This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
[PATCH] x86: Set Prefer_No_VZEROUPPER if AVX512ER is available
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Mon, 17 Apr 2017 12:54:12 -0700
- Subject: [PATCH] x86: Set Prefer_No_VZEROUPPER if AVX512ER is available
- Authentication-results: sourceware.org; auth=none
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
Since AVX512ER is unique to Xeon Phi, set Prefer_No_VZEROUPPER if
AVX512ER is available.
Any comments?
H.J.
----
* sysdeps/x86/cpu-features.c (init_cpu_features): Set
Prefer_No_VZEROUPPER if AVX512ER is available.
* sysdeps/x86/cpu-features.h
(bit_cpu_AVX512PF): New.
(bit_cpu_AVX512ER): Likewise.
(bit_cpu_AVX512CD): Likewise.
(bit_cpu_AVX512BW): Likewise.
(bit_cpu_AVX512VL): Likewise.
(index_cpu_AVX512PF): Likewise.
(index_cpu_AVX512ER): Likewise.
(index_cpu_AVX512CD): Likewise.
(index_cpu_AVX512BW): Likewise.
(index_cpu_AVX512VL): Likewise.
(reg_AVX512PF): Likewise.
(reg_AVX512ER): Likewise.
(reg_AVX512CD): Likewise.
(reg_AVX512BW): Likewise.
(reg_AVX512VL): Likewise.
---
sysdeps/x86/cpu-features.c | 8 ++++++--
sysdeps/x86/cpu-features.h | 15 +++++++++++++++
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 33788ed..ae7f844 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -138,8 +138,6 @@ init_cpu_features (struct cpu_features *cpu_features)
case 0x57:
/* Knights Landing. Enable Silvermont optimizations. */
- cpu_features->feature[index_arch_Prefer_No_VZEROUPPER]
- |= bit_arch_Prefer_No_VZEROUPPER;
case 0x5c:
case 0x5f:
@@ -225,6 +223,12 @@ init_cpu_features (struct cpu_features *cpu_features)
cpu_features->feature[index_arch_AVX_Fast_Unaligned_Load]
|= bit_arch_AVX_Fast_Unaligned_Load;
+ /* Since AVX512ER is unique to Xeon Phi, set Prefer_No_VZEROUPPER
+ if AVX512ER is available. */
+ if (CPU_FEATURES_CPU_P (cpu_features, AVX512ER))
+ cpu_features->feature[index_arch_Prefer_No_VZEROUPPER]
+ |= bit_arch_Prefer_No_VZEROUPPER;
+
/* To avoid SSE transition penalty, use _dl_runtime_resolve_slow.
If XGETBV suports ECX == 1, use _dl_runtime_resolve_opt. */
cpu_features->feature[index_arch_Use_dl_runtime_resolve_slow]
diff --git a/sysdeps/x86/cpu-features.h b/sysdeps/x86/cpu-features.h
index 8ec1562..1583d65 100644
--- a/sysdeps/x86/cpu-features.h
+++ b/sysdeps/x86/cpu-features.h
@@ -63,6 +63,11 @@
#define bit_cpu_AVX2 (1 << 5)
#define bit_cpu_AVX512F (1 << 16)
#define bit_cpu_AVX512DQ (1 << 17)
+#define bit_cpu_AVX512PF (1 << 26)
+#define bit_cpu_AVX512ER (1 << 27)
+#define bit_cpu_AVX512CD (1 << 28)
+#define bit_cpu_AVX512BW (1 << 30)
+#define bit_cpu_AVX512VL (1u << 31)
/* XCR0 Feature flags. */
#define bit_XMM_state (1 << 1)
@@ -239,6 +244,11 @@ extern const struct cpu_features *__get_cpu_features (void)
# define index_cpu_AVX2 COMMON_CPUID_INDEX_7
# define index_cpu_AVX512F COMMON_CPUID_INDEX_7
# define index_cpu_AVX512DQ COMMON_CPUID_INDEX_7
+# define index_cpu_AVX512PF COMMON_CPUID_INDEX_7
+# define index_cpu_AVX512ER COMMON_CPUID_INDEX_7
+# define index_cpu_AVX512CD COMMON_CPUID_INDEX_7
+# define index_cpu_AVX512BW COMMON_CPUID_INDEX_7
+# define index_cpu_AVX512VL COMMON_CPUID_INDEX_7
# define index_cpu_ERMS COMMON_CPUID_INDEX_7
# define index_cpu_RTM COMMON_CPUID_INDEX_7
# define index_cpu_FMA COMMON_CPUID_INDEX_1
@@ -258,6 +268,11 @@ extern const struct cpu_features *__get_cpu_features (void)
# define reg_AVX2 ebx
# define reg_AVX512F ebx
# define reg_AVX512DQ ebx
+# define reg_AVX512PF ebx
+# define reg_AVX512ER ebx
+# define reg_AVX512CD ebx
+# define reg_AVX512BW ebx
+# define reg_AVX512VL ebx
# define reg_ERMS ebx
# define reg_RTM ebx
# define reg_FMA ecx
--
2.9.3