alloca.S revision 1.1
11.1Scgd/*- 21.1Scgd * Copyright (c) 1990 The Regents of the University of California. 31.1Scgd * All rights reserved. 41.1Scgd * 51.1Scgd * This code is derived from software contributed to Berkeley by 61.1Scgd * William Jolitz. 71.1Scgd * 81.1Scgd * Redistribution and use in source and binary forms, with or without 91.1Scgd * modification, are permitted provided that the following conditions 101.1Scgd * are met: 111.1Scgd * 1. Redistributions of source code must retain the above copyright 121.1Scgd * notice, this list of conditions and the following disclaimer. 131.1Scgd * 2. Redistributions in binary form must reproduce the above copyright 141.1Scgd * notice, this list of conditions and the following disclaimer in the 151.1Scgd * documentation and/or other materials provided with the distribution. 161.1Scgd * 3. All advertising materials mentioning features or use of this software 171.1Scgd * must display the following acknowledgement: 181.1Scgd * This product includes software developed by the University of 191.1Scgd * California, Berkeley and its contributors. 201.1Scgd * 4. Neither the name of the University nor the names of its contributors 211.1Scgd * may be used to endorse or promote products derived from this software 221.1Scgd * without specific prior written permission. 231.1Scgd * 241.1Scgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251.1Scgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261.1Scgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271.1Scgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281.1Scgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291.1Scgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301.1Scgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311.1Scgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321.1Scgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331.1Scgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341.1Scgd * SUCH DAMAGE. 351.1Scgd */ 361.1Scgd 371.1Scgd#if defined(LIBC_SCCS) && !defined(lint) 381.1Scgd .text 391.1Scgd /*.asciz "from: @(#)alloca.s 5.2 (Berkeley) 5/14/90"*/ 401.1Scgd .asciz "$Id: alloca.S,v 1.1 1993/10/07 00:18:59 cgd Exp $" 411.1Scgd#endif /* LIBC_SCCS and not lint */ 421.1Scgd 431.1Scgd/* like alloc, but automatic automatic free in return */ 441.1Scgd 451.1Scgd#include "DEFS.h" 461.1Scgd 471.1ScgdENTRY(alloca) 481.1Scgd popl %edx /* pop return addr */ 491.1Scgd popl %eax /* pop amount to allocate */ 501.1Scgd movl %esp,%ecx 511.1Scgd addl $3,%eax /* round up to next word */ 521.1Scgd andl $0xfffffffc,%eax 531.1Scgd subl %eax,%esp 541.1Scgd movl %esp,%eax /* base of newly allocated space */ 551.1Scgd pushl 8(%ecx) /* copy possible saved registers */ 561.1Scgd pushl 4(%ecx) 571.1Scgd pushl 0(%ecx) 581.1Scgd pushl %eax /* dummy to pop at callsite */ 591.1Scgd jmp %edx /* "return" */ 60