ww/test/wcc/989_globfloatstructarg_run.c

/*
 * 989_globfloatstructarg_run — F8-c9 (report-item #31, the EXCEPTION):
 * passing a module-GLOBAL float-bearing struct by value must drain its float
 * eightbytes into the SSE arg regs (X0..), not all-GP.
 *
 * THE BUG (cat-A silent miscompile, align-UP): cgcall's per-arg drain decides
 * the SysV eightbyte class via structfloatclass, but read it from the local
 * slot's tnode ONLY (`if (lc != nil) stfc = structfloatclass(lc.tnode)`). A
 * module-global struct arg (lc==nil) kept stfc=0, so the float eightbytes
 * drained as integers (POPQ into DI/SI) and X0 was never loaded — the callee
 * read its f64 fields from the wrong registers. cstage classifies off the
 * operand TYPE, so it loaded X0 and ran correct — the cat-A divergence.
 *
 * THIS IS THE EXCEPTION among the F8 members: the bug is a float-CLASS
 * decision keyed to a local-only slot, NOT an address-routing fallback — an
 * F7-flavoured stamp/type-keying fix. THE FIX: for a global ident, key
 * structfloatclass off the global's declared tnode (letvartnode), the same
 * classification the local path uses. align ww UP; the .s is byte-identical.
 *
 * Rows (build+run on cstage `ww` and wwstage `ww_ww`; rule-10 — agree+hit;
 * each take() returns 0 iff every field round-trips through the call):
 *   row             | shape                            | want
 *   ----------------+----------------------------------+-----
 *   float_first     | gp:{f:f64,i:i64}={1.5,9}; take    | 0 [#31: f→X0]
 *   int_first       | gp:{i:i64,f:f64}={9,2.5}; take    | 0 [int eb→GP, f→X0]
 *   both_float      | gp:{a:f64,b:f64}={1.5,2.5}; take  | 0 [two SSE eightbytes]
 */
#include <stdio.h>
#include <stdlib.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;
};

static const struct row rows[] = {
	{ "float_first",
	  "package main;\n"
	  "type pair = struct { f: f64, i: i64 };\n"
	  "let gp: pair = pair { f = 1.5, i = 9 };\n"
	  "fn take(p: pair) int = { if (p.f == 1.5 && p.i == 9) { return 0; }; return 2; };\n"
	  "export fn main() int = { return take(gp); };\n",
	  0 },

	{ "int_first",
	  "package main;\n"
	  "type pair = struct { i: i64, f: f64 };\n"
	  "let gp: pair = pair { i = 9, f = 2.5 };\n"
	  "fn take(p: pair) int = { if (p.i == 9 && p.f == 2.5) { return 0; }; return 2; };\n"
	  "export fn main() int = { return take(gp); };\n",
	  0 },

	{ "both_float",
	  "package main;\n"
	  "type pp = struct { a: f64, b: f64 };\n"
	  "let gp: pp = pp { a = 1.5, b = 2.5 };\n"
	  "fn take(p: pp) int = { if (p.a == 1.5 && p.b == 2.5) { return 0; }; return 2; };\n"
	  "export fn main() int = { return take(gp); };\n",
	  0 },
};

/* 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[128], tmpdir[64], outbin[128], rmcmd[160], cmd[1024];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/gfsa_%d_d_%d", getpid(), i);
	mkdir(tmpdir, 0755);
	snprintf(src, sizeof src, "%s/gfsa_%d_%d.ww", tmpdir, getpid(), i);
	snprintf(outbin, sizeof outbin, "%s/gfsa_%d_%d", tmpdir, getpid(), i);
	snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir);

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

	snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null",
	    driver, outbin, src);
	int brc = runwait(cmd);

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

	runwait(rmcmd);
	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);

	struct { const char *name; const char *drv; int gated; }
	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 && access(drivers[d].drv, X_OK) != 0) {
			fprintf(stderr, "globfloatstructarg_run: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].drv);
			continue;
		}
		for (int i = 0; i < n; i++) {
			total++;
			int got = run_build(drivers[d].drv, &rows[i], i);
			if (got != rows[i].want_exit) {
				fprintf(stderr, "globfloatstructarg_run[%s][%s]: "
				    "exit=%d want=%d\n", drivers[d].name,
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
		}
	}

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