17c478bd9Sstevel@tonic-gate/* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*9a70fc3bSMark J. Nelson * Common Development and Distribution License (the "License"). 6*9a70fc3bSMark J. Nelson * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 217c478bd9Sstevel@tonic-gate/* 227c478bd9Sstevel@tonic-gate * Copyright (c) 1998, by Sun Microsystems, Inc. 237c478bd9Sstevel@tonic-gate * All rights reserved. 247c478bd9Sstevel@tonic-gate */ 257c478bd9Sstevel@tonic-gate 26*9a70fc3bSMark J. Nelson .file "alloca.s" 277c478bd9Sstevel@tonic-gate 287c478bd9Sstevel@tonic-gate#include <sys/asm_linkage.h> 297c478bd9Sstevel@tonic-gate#include <sys/stack.h> 307c478bd9Sstevel@tonic-gate 317c478bd9Sstevel@tonic-gate ! 327c478bd9Sstevel@tonic-gate ! o0: # bytes of space to allocate, already rounded to 0 mod 8 337c478bd9Sstevel@tonic-gate ! o1: %sp-relative offset of tmp area 347c478bd9Sstevel@tonic-gate ! o2: %sp-relative offset of end of tmp area 357c478bd9Sstevel@tonic-gate ! 367c478bd9Sstevel@tonic-gate ! we want to bump %sp by the requested size 377c478bd9Sstevel@tonic-gate ! then copy the tmp area to its new home 387c478bd9Sstevel@tonic-gate ! this is necessary as we could theoretically 397c478bd9Sstevel@tonic-gate ! be in the middle of a complicated expression. 407c478bd9Sstevel@tonic-gate ! 417c478bd9Sstevel@tonic-gate ENTRY(__builtin_alloca) 427c478bd9Sstevel@tonic-gate add %sp, STACK_BIAS, %g1 ! save current sp + STACK_BIAS 437c478bd9Sstevel@tonic-gate sub %sp, %o0, %sp ! bump to new value 447c478bd9Sstevel@tonic-gate add %sp, STACK_BIAS, %g5 457c478bd9Sstevel@tonic-gate ! copy loop: should do nothing gracefully 467c478bd9Sstevel@tonic-gate b 2f 477c478bd9Sstevel@tonic-gate subcc %o2, %o1, %o5 ! number of bytes to move 487c478bd9Sstevel@tonic-gate1: 497c478bd9Sstevel@tonic-gate ldx [%g1 + %o1], %o4 ! load from old temp area 507c478bd9Sstevel@tonic-gate stx %o4, [%g5 + %o1] ! store to new temp area 517c478bd9Sstevel@tonic-gate add %o1, 8, %o1 527c478bd9Sstevel@tonic-gate2: bg,pt %xcc, 1b 537c478bd9Sstevel@tonic-gate subcc %o5, 8, %o5 547c478bd9Sstevel@tonic-gate ! now return new %sp + end-of-temp 557c478bd9Sstevel@tonic-gate add %sp, %o2, %o0 567c478bd9Sstevel@tonic-gate retl 577c478bd9Sstevel@tonic-gate add %o0, STACK_BIAS, %o0 587c478bd9Sstevel@tonic-gate SET_SIZE(__builtin_alloca) 59