diff options
Diffstat (limited to 'sysdeps/x86_64/multiarch/strncmp.c')
-rw-r--r-- | sysdeps/x86_64/multiarch/strncmp.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/strncmp.c b/sysdeps/x86_64/multiarch/strncmp.c new file mode 100644 index 0000000000..02b6d0b6f5 --- /dev/null +++ b/sysdeps/x86_64/multiarch/strncmp.c @@ -0,0 +1,60 @@ +/* Multiple versions of strncmp. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017-2018 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 the definition in libc. */ +#if IS_IN (libc) +# define strncmp __redirect_strncmp +# include <string.h> +# undef strncmp + +# define SYMBOL_NAME strncmp +# include <init-arch.h> + +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3) attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden; + +static inline void * +IFUNC_SELECTOR (void) +{ + const struct cpu_features* cpu_features = __get_cpu_features (); + + if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER) + && CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable) + && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load)) + return OPTIMIZE (avx2); + + if (CPU_FEATURES_CPU_P (cpu_features, SSE4_2) + && !CPU_FEATURES_ARCH_P (cpu_features, Slow_SSE4_2)) + return OPTIMIZE (sse42); + + if (CPU_FEATURES_CPU_P (cpu_features, SSSE3)) + return OPTIMIZE (ssse3); + + return OPTIMIZE (sse2); +} + +libc_ifunc_redirected (__redirect_strncmp, strncmp, IFUNC_SELECTOR ()); + +# ifdef SHARED +__hidden_ver1 (strncmp, __GI_strncmp, __redirect_strncmp) + __attribute__ ((visibility ("hidden"))); +# endif +#endif |