Mercurial > hg > octave-lojdl > gnulib-hg
changeset 8917:296a84124dcd
Recognize non-IEEE numbers on i386, x86_64, ia64.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Wed, 06 Jun 2007 02:02:41 +0000 |
parents | 353e81af4858 |
children | faef119238ca |
files | ChangeLog lib/isnan.c m4/isnanl.m4 tests/test-isnanl.h |
diffstat | 4 files changed, 185 insertions(+), 11 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2007-06-05 Bruno Haible <bruno@clisp.org> + + Fix isnanl so that it recognizes non-IEEE numbers on i386, x86_64, ia64. + * m4/isnanl.m4 (gl_FUNC_ISNANL_WORKS): Require AC_C_BIGENDIAN. Tested + non-IEEE numbers on i386, x86_64, ia64. + (gl_LONG_DOUBLE_EXPONENT_LOCATION): Require AC_C_BIGENDIAN. + * lib/isnan.c (FUNC): Add special code for i386, x86_64, ia64. + * tests/test-isnanl.h: Include float.h. + (main): Check also non-IEEE numbers on i386, x86_64, ia64. + 2007-06-05 Bruno Haible <bruno@clisp.org> * lib/vasnprintf.c (VASNPRINTF): Do the extra handling of NaN and Inf
--- a/lib/isnan.c +++ b/lib/isnan.c @@ -72,9 +72,41 @@ FUNC (DOUBLE x) { #ifdef KNOWN_EXPBIT0_LOCATION +# if defined USE_LONG_DOUBLE && ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) + /* Special CPU dependent code is needed to treat bit patterns outside the + IEEE 754 specification (such as Pseudo-NaNs, Pseudo-Infinities, + Pseudo-Zeroes, Unnormalized Numbers, and Pseudo-Denormals) as NaNs. + These bit patterns are: + - exponent = 0x0001..0x7FFF, mantissa bit 63 = 0, + - exponent = 0x0000, mantissa bit 63 = 1. + The NaN bit pattern is: + - exponent = 0x7FFF, mantissa >= 0x8000000000000001. */ + memory_double m; + unsigned int exponent; + + m.value = x; + exponent = (m.word[EXPBIT0_WORD] >> EXPBIT0_BIT) & EXP_MASK; +# ifdef WORDS_BIGENDIAN + /* Big endian: EXPBIT0_WORD = 0, EXPBIT0_BIT = 16. */ + if (exponent == 0) + return 1 & (m.word[0] >> 15); + else if (exponent == EXP_MASK) + return (((m.word[0] ^ 0x8000U) << 16) | m.word[1] | (m.word[2] >> 16)) != 0; + else + return 1 & ~(m.word[0] >> 15); +# else + /* Little endian: EXPBIT0_WORD = 2, EXPBIT0_BIT = 0. */ + if (exponent == 0) + return (m.word[1] >> 31); + else if (exponent == EXP_MASK) + return ((m.word[1] ^ 0x80000000U) | m.word[0]) != 0; + else + return (m.word[1] >> 31) ^ 1; +# endif +# else /* Be careful to not do any floating-point operation on x, such as x == x, because x may be a signaling NaN. */ -# if defined __SUNPRO_C || defined __DECC || (defined __sgi && !defined __GNUC__) +# if defined __SUNPRO_C || defined __DECC || (defined __sgi && !defined __GNUC__) /* The Sun C 5.0 compilers and the Compaq (ex-DEC) 6.4 compilers don't recognize the initializers as constant expressions. The latter compiler also fails when constant-folding 0.0 / 0.0 even when constant-folding is @@ -85,11 +117,11 @@ DOUBLE plus_inf = L_(1.0) / L_(0.0); DOUBLE minus_inf = -L_(1.0) / L_(0.0); nan.value = zero / zero; -# else +# else static memory_double nan = { L_(0.0) / L_(0.0) }; static DOUBLE plus_inf = L_(1.0) / L_(0.0); static DOUBLE minus_inf = -L_(1.0) / L_(0.0); -# endif +# endif { memory_double m; @@ -104,6 +136,7 @@ else return 0; } +# endif #else /* The configuration did not find sufficient information. Give up about the signaling NaNs, handle only the quiet NaNs. */
--- a/m4/isnanl.m4 +++ b/m4/isnanl.m4 @@ -1,4 +1,4 @@ -# isnanl.m4 serial 3 +# isnanl.m4 serial 4 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, @@ -97,14 +97,16 @@ ]) dnl Test whether isnanl() recognizes all numbers which are neither finite nor -dnl infinite. This test fails e.g. on NetBSD/i386. +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 <float.h> #include <limits.h> #include <math.h> #ifdef isnan @@ -113,7 +115,7 @@ #endif #define NWORDS \ ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) -typedef union { long double value; unsigned int word[NWORDS]; } +typedef union { unsigned int word[NWORDS]; long double value; } memory_long_double; int main () { @@ -131,6 +133,71 @@ 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_os" in @@ -143,6 +210,7 @@ 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], [
--- a/tests/test-isnanl.h +++ b/tests/test-isnanl.h @@ -17,6 +17,7 @@ /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ +#include <float.h> #include <limits.h> #include <stdio.h> #include <stdlib.h> @@ -35,6 +36,11 @@ int main () { + #define NWORDS \ + ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) + typedef union { unsigned int word[NWORDS]; long double value; } + memory_long_double; + /* Finite values. */ ASSERT (!isnanl (3.141L)); ASSERT (!isnanl (3.141e30L)); @@ -47,13 +53,11 @@ ASSERT (!isnanl (-1.0L / 0.0L)); /* Quiet NaN. */ ASSERT (isnanl (0.0L / 0.0L)); + #if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT - /* Signalling NaN. */ + /* A bit pattern that is different from a Quiet NaN. With a bit of luck, + it's a Signalling NaN. */ { - #define NWORDS \ - ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) - typedef union { long double value; unsigned int word[NWORDS]; } - memory_long_double; memory_long_double m; m.value = 0.0L / 0.0L; # if LDBL_EXPBIT0_BIT > 0 @@ -67,5 +71,64 @@ ASSERT (isnanl (m.value)); } #endif + +#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) }; + ASSERT (isnanl (x.value)); + } + { + /* Signalling NaN. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) }; + ASSERT (isnanl (x.value)); + } + /* 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) }; + ASSERT (isnanl (x.value)); + } + { /* Pseudo-Infinity. */ + static memory_long_double x = + { LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) }; + ASSERT (isnanl (x.value)); + } + { /* Pseudo-Zero. */ + static memory_long_double x = + { LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) }; + ASSERT (isnanl (x.value)); + } + { /* Unnormalized number. */ + static memory_long_double x = + { LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) }; + ASSERT (isnanl (x.value)); + } + { /* Pseudo-Denormal. */ + static memory_long_double x = + { LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) }; + ASSERT (isnanl (x.value)); + } +#endif + return 0; }