TurboModula2/docs/compiler/00-overview.md

Turbo Modula-2 — Compiler outline

Target: give meaning back to procN / globalN in the Reversing-Turbo-Modula2-main/decompiled/COMPILER/ sources, which compile but are unreadable.

Status: outline only, no semantic change to upstream sources. Upstream folders are git-ignored (see ../.gitignore); only docs/compiler/ is versioned.

Layout

docs/compiler/
  00-overview.md        this file, map + reading order
  10-folders.md         what each upstream folder contains
  20-compiler-module.md Compiler.MOD/DEF: Record descriptor + Init procs
  30-scanner-module.md  Scanner: buffer, GetSym, Accept/Expect/Test
  40-symtab-errors.md   SymTab scopes + Errors reporting/recovery
  50-codegen.md         CodeGen MCode emitter + 2KB window + fixups
  60-frontend.md        COMPILE link: Pass1 + Statement + Express (no .MOD yet)
  70-rename-plan.md     ordered rename work plan procN/globalN -> real names
  TAGGED-SUMMARY.md     one-page tagged snapshot for `git tag`

Compiler shape (recall)

Resident, overlaid in M2.COM:

• Compiler + Scanner + SymTab + Errors + CodeGen

Dynamically loaded via Loader.Call:

• COMPILE = link of Pass1 + Statemen + Express
• GENZ80 = native-code backend (if requested)

Drivers:

• C.MOD (MODULE M2C): ReadString -> inName -> Scanner.Compile
• Scanner.Compile (proc30): MARK, Compiler.proc2, Call("COMPILE"), then Call("GENZ80") if Compiler.global25
• ComLine: commandLine, inName, outName, codepos, execute

Reading order (suggested)

1. 20-compiler-module.md — the Record descriptor unlocks everything.
2. 30-scanner-module.md — token codes, GetSym/Accept/Expect.
3. 50-codegen.md — opcode table + Emit/Peek/Poke/Fixup.
4. 40-symtab-errors.md — scopes, .SYM import/export, error recovery.
5. 60-frontend.md — parsers that consume 1-4.
6. 70-rename-plan.md — execute renames in that dependency order.

Note on sources: decompiled/COMPILER/*.{DEF,MOD} are CP/M text (CRLF + 0x1A). Plain readers fail; use:

tr -d '\032\r' < Reversing-Turbo-Modula2-main/decompiled/COMPILER/SCANNER.MOD | less

Turbo-Modula-2-Reloaded-main/disk_content/COMPILER.DIR/SCANNER.MOD is a stub (30x PROCnn; BEGIN END); the real logic is in the Reversing-.../MCode_disassembly/*.txt disassemblies.