/* * 962_opaque_assign_cast_run — runtime + byte-id proof of #108 sub-fold * (c): opaque as a type-erasure sink. Two assignability rules + the * reinterpret casts sort's implementation relies on. * * rule 1 `*T -> *opaque` IMPLICIT (no cast). Any pointer is the * universal void-pointer. harec type_is_assignable, pointer * arm: ref/harec/src/types.c:1053 (`case STORAGE_OPAQUE: * break;` — the referent need not match). * rule 2 `[]T -> []opaque` IMPLICIT (no cast). Any slice is the * type-erased slice; the {ptr,len,cap} header is normal, * the byte stride is supplied at runtime (itemsz). harec * slice arm: types.c:1094 (`if (to_secondary->storage == * STORAGE_OPAQUE) return true;`). * casts `[]opaque -> *u8` (slice -> byte ptr; cgexpr leaves the * ptr in AX, so the cast naturally takes .ptr) and * `*opaque -> *u8` / `*opaque -> *i32` (ptr->ptr reinterpret, * a no-op). drew described the Hare idiom as `*[*]u8`; ww has * no unbounded-array `[*]`, so the ww-faithful reinterpret * target is `*u8` + uintptr stride arithmetic. * * Rule-10 placement (per-rule, empirical): * rules 1 & 2 are CSTAGE-ONLY. cstage type_assignable (cmd/wcc/ * type.c) gained the opaque sink; the wwstage check.ww isassignable * is a resolve-only AST approximation that returns "can't tell, stay * quiet" (confident=false) for a ptr/slice whose element it cannot * match, so it already ACCEPTS every form here (let-init AND call- * arg). Verified empirically: w6c_ww compiles each row's source with * exit 0, byte-identically to w6c (the cs==ww gate below). cstage * rejected these before the type.c change. No ww twin is needed * (same align-down precedent as 960/961's cstage-only arms). * The casts are validation-free in BOTH stages (N_CAST never checks * legality) and the reinterpret cgen needed no change — proven by * the cs==ww byte-id gate. * * Array->[]opaque (harec's array->slice decay, types.c:1080-1099) is * deliberately EXCLUDED: ww has no implicit array->slice conversion for * any element type (`let s: []i32 = a` is rejected too — a slice is * built only via an explicit `a[0:n]`), so there is no array->slice- * header cgen. Accepting array->[]opaque alone would assign a fat * array local into a 24-byte slot with no decay: a silent miscompile * (rule 7). sort's caller passes a slice, so slice->[]opaque suffices. * * opaque is unused by the bootstrap, so the new rules fire only on * opaque-typed operands — INERT on the selfhost corpus, 990-997 stay * byte-identical. But that same inertness means the 990-997 gates * never exercise opaque cs==ww; this test carries its own w6c-vs-w6c_ww * byte-id gate (dimension (b)) to cover the rule-10 symmetry directly. * * Each row carries BOTH dimensions, like 953_f64crossmod_run: * (a) cstage `ww build` + run, asserting the exit code — pins that * the converged asm is runtime-correct (the type erasure round- * trips: a value written/read through the opaque path reads back * intact). * (b) w6c vs w6c_ww `.s` cmp — FAILS if the stages diverge. * * NOTE — call results are bound to locals before any comparison, never * compared inline (`if (f(x) != k)`). That inline-call-result-in- * comparison shape is mis-compiled by a PRE-EXISTING cgen bug (#116 * family: reproduced with zero opaque — a fn-call result compared * inline when its pointer arg was produced by a prior call doing * uintptr arithmetic). Binding first is the same dodge 960 uses; it is * NOT a workaround for the opaque feature, which is exercised in full. */ #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; } 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; } struct row { const char *label; const char *src; int want_exit; }; static const struct row rows[] = { /* rule 1: `*T -> *opaque` IMPLICIT (no cast) at a let-init AND a * call-arg. Round-trip a real *i32 through *opaque and back, deref. */ { "rule1_implicit_ptr", "package main;\n" "fn readi32(p: *opaque) i32 = { let pi: *i32 = p: *i32; return *pi; };\n" "export fn main() i32 = {\n" " let n: i32 = 42;\n" " let po: *opaque = &n;\n" /* let-init *i32 -> *opaque */ " let v: i32 = readi32(po);\n" " let v2: i32 = readi32(&n);\n" /* call-arg *i32 -> *opaque */ " if (v != 42) { return 1; };\n" " if (v2 != 42) { return 2; };\n" " return v;\n" "};\n", 42 }, /* rule 2: `[]T -> []opaque` IMPLICIT (no cast) at a let-init AND a * call-arg. Read .len, round-trip .ptr (a *opaque) back to *i32. */ { "rule2_implicit_slice", "package main;\n" "fn slen(o: []opaque) i32 = { return o.len: i32; };\n" "fn first(o: []opaque) i32 = { let p: *opaque = o.ptr; let pi: *i32 = p: *i32; return *pi; };\n" "export fn main() i32 = {\n" " let a: [4]i32 = [11, 22, 33, 44];\n" " let s: []i32 = a[0:4];\n" " let o: []opaque = s;\n" /* let-init []i32 -> []opaque */ " let n: i32 = slen(o);\n" " let n2: i32 = slen(s);\n" /* call-arg []i32 -> []opaque */ " if (n != 4) { return 1; };\n" " if (n2 != 4) { return 2; };\n" " let f: i32 = first(s);\n" " if (f != 11) { return 3; };\n" " return n;\n" "};\n", 4 }, /* sort's actual usage end-to-end: a `fn(items: []opaque, itemsz: * size)` called with a []i32; inside, reinterpret the slice as a * byte base (`items: *u8`), uintptr-arith two element addresses, * byte-swap them by itemsz. Then read back through the *opaque * element path and through the original []i32 view — the type * erasure round-trips iff both agree. Also a *opaque arg straight * from a *i32 (rule 1). exit 0 == every assertion held. */ { "sort_pattern", "package main;\n" "fn elemptr(items: []opaque, i: size, itemsz: size) *opaque = {\n" " let base: *u8 = items: *u8;\n" /* []opaque -> *u8 (takes .ptr) */ " let off: uintptr = (i * itemsz): uintptr;\n" " return ((base: uintptr) + off): *opaque;\n" "};\n" "fn swap(items: []opaque, x: size, y: size, itemsz: size) void = {\n" " let pa: *u8 = elemptr(items, x, itemsz): *u8;\n" " let pb: *u8 = elemptr(items, y, itemsz): *u8;\n" " let k: size = 0;\n" " for (k < itemsz) {\n" " let qa: *u8 = ((pa: uintptr) + k: uintptr): *u8;\n" " let qb: *u8 = ((pb: uintptr) + k: uintptr): *u8;\n" " let t: u8 = *qa;\n" " *qa = *qb;\n" " *qb = t;\n" " k = k + 1;\n" " };\n" "};\n" "fn readi32(p: *opaque) i32 = { let pi: *i32 = p: *i32; return *pi; };\n" "export fn main() i32 = {\n" " let a: [4]i32 = [10, 20, 30, 40];\n" " let s: []i32 = a[0:4];\n" " swap(s, 0: size, 3: size, size(i32));\n" /* []i32 -> []opaque call-arg */ " if (a[0] != 40) { return 1; };\n" /* erased swap round-trips */ " if (a[3] != 10) { return 2; };\n" " let p0: *opaque = elemptr(s, 0: size, size(i32));\n" " let v0: i32 = readi32(p0);\n" " if (v0 != 40) { return 3; };\n" " let nn: i32 = 77;\n" " let pn: *opaque = &nn;\n" /* *i32 -> *opaque let-init */ " let vn: i32 = readi32(pn);\n" " if (vn != 77) { return 4; };\n" " let o: []opaque = s;\n" " let ol: i32 = o.len: i32;\n" " if (ol != 4) { return 5; };\n" " return 0;\n" "};\n", 0 }, { NULL, NULL, 0 } }; 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, "opaque_assign_cast: w6c_ww missing — cannot " "run the cs==ww byte-id gate (the rule-10 proof)\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/wwopqc_%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 in a scratch dir. */ char tmpdir[64]; snprintf(tmpdir, sizeof tmpdir, "/tmp/wwopqc_%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/wwopqc_%d_%d_cs.s", getpid(), i); snprintf(ws_s, sizeof ws_s, "/tmp/wwopqc_%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 opaque assign/cast tests failed\n", fail, n); return 1; } printf("opaque_assign_cast: %d/%d ok (cstage run + cs==ww byte-id)\n", n, n); return 0; }