X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2Fisnanl.m4;h=a02ded78b84fe900a745415dba181bf9f3aad7d2;hb=91562b11acd5306bf0a192e00c167ca6e332690d;hp=6c6b0d057bb3f9847e319d8797c7cdf4d81d9b44;hpb=89aab6dde9b5afaf958c645afa8a135466f8d4f7;p=gnulib.git diff --git a/m4/isnanl.m4 b/m4/isnanl.m4 index 6c6b0d057..a02ded78b 100644 --- a/m4/isnanl.m4 +++ b/m4/isnanl.m4 @@ -1,38 +1,222 @@ -# isnanl.m4 serial 1 +# isnanl.m4 serial 5 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. -AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM], +AC_DEFUN([gl_FUNC_ISNANL], [ - AC_REQUIRE([gt_TYPE_LONGDOUBLE]) - if test $gt_cv_c_long_double = yes; then - AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm], - [gl_cv_func_isnanl_no_libm], - [ - AC_TRY_LINK([#include - #ifdef 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]) - ]) - if test $gl_cv_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 - AC_LIBOBJ([isnanl]) - gl_LONG_DOUBLE_EXPONENT_LOCATION + 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 $gl_func_isnanl = yes; then + AC_DEFINE([HAVE_ISNANL], 1, + [Define if the isnan(long double) function is available.]) + else + AC_LIBOBJ([isnanl]) + gl_LONG_DOUBLE_EXPONENT_LOCATION + fi + AC_SUBST([ISNANL_LIBM]) +]) + +AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM], +[ + gl_HAVE_ISNANL_NO_LIBM + gl_func_isnanl_no_libm=$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 $gl_func_isnanl_no_libm = yes; then + AC_DEFINE([HAVE_ISNANL_IN_LIBC], 1, + [Define if the isnan(long double) function is available in libc.]) + else + AC_LIBOBJ([isnanl]) + gl_LONG_DOUBLE_EXPONENT_LOCATION + fi +]) + +dnl Test whether isnanl() can be used without libm. +AC_DEFUN([gl_HAVE_ISNANL_NO_LIBM], +[ + AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm], + [gl_cv_func_isnanl_no_libm], + [ + AC_TRY_LINK([#include + #ifdef isnan + # undef isnanl + # define isnanl(x) isnan ((long double)(x)) + #endif + long double x;], + [return isnanl (x);], + [gl_cv_func_isnanl_no_libm=yes], + [gl_cv_func_isnanl_no_libm=no]) + ]) +]) + +dnl Test whether isnanl() can be used with libm. +AC_DEFUN([gl_HAVE_ISNANL_IN_LIBM], +[ + AC_CACHE_CHECK([whether isnan(long double) can be used with libm], + [gl_cv_func_isnanl_in_libm], + [ + save_LIBS="$LIBS" + LIBS="$LIBS -lm" + AC_TRY_LINK([#include + #ifdef isnan + # undef isnanl + # define isnanl(x) isnan ((long double)(x)) + #endif + long double x;], + [return isnanl (x);], + [gl_cv_func_isnanl_in_libm=yes], + [gl_cv_func_isnanl_in_libm=no]) + LIBS="$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. +AC_DEFUN([gl_FUNC_ISNANL_WORKS], +[ + AC_REQUIRE([AC_PROG_CC]) + AC_REQUIRE([AC_C_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 +#include +#include +#ifdef 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; +int main () +{ + memory_long_double m; + unsigned int i; + + /* 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 = 0.0L / 0.0L; + 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 + ]) + ]) ]) AC_DEFUN([gl_LONG_DOUBLE_EXPONENT_LOCATION], [ + AC_REQUIRE([AC_C_BIGENDIAN]) AC_CACHE_CHECK([where to find the exponent in a 'long double'], [gl_cv_cc_long_double_expbit0], [