ww/test/wcc/686_slice_str_global_zero.c

/*
 * 686_slice_str_global_zero — a bare module-level `str` global and a
 * bare `[]u8` slice global emit their 24-byte zero header EXACTLY ONCE,
 * and cstage / wwstage agree byte-for-byte (task #10 part b).
 *
 * The bug (wwstage only): post-#1, size(str) == size(slice) == 24. The
 * emitletdataw str arm and slice arm were sequential `if`s gated on
 * SIZE alone, so both matched a 24-byte bare global and BOTH fired the
 * no-rhs zero fallback — two `DATAW main.g` rows. cstage discriminates
 * on type kind (let_isstr / let_isslice) and emits one. Runtime reads
 * the null header {0,0,0} correctly either way, so the divergence is
 * byte-id-visible only — the asm_byte_identical gate is the real
 * discriminator; the exit-code rows assert correctness is preserved.
 *
 * The fix: emitletdataw's str and slice arms now branch on the declared
 * type kind (letdeclkind, TY_NAMED-peeled, mirroring let_isstr/
 * let_isslice), mutually exclusive, so a 24B global hits one arm.
 *
 *   row              | shape                                  | want
 *   -----------------+----------------------------------------+------
 *   slice_len        | global let g:[]u8;  g.len              | 0
 *   slice_cap        | global let g:[]u8;  g.cap              | 0
 *   slice_ptr_null   | global let g:[]u8;  g.ptr==nil ? 7 : 0 | 7
 *   str_len          | global let s:str;   s.len              | 0
 *   str_ptr_null     | global let s:str;   s.ptr==nil ? 9 : 0 | 9
 */
#include <stdio.h>
#include <stdlib.h>
#include <errno.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[] = {
	{ "slice_len",
	  "package main;\n"
	  "let g: []u8;\n"
	  "export fn main() i32 = { return g.len: i32; };\n",
	  0 },

	{ "slice_cap",
	  "package main;\n"
	  "let g: []u8;\n"
	  "export fn main() i32 = { return g.cap: i32; };\n",
	  0 },

	{ "slice_ptr_null",
	  "package main;\n"
	  "let g: []u8;\n"
	  "export fn main() i32 = {\n"
	  "\tif (g.ptr == nil) { return 7; };\n"
	  "\treturn 0;\n"
	  "};\n",
	  7 },

	{ "str_len",
	  "package main;\n"
	  "let s: str;\n"
	  "export fn main() i32 = { return s.len: i32; };\n",
	  0 },

	{ "str_ptr_null",
	  "package main;\n"
	  "let s: str;\n"
	  "export fn main() i32 = {\n"
	  "\tif (s.ptr == nil) { return 9; };\n"
	  "\treturn 0;\n"
	  "};\n",
	  9 },
};

static int
run_driver(const char *driver, const struct row *r, int i)
{
	char src[128], tmpdir[64], outbin[128], scratch[160], rmcmd[192], cmd[1024];
	int result = -1, cleanfail = 0;
	snprintf(tmpdir, sizeof tmpdir, "/tmp/ssgz_%d_d_%d", getpid(), i);
	if (mkdir(tmpdir, 0755) != 0) return -1;
	snprintf(src, sizeof src, "%s/ssgz_%d_%d.ww", tmpdir, getpid(), i);
	snprintf(outbin, sizeof outbin, "%s/ssgz_%d_%d", tmpdir, getpid(), i);
	snprintf(scratch, sizeof scratch, "%s.sepwork", outbin);

	FILE *f = fopen(src, "wb");
	if (!f) goto cleanup;
	int writefail = fputs(r->src, f) == EOF;
	if (fclose(f) != 0) writefail = 1;
	if (writefail) goto cleanup;

	snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null",
	    driver, outbin, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: build via %s failed\n",
		    r->label, driver);
		goto cleanup;
	}
	result = runwait(outbin);
cleanup:
	snprintf(rmcmd, sizeof rmcmd, "rm -rf -- %s", scratch);
	if (runwait(rmcmd) != 0) cleanfail = 1;
	if (unlink(src) != 0 && errno != ENOENT) cleanfail = 1;
	if (unlink(outbin) != 0 && errno != ENOENT) cleanfail = 1;
	if (rmdir(tmpdir) != 0) cleanfail = 1;
	if (cleanfail) {
		fprintf(stderr, "row[%s]: temporary cleanup failed\n", r->label);
		if (result == r->want) return -1;
	}
	return result;
}

/* asm_byte_identical — w6c vs w6c_ww .s for the same source must match.
 * This is the #10-part-b discriminator: the old size-keyed double-emit
 * produced a second DATAW row in the wwstage .s. */
static int
asm_byte_identical(const char *bin, const struct row *r, int i)
{
	char tmpdir[64], src[96], cs[96], ws[96], cmd[1024];
	int rc = -1, cleanfail = 0;
	snprintf(tmpdir, sizeof tmpdir, "/tmp/ssgz_asm_%d_%d", getpid(), i);
	if (mkdir(tmpdir, 0755) != 0) return -1;
	snprintf(src, sizeof src, "%s/t.ww", tmpdir);
	snprintf(cs,  sizeof cs,  "%s/c.s", tmpdir);
	snprintf(ws,  sizeof ws,  "%s/w.s", tmpdir);

	FILE *f = fopen(src, "wb");
	if (!f) goto cleanup;
	int writefail = fputs(r->src, f) == EOF;
	if (fclose(f) != 0) writefail = 1;
	if (writefail) goto cleanup;

	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);
		goto cleanup;
	}
	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);
		goto cleanup;
	}

	FILE *fc = fopen(cs, "rb");
	FILE *fw = fopen(ws, "rb");
	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);
cleanup:
	if (unlink(src) != 0 && errno != ENOENT) cleanfail = 1;
	if (unlink(cs) != 0 && errno != ENOENT) cleanfail = 1;
	if (unlink(ws) != 0 && errno != ENOENT) cleanfail = 1;
	if (rmdir(tmpdir) != 0) cleanfail = 1;
	if (cleanfail) {
		fprintf(stderr, "row[%s]: temporary cleanup failed\n", r->label);
		return -1;
	}
	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, "slice_str_global_zero: 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,
				    "slice_str_global_zero[%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,
		    "slice_str_global_zero: %d/%d fixtures failed\n",
		    fail, total);
		return 1;
	}
	printf("slice_str_global_zero: %d/%d ok\n", total, total);
	return 0;
}