glibc/sysdeps/x86_64/hp-timing.h
Roland McGrath fdc07525f4 [BZ #789]
2005-03-15  Jakub Jelinek  <jakub@redhat.com>
	[BZ #789]
	* sysdeps/i386/i686/hp-timing.h (HP_TIMING_ACCUM): Fix asm constraints.
	Remove memory clobber.

	* sysdeps/x86_64/hp-timing.h (HP_TIMING_ACCUM): Make the addition
	thread-safe.  Subtract GLRO(dl_hp_timing_overhead) from Diff.
2005-03-15 22:31:32 +00:00

42 lines
1.7 KiB
C

/* High precision, low overhead timing functions. x86-64 version.
Copyright (C) 2002, 2004, 2005 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _HP_TIMING_H
/* We can use some of the i686 implementation without changes. */
# include <sysdeps/i386/i686/hp-timing.h>
/* The "=A" constraint used in 32-bit mode does not work in 64-bit mode. */
# undef HP_TIMING_NOW
# define HP_TIMING_NOW(Var) \
({ unsigned int _hi, _lo; \
asm volatile ("rdtsc" : "=a" (_lo), "=d" (_hi)); \
(Var) = ((unsigned long long int) _hi << 32) | _lo; })
/* The funny business for 32-bit mode is not required here. */
# undef HP_TIMING_ACCUM
# define HP_TIMING_ACCUM(Sum, Diff) \
do { \
hp_timing_t __diff = (Diff) - GLRO(dl_hp_timing_overhead); \
__asm__ __volatile__ ("lock; addq %1, %0" \
: "=m" (Sum) : "r" (__diff), "m" (Sum)); \
} while (0)
#endif /* hp-timing.h */