Slisp compile Lisp en assemblée autonome sans GC, sans macros, sans citation

Steve Kemp's Slisp is a compiler that reads Lisp programs and spits out standalone assembly for Linux/amd64. No REPL, no interpreter, no garbage collector, no macros, no quote. Just a straight shot from s-expression to an ELF binary.

What Slisp Actually Does

Input a Lisp file and Slisp emits x86-64 assembly following the SysV ABI. You assemble with NASM, link with ld, and get a native executable. The compiler supports integers, strings, lambdas with closures, lists, and a small set of special forms: cond, defun, do, if, lambda, let, list, and set!. A standard library written in Slisp itself (in stdlib.slisp) gets prepended unless you pass -stdlib=false.

Take the factorial example: (defun fact (n) (if (<= n 1) 1 (* n (fact (- n 1))))). Compile it, link it, run it. That's it.

The Anti-Features Are the Point

No garbage collection. Heap-allocated cons cells live in a rough bump-allocator. No macros, which Kemp explicitly calls out as "a lot of work" without quasiquote. No quote, because that would need eval, and a compiler can't eval at compile time easily. These aren't bugs; they're deliberate constraints that keep the implementation small and fast.

Kemp built Slisp after getting bogged down in a previous homegrown language (s-lang) where typing and syntax complexity forced a rewrite. Lisp's trivial parse tree and the well-known SysV ABI let him focus on the compiler core.

Compilation Pipeline and Testing

Build the compiler with go build ., then pipe the output through NASM and ld. A Makefile automates it. The test/ directory contains functional tests that compile programs (factorial, fibonacci, fizzbuzz, even a brainfuck interpreter) and compare output to known-good results. There are also Go unit tests for the lexer, parser, compiler, and environment packages, plus fuzz testing via go test -fuzz=FuzzProject.

Slisp isn't a toy; it passes a real test suite and handles recursion, closures, and type detection (int?, cons?). It's a compiler you can actually trace through from source to machine code.

For engineers who want to understand how a compiler can map Lisp to assembly without the overhead of a runtime or GC, Slisp is a clean, working implementation. No bloat, no hand-waving.

Source: Slisp: Simple Lisp compiler (Linux/amd64)
Domain: github.com