alloca.S revision 1.4.16.1
1 /* $NetBSD: alloca.S,v 1.4.16.1 2007/08/28 17:36:30 matt Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Mark Brinicombe 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Mark Brinicombe 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /* like alloc, but automatic automatic free in return */ 36 37 #include <machine/asm.h> 38 39 RCSID("$NetBSD: alloca.S,v 1.4.16.1 2007/08/28 17:36:30 matt Exp $") 40 41 ENTRY(alloca) 42 #ifdef __thumb__ 43 mov r1, #0x00000007 44 add r0, r0, r1 /* round up to next 8 byte alignment */ 45 bic r0, r0, r1 46 mov r1, sp /* can't maniuplate the SP directly */ 47 sub r0, r1, r0 /* Adjust the stack pointer */ 48 mov sp, r0 /* and update it */ 49 #else 50 add r0, r0, #0x00000007 /* round up to next 8 byte alignment */ 51 bic r0, r0, #0x00000007 52 sub sp, sp, r0 /* Adjust the stack pointer */ 53 mov r0, sp /* r0 = base of new space */ 54 #endif 55 RET 56 .size alloca, .-alloca 57
Indexes created Sat Nov 08 12:09:53 GMT 2025