+2011-10-10 Bruno Haible <bruno@clisp.org>
+
+ expl: Simplify for platforms where 'long double' == 'double'.
+ * lib/expl.c (expl) [HAVE_SAME_LONG_DOUBLE_AS_DOUBLE]: New alternative
+ implementation.
+ * m4/expl.m4 (gl_FUNC_EXPL): Require gl_LONG_DOUBLE_VS_DOUBLE.
+ Determine EXPL_LIBM according to HAVE_SAME_LONG_DOUBLE_AS_DOUBLE.
+ * modules/expl (Depends-on): Add exp. Update conditions.
+
2011-10-10 Bruno Haible <bruno@clisp.org>
sqrtl: Simplify for platforms where 'long double' == 'double'.
/* Specification. */
#include <math.h>
-#include <float.h>
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+long double
+expl (long double x)
+{
+ return exp (x);
+}
+
+#else
+
+# include <float.h>
static const long double C[] = {
/* Chebyshev polynom coeficients for (exp(x)-1)/x */
-#define P1 C[0]
-#define P2 C[1]
-#define P3 C[2]
-#define P4 C[3]
-#define P5 C[4]
-#define P6 C[5]
+# define P1 C[0]
+# define P2 C[1]
+# define P3 C[2]
+# define P4 C[3]
+# define P5 C[4]
+# define P6 C[5]
0.5L,
1.66666666666666666666666666666666683E-01L,
4.16666666666666666666654902320001674E-02L,
1.98412698413981650382436541785404286E-04L,
/* Smallest integer x for which e^x overflows. */
-#define himark C[6]
+# define himark C[6]
11356.523406294143949491931077970765L,
/* Largest integer x for which e^x underflows. */
-#define lomark C[7]
+# define lomark C[7]
-11433.4627433362978788372438434526231L,
/* very small number */
-#define TINY C[8]
+# define TINY C[8]
1.0e-4900L,
/* 2^16383 */
-#define TWO16383 C[9]
+# define TWO16383 C[9]
5.94865747678615882542879663314003565E+4931L};
long double
return TWO16383*x;
}
+#endif
+
#if 0
int
main (void)
-# expl.m4 serial 4
+# expl.m4 serial 5
dnl Copyright (C) 2010-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
AC_DEFUN([gl_FUNC_EXPL],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+
dnl Persuade glibc <math.h> to declare expl().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
HAVE_DECL_EXPL=0
HAVE_EXPL=0
dnl Find libraries needed to link lib/expl.c.
- AC_REQUIRE([gl_FUNC_FLOORL])
- EXPL_LIBM="$FLOORL_LIBM"
+ if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+ AC_REQUIRE([gl_FUNC_EXP])
+ EXPL_LIBM="$EXP_LIBM"
+ else
+ AC_REQUIRE([gl_FUNC_FLOORL])
+ EXPL_LIBM="$FLOORL_LIBM"
+ fi
fi
AC_SUBST([EXPL_LIBM])
])
Depends-on:
math
extensions
-float [test $HAVE_EXPL = 0]
-floorl [test $HAVE_EXPL = 0]
+exp [test $HAVE_EXPL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
+float [test $HAVE_EXPL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
+floorl [test $HAVE_EXPL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
configure.ac:
gl_FUNC_EXPL