changeset 8650:a555b16abc8a

New module 'isnanf-nolibm'.
author Bruno Haible <bruno@clisp.org>
date Fri, 06 Apr 2007 20:19:19 +0000
parents ca75eb69fcf4
children acd997e2cee5
files ChangeLog lib/isnan.c lib/isnanf.c lib/isnanf.h m4/isnanf.m4 modules/isnanf-nolibm
diffstat 6 files changed, 224 insertions(+), 79 deletions(-) [+]
line wrap: on
line diff
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2007-04-06  Bruno Haible  <bruno@clisp.org>
+
+	* modules/isnanf-nolibm: New file.
+	* lib/isnanf.h: New file.
+	* lib/isnanf.c: New file.
+	* lib/isnan.c: Consider the USE_FLOAT macro.
+	* m4/isnanf.m4: New file.
+
 2007-04-06  Bruno Haible  <bruno@clisp.org>
 
 	* modules/gettext-h (configure.ac): AC_SUBST LIBINTL and LTLIBINTL.
@@ -29491,81 +29499,4 @@
 
 	* m4/isc-posix.m4: New file.
 
-1998-05-10  Jim Meyering  <meyering@ascend.com>
-
-	* m4/jm-mktime.m4: Use AM_FUNC_MKTIME, now that it's up to date.
-
-1998-05-09  Jim Meyering  <meyering@ascend.com>
-
-	* m4/Makefile.am (EXTRA_DIST): Add ssize_t.m4.
-	(EXTRA_DIST): Remove mktime.m4, now that the new version is included
-	with automake.
-
-	* m4/ssize_t.m4: New file.
-	* m4/mktime.m4: Remove file -- the new automake has this now.
-
-1998-04-26  Jim Meyering  <meyering@ascend.com>
-
-	* m4/assert.m4: New file.
-	* m4/Makefile.am (EXTRA_DIST): Add assert.m4.
-
-1998-04-05  Jim Meyering  <meyering@ascend.com>
-
-	* m4/prereq.m4 (jm_PREREQ_REGEX): New macro.
-	(jm_PREREQ): Use it here.
-
-1998-03-23  Jim Meyering  <meyering@eng.ascend.com>
-
-	* m4/inttypes_h.m4: Kludges so I don't have to add HAVE_INTTYPES_H
-	in acconfig.h.
-
-1998-03-15  Jim Meyering  <meyering@eng.ascend.com>
-
-	* m4/prereq.m4: New file.
-	* m4/error.m4: New file.
-	* m4/Makefile.am (EXTRA_DIST): Add error.m4 and prereq.m4.
-
-1998-02-07  Jim Meyering  <meyering@eng.ascend.com>
-
-	* m4/getline.m4: Don't set am_cv_func_working_getline before the
-	cache-check for the same variable -- that defeated the purpose of
-	the test; the test program was never run.  This was a problem only
-	on systems with losing getline functions -- HP-UX 10.20 is one.
-	Reported by Bjorn Helgaas.
-
-1998-02-06  Jim Meyering  <meyering@eng.ascend.com>
-
-	* m4/Makefile.am (EXTRA_DIST): Add perl.m4.
-
-1998-01-10  Jim Meyering  <meyering@na-net.ornl.gov>
-
-	* m4/Makefile.am (EXTRA_DIST): Add const.m4.
-
-	* m4/const.m4: New file.  Use an initializer in this declaration
-	typedef int charset[2]; const charset x;
-	Reported by Bob Glickstein.
-
-1997-12-21  Jim Meyering  <meyering@na-net.ornl.gov>
-
-	* m4/chown.m4: Fix reversed types on -1 args to chown.
-	From Kaveh Ghazi.
-
-1997-12-14  Jim Meyering  <meyering@na-net.ornl.gov>
-
-	* m4/check-decl.m4: s/DECLARATION_/DECL_/g.
-	Add lseek and memchr.
-
-	* m4/decl.m4: s/HAVE_DECLARATION_/HAVE_DECL_/g.
-	T.E.Dickey <dickey@clark.net> said that some older preprocessors
-	have a 20-character limit on names.
-
-1997-11-30  Jim Meyering  <meyering@na-net.ornl.gov>
-
-	* m4/inttypes_h.m4: New file.
-	* m4/uintmax_t.m4: New file.
-	* m4/Makefile.am (EXTRA_DIST): Add inttypes_h.m4 and uintmax_t.m4.
-
-Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
-  Free Software Foundation, Inc.
-Copying and distribution of this file, with or without modification,
-are permitted provided the copyright notice and this notice are preserved.
+1998-05-10  Jim Meyering  <meyering@ascend.com>
\ No newline at end of file
--- a/lib/isnan.c
+++ b/lib/isnan.c
@@ -36,7 +36,7 @@
 # endif
 # define SIZE SIZEOF_LDBL
 # define L_(literal) literal##L
-#else
+#elif ! defined USE_FLOAT
 # define FUNC rpl_isnan
 # define DOUBLE double
 # define MAX_EXP DBL_MAX_EXP
@@ -48,6 +48,18 @@
 # endif
 # define SIZE SIZEOF_DBL
 # define L_(literal) literal
+#else /* defined USE_FLOAT */
+# define FUNC rpl_isnanf
+# define DOUBLE float
+# define MAX_EXP FLT_MAX_EXP
+# define MIN_EXP FLT_MIN_EXP
+# if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
+#  define KNOWN_EXPBIT0_LOCATION
+#  define EXPBIT0_WORD FLT_EXPBIT0_WORD
+#  define EXPBIT0_BIT FLT_EXPBIT0_BIT
+# endif
+# define SIZE SIZEOF_FLT
+# define L_(literal) literal##f
 #endif
 
 #define EXP_MASK ((MAX_EXP - MIN_EXP) | 7)
new file mode 100644
--- /dev/null
+++ b/lib/isnanf.c
@@ -0,0 +1,21 @@
+/* Test for NaN that does not need libm.
+   Copyright (C) 2007 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 2, 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, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2007.  */
+
+#define USE_FLOAT
+#include "isnan.c"
new file mode 100644
--- /dev/null
+++ b/lib/isnanf.h
@@ -0,0 +1,30 @@
+/* Test for NaN that does not need libm.
+   Copyright (C) 2007 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 2, 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, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#if HAVE_ISNANF_IN_LIBC
+/* Get declaration of isnan macro or (older) isnanf function.  */
+# include <math.h>
+# ifdef isnan
+#  undef isnanf
+#  define isnanf(x) isnan ((float)(x))
+# endif
+#else
+/* Test whether X is a NaN.  */
+# undef isnanf
+# define isnanf rpl_isnanf
+extern int isnanf (float x);
+#endif
new file mode 100644
--- /dev/null
+++ b/m4/isnanf.m4
@@ -0,0 +1,124 @@
+# isnanf.m4 serial 1
+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 isnanf() without linking with libm.
+
+AC_DEFUN([gl_FUNC_ISNANF_NO_LIBM],
+[
+  gl_HAVE_ISNANF_NO_LIBM
+  if test $gl_cv_func_isnanf_no_libm = yes; then
+    AC_DEFINE([HAVE_ISNANF_IN_LIBC], 1,
+      [Define if the isnan(float) function is available in libc.])
+  else
+    AC_LIBOBJ([isnanf])
+    gl_FLOAT_EXPONENT_LOCATION
+  fi
+])
+
+dnl Test whether isnanf() can be used without libm.
+AC_DEFUN([gl_HAVE_ISNANF_NO_LIBM],
+[
+  AC_CACHE_CHECK([whether isnan(float) can be used without linking with libm],
+    [gl_cv_func_isnanf_no_libm],
+    [
+      AC_TRY_LINK([#include <math.h>
+                   #ifdef isnan
+                   # undef isnanf
+                   # define isnanf(x) isnan ((float)(x))
+                   #endif
+                   float x;],
+                  [return isnanf (x);],
+        [gl_cv_func_isnanf_no_libm=yes],
+        [gl_cv_func_isnanf_no_libm=no])
+    ])
+])
+
+AC_DEFUN([gl_FLOAT_EXPONENT_LOCATION],
+[
+  AC_CACHE_CHECK([where to find the exponent in a 'float'],
+    [gl_cv_cc_float_expbit0],
+    [
+      AC_TRY_RUN([
+#include <float.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#define NWORDS \
+  ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+typedef union { float value; unsigned int word[NWORDS]; } memory_float;
+static unsigned int ored_words[NWORDS];
+static unsigned int anded_words[NWORDS];
+static void add_to_ored_words (float x)
+{
+  memory_float m;
+  size_t i;
+  /* Clear it first, in case
+     sizeof (float) < sizeof (memory_float).  */
+  memset (&m, 0, sizeof (memory_float));
+  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 (0.25f);
+  add_to_ored_words (0.5f);
+  add_to_ored_words (1.0f);
+  add_to_ored_words (2.0f);
+  add_to_ored_words (4.0f);
+  /* 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_float_expbit0=`cat conftest.out`],
+        [gl_cv_cc_float_expbit0="unknown"],
+        [gl_cv_cc_double_expbit0="word 0 bit 23"])
+      rm -f conftest.out
+    ])
+  case "$gl_cv_cc_float_expbit0" in
+    word*bit*)
+      word=`echo "$gl_cv_cc_float_expbit0" | sed -e 's/word //' -e 's/ bit.*//'`
+      bit=`echo "$gl_cv_cc_float_expbit0" | sed -e 's/word.*bit //'`
+      AC_DEFINE_UNQUOTED([FLT_EXPBIT0_WORD], [$word],
+        [Define as the word index where to find the exponent of 'float'.])
+      AC_DEFINE_UNQUOTED([FLT_EXPBIT0_BIT], [$bit],
+        [Define as the bit index in the word where to find bit 0 of the exponent of 'float'.])
+      ;;
+  esac
+])
new file mode 100644
--- /dev/null
+++ b/modules/isnanf-nolibm
@@ -0,0 +1,27 @@
+Description:
+isnanf() function: test for NaN, without requiring libm.
+
+Files:
+lib/isnanf.h
+lib/isnanf.c
+lib/isnan.c
+lib/float+.h
+m4/isnanf.m4
+
+Depends-on:
+fpieee
+
+configure.ac:
+gl_FUNC_ISNANF_NO_LIBM
+
+Makefile.am:
+
+Include:
+#include "isnanf.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+