From ff54abd2beebaa309762603bb7bf8f46ea530388 Mon Sep 17 00:00:00 2001 From: Hongyu Wang Date: Sun, 25 Jun 2023 09:50:21 +0800 Subject: [PATCH] i386: Sync tune_string with arch_string for target attribute arch=* For function with target attribute arch=*, current logic will set its tune to -mtune from command line so all target_clones will get same tuning flags which would affect the performance for each clone. Override tune with arch if tune was not explicitly specified to get proper tuning flags for target_clones. gcc/ChangeLog: * config/i386/i386-options.cc (ix86_valid_target_attribute_tree): Override tune_string with arch_string if tune_string is not explicitly specified. gcc/testsuite/ChangeLog: * gcc.target/i386/mvc17.c: New test. (cherry picked from commit 2916278d14e9ac28c361c396a67256acbebda6e8) --- gcc/config/i386/i386-options.cc | 6 +++++- gcc/testsuite/gcc.target/i386/mvc17.c | 11 +++++++++++ 2 files changed, 16 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.target/i386/mvc17.c diff --git a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc index 70ddcd284c4b..27d16986a2fa 100644 --- a/gcc/config/i386/i386-options.cc +++ b/gcc/config/i386/i386-options.cc @@ -1378,7 +1378,11 @@ ix86_valid_target_attribute_tree (tree fndecl, tree args, if (option_strings[IX86_FUNCTION_SPECIFIC_TUNE]) opts->x_ix86_tune_string = ggc_strdup (option_strings[IX86_FUNCTION_SPECIFIC_TUNE]); - else if (orig_tune_defaulted) + /* If we have explicit arch string and no tune string specified, set + tune_string to NULL and later it will be overriden by arch_string + so target clones can get proper optimization. */ + else if (option_strings[IX86_FUNCTION_SPECIFIC_ARCH] + || orig_tune_defaulted) opts->x_ix86_tune_string = NULL; /* If fpmath= is not set, and we now have sse2 on 32-bit, use it. */ diff --git a/gcc/testsuite/gcc.target/i386/mvc17.c b/gcc/testsuite/gcc.target/i386/mvc17.c new file mode 100644 index 000000000000..8b83c1aecb36 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/mvc17.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-require-ifunc "" } */ +/* { dg-options "-O2 -march=x86-64" } */ +/* { dg-final { scan-assembler-times "rep mov" 1 } } */ + +__attribute__((target_clones("default","arch=icelake-server"))) +void +foo (char *a, char *b, int size) +{ + __builtin_memcpy (a, b, size & 0x7F); +} -- 2.47.3