|
Packit Service |
9e899f |
/* High precision, low overhead timing functions. x86 version.
|
|
Packit Service |
9e899f |
Copyright (C) 2018 Free Software Foundation, Inc.
|
|
Packit |
6c4009 |
This file is part of the GNU C Library.
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
The GNU C Library is free software; you can redistribute it and/or
|
|
Packit |
6c4009 |
modify it under the terms of the GNU Lesser General Public
|
|
Packit |
6c4009 |
License as published by the Free Software Foundation; either
|
|
Packit |
6c4009 |
version 2.1 of the License, or (at your option) any later version.
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
The GNU C Library is distributed in the hope that it will be useful,
|
|
Packit |
6c4009 |
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
Packit |
6c4009 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Packit |
6c4009 |
Lesser General Public License for more details.
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
You should have received a copy of the GNU Lesser General Public
|
|
Packit |
6c4009 |
License along with the GNU C Library; if not, see
|
|
Packit |
6c4009 |
<http://www.gnu.org/licenses/>. */
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
#ifndef _HP_TIMING_H
|
|
Packit |
6c4009 |
#define _HP_TIMING_H 1
|
|
Packit |
6c4009 |
|
|
Packit Service |
9e899f |
#include <isa.h>
|
|
Packit Service |
9e899f |
|
|
Packit Service |
9e899f |
#if MINIMUM_ISA == 686 || MINIMUM_ISA == 8664
|
|
Packit |
6c4009 |
/* We always assume having the timestamp register. */
|
|
Packit Service |
9e899f |
# define HP_TIMING_AVAIL (1)
|
|
Packit Service |
9e899f |
# define HP_SMALL_TIMING_AVAIL (1)
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* We indeed have inlined functions. */
|
|
Packit Service |
9e899f |
# define HP_TIMING_INLINE (1)
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* We use 64bit values for the times. */
|
|
Packit |
6c4009 |
typedef unsigned long long int hp_timing_t;
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* That's quite simple. Use the `rdtsc' instruction. Note that the value
|
|
Packit |
6c4009 |
might not be 100% accurate since there might be some more instructions
|
|
Packit |
6c4009 |
running in this moment. This could be changed by using a barrier like
|
|
Packit |
6c4009 |
'cpuid' right before the `rdtsc' instruciton. But we are not interested
|
|
Packit Service |
f8acdb |
in accurate clock cycles here so we don't do this.
|
|
Packit Service |
f8acdb |
|
|
Packit Service |
f8acdb |
NB: Use __builtin_ia32_rdtsc directly since including <x86intrin.h>
|
|
Packit Service |
f8acdb |
makes building glibc very slow. */
|
|
Packit Service |
6bc0b2 |
# ifdef USE_RDTSCP
|
|
Packit Service |
6bc0b2 |
/* RDTSCP waits until all previous instructions have executed and all
|
|
Packit Service |
6bc0b2 |
previous loads are globally visible before reading the counter.
|
|
Packit Service |
6bc0b2 |
RDTSC doesn't wait until all previous instructions have been executed
|
|
Packit Service |
6bc0b2 |
before reading the counter. */
|
|
Packit Service |
6bc0b2 |
# define HP_TIMING_NOW(Var) \
|
|
Packit Service |
6bc0b2 |
(__extension__ ({ \
|
|
Packit Service |
6bc0b2 |
unsigned int __aux; \
|
|
Packit Service |
6bc0b2 |
(Var) = __builtin_ia32_rdtscp (&__aux); \
|
|
Packit Service |
6bc0b2 |
}))
|
|
Packit Service |
6bc0b2 |
# else
|
|
Packit Service |
6bc0b2 |
# define HP_TIMING_NOW(Var) ((Var) = __builtin_ia32_rdtsc ())
|
|
Packit Service |
6bc0b2 |
# endif
|
|
Packit |
6c4009 |
|
|
Packit Service |
9e899f |
# include <hp-timing-common.h>
|
|
Packit Service |
9e899f |
#else
|
|
Packit Service |
9e899f |
/* NB: Undefine _HP_TIMING_H so that <sysdeps/generic/hp-timing.h> will
|
|
Packit Service |
9e899f |
be included. */
|
|
Packit Service |
9e899f |
# undef _HP_TIMING_H
|
|
Packit Service |
9e899f |
# include <sysdeps/generic/hp-timing.h>
|
|
Packit Service |
9e899f |
#endif
|
|
Packit |
6c4009 |
|
|
Packit Service |
9e899f |
#endif /* hp-timing.h */
|