* lib/math.in.h (log2l): New declaration.
* lib/log2l.c: New file.
* m4/log2l.m4: New file.
* m4/math_h.m4 (gl_MATH_H): Test whether log2l is declared.
(gl_MATH_H_DEFAULTS): Initialize GNULIB_LOG2L, HAVE_DECL_LOG2L,
REPLACE_LOG2L.
* modules/math (Makefile.am): Substitute GNULIB_LOG2L, HAVE_DECL_LOG2L,
REPLACE_LOG2L.
* modules/log2l: New file.
* tests/test-math-c++.cc: Check the declaration of log2l.
* doc/posix-functions/log2l.texi: Mention the new module and the IRIX
and OSF/1 problems.
+2012-03-11 Bruno Haible <bruno@clisp.org>
+
+ New module 'log2l'.
+ * lib/math.in.h (log2l): New declaration.
+ * lib/log2l.c: New file.
+ * m4/log2l.m4: New file.
+ * m4/math_h.m4 (gl_MATH_H): Test whether log2l is declared.
+ (gl_MATH_H_DEFAULTS): Initialize GNULIB_LOG2L, HAVE_DECL_LOG2L,
+ REPLACE_LOG2L.
+ * modules/math (Makefile.am): Substitute GNULIB_LOG2L, HAVE_DECL_LOG2L,
+ REPLACE_LOG2L.
+ * modules/log2l: New file.
+ * tests/test-math-c++.cc: Check the declaration of log2l.
+ * doc/posix-functions/log2l.texi: Mention the new module and the IRIX
+ and OSF/1 problems.
+
2012-03-11 Bruno Haible <bruno@clisp.org>
Tests for module 'log2f'.
POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/log2l.html}
-Gnulib module: ---
+Gnulib module: log2l
Portability problems fixed by Gnulib:
@itemize
+@item
+This function is missing on some platforms:
+FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, older IRIX 6.5, Solaris 9, Cygwin, MSVC 9, Interix 3.5, BeOS.
+@item
+This function is not declared on some platforms:
+IRIX 6.5.
+@item
+This function returns a wrong value for a minus zero argument on some platforms:
+OSF/1 5.1.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
-@item
-This function is missing on some platforms:
-FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, Cygwin, MSVC 9, Interix 3.5, BeOS.
@end itemize
--- /dev/null
+/* Base 2 logarithm.
+ Copyright (C) 2011-2012 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>
+
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+long double
+log2l (long double x)
+{
+ return log2 (x);
+}
+
+#else
+
+/* Best possible approximation of log(2) as a 'long double'. */
+#define LOG2 0.693147180559945309417232121458176568075L
+
+/* Best possible approximation of 1/log(2) as a 'long double'. */
+#define LOG2_INVERSE 1.44269504088896340735992468100189213743L
+
+/* sqrt(0.5). */
+#define SQRT_HALF 0.707106781186547524400844362104849039284L
+
+long double
+log2l (long double x)
+{
+ if (isnanl (x))
+ return x;
+
+ if (x <= 0.0L)
+ {
+ if (x == 0.0L)
+ /* Return -Infinity. */
+ return - HUGE_VALL;
+ else
+ {
+ /* Return NaN. */
+#if defined _MSC_VER || (defined __sgi && !defined __GNUC__)
+ static long double zero;
+ return zero / zero;
+#else
+ return 0.0L / 0.0L;
+#endif
+ }
+ }
+
+ /* Decompose x into
+ x = 2^e * y
+ where
+ e is an integer,
+ 1/2 < y < 2.
+ Then log2(x) = e + log2(y) = e + log(y)/log(2). */
+ {
+ int e;
+ long double y;
+
+ y = frexpl (x, &e);
+ if (y < SQRT_HALF)
+ {
+ y = 2.0L * y;
+ e = e - 1;
+ }
+
+ return (long double) e + logl (y) * LOG2_INVERSE;
+ }
+}
+
+#endif
# endif
#endif
+#if @GNULIB_LOG2L@
+# if @REPLACE_LOG2L@
+# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+# undef log2l
+# define log2l rpl_log2l
+# endif
+_GL_FUNCDECL_RPL (log2l, long double, (long double x));
+_GL_CXXALIAS_RPL (log2l, long double, (long double x));
+# else
+# if !@HAVE_DECL_LOG2L@
+_GL_FUNCDECL_SYS (log2l, long double, (long double x));
+# endif
+_GL_CXXALIAS_SYS (log2l, long double, (long double x));
+# endif
+_GL_CXXALIASWARN (log2l);
+#elif defined GNULIB_POSIXCHECK
+# undef log2l
+# if HAVE_RAW_DECL_LOG2L
+_GL_WARN_ON_USE (log2l, "log2l is unportable - "
+ "use gnulib module log2l for portability");
+# endif
+#endif
+
#if @GNULIB_MODFF@
# if @REPLACE_MODFF@
--- /dev/null
+# log2l.m4 serial 1
+dnl Copyright (C) 2010-2012 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_LOG2L],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+ AC_REQUIRE([gl_FUNC_LOG2])
+
+ dnl Persuade glibc <math.h> to declare log2l().
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+ dnl Test whether log2l() exists. Assume that log2l(), if it exists, is
+ dnl defined in the same library as log2().
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $LOG2_LIBM"
+ AC_CHECK_FUNCS([log2l])
+ LIBS="$save_LIBS"
+ if test $ac_cv_func_log2l = yes; then
+ LOG2L_LIBM="$LOG2_LIBM"
+ HAVE_LOG2L=1
+ dnl Also check whether it's declared.
+ dnl IRIX 6.5 has log2l() in libm but doesn't declare it in <math.h>.
+ AC_CHECK_DECL([log2l], , [HAVE_DECL_LOG2L=0], [[#include <math.h>]])
+
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $LOG2L_LIBM"
+ gl_FUNC_LOG2L_WORKS
+ LIBS="$save_LIBS"
+ case "$gl_cv_func_log2l_works" in
+ *yes) ;;
+ *) REPLACE_LOG2L=1 ;;
+ esac
+ else
+ HAVE_LOG2L=0
+ HAVE_DECL_LOG2L=0
+ fi
+ if test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; then
+ dnl Find libraries needed to link lib/log2l.c.
+ if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+ LOG2L_LIBM="$LOG2_LIBM"
+ else
+ AC_REQUIRE([gl_FUNC_ISNANL])
+ AC_REQUIRE([gl_FUNC_FREXPL])
+ AC_REQUIRE([gl_FUNC_LOGL])
+ LOG2L_LIBM=
+ dnl Append $ISNANL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
+ case " $LOG2L_LIBM " in
+ *" $ISNANL_LIBM "*) ;;
+ *) LOG2L_LIBM="$LOG2L_LIBM $ISNANL_LIBM" ;;
+ esac
+ dnl Append $FREXPL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
+ case " $LOG2L_LIBM " in
+ *" $FREXPL_LIBM "*) ;;
+ *) LOG2L_LIBM="$LOG2L_LIBM $FREXPL_LIBM" ;;
+ esac
+ dnl Append $LOGL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
+ case " $LOG2L_LIBM " in
+ *" $LOGL_LIBM "*) ;;
+ *) LOG2L_LIBM="$LOG2L_LIBM $LOGL_LIBM" ;;
+ esac
+ fi
+ fi
+ AC_SUBST([LOG2L_LIBM])
+])
+
+dnl Test whether log2l() works.
+dnl On OSF/1 5.1, log2l(-0.0) is NaN.
+AC_DEFUN([gl_FUNC_LOG2L_WORKS],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether log2l works], [gl_cv_func_log2l_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <math.h>
+#ifndef log2l /* for AIX */
+extern
+#ifdef __cplusplus
+"C"
+#endif
+long double log2l (long double);
+#endif
+volatile long double x;
+volatile long double y;
+int main ()
+{
+ /* This test fails on OSF/1 5.1. */
+ x = -0.0L;
+ y = log2l (x);
+ if (!(y + y == y))
+ return 1;
+ return 0;
+}
+]])],
+ [gl_cv_func_log2l_works=yes],
+ [gl_cv_func_log2l_works=no],
+ [case "$host_os" in
+ osf*) gl_cv_func_log2l_works="guessing no";;
+ *) gl_cv_func_log2l_works="guessing yes";;
+ esac
+ ])
+ ])
+])
-# math_h.m4 serial 102
+# math_h.m4 serial 103
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,
fabsf fabsl floorf floorl fma fmaf fmal
fmod fmodf fmodl frexpf frexpl hypotf hypotl
ldexpf ldexpl
- logb log logf logl log10f log10l log1p log1pf log1pl log2 log2f
+ logb log logf logl log10f log10l log1p log1pf log1pl log2 log2f log2l
modf modff modfl powf
remainder remainderf remainderl
rint rintf rintl round roundf roundl sinf sinl sinhf sqrtf sqrtl
GNULIB_LOG1PL=0; AC_SUBST([GNULIB_LOG1PL])
GNULIB_LOG2=0; AC_SUBST([GNULIB_LOG2])
GNULIB_LOG2F=0; AC_SUBST([GNULIB_LOG2F])
+ GNULIB_LOG2L=0; AC_SUBST([GNULIB_LOG2L])
GNULIB_MODF=0; AC_SUBST([GNULIB_MODF])
GNULIB_MODFF=0; AC_SUBST([GNULIB_MODFF])
GNULIB_MODFL=0; AC_SUBST([GNULIB_MODFL])
HAVE_DECL_LOG10L=1; AC_SUBST([HAVE_DECL_LOG10L])
HAVE_DECL_LOG2=1; AC_SUBST([HAVE_DECL_LOG2])
HAVE_DECL_LOG2F=1; AC_SUBST([HAVE_DECL_LOG2F])
+ HAVE_DECL_LOG2L=1; AC_SUBST([HAVE_DECL_LOG2L])
HAVE_DECL_REMAINDER=1; AC_SUBST([HAVE_DECL_REMAINDER])
HAVE_DECL_REMAINDERL=1; AC_SUBST([HAVE_DECL_REMAINDERL])
HAVE_DECL_RINTF=1; AC_SUBST([HAVE_DECL_RINTF])
REPLACE_LOG1PL=0; AC_SUBST([REPLACE_LOG1PL])
REPLACE_LOG2=0; AC_SUBST([REPLACE_LOG2])
REPLACE_LOG2F=0; AC_SUBST([REPLACE_LOG2F])
+ REPLACE_LOG2L=0; AC_SUBST([REPLACE_LOG2L])
REPLACE_MODF=0; AC_SUBST([REPLACE_MODF])
REPLACE_MODFF=0; AC_SUBST([REPLACE_MODFF])
REPLACE_MODFL=0; AC_SUBST([REPLACE_MODFL])
--- /dev/null
+Description:
+log2() function: base 2 logarithm.
+
+Files:
+lib/log2l.c
+m4/log2l.m4
+
+Depends-on:
+math
+extensions
+log2 [{ test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
+isnanl [{ test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
+frexpl [{ test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
+logl [{ test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
+
+configure.ac:
+gl_FUNC_LOG2L
+if test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; then
+ AC_LIBOBJ([log2l])
+fi
+gl_MATH_MODULE_INDICATOR([log2l])
+
+Makefile.am:
+
+Include:
+<math.h>
+
+Link:
+$(LOG2L_LIBM)
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
-e 's/@''GNULIB_LOG1PL''@/$(GNULIB_LOG1PL)/g' \
-e 's/@''GNULIB_LOG2''@/$(GNULIB_LOG2)/g' \
-e 's/@''GNULIB_LOG2F''@/$(GNULIB_LOG2F)/g' \
+ -e 's/@''GNULIB_LOG2L''@/$(GNULIB_LOG2L)/g' \
-e 's/@''GNULIB_MODF''@/$(GNULIB_MODF)/g' \
-e 's/@''GNULIB_MODFF''@/$(GNULIB_MODFF)/g' \
-e 's/@''GNULIB_MODFL''@/$(GNULIB_MODFL)/g' \
-e 's|@''HAVE_DECL_LOG10L''@|$(HAVE_DECL_LOG10L)|g' \
-e 's|@''HAVE_DECL_LOG2''@|$(HAVE_DECL_LOG2)|g' \
-e 's|@''HAVE_DECL_LOG2F''@|$(HAVE_DECL_LOG2F)|g' \
+ -e 's|@''HAVE_DECL_LOG2L''@|$(HAVE_DECL_LOG2L)|g' \
-e 's|@''HAVE_DECL_REMAINDER''@|$(HAVE_DECL_REMAINDER)|g' \
-e 's|@''HAVE_DECL_REMAINDERL''@|$(HAVE_DECL_REMAINDERL)|g' \
-e 's|@''HAVE_DECL_RINTF''@|$(HAVE_DECL_RINTF)|g' \
-e 's|@''REPLACE_LOG1PL''@|$(REPLACE_LOG1PL)|g' \
-e 's|@''REPLACE_LOG2''@|$(REPLACE_LOG2)|g' \
-e 's|@''REPLACE_LOG2F''@|$(REPLACE_LOG2F)|g' \
+ -e 's|@''REPLACE_LOG2L''@|$(REPLACE_LOG2L)|g' \
-e 's|@''REPLACE_MODF''@|$(REPLACE_MODF)|g' \
-e 's|@''REPLACE_MODFF''@|$(REPLACE_MODFF)|g' \
-e 's|@''REPLACE_MODFL''@|$(REPLACE_MODFL)|g' \
#if GNULIB_TEST_LOG2
SIGNATURE_CHECK (GNULIB_NAMESPACE::log2, double, (double));
#endif
+#if GNULIB_TEST_LOG2L
+SIGNATURE_CHECK (GNULIB_NAMESPACE::log2l, long double, (long double));
+#endif
#if GNULIB_TEST_MODFF
SIGNATURE_CHECK (GNULIB_NAMESPACE::modff, float, (float, float *));