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authorBruno Haible <bruno@clisp.org>2008-01-26 15:17:58 +0100
committerBruno Haible <bruno@clisp.org>2008-01-26 15:17:58 +0100
commitb17d7ac7df62c7c7f56fe857ed28151d8b0e4e28 (patch)
treee475661f13bd1c4d0e9aa603f244ecdb967d870f /m4/isnan.m4
parentce8675631414567e50a77fdd43196f5882172ca7 (diff)
downloadgnulib-b17d7ac7df62c7c7f56fe857ed28151d8b0e4e28.tar.gz
Rename isnan, applicable to 'double' only, to isnand.
Diffstat (limited to 'm4/isnan.m4')
-rw-r--r--m4/isnan.m4137
1 files changed, 0 insertions, 137 deletions
diff --git a/m4/isnan.m4 b/m4/isnan.m4
deleted file mode 100644
index de692e69a8..0000000000
--- a/m4/isnan.m4
+++ /dev/null
@@ -1,137 +0,0 @@
-# isnan.m4 serial 2
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
-dnl This file is free software; the Free Software Foundation
-dnl gives unlimited permission to copy and/or distribute it,
-dnl with or without modifications, as long as this notice is preserved.
-
-dnl Check how to get or define isnan() without linking with libm.
-
-AC_DEFUN([gl_FUNC_ISNAN_NO_LIBM],
-[
- AC_CACHE_CHECK([whether isnan(double) can be used without linking with libm],
- [gl_cv_func_isnan_no_libm],
- [
- AC_TRY_LINK([#include <math.h>
- double x;],
- [return isnan (x);],
- [gl_cv_func_isnan_no_libm=yes],
- [gl_cv_func_isnan_no_libm=no])
- ])
- if test $gl_cv_func_isnan_no_libm = yes; then
- AC_DEFINE([HAVE_ISNAN_IN_LIBC], 1,
- [Define if the isnan(double) function is available in libc.])
- else
- AC_LIBOBJ([isnan])
- gl_DOUBLE_EXPONENT_LOCATION
- fi
-])
-
-AC_DEFUN([gl_DOUBLE_EXPONENT_LOCATION],
-[
- AC_CACHE_CHECK([where to find the exponent in a 'double'],
- [gl_cv_cc_double_expbit0],
- [
- AC_TRY_RUN([
-#include <float.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <string.h>
-#define NWORDS \
- ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
-typedef union { double value; unsigned int word[NWORDS]; } memory_double;
-static unsigned int ored_words[NWORDS];
-static unsigned int anded_words[NWORDS];
-static void add_to_ored_words (double x)
-{
- memory_double m;
- size_t i;
- /* Clear it first, in case sizeof (double) < sizeof (memory_double). */
- memset (&m, 0, sizeof (memory_double));
- m.value = x;
- for (i = 0; i < NWORDS; i++)
- {
- ored_words[i] |= m.word[i];
- anded_words[i] &= m.word[i];
- }
-}
-int main ()
-{
- size_t j;
- FILE *fp = fopen ("conftest.out", "w");
- if (fp == NULL)
- return 1;
- for (j = 0; j < NWORDS; j++)
- anded_words[j] = ~ (unsigned int) 0;
- add_to_ored_words (0.25);
- add_to_ored_words (0.5);
- add_to_ored_words (1.0);
- add_to_ored_words (2.0);
- add_to_ored_words (4.0);
- /* Remove bits that are common (e.g. if representation of the first mantissa
- bit is explicit). */
- for (j = 0; j < NWORDS; j++)
- ored_words[j] &= ~anded_words[j];
- /* Now find the nonzero word. */
- for (j = 0; j < NWORDS; j++)
- if (ored_words[j] != 0)
- break;
- if (j < NWORDS)
- {
- size_t i;
- for (i = j + 1; i < NWORDS; i++)
- if (ored_words[i] != 0)
- {
- fprintf (fp, "unknown");
- return (fclose (fp) != 0);
- }
- for (i = 0; ; i++)
- if ((ored_words[j] >> i) & 1)
- {
- fprintf (fp, "word %d bit %d", (int) j, (int) i);
- return (fclose (fp) != 0);
- }
- }
- fprintf (fp, "unknown");
- return (fclose (fp) != 0);
-}
- ],
- [gl_cv_cc_double_expbit0=`cat conftest.out`],
- [gl_cv_cc_double_expbit0="unknown"],
- [
- dnl On ARM, there are two 'double' floating-point formats, used by
- dnl different sets of instructions: The older FPA instructions assume
- dnl that they are stored in big-endian word order, while the words
- dnl (like integer types) are stored in little-endian byte order.
- dnl The newer VFP instructions assume little-endian order consistenly.
- AC_EGREP_CPP([mixed_endianness], [
-#if defined arm || defined __arm || defined __arm__
- mixed_endianness
-#endif
- ],
- [gl_cv_cc_double_expbit0="unknown"],
- [
- pushdef([AC_MSG_CHECKING],[:])dnl
- pushdef([AC_MSG_RESULT],[:])dnl
- pushdef([AC_MSG_RESULT_UNQUOTED],[:])dnl
- AC_C_BIGENDIAN(
- [gl_cv_cc_double_expbit0="word 0 bit 20"],
- [gl_cv_cc_double_expbit0="word 1 bit 20"],
- [gl_cv_cc_double_expbit0="unknown"])
- popdef([AC_MSG_RESULT_UNQUOTED])dnl
- popdef([AC_MSG_RESULT])dnl
- popdef([AC_MSG_CHECKING])dnl
- ])
- ])
- rm -f conftest.out
- ])
- case "$gl_cv_cc_double_expbit0" in
- word*bit*)
- word=`echo "$gl_cv_cc_double_expbit0" | sed -e 's/word //' -e 's/ bit.*//'`
- bit=`echo "$gl_cv_cc_double_expbit0" | sed -e 's/word.*bit //'`
- AC_DEFINE_UNQUOTED([DBL_EXPBIT0_WORD], [$word],
- [Define as the word index where to find the exponent of 'double'.])
- AC_DEFINE_UNQUOTED([DBL_EXPBIT0_BIT], [$bit],
- [Define as the bit index in the word where to find bit 0 of the exponent of 'double'.])
- ;;
- esac
-])