1 /*- 2 * Copyright (c) 2005-2008 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 27 /* 28 * Test for remainder functions: remainder, remainderf, remainderl, 29 * remquo, remquof, and remquol. 30 * Missing tests: fmod, fmodf. 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <assert.h> 37 #include <float.h> 38 #include <math.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <strings.h> 42 43 static void test_invalid(long double, long double); 44 static void testl(long double, long double, long double, int); 45 static void testd(double, double, double, int); 46 static void testf(float, float, float, int); 47 48 #define test(x, y, e_r, e_q) do { \ 49 testl(x, y, e_r, e_q); \ 50 testd(x, y, e_r, e_q); \ 51 testf(x, y, e_r, e_q); \ 52 } while (0) 53 54 int 55 main(void) 56 { 57 58 printf("1..3\n"); 59 60 test_invalid(0.0, 0.0); 61 test_invalid(1.0, 0.0); 62 test_invalid(INFINITY, 0.0); 63 test_invalid(INFINITY, 1.0); 64 test_invalid(-INFINITY, 1.0); 65 test_invalid(NAN, 1.0); 66 test_invalid(1.0, NAN); 67 68 test(4, 4, 0, 1); 69 test(0, 3.0, 0, 0); 70 testd(0x1p-1074, 1, 0x1p-1074, 0); 71 testf(0x1p-149, 1, 0x1p-149, 0); 72 test(3.0, 4, -1, 1); 73 test(3.0, -4, -1, -1); 74 testd(275 * 1193040, 275, 0, 1193040); 75 test(4.5 * 7.5, 4.5, -2.25, 8); /* we should get the even one */ 76 testf(0x1.9044f6p-1, 0x1.ce662ep-1, -0x1.f109cp-4, 1); 77 #if LDBL_MANT_DIG > 53 78 testl(-0x1.23456789abcdefp-2000L, 0x1.fedcba987654321p-2000L, 79 0x1.b72ea61d950c862p-2001L, -1); 80 #endif 81 82 printf("ok 1 - rem\n"); 83 84 /* 85 * The actual quotient here is 864062210.50000003..., but 86 * double-precision division gets -8.64062210.5, which rounds 87 * the wrong way. This test ensures that remquo() is smart 88 * enough to get the low-order bit right. 89 */ 90 testd(-0x1.98260f22fc6dep-302, 0x1.fb3167c430a13p-332, 91 0x1.fb3165b82de72p-333, -864062211); 92 /* Even harder cases with greater exponent separation */ 93 test(0x1.fp100, 0x1.ep-40, -0x1.cp-41, 143165577); 94 testd(-0x1.abcdefp120, 0x1.87654321p-120, 95 -0x1.69c78ec4p-121, -63816414); 96 97 printf("ok 2 - rem\n"); 98 99 test(0x1.66666cp+120, 0x1p+71, 0.0, 1476395008); 100 testd(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1); 101 testl(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1); 102 testd(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189); 103 testl(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189); 104 105 printf("ok 3 - rem\n"); 106 107 return (0); 108 } 109 110 static void 111 test_invalid(long double x, long double y) 112 { 113 int q; 114 115 q = 0xdeadbeef; 116 117 assert(isnan(remainder(x, y))); 118 assert(isnan(remquo(x, y, &q))); 119 #ifdef STRICT 120 assert(q == 0xdeadbeef); 121 #endif 122 123 assert(isnan(remainderf(x, y))); 124 assert(isnan(remquof(x, y, &q))); 125 #ifdef STRICT 126 assert(q == 0xdeadbeef); 127 #endif 128 129 assert(isnan(remainderl(x, y))); 130 assert(isnan(remquol(x, y, &q))); 131 #ifdef STRICT 132 assert(q == 0xdeadbeef); 133 #endif 134 } 135 136 /* 0x012345 ==> 0x01ffff */ 137 static inline int 138 mask(int x) 139 { 140 return ((unsigned)~0 >> (32 - fls(x))); 141 } 142 143 static void 144 testl(long double x, long double y, long double expected_rem, int expected_quo) 145 { 146 int q; 147 long double rem; 148 149 q = random(); 150 rem = remainderl(x, y); 151 assert(rem == expected_rem); 152 assert(!signbit(rem) == !signbit(expected_rem)); 153 rem = remquol(x, y, &q); 154 assert(rem == expected_rem); 155 assert(!signbit(rem) == !signbit(expected_rem)); 156 assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 157 assert((q & 0x7) == (expected_quo & 0x7)); 158 if (q != 0) { 159 assert((q > 0) ^ !(expected_quo > 0)); 160 q = abs(q); 161 assert(q == (abs(expected_quo) & mask(q))); 162 } 163 } 164 165 static void 166 testd(double x, double y, double expected_rem, int expected_quo) 167 { 168 int q; 169 double rem; 170 171 q = random(); 172 rem = remainder(x, y); 173 assert(rem == expected_rem); 174 assert(!signbit(rem) == !signbit(expected_rem)); 175 rem = remquo(x, y, &q); 176 assert(rem == expected_rem); 177 assert(!signbit(rem) == !signbit(expected_rem)); 178 assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 179 assert((q & 0x7) == (expected_quo & 0x7)); 180 if (q != 0) { 181 assert((q > 0) ^ !(expected_quo > 0)); 182 q = abs(q); 183 assert(q == (abs(expected_quo) & mask(q))); 184 } 185 } 186 187 static void 188 testf(float x, float y, float expected_rem, int expected_quo) 189 { 190 int q; 191 float rem; 192 193 q = random(); 194 rem = remainderf(x, y); 195 assert(rem == expected_rem); 196 assert(!signbit(rem) == !signbit(expected_rem)); 197 rem = remquof(x, y, &q); 198 assert(rem == expected_rem); 199 assert(!signbit(rem) == !signbit(expected_rem)); 200 assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 201 assert((q & 0x7) == (expected_quo & 0x7)); 202 if (q != 0) { 203 assert((q > 0) ^ !(expected_quo > 0)); 204 q = abs(q); 205 assert((q & mask(q)) == (abs(expected_quo) & mask(q))); 206 } 207 } 208