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authorH.J. Lu <hjl.tools@gmail.com>2016-03-22 07:46:56 -0700
committerH.J. Lu <hjl.tools@gmail.com>2016-03-22 07:47:20 -0700
commitf781a9e96138d8839663af5e88649ab1fbed74f8 (patch)
treefdb1a9b321a4cae52901cb88e52bff1f1a348a1a /sysdeps/x86
parentb87e41378beca3c98ec3464d64835e66cc788497 (diff)
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Set index_arch_AVX_Fast_Unaligned_Load only for Intel processors
Since only Intel processors with AVX2 have fast unaligned load, we should set index_arch_AVX_Fast_Unaligned_Load only for Intel processors. Move AVX, AVX2, AVX512, FMA and FMA4 detection into get_common_indeces and call get_common_indeces for other processors. Add CPU_FEATURES_CPU_P and CPU_FEATURES_ARCH_P to aoid loading GLRO(dl_x86_cpu_features) in cpu-features.c. [BZ #19583] * sysdeps/x86/cpu-features.c (get_common_indeces): Remove inline. Check family before setting family, model and extended_model. Set AVX, AVX2, AVX512, FMA and FMA4 usable bits here. (init_cpu_features): Replace HAS_CPU_FEATURE and HAS_ARCH_FEATURE with CPU_FEATURES_CPU_P and CPU_FEATURES_ARCH_P. Set index_arch_AVX_Fast_Unaligned_Load for Intel processors with usable AVX2. Call get_common_indeces for other processors with family == NULL. * sysdeps/x86/cpu-features.h (CPU_FEATURES_CPU_P): New macro. (CPU_FEATURES_ARCH_P): Likewise. (HAS_CPU_FEATURE): Use CPU_FEATURES_CPU_P. (HAS_ARCH_FEATURE): Use CPU_FEATURES_ARCH_P.
Diffstat (limited to 'sysdeps/x86')
-rw-r--r--sysdeps/x86/cpu-features.c152
-rw-r--r--sysdeps/x86/cpu-features.h10
2 files changed, 88 insertions, 74 deletions
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 1787716..c8f81ef 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -19,23 +19,79 @@
#include <cpuid.h>
#include <cpu-features.h>
-static inline void
+static void
get_common_indeces (struct cpu_features *cpu_features,
unsigned int *family, unsigned int *model,
unsigned int *extended_model)
{
- unsigned int eax;
- __cpuid (1, eax, cpu_features->cpuid[COMMON_CPUID_INDEX_1].ebx,
- cpu_features->cpuid[COMMON_CPUID_INDEX_1].ecx,
- cpu_features->cpuid[COMMON_CPUID_INDEX_1].edx);
- GLRO(dl_x86_cpu_features).cpuid[COMMON_CPUID_INDEX_1].eax = eax;
- *family = (eax >> 8) & 0x0f;
- *model = (eax >> 4) & 0x0f;
- *extended_model = (eax >> 12) & 0xf0;
- if (*family == 0x0f)
+ if (family)
{
- *family += (eax >> 20) & 0xff;
- *model += *extended_model;
+ unsigned int eax;
+ __cpuid (1, eax, cpu_features->cpuid[COMMON_CPUID_INDEX_1].ebx,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_1].ecx,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_1].edx);
+ cpu_features->cpuid[COMMON_CPUID_INDEX_1].eax = eax;
+ *family = (eax >> 8) & 0x0f;
+ *model = (eax >> 4) & 0x0f;
+ *extended_model = (eax >> 12) & 0xf0;
+ if (*family == 0x0f)
+ {
+ *family += (eax >> 20) & 0xff;
+ *model += *extended_model;
+ }
+ }
+
+ if (cpu_features->max_cpuid >= 7)
+ __cpuid_count (7, 0,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_7].eax,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_7].ebx,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_7].ecx,
+ cpu_features->cpuid[COMMON_CPUID_INDEX_7].edx);
+
+ /* Can we call xgetbv? */
+ if (CPU_FEATURES_CPU_P (cpu_features, OSXSAVE))
+ {
+ unsigned int xcrlow;
+ unsigned int xcrhigh;
+ asm ("xgetbv" : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0));
+ /* Is YMM and XMM state usable? */
+ if ((xcrlow & (bit_YMM_state | bit_XMM_state)) ==
+ (bit_YMM_state | bit_XMM_state))
+ {
+ /* Determine if AVX is usable. */
+ if (CPU_FEATURES_CPU_P (cpu_features, AVX))
+ cpu_features->feature[index_arch_AVX_Usable]
+ |= bit_arch_AVX_Usable;
+ /* Determine if AVX2 is usable. */
+ if (CPU_FEATURES_CPU_P (cpu_features, AVX2))
+ cpu_features->feature[index_arch_AVX2_Usable]
+ |= bit_arch_AVX2_Usable;
+ /* 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 (CPU_FEATURES_CPU_P (cpu_features, AVX512F))
+ {
+ cpu_features->feature[index_arch_AVX512F_Usable]
+ |= bit_arch_AVX512F_Usable;
+ /* Determine if AVX512DQ is usable. */
+ if (CPU_FEATURES_CPU_P (cpu_features, AVX512DQ))
+ cpu_features->feature[index_arch_AVX512DQ_Usable]
+ |= bit_arch_AVX512DQ_Usable;
+ }
+ }
+ /* Determine if FMA is usable. */
+ 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;
+ }
}
}
@@ -135,6 +191,12 @@ init_cpu_features (struct cpu_features *cpu_features)
break;
}
}
+
+ /* Unaligned load with 256-bit AVX registers are faster on
+ Intel processors with AVX2. */
+ if (CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable))
+ cpu_features->feature[index_arch_AVX_Fast_Unaligned_Load]
+ |= bit_arch_AVX_Fast_Unaligned_Load;
}
/* This spells out "AuthenticAMD". */
else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
@@ -165,73 +227,19 @@ init_cpu_features (struct cpu_features *cpu_features)
}
}
else
- kind = arch_kind_other;
+ {
+ kind = arch_kind_other;
+ get_common_indeces (cpu_features, NULL, NULL, NULL);
+ }
/* Support i586 if CX8 is available. */
- if (HAS_CPU_FEATURE (CX8))
+ if (CPU_FEATURES_CPU_P (cpu_features, CX8))
cpu_features->feature[index_arch_I586] |= bit_arch_I586;
/* Support i686 if CMOV is available. */
- if (HAS_CPU_FEATURE (CMOV))
+ if (CPU_FEATURES_CPU_P (cpu_features, CMOV))
cpu_features->feature[index_arch_I686] |= bit_arch_I686;
- if (cpu_features->max_cpuid >= 7)
- __cpuid_count (7, 0,
- cpu_features->cpuid[COMMON_CPUID_INDEX_7].eax,
- cpu_features->cpuid[COMMON_CPUID_INDEX_7].ebx,
- cpu_features->cpuid[COMMON_CPUID_INDEX_7].ecx,
- cpu_features->cpuid[COMMON_CPUID_INDEX_7].edx);
-
- /* Can we call xgetbv? */
- if (HAS_CPU_FEATURE (OSXSAVE))
- {
- unsigned int xcrlow;
- unsigned int xcrhigh;
- asm ("xgetbv" : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0));
- /* Is YMM and XMM state usable? */
- if ((xcrlow & (bit_YMM_state | bit_XMM_state)) ==
- (bit_YMM_state | bit_XMM_state))
- {
- /* Determine if AVX is usable. */
- if (HAS_CPU_FEATURE (AVX))
- cpu_features->feature[index_arch_AVX_Usable]
- |= bit_arch_AVX_Usable;
-#if index_arch_AVX2_Usable != index_arch_AVX_Fast_Unaligned_Load
-# error index_arch_AVX2_Usable != index_arch_AVX_Fast_Unaligned_Load
-#endif
- /* Determine if AVX2 is usable. Unaligned load with 256-bit
- AVX registers are faster on processors with AVX2. */
- if (HAS_CPU_FEATURE (AVX2))
- cpu_features->feature[index_arch_AVX2_Usable]
- |= bit_arch_AVX2_Usable | bit_arch_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 (HAS_CPU_FEATURE (AVX512F))
- {
- cpu_features->feature[index_arch_AVX512F_Usable]
- |= bit_arch_AVX512F_Usable;
- /* Determine if AVX512DQ is usable. */
- if (HAS_CPU_FEATURE (AVX512DQ))
- cpu_features->feature[index_arch_AVX512DQ_Usable]
- |= bit_arch_AVX512DQ_Usable;
- }
- }
- /* Determine if FMA is usable. */
- if (HAS_CPU_FEATURE (FMA))
- cpu_features->feature[index_arch_FMA_Usable]
- |= bit_arch_FMA_Usable;
- /* Determine if FMA4 is usable. */
- if (HAS_CPU_FEATURE (FMA4))
- cpu_features->feature[index_arch_FMA4_Usable]
- |= bit_arch_FMA4_Usable;
- }
- }
-
#if !HAS_CPUID
no_cpuid:
#endif
diff --git a/sysdeps/x86/cpu-features.h b/sysdeps/x86/cpu-features.h
index 0624a92..e06eb7e 100644
--- a/sysdeps/x86/cpu-features.h
+++ b/sysdeps/x86/cpu-features.h
@@ -204,11 +204,17 @@ extern const struct cpu_features *__get_cpu_features (void)
# endif
+/* Only used directly in cpu-features.c. */
+# define CPU_FEATURES_CPU_P(ptr, name) \
+ ((ptr->cpuid[index_cpu_##name].reg_##name & (bit_cpu_##name)) != 0)
+# define CPU_FEATURES_ARCH_P(ptr, name) \
+ ((ptr->feature[index_arch_##name] & (bit_arch_##name)) != 0)
+
/* HAS_* evaluates to true if we may use the feature at runtime. */
# define HAS_CPU_FEATURE(name) \
- ((__get_cpu_features ()->cpuid[index_cpu_##name].reg_##name & (bit_cpu_##name)) != 0)
+ CPU_FEATURES_CPU_P (__get_cpu_features (), name)
# define HAS_ARCH_FEATURE(name) \
- ((__get_cpu_features ()->feature[index_arch_##name] & (bit_arch_##name)) != 0)
+ CPU_FEATURES_ARCH_P (__get_cpu_features (), name)
# define index_cpu_CX8 COMMON_CPUID_INDEX_1
# define index_cpu_CMOV COMMON_CPUID_INDEX_1