summaryrefslogtreecommitdiff
path: root/sysdeps/i386/bsd-setjmp.S
blob: c9af0e14777af1f4ab65762a72998c7f0bdc011a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
/* BSD `setjmp' entry point to `sigsetjmp (..., 1)'.  i386 version.
   Copyright (C) 1994-1997,2000,2001,2005, 2006 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* This just does a tail-call to `__sigsetjmp (ARG, 1)'.
   We cannot do it in C because it must be a tail-call, so frame-unwinding
   in setjmp doesn't clobber the state restored by longjmp.  */

#include <sysdep.h>
#include <jmpbuf-offsets.h>
#include "bp-sym.h"
#include "bp-asm.h"

#define PARMS  LINKAGE		/* no space for saved regs */
#define JMPBUF PARMS
#define SIGMSK JMPBUF+PTR_SIZE

ENTRY (BP_SYM (setjmp))
	/* Note that we have to use a non-exported symbol in the next
	   jump since otherwise gas will emit it as a jump through the
	   PLT which is what we cannot use here.  */
	ENTER

	movl JMPBUF(%esp), %eax
	CHECK_BOUNDS_BOTH_WIDE (%eax, JMPBUF(%esp), $JB_SIZE)

     	/* Save registers.  */
	movl %ebx, (JB_BX*4)(%eax)
	movl %esi, (JB_SI*4)(%eax)
	movl %edi, (JB_DI*4)(%eax)
	leal JMPBUF(%esp), %ecx	/* Save SP as it will be after we return.  */
#ifdef PTR_MANGLE
	PTR_MANGLE (%ecx)
#endif
     	movl %ecx, (JB_SP*4)(%eax)
	movl PCOFF(%esp), %ecx	/* Save PC we are returning to now.  */
#ifdef PTR_MANGLE
	PTR_MANGLE (%ecx)
#endif
     	movl %ecx, (JB_PC*4)(%eax)
	LEAVE /* pop frame pointer to prepare for tail-call.  */
	movl %ebp, (JB_BP*4)(%eax) /* Save caller's frame pointer.  */

	/* Call __sigjmp_save.  */
	pushl $1
	cfi_adjust_cfa_offset (4)
	pushl 8(%esp)
	cfi_adjust_cfa_offset (4)
	call BP_SYM (__sigjmp_save)
	popl %ecx
	cfi_adjust_cfa_offset (-4)
	popl %edx
	cfi_adjust_cfa_offset (-4)
	ret
END (BP_SYM (setjmp))