1 /* Copyright (C) 2004, 2006, 2008, 2009 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #elif defined HAVE_MACHINE_FPU_H
29 /* On Tru64 5.1b, the declaration of fesetround(3) is in <machine/fpu.h>.
30 On NetBSD, this header has to be included along with <sys/types.h>. */
31 # ifdef HAVE_SYS_TYPES_H
32 # include <sys/types.h>
34 # include <machine/fpu.h>
40 #define numberof(x) (sizeof (x) / sizeof ((x)[0]))
45 /* FE constants are defined only where supported, in particular for
46 instance some ARM systems have been seen with only a couple of modes */
47 static const int modes[] = {
66 for (i = 0; i < numberof (modes); i++)
68 /* First iteration is the default rounding mode, ie. no call to
69 fesetround. Subsequent iterations are the FE modes from the
74 fesetround (modes[i]);
78 assert (scm_c_round (0.0) == 0.0);
79 assert (scm_c_round (1.0) == 1.0);
80 assert (scm_c_round (-1.0) == -1.0);
82 assert (scm_c_round (0.5) == 0.0);
83 assert (scm_c_round (1.5) == 2.0);
84 assert (scm_c_round (-1.5) == -2.0);
85 assert (scm_c_round (2.5) == 2.0);
86 assert (scm_c_round (-2.5) == -2.0);
87 assert (scm_c_round (3.5) == 4.0);
88 assert (scm_c_round (-3.5) == -4.0);
90 /* 2^(DBL_MANT_DIG-1)-1+0.5 */
91 x = ldexp (1.0, DBL_MANT_DIG - 1) - 1.0 + 0.5;
92 want = ldexp (1.0, DBL_MANT_DIG - 1);
93 assert (scm_c_round (x) == want);
95 /* -(2^(DBL_MANT_DIG-1)-1+0.5) */
96 x = - (ldexp (1.0, DBL_MANT_DIG - 1) - 1.0 + 0.5);
97 want = - ldexp (1.0, DBL_MANT_DIG - 1);
98 assert (scm_c_round (x) == want);
101 In the past scm_c_round had incorrectly incremented this value, due
102 to the way that x+0.5 would round upwards (in the usual default
103 nearest-even mode on most systems). */
104 x = ldexp (1.0, DBL_MANT_DIG) - 1.0;
105 assert (x == floor (x)); /* should be an integer already */
106 assert (scm_c_round (x) == x); /* scm_c_round should return it unchanged */
108 /* -(2^DBL_MANT_DIG-1) */
109 x = - (ldexp (1.0, DBL_MANT_DIG) - 1.0);
110 assert (x == floor (x)); /* should be an integer already */
111 assert (scm_c_round (x) == x); /* scm_c_round should return it unchanged */
115 assert (scm_c_round (x) == x);
118 In the past scm_c_round had incorrectely gone to the next highest
119 representable value in FE_UPWARD, due to x+0.5 rounding. */
120 x = - ldexp (1.0, 64);
121 assert (scm_c_round (x) == x);
126 tests (void *data, int argc, char **argv)
132 main (int argc, char *argv[])
134 scm_boot_guile (argc, argv, tests, NULL);