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| author | H.J. Lu <hjl.tools@gmail.com> | 2015-01-30 06:50:20 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2015-01-30 15:37:58 -0800 |
| commit | 5f3d0b78e011d2a72f9e88b0e9ef5bc081d18f97 (patch) | |
| tree | 8eabf127206283d2421bc40b6bc44e123e346598 /sysdeps/x86_64/multiarch/init-arch.h | |
| parent | b658fdd82b4524cf6a39881d092caa23f63d93ac (diff) | |
| download | glibc-5f3d0b78e011d2a72f9e88b0e9ef5bc081d18f97.tar.gz glibc-5f3d0b78e011d2a72f9e88b0e9ef5bc081d18f97.tar.xz glibc-5f3d0b78e011d2a72f9e88b0e9ef5bc081d18f97.zip | |
Use AVX unaligned memcpy only if AVX2 is available
memcpy with unaligned 256-bit AVX register loads/stores are slow on older processorsl like Sandy Bridge. This patch adds bit_AVX_Fast_Unaligned_Load and sets it only when AVX2 is available. [BZ #17801] * sysdeps/x86_64/multiarch/init-arch.c (__init_cpu_features): Set the bit_AVX_Fast_Unaligned_Load bit for AVX2. * sysdeps/x86_64/multiarch/init-arch.h (bit_AVX_Fast_Unaligned_Load): New. (index_AVX_Fast_Unaligned_Load): Likewise. (HAS_AVX_FAST_UNALIGNED_LOAD): Likewise. * sysdeps/x86_64/multiarch/memcpy.S (__new_memcpy): Check the bit_AVX_Fast_Unaligned_Load bit instead of the bit_AVX_Usable bit. * sysdeps/x86_64/multiarch/memcpy_chk.S (__memcpy_chk): Likewise. * sysdeps/x86_64/multiarch/mempcpy.S (__mempcpy): Likewise. * sysdeps/x86_64/multiarch/mempcpy_chk.S (__mempcpy_chk): Likewise. * sysdeps/x86_64/multiarch/memmove.c (__libc_memmove): Replace HAS_AVX with HAS_AVX_FAST_UNALIGNED_LOAD. * sysdeps/x86_64/multiarch/memmove_chk.c (__memmove_chk): Likewise.
Diffstat (limited to 'sysdeps/x86_64/multiarch/init-arch.h')
| -rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/init-arch.h b/sysdeps/x86_64/multiarch/init-arch.h index 55f1c5b34c..e6b5ba5530 100644 --- a/sysdeps/x86_64/multiarch/init-arch.h +++ b/sysdeps/x86_64/multiarch/init-arch.h @@ -25,6 +25,7 @@ #define bit_FMA4_Usable (1 << 8) #define bit_Slow_SSE4_2 (1 << 9) #define bit_AVX2_Usable (1 << 10) +#define bit_AVX_Fast_Unaligned_Load (1 << 11) /* CPUID Feature flags. */ @@ -74,6 +75,7 @@ # define index_FMA4_Usable FEATURE_INDEX_1*FEATURE_SIZE # define index_Slow_SSE4_2 FEATURE_INDEX_1*FEATURE_SIZE # define index_AVX2_Usable FEATURE_INDEX_1*FEATURE_SIZE +# define index_AVX_Fast_Unaligned_Load FEATURE_INDEX_1*FEATURE_SIZE #else /* __ASSEMBLER__ */ @@ -169,6 +171,7 @@ extern const struct cpu_features *__get_cpu_features (void) # define index_FMA4_Usable FEATURE_INDEX_1 # define index_Slow_SSE4_2 FEATURE_INDEX_1 # define index_AVX2_Usable FEATURE_INDEX_1 +# define index_AVX_Fast_Unaligned_Load FEATURE_INDEX_1 # define HAS_ARCH_FEATURE(name) \ ((__get_cpu_features ()->feature[index_##name] & (bit_##name)) != 0) @@ -181,5 +184,6 @@ extern const struct cpu_features *__get_cpu_features (void) # define HAS_AVX2 HAS_ARCH_FEATURE (AVX2_Usable) # define HAS_FMA HAS_ARCH_FEATURE (FMA_Usable) # define HAS_FMA4 HAS_ARCH_FEATURE (FMA4_Usable) +# define HAS_AVX_FAST_UNALIGNED_LOAD HAS_ARCH_FEATURE (AVX_Fast_Unaligned_Load) #endif /* __ASSEMBLER__ */ |