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authorH.J. Lu <hjl.tools@gmail.com>2016-06-07 08:00:21 -0700
committerH.J. Lu <hjl.tools@gmail.com>2016-06-07 08:00:40 -0700
commit91655fc307fec2d5a8d60446b4de11cc986b47fa (patch)
tree0c0cf306a4134b0414792b6e26f0c4e24cd76117 /sysdeps/x86
parentc9bd40daaee18cf1d9824e4a7ebaebe321e0a5a8 (diff)
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Check FMA after COMMON_CPUID_INDEX_80000001
Since the FMA4 bit is in COMMON_CPUID_INDEX_80000001 and FMA4 requires
AVX, determine if FMA4 is usable after COMMON_CPUID_INDEX_80000001 is
available and if AVX is usable.

	[BZ #20195]
	* sysdeps/x86/cpu-features.c (get_common_indeces): Move FMA4
	check to ...
	(init_cpu_features): Here.
Diffstat (limited to 'sysdeps/x86')
-rw-r--r--sysdeps/x86/cpu-features.c13
1 files changed, 9 insertions, 4 deletions
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index a5fa81f709..9ce4b495a5 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -87,10 +87,6 @@ get_common_indeces (struct cpu_features *cpu_features,
 	  if (CPU_FEATURES_CPU_P (cpu_features, FMA))
 	    cpu_features->feature[index_arch_FMA_Usable]
 	      |= bit_arch_FMA_Usable;
-	  /* Determine if FMA4 is usable.  */
-	  if (CPU_FEATURES_CPU_P (cpu_features, FMA4))
-	    cpu_features->feature[index_arch_FMA4_Usable]
-	      |= bit_arch_FMA4_Usable;
 	}
     }
 }
@@ -230,6 +226,15 @@ init_cpu_features (struct cpu_features *cpu_features)
 		 cpu_features->cpuid[COMMON_CPUID_INDEX_80000001].ecx,
 		 cpu_features->cpuid[COMMON_CPUID_INDEX_80000001].edx);
 
+      if (HAS_ARCH_FEATURE (AVX_Usable))
+	{
+	  /* Since the FMA4 bit is in COMMON_CPUID_INDEX_80000001 and
+	     FMA4 requires AVX, determine if FMA4 is usable here.  */
+	  if (CPU_FEATURES_CPU_P (cpu_features, FMA4))
+	    cpu_features->feature[index_arch_FMA4_Usable]
+	      |= bit_arch_FMA4_Usable;
+	}
+
       if (family == 0x15)
 	{
 #if index_arch_Fast_Unaligned_Load != index_arch_Fast_Copy_Backward