1 /* Test of multiplying a 'long double' by a power of 2.
2 Copyright (C) 2007-2009 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
28 #include "isnanl-nolibm.h"
30 #define ASSERT(expr) \
35 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
42 /* On HP-UX 10.20, negating 0.0L does not yield -0.0L.
43 So we use minus_zero instead.
44 IRIX cc can't put -0.0L into .data, but can compute at runtime.
45 Note that the expression -LDBL_MIN * LDBL_MIN does not work on other
46 platforms, such as when cross-compiling to PowerPC on MacOS X 10.5. */
47 #if defined __hpux || defined __sgi
49 compute_minus_zero (void)
51 return -LDBL_MIN * LDBL_MIN;
53 # define minus_zero compute_minus_zero ()
55 long double minus_zero = -0.0L;
64 DECL_LONG_DOUBLE_ROUNDING
66 BEGIN_LONG_DOUBLE_ROUNDING ();
70 y = ldexpl (x, 0); ASSERT (isnanl (y));
71 y = ldexpl (x, 5); ASSERT (isnanl (y));
72 y = ldexpl (x, -5); ASSERT (isnanl (y));
75 { /* Positive infinity. */
77 y = ldexpl (x, 0); ASSERT (y == x);
78 y = ldexpl (x, 5); ASSERT (y == x);
79 y = ldexpl (x, -5); ASSERT (y == x);
82 { /* Negative infinity. */
84 y = ldexpl (x, 0); ASSERT (y == x);
85 y = ldexpl (x, 5); ASSERT (y == x);
86 y = ldexpl (x, -5); ASSERT (y == x);
89 { /* Positive zero. */
91 y = ldexpl (x, 0); ASSERT (y == x); ASSERT (!signbit (x));
92 y = ldexpl (x, 5); ASSERT (y == x); ASSERT (!signbit (x));
93 y = ldexpl (x, -5); ASSERT (y == x); ASSERT (!signbit (x));
96 { /* Negative zero. */
98 y = ldexpl (x, 0); ASSERT (y == x); ASSERT (signbit (x));
99 y = ldexpl (x, 5); ASSERT (y == x); ASSERT (signbit (x));
100 y = ldexpl (x, -5); ASSERT (y == x); ASSERT (signbit (x));
103 { /* Positive finite number. */
105 y = ldexpl (x, 0); ASSERT (y == x);
106 y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
107 y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
110 { /* Negative finite number. */
111 x = -20.085536923187667742L;
112 y = ldexpl (x, 0); ASSERT (y == x);
113 y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
114 y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
117 for (i = 1, x = 1.73205L; i <= LDBL_MAX_EXP; i++, x *= 2.0L)
119 y = ldexpl (x, 0); ASSERT (y == x);
120 y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
121 y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
123 for (i = 1, x = 1.73205L; i >= LDBL_MIN_EXP; i--, x *= 0.5L)
125 y = ldexpl (x, 0); ASSERT (y == x);
126 y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
127 if (i - 5 >= LDBL_MIN_EXP)
129 y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
132 for (; i >= LDBL_MIN_EXP - 100 && x > 0.0L; i--, x *= 0.5L)
134 y = ldexpl (x, 0); ASSERT (y == x);
135 y = ldexpl (x, 5); ASSERT (y == x * 32.0L);