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author | Joseph Myers <joseph@codesourcery.com> | 2017-08-31 16:39:25 +0000 |
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committer | Joseph Myers <joseph@codesourcery.com> | 2017-08-31 16:39:25 +0000 |
commit | c0c49d60cfeff3b2aa801d6598143a073989654a (patch) | |
tree | 248bd1a808a8f2e27396ddfd1c04e5362d7e5da2 | |
parent | 5ef1b2138d4236bb3616e612c5bc4dc328a9ffb2 (diff) | |
download | glibc-c0c49d60cfeff3b2aa801d6598143a073989654a.zip glibc-c0c49d60cfeff3b2aa801d6598143a073989654a.tar.gz glibc-c0c49d60cfeff3b2aa801d6598143a073989654a.tar.bz2 |
Simplify NAN definitions.
Similar to my patches for HUGE_VAL and INFINITY. this patch eliminates
the bits/nan.h headers. __builtin_nanf ("") is used to define NAN for
GCC 3.3 and later; the fallback is (0.0f / 0.0f), which is a constant
expression for a quiet NaN of type float, but raises a spurious
"invalid" exception outside static initializers, which seems the best
that can be done purely in standard C. Again, if anyone actually uses
a compiler with its own incompatible extension for producing a
constant quiet NaN, we can add compiler conditionals.
Tested for x86_64.
* math/math.h [__USE_ISOC99] (NAN): Define directly here. Do not
include <bits/nan.h>.
* math/Makefile (headers): Remove bits/nan.h.
* bits/nan.h: Remove.
* sysdeps/ieee754/bits/nan.h: Likewise.
* sysdeps/mips/bits/nan.h: Likewise.
-rw-r--r-- | ChangeLog | 7 | ||||
-rw-r--r-- | bits/nan.h | 5 | ||||
-rw-r--r-- | math/Makefile | 1 | ||||
-rw-r--r-- | math/math.h | 11 | ||||
-rw-r--r-- | sysdeps/ieee754/bits/nan.h | 52 | ||||
-rw-r--r-- | sysdeps/mips/bits/nan.h | 67 |
6 files changed, 16 insertions, 127 deletions
@@ -1,5 +1,12 @@ 2017-08-31 Joseph Myers <joseph@codesourcery.com> + * math/math.h [__USE_ISOC99] (NAN): Define directly here. Do not + include <bits/nan.h>. + * math/Makefile (headers): Remove bits/nan.h. + * bits/nan.h: Remove. + * sysdeps/ieee754/bits/nan.h: Likewise. + * sysdeps/mips/bits/nan.h: Likewise. + * math/math.h [__USE_ISOC99] (INFINITY): Define directly here. Do not include <bits/inf.h>. * math/Makefile (headers): Remove bits/inf.h. diff --git a/bits/nan.h b/bits/nan.h deleted file mode 100644 index ab38168..0000000 --- a/bits/nan.h +++ /dev/null @@ -1,5 +0,0 @@ -#ifndef _MATH_H -#error "Never use <bits/nan.h> directly; include <math.h> instead." -#endif - -/* This file should define `NAN' on machines that have such things. */ diff --git a/math/Makefile b/math/Makefile index b9a06f0..0601f3a 100644 --- a/math/Makefile +++ b/math/Makefile @@ -23,7 +23,6 @@ include ../Makeconfig # Installed header files. headers := math.h bits/mathcalls.h bits/mathinline.h \ - bits/nan.h \ fpu_control.h complex.h bits/cmathcalls.h fenv.h \ bits/fenv.h bits/fenvinline.h bits/mathdef.h tgmath.h \ bits/math-finite.h bits/math-vector.h \ diff --git a/math/math.h b/math/math.h index 5f5a498..bbc1ab9 100644 --- a/math/math.h +++ b/math/math.h @@ -65,8 +65,15 @@ __BEGIN_DECLS # define INFINITY HUGE_VALF # endif -/* Get machine-dependent NAN value (returned for some domain errors). */ -# include <bits/nan.h> +/* IEEE Not A Number. */ +# if __GNUC_PREREQ (3, 3) +# define NAN (__builtin_nanf ("")) +# else +/* This will raise an "invalid" exception outside static initializers, + but is the best that can be done in ISO C while remaining a + constant expression. */ +# define NAN (0.0f / 0.0f) +# endif #endif /* __USE_ISOC99 */ #if __GLIBC_USE (IEC_60559_BFP_EXT) diff --git a/sysdeps/ieee754/bits/nan.h b/sysdeps/ieee754/bits/nan.h deleted file mode 100644 index b6e14f5..0000000 --- a/sysdeps/ieee754/bits/nan.h +++ /dev/null @@ -1,52 +0,0 @@ -/* `NAN' constant for IEEE 754 machines. - Copyright (C) 1992-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _MATH_H -# error "Never use <bits/nan.h> directly; include <math.h> instead." -#endif - - -/* IEEE Not A Number. */ - -#if __GNUC_PREREQ(3,3) - -# define NAN (__builtin_nanf ("")) - -#elif defined __GNUC__ - -# define NAN \ - (__extension__ \ - ((union { unsigned __l __attribute__ ((__mode__ (__SI__))); float __d; }) \ - { __l: 0x7fc00000UL }).__d) - -#else - -# include <endian.h> - -# if __BYTE_ORDER == __BIG_ENDIAN -# define __qnan_bytes { 0x7f, 0xc0, 0, 0 } -# endif -# if __BYTE_ORDER == __LITTLE_ENDIAN -# define __qnan_bytes { 0, 0, 0xc0, 0x7f } -# endif - -static union { unsigned char __c[4]; float __d; } __qnan_union - __attribute__ ((__unused__)) = { __qnan_bytes }; -# define NAN (__qnan_union.__d) - -#endif /* GCC. */ diff --git a/sysdeps/mips/bits/nan.h b/sysdeps/mips/bits/nan.h deleted file mode 100644 index a4a1ef9..0000000 --- a/sysdeps/mips/bits/nan.h +++ /dev/null @@ -1,67 +0,0 @@ -/* `NAN' constant for IEEE 754 machines. MIPS version. - Copyright (C) 1992-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _MATH_H -# error "Never use <bits/nan.h> directly; include <math.h> instead." -#endif - - -/* IEEE Not A Number. */ -/* In legacy-NaN mode MIPS has the qNaN and sNaN patterns reversed - compared to most other architectures. IEEE 754-1985 left the - definition of this open to implementations, and for MIPS the top bit - of the mantissa must be SET to indicate a sNaN. In 2008-NaN mode - MIPS aligned to IEEE 754-2008. */ - -#if __GNUC_PREREQ(3,3) - -# define NAN (__builtin_nanf ("")) - -#elif defined __GNUC__ - -/* No 2008-NaN mode support in any GCC version before 4.9. */ - -# define NAN \ - (__extension__ \ - ((union { unsigned __l __attribute__ ((__mode__ (__SI__))); float __d; }) \ - { __l: 0x7fbfffffUL }).__d) - -#else - -# include <endian.h> - -# if __BYTE_ORDER == __BIG_ENDIAN -# ifdef __mips_nan2008 -# define __qnan_bytes { 0x7f, 0xc0, 0, 0 } -# else -# define __qnan_bytes { 0x7f, 0xbf, 0xff, 0xff } -# endif -# endif -# if __BYTE_ORDER == __LITTLE_ENDIAN -# ifdef __mips_nan2008 -# define __qnan_bytes { 0, 0, 0xc0, 0x7f } -# else -# define __qnan_bytes { 0xff, 0xff, 0xbf, 0x7f } -# endif -# endif - -static union { unsigned char __c[4]; float __d; } __qnan_union - __attribute__ ((__unused__)) = { __qnan_bytes }; -# define NAN (__qnan_union.__d) - -#endif /* GCC. */ |