/* $Id: defer_sig.c,v 1.8 2012/01/15 15:46:58 kostik Exp $ */

#include <sys/types.h>
#include <err.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ucontext.h>
#include <unistd.h>
#if defined(__amd64__) || defined (__i386__)
#define	X86
#include <machine/specialreg.h>
#include <machine/cpufunc.h>
#if defined(__amd64__)
#include <machine/fpu.h>
#endif
#if defined(__i386__)
#include <machine/npx.h>
#endif
#endif

#ifdef X86
static int avx;
#endif

static void
handler(int sig __unused, siginfo_t *si __unused, void *uacp)
{
	ucontext_t *ucp;
	mcontext_t *mcp;
#if defined(__amd64__)
	struct savefpu *savefpu;
	struct savefpu_xstate *xstate;
#elif defined (__i386__)
	struct savexmm *savefpu;
	struct savexmm_xstate *xstate;
#endif
#ifdef X86
	char v[32];
	int i;
#endif

	ucp = uacp;
	mcp = &ucp->uc_mcontext;

#ifdef X86
	if (avx) {
		if ((mcp->mc_flags & _MC_HASFPXSTATE) == 0) {
			warnx("no fpxstate in context, flags %x",
			    mcp->mc_flags);
			abort();
		}
		savefpu = (void *)&mcp->mc_fpstate;
		xstate = (void *)mcp->mc_xfpustate;
		bcopy(&savefpu->sv_xmm[0], &v[0], sizeof(v) / 2);
		bcopy(&xstate->sx_ymm[0], &v[sizeof(v) / 2], sizeof(v) / 2);
		for (i = 0; i < (int)sizeof(v); i++) {
			if (i != v[i])
				errx(1, "i %d v[i] %d", i, v[i]);
		}
	} else {
		if ((mcp->mc_flags & _MC_HASFPXSTATE) != 0) {
			warnx("fpxstate in context but no AVX, flags %x",
			    mcp->mc_flags);
			abort();
		}
	}
#endif
}

static void *
test_thread(void *arg)
{
	pthread_barrier_t *b;
	pthread_key_t key;
#ifdef X86
	char v[32];
	int i;

	if (avx) {
		for (i = 0; i < (int)sizeof(v); i++)
			v[i] = i;
		__asm __volatile("vmovdqu\t%0,%%ymm0" : : "m" (*v));
	}
#endif

	b = arg;
	pthread_barrier_wait(b);

	for (;;) {
		pthread_key_create(&key, NULL);
		pthread_key_delete(key);
	}

	return (NULL);
}

int
main(void)
{
	pthread_t thr;
	struct sigaction sa;
	pthread_barrier_t b;
	int error;
#ifdef X86
	u_int cp[4];

	do_cpuid(1, cp);
	if ((cp[2] & (CPUID2_OSXSAVE | CPUID2_AVX)) == (CPUID2_OSXSAVE |
	    CPUID2_AVX)) {
		avx = 1;
		printf("Detected AVX\n");
	} else
		printf("No AVX detected\n");
#endif

	bzero(&sa, sizeof(sa));
	sa.sa_sigaction = handler;
	sa.sa_flags = SA_SIGINFO;
	if (sigaction(SIGHUP, &sa, NULL) == -1)
		err(1, "sigaction");

	pthread_barrier_init(&b, NULL, 2);

	error = pthread_create(&thr, NULL, test_thread, &b);
	if (error != 0)
		errc(1, error, "pthread_create");

	pthread_barrier_wait(&b);
	for (;;)
		pthread_kill(thr, SIGHUP);

	return (0);
}