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| author | H.J. Lu <hjl.tools@gmail.com> | 2016-04-01 15:08:48 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2016-04-01 15:09:14 -0700 |
| commit | 27d3ce1467990f89126e228559dec8f84b96c60e (patch) | |
| tree | 2d67df078f6e7ad4fdb0f7492426922ff762b9ee | |
| parent | 2e51bc3813ca3fe72fd197d08d79496e46669f43 (diff) | |
| download | glibc-27d3ce1467990f89126e228559dec8f84b96c60e.tar.gz glibc-27d3ce1467990f89126e228559dec8f84b96c60e.tar.xz glibc-27d3ce1467990f89126e228559dec8f84b96c60e.zip | |
Remove Fast_Copy_Backward from Intel Core processors
Intel Core i3, i5 and i7 processors have fast unaligned copy and copy backward is ignored. Remove Fast_Copy_Backward from Intel Core processors to avoid confusion. * sysdeps/x86/cpu-features.c (init_cpu_features): Don't set bit_arch_Fast_Copy_Backward for Intel Core proessors.
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | sysdeps/x86/cpu-features.c | 6 |
2 files changed, 6 insertions, 5 deletions
diff --git a/ChangeLog b/ChangeLog index c181042349..d22231b95d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2016-04-01 H.J. Lu <hongjiu.lu@intel.com> + + * sysdeps/x86/cpu-features.c (init_cpu_features): Don't set + bit_arch_Fast_Copy_Backward for Intel Core proessors. + 2016-04-01 Adhemerval Zanella <adhemerval.zanella@linaro.org> * string/strcspn.c (strcspn): Use PTR_ALIGN_DOWN. diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c index de75c79cf9..963b845916 100644 --- a/sysdeps/x86/cpu-features.c +++ b/sysdeps/x86/cpu-features.c @@ -176,11 +176,8 @@ init_cpu_features (struct cpu_features *cpu_features) case 0x2c: case 0x2e: case 0x2f: - /* Rep string instructions, copy backward, unaligned loads + /* Rep string instructions, unaligned load, unaligned copy, and pminub are fast on Intel Core i3, i5 and i7. */ -#if index_arch_Fast_Rep_String != index_arch_Fast_Copy_Backward -# error index_arch_Fast_Rep_String != index_arch_Fast_Copy_Backward -#endif #if index_arch_Fast_Rep_String != index_arch_Fast_Unaligned_Load # error index_arch_Fast_Rep_String != index_arch_Fast_Unaligned_Load #endif @@ -192,7 +189,6 @@ init_cpu_features (struct cpu_features *cpu_features) #endif cpu_features->feature[index_arch_Fast_Rep_String] |= (bit_arch_Fast_Rep_String - | bit_arch_Fast_Copy_Backward | bit_arch_Fast_Unaligned_Load | bit_arch_Fast_Unaligned_Copy | bit_arch_Prefer_PMINUB_for_stringop); |