Rajalakshmi Srinivasaraghavan b42f8cad52 powerpc: strstr optimization
This patch optimizes strstr function for power >= 7 systems.  Performance
gain is obtained using aligned memory access and usage of cmpb
instruction for quicker comparison.  The average improvement of this
optimization is ~40%.  Tested on ppc64 and ppc64le.

2015-07-16  Rajalakshmi Srinivasaraghavan  <raji@linux.vnet.ibm.com>

	* sysdeps/powerpc/powerpc64/multiarch/Makefile: Add strstr().
	* sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c: Likewise.
	* sysdeps/powerpc/powerpc64/power7/strstr.S: New File.
	* sysdeps/powerpc/powerpc64/multiarch/strstr-power7.S: New File.
	* sysdeps/powerpc/powerpc64/multiarch/strstr-ppc64.c: New File.
	* sysdeps/powerpc/powerpc64/multiarch/strstr.c: New File.
2015-07-16 13:43:51 -03:00

35 lines
1.3 KiB
C

/* Multiple versions of strstr. PowerPC64 version.
Copyright (C) 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/>. */
/* Define multiple versions only for definition in libc. */
#if IS_IN (libc)
# include <string.h>
# include <shlib-compat.h>
# include "init-arch.h"
extern __typeof (strstr) __strstr_ppc attribute_hidden;
extern __typeof (strstr) __strstr_power7 attribute_hidden;
/* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
ifunc symbol properly. */
libc_ifunc (strstr,
(hwcap & PPC_FEATURE_HAS_VSX)
? __strstr_power7
: __strstr_ppc);
#endif