/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
*/
.file "gettimeofday.s"
#include "SYS.h"
ANSI_PRAGMA_WEAK(gettimeofday,function)
/*
* implements int gettimeofday(struct timeval *tp, void *tzp)
*
* note that tzp is always ignored
*/
/*
* gettimeofday is implemented as an alternate capability symbol
* on x86 systems which support the rdtscp instruction.
*/
ENTRY(gettimeofday)
/*
* use long long gethrestime()
*/
pushq %rdi /* pointer to timeval */
SYSFASTTRAP(GETHRESTIME)
/*
* gethrestime trap returns seconds in %eax, nsecs in %edx
* need to convert nsecs to usecs & store into area pointed
* to by struct timeval * argument.
*/
popq %rcx /* pointer to timeval */
jrcxz 1f /* bail if we get a null pointer */
movq %rax, (%rcx) /* store seconds into timeval ptr */
movl $274877907, %eax /* divide by 1000 as impl. by gcc */
imull %edx /* See Hacker's Delight pg 162 */
sarl $6, %edx /* simplified by 0 <= nsec <= 1e9 */
movq %rdx, 8(%rcx) /* store usecs into timeval ptr + 8. */
1:
RETC /* return 0 */
SET_SIZE(gettimeofday)