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Diffstat (limited to 'gnulib-m4/isnanl.m4')
-rw-r--r-- | gnulib-m4/isnanl.m4 | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/gnulib-m4/isnanl.m4 b/gnulib-m4/isnanl.m4 new file mode 100644 index 00000000..e3029f5c --- /dev/null +++ b/gnulib-m4/isnanl.m4 @@ -0,0 +1,245 @@ +# isnanl.m4 serial 12 +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_FUNC_ISNANL], +[ + AC_REQUIRE([gl_MATH_H_DEFAULTS]) + ISNANL_LIBM= + gl_HAVE_ISNANL_NO_LIBM + if test $gl_cv_func_isnanl_no_libm = no; then + gl_HAVE_ISNANL_IN_LIBM + if test $gl_cv_func_isnanl_in_libm = yes; then + ISNANL_LIBM=-lm + fi + fi + if test $gl_cv_func_isnanl_no_libm = yes \ + || test $gl_cv_func_isnanl_in_libm = yes; then + save_LIBS="$LIBS" + LIBS="$LIBS $ISNANL_LIBM" + gl_FUNC_ISNANL_WORKS + LIBS="$save_LIBS" + case "$gl_cv_func_isnanl_works" in + *yes) gl_func_isnanl=yes ;; + *) gl_func_isnanl=no; ISNANL_LIBM= ;; + esac + else + gl_func_isnanl=no + fi + if test $gl_func_isnanl != yes; then + HAVE_ISNANL=0 + gl_BUILD_ISNANL + fi + AC_SUBST([ISNANL_LIBM]) +]) + +AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM], +[ + gl_HAVE_ISNANL_NO_LIBM + gl_func_isnanl_no_libm=$gl_cv_func_isnanl_no_libm + if test $gl_func_isnanl_no_libm = yes; then + gl_FUNC_ISNANL_WORKS + case "$gl_cv_func_isnanl_works" in + *yes) ;; + *) gl_func_isnanl_no_libm=no ;; + esac + fi + if test $gl_func_isnanl_no_libm = yes; then + AC_DEFINE([HAVE_ISNANL_IN_LIBC], [1], + [Define if the isnan(long double) function is available in libc.]) + else + gl_BUILD_ISNANL + fi +]) + +dnl Pull in replacement isnanl definition. It does not need -lm. +AC_DEFUN([gl_BUILD_ISNANL], +[ + AC_LIBOBJ([isnanl]) + gl_LONG_DOUBLE_EXPONENT_LOCATION +]) + +dnl Test whether isnanl() can be used without libm. +AC_DEFUN([gl_HAVE_ISNANL_NO_LIBM], +[ + AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm], + [gl_cv_func_isnanl_no_libm], + [ + AC_TRY_LINK([#include <math.h> + #if __GNUC__ >= 4 + # undef isnanl + # define isnanl(x) __builtin_isnanl ((long double)(x)) + #elif defined isnan + # undef isnanl + # define isnanl(x) isnan ((long double)(x)) + #endif + long double x;], + [return isnanl (x);], + [gl_cv_func_isnanl_no_libm=yes], + [gl_cv_func_isnanl_no_libm=no]) + ]) +]) + +dnl Test whether isnanl() can be used with libm. +AC_DEFUN([gl_HAVE_ISNANL_IN_LIBM], +[ + AC_CACHE_CHECK([whether isnan(long double) can be used with libm], + [gl_cv_func_isnanl_in_libm], + [ + save_LIBS="$LIBS" + LIBS="$LIBS -lm" + AC_TRY_LINK([#include <math.h> + #if __GNUC__ >= 4 + # undef isnanl + # define isnanl(x) __builtin_isnanl ((long double)(x)) + #elif defined isnan + # undef isnanl + # define isnanl(x) isnan ((long double)(x)) + #endif + long double x;], + [return isnanl (x);], + [gl_cv_func_isnanl_in_libm=yes], + [gl_cv_func_isnanl_in_libm=no]) + LIBS="$save_LIBS" + ]) +]) + +dnl Test whether isnanl() recognizes all numbers which are neither finite nor +dnl infinite. This test fails e.g. on NetBSD/i386 and on glibc/ia64. +dnl Also, the GCC >= 4.0 built-in __builtin_isnanl does not pass the tests +dnl - for pseudo-denormals on i686 and x86_64, +dnl - for pseudo-zeroes, unnormalized numbers, and pseudo-denormals on ia64. +AC_DEFUN([gl_FUNC_ISNANL_WORKS], +[ + AC_REQUIRE([AC_PROG_CC]) + AC_REQUIRE([gl_BIGENDIAN]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CACHE_CHECK([whether isnanl works], [gl_cv_func_isnanl_works], + [ + AC_TRY_RUN([ +#include <float.h> +#include <limits.h> +#include <math.h> +#if __GNUC__ >= 4 +# undef isnanl +# define isnanl(x) __builtin_isnanl ((long double)(x)) +#elif defined isnan +# undef isnanl +# define isnanl(x) isnan ((long double)(x)) +#endif +#define NWORDS \ + ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) +typedef union { unsigned int word[NWORDS]; long double value; } + memory_long_double; +/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the + runtime type conversion. */ +#ifdef __sgi +static long double NaNl () +{ + double zero = 0.0; + return zero / zero; +} +#else +# define NaNl() (0.0L / 0.0L) +#endif +int main () +{ + memory_long_double m; + unsigned int i; + + if (!isnanl (NaNl ())) + return 1; + + /* The isnanl function should be immune against changes in the sign bit and + in the mantissa bits. The xor operation twiddles a bit that can only be + a sign bit or a mantissa bit (since the exponent never extends to + bit 31). */ + m.value = NaNl (); + m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); + for (i = 0; i < NWORDS; i++) + m.word[i] |= 1; + if (!isnanl (m.value)) + return 1; + +#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) +/* Representation of an 80-bit 'long double' as an initializer for a sequence + of 'unsigned int' words. */ +# ifdef WORDS_BIGENDIAN +# define LDBL80_WORDS(exponent,manthi,mantlo) \ + { ((unsigned int) (exponent) << 16) | ((unsigned int) (manthi) >> 16), \ + ((unsigned int) (manthi) << 16) | (unsigned int) (mantlo) >> 16), \ + (unsigned int) (mantlo) << 16 \ + } +# else +# define LDBL80_WORDS(exponent,manthi,mantlo) \ + { mantlo, manthi, exponent } +# endif + { /* Quiet NaN. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + { + /* Signalling NaN. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + /* The isnanl function should recognize Pseudo-NaNs, Pseudo-Infinities, + Pseudo-Zeroes, Unnormalized Numbers, and Pseudo-Denormals, as defined in + Intel IA-64 Architecture Software Developer's Manual, Volume 1: + Application Architecture. + Table 5-2 "Floating-Point Register Encodings" + Figure 5-6 "Memory to Floating-Point Register Data Translation" + */ + { /* Pseudo-NaN. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + { /* Pseudo-Infinity. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + { /* Pseudo-Zero. */ + static memory_long_double x = + { LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + { /* Unnormalized number. */ + static memory_long_double x = + { LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } + { /* Pseudo-Denormal. */ + static memory_long_double x = + { LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) }; + if (!isnanl (x.value)) + return 1; + } +#endif + + return 0; +}], [gl_cv_func_isnanl_works=yes], [gl_cv_func_isnanl_works=no], + [case "$host_cpu" in + # Guess no on ia64, x86_64, i386. + ia64 | x86_64 | i*86) gl_cv_func_isnanl_works="guessing no";; + *) + case "$host_os" in + netbsd*) gl_cv_func_isnanl_works="guessing no";; + *) gl_cv_func_isnanl_works="guessing yes";; + esac + ;; + esac + ]) + ]) +]) |