glibc/bits/fp-logb.h

29 lines
1.2 KiB
C
Raw Normal View History

Refactor FP_ILOGB* out of bits/mathdef.h. Continuing the refactoring of bits/mathdef.h, this patch stops it defining FP_ILOGB0 and FP_ILOGBNAN, moving the required information to a new header bits/fp-logb.h. There are only two possible values of each of those macros permitted by ISO C. TS 18661-1 adds corresponding macros for llogb, and their values are required to correspond to those of the ilogb macros in the obvious way. Thus two boolean values - for which the same choices are correct for most architectures - suffice to determine the value of all these macros, and by defining macros for those boolean values in bits/fp-logb.h we can then define the public FP_* macros in math.h and avoid the present duplication of the associated feature test macro logic. This patch duly moves to bits/fp-logb.h defining __FP_LOGB0_IS_MIN and __FP_LOGBNAN_IS_MIN. Default definitions of those to 0 are correct for both architectures, while ia64, m68k and x86 get their own versions of bits/fp-logb.h to reflect their use of values different from the defaults. The patch renders many copies of bits/mathdef.h trivial (needed only to avoid the default __NO_LONG_DOUBLE_MATH). I'll revise <https://sourceware.org/ml/libc-alpha/2016-11/msg00865.html> accordingly so that it removes all bits/mathdef.h headers except the default one and the alpha one, and arranges for the header to be included only by complex.h as the only remaining use at that point will be for the alpha ABI issues there. Tested for x86_64 and x86. Also did compile-only testing with build-many-glibcs.py (using glibc sources from before the commit that introduced many build failures with undefined __GI___sigsetjmp). * bits/fp-logb.h: New file. * sysdeps/ia64/bits/fp-logb.h: Likewise. * sysdeps/m68k/m680x0/bits/fp-logb.h: Likewise. * sysdeps/x86/bits/fp-logb.h: Likewise. * math/Makefile (headers): Add bits/fp-logb.h. * math/math.h: Include <bits/fp-logb.h>. [__USE_ISOC99] (FP_ILOGB0): Define based on __FP_LOGB0_IS_MIN. [__USE_ISOC99] (FP_ILOGBNAN): Define based on __FP_LOGBNAN_IS_MIN. * bits/mathdef.h (FP_ILOGB0): Remove. (FP_ILOGBNAN): Likewise. * sysdeps/aarch64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/alpha/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/ia64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/m68k/m680x0/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/mips/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/powerpc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/s390/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/sparc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/x86/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise.
2016-12-01 02:56:55 +00:00
/* Define __FP_LOGB0_IS_MIN and __FP_LOGBNAN_IS_MIN.
Copyright (C) 2016-2019 Free Software Foundation, Inc.
Refactor FP_ILOGB* out of bits/mathdef.h. Continuing the refactoring of bits/mathdef.h, this patch stops it defining FP_ILOGB0 and FP_ILOGBNAN, moving the required information to a new header bits/fp-logb.h. There are only two possible values of each of those macros permitted by ISO C. TS 18661-1 adds corresponding macros for llogb, and their values are required to correspond to those of the ilogb macros in the obvious way. Thus two boolean values - for which the same choices are correct for most architectures - suffice to determine the value of all these macros, and by defining macros for those boolean values in bits/fp-logb.h we can then define the public FP_* macros in math.h and avoid the present duplication of the associated feature test macro logic. This patch duly moves to bits/fp-logb.h defining __FP_LOGB0_IS_MIN and __FP_LOGBNAN_IS_MIN. Default definitions of those to 0 are correct for both architectures, while ia64, m68k and x86 get their own versions of bits/fp-logb.h to reflect their use of values different from the defaults. The patch renders many copies of bits/mathdef.h trivial (needed only to avoid the default __NO_LONG_DOUBLE_MATH). I'll revise <https://sourceware.org/ml/libc-alpha/2016-11/msg00865.html> accordingly so that it removes all bits/mathdef.h headers except the default one and the alpha one, and arranges for the header to be included only by complex.h as the only remaining use at that point will be for the alpha ABI issues there. Tested for x86_64 and x86. Also did compile-only testing with build-many-glibcs.py (using glibc sources from before the commit that introduced many build failures with undefined __GI___sigsetjmp). * bits/fp-logb.h: New file. * sysdeps/ia64/bits/fp-logb.h: Likewise. * sysdeps/m68k/m680x0/bits/fp-logb.h: Likewise. * sysdeps/x86/bits/fp-logb.h: Likewise. * math/Makefile (headers): Add bits/fp-logb.h. * math/math.h: Include <bits/fp-logb.h>. [__USE_ISOC99] (FP_ILOGB0): Define based on __FP_LOGB0_IS_MIN. [__USE_ISOC99] (FP_ILOGBNAN): Define based on __FP_LOGBNAN_IS_MIN. * bits/mathdef.h (FP_ILOGB0): Remove. (FP_ILOGBNAN): Likewise. * sysdeps/aarch64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/alpha/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/ia64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/m68k/m680x0/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/mips/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/powerpc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/s390/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/sparc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/x86/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise.
2016-12-01 02:56:55 +00:00
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/fp-logb.h> directly; include <math.h> instead."
#endif
/* __FP_LOGB0_IS_MIN is defined to 1 if FP_ILOGB0 is INT_MIN, and 0 if
it is -INT_MAX. __FP_LOGBNAN_IS_MIN is defined to 1 if FP_ILOGBNAN
is INT_MIN, and 0 if it is INT_MAX. */
#define __FP_LOGB0_IS_MIN 0
#define __FP_LOGBNAN_IS_MIN 0