diff options
| author | H.J. Lu <hongjiu.lu@intel.com> | 2010-04-14 00:12:53 -0700 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2010-04-14 00:12:53 -0700 |
| commit | 404a6e32012cfef041709639e13d200ae0b2c0c6 (patch) | |
| tree | 4ffa43d5620d96bd7cc791ad037b92fa9afb218a /sysdeps/x86_64/multiarch/memcmp.S | |
| parent | bbbdd7780916358c65e8bc98c989126a7db2f43e (diff) | |
| download | glibc-404a6e32012cfef041709639e13d200ae0b2c0c6.tar.gz glibc-404a6e32012cfef041709639e13d200ae0b2c0c6.tar.xz glibc-404a6e32012cfef041709639e13d200ae0b2c0c6.zip | |
x86-64 SSE4 optimized memcmp
This is 64bit SSE4 optimized memcmp. It improves memcmp by upto 3X on Intel Core i7.
Diffstat (limited to 'sysdeps/x86_64/multiarch/memcmp.S')
| -rw-r--r-- | sysdeps/x86_64/multiarch/memcmp.S | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/memcmp.S b/sysdeps/x86_64/multiarch/memcmp.S new file mode 100644 index 0000000000..301ab287f5 --- /dev/null +++ b/sysdeps/x86_64/multiarch/memcmp.S @@ -0,0 +1,59 @@ +/* Multiple versions of memcmp + Copyright (C) 2010 Free Software Foundation, Inc. + Contributed by Intel Corporation. + 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> +#include <init-arch.h> + +/* Define multiple versions only for the definition in libc. */ +#ifndef NOT_IN_libc + .text +ENTRY(memcmp) + .type memcmp, @gnu_indirect_function + cmpl $0, KIND_OFFSET+__cpu_features(%rip) + jne 1f + call __init_cpu_features +1: leaq __memcmp_sse2(%rip), %rax + testl $bit_SSE4_1, __cpu_features+CPUID_OFFSET+index_SSE4_1(%rip) + jz 2f + leaq __memcmp_sse4_1(%rip), %rax +2: ret +END(memcmp) + +# undef ENTRY +# define ENTRY(name) \ + .type __memcmp_sse2, @function; \ + .p2align 4; \ + __memcmp_sse2: cfi_startproc; \ + CALL_MCOUNT +# undef END +# define END(name) \ + cfi_endproc; .size __memcmp_sse2, .-__memcmp_sse2 + +# ifdef SHARED +# undef libc_hidden_builtin_def +/* IFUNC doesn't work with the hidden functions in shared library since + they will be called without setting up EBX needed for PLT which is + used by IFUNC. */ +# define libc_hidden_builtin_def(name) \ + .globl __GI_memcmp; __GI_memcmp = __memcmp_sse2 +# endif +#endif + +#include "../memcmp.S" |