glibc/sysdeps/unix/sysv/linux/powerpc/syscall.S
Paul E. Murphy 18173559a2 powerpc: Fix tabort usage in syscalls
Fix usage of tabort in generated syscalls.  r0 has special meaning
when used with this instruction, thus it will not generate
persistent errors, nor return an error code.  This mitigates poor
CPU usage when performing elided critical sections.

Additionally, transactions should be aborted when entering a user
invoked syscall.  Otherwise the results of the transaction may be
undefined.

2015-08-25  Paul E. Murphy  <murphyp@linux.vnet.ibm.com>

	* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION): Use
	register other than r0 for tabort, it has special meaning.
	* sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION): Likewise
	* sysdeps/unix.sysv/linux/powerpc/syscall.S (syscall): Abort
	transaction before starting syscall.
2015-08-25 13:45:56 -03:00

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ArmAsm

/* Copyright (C) 1991-2015 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, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
ENTRY (syscall)
ABORT_TRANSACTION
mr r0,r3
mr r3,r4
mr r4,r5
mr r5,r6
mr r6,r7
mr r7,r8
mr r8,r9
sc
PSEUDO_RET
PSEUDO_END (syscall)