glibc/sysdeps/x86_64/hp-timing.h
2012-02-09 23:18:22 +00:00

41 lines
1.6 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, see
<http://www.gnu.org/licenses/>. */
#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 */