xref: /titanic_41/usr/src/lib/libc/amd64/gen/setjmp.s (revision 2449e17f82f6097fd2c665b64723e31ceecbeca6)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27	.ident	"%Z%%M%	%I%	%E% SMI"
28
29	.file	"%M%"
30
31/*
32 *	longjmp(env, val)
33 * will generate a "return(val)" from
34 * the last call to
35 *	setjmp(env)
36 * by restoring registers rip rsp rbp rbx r12 r13 r14 r15 from 'env'
37 * and doing a return.
38 */
39
40/*
41 * entry    reg   offset
42 * env[0] = %rbx  0	register variables
43 * env[1] = %r12  8
44 * env[2] = %r13  16
45 * env[3] = %r14  24
46 * env[4] = %r15  32
47 * env[5] = %rbp  40	stack frame
48 * env[6] = %rsp  48
49 * env[7] = %rip  56
50 */
51
52#include <sys/asm_linkage.h>
53
54	ANSI_PRAGMA_WEAK(setjmp,function)
55	ANSI_PRAGMA_WEAK(longjmp,function)
56
57#include "SYS.h"
58
59	ENTRY(setjmp)
60	movq	%rbx, 0(%rdi)
61	movq	%r12, 8(%rdi)
62	movq	%r13, 16(%rdi)
63	movq	%r14, 24(%rdi)
64	movq	%r15, 32(%rdi)
65	movq	%rbp, 40(%rdi)
66	popq	%rdx		/* return address */
67	movq	%rsp, 48(%rdi)
68	movq	%rdx, 56(%rdi)
69	xorl	%eax, %eax	/* return 0 */
70	jmp	*%rdx
71	SET_SIZE(setjmp)
72
73	ENTRY(longjmp)
74	movq	0(%rdi), %rbx
75	movq	8(%rdi), %r12
76	movq	16(%rdi), %r13
77	movq	24(%rdi), %r14
78	movq	32(%rdi), %r15
79	movq	40(%rdi), %rbp
80	movq	48(%rdi), %rsp
81	movl	%esi, %eax
82	test	%eax, %eax	/* if val != 0		*/
83	jnz	1f		/* 	return val	*/
84	incl	%eax		/* else return 1	*/
851:
86	movq	56(%rdi), %rdx	/* return to caller of setjmp */
87	jmp	*%rdx
88	SET_SIZE(longjmp)
89