/* * 907_f32arg_run — runtime + byte-id regression net for #143: passing an * f32 as a function argument must spill through the stack at the f32 class * width (MOVSS, 4-byte), not MOVSD (8-byte). cstage lowered the arg-push * (cgen.c N_CALL push) and arg-pop (the pop-into-XMM loop) with a hardcoded * MOVSD; wwstage already split f32/f64 via exprfloatkind (MOVSS for f32). * The result was a cs!=ww byte-id break on EVERY f32 argument — a pure * divergence, not a runtime miscompile (the callee reads its f32 param as * the low 32 bits via MOVSS regardless of how the caller spilled it), but * it blocked the cs==ww gate and therefore fold-5b (strconv f32tos, whose * core calls math.f32bits(n) — an f32 arg). * * ABI-correct form is MOVSS for single precision per SysV: ref/qbe * amd64/emit.c:524 — the slot->slot copy-through-XMM path (exactly ww's * X0 -> 8B stack slot -> XMMn arg-spill shape) narrows the class to Ks for * non-wide floats and emits movss (clstoa[Ks] == "ss"); movsd is the * double (Kd) form. The fix aligns cstage UP to MOVSS via the existing * op_for(node_isf32) helper at both the push and pop sites. wwstage is * unchanged. This is the f32-arg-push half of the float-register family * (#119 f32-arr-load, #122 f32-arr-store, #125 float-arr-index, #157 * tagged-float-return) — "f32 must route through the right XMM width." * * Each row carries BOTH dimensions (like 955 / 964 / 965): * (a) cstage `ww build` + run, asserting the exit code (end-to-end ABI: * the callee must read the correct f32 value out of the XMM reg). * (b) w6c vs w6c_ww `.s` cmp — FAILS if the stages diverge (rule-10). * * The 990-997 byte-id gates are BLIND to a reintroduction here only if the * gated selfhost tools never pass an f32 arg (they don't — bootstrap- * NEUTRAL), so this executed-and-byte-id-checked probe is the live net. */ #include #include #include #include #include #include static int runwait(const char *cmd) { int rc = system(cmd); if (rc == -1) return -1; if (WIFEXITED(rc)) return WEXITSTATUS(rc); return -1; } struct row { const char *label; const char *src; int want_exit; }; static const struct row rows[] = { /* single f32 var arg — the minimal repro. takef32(2.5) -> 2.5, * truncated to i32 == 2. On the bug the byte-id breaks (MOVSD push) * but the value still rounds (MOVSD carries the low 4 bytes too). */ { "single_var", "package main;\n" "fn takef32(x: f32) f32 = { return x; };\n" "export fn main() i32 = {\n" " let a: f32 = 2.5f32;\n" " let r: f32 = takef32(a);\n" " return r: i32;\n" "};\n", 2 }, /* f32 LITERAL directly as the arg (ken's original getj(1.0f32) * shape that surfaced #143). id(3.0f32) -> 3.0 -> 3. */ { "literal_arg", "package main;\n" "fn id(x: f32) f32 = { return x; };\n" "export fn main() i32 = {\n" " let r: f32 = id(3.0f32);\n" " return r: i32;\n" "};\n", 3 }, /* multiple f32 args — each pushed/popped independently; all must * use MOVSS on both stages. 1.5 + 2.5 + 4.0 == 8.0 (exact in f32). */ { "multi_f32", "package main;\n" "fn add3(a: f32, b: f32, c: f32) f32 = { return a + b + c; };\n" "export fn main() i32 = {\n" " let x: f32 = 1.5f32;\n" " let y: f32 = 2.5f32;\n" " let z: f32 = 4.0f32;\n" " let r: f32 = add3(x, y, z);\n" " return r: i32;\n" "};\n", 8 }, /* f32 + f64 MIX — the f64 arg must stay MOVSD (8-byte), the f32 args * MOVSS (4-byte), and BOTH stages must agree per-arg. 1.5 + 10.0 + * 0.5 == 12.0 (exact). Guards against the fix over-reaching to f64. */ { "mixed_f32_f64", "package main;\n" "fn mix(a: f32, b: f64, c: f32) f64 = " "{ return a: f64 + b + c: f64; };\n" "export fn main() i32 = {\n" " let p: f32 = 1.5f32;\n" " let q: f64 = 10.0;\n" " let s: f32 = 0.5f32;\n" " let r: f64 = mix(p, q, s);\n" " return r: i32;\n" "};\n", 12 }, /* STACK-passed f32: 10 float args — 8 ride X0..X7, args 9+10 stay on * the stack (fpidx >= 8). The push-spill still diverged on the bug; * this exercises the fpidx>=8 leave-on-stack arm. 1.0 * 10 == 10.0. */ { "stack_passed", "package main;\n" "fn ten(a: f32, b: f32, c: f32, d: f32, e: f32, f: f32, " "g: f32, h: f32, i: f32, j: f32) f32 = {\n" " return a + b + c + d + e + f + g + h + i + j;\n" "};\n" "export fn main() i32 = {\n" " let v: f32 = 1.0f32;\n" " let r: f32 = ten(v, v, v, v, v, v, v, v, v, v);\n" " return r: i32;\n" "};\n", 10 }, { NULL, NULL, 0 } }; static int slurp_eq(const char *a, const char *b) { FILE *fa = fopen(a, "rb"); FILE *fb = fopen(b, "rb"); if (!fa || !fb) { if (fa) fclose(fa); if (fb) fclose(fb); return -1; } int rc = 0; for (;;) { int ca = fgetc(fa); int cb = fgetc(fb); if (ca != cb) { rc = -1; break; } if (ca == EOF) break; } fclose(fa); fclose(fb); return rc; } int main(void) { const char *bin = getenv("BIN"); if (!bin) bin = "out/bin"; char absbin[1024]; if (bin[0] != '/') { char cwd[1024]; if (getcwd(cwd, sizeof cwd) == NULL) return 1; snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin); bin = absbin; } char w6c[1100], w6c_ww[1100]; snprintf(w6c, sizeof w6c, "%s/w6c", bin); snprintf(w6c_ww, sizeof w6c_ww, "%s/w6c_ww", bin); if (access(w6c_ww, X_OK) != 0) { fprintf(stderr, "f32arg: w6c_ww missing — cannot run the " "cs==ww byte-id gate (the whole point of this test)\n"); return 1; } int n = 0, fail = 0; for (int i = 0; rows[i].src; i++, n++) { char src[64]; snprintf(src, sizeof src, "/tmp/wwf32a_%d_%d.ww", getpid(), i); FILE *f = fopen(src, "wb"); if (f == NULL) { fail++; continue; } fputs(rows[i].src, f); fclose(f); /* (a) cstage build + run. */ char tmpdir[64]; snprintf(tmpdir, sizeof tmpdir, "/tmp/wwf32a_%d_d_%d", getpid(), i); mkdir(tmpdir, 0755); char cmd[2048]; snprintf(cmd, sizeof cmd, "cd %s && %s/ww build %s", tmpdir, bin, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: cstage build failed\n", rows[i].label); fail++; unlink(src); rmdir(tmpdir); continue; } char outbin[128]; const char *base = strrchr(src, '/'); base = base ? base + 1 : src; snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base); char *dot = strrchr(outbin, '.'); if (dot && strcmp(dot, ".ww") == 0) *dot = '\0'; int got = runwait(outbin); if (got != rows[i].want_exit) { fprintf(stderr, "row[%s]: cstage exit %d, want %d\n", rows[i].label, got, rows[i].want_exit); fail++; } unlink(outbin); rmdir(tmpdir); /* (b) cs==ww byte-id gate: emit .s from both stages, cmp. */ char cs_s[64], ws_s[64]; snprintf(cs_s, sizeof cs_s, "/tmp/wwf32a_%d_%d_cs.s", getpid(), i); snprintf(ws_s, sizeof ws_s, "/tmp/wwf32a_%d_%d_ww.s", getpid(), i); snprintf(cmd, sizeof cmd, "%s -o %s %s 2>/dev/null", w6c, cs_s, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: w6c failed\n", rows[i].label); fail++; unlink(src); continue; } snprintf(cmd, sizeof cmd, "%s -o %s %s 2>/dev/null", w6c_ww, ws_s, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: w6c_ww failed\n", rows[i].label); fail++; unlink(src); unlink(cs_s); continue; } if (slurp_eq(cs_s, ws_s) != 0) { fprintf(stderr, "row[%s]: cstage/wwstage .s DIFFER (rule-10 " "byte-id violation)\n", rows[i].label); fail++; } unlink(src); unlink(cs_s); unlink(ws_s); } if (fail) { fprintf(stderr, "%d/%d f32-arg-push tests failed\n", fail, n); return 1; } printf("f32arg: %d/%d ok (cstage run + cs==ww byte-id)\n", n, n); return 0; }