a7fe165684
"pure" universally means side-effect-free (GCC __attribute__((pure)), FP purity, D's pure) — the opposite of a register-clobbering context switch. The concept is "naked": no compiler-generated prologue/epilogue, body is raw asm that emits its own ret. That is the established term everywhere (LLVM's naked function attribute — which we literally emit — plus Zig callconv(.naked), Rust #[naked], GCC/Clang __attribute__ ((naked))). Rename the keyword + everything keyed off it so concept, surface, field, and the emitted LLVM attribute all agree. - ast.zig: ABI enum variant pure -> naked (+ doc). - parser: accept abi(.naked); error text updated. - IR Function.is_pure -> is_naked; type_resolver/decl/generic/pack/ emit_llvm references updated; diagnostics say abi(.naked). - examples 1800-1803 renamed *-pure-* -> *-naked-* (source + expected/ snapshots; .ir/.exit/.stdout/.stderr are byte-identical — the emitted IR is unchanged, only the keyword spelling differs). - docs (PLAN-FIBERS, CHECKPOINT-FIBERS, PLAN-POST-METATYPE, the design roadmap, the compiler-API checkpoint/design) updated; the naming rationale now records why .naked over .pure. No semantic change — pure cosmetics. Suite green (725/0).
26 lines
1.1 KiB
Plaintext
26 lines
1.1 KiB
Plaintext
// Stream B1 (fibers) — an `abi(.pure)` function with PARAMETERS reads its args
|
|
// from ABI registers (the shape the fiber context-switch needs: `swap_context`
|
|
// reads `from`/`to` from x0/x1).
|
|
//
|
|
// A naked function has no frame, so params are NOT spilled to stack slots — they
|
|
// stay in their ABI registers and the asm body reads them directly. Here `a` is
|
|
// in x0, `b` in x1 (aarch64 AAPCS), and the result returns in x0: `add x0, x0,
|
|
// x1`. The lowering skips the param-alloca loop for `.pure` (decl.zig /
|
|
// generic.zig); the LLVM args are declared-but-unused, which the verifier allows
|
|
// (spilling them would emit `store i64 %0, …` → "cannot use argument of naked
|
|
// function"). aarch64-pinned; runs end-to-end (exit 42), ir-only on a mismatch.
|
|
//
|
|
// Regression for an adversarial-review finding: before the param-alloca guard, a
|
|
// param-bearing `.pure` fn emitted invalid LLVM (loud verifier error) instead of
|
|
// a working naked function.
|
|
add :: (a: i64, b: i64) -> i64 abi(.pure) {
|
|
asm volatile {
|
|
#string A
|
|
add x0, x0, x1
|
|
ret
|
|
A
|
|
};
|
|
}
|
|
|
|
main :: () -> i64 { return add(40, 2); }
|