diff options
author | Vidya Ranganathan <vidya@linux.vnet.ibm.com> | 2014-05-05 19:10:45 -0500 |
---|---|---|
committer | Adhemerval Zanella <azanella@linux.vnet.ibm.com> | 2014-05-06 09:54:25 -0500 |
commit | f360f94a05570045be615649e9a411cefba2e210 (patch) | |
tree | ac6fb86d01ea80b3bf914c2f74aa231b42bfda28 /sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S | |
parent | 978a41c35738dbe4592edb7dcaa155fec31dab50 (diff) | |
download | glibc-f360f94a05570045be615649e9a411cefba2e210.zip glibc-f360f94a05570045be615649e9a411cefba2e210.tar.gz glibc-f360f94a05570045be615649e9a411cefba2e210.tar.bz2 |
PowerPC: strncpy/stpncpy optimization for PPC64/POWER7
The optimization is achieved by following techniques:
> data alignment [gain from aligned memory access on read/write]
> POWER7 gains performance with loop unrolling/unwinding
[gain by reduction of branch penalty].
> zero padding done by calling optimized memset
Diffstat (limited to 'sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S')
-rw-r--r-- | sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S b/sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S new file mode 100644 index 0000000..e29674f --- /dev/null +++ b/sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S @@ -0,0 +1,44 @@ +/* Optimized stpncpy implementation for POWER7. + Copyright (C) 2014 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> + +#define USE_AS_STPNCPY + +#undef EALIGN +#define EALIGN(name, alignt, words) \ + .section ".text"; \ + ENTRY_2(__stpncpy_power7) \ + .align ALIGNARG(alignt); \ + EALIGN_W_##words; \ + BODY_LABEL(__stpncpy_power7): \ + cfi_startproc; \ + LOCALENTRY(__stpncpy_power7) + +#undef END +#define END(name) \ + cfi_endproc; \ + TRACEBACK(__stpncpy_power7) \ + END_2(__stpncpy_power7) + +#undef libc_hidden_builtin_def +#define libc_hidden_builtin_def(name) + +#define MEMSET __memset_power7 + +#include <sysdeps/powerpc/powerpc64/power7/stpncpy.S> |