1 /*- 2 * Copyright (c) 2010 David Schultz <das@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/tools/regression/lib/msun/test-nearbyint.c,v 1.2 2011/10/21 06:36:40 das Exp $ 27 */ 28 29 /* 30 * Tests for nearbyint{,f,l}() 31 * 32 * TODO: 33 * - adapt tests for rint(3) 34 * - tests for harder values (more mantissa bits than float) 35 */ 36 37 #include <assert.h> 38 #include <fenv.h> 39 #include <math.h> 40 #include <stdio.h> 41 42 #define ALL_STD_EXCEPT (FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \ 43 FE_OVERFLOW | FE_UNDERFLOW) 44 45 static int testnum; 46 47 static const int rmodes[] = { 48 FE_TONEAREST, FE_DOWNWARD, FE_UPWARD, FE_TOWARDZERO, 49 }; 50 51 static const struct { 52 float in; 53 float out[3]; /* one answer per rounding mode except towardzero */ 54 } tests[] = { 55 /* input output (expected) */ 56 { 0.0, { 0.0, 0.0, 0.0 }}, 57 { 0.5, { 0.0, 0.0, 1.0 }}, 58 { M_PI, { 3.0, 3.0, 4.0 }}, 59 { 65536.5, { 65536, 65536, 65537 }}, 60 { INFINITY, { INFINITY, INFINITY, INFINITY }}, 61 { NAN, { NAN, NAN, NAN }}, 62 }; 63 64 static const int ntests = sizeof(tests) / sizeof(tests[0]); 65 66 /* 67 * Compare d1 and d2 using special rules: NaN == NaN and +0 != -0. 68 * Fail an assertion if they differ. 69 */ 70 static int 71 fpequal(long double d1, long double d2) 72 { 73 74 if (d1 != d2) 75 return (isnan(d1) && isnan(d2)); 76 return (copysignl(1.0, d1) == copysignl(1.0, d2)); 77 } 78 79 /* Get the appropriate result for the current rounding mode. */ 80 static float 81 get_output(int testindex, int rmodeindex, int negative) 82 { 83 double out; 84 85 if (negative) { /* swap downwards and upwards if input is negative */ 86 if (rmodeindex == 1) 87 rmodeindex = 2; 88 else if (rmodeindex == 2) 89 rmodeindex = 1; 90 } 91 if (rmodeindex == 3) /* FE_TOWARDZERO uses the value for downwards */ 92 rmodeindex = 1; 93 out = tests[testindex].out[rmodeindex]; 94 return (negative ? -out : out); 95 } 96 97 static void 98 test_nearby(int testindex) 99 { 100 float in, out; 101 int i; 102 103 for (i = 0; i < sizeof(rmodes) / sizeof(rmodes[0]); i++) { 104 fesetround(rmodes[i]); 105 feclearexcept(ALL_STD_EXCEPT); 106 107 in = tests[testindex].in; 108 out = get_output(testindex, i, 0); 109 assert(fpequal(out, nearbyintf(in))); 110 assert(fpequal(out, nearbyint(in))); 111 assert(fpequal(out, nearbyintl(in))); 112 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 113 114 in = -tests[testindex].in; 115 out = get_output(testindex, i, 1); 116 assert(fpequal(out, nearbyintf(in))); 117 assert(fpequal(out, nearbyint(in))); 118 assert(fpequal(out, nearbyintl(in))); 119 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 120 } 121 122 printf("ok %d\t\t# nearbyint(+%g)\n", testnum++, in); 123 } 124 125 static void 126 test_modf(int testindex) 127 { 128 float in, out; 129 float ipartf, ipart_expected; 130 double ipart; 131 long double ipartl; 132 int i; 133 134 for (i = 0; i < sizeof(rmodes) / sizeof(rmodes[0]); i++) { 135 fesetround(rmodes[i]); 136 feclearexcept(ALL_STD_EXCEPT); 137 138 in = tests[testindex].in; 139 ipart_expected = tests[testindex].out[1]; 140 out = copysignf( 141 isinf(ipart_expected) ? 0.0 : in - ipart_expected, in); 142 ipartl = ipart = ipartf = 42.0; 143 144 assert(fpequal(out, modff(in, &ipartf))); 145 assert(fpequal(ipart_expected, ipartf)); 146 assert(fpequal(out, modf(in, &ipart))); 147 assert(fpequal(ipart_expected, ipart)); 148 assert(fpequal(out, modfl(in, &ipartl))); 149 assert(fpequal(ipart_expected, ipartl)); 150 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 151 152 in = -in; 153 ipart_expected = -ipart_expected; 154 out = -out; 155 ipartl = ipart = ipartf = 42.0; 156 assert(fpequal(out, modff(in, &ipartf))); 157 assert(fpequal(ipart_expected, ipartf)); 158 assert(fpequal(out, modf(in, &ipart))); 159 assert(fpequal(ipart_expected, ipart)); 160 assert(fpequal(out, modfl(in, &ipartl))); 161 assert(fpequal(ipart_expected, ipartl)); 162 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 163 } 164 165 printf("ok %d\t\t# modf(+%g)\n", testnum++, in); 166 } 167 168 int 169 main(int argc, char *argv[]) 170 { 171 int i; 172 173 printf("1..%d\n", ntests * 2); 174 testnum = 1; 175 for (i = 0; i < ntests; i++) { 176 test_nearby(i); 177 test_modf(i); 178 } 179 180 return (0); 181 } 182