ww/test/wcc/824_inferred_float_global.c

/*
 * 824_inferred_float_global — an inferred-type (annotation-less) module-global
 * `let pi = 3.5;` whose init is a FLOAT literal must load as a float (MOVSD)
 * at every downstream read, exactly as the explicit-typed `let pi: f64 = 3.5`
 * does. WWSTAGE-ONLY bug (cstage already correct post-#150-B / #18).
 *
 * Root (selfhost/cmd/wcc/cgen.ww): the checker backfills the inferred decl's
 * type annotation to the literal's type node `untyped_float` (check.ww
 * checkletassign). letemitsize keys global slot-sizing on letscalarprim /
 * letfloatprim, NEITHER of which recognises `untyped_float` → returns 0 → the
 * global is DROPPED from collectlets: no DATAW slot emitted, and every read
 * falls through cgident's `isletvar` guard to the silent bare return, leaving
 * X0 holding a stale spilled value. `let pi = 3.5; (pi * 2.0): int` then
 * computed 2.0*2.0 = 4, not 7 — silent, no diagnostic.
 *
 * defaultinferredlets already type_defaults an inferred-INT global's
 * `untyped_int` annotation to the machine word `int`; its comment explicitly
 * carved the float twin out and deferred it to #135, because cstage USED to
 * integer-type an inferred float at the use site (MOVQ) so defaulting ww-side
 * alone would diverge (cs≠ww, rule-10). #150-B fixed cstage to type_default
 * `untyped_float` → f64 and load MOVSD, so the divergence is gone: this commit
 * flips the carve-out (default `untyped_float` → f64, peeling one unary +/- as
 * the int arm does) and adds a name-keyword fallback to cgident's let-float
 * gate (the renamed `f64`/`f32` N_TNAME carries no stamped tinfo cgen can read,
 * so isfloattype's stamp-read misses it; letfloatprim on the keyword fires).
 * wwstage now emits the IDENTICAL `LEAQ main.pi(SB); MOVSD (CX), X0` as cstage.
 *
 *   row         | shape                                       | want
 *   ------------+---------------------------------------------+-----
 *   infer_mul   | let pi = 3.5; (pi * 2.0): int   (the bug)   | 7
 *   infer_read  | let r = 2.5; (r + 0.5): int                 | 3
 *   infer_neg   | let g = -2.5; (g * -2.0): int  (unary peel) | 5
 *   infer_f32   | let q = 1.5f32; (q + 1.5f32): int  (MOVSS)  | 3
 *   ctrl_expl   | let e: f64 = 3.5; (e * 2.0): int (explicit) | 7
 *   ctrl_int    | let n = 5; (n + 1): int    (int stays MOVQ) | 6
 *
 * Pre-fix the infer_* rows ran wwstage=garbage (stale X0 / dropped global) and
 * cstage=correct (cs≠ww); post-fix all six are byte-identical between stages.
 * ctrl_int guards that the inferred-INT default (untyped_int → int, MOVQ) is
 * untouched; ctrl_expl guards the explicit-f64 path didn't regress.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

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; };

static const struct row rows[] = {
	/* infer_mul — the bug: inferred float global read in a float binop,
	 * cast to int. Pre-fix wwstage dropped main.pi (no DATAW) and left X0
	 * stale → 2.0*2.0 = 4; cstage 7. */
	{ "infer_mul",
	  "package main;\n"
	  "let pi = 3.5;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (pi * 2.0): i32;\n"
	  "};\n",
	  7 },

	/* infer_read — second inferred-float read shape (+, not *). */
	{ "infer_read",
	  "package main;\n"
	  "let r = 2.5;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (r + 0.5): i32;\n"
	  "};\n",
	  3 },

	/* infer_neg — inferred float global with a unary-minus init; exercises
	 * defaultinferredlets' single-unary peel (mirror of the int arm). */
	{ "infer_neg",
	  "package main;\n"
	  "let g = -2.5;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (g * -2.0): i32;\n"
	  "};\n",
	  5 },

	/* infer_f32 — a bare f32-suffixed literal infers f32; the float load
	 * must pick MOVSS, not MOVSD. (f32 already worked via letfloatprim's
	 * "f32"; row guards the suffix-inferred path stays MOVSS.) */
	{ "infer_f32",
	  "package main;\n"
	  "let q = 1.5f32;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (q + 1.5f32): i32;\n"
	  "};\n",
	  3 },

	/* ctrl_expl — explicit f64 annotation; already worked (lv.tnode is the
	 * non-nil f64 node). No-regress guard. */
	{ "ctrl_expl",
	  "package main;\n"
	  "let e: f64 = 3.5;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (e * 2.0): i32;\n"
	  "};\n",
	  7 },

	/* ctrl_int — inferred INT global. defaultinferredlets defaults it to
	 * `int` (MOVQ scalar load); the float arm must NOT pull it into MOVSD.
	 * No-regress guard for the int path. */
	{ "ctrl_int",
	  "package main;\n"
	  "let n = 5;\n"
	  "export fn main() i32 = {\n"
	  "\treturn (n + 1): i32;\n"
	  "};\n",
	  6 },
};

static int
run_driver(const char *driver, const struct row *r, int i)
{
	char src[64], tmpdir[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/ifg_%d_%d.ww", getpid(), i);
	snprintf(tmpdir, sizeof tmpdir, "/tmp/ifg_%d_d_%d", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -1;
	fputs(r->src, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: build via %s failed\n",
		    r->label, driver);
		unlink(src); rmdir(tmpdir);
		return -1;
	}

	const char *base = strrchr(src, '/');
	base = base ? base + 1 : src;
	char outbin[128];
	snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
	char *dot = strrchr(outbin, '.');
	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
	int got = runwait(outbin);

	unlink(src); unlink(outbin); rmdir(tmpdir);
	return got;
}

/* asm_byte_identical — w6c vs w6c_ww .s for the same source must match. */
static int
asm_byte_identical(const char *bin, const struct row *r, int i)
{
	char src[64], cs[64], ws[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/ifg_asm_%d_%d.ww", getpid(), i);
	snprintf(cs,  sizeof cs,  "/tmp/ifg_asm_%d_%d_c.s", getpid(), i);
	snprintf(ws,  sizeof ws,  "/tmp/ifg_asm_%d_%d_w.s", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -1;
	fputs(r->src, f);
	fclose(f);

	snprintf(cmd, sizeof cmd, "%s/w6c -o %s %s 2>/dev/null", bin, cs, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: w6c errored\n", r->label);
		unlink(src);
		return -1;
	}
	snprintf(cmd, sizeof cmd, "%s/w6c_ww -o %s %s 2>/dev/null",
	    bin, ws, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: w6c_ww errored\n", r->label);
		unlink(src); unlink(cs);
		return -1;
	}

	FILE *fc = fopen(cs, "rb");
	FILE *fw = fopen(ws, "rb");
	int rc = 0;
	if (!fc || !fw) {
		rc = -1;
	} else {
		for (;;) {
			int a = fgetc(fc);
			int b = fgetc(fw);
			if (a != b) { rc = -1; break; }
			if (a == EOF) break;
		}
	}
	if (fc) fclose(fc);
	if (fw) fclose(fw);
	if (rc != 0)
		fprintf(stderr, "row[%s]: cstage vs wwstage asm differs\n",
		    r->label);
	unlink(src); unlink(cs); unlink(ws);
	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 cdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	char wdrv[1024];
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	struct { const char *name; const char *path; int gated_on_existence; }
	drivers[] = {
		{ "cstage",  cdrv, 0 },
		{ "wwstage", wdrv, 1 },
		{ NULL, NULL, 0 },
	};

	int n = (int)(sizeof rows / sizeof rows[0]);
	int total = 0, fail = 0;

	for (int d = 0; drivers[d].name; d++) {
		if (drivers[d].gated_on_existence
		    && access(drivers[d].path, X_OK) != 0) {
			fprintf(stderr, "inferred_float_global: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].path);
			continue;
		}
		for (int i = 0; i < n; i++) {
			int got = run_driver(drivers[d].path, &rows[i], i);
			total++;
			if (got != rows[i].want) {
				fprintf(stderr,
				    "inferred_float_global[%s][%s]: exit=%d want=%d\n",
				    drivers[d].name, rows[i].label,
				    got, rows[i].want);
				fail++;
			}
		}
	}

	if (access(wdrv, X_OK) == 0) {
		for (int i = 0; i < n; i++) {
			total++;
			if (asm_byte_identical(bin, &rows[i], i) != 0)
				fail++;
		}
	}

	if (fail) {
		fprintf(stderr,
		    "inferred_float_global: %d/%d fixtures failed\n", fail, total);
		return 1;
	}
	printf("inferred_float_global: %d/%d ok\n", total, total);
	return 0;
}