glibc/sysdeps/x86/fpu/math-barriers.h
Joseph Myers 9ed2e15ff4 Move math_opt_barrier, math_force_eval to separate math-barriers.h.
This patch continues cleaning up math_private.h by moving the
math_opt_barrier and math_force_eval macros to a separate header
math-barriers.h.

At present, those macros are inside a "#ifndef math_opt_barrier" in
math_private.h to allow architectures to override them and then use
a separate math-barriers.h header, no such #ifndef or #include_next is
needed; architectures just have their own alternative version of
math-barriers.h when providing their own optimized versions that avoid
going through memory unnecessarily.  The generic math-barriers.h has a
comment added to document these two macros.

In this patch, math_private.h is made to #include <math-barriers.h>,
so files using these macros do not need updating yet.  That is because
of uses of math_force_eval in math_check_force_underflow and
math_check_force_underflow_nonneg, which are still defined in
math_private.h.  Once those are moved out to a separate header, that
separate header can be made to include <math-barriers.h>, as can the
other files directly using these barrier macros, and then the include
of <math-barriers.h> from math_private.h can be removed.

Tested for x86_64 and x86.  Also tested with build-many-glibcs.py that
installed stripped shared libraries are unchanged by this patch.

	* sysdeps/generic/math-barriers.h: New file.
	* sysdeps/generic/math_private.h [!math_opt_barrier]
	(math_opt_barrier): Move to math-barriers.h.
	[!math_opt_barrier] (math_force_eval): Likewise.
	* sysdeps/aarch64/fpu/math-barriers.h: New file.
	* sysdeps/aarch64/fpu/math_private.h (math_opt_barrier): Move to
	math-barriers.h.
	(math_force_eval): Likewise.
	* sysdeps/alpha/fpu/math-barriers.h: New file.
	* sysdeps/alpha/fpu/math_private.h (math_opt_barrier): Move to
	math-barriers.h.
	(math_force_eval): Likewise.
	* sysdeps/x86/fpu/math-barriers.h: New file.
	* sysdeps/i386/fpu/fenv_private.h (math_opt_barrier): Move to
	math-barriers.h.
	(math_force_eval): Likewise.
	* sysdeps/m68k/m680x0/fpu/math_private.h: Move to....
	* sysdeps/m68k/m680x0/fpu/math-barriers.h: ... here.  Adjust
	multiple-include guard for rename.
	* sysdeps/powerpc/fpu/math-barriers.h: New file.
	* sysdeps/powerpc/fpu/math_private.h (math_opt_barrier): Move to
	math-barriers.h.
	(math_force_eval): Likewise.
2018-05-09 19:45:47 +00:00

62 lines
2.1 KiB
C

/* Control when floating-point expressions are evaluated. x86 version.
Copyright (C) 2007-2018 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 X86_MATH_BARRIERS_H
#define X86_MATH_BARRIERS_H 1
#ifdef __SSE2_MATH__
# define math_opt_barrier(x) \
({ __typeof(x) __x; \
if (sizeof (x) <= sizeof (double) \
|| __builtin_types_compatible_p (__typeof (x), _Float128)) \
__asm ("" : "=x" (__x) : "0" (x)); \
else \
__asm ("" : "=t" (__x) : "0" (x)); \
__x; })
# define math_force_eval(x) \
do { \
if (sizeof (x) <= sizeof (double) \
|| __builtin_types_compatible_p (__typeof (x), _Float128)) \
__asm __volatile ("" : : "x" (x)); \
else \
__asm __volatile ("" : : "f" (x)); \
} while (0)
#else
# define math_opt_barrier(x) \
({ __typeof (x) __x; \
if (__builtin_types_compatible_p (__typeof (x), _Float128)) \
{ \
__x = (x); \
__asm ("" : "+m" (__x)); \
} \
else \
__asm ("" : "=t" (__x) : "0" (x)); \
__x; })
# define math_force_eval(x) \
do { \
__typeof (x) __x = (x); \
if (sizeof (x) <= sizeof (double) \
|| __builtin_types_compatible_p (__typeof (x), _Float128)) \
__asm __volatile ("" : : "m" (__x)); \
else \
__asm __volatile ("" : : "f" (__x)); \
} while (0)
#endif
#endif