alloca.s revision 9a70fc3be3b1e966bf78825cdb8d509963a6f0a1
/*
* 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 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.file "alloca.s"
#include "SYS.h"
ENTRY(__builtin_alloca)
popl %ecx / grab our return address
movl (%esp),%eax / get argument
addl $3,%eax
andl $0xfffffffc,%eax / round up to multiple of 4
subl %eax,%esp / leave requested space on stack
leal 4(%esp),%eax / adjust, accounting for the "size" arg
pushl %ecx / put back return address
ret
SET_SIZE(__builtin_alloca)