luacretro

The shared Lua compiler front-end for the gtlua (GameTank / 6502), gbalua (Game Boy Advance / ARM), mdlua (Sega Genesis / 68000), neslua (NES / 6502), and c64lua (Commodore 64 / 6510) console SDKs. A PICO-8-flavored, statically-typed Lua subset that is ahead-of-time compiled to C (then to a native ROM by each SDK) - there is no Lua interpreter or VM on the console, just native machine code. The static subset (no heap, no closures, fixed-point numbers) is what makes that whole-program AOT compilation possible.

Each SDK depends on luacretro and calls compile(source, file, opts) with its platform target and its builtin tables:

import { compile } from "luacretro";
const { ok, c, diagnostics, callGraph, stubs } =
  compile(src, "main.lua", { target: "gametank", sdkName: "gtlua",
                             builtins, members, callbacks });

Targets and capabilities

The emitter derives every per-platform behavior from a single capability table (CAPS in compiler/emit.js) keyed by opts.target:

| target | zpFastcall | banked | nativeDiv | colorBake | framebuffer | cName | |------------|:----------:|:------:|:---------:|:---------:|:-----------:|-------| | gametank | ✓ | ✓ | | ✓ | ✓ | gt_ | | gba | | | ✓ | | ✓ | gba_| | md | | | ✓ | | ✓ | md_ | | nes | ✓ | | | ✓ | | nes_| | c64 | ✓ | | | ✓ | ✓ | c64_|

• zpFastcall — the 6502 zero-page fastcall ABI (draw builtins stage args in gt_a*, user fns in gt_p*, fixed mul/div through fa/fb).
• banked — GameTank FLASH2M cross-bank far-call machinery.
• nativeDiv — hardware integer divide/modulo (else the runtime helpers).
• colorBake — bake a static P8 color literal 0-15 to a raw platform palette byte at compile time (needs opts.p8Palette).
• framebuffer — a full pixel surface (every draw verb lands); nes is a tile/sprite machine, so its SDK enables only the verbs it can honor.

Per-target static-allocation caps come from opts.limits ({arrayMax, poolMax}); the defaults preserve the historical gtlua numbers.

The compiler is browser-safe (no node: / Buffer) so the web IDEs bundle it unchanged. See SPEC.md for the language. The Python-family sibling is pycretro.