xref: /dragonfly/tools/regression/lib/libm/test-rem.c (revision 7f8c68295613ce24cc71827cf210cb3d1e3bc69b)
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  * $FreeBSD: src/tools/regression/lib/msun/test-rem.c,v 1.6 2013/05/31 00:28:39 svnexp Exp $
27  */
28 
29 /*
30  * Test for remainder functions: remainder, remainderf, remainderl,
31  * remquo, remquof, and remquol.
32  * Missing tests: fmod, fmodf.
33  */
34 
35 #include <assert.h>
36 #include <float.h>
37 #include <math.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <strings.h>
41 
42 static void test_invalid(long double, long double);
43 static void testl(long double, long double, long double, int);
44 static void testd(double, double, double, int);
45 static void testf(float, float, float, int);
46 
47 #define   test(x, y, e_r, e_q) do {     \
48           testl(x, y, e_r, e_q);                  \
49           testd(x, y, e_r, e_q);                  \
50           testf(x, y, e_r, e_q);                  \
51 } while (0)
52 
53 int
main(int argc,char * argv[])54 main(int argc, char *argv[])
55 {
56 
57           printf("1..3\n");
58 
59           test_invalid(0.0, 0.0);
60           test_invalid(1.0, 0.0);
61           test_invalid(INFINITY, 0.0);
62           test_invalid(INFINITY, 1.0);
63           test_invalid(-INFINITY, 1.0);
64           test_invalid(NAN, 1.0);
65           test_invalid(1.0, NAN);
66 
67           test(4, 4, 0, 1);
68           test(0, 3.0, 0, 0);
69           testd(0x1p-1074, 1, 0x1p-1074, 0);
70           testf(0x1p-149, 1, 0x1p-149, 0);
71           test(3.0, 4, -1, 1);
72           test(3.0, -4, -1, -1);
73           testd(275 * 1193040, 275, 0, 1193040);
74           test(4.5 * 7.5, 4.5, -2.25, 8);         /* we should get the even one */
75           testf(0x1.9044f6p-1, 0x1.ce662ep-1, -0x1.f109cp-4, 1);
76 #if LDBL_MANT_DIG > 53
77           testl(-0x1.23456789abcdefp-2000L, 0x1.fedcba987654321p-2000L,
78                 0x1.b72ea61d950c862p-2001L, -1);
79 #endif
80 
81           printf("ok 1 - rem\n");
82 
83           /*
84            * The actual quotient here is 864062210.50000003..., but
85            * double-precision division gets -8.64062210.5, which rounds
86            * the wrong way.  This test ensures that remquo() is smart
87            * enough to get the low-order bit right.
88            */
89           testd(-0x1.98260f22fc6dep-302, 0x1.fb3167c430a13p-332,
90               0x1.fb3165b82de72p-333, -864062211);
91           /* Even harder cases with greater exponent separation */
92           test(0x1.fp100, 0x1.ep-40, -0x1.cp-41, 143165577);
93           testd(-0x1.abcdefp120, 0x1.87654321p-120,
94               -0x1.69c78ec4p-121, -63816414);
95 
96           printf("ok 2 - rem\n");
97 
98           test(0x1.66666cp+120, 0x1p+71, 0.0, 1476395008);
99           testd(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1);
100           testl(-0x1.0000000000003p+0, 0x1.0000000000003p+0, -0.0, -1);
101           testd(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189);
102           testl(-0x1.0000000000001p-749, 0x1.4p-1072, 0x1p-1074, -1288490189);
103 
104           printf("ok 3 - rem\n");
105 
106           return (0);
107 }
108 
109 static void
test_invalid(long double x,long double y)110 test_invalid(long double x, long double y)
111 {
112           int q;
113 
114           q = 0xdeadbeef;
115 
116           assert(isnan(remainder(x, y)));
117           assert(isnan(remquo(x, y, &q)));
118 #ifdef STRICT
119           assert(q == 0xdeadbeef);
120 #endif
121 
122           assert(isnan(remainderf(x, y)));
123           assert(isnan(remquof(x, y, &q)));
124 #ifdef STRICT
125           assert(q == 0xdeadbeef);
126 #endif
127 
128           assert(isnan(remainderl(x, y)));
129           assert(isnan(remquol(x, y, &q)));
130 #ifdef STRICT
131           assert(q == 0xdeadbeef);
132 #endif
133 }
134 
135 /* 0x012345 ==> 0x01ffff */
136 static inline int
mask(int x)137 mask(int x)
138 {
139           return ((unsigned)~0 >> (32 - fls(x)));
140 }
141 
142 static void
testl(long double x,long double y,long double expected_rem,int expected_quo)143 testl(long double x, long double y, long double expected_rem, int expected_quo)
144 {
145           int q;
146           long double rem;
147 
148           q = random();
149           rem = remainderl(x, y);
150           assert(rem == expected_rem);
151           assert(!signbit(rem) == !signbit(expected_rem));
152           rem = remquol(x, y, &q);
153           assert(rem == expected_rem);
154           assert(!signbit(rem) == !signbit(expected_rem));
155           assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */
156           assert((q & 0x7) == (expected_quo & 0x7));
157           if (q != 0) {
158                     assert((q > 0) ^ !(expected_quo > 0));
159                     q = abs(q);
160                     assert(q == (abs(expected_quo) & mask(q)));
161           }
162 }
163 
164 static void
testd(double x,double y,double expected_rem,int expected_quo)165 testd(double x, double y, double expected_rem, int expected_quo)
166 {
167           int q;
168           double rem;
169 
170           q = random();
171           rem = remainder(x, y);
172           assert(rem == expected_rem);
173           assert(!signbit(rem) == !signbit(expected_rem));
174           rem = remquo(x, y, &q);
175           assert(rem == expected_rem);
176           assert(!signbit(rem) == !signbit(expected_rem));
177           assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */
178           assert((q & 0x7) == (expected_quo & 0x7));
179           if (q != 0) {
180                     assert((q > 0) ^ !(expected_quo > 0));
181                     q = abs(q);
182                     assert(q == (abs(expected_quo) & mask(q)));
183           }
184 }
185 
186 static void
testf(float x,float y,float expected_rem,int expected_quo)187 testf(float x, float y, float expected_rem, int expected_quo)
188 {
189           int q;
190           float rem;
191 
192           q = random();
193           rem = remainderf(x, y);
194           assert(rem == expected_rem);
195           assert(!signbit(rem) == !signbit(expected_rem));
196           rem = remquof(x, y, &q);
197           assert(rem == expected_rem);
198           assert(!signbit(rem) == !signbit(expected_rem));
199           assert((q ^ expected_quo) >= 0); /* sign(q) == sign(expected_quo) */
200           assert((q & 0x7) == (expected_quo & 0x7));
201           if (q != 0) {
202                     assert((q > 0) ^ !(expected_quo > 0));
203                     q = abs(q);
204                     assert((q & mask(q)) == (abs(expected_quo) & mask(q)));
205           }
206 }
207