Re: [PATCH] [x86_64] Detection of availability of AVX512F and AVX512DQ ISAs

[Andrew Senkevich <andrew dot n dot senkevich at gmail dot com>]

> Please add/use bit_ZMM0_15_state and bit_ZMM16_31_state.
> This file is used by both 32-bit and 64-bit. Does it work for both
> 32-bit and 64-bit?

Yes, here is refactored patch.

ChangeLog

2015-05-27  Andrew Senkevich  <andrew.senkevich@intel.com>

        * sysdeps/x86_64/multiarch/init-arch.h (bit_AVX512F_Usable,
        bit_AVX512DQ_Usable, bit_Opmask_state, bit_ZMM0_15_state,
        bit_ZMM16_31_state): New macro.
        * sysdeps/x86_64/multiarch/init-arch.c (__init_cpu_features):
        Check and set bit_AVX512F_Usable, bit_AVX512DQ_Usable.

diff --git a/sysdeps/x86_64/multiarch/init-arch.c
b/sysdeps/x86_64/multiarch/init-arch.c
index 7dec218..aaad5fa 100644
--- a/sysdeps/x86_64/multiarch/init-arch.c
+++ b/sysdeps/x86_64/multiarch/init-arch.c
@@ -179,6 +179,23 @@ __init_cpu_features (void)
   if (CPUID_AVX2)
     __cpu_features.feature[index_AVX2_Usable]
       |= bit_AVX2_Usable | bit_AVX_Fast_Unaligned_Load;
+  /* Check if OPMASK state, upper 256-bit of ZMM0-ZMM15 and
+     ZMM16-ZMM31 state are enabled.  */
+  if ((xcrlow & (bit_Opmask_state | bit_ZMM0_15_state
+ | bit_ZMM16_31_state)) ==
+      (bit_Opmask_state | bit_ZMM0_15_state | bit_ZMM16_31_state))
+    {
+      /* Determine if AVX512F is usable.  */
+      if (CPUID_AVX512F)
+ {
+  __cpu_features.feature[index_AVX512F_Usable]
+    |= bit_AVX512F_Usable;
+  /* Determine if AVX512DQ is usable.  */
+  if (CPUID_AVX512DQ)
+    __cpu_features.feature[index_AVX512DQ_Usable]
+      |= bit_AVX512DQ_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 e6b5ba5..cfc6e70 100644
--- a/sysdeps/x86_64/multiarch/init-arch.h
+++ b/sysdeps/x86_64/multiarch/init-arch.h
@@ -26,6 +26,8 @@
 #define bit_Slow_SSE4_2 (1 << 9)
 #define bit_AVX2_Usable (1 << 10)
 #define bit_AVX_Fast_Unaligned_Load (1 << 11)
+#define bit_AVX512F_Usable (1 << 12)
+#define bit_AVX512DQ_Usable (1 << 13)

 /* CPUID Feature flags.  */

@@ -43,10 +45,15 @@
 /* COMMON_CPUID_INDEX_7.  */
 #define bit_RTM (1 << 11)
 #define bit_AVX2 (1 << 5)
+#define bit_AVX512F (1 << 16)
+#define bit_AVX512DQ (1 << 17)

 /* XCR0 Feature flags.  */
 #define bit_XMM_state  (1 << 1)
 #define bit_YMM_state  (2 << 1)
+#define bit_Opmask_state (1 << 5)
+#define bit_ZMM0_15_state (1 << 6)
+#define bit_ZMM16_31_state (1 << 7)

 /* The integer bit array index for the first set of internal feature bits.  */
 # define FEATURE_INDEX_1 0
@@ -76,6 +83,8 @@
 # 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
+# define index_AVX512F_Usable FEATURE_INDEX_1*FEATURE_SIZE
+# define index_AVX512DQ_Usable FEATURE_INDEX_1*FEATURE_SIZE

 #else /* __ASSEMBLER__ */

@@ -152,6 +161,10 @@ extern const struct cpu_features *__get_cpu_features (void)
   HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_RTM)
 # define CPUID_AVX2 \
   HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_AVX2)
+# define CPUID_AVX512F \
+  HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_AVX512F)
+# define CPUID_AVX512DQ \
+  HAS_CPUID_FLAG (COMMON_CPUID_INDEX_7, ebx, bit_AVX512DQ)

 /* 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)
@@ -172,6 +185,8 @@ extern const struct cpu_features *__get_cpu_features (void)
 # 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 index_AVX512F_Usable FEATURE_INDEX_1
+# define index_AVX512DQ_Usable FEATURE_INDEX_1

 # define HAS_ARCH_FEATURE(name) \
   ((__get_cpu_features ()->feature[index_##name] & (bit_##name)) != 0)
@@ -182,6 +197,8 @@ extern const struct cpu_features *__get_cpu_features (void)
 # define HAS_FAST_UNALIGNED_LOAD HAS_ARCH_FEATURE (Fast_Unaligned_Load)
 # define HAS_AVX HAS_ARCH_FEATURE (AVX_Usable)
 # define HAS_AVX2 HAS_ARCH_FEATURE (AVX2_Usable)
+# define HAS_AVX512F HAS_ARCH_FEATURE (AVX512F_Usable)
+# define HAS_AVX512DQ HAS_ARCH_FEATURE (AVX512DQ_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)

Is it ok?


--
WBR,
Andrew