From 0058b10814afd8f1ea031b11f3c4ac226fa60d79 Mon Sep 17 00:00:00 2001 From: Wangyang Guo Date: Mon, 24 Jan 2022 02:59:56 +0000 Subject: [PATCH] Only avoid short distance REP MOVSB on ICX --- sysdeps/x86/cacheinfo.h | 9 +++++++++ sysdeps/x86/cpu-features.c | 5 +++++ .../include/cpu-features-preferred_feature_index_1.def | 1 + sysdeps/x86/sysdep.h | 3 +++ sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S | 5 +++++ 5 files changed, 23 insertions(+) diff --git a/sysdeps/x86/cacheinfo.h b/sysdeps/x86/cacheinfo.h index 02556961..7af8575d 100644 --- a/sysdeps/x86/cacheinfo.h +++ b/sysdeps/x86/cacheinfo.h @@ -45,6 +45,11 @@ long int __x86_rep_movsb_threshold attribute_hidden = 2048; /* Threshold to use Enhanced REP STOSB. */ long int __x86_rep_stosb_threshold attribute_hidden = 2048; +/* Non-zero to avoid short distance REP MOVSB. */ +//int __x86_avoid_short_distance_rep_movsb attribute_hidden; +/* String/memory function control. */ +int __x86_string_control attribute_hidden; + static void get_common_cache_info (long int *shared_ptr, unsigned int *threads_ptr, long int core) @@ -421,6 +426,10 @@ init_cacheinfo (void) else __x86_rep_movsb_threshold = rep_movsb_threshold; + if (CPU_FEATURES_ARCH_P (cpu_features, Avoid_Short_Distance_REP_MOVSB)) + __x86_string_control + |= X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB; + # if HAVE_TUNABLES __x86_rep_stosb_threshold = cpu_features->rep_stosb_threshold; # endif diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c index 91042505..22b45c72 100644 --- a/sysdeps/x86/cpu-features.c +++ b/sysdeps/x86/cpu-features.c @@ -526,6 +526,11 @@ init_cpu_features (struct cpu_features *cpu_features) else cpu_features->preferred[index_arch_Prefer_No_AVX512] |= bit_arch_Prefer_No_AVX512; + + /* Avoid avoid short distance REP MOVSB on processor with FSRM. */ + if (CPU_FEATURES_CPU_P (cpu_features, FSRM)) + cpu_features->preferred[index_arch_Avoid_Short_Distance_REP_MOVSB] + |= bit_arch_Avoid_Short_Distance_REP_MOVSB; } /* This spells out "AuthenticAMD". */ else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65) diff --git a/sysdeps/x86/include/cpu-features-preferred_feature_index_1.def b/sysdeps/x86/include/cpu-features-preferred_feature_index_1.def index 17a5cc42..e7277b33 100644 --- a/sysdeps/x86/include/cpu-features-preferred_feature_index_1.def +++ b/sysdeps/x86/include/cpu-features-preferred_feature_index_1.def @@ -32,3 +32,4 @@ BIT (Prefer_ERMS) BIT (Prefer_FSRM) BIT (Prefer_No_AVX512) BIT (MathVec_Prefer_No_AVX512) +BIT (Avoid_Short_Distance_REP_MOVSB) diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h index f41f4ebd..4ac93a95 100644 --- a/sysdeps/x86/sysdep.h +++ b/sysdeps/x86/sysdep.h @@ -57,6 +57,9 @@ enum cf_protection_level #define STATE_SAVE_MASK \ ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 6) | (1 << 7)) +/* Avoid short distance REP MOVSB. */ +#define X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB (1 << 0) + #ifdef __ASSEMBLER__ /* Syntactic details of assembler. */ diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S index 07299dc0..4aa65555 100644 --- a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S +++ b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S @@ -244,12 +244,16 @@ L(movsb): /* Avoid slow backward REP MOVSB. */ jb L(more_8x_vec_backward) # if AVOID_SHORT_DISTANCE_REP_MOVSB + andl $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) + jz 3f movq %rdi, %rcx subq %rsi, %rcx jmp 2f # endif 1: # if AVOID_SHORT_DISTANCE_REP_MOVSB + andl $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) + jz 3f movq %rsi, %rcx subq %rdi, %rcx 2: @@ -257,6 +261,7 @@ L(movsb): is N*4GB + [1..63] with N >= 0. */ cmpl $63, %ecx jbe L(more_2x_vec) /* Avoid "rep movsb" if ECX <= 63. */ +3: # endif movq %rdx, %rcx rep movsb -- 2.27.0