From 37ef938fd9cdea1c9f87b17f49a935f729374f1d Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 27 Feb 2023 10:55:46 +0100
Subject: [PATCH] target/i386: add FZRM, FSRS, FSRC

These are three more markers for string operation optimizations.
They can all be added to TCG, whose string operations are more or
less as fast as they can be for short lengths.

Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/cpu.c | 7 ++++---
 target/i386/cpu.h | 7 +++++++
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index e3cea8397c..7122af303d 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -661,7 +661,8 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1,
           /* CPUID_7_0_ECX_OSPKE is dynamic */ \
           CPUID_7_0_ECX_LA57 | CPUID_7_0_ECX_PKS)
 #define TCG_7_0_EDX_FEATURES 0
-#define TCG_7_1_EAX_FEATURES 0
+#define TCG_7_1_EAX_FEATURES (CPUID_7_1_EAX_FZRM | CPUID_7_1_EAX_FSRS | \
+          CPUID_7_1_EAX_FSRC)
 #define TCG_APM_FEATURES 0
 #define TCG_6_EAX_FEATURES CPUID_6_EAX_ARAT
 #define TCG_XSAVE_FEATURES (CPUID_XSAVE_XSAVEOPT | CPUID_XSAVE_XGETBV1)
@@ -871,8 +872,8 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .feat_names = {
             NULL, NULL, NULL, NULL,
             "avx-vnni", "avx512-bf16", NULL, NULL,
-            NULL, NULL, NULL, NULL,
-            NULL, NULL, NULL, NULL,
+            NULL, NULL, "fzrm", "fsrs",
+            "fsrc", NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 4f7fa87b95..7a32dabf12 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -876,6 +876,13 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
 #define CPUID_7_1_EAX_AVX_VNNI          (1U << 4)
 /* AVX512 BFloat16 Instruction */
 #define CPUID_7_1_EAX_AVX512_BF16       (1U << 5)
+/* Fast Zero REP MOVS */
+#define CPUID_7_1_EAX_FZRM              (1U << 10)
+/* Fast Short REP STOS */
+#define CPUID_7_1_EAX_FSRS              (1U << 11)
+/* Fast Short REP CMPS/SCAS */
+#define CPUID_7_1_EAX_FSRC              (1U << 12)
+
 /* XFD Extend Feature Disabled */
 #define CPUID_D_1_EAX_XFD               (1U << 4)
 
-- 
2.27.0