glibc/sysdeps/unix/sysv/linux/arm/eabi/sigrestorer.S
Daniel Jacobowitz 99e5e16c5c * sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_SIGFRAME_V2): Define for 2.6.18 and later.
	* sysdeps/unix/sysv/linux/arm/eabi/sigrestorer.S
	(__default_sa_restorer): Rename to __default_sa_restorer_v1.
	Don't define if __ASSUME_SIGFRAME_V2.
	(__default_rt_sa_restorer): Rename to
	__default_rt_sa_restorer_v1.  Don't define if
	__ASSUME_SIGFRAME_V2.
	(__default_sa_restorer_v2, __default_rt_sa_restorer_v2): New.
	* sysdeps/unix/sysv/linux/arm/nptl/Versions
	(__default_sa_restorer_v1, __default_rt_sa_restorer_v1,
	__default_sa_restorer_v2, __default_rt_sa_restorer_v2): Add to
	GLIBC_PRIVATE.
	* sysdeps/unix/sysv/linux/arm/sigaction.c [__ARM_EABI__]
	(__default_sa_restorer_v1, __default_sa_restorer_v2,
	__default_rt_sa_restorer_v1, __default_rt_sa_restorer_v2):
	Declare.
	(__default_sa_restorer, __default_rt_sa_restorer): Define as
	macros depending on kernel version.
2007-05-23 17:33:17 +00:00

80 lines
2.2 KiB
ArmAsm

/* Copyright (C) 1999, 2005 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. */
#include <sysdep.h>
/* If no SA_RESTORER function was specified by the application we use
one of these. This avoids the need for the kernel to synthesise a return
instruction on the stack, which would involve expensive cache flushes.
Nowadays (2.6 series, and somewhat earlier) the kernel uses a high page
for signal trampolines, so the cache flushes are not an issue. But since
we do not have a vDSO, continue to use these so that we can provide
unwind information.
Start the unwind tables at least one instruction before the signal
trampoline, because the unwinder will assume we are returning after
a call site.
Because the signal frame layout changed in 2.6.18, we provide two
copies of these functions with different unwind information. */
#ifndef __ASSUME_SIGFRAME_V2
.fnstart
.save {r0-r15}
.pad #12
nop
ENTRY(__default_sa_restorer_v1)
mov r7, $SYS_ify(sigreturn)
swi 0x0
.fnend
#endif
.fnstart
.save {r0-r15}
.pad #32
nop
ENTRY(__default_sa_restorer_v2)
mov r7, $SYS_ify(sigreturn)
swi 0x0
.fnend
#ifdef __NR_rt_sigreturn
#ifndef __ASSUME_SIGFRAME_V2
.fnstart
.save {r0-r15}
.pad #168
nop
ENTRY(__default_rt_sa_restorer_v1)
mov r7, $SYS_ify(rt_sigreturn)
swi 0x0
.fnend
#endif
.fnstart
.save {r0-r15}
.pad #160
nop
ENTRY(__default_rt_sa_restorer_v2)
mov r7, $SYS_ify(rt_sigreturn)
swi 0x0
.fnend
#endif