Imported Upstream version 0.9.1upstream/0.9.1

1 files changed, 287 insertions, 0 deletions

diff --git a/gnulib-m4/signbit.m4 b/gnulib-m4/signbit.m4
new file mode 100644
index 00000000..233bf2a3
--- /dev/null
+++ b/gnulib-m4/signbit.m4
@@ -0,0 +1,287 @@
+# signbit.m4 serial 6
+dnl Copyright (C) 2007-2009 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.
+
+AC_DEFUN([gl_SIGNBIT],
+[
+  AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  AC_CACHE_CHECK([for signbit macro], [gl_cv_func_signbit],
+    [
+      AC_TRY_RUN([
+#include <math.h>
+/* If signbit is defined as a function, don't use it, since calling it for
+   'float' or 'long double' arguments would involve conversions.
+   If signbit is not declared at all but exists as a library function, don't
+   use it, since the prototype may not match.
+   If signbit is not declared at all but exists as a compiler built-in, don't
+   use it, since it's preferable to use __builtin_signbit* (no warnings,
+   no conversions).  */
+#ifndef signbit
+# error "signbit should be a macro"
+#endif
+#include <string.h>
+]gl_SIGNBIT_TEST_PROGRAM
+, [gl_cv_func_signbit=yes], [gl_cv_func_signbit=no],
+        [gl_cv_func_signbit="guessing no"])
+    ])
+  dnl GCC 4.0 and newer provides three built-ins for signbit.
+  dnl They can be used without warnings, also in C++, regardless of <math.h>.
+  dnl But they may expand to calls to functions, which may or may not be in
+  dnl libc.
+  AC_CACHE_CHECK([for signbit compiler built-ins], [gl_cv_func_signbit_gcc],
+    [
+      AC_TRY_RUN([
+#if __GNUC__ >= 4
+# define signbit(x) \
+   (sizeof (x) == sizeof (long double) ? __builtin_signbitl (x) : \
+    sizeof (x) == sizeof (double) ? __builtin_signbit (x) : \
+    __builtin_signbitf (x))
+#else
+# error "signbit should be three compiler built-ins"
+#endif
+#include <string.h>
+]gl_SIGNBIT_TEST_PROGRAM
+, [gl_cv_func_signbit_gcc=yes], [gl_cv_func_signbit_gcc=no],
+        [gl_cv_func_signbit_gcc="guessing no"])
+    ])
+  dnl Use the compiler built-ins whenever possible, because they are more
+  dnl efficient than the system library functions (if they exist).
+  if test "$gl_cv_func_signbit_gcc" = yes; then
+    REPLACE_SIGNBIT_USING_GCC=1
+  else
+    if test "$gl_cv_func_signbit" != yes; then
+      REPLACE_SIGNBIT=1
+      AC_LIBOBJ([signbitf])
+      AC_LIBOBJ([signbitd])
+      AC_LIBOBJ([signbitl])
+      gl_FLOAT_SIGN_LOCATION
+      gl_DOUBLE_SIGN_LOCATION
+      gl_LONG_DOUBLE_SIGN_LOCATION
+      if test "$gl_cv_cc_float_signbit" = unknown; then
+        dnl Test whether copysignf() is declared.
+        AC_CHECK_DECLS([copysignf], , , [#include <math.h>])
+        if test "$ac_cv_have_decl_copysignf" = yes; then
+          dnl Test whether copysignf() can be used without libm.
+          AC_CACHE_CHECK([whether copysignf can be used without linking with libm],
+            [gl_cv_func_copysignf_no_libm],
+            [
+              AC_TRY_LINK([#include <math.h>
+                           float x, y;],
+                          [return copysignf (x, y) < 0;],
+                [gl_cv_func_copysignf_no_libm=yes],
+                [gl_cv_func_copysignf_no_libm=no])
+            ])
+          if test $gl_cv_func_copysignf_no_libm = yes; then
+            AC_DEFINE([HAVE_COPYSIGNF_IN_LIBC], [1],
+              [Define if the copysignf function is declared in <math.h> and available in libc.])
+          fi
+        fi
+      fi
+      if test "$gl_cv_cc_double_signbit" = unknown; then
+        dnl Test whether copysign() is declared.
+        AC_CHECK_DECLS([copysign], , , [#include <math.h>])
+        if test "$ac_cv_have_decl_copysign" = yes; then
+          dnl Test whether copysign() can be used without libm.
+          AC_CACHE_CHECK([whether copysign can be used without linking with libm],
+            [gl_cv_func_copysign_no_libm],
+            [
+              AC_TRY_LINK([#include <math.h>
+                           double x, y;],
+                          [return copysign (x, y) < 0;],
+                [gl_cv_func_copysign_no_libm=yes],
+                [gl_cv_func_copysign_no_libm=no])
+            ])
+          if test $gl_cv_func_copysign_no_libm = yes; then
+            AC_DEFINE([HAVE_COPYSIGN_IN_LIBC], [1],
+              [Define if the copysign function is declared in <math.h> and available in libc.])
+          fi
+        fi
+      fi
+      if test "$gl_cv_cc_long_double_signbit" = unknown; then
+        dnl Test whether copysignl() is declared.
+        AC_CHECK_DECLS([copysignl], , , [#include <math.h>])
+        if test "$ac_cv_have_decl_copysignl" = yes; then
+          dnl Test whether copysignl() can be used without libm.
+          AC_CACHE_CHECK([whether copysignl can be used without linking with libm],
+            [gl_cv_func_copysignl_no_libm],
+            [
+              AC_TRY_LINK([#include <math.h>
+                           long double x, y;],
+                          [return copysignl (x, y) < 0;],
+                [gl_cv_func_copysignl_no_libm=yes],
+                [gl_cv_func_copysignl_no_libm=no])
+            ])
+          if test $gl_cv_func_copysignl_no_libm = yes; then
+            AC_DEFINE([HAVE_COPYSIGNL_IN_LIBC], [1],
+              [Define if the copysignl function is declared in <math.h> and available in libc.])
+          fi
+        fi
+      fi
+    fi
+  fi
+])
+
+AC_DEFUN([gl_SIGNBIT_TEST_PROGRAM], [[
+/* Global variables.
+   Needed because GCC 4 constant-folds __builtin_signbitl (literal)
+   but cannot constant-fold            __builtin_signbitl (variable).  */
+float vf;
+double vd;
+long double vl;
+int main ()
+{
+/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
+   So we use -p0f and -p0d instead.  */
+float p0f = 0.0f;
+float m0f = -p0f;
+double p0d = 0.0;
+double m0d = -p0d;
+/* On HP-UX 10.20, negating 0.0L does not yield -0.0L.
+   So we use another constant expression instead.
+   But that expression does not work on other platforms, such as when
+   cross-compiling to PowerPC on MacOS X 10.5.  */
+long double p0l = 0.0L;
+#if defined __hpux || defined __sgi
+long double m0l = -LDBL_MIN * LDBL_MIN;
+#else
+long double m0l = -p0l;
+#endif
+  if (signbit (vf))
+    vf++;
+  {
+    float plus_inf = 1.0f / p0f;
+    float minus_inf = -1.0f / p0f;
+    if (!(!signbit (255.0f)
+          && signbit (-255.0f)
+          && !signbit (p0f)
+          && (memcmp (&m0f, &p0f, sizeof (float)) == 0 || signbit (m0f))
+          && !signbit (plus_inf)
+          && signbit (minus_inf)))
+      return 1;
+  }
+  if (signbit (vd))
+    vd++;
+  {
+    double plus_inf = 1.0 / p0d;
+    double minus_inf = -1.0 / p0d;
+    if (!(!signbit (255.0)
+          && signbit (-255.0)
+          && !signbit (p0d)
+          && (memcmp (&m0d, &p0d, sizeof (double)) == 0 || signbit (m0d))
+          && !signbit (plus_inf)
+          && signbit (minus_inf)))
+      return 1;
+  }
+  if (signbit (vl))
+    vl++;
+  {
+    long double plus_inf = 1.0L / p0l;
+    long double minus_inf = -1.0L / p0l;
+    if (!(!signbit (255.0L)
+          && signbit (-255.0L)
+          && !signbit (p0l)
+          && (memcmp (&m0l, &p0l, sizeof (long double)) == 0 || signbit (m0l))
+          && !signbit (plus_inf)
+          && signbit (minus_inf)))
+      return 1;
+  }
+  return 0;
+}
+]])
+
+AC_DEFUN([gl_FLOAT_SIGN_LOCATION],
+[
+  gl_FLOATTYPE_SIGN_LOCATION([float], [gl_cv_cc_float_signbit], [f], [FLT])
+])
+
+AC_DEFUN([gl_DOUBLE_SIGN_LOCATION],
+[
+  gl_FLOATTYPE_SIGN_LOCATION([double], [gl_cv_cc_double_signbit], [], [DBL])
+])
+
+AC_DEFUN([gl_LONG_DOUBLE_SIGN_LOCATION],
+[
+  gl_FLOATTYPE_SIGN_LOCATION([long double], [gl_cv_cc_long_double_signbit], [L], [LDBL])
+])
+
+AC_DEFUN([gl_FLOATTYPE_SIGN_LOCATION],
+[
+  AC_CACHE_CHECK([where to find the sign bit in a '$1'],
+    [$2],
+    [
+      AC_TRY_RUN([
+#include <stddef.h>
+#include <stdio.h>
+#define NWORDS \
+  ((sizeof ($1) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+typedef union { $1 value; unsigned int word[NWORDS]; }
+        memory_float;
+static memory_float plus = { 1.0$3 };
+static memory_float minus = { -1.0$3 };
+int main ()
+{
+  size_t j, k, i;
+  unsigned int m;
+  FILE *fp = fopen ("conftest.out", "w");
+  if (fp == NULL)
+    return 1;
+  /* Find the different bit.  */
+  k = 0; m = 0;
+  for (j = 0; j < NWORDS; j++)
+    {
+      unsigned int x = plus.word[j] ^ minus.word[j];
+      if ((x & (x - 1)) || (x && m))
+        {
+          /* More than one bit difference.  */
+          fprintf (fp, "unknown");
+          return 1;
+        }
+      if (x)
+        {
+          k = j;
+          m = x;
+        }
+    }
+  if (m == 0)
+    {
+      /* No difference.  */
+      fprintf (fp, "unknown");
+      return 1;
+    }
+  /* Now m = plus.word[k] ^ ~minus.word[k].  */
+  if (plus.word[k] & ~minus.word[k])
+    {
+      /* Oh? The sign bit is set in the positive and cleared in the negative
+         numbers?  */
+      fprintf (fp, "unknown");
+      return 1;
+    }
+  for (i = 0; ; i++)
+    if ((m >> i) & 1)
+      break;
+  fprintf (fp, "word %d bit %d", (int) k, (int) i);
+  return (fclose (fp) != 0);
+}
+        ],
+        [$2=`cat conftest.out`],
+        [$2="unknown"],
+        [
+          dnl When cross-compiling, we don't know. It depends on the
+          dnl ABI and compiler version. There are too many cases.
+          $2="unknown"
+        ])
+      rm -f conftest.out
+    ])
+  case "$]$2[" in
+    word*bit*)
+      word=`echo "$]$2[" | sed -e 's/word //' -e 's/ bit.*//'`
+      bit=`echo "$]$2[" | sed -e 's/word.*bit //'`
+      AC_DEFINE_UNQUOTED([$4][_SIGNBIT_WORD], [$word],
+        [Define as the word index where to find the sign of '$1'.])
+      AC_DEFINE_UNQUOTED([$4][_SIGNBIT_BIT], [$bit],
+        [Define as the bit index in the word where to find the sign of '$1'.])
+      ;;
+  esac
+])