dnl  x86 pentium time stamp counter access routine.

dnl  Copyright 1999, 2000, 2003, 2004 Free Software Foundation, Inc.
dnl 
dnl  This file is part of the GNU MP Library.
dnl 
dnl  The GNU MP Library is free software; you can redistribute it and/or
dnl  modify it under the terms of the GNU Lesser General Public License as
dnl  published by the Free Software Foundation; either version 2.1 of the
dnl  License, or (at your option) any later version.
dnl 
dnl  The GNU MP Library is distributed in the hope that it will be useful,
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dnl  Lesser General Public License for more details.
dnl 
dnl  You should have received a copy of the GNU Lesser General Public
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dnl  not, write to the Free Software Foundation, Inc., 59 Temple Place -
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include(`../config.m4')


C void speed_cyclecounter (unsigned p[2]);
C
C Get the pentium rdtsc cycle counter, storing the least significant word in
C p[0] and the most significant in p[1].
C
C cpuid is used to serialize execution.  On big measurements this won't be
C significant but it may help make small single measurements more accurate.

PROLOGUE(speed_cyclecounter)

	C rdi	p

	movq	%rbx, %r10
	xorl	%eax, %eax
	cpuid
	rdtsc
	movl	%eax, (%rdi)
	movl	%edx, 4(%rdi)
	movq	%r10, %rbx
	ret
EPILOGUE()