xref: /freebsd/lib/libc/amd64/gen/setjmp.S (revision 4b9d605768acabc460aa6dcfe8a1f8db35b16794)
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <machine/asm.h>
34/*
35 * C library -- _setjmp, _longjmp
36 *
37 *	longjmp(a,v)
38 * will generate a "return(v)" from the last call to
39 *	setjmp(a)
40 * by restoring registers from the environment 'a'.
41 * The previous signal state is restored.
42 */
43
44#include "SYS.h"
45
46ENTRY(setjmp)
47	pushq	%rdi
48	movq	%rdi,%rcx
49	movq	$1,%rdi			/* SIG_BLOCK       */
50	movq	$0,%rsi			/* (sigset_t*)set  */
51	leaq	72(%rcx),%rdx		/* 9,10; (sigset_t*)oset */
52	/* stack is 16-byte aligned */
53	call	__libc_sigprocmask
54	popq	%rdi
55	movq	%rdi,%rcx
56	movq	0(%rsp),%rdx		/* return address */
57	movq	%rdx, 0(%rcx)		/* 0; return address */
58	movq	%rbx, 8(%rcx)		/* 1; rbx */
59	movq	%rsp,16(%rcx)		/* 2; rsp */
60	movq	%rbp,24(%rcx)		/* 3; rbp */
61	movq	%r12,32(%rcx)		/* 4; r12 */
62	movq	%r13,40(%rcx)		/* 5; r13 */
63	movq	%r14,48(%rcx)		/* 6; r14 */
64	movq	%r15,56(%rcx)		/* 7; r15 */
65	fnstcw	64(%rcx)		/* 8; fpu cw */
66	stmxcsr	68(%rcx)		/*    and mxcsr */
67	xorq	%rax,%rax
68	ret
69END(setjmp)
70
71	WEAK_REFERENCE(__longjmp, longjmp)
72ENTRY(__longjmp)
73	pushq	%rdi
74	pushq	%rsi
75	movq	%rdi,%rdx
76	movq	$3,%rdi			/* SIG_SETMASK     */
77	leaq	72(%rdx),%rsi		/* (sigset_t*)set  */
78	movq	$0,%rdx			/* (sigset_t*)oset */
79	subq	$0x8,%rsp		/* make the stack 16-byte aligned */
80	call	__libc_sigprocmask
81	addq	$0x8,%rsp
82	popq	%rsi
83	popq	%rdi			/* jmpbuf */
84	movq	%rdi,%rdx
85	/* Restore the mxcsr, but leave exception flags intact. */
86	stmxcsr	-4(%rsp)
87	movl	68(%rdx),%eax
88	andl	$0xffffffc0,%eax
89	movl	-4(%rsp),%edi
90	andl	$0x3f,%edi
91	xorl	%eax,%edi
92	movl	%edi,-4(%rsp)
93	ldmxcsr -4(%rsp)
94	movq	%rsi,%rax		/* retval */
95	movq	0(%rdx),%rcx
96	movq	8(%rdx),%rbx
97	movq	16(%rdx),%rsp
98	movq	24(%rdx),%rbp
99	movq	32(%rdx),%r12
100	movq	40(%rdx),%r13
101	movq	48(%rdx),%r14
102	movq	56(%rdx),%r15
103	fldcw	64(%rdx)
104	testq	%rax,%rax
105	jnz	1f
106	incq	%rax
1071:	movq	%rcx,0(%rsp)		/* return address */
108	ret
109END(__longjmp)
110
111	.section .note.GNU-stack,"",%progbits
112