ww/test/wcc/989_tupfieldsize_run.c

/*
 * 989_tupfieldsize_run — F7-c4 (#43): a for-range destructure over an
 * array of tuples must stride by the tuple's TRUE size; a slice/str/nested
 * tuple FIELD carries its full width, not the 8B scalar default.
 *
 * THE BUG (cat-A silent miscompile, gate-blind): paramfieldsize
 * (selfhost/cmd/wcc/cgenstmt.ww) — the structural sizer the for-range
 * destructure uses to compute the tuple stride and each field's offset —
 * had no N_TSLICE / N_TTUPLE arm, so a `[]T` tuple-field sized 8 (the
 * default) instead of its 24B header. The #270-1c array-literal guard
 * blocks only the literal CONSTRUCTION; the for-range DESTRUCTURE-READ
 * path is unguarded (ken's oracle refuted "unreachable"). For
 * `[2]([]u8, i64)` the wwstage strode the tuple at 16 / read field-2 at
 * offset 8, vs cstage's 32 / 24 — a cs≠ww divergence (the cat-A
 * signature). cstage's tp->type->size (cmd/w6c/cgen.c N_FORRANGE) reads
 * the true width. THE FIX: add the N_TSLICE arm (tyslicesize() = 24, the
 * slice-header SSoT, rule-13) and the N_TTUPLE arm (sum of 8B-floored
 * element slots, recursive), aligning wwstage UP.
 *
 * NB on the assertion: the slice-field row is pinned cs==ww (MATCH-ONLY),
 * NOT to an absolute value. cstage independently mis-loads a single-word
 * tuple-destructure element (a SEPARATE bug ken flagged out of F7 scope,
 * filed as task #40 — cstage's absolute value is wrong: 40 != 45), so
 * both stages currently land 40, not the arithmetic-expected 45. The
 * #43 fix's job is to remove the cs≠ww STRIDE/OFFSET divergence (40 vs 16
 * → 40 vs 40); pinning cs==ww tracks exactly that and won't false-fail
 * when the separate destructure-load bug is later fixed (both move
 * together). The scalar-tuple control IS correct on both stages, so it
 * also pins the absolute value (no-regression teeth).
 *
 * Tuples are built by whole-tuple element store (`xs[i] = (..)`); the
 * `xs[i].0 = ..` field-store target and the `[[..]]` nested literal are
 * both independently unsupported / #270-1c-blocked (orthogonal).
 *
 * Rows (cstage `ww` always; wwstage `ww_ww` when present; rule-10):
 *   row                | shape                          | assert
 *   -------------------+--------------------------------+----------------
 *   slice_field_tuple  | for(.. [2]([]u8,i64))          | cs==ww  [#43 bug]
 *   scalar_tuple_ctl   | for(.. [2](i64,i64)) = 48      | cs==ww AND == 48
 */
#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_exit;	/* >= 0: also pin the absolute value; -1: cs==ww only */
};

static const struct row rows[] = {
	/* (1) #43 — a []u8 tuple-field sized 8 not 24 → wrong stride/offset.
	 * cs==ww only (cstage's 40≠45 is the separate destructure-load bug). */
	{ "slice_field_tuple",
	  "package main;\n"
	  "export fn main() int = {\n"
	  "	let b0: []u8 = ['a', 'b'];\n"
	  "	let b1: []u8 = ['x', 'y', 'z'];\n"
	  "	let xs: [2]([]u8, i64);\n"
	  "	xs[0] = (b0, 10);\n"
	  "	xs[1] = (b1, 30);\n"
	  "	let sum: i64 = 0;\n"
	  "	for (let (b, n) .. xs) {\n"
	  "		sum = sum + len(b): i64 + n;\n"
	  "	};\n"
	  "	return sum: int;\n"
	  "};\n",
	  -1 },

	/* (2) control — scalar-only tuple (no slice/str field): paramfieldsize
	 * already handled it, so c4 must not regress it. Correct on both stages:
	 * 3+10+5+30 == 48. Pins cs==ww AND the absolute value. */
	{ "scalar_tuple_ctl",
	  "package main;\n"
	  "export fn main() int = {\n"
	  "	let xs: [2](i64, i64);\n"
	  "	xs[0] = (3, 10); xs[1] = (5, 30);\n"
	  "	let sum: i64 = 0;\n"
	  "	for (let (a, b) .. xs) { sum = sum + a + b; };\n"
	  "	return sum: int;\n"
	  "};\n",
	  48 },
};

/* run_build — build+run `src` via `driver`; returns the binary's exit
 * code, or -1 on a build failure. */
static int
run_build(const char *driver, const struct row *r, int i)
{
	char src[64], tmpdir[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/tupfs_%d_%d.ww", getpid(), i);
	snprintf(tmpdir, sizeof tmpdir, "/tmp/tupfs_%d_d_%d", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -2;
	fputs(r->src, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, src);
	int brc = runwait(cmd);

	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 = -1;
	if (brc == 0) got = runwait(outbin);

	unlink(src); unlink(outbin); rmdir(tmpdir);
	return brc == 0 ? got : -1;
}

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], wdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);
	int have_ww = (access(wdrv, X_OK) == 0);

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

	for (int i = 0; i < n; i++) {
		total++;
		int gc = run_build(cdrv, &rows[i], i);
		/* cstage must build+run */
		if (gc < 0) {
			fprintf(stderr, "tupfieldsize_run[cstage][%s]: build/run "
			    "failed (got %d)\n", rows[i].label, gc);
			fail++;
			continue;
		}
		if (rows[i].want_exit >= 0 && gc != rows[i].want_exit) {
			fprintf(stderr, "tupfieldsize_run[cstage][%s]: exit=%d "
			    "want=%d\n", rows[i].label, gc, rows[i].want_exit);
			fail++;
		}
		if (!have_ww) {
			fprintf(stderr, "tupfieldsize_run: skip wwstage (no %s)\n",
			    wdrv);
			continue;
		}
		int gw = run_build(wdrv, &rows[i], i);
		/* rule-10: the cat-A invariant is cs == ww */
		if (gw != gc) {
			fprintf(stderr, "tupfieldsize_run[%s]: cs=%d != ww=%d "
			    "(stride/offset divergence — #43)\n",
			    rows[i].label, gc, gw);
			fail++;
		}
		if (rows[i].want_exit >= 0 && gw != rows[i].want_exit) {
			fprintf(stderr, "tupfieldsize_run[wwstage][%s]: exit=%d "
			    "want=%d\n", rows[i].label, gw, rows[i].want_exit);
			fail++;
		}
	}

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