/*	$OpenBSD: test_preemption_float.c,v 1.3 2000/01/06 06:58:34 d Exp $	*/
/* Test to see if floating point state is being properly maintained
   for each thread.  Different threads doing floating point operations
   simultaneously should not interfere with one another.  This
   includes operations that might change some FPU flags, such as
   rounding modes, at least implicitly.  */

#include <pthread.h>
#include <math.h>
#include <stdio.h>
#include "test.h"

int limit = 2;
int float_passed = 0;
int float_failed = 1;

void *log_loop (void *x) {
  int i;
  double d, d1, d2;
  /* sleep (1); */
  for (i = 0; i < limit; i++) {
    d = 42.0;
    d = log (exp (d));
    d = (d + 39.0) / d;
    if (i == 0)
      d1 = d;
    else {
		d2 = d;
		d = sin(d);
		/* if (d2 != d1) { */
		if (memcmp (&d2, &d1, 8)) {
			pthread_exit(&float_failed);
		}
	}
  }
  pthread_exit(&float_passed);
}

void *trig_loop (void *x) {
  int i;
  double d, d1, d2;
  /* sleep (1);  */
  for (i = 0; i < limit; i++) {
    d = 35.0;
    d *= M_PI;
    d /= M_LN2;
    d = sin (d);
    d = cos (1 / d);
    if (i == 0)
      d1 = d;
    else {
		d2 = d;
		d = sin(d);
		/* if (d2 != d1) { */
		if (memcmp (&d2, &d1, 8)) {
  			pthread_exit(&float_failed);
		}
	}
  }
  pthread_exit(&float_passed);
}

int
floatloop(pthread_attr_t *attrp)
{
	pthread_t thread[2];
	int *x, *y;

	CHECKr(pthread_create (&thread[0], attrp, trig_loop, 0));
	CHECKr(pthread_create (&thread[1], attrp, log_loop, 0));
	CHECKr(pthread_join(thread[0], (void **) &x));	
	CHECKr(pthread_join(thread[1], (void **) &y));	

	/* Return 0 for success */
	return ((*y == float_failed)?2:0) | 
	       ((*x == float_failed)?1:0);
}

#define N 10
int
main()
{
	pthread_attr_t attr;
	int i;

	/* Try with float point state not preserved */

	CHECKr(pthread_attr_init(&attr));
	CHECKr(pthread_attr_setfloatstate(&attr, PTHREAD_NOFLOAT));

	for(limit = 2; limit < 100000; limit *=4)
		if (floatloop(&attr) != 0)
			break;

	if (limit >= 100000) {
		printf("results are INDETERMINATE\n");
		SUCCEED; /* XXX */
	}

	limit *= 4;  /* just to make sure */

	printf("using limit = %d\n", limit);

	for (i = 0; i < 32; i++) {
		/* Try the failure mode one more time. */
		if (floatloop(&attr) == 0) {
			printf("%d ", i);
			fflush(stdout);
		}
		/* Now see if saving float state will get rid of failure. */
		ASSERT(floatloop(NULL) == 0);
	}

	SUCCEED;
}