TP3/shell/tests/fixtures/t80_realconst.pas

program t80_realconst;

{ t80 -- a REAL record field assigned from integer constants.

  CALC.INC:163 is `Value := 0'; Value is a 6-byte Real.  TP3's layout is
  measured in CALC-PORT.md against the cells holding 1, 2, 3, 4, 5:

      value = (1 + N/2^39) * 2^(E-129)

  byte 0 = E biased by 129, bytes 1..5 = N little-endian, sign in bit 7 of
  byte 5, all-zero = 0.0.

  Only compile-time ordinal constants and 6-byte copies are accepted; real
  arithmetic/formatting is a later stage and is refused loudly.  The .out
  checks the fields A and B on either side of V (the store is six bytes, not
  more), and tests/check_realconst.py asserts the six bytes themselves
  against the measured table. }

type
   Cell = record
      V : real;
      A, B : integer;
   end;

var
   g : array [1..2, 1..3] of Cell;
   i, j : integer;

begin
   with g[2,3] do
   begin
      V := 0;
      A := 11;
      B := 12
   end;
   with g[2,3] do
      V := 1;
   i := 2;
   j := 3;
   with g[i,j] do
      V := 1;          (* the DI form: C6 45 <off> <byte> *)
   with g[2,3] do
      V := 2;
   with g[2,3] do
      V := 3;
   with g[2,3] do
      V := 5;
   with g[1,1] do
      V := 3;
   with g[i,j] do
      V := g[1,1].V;   (* 6-byte copy, destination through DI *)
   with g[2,3] do
      A := A + B;
   writeln (g[2,3].A);
   writeln (g[1,1].A)
end.