lib/msun/tests/nearbyint_test.c

   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
  27 /*
  28  * Tests for nearbyint{,f,l}()
  29  *
  30  * TODO:
  31  * - adapt tests for rint(3)
  32  * - tests for harder values (more mantissa bits than float)
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #include <sys/param.h>
  37 #include <fenv.h>
  38 #include <math.h>
  39 #include <stdio.h>
  40
  41 #include "test-utils.h"
  42
  43 static const int rmodes[] = {
  44         FE_TONEAREST, FE_DOWNWARD, FE_UPWARD, FE_TOWARDZERO,
  45 };
  46
  47 /* Make sure we're testing the library, not some broken compiler built-ins. */
  48 static double (*libnearbyint)(double) = nearbyint;
  49 static float (*libnearbyintf)(float) = nearbyintf;
  50 static long double (*libnearbyintl)(long double) = nearbyintl;
  51 #define nearbyintf libnearbyintf
  52 #define nearbyint libnearbyint
  53 #define nearbyintl libnearbyintl
  54
  55 static const struct {
  56         float in;
  57         float out[3];   /* one answer per rounding mode except towardzero */
  58 } tests[] = {
  59 /* input        output (expected) */
  60     { 0.0,      { 0.0, 0.0, 0.0 }},
  61     { 0.5,      { 0.0, 0.0, 1.0 }},
  62     { M_PI,     { 3.0, 3.0, 4.0 }},
  63     { 65536.5,  { 65536, 65536, 65537 }},
  64     { INFINITY, { INFINITY, INFINITY, INFINITY }},
  65     { NAN,      { NAN, NAN, NAN }},
  66 };
  67
  68 /* Get the appropriate result for the current rounding mode. */
  69 static float
  70 get_output(int testindex, int rmodeindex, int negative)
  71 {
  72         double out;
  73
  74         if (negative) { /* swap downwards and upwards if input is negative */
  75                 if (rmodeindex == 1)
  76                         rmodeindex = 2;
  77                 else if (rmodeindex == 2)
  78                         rmodeindex = 1;
  79         }
  80         if (rmodeindex == 3) /* FE_TOWARDZERO uses the value for downwards */
  81                 rmodeindex = 1;
  82         out = tests[testindex].out[rmodeindex];
  83         return (negative ? -out : out);
  84 }
  85
  86 static void
  87 test_nearby(int testindex)
  88 {
  89         float in, out;
  90         unsigned i;
  91
  92         for (i = 0; i < sizeof(rmodes) / sizeof(rmodes[0]); i++) {
  93                 ATF_REQUIRE_EQ(0, fesetround(rmodes[i]));
  94                 ATF_REQUIRE_EQ(0, feclearexcept(ALL_STD_EXCEPT));
  95
  96                 in = tests[testindex].in;
  97                 out = get_output(testindex, i, 0);
  98                 CHECK_FPEQUAL(out, libnearbyintf(in));
  99                 CHECK_FPEQUAL(out, nearbyint(in));
 100                 CHECK_FPEQUAL(out, nearbyintl(in));
 101                 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
 102
 103                 in = -tests[testindex].in;
 104                 out = get_output(testindex, i, 1);
 105                 CHECK_FPEQUAL(out, nearbyintf(in));
 106                 CHECK_FPEQUAL(out, nearbyint(in));
 107                 CHECK_FPEQUAL(out, nearbyintl(in));
 108                 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
 109         }
 110 }
 111
 112 static void
 113 test_modf(int testindex)
 114 {
 115         float in, out;
 116         float ipartf, ipart_expected;
 117         double ipart;
 118         long double ipartl;
 119         unsigned i;
 120
 121         for (i = 0; i < sizeof(rmodes) / sizeof(rmodes[0]); i++) {
 122                 ATF_REQUIRE_EQ(0, fesetround(rmodes[i]));
 123                 ATF_REQUIRE_EQ(0, feclearexcept(ALL_STD_EXCEPT));
 124
 125                 in = tests[testindex].in;
 126                 ipart_expected = tests[testindex].out[1];
 127                 out = copysignf(
 128                     isinf(ipart_expected) ? 0.0 : in - ipart_expected, in);
 129                 ipartl = ipart = ipartf = 42.0;
 130
 131                 CHECK_FPEQUAL(out, modff(in, &ipartf));
 132                 CHECK_FPEQUAL(ipart_expected, ipartf);
 133                 CHECK_FPEQUAL(out, modf(in, &ipart));
 134                 CHECK_FPEQUAL(ipart_expected, ipart);
 135                 CHECK_FPEQUAL(out, modfl(in, &ipartl));
 136                 CHECK_FPEQUAL(ipart_expected, ipartl);
 137                 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
 138
 139                 in = -in;
 140                 ipart_expected = -ipart_expected;
 141                 out = -out;
 142                 ipartl = ipart = ipartf = 42.0;
 143                 CHECK_FPEQUAL(out, modff(in, &ipartf));
 144                 CHECK_FPEQUAL(ipart_expected, ipartf);
 145                 CHECK_FPEQUAL(out, modf(in, &ipart));
 146                 CHECK_FPEQUAL(ipart_expected, ipart);
 147                 CHECK_FPEQUAL(out, modfl(in, &ipartl));
 148                 CHECK_FPEQUAL(ipart_expected, ipartl);
 149                 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
 150         }
 151 }
 152
 153 ATF_TC_WITHOUT_HEAD(nearbyint);
 154 ATF_TC_BODY(nearbyint, tc)
 155 {
 156         unsigned i;
 157
 158         for (i = 0; i < nitems(tests); i++) {
 159                 test_nearby(i);
 160                 test_modf(i);
 161         }
 162 }
 163
 164 ATF_TP_ADD_TCS(tp)
 165 {
 166         ATF_TP_ADD_TC(tp, nearbyint);
 167
 168         return (atf_no_error());
 169 }