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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 
     22 /*
     23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
     24  * Use is subject to license terms.
     25  */
     26 
     27 	.file	"gettimeofday.s"
     28 
     29 #include "SYS.h"
     30 
     31 	ANSI_PRAGMA_WEAK(gettimeofday,function)
     32 
     33 /
     34 /  implements int gettimeofday(struct timeval *tp, void *tzp)
     35 /
     36 /	note that tzp is always ignored
     37 /
     38 
     39 	ENTRY(gettimeofday)
     40 /
     41 /	use long long gethrestime()
     42 /
     43 	SYSFASTTRAP(GETHRESTIME)
     44 /
     45 /	gethrestime trap returns seconds in %eax, nsecs in %edx
     46 /	need to convert nsecs to usecs & store into area pointed
     47 /	to by struct timeval * argument.
     48 /
     49 	movl 4(%esp), %ecx	/ put ptr to timeval in %ecx
     50 	jecxz 1f		/ bail if we get a null pointer
     51 	movl %eax, (%ecx)	/ store seconds into timeval ptr
     52 	movl $274877907, %eax	/ divide by 1000 as impl. by gcc
     53 	imull %edx		/ See Hacker's Delight pg 162
     54 	sarl $6, %edx		/ simplified by 0 <= nsec <= 1e9
     55 	movl %edx, 4(%ecx)	/ store usecs into timeval ptr + 4.
     56 1:
     57 	RETC			/ return 0
     58 	SET_SIZE(gettimeofday)
     59 
     60 
     61