/* * 912_sar_shr_run — runtime + byte-id net for #136: signed right-shift * (both plain `>>` and `>>=`) must use SAR (arithmetic, sign-extends * MSB), not SHR (logical, zero-fill). Pre-fix BOTH stages emitted SHRQ * for signed RSHIFT because A_SARQ wasn't in the w6a opcode table, so * `let i: i32 = -200; i >>= 2;` produced i = 0x3FFFFFCE (1073741774) * instead of -50. cs==ww held → gate-blind. #133-expanded shipped with * this pre-existing concern documented (parity with cgen.c:4145 deref- * lvalue compound site); #136 closes it. * * Fix: add A_SARQ to w6a + w6c + w6a_ww opcode tables (encoding REX.W * D3 /7, parallel to SHR's D3 /5), then sweep cgen sites in both * stages to dispatch SARQ vs SHRQ on the operand signedness. Sites * covered (per-stage 6 each): * - plain `>>` binop (cgbin TK_RSHIFT) * - chained-ptr-field compound RSHIFTEQ (#133-expanded site 1) * - N_INDEX-lhs compound RSHIFTEQ (#133-expanded site 2) * - deref-target compound RSHIFTEQ (pre-existing) * - top-level let compound RSHIFTEQ * - IDENT-local compound RSHIFTEQ * * The bootstrap audit at design time showed zero current signed-RSHIFT * callers in lib/+selfhost/, so 990-997 byte-id stays GREEN; the only * shifts are on the previously-broken paths. * * Rows cover the operator + signedness × storage matrix: * - i32_neg_rshifteq: lead's repro pattern, -200 >>= 2 = -50 (was * 1073741774 pre-fix on SHRQ) * - i64_neg_rshifteq: same shape, i64 * - i32_pos_rshifteq: control, SARQ and SHRQ produce same result on * positives; asserts no regression * - u32_rshifteq: unsigned control, must still use SHRQ (no change) * - i32_neg_rshift_binop: plain `>>` (not compound) on negative i32, * covers the cgen 2596 / 3176 TK_RSHIFT N_BIN site * * Each row carries (a) cstage `ww build` + run asserting the exit * code and (b) w6c vs w6c_ww `.s` cmp (rule-10 byte-id). Exit codes * use small absolute values + 256 to encode signed expectations: * -50 → 206 = 256-50 (Unix exit is 8-bit unsigned). i64 row clamped * similarly. */ #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[] = { /* The #136 repro: signed i32 >>=. Pre-fix produced wrong large * positive; post-fix produces -50. Exit code = -50 as u8 = 206. */ { "i32_neg_rshifteq", "package main;\n" "export fn main() i32 = {\n" " let i: i32 = -200;\n" " i >>= 2;\n" " return i;\n" "};\n", 206 }, /* signed i64 >>=. Same shape, wider type. Result -50 as exit u8 * = 206. */ { "i64_neg_rshifteq", "package main;\n" "export fn main() i32 = {\n" " let i: i64 = -200i64;\n" " i >>= 2i64;\n" " return i: i32;\n" "};\n", 206 }, /* Positive control: SARQ and SHRQ agree. 200 >> 2 = 50. */ { "i32_pos_rshifteq", "package main;\n" "export fn main() i32 = {\n" " let i: i32 = 200;\n" " i >>= 2;\n" " return i;\n" "};\n", 50 }, /* Unsigned control: SHRQ unchanged. 200u32 >> 2 = 50. */ { "u32_rshifteq", "package main;\n" "export fn main() i32 = {\n" " let i: u32 = 200u32;\n" " i >>= 2u32;\n" " return i: i32;\n" "};\n", 50 }, /* Plain `>>` (not compound) on signed negative: covers cgbin * TK_RSHIFT site (cgen.c:2596 / cgenexpr.ww:3176). */ { "i32_neg_rshift_binop", "package main;\n" "export fn main() i32 = {\n" " let i: i32 = -200;\n" " let r: i32 = i >> 2;\n" " return r;\n" "};\n", 206 }, { 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, "sarshr: 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/wwsar_%d_%d.ww", getpid(), i); FILE *f = fopen(src, "wb"); if (f == NULL) { fail++; continue; } fputs(rows[i].src, f); fclose(f); char tmpdir[64]; snprintf(tmpdir, sizeof tmpdir, "/tmp/wwsar_%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); char cs_s[64], ws_s[64]; snprintf(cs_s, sizeof cs_s, "/tmp/wwsar_%d_%d_cs.s", getpid(), i); snprintf(ws_s, sizeof ws_s, "/tmp/wwsar_%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 sar/shr tests failed\n", fail, n); return 1; } printf("sarshr: %d/%d ok (cstage run + cs==ww byte-id)\n", n, n); return 0; }