changeset 16753:0f9a8ebc12c1

New module 'logbf'. * lib/math.in.h (logbf): New declaration. * lib/logbf.c: New file. * m4/logbf.m4: New file. * m4/math_h.m4 (gl_MATH_H): Test whether logbf is declared. (gl_MATH_H_DEFAULTS): Initialize GNULIB_LOGBF, HAVE_LOGBF, REPLACE_LOGBF. * modules/math (Makefile.am): Substitute GNULIB_LOGBF, HAVE_LOGBF, REPLACE_LOGBF. * modules/logbf: New file. * tests/test-math-c++.cc: Check the declaration of logbf. * doc/posix-functions/logbf.texi: Mention the new module.
author Bruno Haible <bruno@clisp.org>
date Tue, 03 Apr 2012 04:44:59 +0200
parents 27c536025f33
children bd1b9733233d
files ChangeLog doc/posix-functions/logbf.texi lib/logbf.c lib/math.in.h m4/logbf.m4 m4/math_h.m4 modules/logbf modules/math tests/test-math-c++.cc
diffstat 9 files changed, 196 insertions(+), 6 deletions(-) [+]
line wrap: on
line diff
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,18 @@
+2012-04-02  Bruno Haible  <bruno@clisp.org>
+
+	New module 'logbf'.
+	* lib/math.in.h (logbf): New declaration.
+	* lib/logbf.c: New file.
+	* m4/logbf.m4: New file.
+	* m4/math_h.m4 (gl_MATH_H): Test whether logbf is declared.
+	(gl_MATH_H_DEFAULTS): Initialize GNULIB_LOGBF, HAVE_LOGBF,
+	REPLACE_LOGBF.
+	* modules/math (Makefile.am): Substitute GNULIB_LOGBF, HAVE_LOGBF,
+	REPLACE_LOGBF.
+	* modules/logbf: New file.
+	* tests/test-math-c++.cc: Check the declaration of logbf.
+	* doc/posix-functions/logbf.texi: Mention the new module.
+
 2012-04-02  Bruno Haible  <bruno@clisp.org>
 
 	logb tests: More tests.
--- a/doc/posix-functions/logbf.texi
+++ b/doc/posix-functions/logbf.texi
@@ -4,15 +4,18 @@
 
 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/logbf.html}
 
-Gnulib module: ---
+Gnulib module: logbf
 
 Portability problems fixed by Gnulib:
 @itemize
+@item
+This function is missing on some platforms:
+Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, MSVC 9.
+@item
+This function produces wrong results for subnormal numbers on some platforms:
+glibc 2.11/ppc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 11 2011-11.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
-@item
-This function is missing on some platforms:
-Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, MSVC 9.
 @end itemize
new file mode 100644
--- /dev/null
+++ b/lib/logbf.c
@@ -0,0 +1,23 @@
+/* Floating-point exponent.
+   Copyright (C) 2012 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 <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <math.h>
+
+#define USE_FLOAT
+#include "logb.c"
--- a/lib/math.in.h
+++ b/lib/math.in.h
@@ -1388,6 +1388,29 @@
 #endif
 
 
+#if @GNULIB_LOGBF@
+# if @REPLACE_LOGBF@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef logbf
+#   define logbf rpl_logbf
+#  endif
+_GL_FUNCDECL_RPL (logbf, float, (float x));
+_GL_CXXALIAS_RPL (logbf, float, (float x));
+# else
+#  if !@HAVE_LOGBF@
+_GL_FUNCDECL_SYS (logbf, float, (float x));
+#  endif
+_GL_CXXALIAS_SYS (logbf, float, (float x));
+# endif
+_GL_CXXALIASWARN (logbf);
+#elif defined GNULIB_POSIXCHECK
+# undef logbf
+# if HAVE_RAW_DECL_LOGBF
+_GL_WARN_ON_USE (logbf, "logbf is unportable - "
+                 "use gnulib module logbf for portability");
+# endif
+#endif
+
 #if @GNULIB_LOGB@
 # if @REPLACE_LOGB@
 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
new file mode 100644
--- /dev/null
+++ b/m4/logbf.m4
@@ -0,0 +1,81 @@
+# logbf.m4 serial 1
+dnl Copyright (C) 2012 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_FUNC_LOGBF],
+[
+  AC_REQUIRE([gl_MATH_H_DEFAULTS])
+
+  dnl Persuade glibc <math.h> to declare logbf().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+  dnl Determine LOGBF_LIBM.
+  gl_MATHFUNC([logbf], [float], [(float)])
+  if test $gl_cv_func_logbf_no_libm = yes \
+     || test $gl_cv_func_logbf_in_libm = yes; then
+    save_LIBS="$LIBS"
+    LIBS="$LIBS $LOGBF_LIBM"
+    gl_FUNC_LOGBF_WORKS
+    LIBS="$save_LIBS"
+    case "$gl_cv_func_logbf_works" in
+      *yes) ;;
+      *) REPLACE_LOGBF=1 ;;
+    esac
+  else
+    HAVE_LOGBF=0
+  fi
+  if test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1; then
+    dnl Find libraries needed to link lib/logbf.c.
+    AC_REQUIRE([gl_FUNC_FREXPF])
+    AC_REQUIRE([gl_FUNC_ISNANF])
+    LOGBF_LIBM=
+    dnl Append $FREXPF_LIBM to LOGBF_LIBM, avoiding gratuitous duplicates.
+    case " $LOGBF_LIBM " in
+      *" $FREXPF_LIBM "*) ;;
+      *) LOGBF_LIBM="$LOGBF_LIBM $FREXPF_LIBM" ;;
+    esac
+    dnl Append $ISNANF_LIBM to LOGBF_LIBM, avoiding gratuitous duplicates.
+    case " $LOGBF_LIBM " in
+      *" $ISNANF_LIBM "*) ;;
+      *) LOGBF_LIBM="$LOGBF_LIBM $ISNANF_LIBM" ;;
+    esac
+  fi
+  AC_SUBST([LOGBF_LIBM])
+])
+
+dnl Test whether logbf() works.
+dnl On glibc 2.11/ppc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 10/SPARC,
+dnl the return value for subnormal (denormalized) arguments is too large.
+AC_DEFUN([gl_FUNC_LOGBF_WORKS],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CACHE_CHECK([whether logbf works], [gl_cv_func_logbf_works],
+    [
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+#include <float.h>
+#include <math.h>
+volatile float x;
+int main ()
+{
+  int i;
+  for (i = 1, x = 1.0f; i >= FLT_MIN_EXP; i--, x *= 0.5f)
+    ;
+  /* Here i = FLT_MIN_EXP - 1. Either x = 2^(i-1) is subnormal or x = 0.0.  */
+  if (x > 0.0f && !(logbf (x) == (float)(i - 1)))
+    return 1;
+  return 0;
+}
+]])],
+        [gl_cv_func_logbf_works=yes],
+        [gl_cv_func_logbf_works=no],
+        [case "$host_os" in
+           *gnu* | solaris*) gl_cv_func_logbf_works="guessing no";;
+           *)                gl_cv_func_logbf_works="guessing yes";;
+         esac
+        ])
+    ])
+])
--- a/m4/math_h.m4
+++ b/m4/math_h.m4
@@ -1,4 +1,4 @@
-# math_h.m4 serial 108
+# math_h.m4 serial 109
 dnl Copyright (C) 2007-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -46,7 +46,7 @@
      fmod fmodf fmodl frexpf frexpl hypotf hypotl
      ldexpf ldexpl
      log logf logl log10 log10f log10l log1p log1pf log1pl log2 log2f log2l
-     logb
+     logb logbf
      modf modff modfl powf
      remainder remainderf remainderl
      rint rintf rintl round roundf roundl sinf sinl sinhf sqrtf sqrtl
@@ -129,6 +129,7 @@
   GNULIB_LOG2F=0;      AC_SUBST([GNULIB_LOG2F])
   GNULIB_LOG2L=0;      AC_SUBST([GNULIB_LOG2L])
   GNULIB_LOGB=0;       AC_SUBST([GNULIB_LOGB])
+  GNULIB_LOGBF=0;      AC_SUBST([GNULIB_LOGBF])
   GNULIB_MODF=0;       AC_SUBST([GNULIB_MODF])
   GNULIB_MODFF=0;      AC_SUBST([GNULIB_MODFF])
   GNULIB_MODFL=0;      AC_SUBST([GNULIB_MODFL])
@@ -195,6 +196,7 @@
   HAVE_LOG1P=1;                AC_SUBST([HAVE_LOG1P])
   HAVE_LOG1PF=1;               AC_SUBST([HAVE_LOG1PF])
   HAVE_LOG1PL=1;               AC_SUBST([HAVE_LOG1PL])
+  HAVE_LOGBF=1;                AC_SUBST([HAVE_LOGBF])
   HAVE_MODFF=1;                AC_SUBST([HAVE_MODFF])
   HAVE_MODFL=1;                AC_SUBST([HAVE_MODFL])
   HAVE_POWF=1;                 AC_SUBST([HAVE_POWF])
@@ -289,6 +291,7 @@
   REPLACE_LOG2F=0;             AC_SUBST([REPLACE_LOG2F])
   REPLACE_LOG2L=0;             AC_SUBST([REPLACE_LOG2L])
   REPLACE_LOGB=0;              AC_SUBST([REPLACE_LOGB])
+  REPLACE_LOGBF=0;             AC_SUBST([REPLACE_LOGBF])
   REPLACE_MODF=0;              AC_SUBST([REPLACE_MODF])
   REPLACE_MODFF=0;             AC_SUBST([REPLACE_MODFF])
   REPLACE_MODFL=0;             AC_SUBST([REPLACE_MODFL])
new file mode 100644
--- /dev/null
+++ b/modules/logbf
@@ -0,0 +1,36 @@
+Description:
+logbf() function: get exponent.
+
+Files:
+lib/logbf.c
+lib/logb.c
+m4/logbf.m4
+m4/mathfunc.m4
+
+Depends-on:
+math
+extensions
+isfinite        [test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1]
+frexpf          [test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1]
+isnanf          [test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1]
+
+configure.ac:
+gl_FUNC_LOGBF
+if test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1; then
+  AC_LIBOBJ([logbf])
+fi
+gl_MATH_MODULE_INDICATOR([logbf])
+
+Makefile.am:
+
+Include:
+<math.h>
+
+Link:
+$(LOGBF_LIBM)
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
--- a/modules/math
+++ b/modules/math
@@ -93,6 +93,7 @@
 	      -e 's/@''GNULIB_LOG2F''@/$(GNULIB_LOG2F)/g' \
 	      -e 's/@''GNULIB_LOG2L''@/$(GNULIB_LOG2L)/g' \
 	      -e 's/@''GNULIB_LOGB''@/$(GNULIB_LOGB)/g' \
+	      -e 's/@''GNULIB_LOGBF''@/$(GNULIB_LOGBF)/g' \
 	      -e 's/@''GNULIB_MODF''@/$(GNULIB_MODF)/g' \
 	      -e 's/@''GNULIB_MODFF''@/$(GNULIB_MODFF)/g' \
 	      -e 's/@''GNULIB_MODFL''@/$(GNULIB_MODFL)/g' \
@@ -159,6 +160,7 @@
 	      -e 's|@''HAVE_LOG1P''@|$(HAVE_LOG1P)|g' \
 	      -e 's|@''HAVE_LOG1PF''@|$(HAVE_LOG1PF)|g' \
 	      -e 's|@''HAVE_LOG1PL''@|$(HAVE_LOG1PL)|g' \
+	      -e 's|@''HAVE_LOGBF''@|$(HAVE_LOGBF)|g' \
 	      -e 's|@''HAVE_MODFF''@|$(HAVE_MODFF)|g' \
 	      -e 's|@''HAVE_MODFL''@|$(HAVE_MODFL)|g' \
 	      -e 's|@''HAVE_POWF''@|$(HAVE_POWF)|g' \
@@ -255,6 +257,7 @@
 	      -e 's|@''REPLACE_LOG2F''@|$(REPLACE_LOG2F)|g' \
 	      -e 's|@''REPLACE_LOG2L''@|$(REPLACE_LOG2L)|g' \
 	      -e 's|@''REPLACE_LOGB''@|$(REPLACE_LOGB)|g' \
+	      -e 's|@''REPLACE_LOGBF''@|$(REPLACE_LOGBF)|g' \
 	      -e 's|@''REPLACE_MODF''@|$(REPLACE_MODF)|g' \
 	      -e 's|@''REPLACE_MODFF''@|$(REPLACE_MODFF)|g' \
 	      -e 's|@''REPLACE_MODFL''@|$(REPLACE_MODFL)|g' \
--- a/tests/test-math-c++.cc
+++ b/tests/test-math-c++.cc
@@ -251,6 +251,9 @@
 SIGNATURE_CHECK (GNULIB_NAMESPACE::log2l, long double, (long double));
 #endif
 
+#if GNULIB_TEST_LOGBF
+SIGNATURE_CHECK (GNULIB_NAMESPACE::logbf, float, (float));
+#endif
 #if GNULIB_TEST_LOGB
 SIGNATURE_CHECK (GNULIB_NAMESPACE::logb, double, (double));
 #endif