1 /* $OpenBSD: rem_test.c,v 1.1 2021/10/22 18:00:23 mbuhl Exp $ */ 2 /*- 3 * Copyright (c) 2005-2008 David Schultz <das@FreeBSD.org> 4 * 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include "macros.h" 29 30 /* 31 * Test for remainder functions: remainder, remainderf, remainderl, 32 * remquo, remquof, and remquol. 33 * Missing tests: fmod, fmodf. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <float.h> 40 #include <math.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <strings.h> 44 45 #include "test-utils.h" 46 47 static void test_invalid(long double, long double); 48 static void testl(long double, long double, long double, int); 49 static void testd(double, double, double, int); 50 static void testf(float, float, float, int); 51 52 #define test(x, y, e_r, e_q) do { \ 53 testl(x, y, e_r, e_q); \ 54 testd(x, y, e_r, e_q); \ 55 testf(x, y, e_r, e_q); \ 56 } while (0) 57 58 ATF_TC_WITHOUT_HEAD(rem1); 59 ATF_TC_BODY(rem1, tc) 60 { 61 test_invalid(0.0, 0.0); 62 test_invalid(1.0, 0.0); 63 test_invalid(INFINITY, 0.0); 64 test_invalid(INFINITY, 1.0); 65 test_invalid(-INFINITY, 1.0); 66 test_invalid(NAN, 1.0); 67 test_invalid(1.0, NAN); 68 69 test(4, 4, 0, 1); 70 test(0, 3.0, 0, 0); 71 testd(0x1p-1074, 1, 0x1p-1074, 0); 72 testf(0x1p-149, 1, 0x1p-149, 0); 73 test(3.0, 4, -1, 1); 74 test(3.0, -4, -1, -1); 75 testd(275 * 1193040, 275, 0, 1193040); 76 test(4.5 * 7.5, 4.5, -2.25, 8); /* we should get the even one */ 77 testf(0x1.9044f6p-1, 0x1.ce662ep-1, -0x1.f109cp-4, 1); 78 #if LDBL_MANT_DIG > 53 79 testl(-0x1.23456789abcdefp-2000L, 0x1.fedcba987654321p-2000L, 80 0x1.b72ea61d950c862p-2001L, -1); 81 #endif 82 } 83 84 ATF_TC_WITHOUT_HEAD(rem2); 85 ATF_TC_BODY(rem2, tc) 86 { 87 /* 88 * The actual quotient here is 864062210.50000003..., but 89 * double-precision division gets -8.64062210.5, which rounds 90 * the wrong way. This test ensures that remquo() is smart 91 * enough to get the low-order bit right. 92 */ 93 testd(-0x1.98260f22fc6dep-302, 0x1.fb3167c430a13p-332, 94 0x1.fb3165b82de72p-333, -864062211); 95 /* Even harder cases with greater exponent separation */ 96 test(0x1.fp100, 0x1.ep-40, -0x1.cp-41, 143165577); 97 testd(-0x1.abcdefp120, 0x1.87654321p-120, -0x1.69c78ec4p-121, 98 -63816414); 99 } 100 101 ATF_TC_WITHOUT_HEAD(rem3); 102 ATF_TC_BODY(rem3, tc) 103 { 104 test(0x1.66666cp+120, 0x1p+71, 0.0, 1476395008); 105 testd(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1); 106 testl(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1); 107 testd(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189); 108 testl(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189); 109 } 110 111 static void 112 test_invalid(long double x, long double y) 113 { 114 int q; 115 116 q = 0xdeadbeef; 117 118 ATF_CHECK(isnan(remainder(x, y))); 119 ATF_CHECK(isnan(remquo(x, y, &q))); 120 #ifdef STRICT 121 ATF_CHECK(q == 0xdeadbeef); 122 #endif 123 124 ATF_CHECK(isnan(remainderf(x, y))); 125 ATF_CHECK(isnan(remquof(x, y, &q))); 126 #ifdef STRICT 127 ATF_CHECK(q == 0xdeadbeef); 128 #endif 129 130 ATF_CHECK(isnan(remainderl(x, y))); 131 ATF_CHECK(isnan(remquol(x, y, &q))); 132 #ifdef STRICT 133 ATF_CHECK(q == 0xdeadbeef); 134 #endif 135 } 136 137 /* 0x012345 ==> 0x01ffff */ 138 static inline int 139 mask(int x) 140 { 141 return ((unsigned)~0 >> (32 - fls(x))); 142 } 143 144 static void 145 testl(long double x, long double y, long double expected_rem, int expected_quo) 146 { 147 int q; 148 long double rem; 149 150 q = random(); 151 rem = remainderl(x, y); 152 ATF_CHECK(rem == expected_rem); 153 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 154 rem = remquol(x, y, &q); 155 ATF_CHECK(rem == expected_rem); 156 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 157 ATF_CHECK((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 158 ATF_CHECK((q & 0x7) == (expected_quo & 0x7)); 159 if (q != 0) { 160 ATF_CHECK((q > 0) ^ !(expected_quo > 0)); 161 q = abs(q); 162 ATF_CHECK(q == (abs(expected_quo) & mask(q))); 163 } 164 } 165 166 static void 167 testd(double x, double y, double expected_rem, int expected_quo) 168 { 169 int q; 170 double rem; 171 172 q = random(); 173 rem = remainder(x, y); 174 ATF_CHECK(rem == expected_rem); 175 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 176 rem = remquo(x, y, &q); 177 ATF_CHECK(rem == expected_rem); 178 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 179 ATF_CHECK((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 180 ATF_CHECK((q & 0x7) == (expected_quo & 0x7)); 181 if (q != 0) { 182 ATF_CHECK((q > 0) ^ !(expected_quo > 0)); 183 q = abs(q); 184 ATF_CHECK(q == (abs(expected_quo) & mask(q))); 185 } 186 } 187 188 static void 189 testf(float x, float y, float expected_rem, int expected_quo) 190 { 191 int q; 192 float rem; 193 194 q = random(); 195 rem = remainderf(x, y); 196 ATF_CHECK(rem == expected_rem); 197 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 198 rem = remquof(x, y, &q); 199 ATF_CHECK(rem == expected_rem); 200 ATF_CHECK(!signbit(rem) == !signbit(expected_rem)); 201 ATF_CHECK((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */ 202 ATF_CHECK((q & 0x7) == (expected_quo & 0x7)); 203 if (q != 0) { 204 ATF_CHECK((q > 0) ^ !(expected_quo > 0)); 205 q = abs(q); 206 ATF_CHECK((q & mask(q)) == (abs(expected_quo) & mask(q))); 207 } 208 } 209 210 ATF_TP_ADD_TCS(tp) 211 { 212 ATF_TP_ADD_TC(tp, rem1); 213 ATF_TP_ADD_TC(tp, rem2); 214 ATF_TP_ADD_TC(tp, rem3); 215 216 return (atf_no_error()); 217 } 218