Detect if AVX2 is usable

This patch checks and sets bit_AVX2_Usable in __cpu_features.feature.

	* sysdeps/x86_64/multiarch/ifunc-defines.sym (COMMON_CPUID_INDEX_7):
	New.
	* sysdeps/x86_64/multiarch/init-arch.c (__init_cpu_features):
	Check and set bit_AVX2_Usable.
	* sysdeps/x86_64/multiarch/init-arch.h (bit_AVX2_Usable): New
	macro.
	(bit_AVX2): Likewise.
	(index_AVX2_Usable): Likewise.
	(CPUID_AVX2): Likewise.
	(HAS_AVX2): Likewise.

diff --git a/ChangeLog b/ChangeLog
index 7267472..97ddfa7 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2014-04-17  Sihai Yao  <sihai.ysh@alibaba-inc.com>
+
+       * sysdeps/x86_64/multiarch/ifunc-defines.sym (COMMON_CPUID_INDEX_7):
+       New.
+       * sysdeps/x86_64/multiarch/init-arch.c (__init_cpu_features):
+       Check and set bit_AVX2_Usable.
+       * sysdeps/x86_64/multiarch/init-arch.h (bit_AVX2_Usable): New
+       macro.
+       (bit_AVX2): Likewise.
+       (index_AVX2_Usable): Likewise.
+       (CPUID_AVX2): Likewise.
+       (HAS_AVX2): Likewise.
+
 2014-04-17  Will Newton  <will.newton@linaro.org>
 
        * manual/setjmp.texi (System V contexts): Add note that

diff --git a/sysdeps/x86_64/multiarch/ifunc-defines.sym b/sysdeps/x86_64/multiarch/ifunc-defines.sym
index eb1538a..a410d88 100644 (file)
--- a/sysdeps/x86_64/multiarch/ifunc-defines.sym
+++ b/sysdeps/x86_64/multiarch/ifunc-defines.sym
@@ -17,4 +17,5 @@ FEATURE_OFFSET                offsetof (struct cpu_features, feature)
 FEATURE_SIZE           sizeof (unsigned int)
 
 COMMON_CPUID_INDEX_1
+COMMON_CPUID_INDEX_7
 FEATURE_INDEX_1

diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/init-arch.c
index db74d97..2a6dcb7 100644 (file)
--- a/sysdeps/x86_64/multiarch/init-arch.c
+++ b/sysdeps/x86_64/multiarch/init-arch.c
@@ -167,6 +167,9 @@ __init_cpu_features (void)
          /* Determine if AVX is usable.  */
          if (CPUID_AVX)
            __cpu_features.feature[index_AVX_Usable] |= bit_AVX_Usable;
+         /* Determine if AVX2 is usable.  */
+         if (CPUID_AVX2)
+           __cpu_features.feature[index_AVX2_Usable] |= bit_AVX2_Usable;
          /* Determine if FMA is usable.  */
          if (CPUID_FMA)
            __cpu_features.feature[index_FMA_Usable] |= bit_FMA_Usable;

diff --git a/sysdeps/x86_64/multiarch/init-arch.h b/sysdeps/x86_64/multiarch/init-arch.h
index 793707a..813b6de 100644 (file)
--- a/sysdeps/x86_64/multiarch/init-arch.h
+++ b/sysdeps/x86_64/multiarch/init-arch.h
@@ -24,6 +24,7 @@
 #define bit_FMA_Usable                 (1 << 7)
 #define bit_FMA4_Usable                        (1 << 8)
 #define bit_Slow_SSE4_2                        (1 << 9)
+#define bit_AVX2_Usable                        (1 << 10)
 
 /* CPUID Feature flags.  */
 
@@ -40,6 +41,7 @@
 
 /* COMMON_CPUID_INDEX_7.  */
 #define bit_RTM                (1 << 11)
+#define bit_AVX2       (1 << 5)
 
 /* XCR0 Feature flags.  */
 #define bit_XMM_state  (1 << 1)
@@ -54,6 +56,7 @@
 # define index_SSE4_1  COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
 # define index_SSE4_2  COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
 # define index_AVX     COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
+# define index_AVX2    COMMON_CPUID_INDEX_7*CPUID_SIZE+CPUID_EBX_OFFSET
 
 # define index_Fast_Rep_String         FEATURE_INDEX_1*FEATURE_SIZE
 # define index_Fast_Copy_Backward      FEATURE_INDEX_1*FEATURE_SIZE
@@ -64,6 +67,7 @@
 # define index_FMA_Usable              FEATURE_INDEX_1*FEATURE_SIZE
 # 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
 
 #else  /* __ASSEMBLER__ */
 
@@ -145,6 +149,8 @@ extern const struct cpu_features *__get_cpu_features (void)
   HAS_CPUID_FLAG (COMMON_CPUID_INDEX_80000001, ecx, bit_FMA4)
 # define CPUID_RTM \
   HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_RTM)
+# define CPUID_AVX2 \
+  HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_AVX2)
 
 /* HAS_* evaluates to true if we may use the feature at runtime.  */
 # define HAS_SSE2      HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, edx, bit_SSE2)
@@ -153,6 +159,7 @@ extern const struct cpu_features *__get_cpu_features (void)
 # define HAS_SSE4_1    HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_SSE4_1)
 # define HAS_SSE4_2    HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_SSE4_2)
 # define HAS_RTM       HAS_CPU_FEATURE (COMMON_CPUID_INDEX_7, ebx, bit_RTM)
+# define HAS_AVX2      HAS_CPU_FEATURE (COMMON_CPUID_INDEX_7, ebx, bit_AVX2)
 
 # define index_Fast_Rep_String         FEATURE_INDEX_1
 # define index_Fast_Copy_Backward      FEATURE_INDEX_1
@@ -163,6 +170,7 @@ extern const struct cpu_features *__get_cpu_features (void)
 # define index_FMA_Usable              FEATURE_INDEX_1
 # define index_FMA4_Usable             FEATURE_INDEX_1
 # define index_Slow_SSE4_2             FEATURE_INDEX_1
+# define index_AVX2_Usable             FEATURE_INDEX_1
 
 # define HAS_ARCH_FEATURE(name) \
   ((__get_cpu_features ()->feature[index_##name] & (bit_##name)) != 0)