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-rw-r--r--gnulib-tests/test-signbit.c187
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diff --git a/gnulib-tests/test-signbit.c b/gnulib-tests/test-signbit.c
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+++ b/gnulib-tests/test-signbit.c
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+/* Test of signbit() substitute.
+ Copyright (C) 2007-2022 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
+
+#include <config.h>
+
+#include <math.h>
+
+/* signbit must be a macro. */
+#ifndef signbit
+# error missing declaration
+#endif
+
+#include <float.h>
+#include <limits.h>
+
+#include "minus-zero.h"
+#include "infinity.h"
+#include "macros.h"
+
+float zerof = 0.0f;
+double zerod = 0.0;
+long double zerol = 0.0L;
+
+static void
+test_signbitf ()
+{
+ /* Finite values. */
+ ASSERT (!signbit (3.141f));
+ ASSERT (!signbit (3.141e30f));
+ ASSERT (!signbit (3.141e-30f));
+ ASSERT (signbit (-2.718f));
+ ASSERT (signbit (-2.718e30f));
+ ASSERT (signbit (-2.718e-30f));
+ /* Zeros. */
+ ASSERT (!signbit (0.0f));
+ if (1.0f / minus_zerof < 0)
+ ASSERT (signbit (minus_zerof));
+ else
+ ASSERT (!signbit (minus_zerof));
+ /* Infinite values. */
+ ASSERT (!signbit (Infinityf ()));
+ ASSERT (signbit (- Infinityf ()));
+ /* Quiet NaN. */
+ (void) signbit (zerof / zerof);
+#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
+ /* Signalling NaN. */
+ {
+ #define NWORDS \
+ ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+ typedef union { float value; unsigned int word[NWORDS]; } memory_float;
+ memory_float m;
+ m.value = zerof / zerof;
+# if FLT_EXPBIT0_BIT > 0
+ m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
+# else
+ m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
+ ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
+# endif
+ if (FLT_EXPBIT0_WORD < NWORDS / 2)
+ m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
+ else
+ m.word[0] |= (unsigned int) 1;
+ (void) signbit (m.value);
+ #undef NWORDS
+ }
+#endif
+}
+
+static void
+test_signbitd ()
+{
+ /* Finite values. */
+ ASSERT (!signbit (3.141));
+ ASSERT (!signbit (3.141e30));
+ ASSERT (!signbit (3.141e-30));
+ ASSERT (signbit (-2.718));
+ ASSERT (signbit (-2.718e30));
+ ASSERT (signbit (-2.718e-30));
+ /* Zeros. */
+ ASSERT (!signbit (0.0));
+ if (1.0 / minus_zerod < 0)
+ ASSERT (signbit (minus_zerod));
+ else
+ ASSERT (!signbit (minus_zerod));
+ /* Infinite values. */
+ ASSERT (!signbit (Infinityd ()));
+ ASSERT (signbit (- Infinityd ()));
+ /* Quiet NaN. */
+ (void) signbit (zerod / zerod);
+#if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
+ /* Signalling NaN. */
+ {
+ #define NWORDS \
+ ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+ typedef union { double value; unsigned int word[NWORDS]; } memory_double;
+ memory_double m;
+ m.value = zerod / zerod;
+# if DBL_EXPBIT0_BIT > 0
+ m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
+# else
+ m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
+ ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
+# endif
+ m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
+ |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
+ (void) signbit (m.value);
+ #undef NWORDS
+ }
+#endif
+}
+
+static void
+test_signbitl ()
+{
+ /* Finite values. */
+ ASSERT (!signbit (3.141L));
+ ASSERT (!signbit (3.141e30L));
+ ASSERT (!signbit (3.141e-30L));
+ ASSERT (signbit (-2.718L));
+ ASSERT (signbit (-2.718e30L));
+ ASSERT (signbit (-2.718e-30L));
+ /* Zeros. */
+ ASSERT (!signbit (0.0L));
+ if (1.0L / minus_zerol < 0)
+ ASSERT (signbit (minus_zerol));
+ else
+ ASSERT (!signbit (minus_zerol));
+ /* Infinite values. */
+ ASSERT (!signbit (Infinityl ()));
+ ASSERT (signbit (- Infinityl ()));
+ /* Quiet NaN. */
+ (void) signbit (zerol / zerol);
+#if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
+ /* Signalling NaN. */
+ {
+ #define NWORDS \
+ ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+ typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
+
+#if defined __powerpc__ && LDBL_MANT_DIG == 106
+ /* This is PowerPC "double double", a pair of two doubles. Inf and Nan are
+ represented as the corresponding 64-bit IEEE values in the first double;
+ the second is ignored. Manipulate only the first double. */
+ #undef NWORDS
+ #define NWORDS \
+ ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+#endif
+
+ memory_long_double m;
+ m.value = zerol / zerol;
+# if LDBL_EXPBIT0_BIT > 0
+ m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
+# else
+ m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
+ ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
+# endif
+ m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
+ |= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
+ (void) signbit (m.value);
+ #undef NWORDS
+ }
+#endif
+}
+
+int
+main ()
+{
+ test_signbitf ();
+ test_signbitd ();
+ test_signbitl ();
+ return 0;
+}