Set index_Fast_Unaligned_Load for Excavator family CPUs

GLIBC benchtest testcases shows SSE2_Unaligned based implementations are performing faster compare to SSE2 based implementations for routines: strcmp, strcat, strncat, stpcpy, stpncpy, strcpy, strncpy and strstr. Flag index_Fast_Unaligned_Load is set for Excavator family 0x15h CPU's. This makes SSE2_Unaligned based implementations as default for these routines. [BZ #19467] * sysdeps/x86/cpu-features.c (init_cpu_features): Set index_Fast_Unaligned_Load flag for Excavator family CPUs.
git-mirror · Jan 14, 2016 · d7890e6 · d7890e6
1 parent a4b5177
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diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,9 @@
+2016-01-14  Amit Pawar  <amit.pawar@amd.com>
+
+	[BZ #19467]
+	* sysdeps/x86/cpu-features.c (init_cpu_features): Set
+	index_Fast_Unaligned_Load flag for Excavator family CPUs.
+
 2016-01-02  Marcin Kościelnicki  <koriakin@0x04.net>
 
 	* sysdeps/s390/nptl/tls.h (struct tcbhead_t): Add __private_ss field.

diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
@@ -154,6 +154,14 @@ init_cpu_features (struct cpu_features *cpu_features)
 		 cpu_features->cpuid[COMMON_CPUID_INDEX_80000001].ebx,
 		 cpu_features->cpuid[COMMON_CPUID_INDEX_80000001].ecx,
 		 cpu_features->cpuid[COMMON_CPUID_INDEX_80000001].edx);
+
+      if (family == 0x15)
+	{
+	  /* "Excavator"   */
+	  if (model >= 0x60 && model <= 0x7f)
+	    cpu_features->feature[index_Fast_Unaligned_Load]
+	      |= bit_Fast_Unaligned_Load;
+	}
     }
   else
     kind = arch_kind_other;