1*0d34bfa2Suebayasi/* $NetBSD: alloca.S,v 1.9 2014/05/23 02:34:19 uebayasi Exp $ */ 21394f01bSchristos 30b9f5089Scgd/*- 40b9f5089Scgd * Copyright (c) 1990 The Regents of the University of California. 50b9f5089Scgd * All rights reserved. 60b9f5089Scgd * 70b9f5089Scgd * This code is derived from software contributed to Berkeley by 80b9f5089Scgd * William Jolitz. 90b9f5089Scgd * 100b9f5089Scgd * Redistribution and use in source and binary forms, with or without 110b9f5089Scgd * modification, are permitted provided that the following conditions 120b9f5089Scgd * are met: 130b9f5089Scgd * 1. Redistributions of source code must retain the above copyright 140b9f5089Scgd * notice, this list of conditions and the following disclaimer. 150b9f5089Scgd * 2. Redistributions in binary form must reproduce the above copyright 160b9f5089Scgd * notice, this list of conditions and the following disclaimer in the 170b9f5089Scgd * documentation and/or other materials provided with the distribution. 18eb7c1594Sagc * 3. Neither the name of the University nor the names of its contributors 190b9f5089Scgd * may be used to endorse or promote products derived from this software 200b9f5089Scgd * without specific prior written permission. 210b9f5089Scgd * 220b9f5089Scgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 230b9f5089Scgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 240b9f5089Scgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 250b9f5089Scgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 260b9f5089Scgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 270b9f5089Scgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 280b9f5089Scgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 290b9f5089Scgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 300b9f5089Scgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 310b9f5089Scgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 320b9f5089Scgd * SUCH DAMAGE. 33823c3657Sjtc * 34823c3657Sjtc * from: @(#)alloca.s 5.2 (Berkeley) 5/14/90 350b9f5089Scgd */ 360b9f5089Scgd 373f78e35cSjtc#include <machine/asm.h> 38823c3657Sjtc#if defined(LIBC_SCCS) 39*0d34bfa2Suebayasi RCSID("$NetBSD: alloca.S,v 1.9 2014/05/23 02:34:19 uebayasi Exp $") 40823c3657Sjtc#endif 410b9f5089Scgd 42c39d2055Satatat/* like alloc, but automatic free in return */ 430b9f5089Scgd 440b9f5089ScgdENTRY(alloca) 450b9f5089Scgd popl %edx /* pop return addr */ 460b9f5089Scgd popl %eax /* pop amount to allocate */ 470b9f5089Scgd movl %esp,%ecx 480b9f5089Scgd addl $3,%eax /* round up to next word */ 499c8862a9Smycroft andl $-4,%eax 500b9f5089Scgd subl %eax,%esp 510b9f5089Scgd movl %esp,%eax /* base of newly allocated space */ 520b9f5089Scgd pushl 8(%ecx) /* copy possible saved registers */ 530b9f5089Scgd pushl 4(%ecx) 540b9f5089Scgd pushl 0(%ecx) 550b9f5089Scgd pushl %eax /* dummy to pop at callsite */ 5670d3133eSross jmp *%edx /* "return" */ 57*0d34bfa2SuebayasiEND(alloca) 58