Blame sysdeps/i386/bsd-_setjmp.S

Packit 6c4009
/* BSD `_setjmp' entry point to `sigsetjmp (..., 0)'.  i386 version.
Packit 6c4009
   Copyright (C) 1994-2018 Free Software Foundation, Inc.
Packit 6c4009
   This file is part of the GNU C Library.
Packit 6c4009
Packit 6c4009
   The GNU C Library is free software; you can redistribute it and/or
Packit 6c4009
   modify it under the terms of the GNU Lesser General Public
Packit 6c4009
   License as published by the Free Software Foundation; either
Packit 6c4009
   version 2.1 of the License, or (at your option) any later version.
Packit 6c4009
Packit 6c4009
   The GNU C Library is distributed in the hope that it will be useful,
Packit 6c4009
   but WITHOUT ANY WARRANTY; without even the implied warranty of
Packit 6c4009
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Packit 6c4009
   Lesser General Public License for more details.
Packit 6c4009
Packit 6c4009
   You should have received a copy of the GNU Lesser General Public
Packit 6c4009
   License along with the GNU C Library; if not, see
Packit 6c4009
   <http://www.gnu.org/licenses/>.  */
Packit 6c4009
Packit 6c4009
/* This just does a tail-call to `__sigsetjmp (ARG, 0)'.
Packit 6c4009
   We cannot do it in C because it must be a tail-call, so frame-unwinding
Packit 6c4009
   in setjmp doesn't clobber the state restored by longjmp.  */
Packit 6c4009
Packit 6c4009
#include <sysdep.h>
Packit 6c4009
#include <jmpbuf-offsets.h>
Packit 6c4009
#include <jmp_buf-ssp.h>
Packit 6c4009
#include <stap-probe.h>
Packit 6c4009
Packit 6c4009
#define PARMS	4		/* no space for saved regs */
Packit 6c4009
#define JMPBUF	PARMS
Packit 6c4009
#define SIGMSK	JMPBUF+4
Packit 6c4009
Packit 6c4009
/* Don't save shadow stack register if shadow stack isn't enabled.  */
Packit 6c4009
#if !SHSTK_ENABLED
Packit 6c4009
# undef SHADOW_STACK_POINTER_OFFSET
Packit 6c4009
#endif
Packit 6c4009
Packit 6c4009
ENTRY (_setjmp)
Packit 6c4009
Packit 6c4009
	xorl %eax, %eax
Packit 6c4009
	movl JMPBUF(%esp), %edx
Packit 6c4009
Packit 6c4009
	/* Save registers.  */
Packit 6c4009
	movl %ebx, (JB_BX*4)(%edx)
Packit 6c4009
	movl %esi, (JB_SI*4)(%edx)
Packit 6c4009
	movl %edi, (JB_DI*4)(%edx)
Packit 6c4009
	leal JMPBUF(%esp), %ecx	/* Save SP as it will be after we return.  */
Packit 6c4009
#ifdef PTR_MANGLE
Packit 6c4009
	PTR_MANGLE (%ecx)
Packit 6c4009
#endif
Packit 6c4009
	movl %ecx, (JB_SP*4)(%edx)
Packit 6c4009
	movl 0(%esp), %ecx	/* Save PC we are returning to now.  */
Packit 6c4009
	LIBC_PROBE (setjmp, 3, 4@%edx, -4@$0, 4@%ecx)
Packit 6c4009
#ifdef PTR_MANGLE
Packit 6c4009
	PTR_MANGLE (%ecx)
Packit 6c4009
#endif
Packit 6c4009
	movl %ecx, (JB_PC*4)(%edx)
Packit 6c4009
	movl %ebp, (JB_BP*4)(%edx) /* Save caller's frame pointer.  */
Packit 6c4009
Packit 6c4009
	movl %eax, JB_SIZE(%edx) /* No signal mask set.  */
Packit 6c4009
#ifdef SHADOW_STACK_POINTER_OFFSET
Packit 6c4009
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
Packit 6c4009
	/* Check if Shadow Stack is enabled.  */
Packit 6c4009
	testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
Packit 6c4009
	jz L(skip_ssp)
Packit 6c4009
# else
Packit 6c4009
	xorl %ecx, %ecx
Packit 6c4009
# endif
Packit 6c4009
	/* Get the current Shadow-Stack-Pointer and save it.  */
Packit 6c4009
	rdsspd %ecx
Packit 6c4009
	movl %ecx, SHADOW_STACK_POINTER_OFFSET(%edx)
Packit 6c4009
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
Packit 6c4009
L(skip_ssp):
Packit 6c4009
# endif
Packit 6c4009
#endif
Packit 6c4009
	ret
Packit 6c4009
END (_setjmp)
Packit 6c4009
libc_hidden_def (_setjmp)