1 /* $OpenBSD: preemption_float.c,v 1.1.1.1 2001/08/15 14:37:12 fgsch Exp $ */ 2 /* 3 * Copyright (c) 1993, 1994, 1995, 1996 by Chris Provenzano and contributors, 4 * proven@mit.edu All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Chris Provenzano, 17 * the University of California, Berkeley, and contributors. 18 * 4. Neither the name of Chris Provenzano, the University, nor the names of 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL CHRIS PROVENZANO, THE REGENTS OR 26 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 28 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 29 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 31 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 32 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 /* Test to see if floating point state is being properly maintained 36 for each thread. Different threads doing floating point operations 37 simultaneously should not interfere with one another. This 38 includes operations that might change some FPU flags, such as 39 rounding modes, at least implicitly. */ 40 41 #include <pthread.h> 42 #include <math.h> 43 #include <stdio.h> 44 #include "test.h" 45 46 int limit = 2; 47 int float_passed = 0; 48 int float_failed = 1; 49 50 void *log_loop (void *x) { 51 int i; 52 double d, d1, d2; 53 /* sleep (1); */ 54 for (i = 0; i < limit; i++) { 55 d = 42.0; 56 d = log (exp (d)); 57 d = (d + 39.0) / d; 58 if (i == 0) 59 d1 = d; 60 else { 61 d2 = d; 62 d = sin(d); 63 /* if (d2 != d1) { */ 64 if (memcmp (&d2, &d1, 8)) { 65 pthread_exit(&float_failed); 66 } 67 } 68 } 69 pthread_exit(&float_passed); 70 } 71 72 void *trig_loop (void *x) { 73 int i; 74 double d, d1, d2; 75 /* sleep (1); */ 76 for (i = 0; i < limit; i++) { 77 d = 35.0; 78 d *= M_PI; 79 d /= M_LN2; 80 d = sin (d); 81 d = cos (1 / d); 82 if (i == 0) 83 d1 = d; 84 else { 85 d2 = d; 86 d = sin(d); 87 /* if (d2 != d1) { */ 88 if (memcmp (&d2, &d1, 8)) { 89 pthread_exit(&float_failed); 90 } 91 } 92 } 93 pthread_exit(&float_passed); 94 } 95 96 int 97 floatloop(pthread_attr_t *attrp) 98 { 99 pthread_t thread[2]; 100 int *x, *y; 101 102 CHECKr(pthread_create (&thread[0], attrp, trig_loop, 0)); 103 CHECKr(pthread_create (&thread[1], attrp, log_loop, 0)); 104 CHECKr(pthread_join(thread[0], (void **) &x)); 105 CHECKr(pthread_join(thread[1], (void **) &y)); 106 107 /* Return 0 for success */ 108 return ((*y == float_failed)?2:0) | 109 ((*x == float_failed)?1:0); 110 } 111 112 #define N 10 113 int 114 main() 115 { 116 pthread_attr_t attr; 117 int i; 118 119 /* Try with float point state not preserved */ 120 121 CHECKr(pthread_attr_init(&attr)); 122 CHECKr(pthread_attr_setfloatstate(&attr, PTHREAD_NOFLOAT)); 123 124 for(limit = 2; limit < 100000; limit *=4) 125 if (floatloop(&attr) != 0) 126 break; 127 128 if (limit >= 100000) { 129 printf("results are INDETERMINATE\n"); 130 SUCCEED; /* XXX */ 131 } 132 133 limit *= 4; /* just to make sure */ 134 135 printf("using limit = %d\n", limit); 136 137 for (i = 0; i < 32; i++) { 138 /* Try the failure mode one more time. */ 139 if (floatloop(&attr) == 0) { 140 printf("%d ", i); 141 fflush(stdout); 142 } 143 /* Now see if saving float state will get rid of failure. */ 144 ASSERT(floatloop(NULL) == 0); 145 } 146 147 SUCCEED; 148 } 149