - blo + 1
-  948                                               ELSE bspan := 0 END;
-  949                                               IF (bspan <= 0)
-  950                                                  OR (bspan > 65536) THEN
-  951                                                 SemError(230);
-  952                                                 t := SymTab.InvalidType
-  953                                               ELSE t := SymTab.NewSet(base)
-  954                                               END
-  955                                             END; .) .
-  956    (* Records: flat blobs; array fields are pointers to static
-  957       descriptors (locked amendment), nested records inline. Field
-  958       offsets static and declaration-ordered. *)
-  959    (* Field list: plain fields and (optionally) one variant part.  The
-  960       variant part is a `CASE ... END` item; because it starts with the
-  961       CASE keyword it is unambiguously distinguishable from a field
-  962       (which starts with an identifier). *)
-  963    RecordType<VAR t: SymTab.TypeIndex>   (. VAR t2: SymTab.TypeIndex;
-  964                                               tagOk: BOOLEAN; .)
-  965      = "RECORD"                          (. t := SymTab.NewRecord(); .)
-  966        [ RecItem<t> { ";" [ RecItem<t> ] } ]
-  967        "END"                             (. SymTab.LayoutRecord(t); .) .
-  968    RecItem<rec: SymTab.TypeIndex>        (. VAR tt: SymTab.TypeIndex; .)
-  969      = RecField<rec>
-  970      | CaseField<rec>                    (. SymTab.MarkVariant(rec); .) .
-  971    (* A variant part: CASE tag : Type OF variants.  The layout overlays
-  972       every branch from the tag slot (see SymTab.ComputeOffsets). *)
-  973    CaseField<rec: SymTab.TypeIndex>      (. VAR tagT: SymTab.TypeIndex;
-  974                                               tagN: SymTab.Name; .)
-  975      = "CASE"                            (. SymTab.ResetFields(rec); .)
-  976        GetIdent<tagN>                    (. IF NOT SymTab.FieldPending(rec,
-  977                                               tagN) THEN
-  978                                               SemError(200) END; .)
-  979        ":" Type<tagT, FALSE>             (. IF (tagT # SymTab.InvalidType)
-  980    AND NOT SymTab.IsOrdinal(tagT) THEN
-  981                                               SemError(224)
-  982                                             END;
-  983                                             SymTab.FixPendingF(rec, tagT);
-  984                                             SymTab.SetVariantTag(rec, tagN); .)
-  985        "OF"
-  986        RecFieldList<rec>
-  987        { "|"                             (. SymTab.ResetFields(rec); .)
-  988          RecFieldList<rec> }
-  989        "END" .
-  990    RecFieldList<rec: SymTab.TypeIndex>   (. VAR lt, lq: SymTab.TypeIndex;
-  991                                               lv1, lv2: QbeGen.QVal; .)
-  992      = VarLabel<lt, lv1> [ ".." VarLabel<lq, lv2> ] ":"
-  993        RecField<rec> { ";" [ RecField<rec> ] } .
-  994    (* Variant case label: a constant (or a constant range).  Values are
-  995       not interpreted (the layout overlays regardless). *)
-  996    VarLabel<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
-  997                                          (. VAR lname: SymTab.Name; .)
-  998      = ( ident                         (. LexName(lname);
-  999                                             QbeGen.CopyOp("0", q);
- 1000                                             t := SymTab.IntType(); .)
- 1001        | integer                       (. LexString(lname);
- 1002                                             QbeGen.CopyOp("0", q);
- 1003                                             t := SymTab.IntType(); .)
- 1004        | charConst                     (. LexString(lname);
- 1005                                             QbeGen.CopyOp("0", q);
- 1006                                             t := SymTab.CharType(); .) ) .
- 1007    RecField<rec: SymTab.TypeIndex>       (. VAR n: SymTab.Name;
- 1008                                               t2: SymTab.TypeIndex; .)
- 1009      = RecIdents<rec> ":" Type<t2, FALSE>(. SymTab.FixPendingF(rec, t2); .) .
- 1010    RecIdents<rec: SymTab.TypeIndex>      (. VAR n: SymTab.Name; .)
- 1011      = GetIdent<n>                       (. IF NOT SymTab.FieldPending(rec,
- 1012                                               n) THEN
+  328      twoPhaseParse := b
+  329    END SetTwoPhase;
+  330  
+  331  PROCEDURE TokIs (kw: ARRAY OF CHAR): BOOLEAN;
+  332  (* The current lookahead token's source text equals kw.  Compares text,
+  333     not token codes, so grammar renumbering cannot desync the skipper. *)
+  334    VAR tok: ARRAY [0 .. 63] OF CHAR;
+  335    BEGIN
+  336      M2S.GetName(M2S.nextPos, M2S.nextLen, tok);
+  337      RETURN SymTab.Equal(tok, kw)
+  338    END TokIs;
+  339  
+  340  PROCEDURE Adv;
+  341  (* Advance one token: exactly the parser frame's Get for a grammar
+  342     without pragmas (its pragma branch is empty and the scanner never
+  343     returns a token above maxT, so the repeat loop runs once).  A
+  344     separate name because the frame's Get is declared later in this
+  345     module: a bare Get here would bind the imported M2S.Get (which takes
+  346     a parameter) under single-pass compilers. *)
+  347    BEGIN
+  348      M2S.Get(sym);
+  349      INC(errDist)
+  350    END Adv;
+  351  
+  352  PROCEDURE NoteSpan (pn: SymTab.Name; start: M2S.INT32);
+  353  (* Records an outermost body span for the re-parse pass (milestone 2).
+  354     Diagnostic only for now: nothing consumes the table yet.  Declared
+  355     before its caller: V3 resolves single-pass (declaration before use),
+  356     with no forward tolerance for procedure calls. *)
+  357    BEGIN
+  358      IF nSpans > HIGH(spanName) THEN RETURN END;
+  359      CopyNm(pn, spanName[nSpans]);
+  360      spanStart[nSpans] := start;
+  361      INC(nSpans)
+  362    END NoteSpan;
+  363  
+  364  PROCEDURE ProbeBody (pn: SymTab.Name);
+  365  (* Shadow-skip the body starting at the current token: consume tokens
+  366     counting block openers until the matching END, check the procedure
+  367     name after it, record the body span for the re-parse pass, verify
+  368     SeekTo repositions exactly, then restore the exact scanner/parser
+  369     state.  The body then parses normally, so a correct skipper is
+  370     output-neutral; a wrong one reports to StdOut (never into the
+  371     listing).  The SeekTo check's side effects are discarded by the
+  372     trailing PopPos, so it is output-neutral too. *)
+  373    VAR savedSym, savedErr, depth, guard: CARDINAL;
+  374      nm: SymTab.Name;
+  375      ok, sok: BOOLEAN;
+  376      start: M2S.INT32;
+  377    BEGIN
+  378      savedSym := sym; savedErr := errDist; start := M2S.nextPos;
+  379      M2S.PushPos;
+  380      depth := 0; guard := 0; ok := TRUE;
+  381      LOOP
+  382        IF sym = 0 THEN ok := FALSE; EXIT END;
+  383        IF TokIs("END") THEN
+  384          IF depth = 0 THEN EXIT END;
+  385          DEC(depth)
+  386        ELSIF TokIs("MODULE") OR TokIs("PROCEDURE") OR TokIs("CLASS")
+  387           OR TokIs("RECORD") OR TokIs("IF") OR TokIs("CASE")
+  388           OR TokIs("WHILE") OR TokIs("FOR") OR TokIs("LOOP")
+  389           OR TokIs("WITH") THEN
+  390          INC(depth)
+  391        END;
+  392        Adv;
+  393        INC(guard);
+  394        IF guard > 1000000 THEN ok := FALSE; EXIT END
+  395      END;
+  396      IF ok THEN
+  397        Adv;
+  398        M2S.GetName(M2S.nextPos, M2S.nextLen, nm);
+  399        IF (sym = 0) OR NOT SymTab.Equal(nm, pn) THEN ok := FALSE END
+  400      END;
+  401      IF ok THEN NoteSpan(pn, start) END;
+  402      sok := TRUE;
+  403      IF ok THEN
+  404        M2S.SeekTo(start);
+  405        Adv;
+  406        IF (sym # savedSym) OR (M2S.nextPos # start) THEN sok := FALSE END
+  407      END;
+  408      M2S.PopPos;
+  409      sym := savedSym; errDist := savedErr;
+  410      IF NOT ok THEN
+  411        FileIO.WriteString(FileIO.StdOut, "twophase probe mismatch in ");
+  412        FileIO.WriteString(FileIO.StdOut, pn);
+  413        FileIO.WriteLn(FileIO.StdOut)
+  414      ELSIF NOT sok THEN
+  415        FileIO.WriteString(FileIO.StdOut, "twophase seek mismatch in ");
+  416        FileIO.WriteString(FileIO.StdOut, pn);
+  417        FileIO.WriteLn(FileIO.StdOut)
+  418      END
+  419    END ProbeBody;
+  420  
+  421  CHARACTERS
+  422    eol      = CHR(13) .
+  423    lf       = CHR(10) .
+  424    letter   = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" .
+  425    digit    = "0123456789" .
+  426    hexDigit = digit + "ABCDEFabcdef" .
+  427    noQuote1 = ANY - "'" - eol .
+  428    noQuote2 = ANY - '"' - eol .
+  429  
+  430  IGNORE CHR(9) .. CHR(13)
+  431  
+  432  COMMENTS FROM "(*" TO "*)" NESTED
+  433  COMMENTS FROM "//" TO lf
+  434  
+  435  TOKENS
+  436    ident   = letter { letter | digit | "_" } .
+  437    integer = digit { digit }
+  438            | digit { digit } CONTEXT("..")
+  439            | "0x" hexDigit { hexDigit }
+  440            | "0X" hexDigit { hexDigit } .
+  441    real    = digit { digit } "." { digit }
+  442              [ ( "E" | "e" ) [ "+" | "-" ] digit { digit } ] .
+  443    string  = "'" { noQuote1 } "'"
+  444            | '"' { noQuote2 } '"' .
+  445    charConst = digit { digit } ( "C" | "c" ) .
+  446    ustring = ( "U" | "u" ) ( "'" { noQuote1 } "'" | '"' { noQuote2 } '"' ) .
+  447  
+  448  PRODUCTIONS
+  449    M2
+  450      = (. twoPhase := TRUE; astCur := AST.NoNode; astStmt := AST.NoNode; astDecl := AST.NoNode; astImp := AST.NoNode; astImpTail := AST.NoNode;
+  451                                             astImp := AST.NoNode;
+  452                                             astImpTail := AST.NoNode;
+  453                                             procNest := 0; nSpans := 0; .)
+  454        Unit "." .
+  455    (* Units: program modules compile fully; DEFINITION and
+  456       IMPLEMENTATION modules parse + check now but lower in step 4
+  457       (each ends with one 230); same for nested local modules. *)
+  458    (* Generics (Increment 1): formal and actual parameters.  Formals are
+  459       TYPE parameters only; actuals are type identifiers. *)
+  460    GenericFormals
+  461      = "(" GenericFormal { ";" GenericFormal } ")" .
+  462    GenericFormal                         (. VAR nm: SymTab.Name; .)
+  463      = GetIdent<nm>                      (. IF instActive THEN
+  464                                               IF NOT SymTab.EnterTypeParamBound(nm,
+  465                                                  InstActualGet(instFk)) THEN
+  466                                                 SemError(200) END
+  467                                             ELSIF NOT SymTab.EnterTypeParam(nm) THEN
+  468                                               SemError(200) END;
+  469                                             INC(instFk); .)
+  470        { "," GetIdent<nm>                (. IF instActive THEN
+  471                                               IF NOT SymTab.EnterTypeParamBound(nm,
+  472                                                  InstActualGet(instFk)) THEN
+  473                                                 SemError(200) END
+  474                                             ELSIF NOT SymTab.EnterTypeParam(nm) THEN
+  475                                               SemError(200) END;
+  476                                             INC(instFk); .) }
+  477        ":" "TYPE" .
+  478    Actuals
+  479      = Actual { "," Actual } .
+  480    Actual                                (. VAR at: SymTab.TypeIndex; .)
+  481      = TypeIdent<at>                     (. IF refN <= HIGH(refActual) THEN
+  482                                               refActual[refN] := at; INC(refN)
+  483                                             END; .) .
+  484    Unit
+  485      =                                   (. isGen := FALSE; .)
+  486        [ "GENERIC"                       (. isGen := TRUE; .) ]
+  487        ( DefUnit | ImplUnit | ProgModule ) .
+  488    (* Step 4.3: one session compiles DEFINITION, its IMPLEMENTATION
+  489       and one program (last) into one image. Units share the symbol
+  490       table; imports materialize exported names. *)
+  491    DefUnit                               (. VAR m1, m2, pn: SymTab.Name;
+  492                                               g: SymTab.Name;
+  493                                               astSeq, astTail, astProc: AST.Node; .)
+  494      =                                   (. refN := 0; refSeen := FALSE; .)
+  495        "DEFINITION" "MODULE"
+  496        GetIdent<m1>                      (. IF instActive THEN InstNameGet(m1) END;
+  497                                             IF instActive THEN
+  498                                               IF NOT SymTab.Reenter(m1,
+  499                                                      SymTab.UnitDef) THEN
+  500                                                 SemError(200) END
+  501                                             ELSIF NOT SymTab.BeginDef(m1) THEN
+  502                                               SemError(200) END;
+  503                                             QbeGen.SetModule(m1);
+  504                                             CopyNm(m1, unitName);
+  505                                             unitWasGen := isGen
+  506                                               AND NOT instActive;
+  507                                             unitWasDef := TRUE; .)
+  508        [ GenericFormals ]
+  509        ( ";"
+  510        { Import                        (. AstAppend(AST.NkDeclSeq,
+  511                                               astImp, astImpTail, astDecl); .) }
+  512        [ "EXPORT" [ "QUALIFIED" ]        (. (* definition-module export
+  513                                                list: parsed, and the
+  514                                                names are already exported
+  515                                                by the module scope *) .)
+  516          GetIdent<pn> { "," GetIdent<pn> } ";" ]
+  517                                          (. astSeq := AST.NoNode;
+  518                                             astTail := AST.NoNode; .)
+  519        { ConstBlock                      (. AstAppend(AST.NkDeclSeq,
+  520                                               astSeq, astTail, astDecl); .)
+  521        | TypeBlock<TRUE>                 (. AstAppend(AST.NkDeclSeq,
+  522                                               astSeq, astTail, astDecl); .)
+  523        | VarBlock                        (. AstAppend(AST.NkDeclSeq,
+  524                                               astSeq, astTail, astDecl); .)
+  525        | ProcHeading<pn, SymTab.InvalidType> ";"
+  526                                          (. (* a heading only: record it so
+  527                                                Lower can replay it *)
+  528                                             astProc := AST.MakeNode(AST.NkProcDecl);
+  529                                             AST.SetOp(astProc, 0);
+  530                                             AST.SetChild(astProc, 0,
+  531                                               AST.MakeLeaf(AST.NkIdent, pn));
+  532                                             AstAppend(AST.NkDeclSeq,
+  533                                               astSeq, astTail, astProc);
+  534                                             Lower.NoteProcNode(astProc);
+  535                                             Lower.ScopeLeave;
+  536                                             SymTab.CloseProc;
+  537                                             QbeGen.AbortFunc; .) }
+  538                                          (. astUnit := AST.MakeNode(AST.NkUnit);
+  539                                             AST.SetChild(astUnit, 0,
+  540                                               AST.MakeLeaf(AST.NkIdent, m1));
+  541                                             AST.SetChild(astUnit, 1, astSeq);
+  542                                             AST.SetChild(astUnit, 3, astImp);
+  543                                             astDecl := AST.NoNode;
+  544                                             astStmt := AST.NoNode; .)
+  545        "END"
+  546        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
+  547                                             IF NOT SymTab.Equal(m1, m2) THEN
+  548                                               SemError(202) END;
+  549                                             SymTab.EndUnit; .)
+  550        | "=" GetIdent<g> [ "(" Actuals ")" ] ";"
+  551                                          (. CopyNm(m1, refInst);
+  552                                             CopyNm(g, refGen);
+  553                                             refSeen := TRUE; refIsDef := TRUE;
+  554                                             astUnit := AST.MakeNode(AST.NkUnit);
+  555                                             AST.SetChild(astUnit, 0,
+  556                                               AST.MakeLeaf(AST.NkIdent, m1));
+  557                                             astDecl := AST.NoNode;
+  558                                             astStmt := AST.NoNode; .)
+  559          "END"
+  560          GetIdent<m2>                    (. IF NOT SymTab.Equal(m1, m2) THEN
+  561                                               SemError(202) END;
+  562                                             SymTab.EndUnit; .) ) .
+  563    ImplUnit                              (. VAR m1, m2: SymTab.Name;
+  564                                               g: SymTab.Name;
+  565                                               k: CARDINAL;
+  566                                               fname: SymTab.Name;
+  567                                               unres: BOOLEAN;
+  568                                               astNode: AST.Node; .)
+  569      =                                   (. refN := 0; refSeen := FALSE; .)
+  570        "IMPLEMENTATION" "MODULE"
+  571        GetIdent<m1> (. IF instActive THEN InstNameGet(m1) END;
+  572                       IF instActive THEN
+  573                         IF NOT SymTab.Reenter(m1,
+  574                                SymTab.UnitImpl) THEN
+  575                           SemError(201) END
+  576                       ELSIF NOT SymTab.BeginImpl(m1) THEN
+  577                         SemError(201) END;
+  578                       astStmt := AST.NoNode;
+  579                       astDecl := AST.NoNode;
+  580                       astImp := AST.NoNode;
+  581                       astImpTail := AST.NoNode;
+  582                       nPendVar := 0;
+  583                       CopyNm(m1, unitName);
+  584                       unitWasGen := isGen AND NOT instActive;
+  585                       unitWasDef := FALSE;
+  586                       QbeGen.SetModule(m1); .)
+  587        [ GenericFormals ]
+  588        ( ";"
+  589        { Import                        (. AstAppend(AST.NkDeclSeq,
+  590                                               astImp, astImpTail, astDecl); .) }
+  591        DeclSeq                           (. astStmt := AST.NoNode; .)
+  592        [ "BEGIN"                         (. FlushPend;
+  593                                             k := 0;
+  594                                             WHILE k < SymTab.FwdPending() DO
+  595                                               SymTab.FwdInfo(k, fname, unres);
+  596                                               IF unres THEN SemError(201) END;
+  597                                               INC(k)
+  598                                             END;
+  599                                             SymTab.FwdClear;
+  600  
+  601                                             nLab := 0; nGot := 0; .)
+  602          [ StatSeq ] ]
+  603        "END"
+  604        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
+  605                                             FlushPend;
+  606                                             k := 0;
+  607                                             WHILE k < SymTab.FwdPending() DO
+  608                                               SymTab.FwdInfo(k, fname, unres);
+  609                                               IF unres THEN SemError(201) END;
+  610                                               INC(k)
+  611                                             END;
+  612                                             SymTab.FwdClear;
+  613  
+  614                                             astNode := AST.MakeNode(AST.NkUnit);
+  615                                             AST.SetChild(astNode, 0,
+  616                                               AST.MakeLeaf(AST.NkIdent, m1));
+  617                                             AST.SetChild(astNode, 1, astDecl);
+  618                                             AST.SetChild(astNode, 2, astStmt);
+  619                                             AST.SetChild(astNode, 3, astImp);
+  620                                             astUnit := astNode;
+  621                                             IF NOT SymTab.Equal(m1, m2) THEN
+  622                                               SemError(202) END;
+  623                                             CheckGotos;
+  624                                             SymTab.EndUnit; .)
+  625        | "=" GetIdent<g> [ "(" Actuals ")" ] ";"
+  626                                          (. CopyNm(m1, refInst);
+  627                                             CopyNm(g, refGen);
+  628                                             refSeen := TRUE; refIsDef := FALSE;
+  629                                             astNode := AST.MakeNode(AST.NkUnit);
+  630                                             AST.SetChild(astNode, 0,
+  631                                               AST.MakeLeaf(AST.NkIdent, m1));
+  632                                             astDecl := AST.NoNode;
+  633                                             astStmt := AST.NoNode; .)
+  634          "END"
+  635          GetIdent<m2>                    (. IF NOT SymTab.Equal(m1, m2) THEN
+  636                                               SemError(202) END;
+  637                                             SymTab.EndUnit; .) ) .
+  638    ProgModule                            (. VAR m1, m2: SymTab.Name;
+  639                                               k: CARDINAL;
+  640                                               fname: SymTab.Name;
+  641                                               unres: BOOLEAN;
+  642                                               astNode: AST.Node; .)
+  643      = "MODULE"
+  644        GetIdent<m1> (. IF NOT SymTab.BeginProg(m1) THEN
+  645                                               SemError(200) END;
+  646                                             astStmt := AST.NoNode;
+  647                                             astDecl := AST.NoNode;
+  648                                             astImp := AST.NoNode;
+  649                                             astImpTail := AST.NoNode;
+  650                                             nPendVar := 0;
+  651                                             QbeGen.SetModule(m1); .)
+  652        [ Priority ]
+  653        ";"
+  654        { Import                        (. AstAppend(AST.NkDeclSeq,
+  655                                               astImp, astImpTail, astDecl); .) }
+  656        DeclSeq                           (. astStmt := AST.NoNode; .)
+  657        [ "BEGIN"                         (. FlushPend;
+  658                                             k := 0;
+  659                                             WHILE k < SymTab.FwdPending() DO
+  660                                               SymTab.FwdInfo(k, fname, unres);
+  661                                               IF unres THEN SemError(201) END;
+  662                                               INC(k)
+  663                                             END;
+  664                                             SymTab.FwdClear;
+  665  
+  666                                             nLab := 0; nGot := 0; .)
+  667          [ StatSeq ] ]
+  668        "END"
+  669        GetIdent<m2>                      (. IF instActive THEN InstNameGet(m2) END;
+  670                                             FlushPend;
+  671                                             k := 0;
+  672                                             WHILE k < SymTab.FwdPending() DO
+  673                                               SymTab.FwdInfo(k, fname, unres);
+  674                                               IF unres THEN SemError(201) END;
+  675                                               INC(k)
+  676                                             END;
+  677                                             SymTab.FwdClear;
+  678  
+  679                                             IF NOT SymTab.Equal(m1, m2) THEN
+  680                                               SemError(202) END;
+  681                                             astNode := AST.MakeNode(AST.NkUnit);
+  682                                             AST.SetChild(astNode, 0,
+  683                                               AST.MakeLeaf(AST.NkIdent, m1));
+  684                                             AST.SetChild(astNode, 1, astDecl);
+  685                                             AST.SetChild(astNode, 2, astStmt);
+  686                                             AST.SetChild(astNode, 3, astImp);
+  687                                             astUnit := astNode;
+  688                                             CheckGotos;
+  689                                             SymTab.EndUnit; .) .
+  690    DeclSeq                               (. VAR astSeq, astTail: AST.Node; .)
+  691      =                                   (. astSeq := AST.NoNode;
+  692                                             astTail := AST.NoNode; .)
+  693        { (. astDecl := AST.NoNode; .)
+  694          ( ConstBlock | TypeBlock<FALSE> | VarBlock | ProcDecl ";"
+  695          | NestedModule ";" | ClassItem ";" )
+  696                                          (. AstAppend(AST.NkDeclSeq,
+  697                                               astSeq, astTail, astDecl); .) }
+  698                                          (. astDecl := astSeq; .) .
+  699    (* Local module, Wirth form. Declarations lower like top-level ones
+  700       (same QBE module prefix); a BEGIN body becomes an init function
+  701       that main calls; the EXPORT list is hoisted into the enclosing
+  702       scope at END. *)
+  703    NestedModule                          (. VAR m1, m2: SymTab.Name;
+  704                                               expNames: ARRAY [0 .. 63] OF SymTab.Name;
+  705                                               expCount, k: CARDINAL;
+  706                                               astNode, nImp, nImpTail:
+  707                                                 AST.Node; .)
+  708      = "MODULE"
+  709        GetIdent<m1>                      (. IF NOT SymTab.Enter(m1,
+  710                                               SymTab.KindModule) THEN
+  711                                               SemError(200) END;
+  712                                             SymTab.PushScope;
+  713                                             expCount := 0;
+  714                                             astNode := AST.MakeNode(AST.NkUnit);
+  715                                             AST.SetChild(astNode, 0,
+  716                                               AST.MakeLeaf(AST.NkIdent, m1));
+  717                                             astStmt := AST.NoNode;
+  718                                             astDecl := AST.NoNode;
+  719                                             nImp := AST.NoNode;
+  720                                             nImpTail := AST.NoNode; .)
+  721        [ Priority ]
+  722        ";"
+  723        { Import                        (. AstAppend(AST.NkDeclSeq,
+  724                                               nImp, nImpTail, astDecl); .) }
+  725        [ "EXPORT" [ "QUALIFIED" ]
+  726          GetIdent<expNames[expCount]>    (. INC(expCount); .)
+  727          { "," GetIdent<expNames[expCount]>
+  728                                          (. INC(expCount); .) }
+  729          ";" ]
+  730        DeclSeq                           (. astStmt := AST.NoNode; .)
+  731        [ "BEGIN"                         (. astStmt := AST.NoNode;
+  732                                             .)
+  733          [ StatSeq ] ]
+  734        "END"
+  735        GetIdent<m2>                      (. AST.SetChild(astNode, 1, astDecl);
+  736                                             AST.SetChild(astNode, 2, astStmt);
+  737                                             AST.SetChild(astNode, 3, nImp);
+  738                                             astDecl := astNode;
+  739                                             IF NOT SymTab.Equal(m1, m2) THEN
+  740                                               SemError(202) END;
+  741                                             k := 0;
+  742                                             WHILE k < expCount DO
+  743                                               SymTab.ExportUp(expNames[k]);
+  744                                               INC(k)
+  745                                             END;
+  746                                             SymTab.PopScope; .) .
+  747    Priority
+  748      = "[" integer "]"                   (. SemError(230); .) .
+  749    (* Imports (4.3): FROM materializes the names (unqualified use);
+  750       plain IMPORT only demands the module exists — qualified `L.x`
+  751       materializes on first use (Design). *)
+  752    (* Unknown modules stay unchecked stubs (legacy, so hand-written
+  753       import lines don't fail); a known module's missing export is
+  754       201. *)
+  755    Import                                (. VAR n: SymTab.Name;
+  756                                               astImport: AST.Node; .)
+  757      = "FROM"
+  758        GetIdent<n>                       (. astImport := AST.MakeNode(AST.NkImport);
+  759                                             AST.SetChild(astImport, 0,
+  760                                               AST.MakeLeaf(AST.NkIdent, n)); .)
+  761        "IMPORT"
+  762        ImpList<n, astImport> ";"         (. astDecl := astImport; .)
+  763      | "IMPORT"                          (. astImport := AST.MakeNode(AST.NkImport); .)
+  764        ImpModList<astImport> ";"         (. astDecl := astImport; .) .
+  765    ImpList<mod: SymTab.Name; node: AST.Node>
+  766                                          (. VAR n: SymTab.Name; .)
+  767      = ImpName<mod, node>
+  768        { "," ImpName<mod, node> } .
+  769    (* Pervasive built-ins imported from SYSTEM (e.g. TSIZE) are
+  770       accepted and ignored: the built-in applies regardless. *)
+  771    ImpName<mod: SymTab.Name; node: AST.Node>
+  772                                          (. VAR n: SymTab.Name; .)
+  773      = GetIdent<n> (. AST.SetChild(node, AST.NChild(node),
+  774                                               AST.MakeLeaf(AST.NkIdent, n));
+  775                                             IF SymTab.Equal(mod, "libc") THEN
+  776                                               (* intrinsic C library:
+  777                                                  permissive external *)
+  778                                               IF NOT SymTab.DeclareCProc(n) THEN
+  779                                                 SemError(201) END;
+  780                                               Lower.NoteCProc(n)
+  781                                             ELSIF SymTab.ModKnown(mod) THEN
+  782                                               IF NOT SymTab.ImportFrom(mod, n) THEN
+  783                                                 SemError(201)
+  784                                               ELSE Lower.NoteImportedProc(n)
+  785                                               END
+  786                                             END; .)
+  787      | ( "TSIZE" | "SIZE" | "ADR" | "HIGH" | "LEN"
+  788        | "CHR" | "ORD" | "ORDL" | "VAL" | "ABS" | "CAP"
+  789        | "UCHR" | "CHR8" | "UORD"
+  790        | "INC" | "DEC" ) .
+  791    ImpModList<node: AST.Node>            (. VAR n: SymTab.Name; .)
+  792      = GetIdent<n>                       (. AST.SetChild(node, AST.NChild(node),
+  793                                               AST.MakeLeaf(AST.NkIdent, n)); .)
+  794        { "," GetIdent<n>                 (. AST.SetChild(node, AST.NChild(node),
+  795                                               AST.MakeLeaf(AST.NkIdent, n)); .) } .
+  796    (* Opaque TYPE declarations (definition modules). The targetless
+  797       alias resolves to InvalidType until step 4 completes it. *)
+  798    (* Scalar-phase TYPEs: named types, integer subranges, enumerations.
+  799       Opaque "TYPE T;" needs isDef (definition units); elsewhere 231.
+  800       Composite forms (ARRAY/RECORD/SET/POINTER) arrive with step 3. *)
+  801    TypeBlock<isDef: BOOLEAN>             (. VAR astSeq, astTail: AST.Node; .)
+  802      = "TYPE"                            (. SymTab.BeginTypeBlock;
+  803                                             astSeq := AST.NoNode;
+  804                                             astTail := AST.NoNode; .)
+  805        { (. astDecl := AST.NoNode; .)
+  806          ( TypeItem<isDef> ";" | ClassItem ";" )
+  807                                          (. AstAppend(AST.NkDeclSeq,
+  808                                               astSeq, astTail, astDecl); .) }
+  809                                          (. SymTab.EndTypeBlock;
+  810                                             astDecl := astSeq; .) .
+  811    TypeItem<isDef: BOOLEAN>              (. VAR n: SymTab.Name;
+  812                                               t, op: SymTab.TypeIndex;
+  813                                               astNode: AST.Node; .)
+  814      = GetIdent<n>                       (. op := SymTab.OpaqueBase(n);
+  815                                             IF op = SymTab.InvalidType THEN
+  816                                               IF NOT SymTab.Enter(n,
+  817                                                  SymTab.KindType) THEN
+  818                                                 SemError(200) END
+  819                                             END; .)
+  820        ( "=" Type<t, FALSE> (. astNode := AST.MakeNode(AST.NkTypeDecl);
+  821                                               AST.SetChild(astNode, 0,
+  822                                                 AST.MakeLeaf(AST.NkIdent, n));
+  823                                               AST.SetTy(astNode, t);
+  824                                               astDecl := astNode;
+  825                                               IF op # SymTab.InvalidType THEN
+  826                                               SymTab.SetTarget(op, t)
+  827                                             ELSE SymTab.SetSymType(n, t)
+  828                                             END; .)
+  829        |                                 (. IF op # SymTab.InvalidType THEN
+  830                                               (* stays opaque *)
+  831                                             ELSIF NOT isDef THEN
+  832                                               SemError(231)
+  833                                             ELSE SymTab.SetSymType(n,
+  834                                               SymTab.NewAlias()) END; .) ) .
+  835    Type<VAR t: SymTab.TypeIndex; allowOpen: BOOLEAN>
+  836      = TypeIdent<t> [ Subrange<t> ]     (* anchored subrange: T[lo..hi] *)
+  837      | Subrange<t>
+  838      | Enum<t>
+  839      | ArrayType<t, allowOpen>
+  840      | SetType<t>
+  841      | RecordType<t>
+  842      | PointerType<t>
+  843      | ProcType<t> .
+  844    PointerType<VAR t: SymTab.TypeIndex>  (. VAR base: SymTab.TypeIndex; .)
+  845      = "POINTER" "TO" Type<base, FALSE>(. t := SymTab.NewPtr(base); .) .
+  846    (* Procedure types (step 8.5): PROCEDURE (params): result. Values
+  847       are code pointers; params are collected into the descriptor. *)
+  848    ProcType<VAR t: SymTab.TypeIndex>     (. VAR res, pt: SymTab.TypeIndex;
+  849                                               isV: BOOLEAN; .)
+  850      = "PROCEDURE"                       (. res := SymTab.InvalidType;
+  851                                             t := SymTab.NewProcType(res); .)
+  852        [ "(" [ ProcTypeSection<t> { ";" ProcTypeSection<t> } ] ")" ]
+  853        [ ":" TypeIdent<res>              (. SymTab.SetProcTypeRes(t, res); .) ] .
+  854    ProcTypeSection<t: SymTab.TypeIndex>  (. VAR pt: SymTab.TypeIndex;
+  855                                               isV: BOOLEAN;
+  856                                               cnt, k: CARDINAL;
+  857                                               names: ARRAY [0 .. 15] OF SymTab.Name; .)
+  858      =                                   (. isV := FALSE; cnt := 0; .)
+  859        [ "VAR"                           (. isV := TRUE; .) ]
+  860        ( GetIdent<names[cnt]>            (. INC(cnt); .)
+  861          { "," GetIdent<names[cnt]>      (. INC(cnt); .) }
+  862          ( ":" Type<pt, TRUE>           (. k := 0;
+  863                                             WHILE k < cnt DO
+  864                                               SymTab.ProcTypeAdd(t, isV, pt);
+  865                                               INC(k)
+  866                                             END; .)
+  867          |                               (. (* type-only parameter list:
+  868                                                each name is a type (GNU
+  869                                                shorthand used by the
+  870                                                Coco/R scanner frame) *)
+  871                                             k := 0;
+  872                                             WHILE k < cnt DO
+  873                                               IF SymTab.Lookup(names[k])
+  874                                                  AND ((SymTab.SymKind(names[k]) = SymTab.KindType)
+  875    OR (SymTab.SymKind(names[k]) = SymTab.KindPredef)) THEN
+  876                                                 pt := SymTab.SymType(names[k])
+  877                                               ELSE SemError(201);
+  878                                                 pt := SymTab.InvalidType
+  879                                               END;
+  880                                               SymTab.ProcTypeAdd(t, isV, pt);
+  881                                               INC(k)
+  882                                             END; .) )
+  883        | Type<pt, TRUE>                 (. (* unnamed parameter (PIM):
+  884                                                e.g. PROCEDURE (VAR ARRAY OF REAL) *)
+  885                                             SymTab.ProcTypeAdd(t, isV, pt); .) ) .
+  886    (* Arrays: "OF" without bounds is an open formal (allowed only
+  887       where allowOpen); "[lo..hi, ...]" nests bounded levels inside
+  888       out. Bounds are folded literals (int/char); anything else 230.
+  889       Bare-type indices ("ARRAY Color OF") wait for enum ordinals. *)
+  890    ArrayType<VAR t: SymTab.TypeIndex; allowOpen: BOOLEAN>
+  891                                          (. VAR elem: SymTab.TypeIndex;
+  892                                               ok: BOOLEAN;
+  893                                               bnds, bndh: ARRAY [0 .. 7] OF INTEGER;
+  894                                               nb, k: CARDINAL;
+  895                                               idx: SymTab.TypeIndex;
+  896                                               ilo, ihi: INTEGER; .)
+  897      = "ARRAY"
+  898        ( "OF" Type<elem, FALSE>          (. IF NOT allowOpen THEN
+  899                                               SemError(230) END;
+  900                                             t := SymTab.NewOpenArray(elem); .)
+  901        | TypeIdent<idx> [ Subrange<idx> ]
+  902          "OF" Type<elem, FALSE>          (. (* index-type array: the index
+  903                                                type's ordinal bounds give the
+  904                                                [lo..hi] pair *)
+  905                                             IF SymTab.TypeBounds(idx, ilo,
+  906                                                ihi)
+  907                                             THEN t := SymTab.NewArrayB(elem,
+  908                                                    ilo, ihi)
+  909                                             ELSE SemError(230);
+  910                                               t := SymTab.InvalidType
+  911                                             END; .)
+  912        | "["                             (. SymTab.BoundBegin; ok := TRUE; .)
+  913          BoundPair<ok>
+  914          { "," BoundPair<ok> }
+  915          "]"                             (. (* snapshot before the element
+  916                                                type, which reuses the bound
+  917                                                buffer for a nested ARRAY *)
+  918                                             nb := SymTab.BoundCount();
+  919                                             k := 0;
+  920                                             WHILE k < nb DO
+  921                                               bnds[k] := SymTab.BoundLo(k);
+  922                                               bndh[k] := SymTab.BoundHi(k);
+  923                                               INC(k)
+  924                                             END; .)
+  925          "OF" Type<elem, FALSE>
+  926                                          (. IF ok THEN
+  927                                               k := nb;
+  928                                               WHILE k > 0 DO
+  929                                                 DEC(k);
+  930                                                 elem := SymTab.NewArrayB(
+  931                                                   elem, bnds[k], bndh[k])
+  932                                               END;
+  933                                               t := elem
+  934                                             ELSE t := SymTab.InvalidType
+  935                                             END; .) ) .
+  936    BoundPair<VAR ok: BOOLEAN>            (. VAR tlo, thi: SymTab.TypeIndex;
+  937                                               qlo, qhi: QbeGen.QVal;
+  938                                               lo, hi: INTEGER;
+  939                                               cl, cl2: INTEGER; .)
+  940      = Expr<tlo, qlo> ".." Expr<thi, qhi>
+  941                                          (. IF (tlo = SymTab.InvalidType)
+  942                                              OR (thi = SymTab.InvalidType) THEN
+  943                                             ok := FALSE
+  944                                           ELSE cl := SymTab.ClassOf(tlo);
+  945                                             cl2 := SymTab.ClassOf(thi);
+  946                                             IF ((cl # SymTab.ClInt)
+  947   AND (cl # SymTab.ClChar))
+  948                                                OR ((cl2 # SymTab.ClInt)
+  949   AND (cl2 # SymTab.ClChar)) THEN
+  950                                               SemError(230); ok := FALSE
+  951                                             ELSIF NOT SymTab.ConstInt(qlo, lo)
+  952                                                OR NOT SymTab.ConstInt(qhi, hi)
+  953                                                OR (lo > hi) THEN
+  954                                               SemError(230); ok := FALSE
+  955                                              ELSIF NOT SymTab.BoundAdd(lo, hi) THEN
+  956                                                SemError(230); ok := FALSE
+  957                                              END;
+  958                                            END; .) .
+  959    (* Sets: multi-word masks over bases ≤ 256 values (bool, char,
+  960       bounded subranges; enums wait for ordinals, INTEGER is
+  961       unbounded). Literals are SET OF [0..255]; assignment and
+  962       comparison across suitable bases are lenient (masks over min
+  963       words + zero-check extras), out-of-span literals are 222. *)
+  964    SetType<VAR t: SymTab.TypeIndex>      (. VAR base: SymTab.TypeIndex;
+  965                                               blo, bhi, bspan: INTEGER;
+  966                                               bcls: INTEGER; .)
+  967      = "SET" "OF" Type<base, FALSE>
+  968                                          (. IF base = SymTab.InvalidType THEN
+  969                                               t := SymTab.InvalidType
+  970                                             ELSE bcls :=
+  971                                                    SymTab.ClassOf(base);
+  972                                               IF bcls = SymTab.ClBool THEN
+  973                                                 blo := 0; bspan := 2
+  974                                               ELSIF bcls = SymTab.ClChar THEN
+  975                                                 blo := 0; bspan := 256
+  976                                               ELSIF bcls = SymTab.ClEnum THEN
+  977                                                 blo := 0;
+  978                                                 bspan := VAL(INTEGER,
+  979                                                   SymTab.EnumCount(base))
+  980                                               ELSIF SymTab.SubBounds(base,
+  981                                                       blo, bhi) THEN
+  982                                                 bspan := bhi - blo + 1
+  983                                               ELSE bspan := 0 END;
+  984                                               IF (bspan <= 0)
+  985                                                  OR (bspan > 65536) THEN
+  986                                                 SemError(230);
+  987                                                 t := SymTab.InvalidType
+  988                                               ELSE t := SymTab.NewSet(base)
+  989                                               END
+  990                                             END; .) .
+  991    (* Records: flat blobs; array fields are pointers to static
+  992       descriptors (locked amendment), nested records inline. Field
+  993       offsets static and declaration-ordered. *)
+  994    (* Field list: plain fields and (optionally) one variant part.  The
+  995       variant part is a `CASE ... END` item; because it starts with the
+  996       CASE keyword it is unambiguously distinguishable from a field
+  997       (which starts with an identifier). *)
+  998    RecordType<VAR t: SymTab.TypeIndex>   (. VAR t2: SymTab.TypeIndex;
+  999                                               tagOk: BOOLEAN; .)
+ 1000      = "RECORD"                          (. t := SymTab.NewRecord(); .)
+ 1001        [ RecItem<t> { ";" [ RecItem<t> ] } ]
+ 1002        "END"                             (. SymTab.LayoutRecord(t); .) .
+ 1003    RecItem<rec: SymTab.TypeIndex>        (. VAR tt: SymTab.TypeIndex; .)
+ 1004      = RecField<rec>
+ 1005      | CaseField<rec>                    (. SymTab.MarkVariant(rec); .) .
+ 1006    (* A variant part: CASE tag : Type OF variants.  The layout overlays
+ 1007       every branch from the tag slot (see SymTab.ComputeOffsets). *)
+ 1008    CaseField<rec: SymTab.TypeIndex>      (. VAR tagT: SymTab.TypeIndex;
+ 1009                                               tagN: SymTab.Name; .)
+ 1010      = "CASE"                            (. SymTab.ResetFields(rec); .)
+ 1011        GetIdent<tagN>                    (. IF NOT SymTab.FieldPending(rec,
+ 1012                                               tagN) THEN
  1013                                               SemError(200) END; .)
- 1014        { "," GetIdent<n>                 (. IF NOT SymTab.FieldPending(rec,
- 1015                                               n) THEN
- 1016                                               SemError(200) END; .) } .
- 1017    TypeIdent<VAR t: SymTab.TypeIndex>    (. VAR n, qid: SymTab.Name;
- 1018                                               k: INTEGER;
- 1019                                               dotted: BOOLEAN; .)
- 1020      = GetIdent<n>                       (. dotted := FALSE;
- 1021                                             IF NOT SymTab.Lookup(n) THEN
- 1022                                               k := -1;
- 1023                                               t := SymTab.ForwardType(n);
- 1024                                               IF t = SymTab.InvalidType THEN
- 1025                                                 SemError(201)
- 1026                                               END
- 1027                                             ELSE k := SymTab.SymKind(n);
- 1028                                               IF (k = SymTab.KindType)
- 1029                                                  OR (k = SymTab.KindPredef) THEN
- 1030                                                 t := SymTab.SymType(n)
- 1031                                               ELSE t := SymTab.InvalidType
- 1032                                               END
- 1033                                             END; .)
- 1034        [ "." GetIdent<qid>               (. dotted := TRUE;
- 1035                                             IF k = SymTab.KindModule THEN
- 1036                                               t := SymTab.QualType(n, qid);
- 1037                                               IF t = SymTab.InvalidType THEN
- 1038                                                 SemError(201)
- 1039                                               END
- 1040                                             ELSE SemError(221);
- 1041                                               t := SymTab.InvalidType
- 1042                                             END; .) ]
- 1043                                          (. IF NOT dotted THEN
- 1044                                               IF (k = SymTab.KindModule)
- 1045                                                  OR ((k # SymTab.KindType)
- 1046    AND (k # SymTab.KindPredef)
- 1047    AND (k # SymTab.KindImport)
- 1048    AND (k # -1)) THEN
- 1049                                                 SemError(221)
- 1050                                               END
- 1051                                             END; .) .
- 1052    Subrange<VAR t: SymTab.TypeIndex>     (. VAR tlo, thi: SymTab.TypeIndex;
- 1053                                               qlo, qhi: QbeGen.QVal;
- 1054                                               lo, hi: INTEGER; .)
- 1055      = "[" Expr<tlo, qlo> ".." Expr<thi, qhi>
- 1056                                          (. IF (tlo = SymTab.InvalidType)
- 1057                                              OR (thi = SymTab.InvalidType) THEN
- 1058                                             t := SymTab.InvalidType
- 1059                                           ELSIF NOT SymTab.IsOrdinal(tlo)
- 1060                                              OR NOT SymTab.IsOrdinal(thi) THEN
- 1061                                             SemError(230);
- 1062                                             t := SymTab.InvalidType
- 1063                                           ELSIF NOT SymTab.ConstInt(qlo, lo)
- 1064                                              OR NOT SymTab.ConstInt(qhi, hi)
- 1065                                              OR (lo > hi) THEN
- 1066                                             SemError(230);
- 1067                                             t := SymTab.InvalidType
- 1068                                           ELSE t := SymTab.NewSubR(lo, hi)
- 1069                                           END; .)
- 1070        "]" .
- 1071    Enum<VAR t: SymTab.TypeIndex>         (. VAR n: SymTab.Name;
- 1072                                               ord: INTEGER;
- 1073                                               qv: QbeGen.QVal; .)
- 1074      = "("                               (. t := SymTab.NewEnum();
- 1075                                             ord := 0; .)
- 1076        GetIdent<n>                       (. IF NOT SymTab.Enter(n,
- 1077                                               SymTab.KindConst) THEN
- 1078                                               SemError(200) END;
- 1079                                             SymTab.SetSymType(n, t);
- 1080                                             QbeGen.IntStr(ord, qv);
- 1081                                             SymTab.SetSymVal(n, qv);
- 1082                                             Lower.NoteVar(n,
- 1083                                               SymTab.KindConst, t);
- 1084                                             Lower.NoteConstVal(qv);
- 1085                                             INC(ord); .)
- 1086        { "," GetIdent<n>                 (. IF NOT SymTab.Enter(n,
- 1087                                               SymTab.KindConst) THEN
- 1088                                               SemError(200) END;
- 1089                                             SymTab.SetSymType(n, t);
- 1090                                             QbeGen.IntStr(ord, qv);
- 1091                                             SymTab.SetSymVal(n, qv);
- 1092                                             Lower.NoteVar(n,
- 1093                                               SymTab.KindConst, t);
- 1094                                             Lower.NoteConstVal(qv);
- 1095                                             INC(ord); .) }
- 1096        ")"                               (. SymTab.SetEnumCount(t,
- 1097                                               VAL(CARDINAL, ord)); .) .
- 1098    (* Clarion-form classes (docs/OOP.txt): declaration + single
- 1099       inheritance + IMPLEMENTATION blocks. Scopes and member checks
- 1100       now; lowering (vtable, dispatch, THIS) later — one 230 per
- 1101       class/impl block. Methods end with ";" per the Table example
- 1102       (not "," as in the sketch). No underscores in identifiers. *)
- 1103    (* Single CLASS item in both loops: separating declaration from
- 1104       IMPLEMENTATION at the loop level needs 2-token lookahead
- 1105       (CLASS ident vs CLASS IMPLEMENTATION), which LL(1) cannot do.
- 1106       The second token decides after CLASS is consumed. A misplaced
- 1107       CLASS IMPLEMENTATION inside TYPE still parses (harmless: the
- 1108       whole unit ends 230 until lowering). *)
- 1109    ClassItem
- 1110      = "CLASS" ( "IMPLEMENTATION" ClassImplRest | ClassRest ) .
- 1111    ClassRest                             (. VAR cn, m2, pn: SymTab.Name;
- 1112                                               ct: SymTab.TypeIndex; .)
- 1113      = GetIdent<cn>                      (. IF NOT SymTab.Enter(cn,
- 1114                                               SymTab.KindType) THEN
- 1115                                               SemError(200) END;
- 1116                                             ct := SymTab.NewClass();
- 1117                                             SymTab.SetSymType(cn, ct);
- 1118                                             SymTab.PushClassScope(ct);
- 1119                                             astCls := AST.MakeNode(AST.NkClassDecl);
- 1120                                             AST.SetChild(astCls, 0,
- 1121                                               AST.MakeLeaf(AST.NkIdent, cn));
- 1122                                             astClsP := AST.NoNode;
- 1123                                             astClsPTail := AST.NoNode;
- 1124                                             astClsF := AST.NoNode;
- 1125                                             astClsFTail := AST.NoNode;
- 1126                                             astClsM := AST.NoNode;
- 1127                                             astClsMTail := AST.NoNode; .)
- 1128        [ Parents<ct> ]
- 1129        ";"
- 1130        { ClassField<ct> ";" }
- 1131        { MethodHeading<pn, SymTab.InvalidType> ";"
- 1132                                          (. Lower.ScopeLeave;
- 1133                                             SymTab.CloseProc;
- 1134                                             QbeGen.AbortFunc; .) }
- 1135        "END"
- 1136        GetIdent<m2>                      (. IF NOT SymTab.Equal(cn, m2) THEN
- 1137                                               SemError(202) END;
- 1138                                             SymTab.LayoutClass(ct);
- 1139                                             SymTab.PopScope;
- 1140                                             AST.SetChild(astCls, 1, astClsP);
- 1141                                             AST.SetChild(astCls, 2, astClsF);
- 1142                                             AST.SetChild(astCls, 3, astClsM);
- 1143                                             astDecl := astCls; .) .
- 1144    Parents<ct: SymTab.TypeIndex>         (. VAR p: SymTab.Name; .)
- 1145      = "(" Parent1<ct>
- 1146        { "," GetIdent<p>                 (. SemError(230); .) }
- 1147        ")" .
- 1148    Parent1<ct: SymTab.TypeIndex>         (. VAR p: SymTab.Name;
- 1149                                               pt: SymTab.TypeIndex; .)
- 1150      = GetIdent<p>                       (. IF NOT SymTab.Lookup(p) THEN
- 1151                                               SemError(201)
- 1152                                             ELSE pt := SymTab.SymType(p);
- 1153                                               IF SymTab.ClassOf(pt) #
- 1154                                                  SymTab.ClClass THEN
- 1155                                                 SemError(230)
- 1156                                               ELSE SymTab.SetParent(ct, pt)
- 1157                                               END
- 1158                                             END;
- 1159                                             AstAppend(AST.NkFieldDecl,
- 1160                                               astClsP, astClsPTail,
- 1161                                               AST.MakeLeaf(AST.NkIdent, p)); .) .
- 1162    ClassField<ct: SymTab.TypeIndex>      (. VAR n, rhs: SymTab.Name;
- 1163                                               t: SymTab.TypeIndex;
- 1164                                               astNode: AST.Node; .)
- 1165      = GetIdent<n>
- 1166        ( "=" GetIdent<rhs>               (. IF NOT SymTab.Enter(n,
- 1167                                               SymTab.KindConst) THEN
- 1168                                               SemError(200) END;
- 1169                                             astNode := AST.MakeNode(AST.NkConstDecl);
- 1170                                             AST.SetChild(astNode, 0,
- 1171                                               AST.MakeLeaf(AST.NkIdent, n));
- 1172                                             AST.SetChild(astNode, 1,
- 1173                                               AST.MakeLeaf(AST.NkIdent, rhs));
- 1174                                             AstAppend(AST.NkFieldDecl,
- 1175                                               astClsF, astClsFTail, astNode);
- 1176                                             IF SymTab.Lookup(rhs) THEN
- 1177                                               SymTab.SetSymType(n,
- 1178                                                 SymTab.SymType(rhs))
- 1179                                             END; .)
- 1180        |                                 (. IF NOT SymTab.FieldPending(ct,
- 1181                                               n) THEN
- 1182                                               SemError(200) END;
- 1183                                             astNode := AST.MakeNode(AST.NkVarDecl);
- 1184                                             AST.SetChild(astNode, 0,
- 1185                                               AST.MakeLeaf(AST.NkIdent, n)); .)
- 1186          { "," GetIdent<n>               (. IF NOT SymTab.FieldPending(ct,
- 1187                                               n) THEN
- 1188                                               SemError(200) END;
- 1189                                             AST.SetChild(astNode,
- 1190                                               AST.NChild(astNode),
- 1191                                               AST.MakeLeaf(AST.NkIdent, n)); .) }
- 1192          ":" Type<t, FALSE>              (. SymTab.FixPendingF(ct, t);
- 1193                                             AST.SetTy(astNode, t);
+ 1014        ":" Type<tagT, FALSE>             (. IF (tagT # SymTab.InvalidType)
+ 1015    AND NOT SymTab.IsOrdinal(tagT) THEN
+ 1016                                               SemError(224)
+ 1017                                             END;
+ 1018                                             SymTab.FixPendingF(rec, tagT);
+ 1019                                             SymTab.SetVariantTag(rec, tagN); .)
+ 1020        "OF"
+ 1021        RecFieldList<rec>
+ 1022        { "|"                             (. SymTab.ResetFields(rec); .)
+ 1023          RecFieldList<rec> }
+ 1024        "END" .
+ 1025    RecFieldList<rec: SymTab.TypeIndex>   (. VAR lt, lq: SymTab.TypeIndex;
+ 1026                                               lv1, lv2: QbeGen.QVal; .)
+ 1027      = VarLabel<lt, lv1> [ ".." VarLabel<lq, lv2> ] ":"
+ 1028        RecField<rec> { ";" [ RecField<rec> ] } .
+ 1029    (* Variant case label: a constant (or a constant range).  Values are
+ 1030       not interpreted (the layout overlays regardless). *)
+ 1031    VarLabel<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 1032                                          (. VAR lname: SymTab.Name; .)
+ 1033      = ( ident                         (. LexName(lname);
+ 1034                                             QbeGen.CopyOp("0", q);
+ 1035                                             t := SymTab.IntType(); .)
+ 1036        | integer                       (. LexString(lname);
+ 1037                                             QbeGen.CopyOp("0", q);
+ 1038                                             t := SymTab.IntType(); .)
+ 1039        | charConst                     (. LexString(lname);
+ 1040                                             QbeGen.CopyOp("0", q);
+ 1041                                             t := SymTab.CharType(); .) ) .
+ 1042    RecField<rec: SymTab.TypeIndex>       (. VAR n: SymTab.Name;
+ 1043                                               t2: SymTab.TypeIndex; .)
+ 1044      = RecIdents<rec> ":" Type<t2, FALSE>(. SymTab.FixPendingF(rec, t2); .) .
+ 1045    RecIdents<rec: SymTab.TypeIndex>      (. VAR n: SymTab.Name; .)
+ 1046      = GetIdent<n>                       (. IF NOT SymTab.FieldPending(rec,
+ 1047                                               n) THEN
+ 1048                                               SemError(200) END; .)
+ 1049        { "," GetIdent<n>                 (. IF NOT SymTab.FieldPending(rec,
+ 1050                                               n) THEN
+ 1051                                               SemError(200) END; .) } .
+ 1052    TypeIdent<VAR t: SymTab.TypeIndex>    (. VAR n, qid: SymTab.Name;
+ 1053                                               k: INTEGER;
+ 1054                                               dotted: BOOLEAN; .)
+ 1055      = GetIdent<n>                       (. dotted := FALSE;
+ 1056                                             IF NOT SymTab.Lookup(n) THEN
+ 1057                                               k := -1;
+ 1058                                               t := SymTab.ForwardType(n);
+ 1059                                               IF t = SymTab.InvalidType THEN
+ 1060                                                 SemError(201)
+ 1061                                               END
+ 1062                                             ELSE k := SymTab.SymKind(n);
+ 1063                                               IF (k = SymTab.KindType)
+ 1064                                                  OR (k = SymTab.KindPredef) THEN
+ 1065                                                 t := SymTab.SymType(n)
+ 1066                                               ELSE t := SymTab.InvalidType
+ 1067                                               END
+ 1068                                             END; .)
+ 1069        [ "." GetIdent<qid>               (. dotted := TRUE;
+ 1070                                             IF k = SymTab.KindModule THEN
+ 1071                                               t := SymTab.QualType(n, qid);
+ 1072                                               IF t = SymTab.InvalidType THEN
+ 1073                                                 SemError(201)
+ 1074                                               END
+ 1075                                             ELSE SemError(221);
+ 1076                                               t := SymTab.InvalidType
+ 1077                                             END; .) ]
+ 1078                                          (. IF NOT dotted THEN
+ 1079                                               IF (k = SymTab.KindModule)
+ 1080                                                  OR ((k # SymTab.KindType)
+ 1081    AND (k # SymTab.KindPredef)
+ 1082    AND (k # SymTab.KindImport)
+ 1083    AND (k # -1)) THEN
+ 1084                                                 SemError(221)
+ 1085                                               END
+ 1086                                             END; .) .
+ 1087    Subrange<VAR t: SymTab.TypeIndex>     (. VAR tlo, thi: SymTab.TypeIndex;
+ 1088                                               qlo, qhi: QbeGen.QVal;
+ 1089                                               lo, hi: INTEGER; .)
+ 1090      = "[" Expr<tlo, qlo> ".." Expr<thi, qhi>
+ 1091                                          (. IF (tlo = SymTab.InvalidType)
+ 1092                                              OR (thi = SymTab.InvalidType) THEN
+ 1093                                             t := SymTab.InvalidType
+ 1094                                           ELSIF NOT SymTab.IsOrdinal(tlo)
+ 1095                                              OR NOT SymTab.IsOrdinal(thi) THEN
+ 1096                                             SemError(230);
+ 1097                                             t := SymTab.InvalidType
+ 1098                                           ELSIF NOT SymTab.ConstInt(qlo, lo)
+ 1099                                              OR NOT SymTab.ConstInt(qhi, hi)
+ 1100                                              OR (lo > hi) THEN
+ 1101                                             SemError(230);
+ 1102                                             t := SymTab.InvalidType
+ 1103                                           ELSE t := SymTab.NewSubR(lo, hi)
+ 1104                                           END; .)
+ 1105        "]" .
+ 1106    Enum<VAR t: SymTab.TypeIndex>         (. VAR n: SymTab.Name;
+ 1107                                               ord: INTEGER;
+ 1108                                               qv: QbeGen.QVal; .)
+ 1109      = "("                               (. t := SymTab.NewEnum();
+ 1110                                             ord := 0; .)
+ 1111        GetIdent<n>                       (. IF NOT SymTab.Enter(n,
+ 1112                                               SymTab.KindConst) THEN
+ 1113                                               SemError(200) END;
+ 1114                                             SymTab.SetSymType(n, t);
+ 1115                                             QbeGen.IntStr(ord, qv);
+ 1116                                             SymTab.SetSymVal(n, qv);
+ 1117                                             Lower.NoteVar(n,
+ 1118                                               SymTab.KindConst, t);
+ 1119                                             Lower.NoteConstVal(qv);
+ 1120                                             INC(ord); .)
+ 1121        { "," GetIdent<n>                 (. IF NOT SymTab.Enter(n,
+ 1122                                               SymTab.KindConst) THEN
+ 1123                                               SemError(200) END;
+ 1124                                             SymTab.SetSymType(n, t);
+ 1125                                             QbeGen.IntStr(ord, qv);
+ 1126                                             SymTab.SetSymVal(n, qv);
+ 1127                                             Lower.NoteVar(n,
+ 1128                                               SymTab.KindConst, t);
+ 1129                                             Lower.NoteConstVal(qv);
+ 1130                                             INC(ord); .) }
+ 1131        ")"                               (. SymTab.SetEnumCount(t,
+ 1132                                               VAL(CARDINAL, ord)); .) .
+ 1133    (* Clarion-form classes (docs/OOP.txt): declaration + single
+ 1134       inheritance + IMPLEMENTATION blocks. Scopes and member checks
+ 1135       now; lowering (vtable, dispatch, THIS) later — one 230 per
+ 1136       class/impl block. Methods end with ";" per the Table example
+ 1137       (not "," as in the sketch). No underscores in identifiers. *)
+ 1138    (* Single CLASS item in both loops: separating declaration from
+ 1139       IMPLEMENTATION at the loop level needs 2-token lookahead
+ 1140       (CLASS ident vs CLASS IMPLEMENTATION), which LL(1) cannot do.
+ 1141       The second token decides after CLASS is consumed. A misplaced
+ 1142       CLASS IMPLEMENTATION inside TYPE still parses (harmless: the
+ 1143       whole unit ends 230 until lowering). *)
+ 1144    ClassItem
+ 1145      = "CLASS" ( "IMPLEMENTATION" ClassImplRest | ClassRest ) .
+ 1146    ClassRest                             (. VAR cn, m2, pn: SymTab.Name;
+ 1147                                               ct: SymTab.TypeIndex; .)
+ 1148      = GetIdent<cn>                      (. IF NOT SymTab.Enter(cn,
+ 1149                                               SymTab.KindType) THEN
+ 1150                                               SemError(200) END;
+ 1151                                             ct := SymTab.NewClass();
+ 1152                                             SymTab.SetSymType(cn, ct);
+ 1153                                             SymTab.PushClassScope(ct);
+ 1154                                             astCls := AST.MakeNode(AST.NkClassDecl);
+ 1155                                             AST.SetChild(astCls, 0,
+ 1156                                               AST.MakeLeaf(AST.NkIdent, cn));
+ 1157                                             astClsP := AST.NoNode;
+ 1158                                             astClsPTail := AST.NoNode;
+ 1159                                             astClsF := AST.NoNode;
+ 1160                                             astClsFTail := AST.NoNode;
+ 1161                                             astClsM := AST.NoNode;
+ 1162                                             astClsMTail := AST.NoNode; .)
+ 1163        [ Parents<ct> ]
+ 1164        ";"
+ 1165        { ClassField<ct> ";" }
+ 1166        { MethodHeading<pn, SymTab.InvalidType> ";"
+ 1167                                          (. Lower.ScopeLeave;
+ 1168                                             SymTab.CloseProc;
+ 1169                                             QbeGen.AbortFunc; .) }
+ 1170        "END"
+ 1171        GetIdent<m2>                      (. IF NOT SymTab.Equal(cn, m2) THEN
+ 1172                                               SemError(202) END;
+ 1173                                             SymTab.LayoutClass(ct);
+ 1174                                             SymTab.PopScope;
+ 1175                                             AST.SetChild(astCls, 1, astClsP);
+ 1176                                             AST.SetChild(astCls, 2, astClsF);
+ 1177                                             AST.SetChild(astCls, 3, astClsM);
+ 1178                                             astDecl := astCls; .) .
+ 1179    Parents<ct: SymTab.TypeIndex>         (. VAR p: SymTab.Name; .)
+ 1180      = "(" Parent1<ct>
+ 1181        { "," GetIdent<p>                 (. SemError(230); .) }
+ 1182        ")" .
+ 1183    Parent1<ct: SymTab.TypeIndex>         (. VAR p: SymTab.Name;
+ 1184                                               pt: SymTab.TypeIndex; .)
+ 1185      = GetIdent<p>                       (. IF NOT SymTab.Lookup(p) THEN
+ 1186                                               SemError(201)
+ 1187                                             ELSE pt := SymTab.SymType(p);
+ 1188                                               IF SymTab.ClassOf(pt) #
+ 1189                                                  SymTab.ClClass THEN
+ 1190                                                 SemError(230)
+ 1191                                               ELSE SymTab.SetParent(ct, pt)
+ 1192                                               END
+ 1193                                             END;
  1194                                             AstAppend(AST.NkFieldDecl,
- 1195                                               astClsF, astClsFTail, astNode); .) ) .
- 1196    MethodHeading<VAR pn: SymTab.Name; ct: SymTab.TypeIndex>
- 1197                                          (. VAR wantVirt: BOOLEAN; .)
- 1198      =                                   (. wantVirt := FALSE; .)
- 1199        [ "VIRTUAL"                       (. wantVirt := TRUE; .) ]
- 1200        ProcHeading<pn, ct>               (. IF wantVirt THEN
- 1201                                               SymTab.MarkVirtual END;
- 1202                                             astMethod := AST.MakeNode(AST.NkProcDecl);
- 1203                                             AST.SetChild(astMethod, 0,
- 1204                                               AST.MakeLeaf(AST.NkIdent, pn));
- 1205                                             IF wantVirt THEN
- 1206                                               AST.SetOp(astMethod, 3)
- 1207                                             ELSE AST.SetOp(astMethod, 0)
- 1208                                             END;
+ 1195                                               astClsP, astClsPTail,
+ 1196                                               AST.MakeLeaf(AST.NkIdent, p)); .) .
+ 1197    ClassField<ct: SymTab.TypeIndex>      (. VAR n, rhs: SymTab.Name;
+ 1198                                               t: SymTab.TypeIndex;
+ 1199                                               astNode: AST.Node; .)
+ 1200      = GetIdent<n>
+ 1201        ( "=" GetIdent<rhs>               (. IF NOT SymTab.Enter(n,
+ 1202                                               SymTab.KindConst) THEN
+ 1203                                               SemError(200) END;
+ 1204                                             astNode := AST.MakeNode(AST.NkConstDecl);
+ 1205                                             AST.SetChild(astNode, 0,
+ 1206                                               AST.MakeLeaf(AST.NkIdent, n));
+ 1207                                             AST.SetChild(astNode, 1,
+ 1208                                               AST.MakeLeaf(AST.NkIdent, rhs));
  1209                                             AstAppend(AST.NkFieldDecl,
- 1210                                               astClsM, astClsMTail, astMethod); .) .
- 1211    ClassImplRest                         (. VAR cn, m2: SymTab.Name;
- 1212                                               ct: SymTab.TypeIndex; .)
- 1213      = GetIdent<cn>                      (. IF NOT SymTab.Lookup(cn) THEN
- 1214                                               SemError(201);
- 1215                                               ct := SymTab.InvalidType
- 1216                                             ELSE ct := SymTab.SymType(cn);
- 1217                                               IF SymTab.ClassOf(ct) #
- 1218                                                  SymTab.ClClass THEN
- 1219                                                 SemError(230);
- 1220                                                 ct := SymTab.InvalidType
- 1221                                               END
- 1222                                             END;
- 1223                                             astCls := AST.MakeNode(AST.NkClassDecl);
- 1224                                             AST.SetOp(astCls, 1);
- 1225                                             AST.SetChild(astCls, 0,
- 1226                                               AST.MakeLeaf(AST.NkIdent, cn));
- 1227                                             astClsM := AST.NoNode;
- 1228                                             astClsMTail := AST.NoNode;
- 1229                                             astStmt := AST.NoNode;
- 1230                                             IF ct #
- 1231                                                SymTab.InvalidType THEN
- 1232                                               IF NOT SymTab.PushClassMembers(
- 1233                                                      ct) THEN
- 1234                                                 SemError(230) END;
- 1235                                               SymTab.PushImplClass(ct)
- 1236                                             END; .)
- 1237        ";" { MethodImpl<ct> ";" }
- 1238                                          (. astStmt := AST.NoNode; .)
- 1239        [ "BEGIN"                         (. astStmt := AST.MakeNode(AST.NkBlock);
- 1240                                             .)
- 1241          [ StatSeq ] ]
- 1242        "END"
- 1243        GetIdent<m2>                      (. IF NOT SymTab.Equal(cn, m2) THEN
- 1244                                               SemError(202) END;
- 1245                                             SymTab.PopImplClass;
- 1246                                             SymTab.PopScope;
- 1247                                             AST.SetChild(astCls, 1, AST.NoNode);
- 1248                                             AST.SetChild(astCls, 2, astStmt);
- 1249                                             AST.SetChild(astCls, 3, astClsM);
- 1250                                             astDecl := astCls; .) .
- 1251    MethodImpl<ct: SymTab.TypeIndex>      (. VAR pn: SymTab.Name;
- 1252                                               thisQ: QbeGen.QVal;
- 1253                                               methRes: SymTab.TypeIndex; .)
- 1254      = MethodHeading<pn, ct> ";"
- 1255                                          (. IF (ct #
- 1256                                                SymTab.InvalidType)
- 1257   AND NOT SymTab.MethodExists(ct,
- 1258                                                    pn) THEN
- 1259                                               SemError(201) END; .)
- 1260        ( "FORWARD"                       (. AST.SetOp(astMethod, 1);
- 1261                                             SymTab.MarkFwd;
- 1262                                             QbeGen.AbortFunc;
- 1263                                             Lower.ScopeLeave;
- 1264                                             SymTab.CloseProc; .)
- 1265        |                                 (.
- 1266                                             (* bind the receiver: bare
- 1267                                                field names resolve
- 1268                                                against THIS *)
- 1269                                              QbeGen.CopyOp("@", thisQ);
- 1270                                             QbeGen.PushWith(thisQ); .)
- 1271          Block<pn>                       (. AST.SetChild(astMethod, 1, astStmt);
- 1272                                             AST.SetChild(astMethod, 2, astBlkDecls);
- 1273                                             QbeGen.PopWith;
- 1274                                             methRes := SymTab.CurRes();
- 1275                                             Lower.ScopeLeave;
- 1276                                             SymTab.CloseProc;
- 1277                                             QbeGen.EndFunc(methRes); .) ) .
- 1278    ConstBlock                            (. VAR astSeq, astTail: AST.Node; .)
- 1279      = "CONST"                           (. astSeq := AST.NoNode;
- 1280                                             astTail := AST.NoNode; .)
- 1281        { ConstDecl ";"                   (. AstAppend(AST.NkDeclSeq,
- 1282                                               astSeq, astTail, astDecl); .) }
- 1283                                          (. astDecl := astSeq; .) .
- 1284    ConstDecl                             (. VAR n: SymTab.Name;
- 1285                                               t: SymTab.TypeIndex;
- 1286                                               qv: QbeGen.QVal;
- 1287                                               cls: INTEGER;
- 1288                                               astNode: AST.Node; .)
- 1289      = GetIdent<n>                       (. IF NOT SymTab.Enter(n,
- 1290                                               SymTab.KindConst) THEN
- 1291                                               SemError(200) END; .)
- 1292        "="
- 1293        Expr<t, qv> (. astNode := AST.MakeNode(AST.NkConstDecl);
- 1294                                             AST.SetChild(astNode, 0,
- 1295                                               AST.MakeLeaf(AST.NkIdent, n));
- 1296                                             AST.SetChild(astNode, 1, astCur);
- 1297                                             AST.SetTy(astNode, t);
- 1298                                             astDecl := astNode;
- 1299                                             Lower.NoteVar(n, SymTab.KindConst, t);
- 1300                                             Lower.NoteConstVal(qv);
- 1301                                             SymTab.SetSymType(n, t);
- 1302                                             cls := SymTab.ClassOf(t);
- 1303                                             IF (cls = SymTab.ClArray)
- 1304                                                OR (cls = SymTab.ClRecord)
- 1305                                                OR (cls = SymTab.ClClass)
- 1306                                                OR (cls = SymTab.ClStr)
- 1307                                                OR (cls = SymTab.ClUStr) THEN
- 1308                                               (* an aggregate/string
- 1309                                                  constant: qv is its
- 1310                                                  descriptor address; no
- 1311                                                  scalar data *)
- 1312                                               SymTab.SetSymVal(n, qv)
- 1313                                             ELSIF NOT QbeGen.IsImm(qv) THEN
- 1314                                               SemError(230)
- 1315                                             ELSE
- 1316                                               SymTab.SetSymVal(n, qv);
- 1317                                             END; .) .
- 1318    VarBlock                              (. VAR astSeq, astTail: AST.Node; .)
- 1319      = "VAR"                             (. astSeq := AST.NoNode;
- 1320                                             astTail := AST.NoNode; .)
- 1321        { VarDecl ";"                     (. AstAppend(AST.NkDeclSeq,
- 1322                                               astSeq, astTail, astDecl); .) }
- 1323                                          (. astDecl := astSeq; .) .
- 1324    VarDecl                               (. VAR nm: SymTab.Name;
- 1325                                               t: SymTab.TypeIndex;
- 1326                                               i: CARDINAL;
- 1327                                               cls: INTEGER;
- 1328                                               astNode, astTail: AST.Node; .)
- 1329      = VarIdents ":"
- 1330        Type<t, FALSE> (. astNode := AST.MakeNode(AST.NkVarDecl);
- 1331                                             astTail := astNode;
- 1332                                             i := 0;
- 1333                                             WHILE i < SymTab.PendCount() DO
- 1334                                               SymTab.PendName(i, nm);
- 1335                                               Lower.NoteVar(nm, SymTab.KindVar, t);
- 1336                                               (* chunked: a VAR list can
- 1337                                                  exceed AST.MaxChild *)
- 1338                                               AstAppend(AST.NkBlock,
- 1339                                                 astNode, astTail,
- 1340                                                 AST.MakeLeaf(AST.NkIdent, nm));
- 1341                                               INC(i)
- 1342                                             END;
- 1343                                             AST.SetTy(astNode, t);
- 1344                                             astDecl := astNode;
- 1345                                             cls := SymTab.ClassOf(t);
- 1346                                             IF (t # SymTab.InvalidType)
- 1347   AND NOT SymTab.IsUnresolved(t)
- 1348   AND (cls # SymTab.ClInt)
- 1349   AND (cls # SymTab.ClBool)
- 1350   AND (cls # SymTab.ClChar)
- 1351   AND (cls # SymTab.ClReal)
- 1352   AND (cls # SymTab.ClArray)
- 1353   AND (cls # SymTab.ClSet)
- 1354   AND (cls # SymTab.ClRecord)
- 1355   AND (cls # SymTab.ClPtr)
- 1356   AND (cls # SymTab.ClLong)
- 1357   AND (cls # SymTab.ClProc)
- 1358   AND (cls # SymTab.ClUChar)
- 1359   AND (cls # SymTab.ClUStr)
- 1360   AND (cls # SymTab.ClEnum)
- 1361   AND (cls # SymTab.ClClass) THEN
- 1362                                               SemError(230) END;
- 1363                                             IF QbeGen.LocFull() THEN
- 1364                                               SemError(233) END;
- 1365                                             i := 0;
- 1366                                             IF SymTab.IsUnresolved(t)
- 1367                                                AND NOT SymTab.InProc() THEN
- 1368                                               (* a forward-typed global:
- 1369                                                  defer emission until the
- 1370                                                  TYPE block completes *)
- 1371                                               AST.SetOp(astNode, 1);
- 1372                                               WHILE i < SymTab.PendCount() DO
- 1373                                                 SymTab.PendName(i, nm);
- 1374                                                 IF nPendVar <=
- 1375                                                    HIGH(pendVarName) THEN
- 1376                                                   pendVarName[nPendVar] := nm;
- 1377                                                   pendVarT[nPendVar] := t;
- 1378                                                   INC(nPendVar)
- 1379                                                 END;
- 1380                                                 INC(i)
- 1381                                               END
- 1382                                             ELSE
- 1383                                               WHILE i < SymTab.PendCount() DO
- 1384                                                 SymTab.PendName(i, nm);
- 1385                                                 INC(i)
- 1386                                               END
- 1387                                             END;
- 1388                                             (* a plain VAR list, not a
- 1389                                                heading: the signature
- 1390                                                result is discarded *)
- 1391                                             IF NOT SymTab.FixPending(t) THEN
- 1392                                             END; .) .
- 1393    VarIdents                             (. VAR n: SymTab.Name; .)
- 1394      = GetIdent<n>                       (. IF NOT SymTab.EnterPending(n,
- 1395                                               SymTab.KindVar) THEN
- 1396                                               SemError(200) END; .)
- 1397        { ","
- 1398          GetIdent<n>                     (. IF NOT SymTab.EnterPending(n,
- 1399                                               SymTab.KindVar) THEN
- 1400                                               SemError(200) END; .) } .
- 1401    ParIdents<isV: BOOLEAN>               (. VAR n: SymTab.Name; .)
- 1402      = GetIdent<n>                       (. IF NOT SymTab.EnterParam(n, isV) THEN
- 1403                                               SemError(200) END; .)
- 1404        { "," GetIdent<n>                 (. IF NOT SymTab.EnterParam(n, isV) THEN
- 1405                                               SemError(200) END; .) } .
- 1406    (* Procedure headings enter scopes/params/result and buffer the
- 1407       QBE header; bodies lower to functions (4.1, module level only).
- 1408       FORWARD marks; the body heading re-enters (signature compare
- 1409       deferred). Nested procedures parse + check, lowering = 4.2. *)
- 1410    ProcHeading<VAR pn: SymTab.Name; methCls: SymTab.TypeIndex>
- 1411                                          (. VAR t: SymTab.TypeIndex;
- 1412                                               mg: QbeGen.QVal; .)
- 1413      = "PROCEDURE"
- 1414        GetIdent<pn>                      (. IF methCls #
- 1415                                                SymTab.InvalidType THEN
- 1416                                             (* a method: resume the
- 1417                                                declared symbol (reuse
- 1418                                                its uid) *)
- 1419                                             IF NOT SymTab.ResumeMethod(
- 1420                                                  methCls, pn) THEN
- 1421                                               SemError(200) END
- 1422                                             ELSIF NOT SymTab.EnterProc(pn) THEN
- 1423                                             IF NOT SymTab.ReenterProc(pn) THEN
- 1424                                               IF NOT SymTab.ResumeProc(pn) THEN
- 1425                                                 SemError(200) END
- 1426                                               END
- 1427                                             END;
- 1428                                             Lower.ScopeEnter;
- 1429                                             Lower.NoteProc(pn,
- 1430                                               SymTab.ProcUid(pn),
- 1431                                               SymTab.InvalidType,
- 1432                                               SymTab.ProcDepthOf(pn),
- 1433                                               FALSE);
- 1434                                             QbeGen.BeginFunc("");
- 1435                                             IF methCls #
- 1436                                                SymTab.InvalidType THEN
- 1437                                               (* hidden THIS receiver:
- 1438                                                  a VAR param of the
- 1439                                                  class type, pushed as
- 1440                                                  the WITH base *)
- 1441                                               IF NOT SymTab.EnterThisParam(
- 1442                                                    methCls) THEN
- 1443                                                 SemError(200) END;
- 1444                                               IF NOT QbeGen.FuncParam(
- 1445                                                    "THIS", TRUE,
- 1446                                                    methCls) THEN
- 1447                                                 SemError(233) END
- 1448                                             END; .)
- 1449        [ FormalParams ]
- 1450        [ ":" TypeIdent<t>                (. IF NOT SymTab.SetProcRes(t) THEN
- 1451                                               SemError(235) END;
- 1452                                             Lower.SetProcRes(t); .) ] .
- 1453    FormalParams
- 1454      = "(" [ ParamSection { ";" ParamSection } ] ")" .
- 1455    ParamSection                          (. VAR t: SymTab.TypeIndex;
- 1456                                               nm: SymTab.Name;
- 1457                                               i: CARDINAL;
- 1458                                               isV: BOOLEAN; .)
- 1459      =                                   (. isV := FALSE; .)
- 1460        [ "VAR"                           (. isV := TRUE; .) ]
- 1461        ParIdents<isV> ":" Type<t, TRUE>  (. i := 0;
- 1462                                             WHILE i < SymTab.PendCount() DO
- 1463                                               SymTab.PendName(i, nm);
- 1464                                               Lower.NoteParam(nm, t, isV);
- 1465                                               Lower.NoteVar(nm, SymTab.KindParam, t);
- 1466                                               (* value open arrays are
- 1467                                                  passed as descriptor
- 1468                                                  addresses (no copy):
- 1469                                                  same representation as
- 1470                                                  VAR formals *)
- 1471                                               IF NOT QbeGen.FuncParam(nm,
- 1472                                                    isV
- 1473                                                    OR SymTab.IsOpenArray(t),
- 1474                                                    t) THEN
- 1475                                                 SemError(233) END;
- 1476                                               INC(i)
- 1477                                             END;
- 1478                                             IF NOT SymTab.FixPending(t) THEN
- 1479                                               SemError(235) END; .) .
- 1480    (* Nested procedures lower like top-level ones (4.2): the
- 1481       static link gives them their parent's frame. Methods keep
- 1482       parse-now/230-later. *)
- 1483    ProcDecl                              (. VAR pn: SymTab.Name;
- 1484                                               astNode: AST.Node; .)
- 1485      = ProcHeading<pn, SymTab.InvalidType> ";"
- 1486                                          (. astNode := AST.MakeNode(AST.NkProcDecl);
- 1487                                             AST.SetOp(astNode, 0);
- 1488                                             AST.SetChild(astNode, 0,
- 1489                                               AST.MakeLeaf(AST.NkIdent, pn));
- 1490                                             Lower.NoteProcNode(astNode); .)
- 1491        ( "FORWARD"                       (. AST.SetOp(astNode, 1);
- 1492                                             astDecl := astNode;
- 1493                                             Lower.ScopeLeave;
- 1494                                             SymTab.MarkFwd;
- 1495                                             SymTab.CloseProc;
- 1496                                             QbeGen.AbortFunc; .)
- 1497        | "EXTERNAL"                      (. AST.SetOp(astNode, 2);
- 1498                                             astDecl := astNode;
- 1499                                             Lower.MarkProcExternal;
- 1500                                             Lower.ScopeLeave;
- 1501                                             SymTab.MarkExternal("");
- 1502                                             SymTab.CloseProc;
- 1503                                             QbeGen.AbortFunc; .)
- 1504        |                                 
- 1505          Block<pn>                       (. AST.SetChild(astNode, 1, astStmt);
- 1506                                             AST.SetChild(astNode, 2, astBlkDecls);
- 1507                                             astDecl := astNode;
- 1508                                             Lower.ScopeLeave;
- 1509                                             SymTab.CloseProc;
- 1510                                             QbeGen.EndFunc(
- 1511                                               SymTab.ProcRes(pn)); .) ) .
- 1512    Block<pn: SymTab.Name>                (. VAR m2: SymTab.Name; .)
- 1513      =                                   (. IF twoPhaseParse AND (procNest = 0) THEN
- 1514                                              ProbeBody(pn) END;
- 1515                                            INC(procNest); .)
- 1516        DeclSeq                           (. astBlkDecls := astDecl;
- 1517                                             astStmt := AST.NoNode;
- 1518                                             nLab := 0; nGot := 0; .)
- 1519        [ "BEGIN"                         (. (* an empty body is still a
- 1520                                               body: mark it so Lower
- 1521                                               does not read it as a
- 1522                                               definition heading *)
- 1523                                             IF astStmt = AST.NoNode THEN
- 1524                                               astStmt :=
- 1525                                                 AST.MakeNode(AST.NkBlock)
- 1526                                             END; .)
- 1527          [ StatSeq ] ]
- 1528        "END"
- 1529        GetIdent<m2>                      (. IF NOT SymTab.Equal(pn, m2) THEN
- 1530                                               SemError(202) END;
- 1531                                             DEC(procNest);
- 1532                                             CheckGotos; .) .
- 1533    StatSeq                               (. VAR astSeq, astTail: AST.Node; .)
- 1534      =                                   (. astSeq := AST.NoNode;
- 1535                                             astTail := AST.NoNode; .)
- 1536        Statement                         (. AstAppend(AST.NkBlock,
- 1537                                               astSeq, astTail, astStmt); .)
- 1538        { ";" [ Statement                 (. AstAppend(AST.NkBlock,
- 1539                                               astSeq, astTail, astStmt); .) ] }
- 1540                                          (. astStmt := astSeq; .) .
- 1541    (* Trailing/empty statements (`a; ; b`, Coco/R's generated `;;`)
- 1542       are accepted: the statement after ';' is optional. *)
- 1543    Statement                             (. VAR lx: QbeGen.QVal; lxnm: SymTab.Name; .)
- 1544      = (. astStmt := AST.NoNode; .)
- 1545        ( AssOrCall
- 1546      | IfStat
- 1547      | WhileStat
- 1548      | RepeatStat
- 1549      | LoopStat
- 1550      | ForStat
- 1551      | CaseStat
- 1552      | WithStat
- 1553      | ReturnStat
- 1554      | HaltStat
- 1555      | NewStat
- 1556      | DisposeStat
- 1557      | IncDecStat
- 1558      | InclExclStat
- 1559      | "EXIT"                            (. IF NOT QbeGen.TopLoop(lx) THEN
- 1560                                               SemError(230) END;
- 1561                                             astStmt := AST.MakeNode(AST.NkExit); .)
- 1562      | "GOTO" GetIdent<lxnm>             (. NoteGoto(lxnm);
- 1563                                             astStmt := AST.MakeNode(AST.NkGoto);
- 1564                                             AST.SetChild(astStmt, 0,
- 1565                                               AST.MakeLeaf(AST.NkIdent, lxnm)); .) ) .
- 1566    (* INCL(set, elem) / EXCL(set, elem): PIM set-element builtins. *)
- 1567    InclExclStat                          (. VAR at, et2: SymTab.TypeIndex;
- 1568                                               dk: INTEGER;
- 1569                                               qd, qe: QbeGen.QVal;
- 1570                                               qn: SymTab.Name;
- 1571                                               sfx, isInc: BOOLEAN;
- 1572                                               astNode, astD: AST.Node; .)
- 1573      = ( "INCL"                          (. isInc := TRUE; .)
- 1574        | "EXCL"                          (. isInc := FALSE; .) )
- 1575        "(" Design<at, dk, qd, qn, sfx> (. astD := astCur; .) ","
- 1576        Expr<et2, qe> ")"
- 1577                                          (. astNode := AST.MakeNode(AST.NkCall);
- 1578                                             IF isInc THEN
- 1579                                               AST.SetChild(astNode, 0,
- 1580                                                 AST.MakeLeaf(AST.NkIdent, "INCL"))
- 1581                                             ELSE AST.SetChild(astNode, 0,
- 1582                                                 AST.MakeLeaf(AST.NkIdent, "EXCL"))
- 1583                                             END;
- 1584                                             IF astD # AST.NoNode THEN
- 1585                                               AST.SetChild(astNode, 1, astD) END;
- 1586                                             IF astCur # AST.NoNode THEN
- 1587                                               AST.SetChild(astNode, 2, astCur) END;
- 1588                                             astStmt := astNode; .)
- 1589                                          (. IF (at # SymTab.InvalidType)
- 1590    AND (SymTab.ClassOf(at) # SymTab.ClSet) THEN
- 1591                                               SemError(222)
- 1592                                             END; .) .
- 1593    (* INC(v [,step]) / DEC(v [,step]) as builtin statements over an
- 1594       integer designator. *)
- 1595    IncDecStat                            (. VAR dt, et2: SymTab.TypeIndex;
- 1596                                               dk: INTEGER;
- 1597                                               qd, qv, qn2, qstep:
- 1598                                                 QbeGen.QVal;
- 1599                                               qn: SymTab.Name;
- 1600                                               sfx, isInc: BOOLEAN;
- 1601                                               astNode, astD, astStep:
- 1602                                                 AST.Node; .)
- 1603      =                                   (. isInc := TRUE; .)
- 1604        ( "INC"                           (. isInc := TRUE; .)
- 1605        | "DEC"                           (. isInc := FALSE; .) )
- 1606        "("                               (. astStep := AST.NoNode; .)
- 1607        Design<dt, dk, qd, qn, sfx> (. astD := astCur; .)
- 1608        [ "," Expr<et2, qstep> (. astStep := astCur; .) ]
- 1609        ")"                               (. astNode := AST.MakeNode(AST.NkCall);
- 1610                                             IF isInc THEN
- 1611                                               AST.SetChild(astNode, 0,
- 1612                                                 AST.MakeLeaf(AST.NkIdent, "INC"))
- 1613                                             ELSE AST.SetChild(astNode, 0,
- 1614                                                 AST.MakeLeaf(AST.NkIdent, "DEC"))
- 1615                                             END;
- 1616                                             IF astD # AST.NoNode THEN
- 1617                                               AST.SetChild(astNode, 1, astD) END;
- 1618                                             IF astStep # AST.NoNode THEN
- 1619                                               AST.SetChild(astNode, 2, astStep) END;
- 1620                                             astStmt := astNode; .)                               (. IF dt = SymTab.InvalidType THEN
- 1621                                             ELSIF (dk # SymTab.KindVar)
- 1622   AND (dk # SymTab.KindParam)
- 1623   AND (dk # SymTab.KindField) THEN
- 1624                                               SemError(210)
- 1625                                             ELSIF NOT SymTab.IsIntFamily(dt) THEN
- 1626                                               SemError(211)
+ 1210                                               astClsF, astClsFTail, astNode);
+ 1211                                             IF SymTab.Lookup(rhs) THEN
+ 1212                                               SymTab.SetSymType(n,
+ 1213                                                 SymTab.SymType(rhs))
+ 1214                                             END; .)
+ 1215        |                                 (. IF NOT SymTab.FieldPending(ct,
+ 1216                                               n) THEN
+ 1217                                               SemError(200) END;
+ 1218                                             astNode := AST.MakeNode(AST.NkVarDecl);
+ 1219                                             AST.SetChild(astNode, 0,
+ 1220                                               AST.MakeLeaf(AST.NkIdent, n)); .)
+ 1221          { "," GetIdent<n>               (. IF NOT SymTab.FieldPending(ct,
+ 1222                                               n) THEN
+ 1223                                               SemError(200) END;
+ 1224                                             AST.SetChild(astNode,
+ 1225                                               AST.NChild(astNode),
+ 1226                                               AST.MakeLeaf(AST.NkIdent, n)); .) }
+ 1227          ":" Type<t, FALSE>              (. SymTab.FixPendingF(ct, t);
+ 1228                                             AST.SetTy(astNode, t);
+ 1229                                             AstAppend(AST.NkFieldDecl,
+ 1230                                               astClsF, astClsFTail, astNode); .) ) .
+ 1231    MethodHeading<VAR pn: SymTab.Name; ct: SymTab.TypeIndex>
+ 1232                                          (. VAR wantVirt: BOOLEAN; .)
+ 1233      =                                   (. wantVirt := FALSE; .)
+ 1234        [ "VIRTUAL"                       (. wantVirt := TRUE; .) ]
+ 1235        ProcHeading<pn, ct>               (. IF wantVirt THEN
+ 1236                                               SymTab.MarkVirtual END;
+ 1237                                             astMethod := AST.MakeNode(AST.NkProcDecl);
+ 1238                                             AST.SetChild(astMethod, 0,
+ 1239                                               AST.MakeLeaf(AST.NkIdent, pn));
+ 1240                                             IF wantVirt THEN
+ 1241                                               AST.SetOp(astMethod, 3)
+ 1242                                             ELSE AST.SetOp(astMethod, 0)
+ 1243                                             END;
+ 1244                                             AstAppend(AST.NkFieldDecl,
+ 1245                                               astClsM, astClsMTail, astMethod); .) .
+ 1246    ClassImplRest                         (. VAR cn, m2: SymTab.Name;
+ 1247                                               ct: SymTab.TypeIndex; .)
+ 1248      = GetIdent<cn>                      (. IF NOT SymTab.Lookup(cn) THEN
+ 1249                                               SemError(201);
+ 1250                                               ct := SymTab.InvalidType
+ 1251                                             ELSE ct := SymTab.SymType(cn);
+ 1252                                               IF SymTab.ClassOf(ct) #
+ 1253                                                  SymTab.ClClass THEN
+ 1254                                                 SemError(230);
+ 1255                                                 ct := SymTab.InvalidType
+ 1256                                               END
+ 1257                                             END;
+ 1258                                             astCls := AST.MakeNode(AST.NkClassDecl);
+ 1259                                             AST.SetOp(astCls, 1);
+ 1260                                             AST.SetChild(astCls, 0,
+ 1261                                               AST.MakeLeaf(AST.NkIdent, cn));
+ 1262                                             astClsM := AST.NoNode;
+ 1263                                             astClsMTail := AST.NoNode;
+ 1264                                             astStmt := AST.NoNode;
+ 1265                                             IF ct #
+ 1266                                                SymTab.InvalidType THEN
+ 1267                                               IF NOT SymTab.PushClassMembers(
+ 1268                                                      ct) THEN
+ 1269                                                 SemError(230) END;
+ 1270                                               SymTab.PushImplClass(ct)
+ 1271                                             END; .)
+ 1272        ";" { MethodImpl<ct> ";" }
+ 1273                                          (. astStmt := AST.NoNode; .)
+ 1274        [ "BEGIN"                         (. astStmt := AST.MakeNode(AST.NkBlock);
+ 1275                                             .)
+ 1276          [ StatSeq ] ]
+ 1277        "END"
+ 1278        GetIdent<m2>                      (. IF NOT SymTab.Equal(cn, m2) THEN
+ 1279                                               SemError(202) END;
+ 1280                                             SymTab.PopImplClass;
+ 1281                                             SymTab.PopScope;
+ 1282                                             AST.SetChild(astCls, 1, AST.NoNode);
+ 1283                                             AST.SetChild(astCls, 2, astStmt);
+ 1284                                             AST.SetChild(astCls, 3, astClsM);
+ 1285                                             astDecl := astCls; .) .
+ 1286    MethodImpl<ct: SymTab.TypeIndex>      (. VAR pn: SymTab.Name;
+ 1287                                               thisQ: QbeGen.QVal;
+ 1288                                               methRes: SymTab.TypeIndex; .)
+ 1289      = MethodHeading<pn, ct> ";"
+ 1290                                          (. IF (ct #
+ 1291                                                SymTab.InvalidType)
+ 1292   AND NOT SymTab.MethodExists(ct,
+ 1293                                                    pn) THEN
+ 1294                                               SemError(201) END; .)
+ 1295        ( "FORWARD"                       (. AST.SetOp(astMethod, 1);
+ 1296                                             SymTab.MarkFwd;
+ 1297                                             QbeGen.AbortFunc;
+ 1298                                             Lower.ScopeLeave;
+ 1299                                             SymTab.CloseProc; .)
+ 1300        |                                 (.
+ 1301                                             (* bind the receiver: bare
+ 1302                                                field names resolve
+ 1303                                                against THIS *)
+ 1304                                              QbeGen.CopyOp("@", thisQ);
+ 1305                                             QbeGen.PushWith(thisQ); .)
+ 1306          Block<pn>                       (. AST.SetChild(astMethod, 1, astStmt);
+ 1307                                             AST.SetChild(astMethod, 2, astBlkDecls);
+ 1308                                             QbeGen.PopWith;
+ 1309                                             methRes := SymTab.CurRes();
+ 1310                                             Lower.ScopeLeave;
+ 1311                                             SymTab.CloseProc;
+ 1312                                             QbeGen.EndFunc(methRes); .) ) .
+ 1313    ConstBlock                            (. VAR astSeq, astTail: AST.Node; .)
+ 1314      = "CONST"                           (. astSeq := AST.NoNode;
+ 1315                                             astTail := AST.NoNode; .)
+ 1316        { ConstDecl ";"                   (. AstAppend(AST.NkDeclSeq,
+ 1317                                               astSeq, astTail, astDecl); .) }
+ 1318                                          (. astDecl := astSeq; .) .
+ 1319    ConstDecl                             (. VAR n: SymTab.Name;
+ 1320                                               t: SymTab.TypeIndex;
+ 1321                                               qv: QbeGen.QVal;
+ 1322                                               cls: INTEGER;
+ 1323                                               astNode: AST.Node; .)
+ 1324      = GetIdent<n>                       (. IF NOT SymTab.Enter(n,
+ 1325                                               SymTab.KindConst) THEN
+ 1326                                               SemError(200) END; .)
+ 1327        "="
+ 1328        Expr<t, qv> (. astNode := AST.MakeNode(AST.NkConstDecl);
+ 1329                                             AST.SetChild(astNode, 0,
+ 1330                                               AST.MakeLeaf(AST.NkIdent, n));
+ 1331                                             AST.SetChild(astNode, 1, astCur);
+ 1332                                             AST.SetTy(astNode, t);
+ 1333                                             astDecl := astNode;
+ 1334                                             Lower.NoteVar(n, SymTab.KindConst, t);
+ 1335                                             Lower.NoteConstVal(qv);
+ 1336                                             SymTab.SetSymType(n, t);
+ 1337                                             cls := SymTab.ClassOf(t);
+ 1338                                             IF (cls = SymTab.ClArray)
+ 1339                                                OR (cls = SymTab.ClRecord)
+ 1340                                                OR (cls = SymTab.ClClass)
+ 1341                                                OR (cls = SymTab.ClStr)
+ 1342                                                OR (cls = SymTab.ClUStr) THEN
+ 1343                                               (* an aggregate/string
+ 1344                                                  constant: qv is its
+ 1345                                                  descriptor address; no
+ 1346                                                  scalar data *)
+ 1347                                               SymTab.SetSymVal(n, qv)
+ 1348                                             ELSIF NOT QbeGen.IsImm(qv) THEN
+ 1349                                               SemError(230)
+ 1350                                             ELSE
+ 1351                                               SymTab.SetSymVal(n, qv);
+ 1352                                             END; .) .
+ 1353    VarBlock                              (. VAR astSeq, astTail: AST.Node; .)
+ 1354      = "VAR"                             (. astSeq := AST.NoNode;
+ 1355                                             astTail := AST.NoNode; .)
+ 1356        { VarDecl ";"                     (. AstAppend(AST.NkDeclSeq,
+ 1357                                               astSeq, astTail, astDecl); .) }
+ 1358                                          (. astDecl := astSeq; .) .
+ 1359    VarDecl                               (. VAR nm: SymTab.Name;
+ 1360                                               t: SymTab.TypeIndex;
+ 1361                                               i: CARDINAL;
+ 1362                                               cls: INTEGER;
+ 1363                                               astNode, astTail: AST.Node; .)
+ 1364      = VarIdents ":"
+ 1365        Type<t, FALSE> (. astNode := AST.MakeNode(AST.NkVarDecl);
+ 1366                                             astTail := astNode;
+ 1367                                             i := 0;
+ 1368                                             WHILE i < SymTab.PendCount() DO
+ 1369                                               SymTab.PendName(i, nm);
+ 1370                                               Lower.NoteVar(nm, SymTab.KindVar, t);
+ 1371                                               (* chunked: a VAR list can
+ 1372                                                  exceed AST.MaxChild *)
+ 1373                                               AstAppend(AST.NkBlock,
+ 1374                                                 astNode, astTail,
+ 1375                                                 AST.MakeLeaf(AST.NkIdent, nm));
+ 1376                                               INC(i)
+ 1377                                             END;
+ 1378                                             AST.SetTy(astNode, t);
+ 1379                                             astDecl := astNode;
+ 1380                                             cls := SymTab.ClassOf(t);
+ 1381                                             IF (t # SymTab.InvalidType)
+ 1382   AND NOT SymTab.IsUnresolved(t)
+ 1383   AND (cls # SymTab.ClInt)
+ 1384   AND (cls # SymTab.ClBool)
+ 1385   AND (cls # SymTab.ClChar)
+ 1386   AND (cls # SymTab.ClReal)
+ 1387   AND (cls # SymTab.ClArray)
+ 1388   AND (cls # SymTab.ClSet)
+ 1389   AND (cls # SymTab.ClRecord)
+ 1390   AND (cls # SymTab.ClPtr)
+ 1391   AND (cls # SymTab.ClLong)
+ 1392   AND (cls # SymTab.ClProc)
+ 1393   AND (cls # SymTab.ClUChar)
+ 1394   AND (cls # SymTab.ClUStr)
+ 1395   AND (cls # SymTab.ClEnum)
+ 1396   AND (cls # SymTab.ClClass) THEN
+ 1397                                               SemError(230) END;
+ 1398                                             IF QbeGen.LocFull() THEN
+ 1399                                               SemError(233) END;
+ 1400                                             i := 0;
+ 1401                                             IF SymTab.IsUnresolved(t)
+ 1402                                                AND NOT SymTab.InProc() THEN
+ 1403                                               (* a forward-typed global:
+ 1404                                                  defer emission until the
+ 1405                                                  TYPE block completes *)
+ 1406                                               AST.SetOp(astNode, 1);
+ 1407                                               WHILE i < SymTab.PendCount() DO
+ 1408                                                 SymTab.PendName(i, nm);
+ 1409                                                 IF nPendVar <=
+ 1410                                                    HIGH(pendVarName) THEN
+ 1411                                                   pendVarName[nPendVar] := nm;
+ 1412                                                   pendVarT[nPendVar] := t;
+ 1413                                                   INC(nPendVar)
+ 1414                                                 END;
+ 1415                                                 INC(i)
+ 1416                                               END
+ 1417                                             ELSE
+ 1418                                               WHILE i < SymTab.PendCount() DO
+ 1419                                                 SymTab.PendName(i, nm);
+ 1420                                                 INC(i)
+ 1421                                               END
+ 1422                                             END;
+ 1423                                             (* a plain VAR list, not a
+ 1424                                                heading: the signature
+ 1425                                                result is discarded *)
+ 1426                                             IF NOT SymTab.FixPending(t) THEN
+ 1427                                             END; .) .
+ 1428    VarIdents                             (. VAR n: SymTab.Name; .)
+ 1429      = GetIdent<n>                       (. IF NOT SymTab.EnterPending(n,
+ 1430                                               SymTab.KindVar) THEN
+ 1431                                               SemError(200) END; .)
+ 1432        { ","
+ 1433          GetIdent<n>                     (. IF NOT SymTab.EnterPending(n,
+ 1434                                               SymTab.KindVar) THEN
+ 1435                                               SemError(200) END; .) } .
+ 1436    ParIdents<isV: BOOLEAN>               (. VAR n: SymTab.Name; .)
+ 1437      = GetIdent<n>                       (. IF NOT SymTab.EnterParam(n, isV) THEN
+ 1438                                               SemError(200) END; .)
+ 1439        { "," GetIdent<n>                 (. IF NOT SymTab.EnterParam(n, isV) THEN
+ 1440                                               SemError(200) END; .) } .
+ 1441    (* Procedure headings enter scopes/params/result and buffer the
+ 1442       QBE header; bodies lower to functions (4.1, module level only).
+ 1443       FORWARD marks; the body heading re-enters (signature compare
+ 1444       deferred). Nested procedures parse + check, lowering = 4.2. *)
+ 1445    ProcHeading<VAR pn: SymTab.Name; methCls: SymTab.TypeIndex>
+ 1446                                          (. VAR t: SymTab.TypeIndex;
+ 1447                                               mg: QbeGen.QVal; .)
+ 1448      = "PROCEDURE"
+ 1449        GetIdent<pn>                      (. IF methCls #
+ 1450                                                SymTab.InvalidType THEN
+ 1451                                             (* a method: resume the
+ 1452                                                declared symbol (reuse
+ 1453                                                its uid) *)
+ 1454                                             IF NOT SymTab.ResumeMethod(
+ 1455                                                  methCls, pn) THEN
+ 1456                                               SemError(200) END
+ 1457                                             ELSIF NOT SymTab.EnterProc(pn) THEN
+ 1458                                             IF NOT SymTab.ReenterProc(pn) THEN
+ 1459                                               IF NOT SymTab.ResumeProc(pn) THEN
+ 1460                                                 SemError(200) END
+ 1461                                               END
+ 1462                                             END;
+ 1463                                             Lower.ScopeEnter;
+ 1464                                             Lower.NoteProc(pn,
+ 1465                                               SymTab.ProcUid(pn),
+ 1466                                               SymTab.InvalidType,
+ 1467                                               SymTab.ProcDepthOf(pn),
+ 1468                                               FALSE);
+ 1469                                             QbeGen.BeginFunc("");
+ 1470                                             IF methCls #
+ 1471                                                SymTab.InvalidType THEN
+ 1472                                               (* hidden THIS receiver:
+ 1473                                                  a VAR param of the
+ 1474                                                  class type, pushed as
+ 1475                                                  the WITH base *)
+ 1476                                               IF NOT SymTab.EnterThisParam(
+ 1477                                                    methCls) THEN
+ 1478                                                 SemError(200) END;
+ 1479                                               IF NOT QbeGen.FuncParam(
+ 1480                                                    "THIS", TRUE,
+ 1481                                                    methCls) THEN
+ 1482                                                 SemError(233) END
+ 1483                                             END; .)
+ 1484        [ FormalParams ]
+ 1485        [ ":" TypeIdent<t>                (. IF NOT SymTab.SetProcRes(t) THEN
+ 1486                                               SemError(235) END;
+ 1487                                             Lower.SetProcRes(t); .) ] .
+ 1488    FormalParams
+ 1489      = "(" [ ParamSection { ";" ParamSection } ] ")" .
+ 1490    ParamSection                          (. VAR t: SymTab.TypeIndex;
+ 1491                                               nm: SymTab.Name;
+ 1492                                               i: CARDINAL;
+ 1493                                               isV: BOOLEAN; .)
+ 1494      =                                   (. isV := FALSE; .)
+ 1495        [ "VAR"                           (. isV := TRUE; .) ]
+ 1496        ParIdents<isV> ":" Type<t, TRUE>  (. i := 0;
+ 1497                                             WHILE i < SymTab.PendCount() DO
+ 1498                                               SymTab.PendName(i, nm);
+ 1499                                               Lower.NoteParam(nm, t, isV);
+ 1500                                               Lower.NoteVar(nm, SymTab.KindParam, t);
+ 1501                                               (* value open arrays are
+ 1502                                                  passed as descriptor
+ 1503                                                  addresses (no copy):
+ 1504                                                  same representation as
+ 1505                                                  VAR formals *)
+ 1506                                               IF NOT QbeGen.FuncParam(nm,
+ 1507                                                    isV
+ 1508                                                    OR SymTab.IsOpenArray(t),
+ 1509                                                    t) THEN
+ 1510                                                 SemError(233) END;
+ 1511                                               INC(i)
+ 1512                                             END;
+ 1513                                             IF NOT SymTab.FixPending(t) THEN
+ 1514                                               SemError(235) END; .) .
+ 1515    (* Nested procedures lower like top-level ones (4.2): the
+ 1516       static link gives them their parent's frame. Methods keep
+ 1517       parse-now/230-later. *)
+ 1518    ProcDecl                              (. VAR pn: SymTab.Name;
+ 1519                                               astNode: AST.Node; .)
+ 1520      = ProcHeading<pn, SymTab.InvalidType> ";"
+ 1521                                          (. astNode := AST.MakeNode(AST.NkProcDecl);
+ 1522                                             AST.SetOp(astNode, 0);
+ 1523                                             AST.SetChild(astNode, 0,
+ 1524                                               AST.MakeLeaf(AST.NkIdent, pn));
+ 1525                                             Lower.NoteProcNode(astNode); .)
+ 1526        ( "FORWARD"                       (. AST.SetOp(astNode, 1);
+ 1527                                             astDecl := astNode;
+ 1528                                             Lower.ScopeLeave;
+ 1529                                             SymTab.MarkFwd;
+ 1530                                             SymTab.CloseProc;
+ 1531                                             QbeGen.AbortFunc; .)
+ 1532        | "EXTERNAL"                      (. AST.SetOp(astNode, 2);
+ 1533                                             astDecl := astNode;
+ 1534                                             Lower.MarkProcExternal;
+ 1535                                             Lower.ScopeLeave;
+ 1536                                             SymTab.MarkExternal("");
+ 1537                                             SymTab.CloseProc;
+ 1538                                             QbeGen.AbortFunc; .)
+ 1539        |                                 
+ 1540          Block<pn>                       (. AST.SetChild(astNode, 1, astStmt);
+ 1541                                             AST.SetChild(astNode, 2, astBlkDecls);
+ 1542                                             astDecl := astNode;
+ 1543                                             Lower.ScopeLeave;
+ 1544                                             SymTab.CloseProc;
+ 1545                                             QbeGen.EndFunc(
+ 1546                                               SymTab.ProcRes(pn)); .) ) .
+ 1547    Block<pn: SymTab.Name>                (. VAR m2: SymTab.Name; .)
+ 1548      =                                   (. IF twoPhaseParse AND (procNest = 0) THEN
+ 1549                                              ProbeBody(pn) END;
+ 1550                                            INC(procNest); .)
+ 1551        DeclSeq                           (. astBlkDecls := astDecl;
+ 1552                                             astStmt := AST.NoNode;
+ 1553                                             nLab := 0; nGot := 0; .)
+ 1554        [ "BEGIN"                         (. (* an empty body is still a
+ 1555                                               body: mark it so Lower
+ 1556                                               does not read it as a
+ 1557                                               definition heading *)
+ 1558                                             IF astStmt = AST.NoNode THEN
+ 1559                                               astStmt :=
+ 1560                                                 AST.MakeNode(AST.NkBlock)
+ 1561                                             END; .)
+ 1562          [ StatSeq ] ]
+ 1563        "END"
+ 1564        GetIdent<m2>                      (. IF NOT SymTab.Equal(pn, m2) THEN
+ 1565                                               SemError(202) END;
+ 1566                                             DEC(procNest);
+ 1567                                             CheckGotos; .) .
+ 1568    StatSeq                               (. VAR astSeq, astTail: AST.Node; .)
+ 1569      =                                   (. astSeq := AST.NoNode;
+ 1570                                             astTail := AST.NoNode; .)
+ 1571        Statement                         (. AstAppend(AST.NkBlock,
+ 1572                                               astSeq, astTail, astStmt); .)
+ 1573        { ";" [ Statement                 (. AstAppend(AST.NkBlock,
+ 1574                                               astSeq, astTail, astStmt); .) ] }
+ 1575                                          (. astStmt := astSeq; .) .
+ 1576    (* Trailing/empty statements (`a; ; b`, Coco/R's generated `;;`)
+ 1577       are accepted: the statement after ';' is optional. *)
+ 1578    Statement                             (. VAR lx: QbeGen.QVal; lxnm: SymTab.Name; .)
+ 1579      = (. astStmt := AST.NoNode; .)
+ 1580        ( AssOrCall
+ 1581      | IfStat
+ 1582      | WhileStat
+ 1583      | RepeatStat
+ 1584      | LoopStat
+ 1585      | ForStat
+ 1586      | CaseStat
+ 1587      | WithStat
+ 1588      | ReturnStat
+ 1589      | HaltStat
+ 1590      | NewStat
+ 1591      | DisposeStat
+ 1592      | IncDecStat
+ 1593      | InclExclStat
+ 1594      | "EXIT"                            (. IF NOT QbeGen.TopLoop(lx) THEN
+ 1595                                               SemError(230) END;
+ 1596                                             astStmt := AST.MakeNode(AST.NkExit); .)
+ 1597      | "GOTO" GetIdent<lxnm>             (. NoteGoto(lxnm);
+ 1598                                             astStmt := AST.MakeNode(AST.NkGoto);
+ 1599                                             AST.SetChild(astStmt, 0,
+ 1600                                               AST.MakeLeaf(AST.NkIdent, lxnm)); .) ) .
+ 1601    (* INCL(set, elem) / EXCL(set, elem): PIM set-element builtins. *)
+ 1602    InclExclStat                          (. VAR at, et2: SymTab.TypeIndex;
+ 1603                                               dk: INTEGER;
+ 1604                                               qd, qe: QbeGen.QVal;
+ 1605                                               qn: SymTab.Name;
+ 1606                                               sfx, isInc: BOOLEAN;
+ 1607                                               astNode, astD: AST.Node; .)
+ 1608      = ( "INCL"                          (. isInc := TRUE; .)
+ 1609        | "EXCL"                          (. isInc := FALSE; .) )
+ 1610        "(" Design<at, dk, qd, qn, sfx> (. astD := astCur; .) ","
+ 1611        Expr<et2, qe> ")"
+ 1612                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 1613                                             IF isInc THEN
+ 1614                                               AST.SetChild(astNode, 0,
+ 1615                                                 AST.MakeLeaf(AST.NkIdent, "INCL"))
+ 1616                                             ELSE AST.SetChild(astNode, 0,
+ 1617                                                 AST.MakeLeaf(AST.NkIdent, "EXCL"))
+ 1618                                             END;
+ 1619                                             IF astD # AST.NoNode THEN
+ 1620                                               AST.SetChild(astNode, 1, astD) END;
+ 1621                                             IF astCur # AST.NoNode THEN
+ 1622                                               AST.SetChild(astNode, 2, astCur) END;
+ 1623                                             astStmt := astNode; .)
+ 1624                                          (. IF (at # SymTab.InvalidType)
+ 1625    AND (SymTab.ClassOf(at) # SymTab.ClSet) THEN
+ 1626                                               SemError(222)
  1627                                             END; .) .
- 1628    (* NEW/DISPOSE as builtin statements (no call syntax until step 4).
- 1629       Targets are pointer designators; DISPOSE nils afterwards (safer
- 1630       than Wirth-undefined; documented). DISPOSE is shallow. *)
- 1631    NewStat                               (. VAR dt: SymTab.TypeIndex;
- 1632                                               dk: INTEGER;
- 1633                                               qd, qm: QbeGen.QVal;
+ 1628    (* INC(v [,step]) / DEC(v [,step]) as builtin statements over an
+ 1629       integer designator. *)
+ 1630    IncDecStat                            (. VAR dt, et2: SymTab.TypeIndex;
+ 1631                                               dk: INTEGER;
+ 1632                                               qd, qv, qn2, qstep:
+ 1633                                                 QbeGen.QVal;
  1634                                               qn: SymTab.Name;
- 1635                                               sfx: BOOLEAN;
- 1636                                               bt: SymTab.TypeIndex;
- 1637                                               astNode, astD: AST.Node; .)
- 1638      = "NEW" "(" Design<dt, dk, qd, qn, sfx> (. astD := astCur; .) ")"
- 1639                                          (. astNode := AST.MakeNode(AST.NkCall);
- 1640                                             AST.SetChild(astNode, 0,
- 1641                                               AST.MakeLeaf(AST.NkIdent, "NEW"));
- 1642                                             IF astD # AST.NoNode THEN
- 1643                                               AST.SetChild(astNode, 1, astD) END;
- 1644                                             astStmt := astNode; .)
- 1645                                           (. IF dt = SymTab.InvalidType THEN
- 1646                                              ELSIF (dk # SymTab.KindVar)
- 1647    AND (dk # SymTab.KindParam)
- 1648    AND (dk # SymTab.KindField) THEN
- 1649                                                SemError(210)
- 1650                                              ELSIF SymTab.ClassOf(dt) #
- 1651                                                    SymTab.ClPtr THEN
- 1652                                                SemError(219)
- 1653                                              END; .) .
- 1654    DisposeStat                           (. VAR dt: SymTab.TypeIndex;
- 1655                                               dk: INTEGER;
- 1656                                               qd, qv: QbeGen.QVal;
- 1657                                               qn: SymTab.Name;
- 1658                                               sfx: BOOLEAN;
- 1659                                               astNode, astD: AST.Node; .)
- 1660      = "DISPOSE" "(" Design<dt, dk, qd, qn, sfx> (. astD := astCur; .) ")"
- 1661                                          (. astNode := AST.MakeNode(AST.NkCall);
- 1662                                             AST.SetChild(astNode, 0,
- 1663                                               AST.MakeLeaf(AST.NkIdent, "DISPOSE"));
- 1664                                             IF astD # AST.NoNode THEN
- 1665                                               AST.SetChild(astNode, 1, astD) END;
- 1666                                             astStmt := astNode; .)
- 1667                                           (. IF dt = SymTab.InvalidType THEN
- 1668                                              ELSIF (dk # SymTab.KindVar)
- 1669    AND (dk # SymTab.KindParam)
- 1670    AND (dk # SymTab.KindField) THEN
- 1671                                                SemError(210)
- 1672                                              ELSIF SymTab.ClassOf(dt) #
- 1673                                                    SymTab.ClPtr THEN
- 1674                                                SemError(219)
- 1675                                              END; .) .
- 1676    (* WITH pushes each record's fields (inner wins) plus its base
- 1677       address; field designators resolve through both stacks. *)
- 1678    WithStat                              (. VAR nW: CARDINAL;
- 1679                                               astNode: AST.Node; .)
- 1680      = "WITH"                            (. nW := 0;
- 1681                                             astNode := AST.MakeNode(AST.NkWith); .)
- 1682        WithItem<nW, astNode> { "," WithItem<nW, astNode> }
- 1683        "DO"                              (. astStmt := AST.NoNode; .)
- 1684        [ StatSeq ] "END"                 (. AST.SetChild(astNode,
- 1685                                             AST.NChild(astNode), astStmt);
- 1686                                             astStmt := astNode;
- 1687                                             WHILE nW > 0 DO
- 1688                                               SymTab.PopScope;
- 1689                                               QbeGen.PopWith;
- 1690                                               DEC(nW)
- 1691                                             END; .) .
- 1692    WithItem<VAR nW: CARDINAL; wnode: AST.Node>
- 1693                                          (. VAR dt: SymTab.TypeIndex;
- 1694                                               dk: INTEGER;
- 1695                                               qd, qe: QbeGen.QVal;
- 1696                                               qn: SymTab.Name;
- 1697                                               sfx: BOOLEAN; .)
- 1698      = Design<dt, dk, qd, qn, sfx>
- 1699                                          (. IF astCur # AST.NoNode THEN
- 1700                                               AST.SetChild(wnode,
- 1701                                                 AST.NChild(wnode), astCur) END;
- 1702                                             IF dt = SymTab.InvalidType THEN
- 1703                                             ELSIF (SymTab.ClassOf(dt) #
- 1704                                                    SymTab.ClRecord)
- 1705   AND (SymTab.ClassOf(dt) #
- 1706                                                   SymTab.ClClass) THEN
- 1707                                               SemError(215)
- 1708                                             ELSIF SymTab.PushRecord(dt) THEN
- 1709                                               QbeGen.PushWith(qd);
- 1710                                               INC(nW)
- 1711                                             END; .) .
- 1712    (* Assignment or procedure-statement call (4.1, module level).
- 1713       Bare `P;` is a syntax error; function-as-statement is 233. *)
- 1714    AssOrCall                             (. VAR dt, et: SymTab.TypeIndex;
- 1715                                               dk: INTEGER;
- 1716                                               qd, qe, qt, ql: QbeGen.QVal;
- 1717                                               qn: SymTab.Name;
- 1718                                               ct2, res0: SymTab.TypeIndex;
- 1719                                               q2, mg0: QbeGen.QVal;
- 1720                                               isR, conv, wconv: BOOLEAN;
- 1721                                               called, sfx: BOOLEAN;
- 1722                                               astLhs, astRes: AST.Node; mname: SymTab.Name; isM: BOOLEAN;
- 1723                                               n: SymTab.Name; astLab, astNode: AST.Node; .)
- 1724      = GetIdent<n>
- 1725        ( ":"                             (. NoteLabel(n);
- 1726                                             astNode := AST.MakeNode(AST.NkLabel);
- 1727                                             AST.SetChild(astNode, 0,
- 1728                                               AST.MakeLeaf(AST.NkIdent, n));
- 1729                                             astLab := AST.MakeNode(AST.NkBlock);
- 1730                                             AST.SetChild(astLab, 0, astNode); .)
- 1731          Statement                       (. IF astStmt # AST.NoNode THEN
- 1732                                               AST.SetChild(astLab, 1, astStmt) END;
- 1733                                             astStmt := astLab; .)
- 1734        | DesignTail<n, dt, dk, qd, qn, sfx>
- 1735        (. astLhs := astCur; astNArgs := 0; .)
- 1736        ( ":="
- 1737          Expr<et, qe>                    (. astStmt := AST.MakeBin(
- 1738                                               AST.NkAssign, 0, astLhs, astCur);
- 1739                                             IF (dt # SymTab.InvalidType)
- 1740   AND (dk # SymTab.KindVar)
- 1741   AND (dk # SymTab.KindParam)
- 1742   AND (dk # SymTab.KindField) THEN
- 1743                                             SemError(210)
- 1744                                           ELSIF NOT SymTab.Assignable(et,
- 1745                                                    dt) THEN
- 1746                                             SemError(210)
- 1747                                           ELSIF (dt # SymTab.InvalidType)
- 1748   AND (SymTab.ClassOf(dt) =
- 1749                                                 SymTab.ClClass) THEN
- 1750                                             SemError(230) END;
- 1751                                           isR := (dt #
- 1752                                                   SymTab.InvalidType)
- 1753   AND (SymTab.ClassOf(dt)
- 1754                                                     = SymTab.ClReal);
- 1755                                           conv := isR
- 1756   AND SymTab.IsIntFamily(et);
- 1757                                           wconv := (dt #
- 1758                                                     SymTab.InvalidType)
- 1759   AND SymTab.IsLongFamily(dt)
- 1760   AND SymTab.IsIntFamily(et);
- 1761                                           IF ((dk = SymTab.KindVar)
- 1762                                               OR (dk = SymTab.KindParam)
- 1763                                               OR (dk = SymTab.KindField))
- 1764   AND (dt # SymTab.InvalidType)
- 1765   AND (et # SymTab.InvalidType)
- 1766   AND (SymTab.ClassOf(dt) #
- 1767                                                 SymTab.ClClass) THEN
- 1768                                           END; .)
- 1769        | ArgList<qn, dt, qd, TRUE, TRUE, methCls, ct2, q2, called>
- 1770                                          (. astRes := AstCallNode(astLhs);
- 1771                                             sfx := FALSE; .)
- 1772          ( { ResultComp<ct2, q2, sfx, astRes, mname, methCls, isM> }
- 1773            ":=" Expr<et, qe>             (. astStmt := AST.MakeBin(
- 1774                                               AST.NkAssign, 0, astRes, astCur);
- 1775                                             IF NOT sfx THEN
- 1776                                               SemError(233)
- 1777                                             ELSIF (ct2 # SymTab.InvalidType)
- 1778    AND NOT SymTab.Assignable(et, ct2) THEN
- 1779                                               SemError(210)
- 1780                                             END; .)
- 1781          |                               (. IF ct2 #
- 1782                                               SymTab.InvalidType THEN
- 1783                                               SemError(233) END;
- 1784                                             astStmt := astRes; .) )
- 1785        |                                 (* bare `P;`: proper parameterless
- 1786                                              procedure call; anything else
- 1787                                              here is 233 (was a bare syntax
- 1788                                              error before 4.2) *)
- 1789                                          (. astStmt := AstCallNode(astLhs);
- 1790                                              IF (dk = SymTab.KindProc)
- 1791   AND NOT sfx THEN
- 1792                                               res0 := SymTab.ProcRes(qn);
- 1793                                               IF res0 #
- 1794                                                  SymTab.InvalidType THEN
- 1795                                                 SemError(233)
- 1796                                               ELSIF SymTab.ProcNPar(qn) #
- 1797                                                       0 THEN
- 1798                                                 SemError(233)
- 1799                                               END
- 1800                                             ELSE SemError(233)
- 1801                                              END; .) ) ) .
- 1802    (* Actual-parameter list shared by statement and expression calls.
- 1803       want selects CallEnd's result handling; t/q carry the call
- 1804       value (statement calls discard). Arity/type failures are 233;
- 1805       evaluation code still emits so the .ssa stays assembleable. *)
- 1806    ArgList<pn: SymTab.Name; pt: SymTab.TypeIndex; callee: QbeGen.QVal;
- 1807            want: BOOLEAN; soft: BOOLEAN; methCls: SymTab.TypeIndex;
- 1808            VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal;
- 1809            VAR called: BOOLEAN>          (. VAR i, np: CARDINAL;
- 1810                                               vs: INTEGER;
- 1811                                               res: SymTab.TypeIndex;
- 1812                                               mg: QbeGen.QVal;
- 1813                                               ok, ind, isMeth, va: BOOLEAN; .)
- 1814      = "("                               (. called := TRUE;
- 1815                                             ok := TRUE;
- 1816                                             ind := FALSE;
- 1817                                             isMeth := methCls #
- 1818                                               SymTab.InvalidType;
- 1819                                             IF isMeth THEN
- 1820                                               res := SymTab.ClassMethodRes(methCls, pn)
- 1821                                             ELSIF SymTab.SymKind(pn) = SymTab.KindProc THEN
- 1822                                               res := SymTab.ProcRes(pn)
- 1823                                             ELSIF (pt # SymTab.InvalidType)
- 1824    AND (SymTab.ClassOf(pt) = SymTab.ClProc) THEN
- 1825                                               ind := TRUE;
- 1826                                               res := SymTab.ProcTypeRes(pt)
- 1827                                             ELSE SemError(233);
- 1828                                               ok := FALSE;
- 1829                                               res := SymTab.InvalidType
- 1830                                             END;
- 1831                                             i := 0; .)
- 1832        [ ActParam<pn, pt, ind, methCls, i>        (. INC(i); .)
- 1833          { "," ActParam<pn, pt, ind, methCls, i>  (. INC(i); .) } ]
- 1834        ")"                               (. IF ok THEN
- 1835                                               IF isMeth THEN
- 1836                                                 np := SymTab.ClassMethodNPar(
- 1837                                                   methCls, pn)
- 1838                                               ELSIF ind THEN
- 1839                                                 np := SymTab.ProcTypeNPar(pt)
- 1840                                               ELSE np := SymTab.ProcNPar(pn)
- 1841                                               END;
- 1842                                               va := (NOT isMeth) AND (NOT ind)
- 1843                                                 AND (SymTab.SymKind(pn) =
- 1844                                                      SymTab.KindProc)
- 1845                                                 AND SymTab.Varargs(pn);
- 1846                                               IF (i # np) AND NOT va THEN
- 1847                                                 SemError(233); ok := FALSE
- 1848                                               END
- 1849                                             END;
- 1850                                             IF NOT ok THEN
- 1851                                               t := SymTab.InvalidType;
- 1852                                               QbeGen.CopyOp("0", q)
- 1853                                             ELSIF want THEN
- 1854                                               IF res =
- 1855                                                  SymTab.InvalidType THEN
- 1856                                                 IF NOT soft THEN SemError(233) END;
- 1857                                                 t := SymTab.InvalidType;
- 1858                                                 QbeGen.CopyOp("0", q)
- 1859                                               ELSE t := res;
- 1860                                                  QbeGen.CopyOp("@", q)
- 1861                                               END
- 1862                                             ELSE
- 1863                                               IF res #
- 1864                                                  SymTab.InvalidType THEN
- 1865                                                 SemError(233)
- 1866                                               END;
- 1867                                               t := SymTab.InvalidType;
- 1868                                               QbeGen.CopyOp("0", q);
- 1869                                             END; .) .
- 1870    (* One actual: VAR formals take recorded designator addresses
- 1871       (233 otherwise); value formals take converted expressions. *)
- 1872    ActParam<pn: SymTab.Name; pt: SymTab.TypeIndex; ind: BOOLEAN;
- 1873             methCls: SymTab.TypeIndex; i: CARDINAL>
- 1874                                          (. VAR at, ft: SymTab.TypeIndex;
- 1875                                               qe, qa, qt: QbeGen.QVal;
- 1876                                               isV, conv, va: BOOLEAN;
- 1877                                               cl: CHAR;
- 1878                                               savedN, aj: CARDINAL;
- 1879                                               savedArgs: ARRAY [0 .. 31]
- 1880                                                 OF AST.Node;
- 1881                                               astActual: AST.Node; .)
- 1882      =                                   (. (* Parsing the actual can clobber
- 1883                                               the enclosing call's argument
- 1884                                               list (Factor resets astNArgs),
- 1885                                               so save/restore it. *)
- 1886                                             savedN := astNArgs; aj := 0;
- 1887                                             WHILE aj <= HIGH(astArgs) DO
- 1888                                               savedArgs[aj] := astArgs[aj];
- 1889                                               INC(aj)
- 1890                                             END; .)
- 1891        Expr<at, qe>                      (. astActual := astCur;
- 1892                                             astNArgs := savedN; aj := 0;
- 1893                                             WHILE aj <= HIGH(astArgs) DO
- 1894                                               astArgs[aj] := savedArgs[aj];
- 1895                                               INC(aj)
- 1896                                             END;
- 1897                                             IF astNArgs <= HIGH(astArgs) THEN
- 1898                                               astArgs[astNArgs] := astCur;
- 1899                                               INC(astNArgs)
- 1900                                             END;
- 1901                                             va := (NOT ind)
- 1902                                               AND (methCls =
- 1903                                                  SymTab.InvalidType)
- 1904                                               AND (SymTab.SymKind(pn) =
- 1905                                                  SymTab.KindProc)
- 1906                                               AND SymTab.Varargs(pn);
- 1907                                             IF ind THEN
- 1908                                               ft :=
- 1909                                                 SymTab.ProcTypeParamType(pt,
- 1910                                                   i);
- 1911                                               isV :=
- 1912                                                 SymTab.ProcTypeParamIsVar(pt,
- 1913                                                   i)
- 1914                                             ELSIF methCls #
- 1915                                                SymTab.InvalidType THEN
- 1916                                               ft :=
- 1917                                                 SymTab.ClassMethodParamType(
- 1918                                                 methCls, pn, i);
- 1919                                               isV :=
- 1920                                                 SymTab.ClassMethodParamIsVar(
- 1921                                                 methCls, pn, i)
- 1922                                             ELSE
- 1923                                               ft := SymTab.ParamType(pn, i);
- 1924                                               isV := SymTab.ParamIsVar(pn, i)
- 1925                                             END;
- 1926                                             IF (at = SymTab.InvalidType) THEN
- 1927                                             ELSIF ft = SymTab.InvalidType THEN
- 1928                                             ELSIF isV THEN
- 1929                                               IF (SymTab.ClassOf(at) = SymTab.ClChar)
- 1930    AND (SymTab.ClassOf(ft) = SymTab.ClArray)
- 1931    AND (SymTab.ClassOf(SymTab.ArrayElem(ft)) = SymTab.ClChar)
- 1932    AND QbeGen.IsImm(qe) THEN
- 1933                                               ELSIF (AST.Kind(astActual) #
- 1934                                                      AST.NkDesignator)
- 1935    AND (AST.Kind(astActual) # AST.NkStrLit) THEN
- 1936                                                 SemError(233)
- 1937                                               ELSIF NOT SymTab.VarParamOk(at, ft) THEN
- 1938                                                 SemError(233)
- 1939                                               END
- 1940                                             ELSE
- 1941                                               IF (SymTab.ClassOf(at) = SymTab.ClChar)
- 1942    AND (SymTab.ClassOf(ft) = SymTab.ClArray)
- 1943    AND (SymTab.ClassOf(SymTab.ArrayElem(ft)) = SymTab.ClChar)
- 1944    AND QbeGen.IsImm(qe) THEN
- 1945                                               ELSIF NOT SymTab.Assignable(at, ft) THEN
- 1946                                                 SemError(233)
- 1947                                               END
- 1948                                             END; .) .
- 1949    IfStat                                (. VAR t: SymTab.TypeIndex;
- 1950                                               q: QbeGen.QVal;
- 1951                                               hasElse: BOOLEAN;
- 1952                                               astCond, astIf, astLast,
- 1953                                               astNode: AST.Node; .)
- 1954      = "IF" (. hasElse := FALSE; .)
- 1955        Expr<t, q> (. astCond := astCur; astStmt := AST.NoNode;
- 1956                                             IF NOT SymTab.BoolCheck(t) THEN
- 1957                                               SemError(214) END; .)
- 1958        "THEN" [ StatSeq ]                (. astNode := AST.MakeNode(AST.NkIf);
- 1959                                             AST.SetChild(astNode, 0, astCond);
- 1960                                             AST.SetChild(astNode, 1, astStmt);
- 1961                                             astIf := astNode;
- 1962                                             astLast := astNode; .)
- 1963        { "ELSIF"
- 1964          Expr<t, q> (. astCond := astCur; astStmt := AST.NoNode;
- 1965                                             IF NOT SymTab.BoolCheck(t) THEN
- 1966                                               SemError(214) END; .)
- 1967          "THEN" [ StatSeq ]              (. astNode := AST.MakeNode(AST.NkIf);
- 1968                                             AST.SetChild(astNode, 0, astCond);
- 1969                                             AST.SetChild(astNode, 1, astStmt);
- 1970                                             AST.SetChild(astLast, 2, astNode);
- 1971                                             astLast := astNode; .) }
- 1972        [ "ELSE"                          (. hasElse := TRUE;
- 1973                                             astStmt := AST.NoNode; .)
- 1974          [ StatSeq ] (. AST.SetChild(astLast, 2, astStmt); .) ]
- 1975        "END" (. astStmt := astIf; .) .
- 1976    WhileStat                             (. VAR t: SymTab.TypeIndex;
- 1977                                               q: QbeGen.QVal;
- 1978                                               astCond, astNode: AST.Node; .)
- 1979      = "WHILE" (. astStmt := AST.NoNode; .)
- 1980        Expr<t, q> (. astCond := astCur;
- 1981                                             IF NOT SymTab.BoolCheck(t) THEN
- 1982                                               SemError(214) END; .)
- 1983        "DO" [ StatSeq ]                  (. astNode := AST.MakeNode(AST.NkWhile);
- 1984                                             AST.SetChild(astNode, 0, astCond);
- 1985                                             AST.SetChild(astNode, 1, astStmt);
- 1986                                             astStmt := astNode; .)
- 1987        "END" .
- 1988    RepeatStat                            (. VAR t: SymTab.TypeIndex;
- 1989                                               q: QbeGen.QVal;
- 1990                                               astCond, astBody, astNode:
- 1991                                                 AST.Node; .)
- 1992      = "REPEAT" (. astStmt := AST.NoNode; .)
- 1993        [ StatSeq ] (. astBody := astStmt; .)
- 1994        "UNTIL" Expr<t, q> (. astCond := astCur;
- 1995                                             astNode := AST.MakeNode(AST.NkRepeat);
- 1996                                             AST.SetChild(astNode, 0, astBody);
- 1997                                             AST.SetChild(astNode, 1, astCond);
- 1998                                             astStmt := astNode;
- 1999                                             IF NOT SymTab.BoolCheck(t) THEN
- 2000                                               SemError(214) END; .) .
- 2001    LoopStat                              (. VAR lEnd: QbeGen.QVal; astNode: AST.Node; .)
- 2002      = "LOOP"                            (. astStmt := AST.NoNode;
- 2003                                             QbeGen.NewLabel(lEnd);
- 2004                                             QbeGen.PushLoop(lEnd); .)
- 2005        [ StatSeq ]
- 2006        "END"                             (. astNode := AST.MakeNode(AST.NkLoop);
- 2007                                             AST.SetChild(astNode, 0, astStmt);
- 2008                                             astStmt := astNode;
- 2009                                             QbeGen.PopLoop; .) .
- 2010    (* FOR with static-sign BY (literal, non-zero; 220 otherwise).
- 2011       Runtime direction would need a compare-select; the literal
- 2012       sign picks cslew/csegew at "DO" time. *)
- 2013    ForStat                               (. VAR lv: SymTab.Name;
- 2014                                               tlo, thi, tby:
- 2015                                                 SymTab.TypeIndex;
- 2016                                               qlo, qhi, qby, qt, qk, qb:
- 2017                                                 QbeGen.QVal;
- 2018                                               lTop, lBody, lEnd:
- 2019                                                 QbeGen.QVal;
- 2020                                               by: INTEGER;
- 2021                                               ok: BOOLEAN;
- 2022                                               astVar, astLo, astHi, astBy,
- 2023                                               astNode: AST.Node; .)
- 2024      = "FOR"                             (. by := 1; .)
- 2025        GetIdent<lv> (. astVar := AST.MakeLeaf(AST.NkIdent, lv);
- 2026                                             astStmt := AST.NoNode;
- 2027                                             astBy := AST.NoNode;
- 2028                                             ok := SymTab.Lookup(lv);
- 2029                                             IF NOT ok THEN
- 2030                                               SemError(201)
- 2031                                             ELSIF (SymTab.SymKind(lv) #
- 2032                                                    SymTab.KindVar)
- 2033   AND (SymTab.SymKind(lv) #
- 2034                                                   SymTab.KindParam) THEN
- 2035                                               SemError(220); ok := FALSE
- 2036                                             ELSIF NOT SymTab.IsIntFamily(
- 2037                                                     SymTab.SymType(lv)) THEN
- 2038                                               SemError(220); ok := FALSE
- 2039                                             END; .)
- 2040        ":=" Expr<tlo, qlo> (. astLo := astCur;
- 2041                                             IF NOT SymTab.IsIntFamily(tlo) THEN
- 2042                                               SemError(220); ok := FALSE
- 2043                                             END; .)
- 2044        "TO" Expr<thi, qhi> (. astHi := astCur;
- 2045                                             IF NOT SymTab.IsIntFamily(thi) THEN
- 2046                                               SemError(220); ok := FALSE
- 2047                                             END; .)
- 2048        [ "BY" Expr<tby, qby> (. astBy := astCur;
- 2049                                             IF (tby #
- 2050                                               SymTab.InvalidType)
- 2051   AND NOT SymTab.IsIntFamily(tby) THEN
- 2052                                               SemError(220); ok := FALSE
- 2053                                             END;
- 2054                                             IF NOT SymTab.ConstInt(qby, by) THEN
- 2055                                               SemError(230); by := 1
- 2056                                             ELSIF by = 0 THEN
- 2057                                               SemError(220); by := 1
- 2058                                             END; .) ]
- 2059        "DO"
- 2060        [ StatSeq ]
- 2061        "END" (. astNode := AST.MakeNode(AST.NkFor);
- 2062                                             AST.SetChild(astNode, 0, astVar);
- 2063                                             AST.SetChild(astNode, 1, astLo);
- 2064                                             AST.SetChild(astNode, 2, astHi);
- 2065                                             AST.SetChild(astNode, 3, astBy);
- 2066                                             AST.SetChild(astNode, 4, astStmt);
- 2067                                             astStmt := astNode;
- 2068                                             .) .
- 2069    CaseStat                              (. VAR tsel: SymTab.TypeIndex;
- 2070                                               qsel, lEnd: QbeGen.QVal;
- 2071                                               arm, astNode, astArms,
- 2072                                               astArmsTail: AST.Node; .)
- 2073      = "CASE" Expr<tsel, qsel>           (. astNode := AST.MakeNode(AST.NkCase);
- 2074                                             AST.SetChild(astNode, 0, astCur);
- 2075                                             astArms := AST.NoNode;
- 2076                                             astArmsTail := AST.NoNode;
- 2077                                             .)
- 2078        "OF" CaseAlt<tsel, qsel, lEnd, astArms, astArmsTail>
- 2079        { "|" CaseAlt<tsel, qsel, lEnd, astArms, astArmsTail> }
- 2080        [ "ELSE"                          (. astStmt := AST.NoNode; .)
- 2081          [ StatSeq ]                     (. arm := AST.MakeNode(AST.NkCaseArm);
- 2082                                             AST.SetOp(arm, 1);
- 2083                                             AST.SetChild(arm, 0, astStmt);
- 2084                                             AstAppend(AST.NkBlock,
- 2085                                               astArms, astArmsTail, arm); .) ]
- 2086        "END"                             (. AST.SetChild(astNode, 1, astArms);
- 2087                                             astStmt := astNode;
- 2088                                             .) .
- 2089    (* Compare-chain lowering: each alternative ends its match-tests
- 2090       with "jmp lAfter", so the no-match fallthrough skips the body:
- 2091       "cmp; jnz(lBody,lF); lF: ... ; jmp lAfter; lBody: S; jmp lEnd;
- 2092       lAfter:". Falls into the next alternative, ELSE, or END. *)
- 2093    CaseAlt<tsel: SymTab.TypeIndex; qsel: QbeGen.QVal;
- 2094            lEnd: QbeGen.QVal; VAR arms, armsTail: AST.Node>
- 2095                                          (. VAR arm: AST.Node; .)
- 2096      =                                   (. arm := AST.MakeNode(AST.NkCaseArm); .)
- 2097        CaseLabel<tsel, qsel, arm>
- 2098        { "," CaseLabel<tsel, qsel, arm> }
- 2099        ":"                               (. astStmt := AST.NoNode; .)
- 2100        [ StatSeq ]                       (. AST.SetChild(arm, AST.NChild(arm),
- 2101                                             astStmt);
- 2102                                             AstAppend(AST.NkBlock,
- 2103                                               arms, armsTail, arm);
- 2104                                             .) .
- 2105    CaseLabel<tsel: SymTab.TypeIndex; qsel: QbeGen.QVal;
- 2106              arm: AST.Node>
- 2107                                          (. VAR t2, t3: SymTab.TypeIndex;
- 2108                                               q2, q3, qc, qd, qe:
- 2109                                                 QbeGen.QVal;
- 2110                                               astLab: AST.Node;
- 2111                                               lNext: QbeGen.QVal; .)
- 2112      = Expr<t2, q2> (. astLab := astCur;
- 2113                                             IF (t2 #
- 2114                                               SymTab.InvalidType)
- 2115   AND (tsel #
- 2116                                                 SymTab.InvalidType)
- 2117   AND ((SymTab.ClassOf(t2) =
- 2118                                                  SymTab.ClSet)
- 2119                                                 OR (SymTab.ClassOf(tsel) =
- 2120                                                     SymTab.ClSet)) THEN
- 2121                                               SemError(230)
- 2122                                             ELSIF (t2 #
- 2123                                               SymTab.InvalidType)
- 2124   AND (tsel #
- 2125                                                 SymTab.InvalidType)
- 2126   AND NOT SymTab.EqCheck(t2,
- 2127                                                   tsel) THEN
- 2128                                               SemError(213) END;
- 2129                                                 IF NOT QbeGen.IsImm(q2) THEN
- 2130                                                   SemError(230)
- 2131                                                 END; .)
- 2132        [ ".." Expr<t3, q3>               (. astLab := AST.MakeBin(
- 2133                                               AST.NkSubrange, 0, astLab, astCur);
- 2134                                             IF (t3 #
- 2135                                               SymTab.InvalidType)
- 2136   AND (tsel #
- 2137                                                 SymTab.InvalidType)
- 2138   AND NOT SymTab.EqCheck(t3,
- 2139                                                   tsel) THEN
- 2140                                               SemError(213) END;
- 2141                                                 IF NOT QbeGen.IsImm(q3) THEN
- 2142                                                   SemError(230)
- 2143                                                 END; .) ]
- 2144                                          (. AST.SetChild(arm,
- 2145                                               AST.NChild(arm), astLab); .) .
- 2146    ReturnStat                            (. VAR t: SymTab.TypeIndex;
- 2147                                               q, qt: QbeGen.QVal;
- 2148                                               res: SymTab.TypeIndex;
- 2149                                               hadE, conv: BOOLEAN;
- 2150                                               astVal, astNode: AST.Node; .)
- 2151      = "RETURN"                          (. hadE := FALSE; astStmt := AST.NoNode; .)
- 2152        [ Expr<t, q> (. hadE := TRUE; astVal := astCur; .) ]
- 2153                                          (. astNode := AST.MakeNode(AST.NkReturn);
- 2154                                             IF hadE THEN
- 2155                                               AST.SetChild(astNode, 0, astVal)
- 2156                                             END;
- 2157                                             astStmt := astNode;
- 2158                                             conv := FALSE;
- 2159                                             IF NOT SymTab.InProc() THEN
- 2160                                               SemError(232)
- 2161                                             ELSE res := SymTab.CurRes();
- 2162                                               IF NOT hadE THEN
- 2163                                                 IF res #
- 2164                                                    SymTab.InvalidType THEN
- 2165                                                   SemError(232)
- 2166                                                 END
- 2167                                               ELSIF (res =
- 2168                                                      SymTab.InvalidType)
- 2169                                                  OR (t #
- 2170                                                      SymTab.InvalidType)
- 2171   AND NOT SymTab.Assignable(t,
- 2172                                                       res) THEN
- 2173                                                 SemError(232)
- 2174                                             END
- 2175                                             END; .) .
- 2176    HaltStat                              (. VAR t: SymTab.TypeIndex;
- 2177                                               q: QbeGen.QVal;
- 2178                                               astVal, astNode: AST.Node; .)
- 2179      = "HALT" (. astVal := AST.NoNode; .)
- 2180        [ "(" Expr<t, q> (. astVal := astCur; .) ")" ]
- 2181                                          (. astNode := AST.MakeNode(AST.NkHalt);
- 2182                                             IF astVal # AST.NoNode THEN
- 2183                                               AST.SetChild(astNode, 0, astVal)
- 2184                                             END;
- 2185                                             astStmt := astNode;
- 2186                                             .) .
- 2187    (* Designator: scalar loads, array addresses, and index suffixes.
- 2188       Each index descends one level (bounds-checked, trap on breach);
- 2189       nested levels reload the inner descriptor address. q ends as the
- 2190       value (scalars), the descriptor address (plain arrays), or the
- 2191       element address (indexed); sfx marks the indexed form. *)
- 2192    Design<VAR t: SymTab.TypeIndex; VAR k: INTEGER;
- 2193           VAR q: QbeGen.QVal; VAR qn: SymTab.Name; VAR sfx: BOOLEAN>
- 2194                                          (. VAR n: SymTab.Name; .)
- 2195      = GetIdent<n> DesignTail<n, t, k, q, qn, sfx> .
- 2196    (* The part of Design after the identifier: resolve it and walk the
- 2197       selectors.  Split out so a statement can decide between a label
- 2198       (`ident :`) and a designator (`ident := ...`) with one token. *)
- 2199    DesignTail<VAR n: SymTab.Name; VAR t: SymTab.TypeIndex; VAR k: INTEGER;
- 2200           VAR q: QbeGen.QVal; VAR qn: SymTab.Name; VAR sfx: BOOLEAN>
- 2201                                          (. VAR fn, mal: SymTab.Name;
- 2202                                               cls: INTEGER;
- 2203                                               ic: SymTab.TypeIndex;
- 2204                                               curT, it, eT, bt:
- 2205                                                 SymTab.TypeIndex;
- 2206                                               iq, ql, qlo, qhi, qe:
- 2207                                                 QbeGen.QVal;
- 2208                                               lo, hi: INTEGER;
- 2209                                               fo: INTEGER;
- 2210                                               isOpen: BOOLEAN;
- 2211                                               qb, cv: QbeGen.QVal;
- 2212                                               fid, fref: INTEGER;
- 2213                                               r: BOOLEAN;
- 2214                                                astDes, astSel: AST.Node;
- 2215                                               fwd: BOOLEAN; .)
- 2216      =                                   (. methCls := SymTab.InvalidType;
- 2217                                             QbeGen.CopyOp(n, qn);
- 2218                                             sfx := FALSE; fwd := FALSE;
- 2219                                             fid := 0; fref := 0;
- 2220                                             IF NOT SymTab.Lookup(n) THEN
- 2221                                               (* a bare method name inside
- 2222                                                  a CLASS IMPLEMENTATION
- 2223                                                  is a sibling call on
- 2224                                                  THIS *)
- 2225                                               ic := SymTab.CurImplClass();
- 2226                                               IF (ic #
- 2227                                                  SymTab.InvalidType)
- 2228    AND SymTab.MethodExists(ic, n) THEN
- 2229                                                 sfx := FALSE;
- 2230                                                  QbeGen.CopyOp("@", q);
- 2231                                                 methCls := ic;
- 2232                                                 k := SymTab.KindProc;
- 2233                                                 t := SymTab.InvalidType
- 2234                                               ELSIF SymTab.InProc() THEN
- 2235                                                 (* not declared yet: a
- 2236                                                    forward reference to a
- 2237                                                    module-level variable
- 2238                                                    declared further down. *)
- 2239                                                 k := SymTab.KindVar;
- 2240                                                 r := SymTab.FwdVarRef(n, k,
- 2241                                                   fref, t);
- 2242                                                  QbeGen.CopyOp("@", q);
- 2243                                                 sfx := TRUE; fwd := TRUE
- 2244                                               ELSE
- 2245                                                 SemError(201);
- 2246                                                 t :=
- 2247                                                   SymTab.InvalidType;
- 2248                                                 k := -1;
- 2249                                                 QbeGen.CopyOp("0", q)
- 2250                                               END
- 2251                                             ELSE
- 2252                                               t := SymTab.SymType(n);
- 2253                                               k := SymTab.SymKind(n);
- 2254                                               IF k = SymTab.KindConst THEN
- 2255                                                 IF SymTab.Equal(n,
- 2256                                                    "TRUE") THEN
- 2257                                                   t := SymTab.BoolType();
- 2258                                                   QbeGen.CopyOp("1", q)
- 2259                                                 ELSIF SymTab.Equal(n,
- 2260                                                    "FALSE") THEN
- 2261                                                   t := SymTab.BoolType();
- 2262                                                   QbeGen.CopyOp("0", q)
- 2263                                                 ELSIF SymTab.Equal(n,
- 2264                                                    "NIL") THEN
- 2265                                                   QbeGen.CopyOp("0", q)
- 2266                                                 ELSE
- 2267                                                   cls :=
- 2268                                                     SymTab.ClassOf(t);
- 2269                                                   IF (t #
- 2270                                                       SymTab.InvalidType)
- 2271   AND ((cls = SymTab.ClInt)
- 2272                                                      OR (cls
- 2273                                                          = SymTab.ClChar)
- 2274                                                      OR (cls
- 2275                                                          = SymTab.ClEnum)
- 2276                                                      OR (cls
- 2277                                                          = SymTab.ClReal)
- 2278                                                      OR (cls
- 2279                                                          = SymTab.ClLong)
- 2280                                                      OR (cls
- 2281                                                          = SymTab.ClNil)) THEN
- 2282                                                     IF cls = SymTab.ClNil THEN
- 2283                                                       QbeGen.CopyOp("0", q)
- 2284                                                     ELSIF ((cls
- 2285                                                         = SymTab.ClInt)
- 2286                                                       OR (cls
- 2287                                                         = SymTab.ClChar)
- 2288                                                       OR (cls
- 2289                                                         = SymTab.ClEnum)
- 2290                                                       OR (cls
- 2291                                                         = SymTab.ClLong))
- 2292    AND SymTab.GetSymVal(n, cv)
- 2293    AND QbeGen.IsImm(cv) THEN
- 2294                                                       QbeGen.CopyOp(cv, q)
- 2295                                                     ELSE
- 2296                                                       QbeGen.LoadVar(n,
- 2297                                                         cls = SymTab.ClReal,
- 2298                                                         q)
- 2299                                                     END
- 2300                                                   ELSIF (cls = SymTab.ClArray)
- 2301                                                      OR (cls = SymTab.ClRecord)
- 2302                                                      OR (cls = SymTab.ClClass)
- 2303                                                      OR (cls = SymTab.ClStr)
- 2304                                                      OR (cls = SymTab.ClUStr) THEN
- 2305                                                     (* aggregate constant:
- 2306                                                        its value IS the
- 2307                                                        descriptor address *)
- 2308                                                     IF SymTab.GetSymVal(n, cv) THEN
- 2309                                                       QbeGen.CopyOp(cv, q)
- 2310                                                     ELSE
- 2311                                                       QbeGen.CopyOp("0", q)
- 2312                                                     END
- 2313                                                   ELSE
- 2314                                                     IF t #
- 2315                                                        SymTab.InvalidType THEN
- 2316                                                       SemError(230)
- 2317                                                     END;
- 2318                                                     QbeGen.CopyOp("0", q)
- 2319                                                   END
- 2320                                                 END
- 2321                                               ELSIF (k = SymTab.KindVar)
- 2322                                                  OR (k = SymTab.KindParam) THEN
- 2323                                                 cls := SymTab.ClassOf(t);
- 2324                                                 IF (cls # SymTab.ClInt)
- 2325                                                    AND (cls # SymTab.ClBool)
- 2326                                                    AND (cls # SymTab.ClChar)
- 2327                                                    AND (cls # SymTab.ClUChar)
- 2328                                                    AND (cls # SymTab.ClEnum)
- 2329                                                    AND (cls # SymTab.ClReal)
- 2330                                                    AND (cls # SymTab.ClPtr)
- 2331                                                    AND (cls # SymTab.ClProc)
- 2332                                                    AND (cls # SymTab.ClLong)
- 2333                                                    AND (cls # SymTab.ClArray)
- 2334                                                    AND (cls # SymTab.ClSet)
- 2335                                                    AND (cls # SymTab.ClRecord)
- 2336                                                    AND (cls # SymTab.ClUStr)
- 2337                                                    AND (cls # SymTab.ClClass) THEN
- 2338                                                   SemError(230);
- 2339                                                   QbeGen.CopyOp("0", q)
- 2340                                                 ELSE QbeGen.CopyOp("@", q)
- 2341                                                 END
- 2342                                               ELSE QbeGen.CopyOp("0", q);
- 2343                                                 IF k = SymTab.KindImport THEN
- 2344                                                   SemError(230)
- 2345                                                 ELSIF k =
- 2346                                                    SymTab.KindProc THEN
- 2347                                                   (* bare procedure name:
- 2348                                                      a following ArgList
- 2349                                                      makes it a call;
- 2350                                                      otherwise Fact
- 2351                                                      reports 230 *)
- 2352                                                 ELSE
- 2353                                                    IF k = SymTab.KindField THEN
- 2354                                                      IF QbeGen.TopWith(qb) THEN
- 2355                                                        sfx := TRUE
- 2356                                                      ELSE SemError(230);
- 2357                                                        QbeGen.CopyOp("0", q)
- 2358                                                      END
- 2359                                                    END
- 2360                                                 END
- 2361                                               END
- 2362                                             END; .)
- 2363        (. astDes := AST.MakeNode(AST.NkDesignator);
- 2364           AST.SetChild(astDes, AST.NChild(astDes), AST.MakeLeaf(AST.NkIdent, n));
- 2365           IF fwd THEN AST.SetOp(astDes, 1) END;
- 2366            IF fwd THEN Check.NoteForward(fref, astDes) END; .)
- 2367        { "[" Expr<it, iq>
- 2368                                          (. AST.SetChild(astDes, AST.NChild(astDes),
- 2369               AST.MakeUn(AST.NkSelector, AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
- 2370                                             ELSIF SymTab.ClassOf(t) #
- 2371                                                   SymTab.ClArray THEN
- 2372                                               SemError(217);
- 2373                                               t := SymTab.InvalidType
- 2374                                             ELSIF NOT SymTab.IsIntFamily(it)
- 2375   AND (SymTab.ClassOf(it) #
- 2376                                                   SymTab.ClChar)
- 2377   AND (SymTab.ClassOf(it) #
- 2378                                                   SymTab.ClEnum) THEN
- 2379                                               SemError(218);
- 2380                                               t := SymTab.InvalidType
- 2381                                              ELSE
- 2382                                                eT := SymTab.ArrayElem(t);
- 2383                                                t := eT; sfx := TRUE
- 2384                                              END; .)
- 2385          { "," Expr<it, iq>
- 2386                                          (. AST.SetChild(astDes, AST.NChild(astDes),
- 2387               AST.MakeUn(AST.NkSelector, AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
- 2388                                             ELSIF SymTab.ClassOf(t) #
- 2389                                                   SymTab.ClArray THEN
- 2390                                               SemError(217);
- 2391                                               t := SymTab.InvalidType
- 2392                                             ELSIF NOT SymTab.IsIntFamily(it)
- 2393   AND (SymTab.ClassOf(it) #
- 2394                                                   SymTab.ClChar)
- 2395   AND (SymTab.ClassOf(it) #
- 2396                                                   SymTab.ClEnum) THEN
- 2397                                               SemError(218);
- 2398                                               t := SymTab.InvalidType
- 2399                                              ELSE
- 2400                                                eT := SymTab.ArrayElem(t);
- 2401                                                t := eT; sfx := TRUE
- 2402                                              END; .) }
- 2403          "]"
- 2404        | "." GetIdent<fn>
- 2405                                          (. astSel := AST.MakeNode(AST.NkSelector);
- 2406               AST.SetOp(astSel, AST.SelField);
- 2407               AST.SetChild(astSel, 0, AST.MakeLeaf(AST.NkIdent, fn));
- 2408               AST.SetChild(astDes, AST.NChild(astDes), astSel); IF k = SymTab.KindModule THEN
- 2409                                               (* qualified L.x: materialize
- 2410                                                  the export, then load it *)
- 2411                                               IF NOT SymTab.MaterializeAlias(n,
- 2412                                                    fn, mal) THEN
- 2413                                                 SemError(201);
- 2414                                                 t := SymTab.InvalidType;
- 2415                                                 QbeGen.CopyOp("0", q)
- 2416                                               ELSE
- 2417                                                 QbeGen.CopyOp(mal, qn);
- 2418                                                 t := SymTab.SymType(mal);
- 2419                                                 k := SymTab.SymKind(mal);
- 2420                                                 sfx := FALSE;
- 2421                                                 IF k = SymTab.KindProc THEN
- 2422                                                   (* call: ArgList supplies
- 2423                                                      the value *)
- 2424                                                   QbeGen.CopyOp("0", q)
- 2425                                                  END
- 2426                                               END
- 2427                                             ELSIF t = SymTab.InvalidType THEN
- 2428                                             ELSIF (SymTab.ClassOf(t) #
- 2429                                                    SymTab.ClRecord)
- 2430   AND (SymTab.ClassOf(t) #
- 2431                                                   SymTab.ClClass) THEN
- 2432                                               SemError(215);
+ 1635                                               sfx, isInc: BOOLEAN;
+ 1636                                               astNode, astD, astStep:
+ 1637                                                 AST.Node; .)
+ 1638      =                                   (. isInc := TRUE; .)
+ 1639        ( "INC"                           (. isInc := TRUE; .)
+ 1640        | "DEC"                           (. isInc := FALSE; .) )
+ 1641        "("                               (. astStep := AST.NoNode; .)
+ 1642        Design<dt, dk, qd, qn, sfx> (. astD := astCur; .)
+ 1643        [ "," Expr<et2, qstep> (. astStep := astCur; .) ]
+ 1644        ")"                               (. astNode := AST.MakeNode(AST.NkCall);
+ 1645                                             IF isInc THEN
+ 1646                                               AST.SetChild(astNode, 0,
+ 1647                                                 AST.MakeLeaf(AST.NkIdent, "INC"))
+ 1648                                             ELSE AST.SetChild(astNode, 0,
+ 1649                                                 AST.MakeLeaf(AST.NkIdent, "DEC"))
+ 1650                                             END;
+ 1651                                             IF astD # AST.NoNode THEN
+ 1652                                               AST.SetChild(astNode, 1, astD) END;
+ 1653                                             IF astStep # AST.NoNode THEN
+ 1654                                               AST.SetChild(astNode, 2, astStep) END;
+ 1655                                             astStmt := astNode; .)                               (. IF dt = SymTab.InvalidType THEN
+ 1656                                             ELSIF (dk # SymTab.KindVar)
+ 1657   AND (dk # SymTab.KindParam)
+ 1658   AND (dk # SymTab.KindField) THEN
+ 1659                                               SemError(210)
+ 1660                                             ELSIF NOT SymTab.IsIntFamily(dt) THEN
+ 1661                                               SemError(211)
+ 1662                                             END; .) .
+ 1663    (* NEW/DISPOSE as builtin statements (no call syntax until step 4).
+ 1664       Targets are pointer designators; DISPOSE nils afterwards (safer
+ 1665       than Wirth-undefined; documented). DISPOSE is shallow. *)
+ 1666    NewStat                               (. VAR dt: SymTab.TypeIndex;
+ 1667                                               dk: INTEGER;
+ 1668                                               qd, qm: QbeGen.QVal;
+ 1669                                               qn: SymTab.Name;
+ 1670                                               sfx: BOOLEAN;
+ 1671                                               bt: SymTab.TypeIndex;
+ 1672                                               astNode, astD: AST.Node; .)
+ 1673      = "NEW" "(" Design<dt, dk, qd, qn, sfx> (. astD := astCur; .) ")"
+ 1674                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 1675                                             AST.SetChild(astNode, 0,
+ 1676                                               AST.MakeLeaf(AST.NkIdent, "NEW"));
+ 1677                                             IF astD # AST.NoNode THEN
+ 1678                                               AST.SetChild(astNode, 1, astD) END;
+ 1679                                             astStmt := astNode; .)
+ 1680                                           (. IF dt = SymTab.InvalidType THEN
+ 1681                                              ELSIF (dk # SymTab.KindVar)
+ 1682    AND (dk # SymTab.KindParam)
+ 1683    AND (dk # SymTab.KindField) THEN
+ 1684                                                SemError(210)
+ 1685                                              ELSIF SymTab.ClassOf(dt) #
+ 1686                                                    SymTab.ClPtr THEN
+ 1687                                                SemError(219)
+ 1688                                              END; .) .
+ 1689    DisposeStat                           (. VAR dt: SymTab.TypeIndex;
+ 1690                                               dk: INTEGER;
+ 1691                                               qd, qv: QbeGen.QVal;
+ 1692                                               qn: SymTab.Name;
+ 1693                                               sfx: BOOLEAN;
+ 1694                                               astNode, astD: AST.Node; .)
+ 1695      = "DISPOSE" "(" Design<dt, dk, qd, qn, sfx> (. astD := astCur; .) ")"
+ 1696                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 1697                                             AST.SetChild(astNode, 0,
+ 1698                                               AST.MakeLeaf(AST.NkIdent, "DISPOSE"));
+ 1699                                             IF astD # AST.NoNode THEN
+ 1700                                               AST.SetChild(astNode, 1, astD) END;
+ 1701                                             astStmt := astNode; .)
+ 1702                                           (. IF dt = SymTab.InvalidType THEN
+ 1703                                              ELSIF (dk # SymTab.KindVar)
+ 1704    AND (dk # SymTab.KindParam)
+ 1705    AND (dk # SymTab.KindField) THEN
+ 1706                                                SemError(210)
+ 1707                                              ELSIF SymTab.ClassOf(dt) #
+ 1708                                                    SymTab.ClPtr THEN
+ 1709                                                SemError(219)
+ 1710                                              END; .) .
+ 1711    (* WITH pushes each record's fields (inner wins) plus its base
+ 1712       address; field designators resolve through both stacks. *)
+ 1713    WithStat                              (. VAR nW: CARDINAL;
+ 1714                                               astNode: AST.Node; .)
+ 1715      = "WITH"                            (. nW := 0;
+ 1716                                             astNode := AST.MakeNode(AST.NkWith); .)
+ 1717        WithItem<nW, astNode> { "," WithItem<nW, astNode> }
+ 1718        "DO"                              (. astStmt := AST.NoNode; .)
+ 1719        [ StatSeq ] "END"                 (. AST.SetChild(astNode,
+ 1720                                             AST.NChild(astNode), astStmt);
+ 1721                                             astStmt := astNode;
+ 1722                                             WHILE nW > 0 DO
+ 1723                                               SymTab.PopScope;
+ 1724                                               QbeGen.PopWith;
+ 1725                                               DEC(nW)
+ 1726                                             END; .) .
+ 1727    WithItem<VAR nW: CARDINAL; wnode: AST.Node>
+ 1728                                          (. VAR dt: SymTab.TypeIndex;
+ 1729                                               dk: INTEGER;
+ 1730                                               qd, qe: QbeGen.QVal;
+ 1731                                               qn: SymTab.Name;
+ 1732                                               sfx: BOOLEAN; .)
+ 1733      = Design<dt, dk, qd, qn, sfx>
+ 1734                                          (. IF astCur # AST.NoNode THEN
+ 1735                                               AST.SetChild(wnode,
+ 1736                                                 AST.NChild(wnode), astCur) END;
+ 1737                                             IF dt = SymTab.InvalidType THEN
+ 1738                                             ELSIF (SymTab.ClassOf(dt) #
+ 1739                                                    SymTab.ClRecord)
+ 1740   AND (SymTab.ClassOf(dt) #
+ 1741                                                   SymTab.ClClass) THEN
+ 1742                                               SemError(215)
+ 1743                                             ELSIF SymTab.PushRecord(dt) THEN
+ 1744                                               QbeGen.PushWith(qd);
+ 1745                                               INC(nW)
+ 1746                                             END; .) .
+ 1747    (* Assignment or procedure-statement call (4.1, module level).
+ 1748       Bare `P;` is a syntax error; function-as-statement is 233. *)
+ 1749    AssOrCall                             (. VAR dt, et: SymTab.TypeIndex;
+ 1750                                               dk: INTEGER;
+ 1751                                               qd, qe, qt, ql: QbeGen.QVal;
+ 1752                                               qn: SymTab.Name;
+ 1753                                               ct2, res0: SymTab.TypeIndex;
+ 1754                                               q2, mg0: QbeGen.QVal;
+ 1755                                               isR, conv, wconv: BOOLEAN;
+ 1756                                               called, sfx: BOOLEAN;
+ 1757                                               astLhs, astRes: AST.Node; mname: SymTab.Name; isM: BOOLEAN;
+ 1758                                               n: SymTab.Name; astLab, astNode: AST.Node; .)
+ 1759      = GetIdent<n>
+ 1760        ( ":"                             (. NoteLabel(n);
+ 1761                                             astNode := AST.MakeNode(AST.NkLabel);
+ 1762                                             AST.SetChild(astNode, 0,
+ 1763                                               AST.MakeLeaf(AST.NkIdent, n));
+ 1764                                             astLab := AST.MakeNode(AST.NkBlock);
+ 1765                                             AST.SetChild(astLab, 0, astNode); .)
+ 1766          Statement                       (. IF astStmt # AST.NoNode THEN
+ 1767                                               AST.SetChild(astLab, 1, astStmt) END;
+ 1768                                             astStmt := astLab; .)
+ 1769        | DesignTail<n, dt, dk, qd, qn, sfx>
+ 1770        (. astLhs := astCur; astNArgs := 0; .)
+ 1771        ( ":="
+ 1772          Expr<et, qe>                    (. astStmt := AST.MakeBin(
+ 1773                                               AST.NkAssign, 0, astLhs, astCur);
+ 1774                                             IF (dt # SymTab.InvalidType)
+ 1775   AND (dk # SymTab.KindVar)
+ 1776   AND (dk # SymTab.KindParam)
+ 1777   AND (dk # SymTab.KindField) THEN
+ 1778                                             SemError(210)
+ 1779                                           ELSIF NOT SymTab.Assignable(et,
+ 1780                                                    dt) THEN
+ 1781                                             SemError(210)
+ 1782                                           ELSIF (dt # SymTab.InvalidType)
+ 1783   AND (SymTab.ClassOf(dt) =
+ 1784                                                 SymTab.ClClass) THEN
+ 1785                                             SemError(230) END;
+ 1786                                           isR := (dt #
+ 1787                                                   SymTab.InvalidType)
+ 1788   AND (SymTab.ClassOf(dt)
+ 1789                                                     = SymTab.ClReal);
+ 1790                                           conv := isR
+ 1791   AND SymTab.IsIntFamily(et);
+ 1792                                           wconv := (dt #
+ 1793                                                     SymTab.InvalidType)
+ 1794   AND SymTab.IsLongFamily(dt)
+ 1795   AND SymTab.IsIntFamily(et);
+ 1796                                           IF ((dk = SymTab.KindVar)
+ 1797                                               OR (dk = SymTab.KindParam)
+ 1798                                               OR (dk = SymTab.KindField))
+ 1799   AND (dt # SymTab.InvalidType)
+ 1800   AND (et # SymTab.InvalidType)
+ 1801   AND (SymTab.ClassOf(dt) #
+ 1802                                                 SymTab.ClClass) THEN
+ 1803                                           END; .)
+ 1804        | ArgList<qn, dt, qd, TRUE, TRUE, methCls, ct2, q2, called>
+ 1805                                          (. astRes := AstCallNode(astLhs);
+ 1806                                             sfx := FALSE; .)
+ 1807          ( { ResultComp<ct2, q2, sfx, astRes, mname, methCls, isM> }
+ 1808            ":=" Expr<et, qe>             (. astStmt := AST.MakeBin(
+ 1809                                               AST.NkAssign, 0, astRes, astCur);
+ 1810                                             IF NOT sfx THEN
+ 1811                                               SemError(233)
+ 1812                                             ELSIF (ct2 # SymTab.InvalidType)
+ 1813    AND NOT SymTab.Assignable(et, ct2) THEN
+ 1814                                               SemError(210)
+ 1815                                             END; .)
+ 1816          |                               (. IF ct2 #
+ 1817                                               SymTab.InvalidType THEN
+ 1818                                               SemError(233) END;
+ 1819                                             astStmt := astRes; .) )
+ 1820        |                                 (* bare `P;`: proper parameterless
+ 1821                                              procedure call; anything else
+ 1822                                              here is 233 (was a bare syntax
+ 1823                                              error before 4.2) *)
+ 1824                                          (. astStmt := AstCallNode(astLhs);
+ 1825                                              IF (dk = SymTab.KindProc)
+ 1826   AND NOT sfx THEN
+ 1827                                               res0 := SymTab.ProcRes(qn);
+ 1828                                               IF res0 #
+ 1829                                                  SymTab.InvalidType THEN
+ 1830                                                 SemError(233)
+ 1831                                               ELSIF SymTab.ProcNPar(qn) #
+ 1832                                                       0 THEN
+ 1833                                                 SemError(233)
+ 1834                                               END
+ 1835                                             ELSE SemError(233)
+ 1836                                              END; .) ) ) .
+ 1837    (* Actual-parameter list shared by statement and expression calls.
+ 1838       want selects CallEnd's result handling; t/q carry the call
+ 1839       value (statement calls discard). Arity/type failures are 233;
+ 1840       evaluation code still emits so the .ssa stays assembleable. *)
+ 1841    ArgList<pn: SymTab.Name; pt: SymTab.TypeIndex; callee: QbeGen.QVal;
+ 1842            want: BOOLEAN; soft: BOOLEAN; methCls: SymTab.TypeIndex;
+ 1843            VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal;
+ 1844            VAR called: BOOLEAN>          (. VAR i, np: CARDINAL;
+ 1845                                               vs: INTEGER;
+ 1846                                               res: SymTab.TypeIndex;
+ 1847                                               mg: QbeGen.QVal;
+ 1848                                               ok, ind, isMeth, va: BOOLEAN; .)
+ 1849      = "("                               (. called := TRUE;
+ 1850                                             ok := TRUE;
+ 1851                                             ind := FALSE;
+ 1852                                             isMeth := methCls #
+ 1853                                               SymTab.InvalidType;
+ 1854                                             IF isMeth THEN
+ 1855                                               res := SymTab.ClassMethodRes(methCls, pn)
+ 1856                                             ELSIF SymTab.SymKind(pn) = SymTab.KindProc THEN
+ 1857                                               res := SymTab.ProcRes(pn)
+ 1858                                             ELSIF (pt # SymTab.InvalidType)
+ 1859    AND (SymTab.ClassOf(pt) = SymTab.ClProc) THEN
+ 1860                                               ind := TRUE;
+ 1861                                               res := SymTab.ProcTypeRes(pt)
+ 1862                                             ELSE SemError(233);
+ 1863                                               ok := FALSE;
+ 1864                                               res := SymTab.InvalidType
+ 1865                                             END;
+ 1866                                             i := 0; .)
+ 1867        [ ActParam<pn, pt, ind, methCls, i>        (. INC(i); .)
+ 1868          { "," ActParam<pn, pt, ind, methCls, i>  (. INC(i); .) } ]
+ 1869        ")"                               (. IF ok THEN
+ 1870                                               IF isMeth THEN
+ 1871                                                 np := SymTab.ClassMethodNPar(
+ 1872                                                   methCls, pn)
+ 1873                                               ELSIF ind THEN
+ 1874                                                 np := SymTab.ProcTypeNPar(pt)
+ 1875                                               ELSE np := SymTab.ProcNPar(pn)
+ 1876                                               END;
+ 1877                                               va := (NOT isMeth) AND (NOT ind)
+ 1878                                                 AND (SymTab.SymKind(pn) =
+ 1879                                                      SymTab.KindProc)
+ 1880                                                 AND SymTab.Varargs(pn);
+ 1881                                               IF (i # np) AND NOT va THEN
+ 1882                                                 SemError(233); ok := FALSE
+ 1883                                               END
+ 1884                                             END;
+ 1885                                             IF NOT ok THEN
+ 1886                                               t := SymTab.InvalidType;
+ 1887                                               QbeGen.CopyOp("0", q)
+ 1888                                             ELSIF want THEN
+ 1889                                               IF res =
+ 1890                                                  SymTab.InvalidType THEN
+ 1891                                                 IF NOT soft THEN SemError(233) END;
+ 1892                                                 t := SymTab.InvalidType;
+ 1893                                                 QbeGen.CopyOp("0", q)
+ 1894                                               ELSE t := res;
+ 1895                                                  QbeGen.CopyOp("@", q)
+ 1896                                               END
+ 1897                                             ELSE
+ 1898                                               IF res #
+ 1899                                                  SymTab.InvalidType THEN
+ 1900                                                 SemError(233)
+ 1901                                               END;
+ 1902                                               t := SymTab.InvalidType;
+ 1903                                               QbeGen.CopyOp("0", q);
+ 1904                                             END; .) .
+ 1905    (* One actual: VAR formals take recorded designator addresses
+ 1906       (233 otherwise); value formals take converted expressions. *)
+ 1907    ActParam<pn: SymTab.Name; pt: SymTab.TypeIndex; ind: BOOLEAN;
+ 1908             methCls: SymTab.TypeIndex; i: CARDINAL>
+ 1909                                          (. VAR at, ft: SymTab.TypeIndex;
+ 1910                                               qe, qa, qt: QbeGen.QVal;
+ 1911                                               isV, conv, va: BOOLEAN;
+ 1912                                               cl: CHAR;
+ 1913                                               savedN, aj: CARDINAL;
+ 1914                                               savedArgs: ARRAY [0 .. 31]
+ 1915                                                 OF AST.Node;
+ 1916                                               astActual: AST.Node; .)
+ 1917      =                                   (. (* Parsing the actual can clobber
+ 1918                                               the enclosing call's argument
+ 1919                                               list (Factor resets astNArgs),
+ 1920                                               so save/restore it. *)
+ 1921                                             savedN := astNArgs; aj := 0;
+ 1922                                             WHILE aj <= HIGH(astArgs) DO
+ 1923                                               savedArgs[aj] := astArgs[aj];
+ 1924                                               INC(aj)
+ 1925                                             END; .)
+ 1926        Expr<at, qe>                      (. astActual := astCur;
+ 1927                                             astNArgs := savedN; aj := 0;
+ 1928                                             WHILE aj <= HIGH(astArgs) DO
+ 1929                                               astArgs[aj] := savedArgs[aj];
+ 1930                                               INC(aj)
+ 1931                                             END;
+ 1932                                             IF astNArgs <= HIGH(astArgs) THEN
+ 1933                                               astArgs[astNArgs] := astCur;
+ 1934                                               INC(astNArgs)
+ 1935                                             END;
+ 1936                                             va := (NOT ind)
+ 1937                                               AND (methCls =
+ 1938                                                  SymTab.InvalidType)
+ 1939                                               AND (SymTab.SymKind(pn) =
+ 1940                                                  SymTab.KindProc)
+ 1941                                               AND SymTab.Varargs(pn);
+ 1942                                             IF ind THEN
+ 1943                                               ft :=
+ 1944                                                 SymTab.ProcTypeParamType(pt,
+ 1945                                                   i);
+ 1946                                               isV :=
+ 1947                                                 SymTab.ProcTypeParamIsVar(pt,
+ 1948                                                   i)
+ 1949                                             ELSIF methCls #
+ 1950                                                SymTab.InvalidType THEN
+ 1951                                               ft :=
+ 1952                                                 SymTab.ClassMethodParamType(
+ 1953                                                 methCls, pn, i);
+ 1954                                               isV :=
+ 1955                                                 SymTab.ClassMethodParamIsVar(
+ 1956                                                 methCls, pn, i)
+ 1957                                             ELSE
+ 1958                                               ft := SymTab.ParamType(pn, i);
+ 1959                                               isV := SymTab.ParamIsVar(pn, i)
+ 1960                                             END;
+ 1961                                             IF (at = SymTab.InvalidType) THEN
+ 1962                                             ELSIF ft = SymTab.InvalidType THEN
+ 1963                                             ELSIF isV THEN
+ 1964                                               IF (SymTab.ClassOf(at) = SymTab.ClChar)
+ 1965    AND (SymTab.ClassOf(ft) = SymTab.ClArray)
+ 1966    AND (SymTab.ClassOf(SymTab.ArrayElem(ft)) = SymTab.ClChar)
+ 1967    AND QbeGen.IsImm(qe) THEN
+ 1968                                               ELSIF (AST.Kind(astActual) #
+ 1969                                                      AST.NkDesignator)
+ 1970    AND (AST.Kind(astActual) # AST.NkStrLit) THEN
+ 1971                                                 SemError(233)
+ 1972                                               ELSIF NOT SymTab.VarParamOk(at, ft) THEN
+ 1973                                                 SemError(233)
+ 1974                                               END
+ 1975                                             ELSE
+ 1976                                               IF (SymTab.ClassOf(at) = SymTab.ClChar)
+ 1977    AND (SymTab.ClassOf(ft) = SymTab.ClArray)
+ 1978    AND (SymTab.ClassOf(SymTab.ArrayElem(ft)) = SymTab.ClChar)
+ 1979    AND QbeGen.IsImm(qe) THEN
+ 1980                                               ELSIF NOT SymTab.Assignable(at, ft) THEN
+ 1981                                                 SemError(233)
+ 1982                                               END
+ 1983                                             END; .) .
+ 1984    IfStat                                (. VAR t: SymTab.TypeIndex;
+ 1985                                               q: QbeGen.QVal;
+ 1986                                               hasElse: BOOLEAN;
+ 1987                                               astCond, astIf, astLast,
+ 1988                                               astNode: AST.Node; .)
+ 1989      = "IF" (. hasElse := FALSE; .)
+ 1990        Expr<t, q> (. astCond := astCur; astStmt := AST.NoNode;
+ 1991                                             IF NOT SymTab.BoolCheck(t) THEN
+ 1992                                               SemError(214) END; .)
+ 1993        "THEN" [ StatSeq ]                (. astNode := AST.MakeNode(AST.NkIf);
+ 1994                                             AST.SetChild(astNode, 0, astCond);
+ 1995                                             AST.SetChild(astNode, 1, astStmt);
+ 1996                                             astIf := astNode;
+ 1997                                             astLast := astNode; .)
+ 1998        { "ELSIF"
+ 1999          Expr<t, q> (. astCond := astCur; astStmt := AST.NoNode;
+ 2000                                             IF NOT SymTab.BoolCheck(t) THEN
+ 2001                                               SemError(214) END; .)
+ 2002          "THEN" [ StatSeq ]              (. astNode := AST.MakeNode(AST.NkIf);
+ 2003                                             AST.SetChild(astNode, 0, astCond);
+ 2004                                             AST.SetChild(astNode, 1, astStmt);
+ 2005                                             AST.SetChild(astLast, 2, astNode);
+ 2006                                             astLast := astNode; .) }
+ 2007        [ "ELSE"                          (. hasElse := TRUE;
+ 2008                                             astStmt := AST.NoNode; .)
+ 2009          [ StatSeq ] (. AST.SetChild(astLast, 2, astStmt); .) ]
+ 2010        "END" (. astStmt := astIf; .) .
+ 2011    WhileStat                             (. VAR t: SymTab.TypeIndex;
+ 2012                                               q: QbeGen.QVal;
+ 2013                                               astCond, astNode: AST.Node; .)
+ 2014      = "WHILE" (. astStmt := AST.NoNode; .)
+ 2015        Expr<t, q> (. astCond := astCur;
+ 2016                                             IF NOT SymTab.BoolCheck(t) THEN
+ 2017                                               SemError(214) END; .)
+ 2018        "DO" [ StatSeq ]                  (. astNode := AST.MakeNode(AST.NkWhile);
+ 2019                                             AST.SetChild(astNode, 0, astCond);
+ 2020                                             AST.SetChild(astNode, 1, astStmt);
+ 2021                                             astStmt := astNode; .)
+ 2022        "END" .
+ 2023    RepeatStat                            (. VAR t: SymTab.TypeIndex;
+ 2024                                               q: QbeGen.QVal;
+ 2025                                               astCond, astBody, astNode:
+ 2026                                                 AST.Node; .)
+ 2027      = "REPEAT" (. astStmt := AST.NoNode; .)
+ 2028        [ StatSeq ] (. astBody := astStmt; .)
+ 2029        "UNTIL" Expr<t, q> (. astCond := astCur;
+ 2030                                             astNode := AST.MakeNode(AST.NkRepeat);
+ 2031                                             AST.SetChild(astNode, 0, astBody);
+ 2032                                             AST.SetChild(astNode, 1, astCond);
+ 2033                                             astStmt := astNode;
+ 2034                                             IF NOT SymTab.BoolCheck(t) THEN
+ 2035                                               SemError(214) END; .) .
+ 2036    LoopStat                              (. VAR lEnd: QbeGen.QVal; astNode: AST.Node; .)
+ 2037      = "LOOP"                            (. astStmt := AST.NoNode;
+ 2038                                             QbeGen.NewLabel(lEnd);
+ 2039                                             QbeGen.PushLoop(lEnd); .)
+ 2040        [ StatSeq ]
+ 2041        "END"                             (. astNode := AST.MakeNode(AST.NkLoop);
+ 2042                                             AST.SetChild(astNode, 0, astStmt);
+ 2043                                             astStmt := astNode;
+ 2044                                             QbeGen.PopLoop; .) .
+ 2045    (* FOR with static-sign BY (literal, non-zero; 220 otherwise).
+ 2046       Runtime direction would need a compare-select; the literal
+ 2047       sign picks cslew/csegew at "DO" time. *)
+ 2048    ForStat                               (. VAR lv: SymTab.Name;
+ 2049                                               tlo, thi, tby:
+ 2050                                                 SymTab.TypeIndex;
+ 2051                                               qlo, qhi, qby, qt, qk, qb:
+ 2052                                                 QbeGen.QVal;
+ 2053                                               lTop, lBody, lEnd:
+ 2054                                                 QbeGen.QVal;
+ 2055                                               by: INTEGER;
+ 2056                                               ok: BOOLEAN;
+ 2057                                               astVar, astLo, astHi, astBy,
+ 2058                                               astNode: AST.Node; .)
+ 2059      = "FOR"                             (. by := 1; .)
+ 2060        GetIdent<lv> (. astVar := AST.MakeLeaf(AST.NkIdent, lv);
+ 2061                                             astStmt := AST.NoNode;
+ 2062                                             astBy := AST.NoNode;
+ 2063                                             ok := SymTab.Lookup(lv);
+ 2064                                             IF NOT ok THEN
+ 2065                                               SemError(201)
+ 2066                                             ELSIF (SymTab.SymKind(lv) #
+ 2067                                                    SymTab.KindVar)
+ 2068   AND (SymTab.SymKind(lv) #
+ 2069                                                   SymTab.KindParam) THEN
+ 2070                                               SemError(220); ok := FALSE
+ 2071                                             ELSIF NOT SymTab.IsIntFamily(
+ 2072                                                     SymTab.SymType(lv)) THEN
+ 2073                                               SemError(220); ok := FALSE
+ 2074                                             END; .)
+ 2075        ":=" Expr<tlo, qlo> (. astLo := astCur;
+ 2076                                             IF NOT SymTab.IsIntFamily(tlo) THEN
+ 2077                                               SemError(220); ok := FALSE
+ 2078                                             END; .)
+ 2079        "TO" Expr<thi, qhi> (. astHi := astCur;
+ 2080                                             IF NOT SymTab.IsIntFamily(thi) THEN
+ 2081                                               SemError(220); ok := FALSE
+ 2082                                             END; .)
+ 2083        [ "BY" Expr<tby, qby> (. astBy := astCur;
+ 2084                                             IF (tby #
+ 2085                                               SymTab.InvalidType)
+ 2086   AND NOT SymTab.IsIntFamily(tby) THEN
+ 2087                                               SemError(220); ok := FALSE
+ 2088                                             END;
+ 2089                                             IF NOT SymTab.ConstInt(qby, by) THEN
+ 2090                                               SemError(230); by := 1
+ 2091                                             ELSIF by = 0 THEN
+ 2092                                               SemError(220); by := 1
+ 2093                                             END; .) ]
+ 2094        "DO"
+ 2095        [ StatSeq ]
+ 2096        "END" (. astNode := AST.MakeNode(AST.NkFor);
+ 2097                                             AST.SetChild(astNode, 0, astVar);
+ 2098                                             AST.SetChild(astNode, 1, astLo);
+ 2099                                             AST.SetChild(astNode, 2, astHi);
+ 2100                                             AST.SetChild(astNode, 3, astBy);
+ 2101                                             AST.SetChild(astNode, 4, astStmt);
+ 2102                                             astStmt := astNode;
+ 2103                                             .) .
+ 2104    CaseStat                              (. VAR tsel: SymTab.TypeIndex;
+ 2105                                               qsel, lEnd: QbeGen.QVal;
+ 2106                                               arm, astNode, astArms,
+ 2107                                               astArmsTail: AST.Node; .)
+ 2108      = "CASE" Expr<tsel, qsel>           (. astNode := AST.MakeNode(AST.NkCase);
+ 2109                                             AST.SetChild(astNode, 0, astCur);
+ 2110                                             astArms := AST.NoNode;
+ 2111                                             astArmsTail := AST.NoNode;
+ 2112                                             .)
+ 2113        "OF" CaseAlt<tsel, qsel, lEnd, astArms, astArmsTail>
+ 2114        { "|" CaseAlt<tsel, qsel, lEnd, astArms, astArmsTail> }
+ 2115        [ "ELSE"                          (. astStmt := AST.NoNode; .)
+ 2116          [ StatSeq ]                     (. arm := AST.MakeNode(AST.NkCaseArm);
+ 2117                                             AST.SetOp(arm, 1);
+ 2118                                             AST.SetChild(arm, 0, astStmt);
+ 2119                                             AstAppend(AST.NkBlock,
+ 2120                                               astArms, astArmsTail, arm); .) ]
+ 2121        "END"                             (. AST.SetChild(astNode, 1, astArms);
+ 2122                                             astStmt := astNode;
+ 2123                                             .) .
+ 2124    (* Compare-chain lowering: each alternative ends its match-tests
+ 2125       with "jmp lAfter", so the no-match fallthrough skips the body:
+ 2126       "cmp; jnz(lBody,lF); lF: ... ; jmp lAfter; lBody: S; jmp lEnd;
+ 2127       lAfter:". Falls into the next alternative, ELSE, or END. *)
+ 2128    CaseAlt<tsel: SymTab.TypeIndex; qsel: QbeGen.QVal;
+ 2129            lEnd: QbeGen.QVal; VAR arms, armsTail: AST.Node>
+ 2130                                          (. VAR arm: AST.Node; .)
+ 2131      =                                   (. arm := AST.MakeNode(AST.NkCaseArm); .)
+ 2132        CaseLabel<tsel, qsel, arm>
+ 2133        { "," CaseLabel<tsel, qsel, arm> }
+ 2134        ":"                               (. astStmt := AST.NoNode; .)
+ 2135        [ StatSeq ]                       (. AST.SetChild(arm, AST.NChild(arm),
+ 2136                                             astStmt);
+ 2137                                             AstAppend(AST.NkBlock,
+ 2138                                               arms, armsTail, arm);
+ 2139                                             .) .
+ 2140    CaseLabel<tsel: SymTab.TypeIndex; qsel: QbeGen.QVal;
+ 2141              arm: AST.Node>
+ 2142                                          (. VAR t2, t3: SymTab.TypeIndex;
+ 2143                                               q2, q3, qc, qd, qe:
+ 2144                                                 QbeGen.QVal;
+ 2145                                               astLab: AST.Node;
+ 2146                                               lNext: QbeGen.QVal; .)
+ 2147      = Expr<t2, q2> (. astLab := astCur;
+ 2148                                             IF (t2 #
+ 2149                                               SymTab.InvalidType)
+ 2150   AND (tsel #
+ 2151                                                 SymTab.InvalidType)
+ 2152   AND ((SymTab.ClassOf(t2) =
+ 2153                                                  SymTab.ClSet)
+ 2154                                                 OR (SymTab.ClassOf(tsel) =
+ 2155                                                     SymTab.ClSet)) THEN
+ 2156                                               SemError(230)
+ 2157                                             ELSIF (t2 #
+ 2158                                               SymTab.InvalidType)
+ 2159   AND (tsel #
+ 2160                                                 SymTab.InvalidType)
+ 2161   AND NOT SymTab.EqCheck(t2,
+ 2162                                                   tsel) THEN
+ 2163                                               SemError(213) END;
+ 2164                                                 IF NOT QbeGen.IsImm(q2) THEN
+ 2165                                                   SemError(230)
+ 2166                                                 END; .)
+ 2167        [ ".." Expr<t3, q3>               (. astLab := AST.MakeBin(
+ 2168                                               AST.NkSubrange, 0, astLab, astCur);
+ 2169                                             IF (t3 #
+ 2170                                               SymTab.InvalidType)
+ 2171   AND (tsel #
+ 2172                                                 SymTab.InvalidType)
+ 2173   AND NOT SymTab.EqCheck(t3,
+ 2174                                                   tsel) THEN
+ 2175                                               SemError(213) END;
+ 2176                                                 IF NOT QbeGen.IsImm(q3) THEN
+ 2177                                                   SemError(230)
+ 2178                                                 END; .) ]
+ 2179                                          (. AST.SetChild(arm,
+ 2180                                               AST.NChild(arm), astLab); .) .
+ 2181    ReturnStat                            (. VAR t: SymTab.TypeIndex;
+ 2182                                               q, qt: QbeGen.QVal;
+ 2183                                               res: SymTab.TypeIndex;
+ 2184                                               hadE, conv: BOOLEAN;
+ 2185                                               astVal, astNode: AST.Node; .)
+ 2186      = "RETURN"                          (. hadE := FALSE; astStmt := AST.NoNode; .)
+ 2187        [ Expr<t, q> (. hadE := TRUE; astVal := astCur; .) ]
+ 2188                                          (. astNode := AST.MakeNode(AST.NkReturn);
+ 2189                                             IF hadE THEN
+ 2190                                               AST.SetChild(astNode, 0, astVal)
+ 2191                                             END;
+ 2192                                             astStmt := astNode;
+ 2193                                             conv := FALSE;
+ 2194                                             IF NOT SymTab.InProc() THEN
+ 2195                                               SemError(232)
+ 2196                                             ELSE res := SymTab.CurRes();
+ 2197                                               IF NOT hadE THEN
+ 2198                                                 IF res #
+ 2199                                                    SymTab.InvalidType THEN
+ 2200                                                   SemError(232)
+ 2201                                                 END
+ 2202                                               ELSIF (res =
+ 2203                                                      SymTab.InvalidType)
+ 2204                                                  OR (t #
+ 2205                                                      SymTab.InvalidType)
+ 2206   AND NOT SymTab.Assignable(t,
+ 2207                                                       res) THEN
+ 2208                                                 SemError(232)
+ 2209                                             END
+ 2210                                             END; .) .
+ 2211    HaltStat                              (. VAR t: SymTab.TypeIndex;
+ 2212                                               q: QbeGen.QVal;
+ 2213                                               astVal, astNode: AST.Node; .)
+ 2214      = "HALT" (. astVal := AST.NoNode; .)
+ 2215        [ "(" Expr<t, q> (. astVal := astCur; .) ")" ]
+ 2216                                          (. astNode := AST.MakeNode(AST.NkHalt);
+ 2217                                             IF astVal # AST.NoNode THEN
+ 2218                                               AST.SetChild(astNode, 0, astVal)
+ 2219                                             END;
+ 2220                                             astStmt := astNode;
+ 2221                                             .) .
+ 2222    (* Designator: scalar loads, array addresses, and index suffixes.
+ 2223       Each index descends one level (bounds-checked, trap on breach);
+ 2224       nested levels reload the inner descriptor address. q ends as the
+ 2225       value (scalars), the descriptor address (plain arrays), or the
+ 2226       element address (indexed); sfx marks the indexed form. *)
+ 2227    Design<VAR t: SymTab.TypeIndex; VAR k: INTEGER;
+ 2228           VAR q: QbeGen.QVal; VAR qn: SymTab.Name; VAR sfx: BOOLEAN>
+ 2229                                          (. VAR n: SymTab.Name; .)
+ 2230      = GetIdent<n> DesignTail<n, t, k, q, qn, sfx> .
+ 2231    (* The part of Design after the identifier: resolve it and walk the
+ 2232       selectors.  Split out so a statement can decide between a label
+ 2233       (`ident :`) and a designator (`ident := ...`) with one token. *)
+ 2234    DesignTail<VAR n: SymTab.Name; VAR t: SymTab.TypeIndex; VAR k: INTEGER;
+ 2235           VAR q: QbeGen.QVal; VAR qn: SymTab.Name; VAR sfx: BOOLEAN>
+ 2236                                          (. VAR fn, mal: SymTab.Name;
+ 2237                                               cls: INTEGER;
+ 2238                                               ic: SymTab.TypeIndex;
+ 2239                                               curT, it, eT, bt:
+ 2240                                                 SymTab.TypeIndex;
+ 2241                                               iq, ql, qlo, qhi, qe:
+ 2242                                                 QbeGen.QVal;
+ 2243                                               lo, hi: INTEGER;
+ 2244                                               fo: INTEGER;
+ 2245                                               isOpen: BOOLEAN;
+ 2246                                               qb, cv: QbeGen.QVal;
+ 2247                                               fid, fref: INTEGER;
+ 2248                                               r: BOOLEAN;
+ 2249                                                astDes, astSel: AST.Node;
+ 2250                                               fwd: BOOLEAN; .)
+ 2251      =                                   (. methCls := SymTab.InvalidType;
+ 2252                                             QbeGen.CopyOp(n, qn);
+ 2253                                             sfx := FALSE; fwd := FALSE;
+ 2254                                             fid := 0; fref := 0;
+ 2255                                             IF NOT SymTab.Lookup(n) THEN
+ 2256                                               (* a bare method name inside
+ 2257                                                  a CLASS IMPLEMENTATION
+ 2258                                                  is a sibling call on
+ 2259                                                  THIS *)
+ 2260                                               ic := SymTab.CurImplClass();
+ 2261                                               IF (ic #
+ 2262                                                  SymTab.InvalidType)
+ 2263    AND SymTab.MethodExists(ic, n) THEN
+ 2264                                                 sfx := FALSE;
+ 2265                                                  QbeGen.CopyOp("@", q);
+ 2266                                                 methCls := ic;
+ 2267                                                 k := SymTab.KindProc;
+ 2268                                                 t := SymTab.InvalidType
+ 2269                                               ELSIF SymTab.InProc() THEN
+ 2270                                                 (* not declared yet: a
+ 2271                                                    forward reference to a
+ 2272                                                    module-level variable
+ 2273                                                    declared further down. *)
+ 2274                                                 k := SymTab.KindVar;
+ 2275                                                 r := SymTab.FwdVarRef(n, k,
+ 2276                                                   fref, t);
+ 2277                                                  QbeGen.CopyOp("@", q);
+ 2278                                                 sfx := TRUE; fwd := TRUE
+ 2279                                               ELSE
+ 2280                                                 SemError(201);
+ 2281                                                 t :=
+ 2282                                                   SymTab.InvalidType;
+ 2283                                                 k := -1;
+ 2284                                                 QbeGen.CopyOp("0", q)
+ 2285                                               END
+ 2286                                             ELSE
+ 2287                                               t := SymTab.SymType(n);
+ 2288                                               k := SymTab.SymKind(n);
+ 2289                                               IF k = SymTab.KindConst THEN
+ 2290                                                 IF SymTab.Equal(n,
+ 2291                                                    "TRUE") THEN
+ 2292                                                   t := SymTab.BoolType();
+ 2293                                                   QbeGen.CopyOp("1", q)
+ 2294                                                 ELSIF SymTab.Equal(n,
+ 2295                                                    "FALSE") THEN
+ 2296                                                   t := SymTab.BoolType();
+ 2297                                                   QbeGen.CopyOp("0", q)
+ 2298                                                 ELSIF SymTab.Equal(n,
+ 2299                                                    "NIL") THEN
+ 2300                                                   QbeGen.CopyOp("0", q)
+ 2301                                                 ELSE
+ 2302                                                   cls :=
+ 2303                                                     SymTab.ClassOf(t);
+ 2304                                                   IF (t #
+ 2305                                                       SymTab.InvalidType)
+ 2306   AND ((cls = SymTab.ClInt)
+ 2307                                                      OR (cls
+ 2308                                                          = SymTab.ClChar)
+ 2309                                                      OR (cls
+ 2310                                                          = SymTab.ClEnum)
+ 2311                                                      OR (cls
+ 2312                                                          = SymTab.ClReal)
+ 2313                                                      OR (cls
+ 2314                                                          = SymTab.ClLong)
+ 2315                                                      OR (cls
+ 2316                                                          = SymTab.ClNil)) THEN
+ 2317                                                     IF cls = SymTab.ClNil THEN
+ 2318                                                       QbeGen.CopyOp("0", q)
+ 2319                                                     ELSIF ((cls
+ 2320                                                         = SymTab.ClInt)
+ 2321                                                       OR (cls
+ 2322                                                         = SymTab.ClChar)
+ 2323                                                       OR (cls
+ 2324                                                         = SymTab.ClEnum)
+ 2325                                                       OR (cls
+ 2326                                                         = SymTab.ClLong))
+ 2327    AND SymTab.GetSymVal(n, cv)
+ 2328    AND QbeGen.IsImm(cv) THEN
+ 2329                                                       QbeGen.CopyOp(cv, q)
+ 2330                                                     ELSE
+ 2331                                                       QbeGen.LoadVar(n,
+ 2332                                                         cls = SymTab.ClReal,
+ 2333                                                         q)
+ 2334                                                     END
+ 2335                                                   ELSIF (cls = SymTab.ClArray)
+ 2336                                                      OR (cls = SymTab.ClRecord)
+ 2337                                                      OR (cls = SymTab.ClClass)
+ 2338                                                      OR (cls = SymTab.ClStr)
+ 2339                                                      OR (cls = SymTab.ClUStr) THEN
+ 2340                                                     (* aggregate constant:
+ 2341                                                        its value IS the
+ 2342                                                        descriptor address *)
+ 2343                                                     IF SymTab.GetSymVal(n, cv) THEN
+ 2344                                                       QbeGen.CopyOp(cv, q)
+ 2345                                                     ELSE
+ 2346                                                       QbeGen.CopyOp("0", q)
+ 2347                                                     END
+ 2348                                                   ELSE
+ 2349                                                     IF t #
+ 2350                                                        SymTab.InvalidType THEN
+ 2351                                                       SemError(230)
+ 2352                                                     END;
+ 2353                                                     QbeGen.CopyOp("0", q)
+ 2354                                                   END
+ 2355                                                 END
+ 2356                                               ELSIF (k = SymTab.KindVar)
+ 2357                                                  OR (k = SymTab.KindParam) THEN
+ 2358                                                 cls := SymTab.ClassOf(t);
+ 2359                                                 IF (cls # SymTab.ClInt)
+ 2360                                                    AND (cls # SymTab.ClBool)
+ 2361                                                    AND (cls # SymTab.ClChar)
+ 2362                                                    AND (cls # SymTab.ClUChar)
+ 2363                                                    AND (cls # SymTab.ClEnum)
+ 2364                                                    AND (cls # SymTab.ClReal)
+ 2365                                                    AND (cls # SymTab.ClPtr)
+ 2366                                                    AND (cls # SymTab.ClProc)
+ 2367                                                    AND (cls # SymTab.ClLong)
+ 2368                                                    AND (cls # SymTab.ClArray)
+ 2369                                                    AND (cls # SymTab.ClSet)
+ 2370                                                    AND (cls # SymTab.ClRecord)
+ 2371                                                    AND (cls # SymTab.ClUStr)
+ 2372                                                    AND (cls # SymTab.ClClass) THEN
+ 2373                                                   SemError(230);
+ 2374                                                   QbeGen.CopyOp("0", q)
+ 2375                                                 ELSE QbeGen.CopyOp("@", q)
+ 2376                                                 END
+ 2377                                               ELSE QbeGen.CopyOp("0", q);
+ 2378                                                 IF k = SymTab.KindImport THEN
+ 2379                                                   SemError(230)
+ 2380                                                 ELSIF k =
+ 2381                                                    SymTab.KindProc THEN
+ 2382                                                   (* bare procedure name:
+ 2383                                                      a following ArgList
+ 2384                                                      makes it a call;
+ 2385                                                      otherwise Fact
+ 2386                                                      reports 230 *)
+ 2387                                                 ELSE
+ 2388                                                    IF k = SymTab.KindField THEN
+ 2389                                                      IF QbeGen.TopWith(qb) THEN
+ 2390                                                        sfx := TRUE
+ 2391                                                      ELSE SemError(230);
+ 2392                                                        QbeGen.CopyOp("0", q)
+ 2393                                                      END
+ 2394                                                    END
+ 2395                                                 END
+ 2396                                               END
+ 2397                                             END; .)
+ 2398        (. astDes := AST.MakeNode(AST.NkDesignator);
+ 2399           AST.SetChild(astDes, AST.NChild(astDes), AST.MakeLeaf(AST.NkIdent, n));
+ 2400           IF fwd THEN AST.SetOp(astDes, 1) END;
+ 2401            IF fwd THEN Check.NoteForward(fref, astDes) END; .)
+ 2402        { "[" Expr<it, iq>
+ 2403                                          (. AST.SetChild(astDes, AST.NChild(astDes),
+ 2404               AST.MakeUn(AST.NkSelector, AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
+ 2405                                             ELSIF SymTab.ClassOf(t) #
+ 2406                                                   SymTab.ClArray THEN
+ 2407                                               SemError(217);
+ 2408                                               t := SymTab.InvalidType
+ 2409                                             ELSIF NOT SymTab.IsIntFamily(it)
+ 2410   AND (SymTab.ClassOf(it) #
+ 2411                                                   SymTab.ClChar)
+ 2412   AND (SymTab.ClassOf(it) #
+ 2413                                                   SymTab.ClEnum) THEN
+ 2414                                               SemError(218);
+ 2415                                               t := SymTab.InvalidType
+ 2416                                              ELSE
+ 2417                                                eT := SymTab.ArrayElem(t);
+ 2418                                                t := eT; sfx := TRUE
+ 2419                                              END; .)
+ 2420          { "," Expr<it, iq>
+ 2421                                          (. AST.SetChild(astDes, AST.NChild(astDes),
+ 2422               AST.MakeUn(AST.NkSelector, AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
+ 2423                                             ELSIF SymTab.ClassOf(t) #
+ 2424                                                   SymTab.ClArray THEN
+ 2425                                               SemError(217);
+ 2426                                               t := SymTab.InvalidType
+ 2427                                             ELSIF NOT SymTab.IsIntFamily(it)
+ 2428   AND (SymTab.ClassOf(it) #
+ 2429                                                   SymTab.ClChar)
+ 2430   AND (SymTab.ClassOf(it) #
+ 2431                                                   SymTab.ClEnum) THEN
+ 2432                                               SemError(218);
  2433                                               t := SymTab.InvalidType
- 2434                                             ELSIF (SymTab.ClassOf(t) =
- 2435                                                    SymTab.ClClass)
- 2436    AND SymTab.MethodExists(t, fn) THEN
- 2437                                               (* obj.Method: bind the
- 2438                                                  method and pass obj as
- 2439                                                  the hidden receiver; q
- 2440                                                  already holds the
- 2441                                                  object's address *)
- 2442                                               QbeGen.CopyOp(fn, n);
- 2443                                               QbeGen.CopyOp(fn, qn);
- 2444                                               methCls := t;
- 2445                                               k := SymTab.KindProc;
- 2446                                               t := SymTab.InvalidType
- 2447                                             ELSIF NOT SymTab.FieldExists(t,
- 2448                                                      fn) THEN
- 2449                                               SemError(216);
- 2450                                               t := SymTab.InvalidType
- 2451                                              ELSE
- 2452                                                t := SymTab.FieldType(t, fn);
- 2453                                                sfx := TRUE
- 2454                                              END; .)
- 2455        | "^"
- 2456                                          (. astSel := AST.MakeNode(AST.NkSelector);
- 2457               AST.SetOp(astSel, AST.SelDeref);
- 2458               AST.SetChild(astDes, AST.NChild(astDes), astSel); IF t = SymTab.InvalidType THEN
- 2459                                             ELSIF SymTab.ClassOf(t) #
- 2460                                                   SymTab.ClPtr THEN
- 2461                                               SemError(219);
- 2462                                               t := SymTab.InvalidType
- 2463                                             ELSE
- 2464                                               bt := SymTab.PtrBase(t);
- 2465                                               IF bt = SymTab.InvalidType THEN
- 2466                                               ELSE
- 2467                                                  t := bt;
- 2468                                                  sfx := TRUE
- 2469                                                END
- 2470                                             END; .) } (. astCur := astDes; .) .
- 2471    (* Result suffix (ISO component after a function call): `F()^`,
- 2472       `F()[i]`, `F().field`.  The call result is in t/q with sfx FALSE
- 2473       (a value, or a descriptor address for aggregates); each component
- 2474       descends one level exactly like the Design components. *)
- 2475    ResultComp<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal;
- 2476               VAR sfx: BOOLEAN; VAR node: AST.Node;
- 2477               VAR mname: SymTab.Name; VAR methCls: SymTab.TypeIndex;
- 2478               VAR isM: BOOLEAN>          (. VAR it, eT, bt: SymTab.TypeIndex;
- 2479                                               iq, ql, qlo, qhi, qe, qb:
- 2480                                                 QbeGen.QVal;
- 2481                                               lo, hi, fo: INTEGER;
- 2482                                               isOpen: BOOLEAN;
- 2483                                               fname: SymTab.Name;
- 2484                                               astWrap, astSel: AST.Node; .)
- 2485      = "[" Expr<it, iq>
- 2486                                          (. isM := FALSE;
- 2487                                             IF AST.Kind(node) # AST.NkDesignator THEN
- 2488                                               astWrap := AST.MakeNode(
- 2489                                                 AST.NkDesignator);
- 2490                                               AST.SetChild(astWrap, 0, node);
- 2491                                               node := astWrap
- 2492                                             END;
- 2493                                             AST.SetChild(node, AST.NChild(node),
- 2494                                               AST.MakeUn(AST.NkSelector,
- 2495                                                 AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
- 2496                                             ELSIF SymTab.ClassOf(t) #
- 2497                                                   SymTab.ClArray THEN
- 2498                                               SemError(217);
- 2499                                               t := SymTab.InvalidType
- 2500                                             ELSIF NOT SymTab.IsIntFamily(it)
- 2501    AND (SymTab.ClassOf(it) # SymTab.ClChar)
- 2502    AND (SymTab.ClassOf(it) # SymTab.ClEnum) THEN
- 2503                                               SemError(218);
- 2504                                               t := SymTab.InvalidType
- 2505                                              ELSE
- 2506                                                eT := SymTab.ArrayElem(t);
- 2507                                                t := eT; sfx := TRUE
- 2508                                              END; .)
- 2509        "]"
- 2510      | "." GetIdent<fname>
- 2511                                          (. isM := FALSE;
- 2512                                             IF AST.Kind(node) # AST.NkDesignator THEN
- 2513                                               astWrap := AST.MakeNode(
- 2514                                                 AST.NkDesignator);
- 2515                                               AST.SetChild(astWrap, 0, node);
- 2516                                               node := astWrap
- 2517                                             END;
- 2518                                             AST.SetChild(node, AST.NChild(node),
- 2519                                               AST.MakeUn(AST.NkSelector,
- 2520                                                 AST.SelField,
- 2521                                                 AST.MakeLeaf(AST.NkIdent,
- 2522                                                   fname))); IF t = SymTab.InvalidType THEN
- 2523                                             ELSIF (SymTab.ClassOf(t) #
- 2524                                                    SymTab.ClRecord)
- 2525    AND (SymTab.ClassOf(t) # SymTab.ClClass) THEN
- 2526                                               SemError(215);
- 2527                                               t := SymTab.InvalidType
- 2528                                              ELSIF (SymTab.ClassOf(t) =
- 2529                                                     SymTab.ClClass)
- 2530    AND SymTab.MethodExists(t, fname) THEN
- 2531                                                (* a method on the call result:
- 2532                                                   a following ArgList makes
- 2533                                                   the call *)
- 2534                                                mname := fname;
- 2535                                                methCls := t; isM := TRUE;
- 2536                                                t := SymTab.InvalidType
- 2537                                             ELSIF NOT SymTab.FieldExists(t,
- 2538                                                      fname) THEN
- 2539                                               SemError(216);
- 2540                                               t := SymTab.InvalidType
- 2541                                              ELSE
- 2542                                                t := SymTab.FieldType(t, fname);
- 2543                                                sfx := TRUE
- 2544                                              END; .)
- 2545      | "^"                               (. isM := FALSE;
- 2546                                             IF AST.Kind(node) # AST.NkDesignator THEN
- 2547                                               astWrap := AST.MakeNode(
- 2548                                                 AST.NkDesignator);
- 2549                                               AST.SetChild(astWrap, 0, node);
- 2550                                               node := astWrap
- 2551                                             END;
- 2552                                             astSel := AST.MakeNode(AST.NkSelector);
- 2553                                             AST.SetOp(astSel, AST.SelDeref);
- 2554                                             AST.SetChild(node,
- 2555                                               AST.NChild(node), astSel); IF t = SymTab.InvalidType THEN
- 2556                                             ELSIF SymTab.ClassOf(t) #
- 2557                                                   SymTab.ClPtr THEN
- 2558                                               SemError(219);
- 2559                                               t := SymTab.InvalidType
- 2560                                             ELSE
- 2561                                               bt := SymTab.PtrBase(t);
- 2562                                               IF bt # SymTab.InvalidType THEN
- 2563                                                  t := bt; sfx := TRUE
- 2564                                               END
- 2565                                             END; .) .
- 2566    Expr<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 2567                                          (. VAR t2: SymTab.TypeIndex;
- 2568                                               op: INTEGER;
- 2569                                               q2, qt, wl: QbeGen.QVal;
- 2570                                                astA, astB: AST.Node;
- 2571                                                astOp: INTEGER;
- 2572                                                astMade: BOOLEAN;
- 2573                                               isR: BOOLEAN; .)
- 2574      = SimExpr<t, q>                     (. astA := astCur; astMade := FALSE; .)
- 2575        [ Rel<op> SimExpr<t2, q2>
- 2576          (. astB := astCur; astMade := TRUE;
- 2577              astOp := AST.OpEq;
- 2578              IF op = SymTab.OpNeq1 THEN astOp := AST.OpNe
- 2579              ELSIF op = SymTab.OpNeq2 THEN astOp := AST.OpNe
- 2580              ELSIF op = SymTab.OpLt THEN astOp := AST.OpLt
- 2581              ELSIF op = SymTab.OpLe THEN astOp := AST.OpLe
- 2582              ELSIF op = SymTab.OpGt THEN astOp := AST.OpGt
- 2583              ELSIF op = SymTab.OpGe THEN astOp := AST.OpGe
- 2584              ELSIF op = SymTab.OpIn THEN astOp := AST.OpIn
- 2585              END;
- 2586              IF op = SymTab.OpIn THEN
- 2587               IF SymTab.InCheck(t, t2) THEN
- 2588                 IF (t = SymTab.InvalidType)
- 2589                    OR (t2 = SymTab.InvalidType) THEN
- 2590                   t := SymTab.BoolType(); QbeGen.CopyOp("0", q)
- 2591                 ELSE
- 2592                    t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
- 2593                 END
- 2594               ELSE SemError(222); t := SymTab.InvalidType;
- 2595                 QbeGen.CopyOp("0", q)
- 2596               END
- 2597             ELSIF SymTab.RelCheck(t, t2, op) THEN
- 2598               IF (t = SymTab.InvalidType)
- 2599                  OR (t2 = SymTab.InvalidType) THEN
- 2600                 t := SymTab.BoolType(); QbeGen.CopyOp("0", q)
- 2601               ELSIF (SymTab.ClassOf(t) = SymTab.ClPtr)
- 2602                  OR (SymTab.ClassOf(t2) = SymTab.ClPtr) THEN
- 2603                 IF (op # SymTab.OpEq) AND (op # SymTab.OpNeq1)
- 2604   AND (op # SymTab.OpNeq2) THEN
- 2605                   SemError(213); t := SymTab.InvalidType;
- 2606                   QbeGen.CopyOp("0", q)
- 2607                  ELSE
- 2608                    t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
- 2609                  END
- 2610                ELSIF (SymTab.ClassOf(t) = SymTab.ClSet)
- 2611                   OR (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
- 2612                  t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
- 2613               ELSIF SymTab.StrCompat(t, t2) THEN
- 2614                 QbeGen.StrEq(op, q, q2, qt);
- 2615                 t := SymTab.BoolType(); QbeGen.CopyOp(qt, q)
- 2616               ELSIF SymTab.IsLongFamily(t)
- 2617                  OR SymTab.IsLongFamily(t2) THEN
- 2618                  t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
- 2619                ELSE
- 2620                  t := SymTab.BoolType();
- 2621                  QbeGen.CopyOp("@", q)
- 2622                END
- 2623             ELSE SemError(213); t := SymTab.InvalidType;
- 2624                QbeGen.CopyOp("0", q)
- 2625              END;
- 2626              astCur := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB); .) ]
- 2627         (. IF NOT astMade THEN astCur := astA END; .)
- 2628             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
- 2629    Rel<VAR op: INTEGER>
- 2630      = "="                               (. op := SymTab.OpEq; .)
- 2631      | "#"                               (. op := SymTab.OpNeq1; .)
- 2632      | "<"                               (. op := SymTab.OpLt; .)
- 2633      | "<="                              (. op := SymTab.OpLe; .)
- 2634      | ">"                               (. op := SymTab.OpGt; .)
- 2635      | ">="                              (. op := SymTab.OpGe; .)
- 2636      | "IN"                              (. op := SymTab.OpIn; .) .
- 2637    SimExpr<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 2638                                          (. VAR t2, res2, lt, rt:
- 2639                                                 SymTab.TypeIndex;
- 2640                                               op: INTEGER;
- 2641                                               q2, qt, wq, qf, q2a, q2b:
- 2642                                                 QbeGen.QVal;
- 2643                                               neg, isR, isL, folded:
- 2644                                                 BOOLEAN;
- 2645                                               fok: BOOLEAN;
- 2646                                               lw, rw, mw: CARDINAL;
- 2647                                               lTrue, lNext, lDone, qr, qs: QbeGen.QVal;
- 2648                                                astA, astB: AST.Node;
- 2649                                                astSign, astOp: INTEGER; .)
- 2650      =                                   (. neg := FALSE; astSign := 0; .)
- 2651        [ "+"                         (. neg := TRUE; astSign := 1; .)
- 2652        | "-"                         (. neg := TRUE; astSign := -1; .) ]
- 2653        Term<t, q> (. astA := astCur;
- 2654                                            IF neg AND QbeGen.IsImm(q) THEN
- 2655                                              QbeGen.NegFold(q, q)
- 2656                                            END;
- 2657                                           IF astSign < 0 THEN
- 2658                                             astCur := AST.MakeUn(
- 2659                                               AST.NkUnary, AST.OpSub, astA);
- 2660                                             astA := astCur
- 2661                                           END; .)
- 2662         { AddOp<op>
- 2663           Term<t2, q2> (. astB := astCur; .)
- 2664          (. astOp := AST.OpAdd;
- 2665             IF op = SymTab.OpSub THEN astOp := AST.OpSub
- 2666             ELSIF op = SymTab.OpOr THEN astOp := AST.OpOr END;
- 2667             astA := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB);
- 2668             astCur := astA;
- 2669             IF op = SymTab.OpOr THEN
- 2670               (* short-circuit: if q is true the RHS is skipped *)
- 2671               IF SymTab.BoolCheck(t) AND SymTab.BoolCheck(t2) THEN
- 2672                 t := SymTab.BoolType()
- 2673               ELSE SemError(212); t := SymTab.InvalidType END;
- 2674                IF t # SymTab.InvalidType THEN
- 2675                  QbeGen.CopyOp("@", q)
- 2676                ELSE QbeGen.CopyOp("0", q)
- 2677                END
- 2678             ELSIF (op = SymTab.OpAdd)
- 2679               AND (SymTab.UStrCompat(t, t2)
- 2680                 OR ((SymTab.ClassOf(t) = SymTab.ClUChar)
- 2681                   AND (SymTab.ClassOf(t2) = SymTab.ClUStr))
- 2682                 OR ((SymTab.ClassOf(t) = SymTab.ClUStr)
- 2683                   AND (SymTab.ClassOf(t2) = SymTab.ClUChar))
- 2684                 OR ((SymTab.ClassOf(t) = SymTab.ClUChar)
- 2685                   AND (SymTab.ClassOf(t2) = SymTab.ClUChar))) THEN
- 2686               (* UString concatenation: a UCHAR operand becomes a
- 2687                  1-codepoint UString; the result is a descriptor in the
- 2688                  shim's concat buffer.  Work on copies so neither
- 2689                  operand is clobbered. *)
- 2690                t := SymTab.NewUStr();
- 2691                QbeGen.CopyOp("@", q)
- 2692             ELSIF (op = SymTab.OpAdd)
- 2693               AND (SymTab.StrCompat(t, t2)
- 2694                 OR (SymTab.IsStrType(t)
- 2695                   AND (SymTab.ClassOf(t2) = SymTab.ClChar))
- 2696                 OR ((SymTab.ClassOf(t) = SymTab.ClChar)
- 2697                   AND SymTab.IsStrType(t2))) THEN
- 2698               (* string concatenation; a CHAR operand becomes a
- 2699                  1-character string literal.  When both operands are
- 2700                  constants, fold to a single string literal so a
- 2701                  constructor element stays compile-time. *)
- 2702                QbeGen.StrFold(q, q2, SymTab.ClassOf(t), SymTab.ClassOf(t2),
- 2703                  qt, fok);
- 2704                IF fok THEN QbeGen.CopyOp(qt, q)
- 2705                ELSE QbeGen.CopyOp("@", q)
- 2706                END;
- 2707                t := SymTab.NewStr()
- 2708             ELSIF (t # SymTab.InvalidType) AND (t2 # SymTab.InvalidType)
- 2709   AND (SymTab.ClassOf(t) = SymTab.ClSet)
- 2710   AND (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
- 2711                lw := SymTab.SetWords(t); rw := SymTab.SetWords(t2);
- 2712                mw := lw;
- 2713                IF rw > mw THEN mw := rw END;
- 2714                t := SymTab.NewSet(
- 2715                       SymTab.NewSubR(0,
- 2716                         VAL(INTEGER, mw) * 32 - 1));
- 2717                QbeGen.CopyOp("@", q)
- 2718             ELSE
- 2719               IF SymTab.ArithCheck(t, t2, FALSE, res2) THEN
- 2720                 lt := t; rt := t2; t := res2
- 2721               ELSE SemError(211); t := SymTab.InvalidType END;
- 2722               IF t # SymTab.InvalidType THEN
- 2723                 isL := SymTab.IsLongFamily(t);
- 2724                 isR := SymTab.ClassOf(t) = SymTab.ClReal;
- 2725                 folded := FALSE;
- 2726                 IF (NOT isL) AND (NOT isR)
- 2727    AND QbeGen.IsImm(q) AND QbeGen.IsImm(q2) THEN
- 2728                   IF op = SymTab.OpAdd THEN
- 2729                     folded := QbeGen.Fold2(0, q, q2, qf)
- 2730                   ELSE
- 2731                     folded := QbeGen.Fold2(1, q, q2, qf)
- 2732                   END
- 2733                 END;
- 2734                 IF folded THEN QbeGen.CopyOp(qf, q)
- 2735                  ELSE
- 2736                  QbeGen.CopyOp("@", q)
- 2737                  END
- 2738               ELSE QbeGen.CopyOp("0", q)
- 2739               END
- 2740             END; .) }
- 2741             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
- 2742    AddOp<VAR op: INTEGER>
- 2743      = "+"                               (. op := SymTab.OpAdd; .)
- 2744      | "-"                               (. op := SymTab.OpSub; .)
- 2745      | "OR"                              (. op := SymTab.OpOr; .) .
- 2746    Term<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 2747                                          (. VAR t2, res2, lt, rt:
- 2748                                                 SymTab.TypeIndex;
- 2749                                               op: INTEGER;
- 2750                                               q2, qt, wq, qf:
- 2751                                                 QbeGen.QVal;
- 2752                                               isR, isL, folded: BOOLEAN;
- 2753                                               lw, rw, mw: CARDINAL;
- 2754                                               lNext, lFalse, lDone, qr, qs: QbeGen.QVal;
- 2755                                                astA, astB: AST.Node;
- 2756                                                astOp: INTEGER; .)
- 2757      = Fact<t, q> (. astA := astCur; .) { MulOp<op>
- 2758          Fact<t2, q2> (. astB := astCur; .)
- 2759        (. astOp := AST.OpMul;
- 2760           IF op = SymTab.OpSlash THEN astOp := AST.OpDiv
- 2761           ELSIF op = SymTab.OpDiv THEN astOp := AST.OpDiv
- 2762           ELSIF op = SymTab.OpMod THEN astOp := AST.OpMod
- 2763           ELSIF op = SymTab.OpAnd THEN astOp := AST.OpAnd END;
- 2764           astA := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB);
- 2765           astCur := astA;
- 2766           IF op = SymTab.OpAnd THEN
- 2767             (* short-circuit: if q is false the RHS is skipped *)
- 2768             IF SymTab.BoolCheck(t) AND SymTab.BoolCheck(t2) THEN
- 2769               t := SymTab.BoolType()
- 2770             ELSE SemError(212); t := SymTab.InvalidType END;
- 2771              IF t # SymTab.InvalidType THEN QbeGen.CopyOp("@", q)
- 2772              ELSE QbeGen.CopyOp("0", q)
- 2773              END
- 2774           ELSIF (t # SymTab.InvalidType) AND (t2 # SymTab.InvalidType)
- 2775   AND (SymTab.ClassOf(t) = SymTab.ClSet)
- 2776   AND (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
- 2777              lw := SymTab.SetWords(t); rw := SymTab.SetWords(t2);
- 2778              mw := lw;
- 2779              IF rw > mw THEN mw := rw END;
- 2780              t := SymTab.NewSet(
- 2781                     SymTab.NewSubR(0,
- 2782                       VAL(INTEGER, mw) * 32 - 1));
- 2783              QbeGen.CopyOp("@", q)
- 2784           ELSE
- 2785             IF SymTab.ArithCheck(t, t2,
- 2786                  (op = SymTab.OpDiv) OR (op = SymTab.OpMod),
- 2787                  res2) THEN
- 2788               lt := t; rt := t2; t := res2
- 2789             ELSE SemError(211); t := SymTab.InvalidType END;
- 2790             IF t # SymTab.InvalidType THEN
- 2791               isL := SymTab.IsLongFamily(t);
- 2792               isR := SymTab.ClassOf(t) = SymTab.ClReal;
- 2793               folded := FALSE;
- 2794               IF (NOT isL) AND (NOT isR)
- 2795    AND QbeGen.IsImm(q) AND QbeGen.IsImm(q2) THEN
- 2796                 IF op = SymTab.OpTimes THEN
- 2797                   folded := QbeGen.Fold2(2, q, q2, qf)
- 2798                 ELSIF op = SymTab.OpDiv THEN
- 2799                   folded := QbeGen.Fold2(3, q, q2, qf)
- 2800                 ELSIF op = SymTab.OpMod THEN
- 2801                   folded := QbeGen.Fold2(4, q, q2, qf)
- 2802                 END
- 2803               END;
- 2804               IF folded THEN QbeGen.CopyOp(qf, q)
- 2805                ELSE
- 2806                QbeGen.CopyOp("@", q)
- 2807                END
- 2808             ELSE QbeGen.CopyOp("0", q)
- 2809             END
- 2810           END; .) }
- 2811             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
- 2812    MulOp<VAR op: INTEGER>
- 2813      = "*"                               (. op := SymTab.OpTimes; .)
- 2814      | "/"                               (. op := SymTab.OpSlash; .)
- 2815      | "DIV"                             (. op := SymTab.OpDiv; .)
- 2816      | "MOD"                             (. op := SymTab.OpMod; .)
- 2817      | ( "AND" | "&" )                   (. op := SymTab.OpAnd; .) .
- 2818    Fact<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 2819                                          (. VAR s: ARRAY [0 .. 255] OF CHAR;
- 2820                                               et, dt, t2, st, ct2, et2:
- 2821                                                 SymTab.TypeIndex;
- 2822                                               dk: INTEGER;
- 2823                                               qd, q2, sq, qa, qm0, qr, qt:
- 2824                                                 QbeGen.QVal;
- 2825                                               qn, vn: SymTab.Name;
- 2826                                               vt: SymTab.TypeIndex;
- 2827                                               c1, c2: INTEGER;
- 2828                                               lo, hi: INTEGER;
- 2829                                               isMax: BOOLEAN;
- 2830                                               called, isHigh, sfx, isCh,
- 2831                                               isU, uok, isStr: BOOLEAN;
- 2832                                               ucp: INTEGER; astIsLit: BOOLEAN;
- 2833                                                astD: AST.Node;
- 2834                                                astCall: BOOLEAN;
- 2835                                                astNode, astNot: AST.Node;
- 2836                                                j: CARDINAL;
- 2837                                                astArg2: AST.Node;
- 2838                                                astBrace: AST.Node;
- 2839                                                astRes: AST.Node; mname: SymTab.Name; isM: BOOLEAN; .)
- 2840      = (. astIsLit := FALSE; .)
- 2841      ( integer                           (. LexString(s);
- 2842                                             QbeGen.NormInt(s, q); IF twoPhase THEN astIsLit := TRUE; astCur := AST.MakeLeaf(AST.NkIntLit, s) END;
- 2843                                             t := SymTab.IntType(); .)
- 2844      | charConst                         (. LexString(s);
- 2845                                             QbeGen.NormLit(s, q, isCh);
- 2846                                             IF twoPhase THEN
- 2847                                               astIsLit := TRUE;
- 2848                                               astCur := AST.MakeLeaf(
- 2849                                                 AST.NkCharLit, s)
- 2850                                             END;
- 2851                                             t := SymTab.CharType(); .)
- 2852      | real                              (. LexString(s);
- 2853                                             QbeGen.NormReal(s, q);
- 2854                                             IF twoPhase THEN
- 2855                                               astIsLit := TRUE;
- 2856                                               astCur := AST.MakeLeaf(
- 2857                                                 AST.NkRealLit, s)
- 2858                                             END;
- 2859                                             t := SymTab.RealType(); .)
- 2860      | string                            (. LexString(s);
- 2861                                             IF twoPhase THEN
- 2862                                               astIsLit := TRUE;
- 2863                                               astCur := AST.MakeLeaf(
- 2864                                                 AST.NkStrLit, s)
- 2865                                             END;
- 2866                                             IF SymTab.StrLen(s) = 3 THEN
- 2867                                               t := SymTab.CharType();
- 2868                                               QbeGen.IntStr(
- 2869                                                 QbeGen.CharVal(s), q)
- 2870                                             ELSE t := SymTab.NewStr();
- 2871                                               QbeGen.DeclStr(s, q);
- 2872                                               (* a literal's value IS its
- 2873                                                  static descriptor address *)
- 2874                                             END; .)
- 2875      | ustring                           (. LexString(s);
- 2876                                             IF twoPhase THEN
- 2877                                               astIsLit := TRUE;
- 2878                                               astCur := AST.MakeLeaf(
- 2879                                                 AST.NkStrLit, s)
- 2880                                             END;
- 2881                                             QbeGen.DeclUStr(s, q, isU, ucp,
- 2882                                               uok);
- 2883                                             IF NOT uok THEN
- 2884                                               SemError(234);
- 2885                                               t := SymTab.InvalidType
- 2886                                             ELSIF isU THEN
- 2887                                               t := SymTab.UCharType();
- 2888                                               QbeGen.IntStr(ucp, q)
- 2889                                             ELSE
- 2890                                               t := SymTab.NewUStr();
- 2891                                             END; .)
- 2892      | Design<dt, dk, qd, qn, sfx>       (. astD := astCur; astCall := FALSE; astBrace := AST.NoNode;
- 2893                                             astNArgs := 0; called := FALSE;
- 2894                                             t := dt;
- 2895                                             IF dk = SymTab.KindConst THEN
- 2896                                               QbeGen.CopyOp(qd, q)
- 2897                                             ELSE QbeGen.CopyOp("@", q)
- 2898                                             END; .)
- 2899        [ TypedBraceLit<dt, q>            (. t := dt; astCall := TRUE;
- 2900                                               astBrace := astCur; .) ]
- 2901        [ ArgList<qn, dt, qd, TRUE, FALSE, methCls, ct2, q2, called>
- 2902                                          (. astCall := TRUE;
- 2903                                             astNode := AstCallNode(astD);
- 2904                                             astRes := astNode;
- 2905                                             t := ct2;
- 2906                                             QbeGen.CopyOp(q2, q);
- 2907                                             sfx := FALSE; .)
- 2908          { ResultComp<t, q, sfx, astRes, mname, methCls, isM>
- 2909            [ (. astNArgs := 0; .)
- 2910              ArgList<mname, t, q, TRUE, FALSE, methCls, ct2, q2, called>
- 2911                                          (. astNode := AstCallNode(astRes);
- 2912                                             astRes := astNode;
- 2913                                             t := ct2;
- 2914                                             QbeGen.CopyOp(q2, q);
- 2915                                             sfx := FALSE; .) ] }
- 2916                                          (. IF sfx THEN
- 2917                                               IF t = SymTab.InvalidType THEN
- 2918                                                 QbeGen.CopyOp("0", q)
- 2919                                               ELSIF (SymTab.ClassOf(t) #
- 2920                                                      SymTab.ClRecord)
- 2921    AND (SymTab.ClassOf(t) # SymTab.ClSet)
- 2922    AND (SymTab.ClassOf(t) # SymTab.ClArray)
- 2923    AND (SymTab.ClassOf(t) # SymTab.ClClass) THEN
- 2924                                                  QbeGen.CopyOp("@", q)
- 2925                                               END
- 2926                                             END; .) ]
- 2927                                          (. IF called THEN
- 2928                                               astCur := astRes
- 2929                                             ELSIF astCall THEN
- 2930                                               astCur := astBrace
- 2931                                             ELSE astCur := astD
- 2932                                             END;
- 2933                                              astIsLit := TRUE;
- 2934                                              IF NOT called
- 2935   AND (dk = SymTab.KindProc) THEN
- 2936                                               (* bare zero-arg function
- 2937                                                  call (parentheses may be
- 2938                                                  omitted); a proper or
- 2939                                                  parameterised proc here
- 2940                                                  is 230 *)
- 2941                                                IF (SymTab.ProcNPar(qn) = 0)
- 2942   AND (SymTab.ProcRes(qn) # SymTab.InvalidType) THEN
- 2943                                                  t := SymTab.ProcRes(qn);
- 2944                                                  QbeGen.CopyOp("@", q);
- 2945                                                  astCur := AST.MakeNode(AST.NkCall);
- 2946                                                  AST.SetChild(astCur, 0, astD)
- 2947                                                ELSE
- 2948                                                  t := SymTab.ProcTypeOf(qn);
- 2949                                                  QbeGen.CopyOp("@", q)
- 2950                                                END
- 2951                                             END; .)
- 2952      | ( "HIGH"                          (. isHigh := TRUE; .)
- 2953        | ( "LEN" | "LENGTH" )            (. isHigh := FALSE; .) )
- 2954        "(" ( Design<dt, dk, qd, qn, sfx> (. isStr := FALSE;
- 2955                                              isU := FALSE; .)
- 2956            | string                       (. LexString(s); astCur := AST.MakeLeaf(AST.NkStrLit, s);
- 2957                                              isStr := TRUE;
- 2958                                              isU := FALSE;
- 2959                                              IF SymTab.StrLen(s) = 3 THEN
- 2960                                                dt := SymTab.CharType();
- 2961                                                QbeGen.IntStr(QbeGen.CharVal(s),
- 2962                                                  qd)
- 2963                                              ELSE
- 2964                                                dt := SymTab.NewStr();
- 2965                                                QbeGen.DeclStr(s, qd);
- 2966                                              END;
- 2967                                              dk := -1;
- 2968                                              qn[0] := CHR(0); .)
- 2969            | ustring                      (. LexString(s); astCur := AST.MakeLeaf(AST.NkStrLit, s);
- 2970                                              QbeGen.DeclUStr(s, qd, isU, ucp,
- 2971                                                uok);
- 2972                                              isStr := FALSE;
- 2973                                              IF NOT uok THEN
- 2974                                                SemError(234);
- 2975                                                dt := SymTab.InvalidType
- 2976                                              ELSIF isU THEN
- 2977                                                (* one codepoint: a UCHAR;
- 2978                                                   LEN is 1, HIGH is 0 *)
- 2979                                                dt := SymTab.UCharType();
- 2980                                                QbeGen.IntStr(ucp, qd)
- 2981                                              ELSE
- 2982                                                dt := SymTab.NewUStr();
- 2983                                              END;
- 2984                                              dk := -1;
- 2985                                              qn[0] := CHR(0); .) )
- 2986        ")"
- 2987                                          (. astNode := AST.MakeNode(AST.NkCall);
- 2988     IF isHigh THEN AST.SetChild(astNode, 0,
- 2989       AST.MakeLeaf(AST.NkIdent, "HIGH"))
- 2990     ELSE AST.SetChild(astNode, 0,
- 2991       AST.MakeLeaf(AST.NkIdent, "LEN")) END;
- 2992     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 2993     astCur := astNode; astIsLit := TRUE;
- 2994                                             IF (dt # SymTab.InvalidType)
- 2995    AND (SymTab.ClassOf(dt) = SymTab.ClUStr) THEN
- 2996                                               (* UString: the count is
- 2997                                                  the descriptor header *)
- 2998                                                t := SymTab.IntType();
- 2999                                                QbeGen.CopyOp("@", q)
- 3000                                             ELSIF (dt # SymTab.InvalidType)
- 3001    AND (SymTab.ClassOf(dt) = SymTab.ClUChar) THEN
- 3002                                               (* single UCHAR codepoint *)
- 3003                                               IF isHigh THEN
- 3004                                                 QbeGen.CopyOp("0", qr)
- 3005                                               ELSE
- 3006                                                 QbeGen.CopyOp("1", qr)
- 3007                                               END;
- 3008                                               t := SymTab.IntType();
- 3009                                               QbeGen.CopyOp(qr, q)
- 3010                                             ELSIF isStr THEN
- 3011                                               (* fold: content length at
- 3012                                                  compile time *)
- 3013                                               IF SymTab.StrLen(s) = 3 THEN
- 3014                                                 c1 := 1
- 3015                                               ELSE
- 3016                                                 c1 :=
- 3017                                                   SymTab.StrLen(s) - 2
- 3018                                               END;
- 3019                                               IF isHigh THEN
- 3020                                                 DEC(c1)
- 3021                                               END;
- 3022                                               QbeGen.IntStr(c1, qr);
- 3023                                               t := SymTab.IntType();
- 3024                                               QbeGen.CopyOp(qr, q)
- 3025                                             ELSIF dt = SymTab.InvalidType THEN
- 3026                                               t := SymTab.InvalidType;
- 3027                                               QbeGen.CopyOp("0", q)
- 3028                                             ELSIF SymTab.ClassOf(dt) #
- 3029                                                   SymTab.ClArray THEN
- 3030                                               SemError(217);
- 3031                                               t := SymTab.InvalidType;
- 3032                                               QbeGen.CopyOp("0", q)
- 3033                                             ELSE
- 3034                                                IF SymTab.IsOpenArray(dt) THEN
- 3035                                                  t := SymTab.IntType();
- 3036                                                  QbeGen.CopyOp("@", q)
- 3037                                                ELSE
- 3038                                                  IF isHigh THEN
- 3039                                                    QbeGen.IntStr(
- 3040                                                      SymTab.ArrayHi(dt), qr)
- 3041                                                  ELSE
- 3042                                                    QbeGen.IntStr(VAL(
- 3043                                                      INTEGER,
- 3044                                                      SymTab.ArrayLen(dt)),
- 3045                                                      qr)
- 3046                                                  END;
- 3047                                                  t := SymTab.IntType();
- 3048                                                  QbeGen.CopyOp(qr, q)
- 3049                                                END
- 3050                                              END; .)
- 3051      | ( "SIZE" | "TSIZE" ) "(" Design<dt, dk, qd, qn, sfx> ")"
- 3052      (. astNode := AST.MakeNode(AST.NkCall);
- 3053     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "SIZE"));
- 3054     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3055     astCur := astNode; astIsLit := TRUE; .)
- 3056                                          (. IF dt = SymTab.InvalidType THEN
- 3057                                               t := SymTab.InvalidType;
- 3058                                               QbeGen.CopyOp("0", q)
- 3059                                             ELSE
- 3060                                               QbeGen.IntStr(VAL(INTEGER,
- 3061                                                 SymTab.ObjectSize(dt)), q);
- 3062                                               t := SymTab.IntType()
- 3063                                             END; .)
- 3064      | ( "SHIFT"                         (. isMax := FALSE; .)
- 3065        | "ROTATE"                        (. isMax := TRUE; .) )
- 3066        "(" Expr<et, q> (. astArg2 := astCur; .) "," Expr<et2, q2> ")"
- 3067                                          (. astNode := AST.MakeNode(AST.NkCall);
- 3068     IF isMax THEN AST.SetChild(astNode, 0,
- 3069       AST.MakeLeaf(AST.NkIdent, "ROTATE"))
- 3070     ELSE AST.SetChild(astNode, 0,
- 3071       AST.MakeLeaf(AST.NkIdent, "SHIFT")) END;
- 3072     IF astArg2 # AST.NoNode THEN AST.SetChild(astNode, 1, astArg2) END;
- 3073     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 2, astCur) END;
- 3074     astCur := astNode; astIsLit := TRUE;
- 3075                                             (* set shift/rotate: isMax
- 3076                                                doubles as "rotate" *)
- 3077                                             IF (et # SymTab.InvalidType)
- 3078                                                AND (SymTab.ClassOf(et) =
- 3079                                                   SymTab.ClSet) THEN
- 3080                                                t := et;
- 3081                                                QbeGen.CopyOp("@", q)
- 3082                                             ELSE SemError(230);
- 3083                                               t := SymTab.InvalidType;
- 3084                                               QbeGen.CopyOp("0", q)
- 3085                                             END; .)
- 3086      | ( "MIN"                           (. isMax := FALSE; .)
- 3087        | "MAX"                           (. isMax := TRUE; .) )
- 3088        "(" Design<dt, dk, qd, qn, sfx> ")"
- 3089                                          (. astNode := AST.MakeNode(AST.NkCall);
- 3090     IF isMax THEN AST.SetChild(astNode, 0,
- 3091       AST.MakeLeaf(AST.NkIdent, "MAX"))
- 3092     ELSE AST.SetChild(astNode, 0,
- 3093       AST.MakeLeaf(AST.NkIdent, "MIN")) END;
- 3094     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3095     astCur := astNode; astIsLit := TRUE;
- 3096                                             IF (dt # SymTab.InvalidType)
- 3097   AND (SymTab.ClassOf(dt) = SymTab.ClReal) THEN
- 3098                                               (* REAL/LONGREAL: the
- 3099                                                  implementation bounds *)
- 3100                                               IF isMax THEN
- 3101                                                 QbeGen.NormReal(
- 3102                                                   "3.402823e38", q)
- 3103                                               ELSE QbeGen.NormReal(
- 3104                                                   "-3.402823e38", q)
- 3105                                               END;
- 3106                                               t := SymTab.RealType()
- 3107                                             ELSIF (dt #
- 3108                                                SymTab.InvalidType)
- 3109   AND (SymTab.ClassOf(dt) =
- 3110                                                   SymTab.ClLong) THEN
- 3111                                               IF isMax THEN
- 3112                                                 QbeGen.CopyOp(
- 3113                                                   "9223372036854775807", q)
- 3114                                               ELSE QbeGen.CopyOp(
- 3115                                                   "-9223372036854775808", q)
- 3116                                               END;
- 3117                                               t := SymTab.LongType()
- 3118                                             ELSIF SymTab.TypeBounds(dt, lo,
- 3119                                                      hi) THEN
- 3120                                               IF isMax THEN
- 3121                                                 QbeGen.IntStr(hi, q)
- 3122                                               ELSE QbeGen.IntStr(lo, q)
- 3123                                               END;
- 3124                                               t := SymTab.IntType()
- 3125                                             ELSE SemError(230);
- 3126                                               t := SymTab.InvalidType;
- 3127                                               QbeGen.CopyOp("0", q)
- 3128                                             END; .)
- 3129      | "ADR" "(" Design<dt, dk, qd, qn, sfx> ")"
- 3130      (. astNode := AST.MakeNode(AST.NkCall);
- 3131     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ADR"));
- 3132     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3133     astCur := astNode; astIsLit := TRUE; .)
- 3134                                          (. IF dt = SymTab.InvalidType THEN
- 3135                                               t := SymTab.InvalidType;
- 3136                                               QbeGen.CopyOp("0", q)
- 3137                                             ELSE
- 3138                                                IF sfx
- 3139                                                   OR (dk = SymTab.KindVar)
- 3140                                                   OR (dk = SymTab.KindParam) THEN
- 3141                                                  QbeGen.CopyOp("@", q)
- 3142                                                ELSE SemError(230);
- 3143                                                  QbeGen.CopyOp("0", q)
- 3144                                                END;
- 3145                                               t := SymTab.AddrType()
- 3146                                             END; .)
- 3147      | "CHR" "(" Expr<et, q> ")"
- 3148      (. astNode := AST.MakeNode(AST.NkCall);
- 3149     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CHR"));
- 3150     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3151     astCur := astNode; astIsLit := TRUE; .)
- 3152                                          (. IF (et # SymTab.InvalidType)
- 3153   AND NOT SymTab.IsIntFamily(et) THEN
- 3154                                               SemError(211) END;
- 3155                                             t := SymTab.CharType(); .)
- 3156      | ( "ORD" | "ORDL" ) "(" Expr<et, q> ")"
- 3157      (. astNode := AST.MakeNode(AST.NkCall);
- 3158     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ORD"));
- 3159     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3160     astCur := astNode; astIsLit := TRUE; .)
- 3161                                          (. IF et # SymTab.InvalidType THEN
- 3162                                               IF (SymTab.ClassOf(et) #
- 3163                                                   SymTab.ClChar)
- 3164   AND (SymTab.ClassOf(et) #
- 3165                                                     SymTab.ClBool)
- 3166   AND (SymTab.ClassOf(et) #
- 3167                                                     SymTab.ClEnum)
- 3168   AND NOT SymTab.IsIntFamily(et) THEN
- 3169                                                 SemError(211) END
- 3170                                             END;
- 3171                                             t := SymTab.IntType(); .)
- 3172      | "CAP" "(" Expr<et, q> ")"
- 3173      (. astNode := AST.MakeNode(AST.NkCall);
- 3174     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CAP"));
- 3175     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3176     astCur := astNode; astIsLit := TRUE; .)
- 3177                                           (. QbeGen.CopyOp("@", q);
- 3178                                             t := SymTab.CharType(); .)
- 3179      | "UCHR" "(" Expr<et, q> ")"
- 3180      (. astNode := AST.MakeNode(AST.NkCall);
- 3181     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "UCHR"));
- 3182     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3183     astCur := astNode; astIsLit := TRUE; .)
- 3184                                          (. (* UCHR: the UCHAR constructor.
- 3185                                                CHAR -> UCHAR (identity);
- 3186                                                INTEGER familly -> UCHAR
- 3187                                                (codepoint value). *)
- 3188                                             IF (et # SymTab.InvalidType)
- 3189    AND (SymTab.ClassOf(et) # SymTab.ClChar)
- 3190    AND NOT SymTab.IsIntFamily(et) THEN
- 3191                                               SemError(211) END;
- 3192                                             t := SymTab.UCharType(); .)
- 3193      | "CHR8" "(" Expr<et, q> ")"
- 3194      (. astNode := AST.MakeNode(AST.NkCall);
- 3195     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CHR8"));
- 3196     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3197     astCur := astNode; astIsLit := TRUE; .)
- 3198                                          (. IF (et # SymTab.InvalidType)
- 3199    AND (SymTab.ClassOf(et) # SymTab.ClUChar) THEN
- 3200                                               SemError(211) END;
- 3201                                             t := SymTab.CharType(); .)
- 3202      | "UORD" "(" Expr<et, q> ")"
- 3203      (. astNode := AST.MakeNode(AST.NkCall);
- 3204     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "UORD"));
- 3205     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
- 3206     astCur := astNode; astIsLit := TRUE; .)
- 3207                                          (. (* UORD(u): the codepoint as a
- 3208                                                32-bit ordinal (INTEGER),
- 3209                                                cf. ORD for CHAR. *)
- 3210                                             IF (et # SymTab.InvalidType)
- 3211    AND (SymTab.ClassOf(et) # SymTab.ClUChar) THEN
- 3212                                               SemError(211) END;
- 3213                                             t := SymTab.IntType(); .)
- 3214      | "ABS" "(" Expr<et, q> ")"
+ 2434                                              ELSE
+ 2435                                                eT := SymTab.ArrayElem(t);
+ 2436                                                t := eT; sfx := TRUE
+ 2437                                              END; .) }
+ 2438          "]"
+ 2439        | "." GetIdent<fn>
+ 2440                                          (. astSel := AST.MakeNode(AST.NkSelector);
+ 2441               AST.SetOp(astSel, AST.SelField);
+ 2442               AST.SetChild(astSel, 0, AST.MakeLeaf(AST.NkIdent, fn));
+ 2443               AST.SetChild(astDes, AST.NChild(astDes), astSel); IF k = SymTab.KindModule THEN
+ 2444                                               (* qualified L.x: materialize
+ 2445                                                  the export, then load it *)
+ 2446                                               IF NOT SymTab.MaterializeAlias(n,
+ 2447                                                    fn, mal) THEN
+ 2448                                                 SemError(201);
+ 2449                                                 t := SymTab.InvalidType;
+ 2450                                                 QbeGen.CopyOp("0", q)
+ 2451                                               ELSE
+ 2452                                                 QbeGen.CopyOp(mal, qn);
+ 2453                                                 t := SymTab.SymType(mal);
+ 2454                                                 k := SymTab.SymKind(mal);
+ 2455                                                 sfx := FALSE;
+ 2456                                                 IF k = SymTab.KindProc THEN
+ 2457                                                   (* call: ArgList supplies
+ 2458                                                      the value *)
+ 2459                                                   QbeGen.CopyOp("0", q)
+ 2460                                                  END
+ 2461                                               END
+ 2462                                             ELSIF t = SymTab.InvalidType THEN
+ 2463                                             ELSIF (SymTab.ClassOf(t) #
+ 2464                                                    SymTab.ClRecord)
+ 2465   AND (SymTab.ClassOf(t) #
+ 2466                                                   SymTab.ClClass) THEN
+ 2467                                               SemError(215);
+ 2468                                               t := SymTab.InvalidType
+ 2469                                             ELSIF (SymTab.ClassOf(t) =
+ 2470                                                    SymTab.ClClass)
+ 2471    AND SymTab.MethodExists(t, fn) THEN
+ 2472                                               (* obj.Method: bind the
+ 2473                                                  method and pass obj as
+ 2474                                                  the hidden receiver; q
+ 2475                                                  already holds the
+ 2476                                                  object's address *)
+ 2477                                               QbeGen.CopyOp(fn, n);
+ 2478                                               QbeGen.CopyOp(fn, qn);
+ 2479                                               methCls := t;
+ 2480                                               k := SymTab.KindProc;
+ 2481                                               t := SymTab.InvalidType
+ 2482                                             ELSIF NOT SymTab.FieldExists(t,
+ 2483                                                      fn) THEN
+ 2484                                               SemError(216);
+ 2485                                               t := SymTab.InvalidType
+ 2486                                              ELSE
+ 2487                                                t := SymTab.FieldType(t, fn);
+ 2488                                                sfx := TRUE
+ 2489                                              END; .)
+ 2490        | "^"
+ 2491                                          (. astSel := AST.MakeNode(AST.NkSelector);
+ 2492               AST.SetOp(astSel, AST.SelDeref);
+ 2493               AST.SetChild(astDes, AST.NChild(astDes), astSel); IF t = SymTab.InvalidType THEN
+ 2494                                             ELSIF SymTab.ClassOf(t) #
+ 2495                                                   SymTab.ClPtr THEN
+ 2496                                               SemError(219);
+ 2497                                               t := SymTab.InvalidType
+ 2498                                             ELSE
+ 2499                                               bt := SymTab.PtrBase(t);
+ 2500                                               IF bt = SymTab.InvalidType THEN
+ 2501                                               ELSE
+ 2502                                                  t := bt;
+ 2503                                                  sfx := TRUE
+ 2504                                                END
+ 2505                                             END; .) } (. astCur := astDes; .) .
+ 2506    (* Result suffix (ISO component after a function call): `F()^`,
+ 2507       `F()[i]`, `F().field`.  The call result is in t/q with sfx FALSE
+ 2508       (a value, or a descriptor address for aggregates); each component
+ 2509       descends one level exactly like the Design components. *)
+ 2510    ResultComp<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal;
+ 2511               VAR sfx: BOOLEAN; VAR node: AST.Node;
+ 2512               VAR mname: SymTab.Name; VAR methCls: SymTab.TypeIndex;
+ 2513               VAR isM: BOOLEAN>          (. VAR it, eT, bt: SymTab.TypeIndex;
+ 2514                                               iq, ql, qlo, qhi, qe, qb:
+ 2515                                                 QbeGen.QVal;
+ 2516                                               lo, hi, fo: INTEGER;
+ 2517                                               isOpen: BOOLEAN;
+ 2518                                               fname: SymTab.Name;
+ 2519                                               astWrap, astSel: AST.Node; .)
+ 2520      = "[" Expr<it, iq>
+ 2521                                          (. isM := FALSE;
+ 2522                                             IF AST.Kind(node) # AST.NkDesignator THEN
+ 2523                                               astWrap := AST.MakeNode(
+ 2524                                                 AST.NkDesignator);
+ 2525                                               AST.SetChild(astWrap, 0, node);
+ 2526                                               node := astWrap
+ 2527                                             END;
+ 2528                                             AST.SetChild(node, AST.NChild(node),
+ 2529                                               AST.MakeUn(AST.NkSelector,
+ 2530                                                 AST.SelIndex, astCur)); IF t = SymTab.InvalidType THEN
+ 2531                                             ELSIF SymTab.ClassOf(t) #
+ 2532                                                   SymTab.ClArray THEN
+ 2533                                               SemError(217);
+ 2534                                               t := SymTab.InvalidType
+ 2535                                             ELSIF NOT SymTab.IsIntFamily(it)
+ 2536    AND (SymTab.ClassOf(it) # SymTab.ClChar)
+ 2537    AND (SymTab.ClassOf(it) # SymTab.ClEnum) THEN
+ 2538                                               SemError(218);
+ 2539                                               t := SymTab.InvalidType
+ 2540                                              ELSE
+ 2541                                                eT := SymTab.ArrayElem(t);
+ 2542                                                t := eT; sfx := TRUE
+ 2543                                              END; .)
+ 2544        "]"
+ 2545      | "." GetIdent<fname>
+ 2546                                          (. isM := FALSE;
+ 2547                                             IF AST.Kind(node) # AST.NkDesignator THEN
+ 2548                                               astWrap := AST.MakeNode(
+ 2549                                                 AST.NkDesignator);
+ 2550                                               AST.SetChild(astWrap, 0, node);
+ 2551                                               node := astWrap
+ 2552                                             END;
+ 2553                                             AST.SetChild(node, AST.NChild(node),
+ 2554                                               AST.MakeUn(AST.NkSelector,
+ 2555                                                 AST.SelField,
+ 2556                                                 AST.MakeLeaf(AST.NkIdent,
+ 2557                                                   fname))); IF t = SymTab.InvalidType THEN
+ 2558                                             ELSIF (SymTab.ClassOf(t) #
+ 2559                                                    SymTab.ClRecord)
+ 2560    AND (SymTab.ClassOf(t) # SymTab.ClClass) THEN
+ 2561                                               SemError(215);
+ 2562                                               t := SymTab.InvalidType
+ 2563                                              ELSIF (SymTab.ClassOf(t) =
+ 2564                                                     SymTab.ClClass)
+ 2565    AND SymTab.MethodExists(t, fname) THEN
+ 2566                                                (* a method on the call result:
+ 2567                                                   a following ArgList makes
+ 2568                                                   the call *)
+ 2569                                                mname := fname;
+ 2570                                                methCls := t; isM := TRUE;
+ 2571                                                t := SymTab.InvalidType
+ 2572                                             ELSIF NOT SymTab.FieldExists(t,
+ 2573                                                      fname) THEN
+ 2574                                               SemError(216);
+ 2575                                               t := SymTab.InvalidType
+ 2576                                              ELSE
+ 2577                                                t := SymTab.FieldType(t, fname);
+ 2578                                                sfx := TRUE
+ 2579                                              END; .)
+ 2580      | "^"                               (. isM := FALSE;
+ 2581                                             IF AST.Kind(node) # AST.NkDesignator THEN
+ 2582                                               astWrap := AST.MakeNode(
+ 2583                                                 AST.NkDesignator);
+ 2584                                               AST.SetChild(astWrap, 0, node);
+ 2585                                               node := astWrap
+ 2586                                             END;
+ 2587                                             astSel := AST.MakeNode(AST.NkSelector);
+ 2588                                             AST.SetOp(astSel, AST.SelDeref);
+ 2589                                             AST.SetChild(node,
+ 2590                                               AST.NChild(node), astSel); IF t = SymTab.InvalidType THEN
+ 2591                                             ELSIF SymTab.ClassOf(t) #
+ 2592                                                   SymTab.ClPtr THEN
+ 2593                                               SemError(219);
+ 2594                                               t := SymTab.InvalidType
+ 2595                                             ELSE
+ 2596                                               bt := SymTab.PtrBase(t);
+ 2597                                               IF bt # SymTab.InvalidType THEN
+ 2598                                                  t := bt; sfx := TRUE
+ 2599                                               END
+ 2600                                             END; .) .
+ 2601    Expr<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 2602                                          (. VAR t2: SymTab.TypeIndex;
+ 2603                                               op: INTEGER;
+ 2604                                               q2, qt, wl: QbeGen.QVal;
+ 2605                                                astA, astB: AST.Node;
+ 2606                                                astOp: INTEGER;
+ 2607                                                astMade: BOOLEAN;
+ 2608                                               isR: BOOLEAN; .)
+ 2609      = SimExpr<t, q>                     (. astA := astCur; astMade := FALSE; .)
+ 2610        [ Rel<op> SimExpr<t2, q2>
+ 2611          (. astB := astCur; astMade := TRUE;
+ 2612              astOp := AST.OpEq;
+ 2613              IF op = SymTab.OpNeq1 THEN astOp := AST.OpNe
+ 2614              ELSIF op = SymTab.OpNeq2 THEN astOp := AST.OpNe
+ 2615              ELSIF op = SymTab.OpLt THEN astOp := AST.OpLt
+ 2616              ELSIF op = SymTab.OpLe THEN astOp := AST.OpLe
+ 2617              ELSIF op = SymTab.OpGt THEN astOp := AST.OpGt
+ 2618              ELSIF op = SymTab.OpGe THEN astOp := AST.OpGe
+ 2619              ELSIF op = SymTab.OpIn THEN astOp := AST.OpIn
+ 2620              END;
+ 2621              IF op = SymTab.OpIn THEN
+ 2622               IF SymTab.InCheck(t, t2) THEN
+ 2623                 IF (t = SymTab.InvalidType)
+ 2624                    OR (t2 = SymTab.InvalidType) THEN
+ 2625                   t := SymTab.BoolType(); QbeGen.CopyOp("0", q)
+ 2626                 ELSE
+ 2627                    t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
+ 2628                 END
+ 2629               ELSE SemError(222); t := SymTab.InvalidType;
+ 2630                 QbeGen.CopyOp("0", q)
+ 2631               END
+ 2632             ELSIF SymTab.RelCheck(t, t2, op) THEN
+ 2633               IF (t = SymTab.InvalidType)
+ 2634                  OR (t2 = SymTab.InvalidType) THEN
+ 2635                 t := SymTab.BoolType(); QbeGen.CopyOp("0", q)
+ 2636               ELSIF (SymTab.ClassOf(t) = SymTab.ClPtr)
+ 2637                  OR (SymTab.ClassOf(t2) = SymTab.ClPtr) THEN
+ 2638                 IF (op # SymTab.OpEq) AND (op # SymTab.OpNeq1)
+ 2639   AND (op # SymTab.OpNeq2) THEN
+ 2640                   SemError(213); t := SymTab.InvalidType;
+ 2641                   QbeGen.CopyOp("0", q)
+ 2642                  ELSE
+ 2643                    t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
+ 2644                  END
+ 2645                ELSIF (SymTab.ClassOf(t) = SymTab.ClSet)
+ 2646                   OR (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
+ 2647                  t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
+ 2648               ELSIF SymTab.StrCompat(t, t2) THEN
+ 2649                 QbeGen.StrEq(op, q, q2, qt);
+ 2650                 t := SymTab.BoolType(); QbeGen.CopyOp(qt, q)
+ 2651               ELSIF SymTab.IsLongFamily(t)
+ 2652                  OR SymTab.IsLongFamily(t2) THEN
+ 2653                  t := SymTab.BoolType(); QbeGen.CopyOp("@", q)
+ 2654                ELSE
+ 2655                  t := SymTab.BoolType();
+ 2656                  QbeGen.CopyOp("@", q)
+ 2657                END
+ 2658             ELSE SemError(213); t := SymTab.InvalidType;
+ 2659                QbeGen.CopyOp("0", q)
+ 2660              END;
+ 2661              astCur := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB); .) ]
+ 2662         (. IF NOT astMade THEN astCur := astA END; .)
+ 2663             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
+ 2664    Rel<VAR op: INTEGER>
+ 2665      = "="                               (. op := SymTab.OpEq; .)
+ 2666      | "#"                               (. op := SymTab.OpNeq1; .)
+ 2667      | "<"                               (. op := SymTab.OpLt; .)
+ 2668      | "<="                              (. op := SymTab.OpLe; .)
+ 2669      | ">"                               (. op := SymTab.OpGt; .)
+ 2670      | ">="                              (. op := SymTab.OpGe; .)
+ 2671      | "IN"                              (. op := SymTab.OpIn; .) .
+ 2672    SimExpr<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 2673                                          (. VAR t2, res2, lt, rt:
+ 2674                                                 SymTab.TypeIndex;
+ 2675                                               op: INTEGER;
+ 2676                                               q2, qt, wq, qf, q2a, q2b:
+ 2677                                                 QbeGen.QVal;
+ 2678                                               neg, isR, isL, folded:
+ 2679                                                 BOOLEAN;
+ 2680                                               fok: BOOLEAN;
+ 2681                                               lw, rw, mw: CARDINAL;
+ 2682                                               lTrue, lNext, lDone, qr, qs: QbeGen.QVal;
+ 2683                                                astA, astB: AST.Node;
+ 2684                                                astSign, astOp: INTEGER; .)
+ 2685      =                                   (. neg := FALSE; astSign := 0; .)
+ 2686        [ "+"                         (. neg := TRUE; astSign := 1; .)
+ 2687        | "-"                         (. neg := TRUE; astSign := -1; .) ]
+ 2688        Term<t, q> (. astA := astCur;
+ 2689                                            IF neg AND QbeGen.IsImm(q) THEN
+ 2690                                              QbeGen.NegFold(q, q)
+ 2691                                            END;
+ 2692                                           IF astSign < 0 THEN
+ 2693                                             astCur := AST.MakeUn(
+ 2694                                               AST.NkUnary, AST.OpSub, astA);
+ 2695                                             astA := astCur
+ 2696                                           END; .)
+ 2697         { AddOp<op>
+ 2698           Term<t2, q2> (. astB := astCur; .)
+ 2699          (. astOp := AST.OpAdd;
+ 2700             IF op = SymTab.OpSub THEN astOp := AST.OpSub
+ 2701             ELSIF op = SymTab.OpOr THEN astOp := AST.OpOr END;
+ 2702             astA := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB);
+ 2703             astCur := astA;
+ 2704             IF op = SymTab.OpOr THEN
+ 2705               (* short-circuit: if q is true the RHS is skipped *)
+ 2706               IF SymTab.BoolCheck(t) AND SymTab.BoolCheck(t2) THEN
+ 2707                 t := SymTab.BoolType()
+ 2708               ELSE SemError(212); t := SymTab.InvalidType END;
+ 2709                IF t # SymTab.InvalidType THEN
+ 2710                  QbeGen.CopyOp("@", q)
+ 2711                ELSE QbeGen.CopyOp("0", q)
+ 2712                END
+ 2713             ELSIF (op = SymTab.OpAdd)
+ 2714               AND (SymTab.UStrCompat(t, t2)
+ 2715                 OR ((SymTab.ClassOf(t) = SymTab.ClUChar)
+ 2716                   AND (SymTab.ClassOf(t2) = SymTab.ClUStr))
+ 2717                 OR ((SymTab.ClassOf(t) = SymTab.ClUStr)
+ 2718                   AND (SymTab.ClassOf(t2) = SymTab.ClUChar))
+ 2719                 OR ((SymTab.ClassOf(t) = SymTab.ClUChar)
+ 2720                   AND (SymTab.ClassOf(t2) = SymTab.ClUChar))) THEN
+ 2721               (* UString concatenation: a UCHAR operand becomes a
+ 2722                  1-codepoint UString; the result is a descriptor in the
+ 2723                  shim's concat buffer.  Work on copies so neither
+ 2724                  operand is clobbered. *)
+ 2725                t := SymTab.NewUStr();
+ 2726                QbeGen.CopyOp("@", q)
+ 2727             ELSIF (op = SymTab.OpAdd)
+ 2728               AND (SymTab.StrCompat(t, t2)
+ 2729                 OR (SymTab.IsStrType(t)
+ 2730                   AND (SymTab.ClassOf(t2) = SymTab.ClChar))
+ 2731                 OR ((SymTab.ClassOf(t) = SymTab.ClChar)
+ 2732                   AND SymTab.IsStrType(t2))) THEN
+ 2733               (* string concatenation; a CHAR operand becomes a
+ 2734                  1-character string literal.  When both operands are
+ 2735                  constants, fold to a single string literal so a
+ 2736                  constructor element stays compile-time. *)
+ 2737                QbeGen.StrFold(q, q2, SymTab.ClassOf(t), SymTab.ClassOf(t2),
+ 2738                  qt, fok);
+ 2739                IF fok THEN QbeGen.CopyOp(qt, q)
+ 2740                ELSE QbeGen.CopyOp("@", q)
+ 2741                END;
+ 2742                t := SymTab.NewStr()
+ 2743             ELSIF (t # SymTab.InvalidType) AND (t2 # SymTab.InvalidType)
+ 2744   AND (SymTab.ClassOf(t) = SymTab.ClSet)
+ 2745   AND (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
+ 2746                lw := SymTab.SetWords(t); rw := SymTab.SetWords(t2);
+ 2747                mw := lw;
+ 2748                IF rw > mw THEN mw := rw END;
+ 2749                t := SymTab.NewSet(
+ 2750                       SymTab.NewSubR(0,
+ 2751                         VAL(INTEGER, mw) * 32 - 1));
+ 2752                QbeGen.CopyOp("@", q)
+ 2753             ELSE
+ 2754               IF SymTab.ArithCheck(t, t2, FALSE, res2) THEN
+ 2755                 lt := t; rt := t2; t := res2
+ 2756               ELSE SemError(211); t := SymTab.InvalidType END;
+ 2757               IF t # SymTab.InvalidType THEN
+ 2758                 isL := SymTab.IsLongFamily(t);
+ 2759                 isR := SymTab.ClassOf(t) = SymTab.ClReal;
+ 2760                 folded := FALSE;
+ 2761                 IF (NOT isL) AND (NOT isR)
+ 2762    AND QbeGen.IsImm(q) AND QbeGen.IsImm(q2) THEN
+ 2763                   IF op = SymTab.OpAdd THEN
+ 2764                     folded := QbeGen.Fold2(0, q, q2, qf)
+ 2765                   ELSE
+ 2766                     folded := QbeGen.Fold2(1, q, q2, qf)
+ 2767                   END
+ 2768                 END;
+ 2769                 IF folded THEN QbeGen.CopyOp(qf, q)
+ 2770                  ELSE
+ 2771                  QbeGen.CopyOp("@", q)
+ 2772                  END
+ 2773               ELSE QbeGen.CopyOp("0", q)
+ 2774               END
+ 2775             END; .) }
+ 2776             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
+ 2777    AddOp<VAR op: INTEGER>
+ 2778      = "+"                               (. op := SymTab.OpAdd; .)
+ 2779      | "-"                               (. op := SymTab.OpSub; .)
+ 2780      | "OR"                              (. op := SymTab.OpOr; .) .
+ 2781    Term<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 2782                                          (. VAR t2, res2, lt, rt:
+ 2783                                                 SymTab.TypeIndex;
+ 2784                                               op: INTEGER;
+ 2785                                               q2, qt, wq, qf:
+ 2786                                                 QbeGen.QVal;
+ 2787                                               isR, isL, folded: BOOLEAN;
+ 2788                                               lw, rw, mw: CARDINAL;
+ 2789                                               lNext, lFalse, lDone, qr, qs: QbeGen.QVal;
+ 2790                                                astA, astB: AST.Node;
+ 2791                                                astOp: INTEGER; .)
+ 2792      = Fact<t, q> (. astA := astCur; .) { MulOp<op>
+ 2793          Fact<t2, q2> (. astB := astCur; .)
+ 2794        (. astOp := AST.OpMul;
+ 2795           IF op = SymTab.OpSlash THEN astOp := AST.OpDiv
+ 2796           ELSIF op = SymTab.OpDiv THEN astOp := AST.OpDiv
+ 2797           ELSIF op = SymTab.OpMod THEN astOp := AST.OpMod
+ 2798           ELSIF op = SymTab.OpAnd THEN astOp := AST.OpAnd END;
+ 2799           astA := AST.MakeBin(AST.NkBinExpr, astOp, astA, astB);
+ 2800           astCur := astA;
+ 2801           IF op = SymTab.OpAnd THEN
+ 2802             (* short-circuit: if q is false the RHS is skipped *)
+ 2803             IF SymTab.BoolCheck(t) AND SymTab.BoolCheck(t2) THEN
+ 2804               t := SymTab.BoolType()
+ 2805             ELSE SemError(212); t := SymTab.InvalidType END;
+ 2806              IF t # SymTab.InvalidType THEN QbeGen.CopyOp("@", q)
+ 2807              ELSE QbeGen.CopyOp("0", q)
+ 2808              END
+ 2809           ELSIF (t # SymTab.InvalidType) AND (t2 # SymTab.InvalidType)
+ 2810   AND (SymTab.ClassOf(t) = SymTab.ClSet)
+ 2811   AND (SymTab.ClassOf(t2) = SymTab.ClSet) THEN
+ 2812              lw := SymTab.SetWords(t); rw := SymTab.SetWords(t2);
+ 2813              mw := lw;
+ 2814              IF rw > mw THEN mw := rw END;
+ 2815              t := SymTab.NewSet(
+ 2816                     SymTab.NewSubR(0,
+ 2817                       VAL(INTEGER, mw) * 32 - 1));
+ 2818              QbeGen.CopyOp("@", q)
+ 2819           ELSE
+ 2820             IF SymTab.ArithCheck(t, t2,
+ 2821                  (op = SymTab.OpDiv) OR (op = SymTab.OpMod),
+ 2822                  res2) THEN
+ 2823               lt := t; rt := t2; t := res2
+ 2824             ELSE SemError(211); t := SymTab.InvalidType END;
+ 2825             IF t # SymTab.InvalidType THEN
+ 2826               isL := SymTab.IsLongFamily(t);
+ 2827               isR := SymTab.ClassOf(t) = SymTab.ClReal;
+ 2828               folded := FALSE;
+ 2829               IF (NOT isL) AND (NOT isR)
+ 2830    AND QbeGen.IsImm(q) AND QbeGen.IsImm(q2) THEN
+ 2831                 IF op = SymTab.OpTimes THEN
+ 2832                   folded := QbeGen.Fold2(2, q, q2, qf)
+ 2833                 ELSIF op = SymTab.OpDiv THEN
+ 2834                   folded := QbeGen.Fold2(3, q, q2, qf)
+ 2835                 ELSIF op = SymTab.OpMod THEN
+ 2836                   folded := QbeGen.Fold2(4, q, q2, qf)
+ 2837                 END
+ 2838               END;
+ 2839               IF folded THEN QbeGen.CopyOp(qf, q)
+ 2840                ELSE
+ 2841                QbeGen.CopyOp("@", q)
+ 2842                END
+ 2843             ELSE QbeGen.CopyOp("0", q)
+ 2844             END
+ 2845           END; .) }
+ 2846             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
+ 2847    MulOp<VAR op: INTEGER>
+ 2848      = "*"                               (. op := SymTab.OpTimes; .)
+ 2849      | "/"                               (. op := SymTab.OpSlash; .)
+ 2850      | "DIV"                             (. op := SymTab.OpDiv; .)
+ 2851      | "MOD"                             (. op := SymTab.OpMod; .)
+ 2852      | ( "AND" | "&" )                   (. op := SymTab.OpAnd; .) .
+ 2853    Fact<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 2854                                          (. VAR s: ARRAY [0 .. 255] OF CHAR;
+ 2855                                               et, dt, t2, st, ct2, et2:
+ 2856                                                 SymTab.TypeIndex;
+ 2857                                               dk: INTEGER;
+ 2858                                               qd, q2, sq, qa, qm0, qr, qt:
+ 2859                                                 QbeGen.QVal;
+ 2860                                               qn, vn: SymTab.Name;
+ 2861                                               vt: SymTab.TypeIndex;
+ 2862                                               c1, c2: INTEGER;
+ 2863                                               lo, hi: INTEGER;
+ 2864                                               isMax: BOOLEAN;
+ 2865                                               called, isHigh, sfx, isCh,
+ 2866                                               isU, uok, isStr: BOOLEAN;
+ 2867                                               ucp: INTEGER; astIsLit: BOOLEAN;
+ 2868                                                astD: AST.Node;
+ 2869                                                astCall: BOOLEAN;
+ 2870                                                astNode, astNot: AST.Node;
+ 2871                                                j: CARDINAL;
+ 2872                                                astArg2: AST.Node;
+ 2873                                                astBrace: AST.Node;
+ 2874                                                astRes: AST.Node; mname: SymTab.Name; isM: BOOLEAN; .)
+ 2875      = (. astIsLit := FALSE; .)
+ 2876      ( integer                           (. LexString(s);
+ 2877                                             QbeGen.NormInt(s, q); IF twoPhase THEN astIsLit := TRUE; astCur := AST.MakeLeaf(AST.NkIntLit, s) END;
+ 2878                                             t := SymTab.IntType(); .)
+ 2879      | charConst                         (. LexString(s);
+ 2880                                             QbeGen.NormLit(s, q, isCh);
+ 2881                                             IF twoPhase THEN
+ 2882                                               astIsLit := TRUE;
+ 2883                                               astCur := AST.MakeLeaf(
+ 2884                                                 AST.NkCharLit, s)
+ 2885                                             END;
+ 2886                                             t := SymTab.CharType(); .)
+ 2887      | real                              (. LexString(s);
+ 2888                                             QbeGen.NormReal(s, q);
+ 2889                                             IF twoPhase THEN
+ 2890                                               astIsLit := TRUE;
+ 2891                                               astCur := AST.MakeLeaf(
+ 2892                                                 AST.NkRealLit, s)
+ 2893                                             END;
+ 2894                                             t := SymTab.RealType(); .)
+ 2895      | string                            (. LexString(s);
+ 2896                                             IF twoPhase THEN
+ 2897                                               astIsLit := TRUE;
+ 2898                                               astCur := AST.MakeLeaf(
+ 2899                                                 AST.NkStrLit, s)
+ 2900                                             END;
+ 2901                                             IF SymTab.StrLen(s) = 3 THEN
+ 2902                                               t := SymTab.CharType();
+ 2903                                               QbeGen.IntStr(
+ 2904                                                 QbeGen.CharVal(s), q)
+ 2905                                             ELSE t := SymTab.NewStr();
+ 2906                                               QbeGen.DeclStr(s, q);
+ 2907                                               (* a literal's value IS its
+ 2908                                                  static descriptor address *)
+ 2909                                             END; .)
+ 2910      | ustring                           (. LexString(s);
+ 2911                                             IF twoPhase THEN
+ 2912                                               astIsLit := TRUE;
+ 2913                                               astCur := AST.MakeLeaf(
+ 2914                                                 AST.NkStrLit, s)
+ 2915                                             END;
+ 2916                                             QbeGen.DeclUStr(s, q, isU, ucp,
+ 2917                                               uok);
+ 2918                                             IF NOT uok THEN
+ 2919                                               SemError(234);
+ 2920                                               t := SymTab.InvalidType
+ 2921                                             ELSIF isU THEN
+ 2922                                               t := SymTab.UCharType();
+ 2923                                               QbeGen.IntStr(ucp, q)
+ 2924                                             ELSE
+ 2925                                               t := SymTab.NewUStr();
+ 2926                                             END; .)
+ 2927      | Design<dt, dk, qd, qn, sfx>       (. astD := astCur; astCall := FALSE; astBrace := AST.NoNode;
+ 2928                                             astNArgs := 0; called := FALSE;
+ 2929                                             t := dt;
+ 2930                                             IF dk = SymTab.KindConst THEN
+ 2931                                               QbeGen.CopyOp(qd, q)
+ 2932                                             ELSE QbeGen.CopyOp("@", q)
+ 2933                                             END; .)
+ 2934        [ TypedBraceLit<dt, q>            (. t := dt; astCall := TRUE;
+ 2935                                               astBrace := astCur; .) ]
+ 2936        [ ArgList<qn, dt, qd, TRUE, FALSE, methCls, ct2, q2, called>
+ 2937                                          (. astCall := TRUE;
+ 2938                                             astNode := AstCallNode(astD);
+ 2939                                             astRes := astNode;
+ 2940                                             t := ct2;
+ 2941                                             QbeGen.CopyOp(q2, q);
+ 2942                                             sfx := FALSE; .)
+ 2943          { ResultComp<t, q, sfx, astRes, mname, methCls, isM>
+ 2944            [ (. astNArgs := 0; .)
+ 2945              ArgList<mname, t, q, TRUE, FALSE, methCls, ct2, q2, called>
+ 2946                                          (. astNode := AstCallNode(astRes);
+ 2947                                             astRes := astNode;
+ 2948                                             t := ct2;
+ 2949                                             QbeGen.CopyOp(q2, q);
+ 2950                                             sfx := FALSE; .) ] }
+ 2951                                          (. IF sfx THEN
+ 2952                                               IF t = SymTab.InvalidType THEN
+ 2953                                                 QbeGen.CopyOp("0", q)
+ 2954                                               ELSIF (SymTab.ClassOf(t) #
+ 2955                                                      SymTab.ClRecord)
+ 2956    AND (SymTab.ClassOf(t) # SymTab.ClSet)
+ 2957    AND (SymTab.ClassOf(t) # SymTab.ClArray)
+ 2958    AND (SymTab.ClassOf(t) # SymTab.ClClass) THEN
+ 2959                                                  QbeGen.CopyOp("@", q)
+ 2960                                               END
+ 2961                                             END; .) ]
+ 2962                                          (. IF called THEN
+ 2963                                               astCur := astRes
+ 2964                                             ELSIF astCall THEN
+ 2965                                               astCur := astBrace
+ 2966                                             ELSE astCur := astD
+ 2967                                             END;
+ 2968                                              astIsLit := TRUE;
+ 2969                                              IF NOT called
+ 2970   AND (dk = SymTab.KindProc) THEN
+ 2971                                               (* bare zero-arg function
+ 2972                                                  call (parentheses may be
+ 2973                                                  omitted); a proper or
+ 2974                                                  parameterised proc here
+ 2975                                                  is 230 *)
+ 2976                                                IF (SymTab.ProcNPar(qn) = 0)
+ 2977   AND (SymTab.ProcRes(qn) # SymTab.InvalidType) THEN
+ 2978                                                  t := SymTab.ProcRes(qn);
+ 2979                                                  QbeGen.CopyOp("@", q);
+ 2980                                                  astCur := AST.MakeNode(AST.NkCall);
+ 2981                                                  AST.SetChild(astCur, 0, astD)
+ 2982                                                ELSE
+ 2983                                                  t := SymTab.ProcTypeOf(qn);
+ 2984                                                  QbeGen.CopyOp("@", q)
+ 2985                                                END
+ 2986                                             END; .)
+ 2987      | ( "HIGH"                          (. isHigh := TRUE; .)
+ 2988        | ( "LEN" | "LENGTH" )            (. isHigh := FALSE; .) )
+ 2989        "(" ( Design<dt, dk, qd, qn, sfx> (. isStr := FALSE;
+ 2990                                              isU := FALSE; .)
+ 2991            | string                       (. LexString(s); astCur := AST.MakeLeaf(AST.NkStrLit, s);
+ 2992                                              isStr := TRUE;
+ 2993                                              isU := FALSE;
+ 2994                                              IF SymTab.StrLen(s) = 3 THEN
+ 2995                                                dt := SymTab.CharType();
+ 2996                                                QbeGen.IntStr(QbeGen.CharVal(s),
+ 2997                                                  qd)
+ 2998                                              ELSE
+ 2999                                                dt := SymTab.NewStr();
+ 3000                                                QbeGen.DeclStr(s, qd);
+ 3001                                              END;
+ 3002                                              dk := -1;
+ 3003                                              qn[0] := CHR(0); .)
+ 3004            | ustring                      (. LexString(s); astCur := AST.MakeLeaf(AST.NkStrLit, s);
+ 3005                                              QbeGen.DeclUStr(s, qd, isU, ucp,
+ 3006                                                uok);
+ 3007                                              isStr := FALSE;
+ 3008                                              IF NOT uok THEN
+ 3009                                                SemError(234);
+ 3010                                                dt := SymTab.InvalidType
+ 3011                                              ELSIF isU THEN
+ 3012                                                (* one codepoint: a UCHAR;
+ 3013                                                   LEN is 1, HIGH is 0 *)
+ 3014                                                dt := SymTab.UCharType();
+ 3015                                                QbeGen.IntStr(ucp, qd)
+ 3016                                              ELSE
+ 3017                                                dt := SymTab.NewUStr();
+ 3018                                              END;
+ 3019                                              dk := -1;
+ 3020                                              qn[0] := CHR(0); .) )
+ 3021        ")"
+ 3022                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 3023     IF isHigh THEN AST.SetChild(astNode, 0,
+ 3024       AST.MakeLeaf(AST.NkIdent, "HIGH"))
+ 3025     ELSE AST.SetChild(astNode, 0,
+ 3026       AST.MakeLeaf(AST.NkIdent, "LEN")) END;
+ 3027     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3028     astCur := astNode; astIsLit := TRUE;
+ 3029                                             IF (dt # SymTab.InvalidType)
+ 3030    AND (SymTab.ClassOf(dt) = SymTab.ClUStr) THEN
+ 3031                                               (* UString: the count is
+ 3032                                                  the descriptor header *)
+ 3033                                                t := SymTab.IntType();
+ 3034                                                QbeGen.CopyOp("@", q)
+ 3035                                             ELSIF (dt # SymTab.InvalidType)
+ 3036    AND (SymTab.ClassOf(dt) = SymTab.ClUChar) THEN
+ 3037                                               (* single UCHAR codepoint *)
+ 3038                                               IF isHigh THEN
+ 3039                                                 QbeGen.CopyOp("0", qr)
+ 3040                                               ELSE
+ 3041                                                 QbeGen.CopyOp("1", qr)
+ 3042                                               END;
+ 3043                                               t := SymTab.IntType();
+ 3044                                               QbeGen.CopyOp(qr, q)
+ 3045                                             ELSIF isStr THEN
+ 3046                                               (* fold: content length at
+ 3047                                                  compile time *)
+ 3048                                               IF SymTab.StrLen(s) = 3 THEN
+ 3049                                                 c1 := 1
+ 3050                                               ELSE
+ 3051                                                 c1 :=
+ 3052                                                   SymTab.StrLen(s) - 2
+ 3053                                               END;
+ 3054                                               IF isHigh THEN
+ 3055                                                 DEC(c1)
+ 3056                                               END;
+ 3057                                               QbeGen.IntStr(c1, qr);
+ 3058                                               t := SymTab.IntType();
+ 3059                                               QbeGen.CopyOp(qr, q)
+ 3060                                             ELSIF dt = SymTab.InvalidType THEN
+ 3061                                               t := SymTab.InvalidType;
+ 3062                                               QbeGen.CopyOp("0", q)
+ 3063                                             ELSIF SymTab.ClassOf(dt) #
+ 3064                                                   SymTab.ClArray THEN
+ 3065                                               SemError(217);
+ 3066                                               t := SymTab.InvalidType;
+ 3067                                               QbeGen.CopyOp("0", q)
+ 3068                                             ELSE
+ 3069                                                IF SymTab.IsOpenArray(dt) THEN
+ 3070                                                  t := SymTab.IntType();
+ 3071                                                  QbeGen.CopyOp("@", q)
+ 3072                                                ELSE
+ 3073                                                  IF isHigh THEN
+ 3074                                                    QbeGen.IntStr(
+ 3075                                                      SymTab.ArrayHi(dt), qr)
+ 3076                                                  ELSE
+ 3077                                                    QbeGen.IntStr(VAL(
+ 3078                                                      INTEGER,
+ 3079                                                      SymTab.ArrayLen(dt)),
+ 3080                                                      qr)
+ 3081                                                  END;
+ 3082                                                  t := SymTab.IntType();
+ 3083                                                  QbeGen.CopyOp(qr, q)
+ 3084                                                END
+ 3085                                              END; .)
+ 3086      | ( "SIZE" | "TSIZE" ) "(" Design<dt, dk, qd, qn, sfx> ")"
+ 3087      (. astNode := AST.MakeNode(AST.NkCall);
+ 3088     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "SIZE"));
+ 3089     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3090     astCur := astNode; astIsLit := TRUE; .)
+ 3091                                          (. IF dt = SymTab.InvalidType THEN
+ 3092                                               t := SymTab.InvalidType;
+ 3093                                               QbeGen.CopyOp("0", q)
+ 3094                                             ELSE
+ 3095                                               QbeGen.IntStr(VAL(INTEGER,
+ 3096                                                 SymTab.ObjectSize(dt)), q);
+ 3097                                               t := SymTab.IntType()
+ 3098                                             END; .)
+ 3099      | ( "SHIFT"                         (. isMax := FALSE; .)
+ 3100        | "ROTATE"                        (. isMax := TRUE; .) )
+ 3101        "(" Expr<et, q> (. astArg2 := astCur; .) "," Expr<et2, q2> ")"
+ 3102                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 3103     IF isMax THEN AST.SetChild(astNode, 0,
+ 3104       AST.MakeLeaf(AST.NkIdent, "ROTATE"))
+ 3105     ELSE AST.SetChild(astNode, 0,
+ 3106       AST.MakeLeaf(AST.NkIdent, "SHIFT")) END;
+ 3107     IF astArg2 # AST.NoNode THEN AST.SetChild(astNode, 1, astArg2) END;
+ 3108     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 2, astCur) END;
+ 3109     astCur := astNode; astIsLit := TRUE;
+ 3110                                             (* set shift/rotate: isMax
+ 3111                                                doubles as "rotate" *)
+ 3112                                             IF (et # SymTab.InvalidType)
+ 3113                                                AND (SymTab.ClassOf(et) =
+ 3114                                                   SymTab.ClSet) THEN
+ 3115                                                t := et;
+ 3116                                                QbeGen.CopyOp("@", q)
+ 3117                                             ELSE SemError(230);
+ 3118                                               t := SymTab.InvalidType;
+ 3119                                               QbeGen.CopyOp("0", q)
+ 3120                                             END; .)
+ 3121      | ( "MIN"                           (. isMax := FALSE; .)
+ 3122        | "MAX"                           (. isMax := TRUE; .) )
+ 3123        "(" Design<dt, dk, qd, qn, sfx> ")"
+ 3124                                          (. astNode := AST.MakeNode(AST.NkCall);
+ 3125     IF isMax THEN AST.SetChild(astNode, 0,
+ 3126       AST.MakeLeaf(AST.NkIdent, "MAX"))
+ 3127     ELSE AST.SetChild(astNode, 0,
+ 3128       AST.MakeLeaf(AST.NkIdent, "MIN")) END;
+ 3129     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3130     astCur := astNode; astIsLit := TRUE;
+ 3131                                             IF (dt # SymTab.InvalidType)
+ 3132   AND (SymTab.ClassOf(dt) = SymTab.ClReal) THEN
+ 3133                                               (* REAL/LONGREAL: the
+ 3134                                                  implementation bounds *)
+ 3135                                               IF isMax THEN
+ 3136                                                 QbeGen.NormReal(
+ 3137                                                   "3.402823e38", q)
+ 3138                                               ELSE QbeGen.NormReal(
+ 3139                                                   "-3.402823e38", q)
+ 3140                                               END;
+ 3141                                               t := SymTab.RealType()
+ 3142                                             ELSIF (dt #
+ 3143                                                SymTab.InvalidType)
+ 3144   AND (SymTab.ClassOf(dt) =
+ 3145                                                   SymTab.ClLong) THEN
+ 3146                                               IF isMax THEN
+ 3147                                                 QbeGen.CopyOp(
+ 3148                                                   "9223372036854775807", q)
+ 3149                                               ELSE QbeGen.CopyOp(
+ 3150                                                   "-9223372036854775808", q)
+ 3151                                               END;
+ 3152                                               t := SymTab.LongType()
+ 3153                                             ELSIF SymTab.TypeBounds(dt, lo,
+ 3154                                                      hi) THEN
+ 3155                                               IF isMax THEN
+ 3156                                                 QbeGen.IntStr(hi, q)
+ 3157                                               ELSE QbeGen.IntStr(lo, q)
+ 3158                                               END;
+ 3159                                               t := SymTab.IntType()
+ 3160                                             ELSE SemError(230);
+ 3161                                               t := SymTab.InvalidType;
+ 3162                                               QbeGen.CopyOp("0", q)
+ 3163                                             END; .)
+ 3164      | "ADR" "(" Design<dt, dk, qd, qn, sfx> ")"
+ 3165      (. astNode := AST.MakeNode(AST.NkCall);
+ 3166     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ADR"));
+ 3167     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3168     astCur := astNode; astIsLit := TRUE; .)
+ 3169                                          (. IF dt = SymTab.InvalidType THEN
+ 3170                                               t := SymTab.InvalidType;
+ 3171                                               QbeGen.CopyOp("0", q)
+ 3172                                             ELSE
+ 3173                                                IF sfx
+ 3174                                                   OR (dk = SymTab.KindVar)
+ 3175                                                   OR (dk = SymTab.KindParam) THEN
+ 3176                                                  QbeGen.CopyOp("@", q)
+ 3177                                                ELSE SemError(230);
+ 3178                                                  QbeGen.CopyOp("0", q)
+ 3179                                                END;
+ 3180                                               t := SymTab.AddrType()
+ 3181                                             END; .)
+ 3182      | "CHR" "(" Expr<et, q> ")"
+ 3183      (. astNode := AST.MakeNode(AST.NkCall);
+ 3184     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CHR"));
+ 3185     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3186     astCur := astNode; astIsLit := TRUE; .)
+ 3187                                          (. IF (et # SymTab.InvalidType)
+ 3188   AND NOT SymTab.IsIntFamily(et) THEN
+ 3189                                               SemError(211) END;
+ 3190                                             t := SymTab.CharType(); .)
+ 3191      | ( "ORD" | "ORDL" ) "(" Expr<et, q> ")"
+ 3192      (. astNode := AST.MakeNode(AST.NkCall);
+ 3193     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ORD"));
+ 3194     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3195     astCur := astNode; astIsLit := TRUE; .)
+ 3196                                          (. IF et # SymTab.InvalidType THEN
+ 3197                                               IF (SymTab.ClassOf(et) #
+ 3198                                                   SymTab.ClChar)
+ 3199   AND (SymTab.ClassOf(et) #
+ 3200                                                     SymTab.ClBool)
+ 3201   AND (SymTab.ClassOf(et) #
+ 3202                                                     SymTab.ClEnum)
+ 3203   AND NOT SymTab.IsIntFamily(et) THEN
+ 3204                                                 SemError(211) END
+ 3205                                             END;
+ 3206                                             t := SymTab.IntType(); .)
+ 3207      | "CAP" "(" Expr<et, q> ")"
+ 3208      (. astNode := AST.MakeNode(AST.NkCall);
+ 3209     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CAP"));
+ 3210     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3211     astCur := astNode; astIsLit := TRUE; .)
+ 3212                                           (. QbeGen.CopyOp("@", q);
+ 3213                                             t := SymTab.CharType(); .)
+ 3214      | "UCHR" "(" Expr<et, q> ")"
  3215      (. astNode := AST.MakeNode(AST.NkCall);
- 3216     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ABS"));
+ 3216     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "UCHR"));
  3217     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
  3218     astCur := astNode; astIsLit := TRUE; .)
- 3219                                          (. IF (et # SymTab.InvalidType)
- 3220   AND NOT SymTab.IsIntFamily(et)
- 3221   AND (SymTab.ClassOf(et) #
- 3222                                                  SymTab.ClReal) THEN
- 3223                                               SemError(211)
- 3224                                              ELSE QbeGen.CopyOp("@", q)
- 3225                                             END;
- 3226                                             t := et; .)
- 3227      | "VAL" "(" GetIdent<vn> (. astArg2 := AST.MakeLeaf(AST.NkIdent, vn); .) "," Expr<et, q> ")"
- 3228      (. astNode := AST.MakeNode(AST.NkCall);
- 3229     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "VAL"));
- 3230     IF astArg2 # AST.NoNode THEN AST.SetChild(astNode, 1, astArg2) END;
- 3231     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 2, astCur) END;
+ 3219                                          (. (* UCHR: the UCHAR constructor.
+ 3220                                                CHAR -> UCHAR (identity);
+ 3221                                                INTEGER familly -> UCHAR
+ 3222                                                (codepoint value). *)
+ 3223                                             IF (et # SymTab.InvalidType)
+ 3224    AND (SymTab.ClassOf(et) # SymTab.ClChar)
+ 3225    AND NOT SymTab.IsIntFamily(et) THEN
+ 3226                                               SemError(211) END;
+ 3227                                             t := SymTab.UCharType(); .)
+ 3228      | "CHR8" "(" Expr<et, q> ")"
+ 3229      (. astNode := AST.MakeNode(AST.NkCall);
+ 3230     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "CHR8"));
+ 3231     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
  3232     astCur := astNode; astIsLit := TRUE; .)
- 3233                                          (. IF NOT SymTab.Lookup(vn) THEN
- 3234                                               SemError(201);
- 3235                                               t := SymTab.InvalidType
- 3236                                             ELSE vt := SymTab.SymType(vn);
- 3237                                               IF vt = SymTab.InvalidType THEN
- 3238                                                 t := SymTab.InvalidType
- 3239                                               ELSIF et =
- 3240                                                  SymTab.InvalidType THEN
- 3241                                                 t := vt
- 3242                                               ELSE
- 3243                                                 c1 := SymTab.ClassOf(et);
- 3244                                                 c2 := SymTab.ClassOf(vt);
- 3245                                                 IF (c1 = SymTab.ClInt)
- 3246    AND (c2 = SymTab.ClLong) THEN
- 3247                                                   QbeGen.WidenLong(q, qa);
- 3248                                                   QbeGen.CopyOp(qa, q);
- 3249                                                   t := vt
- 3250                                                 ELSIF (c1 = SymTab.ClLong)
- 3251    AND (c2 = SymTab.ClInt) THEN
- 3252                                                   QbeGen.NarrowLong(q, qa);
- 3253                                                   QbeGen.CopyOp(qa, q);
- 3254                                                   t := vt
- 3255                                                 ELSIF (c1 = SymTab.ClInt)
- 3256    AND (c2 = SymTab.ClReal) THEN
- 3257                                                   QbeGen.ConvIR(q, qa);
- 3258                                                   QbeGen.CopyOp(qa, q);
- 3259                                                   t := vt
- 3260                                                 ELSIF (c1 = SymTab.ClLong)
- 3261    AND (c2 = SymTab.ClReal) THEN
- 3262                                                   QbeGen.ConvLR(q, qa);
- 3263                                                   QbeGen.CopyOp(qa, q);
- 3264                                                   t := vt
- 3265                                                 ELSIF (c1 = SymTab.ClReal)
- 3266    AND (c2 = SymTab.ClInt) THEN
- 3267                                                   QbeGen.ConvRI(q, qa);
- 3268                                                   QbeGen.CopyOp(qa, q);
- 3269                                                   t := vt
- 3270                                                 ELSIF (c1 = SymTab.ClReal)
- 3271    AND (c2 = SymTab.ClLong) THEN
- 3272                                                   QbeGen.ConvRL(q, qa);
- 3273                                                   QbeGen.CopyOp(qa, q);
- 3274                                                   t := vt
- 3275                                                 ELSIF ((c1 = SymTab.ClInt)
- 3276                                                     OR (c1 =
- 3277                                                        SymTab.ClChar)
- 3278                                                     OR (c1 =
- 3279                                                        SymTab.ClBool)
- 3280                                                     OR (c1 =
- 3281                                                        SymTab.ClEnum))
- 3282   AND ((c2 = SymTab.ClInt)
- 3283                                                     OR (c2 =
- 3284                                                        SymTab.ClChar)
- 3285                                                     OR (c2 =
- 3286                                                        SymTab.ClBool)
- 3287                                                     OR (c2 =
- 3288                                                        SymTab.ClEnum)) THEN
+ 3233                                          (. IF (et # SymTab.InvalidType)
+ 3234    AND (SymTab.ClassOf(et) # SymTab.ClUChar) THEN
+ 3235                                               SemError(211) END;
+ 3236                                             t := SymTab.CharType(); .)
+ 3237      | "UORD" "(" Expr<et, q> ")"
+ 3238      (. astNode := AST.MakeNode(AST.NkCall);
+ 3239     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "UORD"));
+ 3240     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3241     astCur := astNode; astIsLit := TRUE; .)
+ 3242                                          (. (* UORD(u): the codepoint as a
+ 3243                                                32-bit ordinal (INTEGER),
+ 3244                                                cf. ORD for CHAR. *)
+ 3245                                             IF (et # SymTab.InvalidType)
+ 3246    AND (SymTab.ClassOf(et) # SymTab.ClUChar) THEN
+ 3247                                               SemError(211) END;
+ 3248                                             t := SymTab.IntType(); .)
+ 3249      | "ABS" "(" Expr<et, q> ")"
+ 3250      (. astNode := AST.MakeNode(AST.NkCall);
+ 3251     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "ABS"));
+ 3252     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 1, astCur) END;
+ 3253     astCur := astNode; astIsLit := TRUE; .)
+ 3254                                          (. IF (et # SymTab.InvalidType)
+ 3255   AND NOT SymTab.IsIntFamily(et)
+ 3256   AND (SymTab.ClassOf(et) #
+ 3257                                                  SymTab.ClReal) THEN
+ 3258                                               SemError(211)
+ 3259                                              ELSE QbeGen.CopyOp("@", q)
+ 3260                                             END;
+ 3261                                             t := et; .)
+ 3262      | "VAL" "(" GetIdent<vn> (. astArg2 := AST.MakeLeaf(AST.NkIdent, vn); .) "," Expr<et, q> ")"
+ 3263      (. astNode := AST.MakeNode(AST.NkCall);
+ 3264     AST.SetChild(astNode, 0, AST.MakeLeaf(AST.NkIdent, "VAL"));
+ 3265     IF astArg2 # AST.NoNode THEN AST.SetChild(astNode, 1, astArg2) END;
+ 3266     IF astCur # AST.NoNode THEN AST.SetChild(astNode, 2, astCur) END;
+ 3267     astCur := astNode; astIsLit := TRUE; .)
+ 3268                                          (. IF NOT SymTab.Lookup(vn) THEN
+ 3269                                               SemError(201);
+ 3270                                               t := SymTab.InvalidType
+ 3271                                             ELSE vt := SymTab.SymType(vn);
+ 3272                                               IF vt = SymTab.InvalidType THEN
+ 3273                                                 t := SymTab.InvalidType
+ 3274                                               ELSIF et =
+ 3275                                                  SymTab.InvalidType THEN
+ 3276                                                 t := vt
+ 3277                                               ELSE
+ 3278                                                 c1 := SymTab.ClassOf(et);
+ 3279                                                 c2 := SymTab.ClassOf(vt);
+ 3280                                                 IF (c1 = SymTab.ClInt)
+ 3281    AND (c2 = SymTab.ClLong) THEN
+ 3282                                                   QbeGen.WidenLong(q, qa);
+ 3283                                                   QbeGen.CopyOp(qa, q);
+ 3284                                                   t := vt
+ 3285                                                 ELSIF (c1 = SymTab.ClLong)
+ 3286    AND (c2 = SymTab.ClInt) THEN
+ 3287                                                   QbeGen.NarrowLong(q, qa);
+ 3288                                                   QbeGen.CopyOp(qa, q);
  3289                                                   t := vt
- 3290                                                 ELSIF (c1 = SymTab.ClPtr)
- 3291   AND (c2 = SymTab.ClPtr) THEN
- 3292                                                   t := vt
- 3293                                                 ELSIF (c1 = SymTab.ClReal)
- 3294   AND (c2 = SymTab.ClReal) THEN
- 3295                                                   t := vt
- 3296                                                 ELSE SemError(230);
- 3297                                                   t := SymTab.InvalidType
- 3298                                                 END
- 3299                                               END
- 3300                                             END; .)
- 3301      | "(" Expr<et, q> ")"               (. t := et; astIsLit := TRUE; .)
- 3302      | SetLit<st, sq>                    (. astIsLit := TRUE; t := st;
- 3303                                             QbeGen.CopyOp(sq, q); .)
- 3304      | ( "NOT" | "~" ) Fact<t2, q2>      (. astNot := astCur;
- 3305                                             IF SymTab.BoolCheck(t2) THEN
- 3306                                               t := SymTab.BoolType()
- 3307                                             ELSE SemError(212);
- 3308                                               t := SymTab.InvalidType END;
- 3309                                             IF t # SymTab.InvalidType THEN
- 3310                                                QbeGen.CopyOp("@", q)
- 3311                                             ELSE QbeGen.CopyOp("0", q)
- 3312                                             END;
- 3313                                             astIsLit := TRUE;
- 3314                                             astCur := AST.MakeUn(
- 3315                                               AST.NkUnary, AST.OpNot, astNot); .)
- 3316      )
- 3317      (. IF NOT astIsLit THEN astCur := AST.NoNode END; .)
- 3318             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
- 3319    (* Set literals are SET OF [0..255] (8 words); elements validated
- 3320       0..255 statically when foldable (222 otherwise), runtime trap
- 3321       for computed elements. Ranges always lower via SetRange. *)
- 3322    SetLit<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 3323                                          (. VAR astNode: AST.Node; .)
- 3324      = "{"                               (. t := SymTab.NewSet(
- 3325                                               SymTab.NewSubR(0, 255));
- 3326                                             astNode := AST.MakeNode(AST.NkSetLit);
- 3327                                             QbeGen.NewSetTemp(8, q);
- 3328                                             QbeGen.SetZero(q, 8); .)
- 3329        [ SetElem<t, q, astNode> { "," SetElem<t, q, astNode> } ]
- 3330        "}"                               (. astCur := astNode; .) .
- 3331    (* Typed brace constructor: TypeName{ elems } — BITSET{0} (a set)
- 3332       or ArrayName{...} (an array constructor, GNU Modula-2).  The
- 3333       declared type sets the width (set) or element type (array). *)
- 3334    TypedBraceLit<vt: SymTab.TypeIndex; VAR q: QbeGen.QVal>
- 3335                                          (. VAR nw: CARDINAL;
- 3336                                               astNode, astTail: AST.Node;
- 3337                                               savedCls: INTEGER; .)
- 3338      = "{"                               (. savedCls := braceCls;
- 3339                                             astNode := AST.MakeNode(AST.NkBraceLit);
- 3340                                             AST.SetTy(astNode, vt);
- 3341                                             astTail := astNode;
- 3342                                             IF vt = SymTab.InvalidType THEN
- 3343                                               braceCls := -1
- 3344                                             ELSE braceCls :=
- 3345                                                    SymTab.ClassOf(vt)
- 3346                                             END;
- 3347                                             IF braceCls = SymTab.ClSet THEN
- 3348                                               IF vt = SymTab.InvalidType THEN
- 3349                                                 nw := 8
- 3350                                               ELSE nw := SymTab.SetWords(vt);
- 3351                                                 IF nw = 0 THEN nw := 8 END
- 3352                                               END;
- 3353                                               QbeGen.NewSetTemp(nw, q);
- 3354                                               QbeGen.SetZero(q, nw)
- 3355                                             ELSIF (braceCls =
- 3356                                                    SymTab.ClArray)
- 3357                                                OR (braceCls =
- 3358                                                    SymTab.ClRecord)
- 3359                                                OR (braceCls =
- 3360                                                    SymTab.ClClass) THEN
- 3361                                               QbeGen.CtorBegin(vt)
- 3362                                             ELSE
- 3363                                               IF vt # SymTab.InvalidType THEN
- 3364                                                 SemError(230) END;
- 3365                                               braceCls := -1
- 3366                                             END; .)
- 3367        [ BraceElem<vt, q, astNode, astTail>
- 3368          { "," BraceElem<vt, q, astNode, astTail> } ]
- 3369        "}"                               (. IF (braceCls = SymTab.ClArray)
- 3370                                                OR (braceCls =
- 3371                                                   SymTab.ClRecord)
- 3372                                                OR (braceCls =
- 3373                                                   SymTab.ClClass) THEN
- 3374                                               QbeGen.CtorEnd(q)
- 3375                                             ELSIF braceCls # SymTab.ClSet THEN
- 3376                                               QbeGen.CopyOp("0", q)
- 3377                                             END;
- 3378                                             braceCls := savedCls; .)
- 3379                                          (. astCur := astNode; .) .
- 3380    BraceElem<vt: SymTab.TypeIndex; VAR sq: QbeGen.QVal;
- 3381              VAR node, tail: AST.Node>
- 3382                                          (. VAR et, et2: SymTab.TypeIndex;
- 3383                                               qe, q2: QbeGen.QVal;
- 3384                                               v, v2, reps, k: INTEGER;
- 3385                                               elem: SymTab.TypeIndex;
- 3386                                               lo: INTEGER;
- 3387                                               span: CARDINAL;
- 3388                                               cl, cl2: INTEGER;
- 3389                                               hasR, hasB: BOOLEAN;
- 3390                                               astEl: AST.Node; .)
- 3391      =                                   (. hasR := FALSE; hasB := FALSE;
- 3392                                             reps := 1; .)
- 3393        Expr<et, qe> (. astEl := astCur; .)
- 3394        [ ".." Expr<et2, q2>              (. astEl := AST.MakeBin(
- 3395                                               AST.NkSubrange, 0, astEl, astCur);
- 3396                                             hasR := TRUE; .) ]
- 3397        [ "BY" Expr<et2, q2>              (. hasB := TRUE; .) ]
- 3398                                          (. IF braceCls = SymTab.ClSet THEN
- 3399                                               IF hasB THEN SemError(230) END;
- 3400                                               lo := SymTab.SetBaseLo(vt);
- 3401                                               span := SymTab.SetCount(vt);
- 3402                                               IF (et = SymTab.InvalidType)
- 3403                                                  OR (hasR AND (et2 =
- 3404                                                     SymTab.InvalidType)) THEN
- 3405                                               ELSE cl :=
- 3406                                                      SymTab.ClassOf(et);
- 3407                                                 IF hasR THEN
- 3408                                                   cl2 :=
- 3409                                                     SymTab.ClassOf(et2)
- 3410                                                 ELSE cl2 := SymTab.ClInt
- 3411                                                 END;
- 3412                                                 IF NOT SymTab.SetElemClassOk(cl)
- 3413                                                    OR (hasR AND NOT
- 3414                                                       SymTab.SetElemClassOk(cl2))
- 3415                                                 THEN
- 3416                                                   SemError(222)
- 3417                                                 ELSIF hasR
- 3418   AND SymTab.ConstInt(qe, v)
- 3419   AND SymTab.ConstInt(q2,
- 3420                                                       v2)
- 3421   AND ((v < lo)
- 3422                                                       OR (v2 < lo)
- 3423                                                       OR (v >= lo +
- 3424                                                          VAL(INTEGER, span))
- 3425                                                       OR (v2 >= lo +
- 3426                                                          VAL(INTEGER, span))
- 3427                                                       OR (v > v2)) THEN
- 3428                                                   SemError(222)
- 3429                                                  ELSIF hasR THEN
- 3430                                                    QbeGen.SetRange(sq, qe, q2,
- 3431                                                      lo, span)
- 3432                                                  ELSIF SymTab.ConstInt(qe,
- 3433                                                          v)
- 3434   AND ((v < lo)
- 3435                                                        OR (v >= lo +
- 3436                                                           VAL(INTEGER,
- 3437                                                             span))) THEN
- 3438                                                    SemError(222)
- 3439                                                  ELSE QbeGen.SetBit(sq, qe,
- 3440                                                    lo, span)
- 3441                                                 END
- 3442                                               END
- 3443                                             ELSIF (braceCls = SymTab.ClArray)
- 3444                                                OR (braceCls =
- 3445                                                   SymTab.ClRecord)
- 3446                                                OR (braceCls =
- 3447                                                   SymTab.ClClass) THEN
- 3448                                               IF hasR THEN SemError(230) END;
- 3449                                               reps := 1;
- 3450                                               IF hasB THEN
- 3451                                                 IF SymTab.ConstInt(q2, v2)
- 3452   AND (v2 >= 1) THEN
- 3453                                                   reps := v2
- 3454                                                 ELSE SemError(230)
- 3455                                                 END
- 3456                                               END;
- 3457                                               k := 0;
- 3458                                               WHILE k < reps DO
- 3459                                                 QbeGen.CtorElem(qe);
- 3460                                                 INC(k)
- 3461                                               END
- 3462                                             END; .)
- 3463                                          (. (* the BY form repeats the
- 3464                                               element; keep the AST in
- 3465                                               step with CtorElem *)
- 3466                                             k := 0;
- 3467                                             WHILE k < reps DO
- 3468                                               AstAppend(AST.NkBlock,
- 3469                                                 node, tail, astEl);
- 3470                                               INC(k)
- 3471                                             END; .) .
- 3472    SetElem<st: SymTab.TypeIndex; sq: QbeGen.QVal; node: AST.Node>         (. VAR et, et2: SymTab.TypeIndex;
- 3473                                               qe, q2: QbeGen.QVal;
- 3474                                               v, v2: INTEGER;
- 3475                                               lo: INTEGER;
- 3476                                               span: CARDINAL;
- 3477                                               cl, cl2: INTEGER;
- 3478                                               hasR: BOOLEAN;
- 3479                                               astEl: AST.Node; .)
- 3480      =                                   (. hasR := FALSE; .)
- 3481        Expr<et, qe> (. astEl := astCur; .)
- 3482        [ ".." Expr<et2, q2>              (. astEl := AST.MakeBin(
- 3483                                               AST.NkSubrange, 0, astEl, astCur);
- 3484                                             hasR := TRUE; .) ]
- 3485                                          (. lo := SymTab.SetBaseLo(st);
- 3486                                             span := SymTab.SetCount(st);
- 3487                                             IF (et = SymTab.InvalidType)
- 3488                                                OR (hasR AND (et2 =
- 3489                                                   SymTab.InvalidType)) THEN
- 3490                                             ELSE cl :=
- 3491                                                    SymTab.ClassOf(et);
- 3492                                               IF hasR THEN
- 3493                                                 cl2 :=
- 3494                                                   SymTab.ClassOf(et2)
- 3495                                               ELSE cl2 := SymTab.ClInt
- 3496                                               END;
- 3497                                               IF NOT SymTab.SetElemClassOk(cl)
- 3498                                                  OR (hasR AND NOT
- 3499                                                     SymTab.SetElemClassOk(cl2))
- 3500                                               THEN
- 3501                                                 SemError(222)
- 3502                                               ELSIF hasR
- 3503   AND SymTab.ConstInt(qe, v)
- 3504   AND SymTab.ConstInt(q2,
- 3505                                                     v2)
- 3506   AND ((v < lo)
- 3507                                                     OR (v2 < lo)
- 3508                                                     OR (v >= lo +
- 3509                                                        VAL(INTEGER, span))
- 3510                                                     OR (v2 >= lo +
- 3511                                                        VAL(INTEGER, span))
- 3512                                                     OR (v > v2)) THEN
- 3513                                                 SemError(222)
- 3514                                                ELSIF hasR THEN
- 3515                                                  QbeGen.SetRange(sq, qe, q2,
- 3516                                                    lo, span)
- 3517                                                ELSIF SymTab.ConstInt(qe,
- 3518                                                        v)
- 3519   AND ((v < lo)
- 3520                                                      OR (v >= lo +
- 3521                                                         VAL(INTEGER,
- 3522                                                           span))) THEN
- 3523                                                  SemError(222)
- 3524                                                ELSE QbeGen.SetBit(sq, qe,
- 3525                                                  lo, span)
- 3526                                               END
- 3527                                             END; .)
- 3528                                          (. AST.SetChild(node,
- 3529                                               AST.NChild(node), astEl); .) .
- 3530    GetIdent<VAR n: SymTab.Name>
- 3531      = ident                             (. LexName(n); .) .
- 3532  
- 3533  END M2.
+ 3290                                                 ELSIF (c1 = SymTab.ClInt)
+ 3291    AND (c2 = SymTab.ClReal) THEN
+ 3292                                                   QbeGen.ConvIR(q, qa);
+ 3293                                                   QbeGen.CopyOp(qa, q);
+ 3294                                                   t := vt
+ 3295                                                 ELSIF (c1 = SymTab.ClLong)
+ 3296    AND (c2 = SymTab.ClReal) THEN
+ 3297                                                   QbeGen.ConvLR(q, qa);
+ 3298                                                   QbeGen.CopyOp(qa, q);
+ 3299                                                   t := vt
+ 3300                                                 ELSIF (c1 = SymTab.ClReal)
+ 3301    AND (c2 = SymTab.ClInt) THEN
+ 3302                                                   QbeGen.ConvRI(q, qa);
+ 3303                                                   QbeGen.CopyOp(qa, q);
+ 3304                                                   t := vt
+ 3305                                                 ELSIF (c1 = SymTab.ClReal)
+ 3306    AND (c2 = SymTab.ClLong) THEN
+ 3307                                                   QbeGen.ConvRL(q, qa);
+ 3308                                                   QbeGen.CopyOp(qa, q);
+ 3309                                                   t := vt
+ 3310                                                 ELSIF ((c1 = SymTab.ClInt)
+ 3311                                                     OR (c1 =
+ 3312                                                        SymTab.ClChar)
+ 3313                                                     OR (c1 =
+ 3314                                                        SymTab.ClBool)
+ 3315                                                     OR (c1 =
+ 3316                                                        SymTab.ClEnum))
+ 3317   AND ((c2 = SymTab.ClInt)
+ 3318                                                     OR (c2 =
+ 3319                                                        SymTab.ClChar)
+ 3320                                                     OR (c2 =
+ 3321                                                        SymTab.ClBool)
+ 3322                                                     OR (c2 =
+ 3323                                                        SymTab.ClEnum)) THEN
+ 3324                                                   t := vt
+ 3325                                                 ELSIF (c1 = SymTab.ClPtr)
+ 3326   AND (c2 = SymTab.ClPtr) THEN
+ 3327                                                   t := vt
+ 3328                                                 ELSIF (c1 = SymTab.ClReal)
+ 3329   AND (c2 = SymTab.ClReal) THEN
+ 3330                                                   t := vt
+ 3331                                                 ELSE SemError(230);
+ 3332                                                   t := SymTab.InvalidType
+ 3333                                                 END
+ 3334                                               END
+ 3335                                             END; .)
+ 3336      | "(" Expr<et, q> ")"               (. t := et; astIsLit := TRUE; .)
+ 3337      | SetLit<st, sq>                    (. astIsLit := TRUE; t := st;
+ 3338                                             QbeGen.CopyOp(sq, q); .)
+ 3339      | ( "NOT" | "~" ) Fact<t2, q2>      (. astNot := astCur;
+ 3340                                             IF SymTab.BoolCheck(t2) THEN
+ 3341                                               t := SymTab.BoolType()
+ 3342                                             ELSE SemError(212);
+ 3343                                               t := SymTab.InvalidType END;
+ 3344                                             IF t # SymTab.InvalidType THEN
+ 3345                                                QbeGen.CopyOp("@", q)
+ 3346                                             ELSE QbeGen.CopyOp("0", q)
+ 3347                                             END;
+ 3348                                             astIsLit := TRUE;
+ 3349                                             astCur := AST.MakeUn(
+ 3350                                               AST.NkUnary, AST.OpNot, astNot); .)
+ 3351      )
+ 3352      (. IF NOT astIsLit THEN astCur := AST.NoNode END; .)
+ 3353             (. IF astCur # AST.NoNode THEN AST.SetTy(astCur, t) END; .) .
+ 3354    (* Set literals are SET OF [0..255] (8 words); elements validated
+ 3355       0..255 statically when foldable (222 otherwise), runtime trap
+ 3356       for computed elements. Ranges always lower via SetRange. *)
+ 3357    SetLit<VAR t: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 3358                                          (. VAR astNode: AST.Node; .)
+ 3359      = "{"                               (. t := SymTab.NewSet(
+ 3360                                               SymTab.NewSubR(0, 255));
+ 3361                                             astNode := AST.MakeNode(AST.NkSetLit);
+ 3362                                             QbeGen.NewSetTemp(8, q);
+ 3363                                             QbeGen.SetZero(q, 8); .)
+ 3364        [ SetElem<t, q, astNode> { "," SetElem<t, q, astNode> } ]
+ 3365        "}"                               (. astCur := astNode; .) .
+ 3366    (* Typed brace constructor: TypeName{ elems } — BITSET{0} (a set)
+ 3367       or ArrayName{...} (an array constructor, GNU Modula-2).  The
+ 3368       declared type sets the width (set) or element type (array). *)
+ 3369    TypedBraceLit<vt: SymTab.TypeIndex; VAR q: QbeGen.QVal>
+ 3370                                          (. VAR nw: CARDINAL;
+ 3371                                               astNode, astTail: AST.Node;
+ 3372                                               savedCls: INTEGER; .)
+ 3373      = "{"                               (. savedCls := braceCls;
+ 3374                                             astNode := AST.MakeNode(AST.NkBraceLit);
+ 3375                                             AST.SetTy(astNode, vt);
+ 3376                                             astTail := astNode;
+ 3377                                             IF vt = SymTab.InvalidType THEN
+ 3378                                               braceCls := -1
+ 3379                                             ELSE braceCls :=
+ 3380                                                    SymTab.ClassOf(vt)
+ 3381                                             END;
+ 3382                                             IF braceCls = SymTab.ClSet THEN
+ 3383                                               IF vt = SymTab.InvalidType THEN
+ 3384                                                 nw := 8
+ 3385                                               ELSE nw := SymTab.SetWords(vt);
+ 3386                                                 IF nw = 0 THEN nw := 8 END
+ 3387                                               END;
+ 3388                                               QbeGen.NewSetTemp(nw, q);
+ 3389                                               QbeGen.SetZero(q, nw)
+ 3390                                             ELSIF (braceCls =
+ 3391                                                    SymTab.ClArray)
+ 3392                                                OR (braceCls =
+ 3393                                                    SymTab.ClRecord)
+ 3394                                                OR (braceCls =
+ 3395                                                    SymTab.ClClass) THEN
+ 3396                                               QbeGen.CtorBegin(vt)
+ 3397                                             ELSE
+ 3398                                               IF vt # SymTab.InvalidType THEN
+ 3399                                                 SemError(230) END;
+ 3400                                               braceCls := -1
+ 3401                                             END; .)
+ 3402        [ BraceElem<vt, q, astNode, astTail>
+ 3403          { "," BraceElem<vt, q, astNode, astTail> } ]
+ 3404        "}"                               (. IF (braceCls = SymTab.ClArray)
+ 3405                                                OR (braceCls =
+ 3406                                                   SymTab.ClRecord)
+ 3407                                                OR (braceCls =
+ 3408                                                   SymTab.ClClass) THEN
+ 3409                                               QbeGen.CtorEnd(q)
+ 3410                                             ELSIF braceCls # SymTab.ClSet THEN
+ 3411                                               QbeGen.CopyOp("0", q)
+ 3412                                             END;
+ 3413                                             braceCls := savedCls; .)
+ 3414                                          (. astCur := astNode; .) .
+ 3415    BraceElem<vt: SymTab.TypeIndex; VAR sq: QbeGen.QVal;
+ 3416              VAR node, tail: AST.Node>
+ 3417                                          (. VAR et, et2: SymTab.TypeIndex;
+ 3418                                               qe, q2: QbeGen.QVal;
+ 3419                                               v, v2, reps, k: INTEGER;
+ 3420                                               elem: SymTab.TypeIndex;
+ 3421                                               lo: INTEGER;
+ 3422                                               span: CARDINAL;
+ 3423                                               cl, cl2: INTEGER;
+ 3424                                               hasR, hasB: BOOLEAN;
+ 3425                                               astEl: AST.Node; .)
+ 3426      =                                   (. hasR := FALSE; hasB := FALSE;
+ 3427                                             reps := 1; .)
+ 3428        Expr<et, qe> (. astEl := astCur; .)
+ 3429        [ ".." Expr<et2, q2>              (. astEl := AST.MakeBin(
+ 3430                                               AST.NkSubrange, 0, astEl, astCur);
+ 3431                                             hasR := TRUE; .) ]
+ 3432        [ "BY" Expr<et2, q2>              (. hasB := TRUE; .) ]
+ 3433                                          (. IF braceCls = SymTab.ClSet THEN
+ 3434                                               IF hasB THEN SemError(230) END;
+ 3435                                               lo := SymTab.SetBaseLo(vt);
+ 3436                                               span := SymTab.SetCount(vt);
+ 3437                                               IF (et = SymTab.InvalidType)
+ 3438                                                  OR (hasR AND (et2 =
+ 3439                                                     SymTab.InvalidType)) THEN
+ 3440                                               ELSE cl :=
+ 3441                                                      SymTab.ClassOf(et);
+ 3442                                                 IF hasR THEN
+ 3443                                                   cl2 :=
+ 3444                                                     SymTab.ClassOf(et2)
+ 3445                                                 ELSE cl2 := SymTab.ClInt
+ 3446                                                 END;
+ 3447                                                 IF NOT SymTab.SetElemClassOk(cl)
+ 3448                                                    OR (hasR AND NOT
+ 3449                                                       SymTab.SetElemClassOk(cl2))
+ 3450                                                 THEN
+ 3451                                                   SemError(222)
+ 3452                                                 ELSIF hasR
+ 3453   AND SymTab.ConstInt(qe, v)
+ 3454   AND SymTab.ConstInt(q2,
+ 3455                                                       v2)
+ 3456   AND ((v < lo)
+ 3457                                                       OR (v2 < lo)
+ 3458                                                       OR (v >= lo +
+ 3459                                                          VAL(INTEGER, span))
+ 3460                                                       OR (v2 >= lo +
+ 3461                                                          VAL(INTEGER, span))
+ 3462                                                       OR (v > v2)) THEN
+ 3463                                                   SemError(222)
+ 3464                                                  ELSIF hasR THEN
+ 3465                                                    QbeGen.SetRange(sq, qe, q2,
+ 3466                                                      lo, span)
+ 3467                                                  ELSIF SymTab.ConstInt(qe,
+ 3468                                                          v)
+ 3469   AND ((v < lo)
+ 3470                                                        OR (v >= lo +
+ 3471                                                           VAL(INTEGER,
+ 3472                                                             span))) THEN
+ 3473                                                    SemError(222)
+ 3474                                                  ELSE QbeGen.SetBit(sq, qe,
+ 3475                                                    lo, span)
+ 3476                                                 END
+ 3477                                               END
+ 3478                                             ELSIF (braceCls = SymTab.ClArray)
+ 3479                                                OR (braceCls =
+ 3480                                                   SymTab.ClRecord)
+ 3481                                                OR (braceCls =
+ 3482                                                   SymTab.ClClass) THEN
+ 3483                                               IF hasR THEN SemError(230) END;
+ 3484                                               reps := 1;
+ 3485                                               IF hasB THEN
+ 3486                                                 IF SymTab.ConstInt(q2, v2)
+ 3487   AND (v2 >= 1) THEN
+ 3488                                                   reps := v2
+ 3489                                                 ELSE SemError(230)
+ 3490                                                 END
+ 3491                                               END;
+ 3492                                               k := 0;
+ 3493                                               WHILE k < reps DO
+ 3494                                                 QbeGen.CtorElem(qe);
+ 3495                                                 INC(k)
+ 3496                                               END
+ 3497                                             END; .)
+ 3498                                          (. (* the BY form repeats the
+ 3499                                               element; keep the AST in
+ 3500                                               step with CtorElem *)
+ 3501                                             k := 0;
+ 3502                                             WHILE k < reps DO
+ 3503                                               AstAppend(AST.NkBlock,
+ 3504                                                 node, tail, astEl);
+ 3505                                               INC(k)
+ 3506                                             END; .) .
+ 3507    SetElem<st: SymTab.TypeIndex; sq: QbeGen.QVal; node: AST.Node>         (. VAR et, et2: SymTab.TypeIndex;
+ 3508                                               qe, q2: QbeGen.QVal;
+ 3509                                               v, v2: INTEGER;
+ 3510                                               lo: INTEGER;
+ 3511                                               span: CARDINAL;
+ 3512                                               cl, cl2: INTEGER;
+ 3513                                               hasR: BOOLEAN;
+ 3514                                               astEl: AST.Node; .)
+ 3515      =                                   (. hasR := FALSE; .)
+ 3516        Expr<et, qe> (. astEl := astCur; .)
+ 3517        [ ".." Expr<et2, q2>              (. astEl := AST.MakeBin(
+ 3518                                               AST.NkSubrange, 0, astEl, astCur);
+ 3519                                             hasR := TRUE; .) ]
+ 3520                                          (. lo := SymTab.SetBaseLo(st);
+ 3521                                             span := SymTab.SetCount(st);
+ 3522                                             IF (et = SymTab.InvalidType)
+ 3523                                                OR (hasR AND (et2 =
+ 3524                                                   SymTab.InvalidType)) THEN
+ 3525                                             ELSE cl :=
+ 3526                                                    SymTab.ClassOf(et);
+ 3527                                               IF hasR THEN
+ 3528                                                 cl2 :=
+ 3529                                                   SymTab.ClassOf(et2)
+ 3530                                               ELSE cl2 := SymTab.ClInt
+ 3531                                               END;
+ 3532                                               IF NOT SymTab.SetElemClassOk(cl)
+ 3533                                                  OR (hasR AND NOT
+ 3534                                                     SymTab.SetElemClassOk(cl2))
+ 3535                                               THEN
+ 3536                                                 SemError(222)
+ 3537                                               ELSIF hasR
+ 3538   AND SymTab.ConstInt(qe, v)
+ 3539   AND SymTab.ConstInt(q2,
+ 3540                                                     v2)
+ 3541   AND ((v < lo)
+ 3542                                                     OR (v2 < lo)
+ 3543                                                     OR (v >= lo +
+ 3544                                                        VAL(INTEGER, span))
+ 3545                                                     OR (v2 >= lo +
+ 3546                                                        VAL(INTEGER, span))
+ 3547                                                     OR (v > v2)) THEN
+ 3548                                                 SemError(222)
+ 3549                                                ELSIF hasR THEN
+ 3550                                                  QbeGen.SetRange(sq, qe, q2,
+ 3551                                                    lo, span)
+ 3552                                                ELSIF SymTab.ConstInt(qe,
+ 3553                                                        v)
+ 3554   AND ((v < lo)
+ 3555                                                      OR (v >= lo +
+ 3556                                                         VAL(INTEGER,
+ 3557                                                           span))) THEN
+ 3558                                                  SemError(222)
+ 3559                                                ELSE QbeGen.SetBit(sq, qe,
+ 3560                                                  lo, span)
+ 3561                                               END
+ 3562                                             END; .)
+ 3563                                          (. AST.SetChild(node,
+ 3564                                               AST.NChild(node), astEl); .) .
+ 3565    GetIdent<VAR n: SymTab.Name>
+ 3566      = ident                             (. LexName(n); .) .
+ 3567  
+ 3568  END M2.
 
     0 errors
 

+ 20 - 0
compiler/src/scanner.frm

@@ -213,6 +213,22 @@ PROCEDURE PopPos;
     errors := saveErrors[posDepth]
   END PopPos;
 
+PROCEDURE SeekTo (p: INT32);
+(* Reposition the scanner to the token starting at buffer offset p
+   (two-phase re-parse).  Replays NextCh from the start so curLine /
+   lineStart / lastCh match a fresh parse exactly; the buffer is
+   in-memory so this is O(p) with no file I/O.  Published pos / len /
+   line / col still describe the previous token afterwards — the caller
+   must Get immediately, exactly like the priming Get in Parse. *)
+  VAR k: INT32;
+  BEGIN
+    curLine := 1; lineStart := -2; bp := -1;
+    ch := EOF; lastCh := EOF;
+    oldEols := 0; apx := 0; bp0 := p;
+    k := 0;
+    WHILE k <= p DO NextCh; INC(k) END
+  END SeekTo;
+
 BEGIN
   -->initializations
   Error := Err; lastCh := EOF;
@@ -261,4 +277,8 @@ PROCEDURE PushPos;
 PROCEDURE PopPos;
 (* Restore the state saved by PushPos *)
 
+PROCEDURE SeekTo (p: INT32);
+(* Reposition the scanner to buffer offset p (two-phase re-parse);
+   caller must Get immediately afterwards *)
+
 END -->modulename.

+ 34 - 0
docs/plan-two-phase-parse.md

@@ -136,3 +136,37 @@ alone.
 - **Next**: milestone 2 — record body spans during the probe, add the
   body-entry production, and re-parse bodies after the declarations
   (driver-level restart), byte-compared against the default.
+- **2026-10-16, milestone 2a (spans + SeekTo, still inert).**
+  - `scanner.frm`: `SeekTo(p)` — replays `NextCh` from offset 0 over
+    the in-memory buffer (O(p), no file I/O), so `curLine`/`lineStart`/
+    `lastCh` match a fresh parse exactly. Published `pos`/`len` still
+    describe the previous token afterwards — caller must `Get`
+    immediately (same contract as the priming `Get` in `Parse`).
+  - `M2.atg`: span table (`nSpans`/`spanName`/`spanStart`, per-parse,
+    1024 entries) recorded in `ProbeBody`; a `SeekTo(start)`+`Adv`
+    round-trip check per body (`sym`/`nextPos` equality) whose side
+    effects the trailing `PopPos` discards — mismatch prints
+    `twophase seek mismatch`, silent otherwise.
+  - Verified: 142-file sweep, zero `probe`/`seek` mismatches, zero
+    `.ssa` diffs; suite **196/196** (gate now greps both mismatch
+    kinds); **fixpoint OK (3,584,690 bytes)**. Positive controls: temp
+    print showed the check firing per body with the flag on (reverted),
+    and a truncated file reports `probe mismatch`.
+  - **Finding (sharpened V3 rule).** The first 2a cut called
+    `NoteSpan` (defined *after* `ProbeBody`, not in `M2P.def`) and
+    stage 2 failed 233 + `END M2P` knock-ons. Bisected to the rule:
+    V3 has **no forward procedure tolerance at all** — even `P;` with
+    `P` declared two lines later is 233 (+201 at EOF). The existing
+    sources self-compile only because every `.mod` is paired with its
+    `.def`, which the driver parses first (so e.g. `SemError` is
+    already declared when `NoteLabel`'s body compiles), plus strict
+    declaration-before-use inside modules. Fix was ordering (declare
+    `NoteSpan` before its caller), same as the `CopyNm` precedent.
+    The `FwdVar` tolerance covers module-level *variables* only.
+- **Next**: milestone 2b — SymTab save/re-enter-body-scope primitive
+  (no re-push exists today; all resumes allocate fresh scopes —
+  mapping in subagent record `ses_ebc94df66ffeTZpjrrFnZS1GsF`) plus the
+  closer-split (phase-1 skip must replicate `CloseProc`/`EndFunc`/
+  `ScopeLeave` effects without a body); then 2c deferral wiring
+  (skip + placeholder + end-of-unit re-parse worklist, nested spans
+  append during phase 2), byte-compared; then 2d flip + delete.