Ping. xuli1@eswincomputing.com From: Li Xu Date: 2024-02-27 09:17 To: gcc-patches CC: kito.cheng; palmer; juzhe.zhong; zhengyu; xuli Subject: [PATCH] RISC-V: Add riscv_vector_cc function attribute From: xuli Standard vector calling convention variant will only enabled when function has vector argument or returning value by default, however user may also want to invoke function without that during a vectorized loop at some situation, but it will cause a huge performance penalty due to vector register store/restore. So user can declare function with this riscv_vector_cc attribute like below, that could enforce function will use standard vector calling convention variant. void foo() __attribute__((riscv_vector_cc)); [[riscv::vector_cc]] void foo(); // For C++11 and C23 For more details please reference the below link. https://github.com/riscv-non-isa/riscv-c-api-doc/pull/67 gcc/ChangeLog: * config/riscv/riscv.cc (TARGET_GNU_ATTRIBUTES): Add riscv_vector_cc attribute to riscv_attribute_table. (riscv_vector_cc_function_p): Return true if FUNC is a riscv_vector_cc function. (riscv_fntype_abi): Add riscv_vector_cc attribute check. * doc/extend.texi: Add riscv_vector_cc attribute description. gcc/testsuite/ChangeLog: * g++.target/riscv/rvv/base/attribute-riscv_vector_cc-error.C: New test. * gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-callee-saved.c: New test. * gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-error.c: New test. --- gcc/config/riscv/riscv.cc | 55 ++++++-- gcc/doc/extend.texi | 12 ++ .../base/attribute-riscv_vector_cc-error.C | 22 ++++ .../attribute-riscv_vector_cc-callee-saved.c | 117 ++++++++++++++++++ .../base/attribute-riscv_vector_cc-error.c | 11 ++ 5 files changed, 209 insertions(+), 8 deletions(-) create mode 100644 gcc/testsuite/g++.target/riscv/rvv/base/attribute-riscv_vector_cc-error.C create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-callee-saved.c create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-error.c diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc index 4100abc9dd1..7f37f231796 100644 --- a/gcc/config/riscv/riscv.cc +++ b/gcc/config/riscv/riscv.cc @@ -537,24 +537,52 @@ static tree riscv_handle_fndecl_attribute (tree *, tree, tree, int, bool *); static tree riscv_handle_type_attribute (tree *, tree, tree, int, bool *); /* Defining target-specific uses of __attribute__. */ -TARGET_GNU_ATTRIBUTES (riscv_attribute_table, +static const attribute_spec riscv_gnu_attributes[] = { /* Syntax: { name, min_len, max_len, decl_required, type_required, function_type_required, affects_type_identity, handler, exclude } */ /* The attribute telling no prologue/epilogue. */ - { "naked", 0, 0, true, false, false, false, - riscv_handle_fndecl_attribute, NULL }, + {"naked", 0, 0, true, false, false, false, riscv_handle_fndecl_attribute, + NULL}, /* This attribute generates prologue/epilogue for interrupt handlers. */ - { "interrupt", 0, 1, false, true, true, false, - riscv_handle_type_attribute, NULL }, + {"interrupt", 0, 1, false, true, true, false, riscv_handle_type_attribute, + NULL}, /* The following two are used for the built-in properties of the Vector type and are not used externally */ {"RVV sizeless type", 4, 4, false, true, false, true, NULL, NULL}, - {"RVV type", 0, 0, false, true, false, true, NULL, NULL} -}); + {"RVV type", 0, 0, false, true, false, true, NULL, NULL}, + /* This attribute is used to declare a function, forcing it to use the + standard vector calling convention variant. Syntax: + __attribute__((riscv_vector_cc)). */ + {"riscv_vector_cc", 0, 0, false, true, true, true, NULL, NULL} +}; + +static const scoped_attribute_specs riscv_gnu_attribute_table = +{ + "gnu", {riscv_gnu_attributes} +}; + +static const attribute_spec riscv_attributes[] = +{ + /* This attribute is used to declare a function, forcing it to use the + standard vector calling convention variant. Syntax: + [[riscv::vector_cc]]. */ + {"vector_cc", 0, 0, false, true, true, true, NULL, NULL} +}; + +static const scoped_attribute_specs riscv_nongnu_attribute_table = +{ + "riscv", {riscv_attributes} +}; + +static const scoped_attribute_specs *const riscv_attribute_table[] = +{ + &riscv_gnu_attribute_table, + &riscv_nongnu_attribute_table +}; /* Order for the CLOBBERs/USEs of gpr_save. */ static const unsigned gpr_save_reg_order[] = { @@ -5425,6 +5453,16 @@ riscv_arguments_is_vector_type_p (const_tree fntype) return false; } +/* Return true if FUNC is a riscv_vector_cc function. + For more details please reference the below link. + https://github.com/riscv-non-isa/riscv-c-api-doc/pull/67 */ +static bool +riscv_vector_cc_function_p (const_tree fntype) +{ + return lookup_attribute ("vector_cc", TYPE_ATTRIBUTES (fntype)) != NULL_TREE + || lookup_attribute ("riscv_vector_cc", TYPE_ATTRIBUTES (fntype)) != NULL_TREE; +} + /* Implement TARGET_FNTYPE_ABI. */ static const predefined_function_abi & @@ -5434,7 +5472,8 @@ riscv_fntype_abi (const_tree fntype) reference the below link. https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/389 */ if (riscv_return_value_is_vector_type_p (fntype) - || riscv_arguments_is_vector_type_p (fntype)) + || riscv_arguments_is_vector_type_p (fntype) + || riscv_vector_cc_function_p (fntype)) return riscv_v_abi (); return default_function_abi; diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index 2135dfde9c8..afe486ba47b 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -6314,6 +6314,18 @@ Permissible values for this parameter are @code{user}, @code{supervisor}, and @code{machine}. If there is no parameter, then it defaults to @code{machine}. +@cindex @code{riscv_vector_cc} function attribute, RISC-V +@item riscv_vector_cc +Use this attribute to force the function to use the vector calling +convention variant. +For more information on riscv_vector_cc, please see +@uref{https://github.com/riscv-non-isa/riscv-c-api-doc/pull/67} + +@smallexample +void foo() __attribute__((riscv_vector_cc)); +[[riscv::vector_cc]] void foo(); // For C++11 and C23 +@end smallexample + @end table The following target-specific function attributes are available for the diff --git a/gcc/testsuite/g++.target/riscv/rvv/base/attribute-riscv_vector_cc-error.C b/gcc/testsuite/g++.target/riscv/rvv/base/attribute-riscv_vector_cc-error.C new file mode 100644 index 00000000000..7a547b5e7ff --- /dev/null +++ b/gcc/testsuite/g++.target/riscv/rvv/base/attribute-riscv_vector_cc-error.C @@ -0,0 +1,22 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gcv -mabi=lp64d -O1" } */ + + +[[riscv::vector_cc]] void foo();// For C++11 and C23 + +[[riscv::vector_cc]] int var; /* { dg-warning "'vector_cc' attribute only applies to function types" } */ + +void __attribute__((riscv_vector_cc)) func(); +void __attribute__((riscv_vector_cc(1))) func_invalid(); /* { dg-error "wrong number of arguments specified for 'riscv_vector_cc' attribute" } */ + +void test_no_attribute(int); +void __attribute__((riscv_vector_cc)) test_no_attribute(int x) { } + +class test_cc { + __attribute__((riscv_vector_cc)) void member_func(); +}; + +void test_lambda() { + __attribute__((riscv_vector_cc)) auto lambda = []() { /* { dg-warning "'riscv_vector_cc' attribute only applies to function types" } */ + }; +} diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-callee-saved.c b/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-callee-saved.c new file mode 100644 index 00000000000..7db9d874bcd --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-callee-saved.c @@ -0,0 +1,117 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gcv -mabi=lp64d -O1" } */ +/* { dg-final { check-function-bodies "**" "" } } */ + +#include + +void __attribute__((riscv_vector_cc)) bar1 (int a); +void bar2 (); + +/* +** foo1: +** addi\tsp,sp,-16 +** sd\tra,8\(sp\) +** call\tbar1 +** ld\tra,8\(sp\) +** addi\tsp,sp,16 +** jr\tra +*/ +void __attribute__((riscv_vector_cc)) +foo1 (int a) +{ + bar1 (a); +} + +/* +** foo2: +** addi\tsp,sp,-16 +** sd\tra,8\(sp\) +** csrr\tt0,vlenb +** sub\tsp,sp,t0 +** vs1r\.v\tv1,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv2,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv3,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv4,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv5,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv6,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv7,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv24,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv25,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv26,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv27,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv28,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv29,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv30,0\(sp\) +** sub\tsp,sp,t0 +** vs1r\.v\tv31,0\(sp\) +** call\tbar2 +** csrr\tt0,vlenb +** vl1re64\.v\tv31,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv30,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv29,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv28,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv27,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv26,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv25,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv24,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv7,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv6,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv5,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv4,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv3,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv2,0\(sp\) +** add\tsp,sp,t0 +** vl1re64\.v\tv1,0\(sp\) +** add\tsp,sp,t0 +** ld\tra,8\(sp\) +** addi\tsp,sp,16 +** jr\tra +*/ +void __attribute__((riscv_vector_cc)) +foo2 (int a) +{ + int8_t data[1024]; + bar2 (); +} + +/* +** foo3: +** addi\tsp,sp,-16 +** sd\tra,8\(sp\) +** lw\ta0,0\(a0\) +** call\tbar1 +** ld\tra,8\(sp\) +** addi\tsp,sp,16 +** jr\tra +*/ +void +foo3 (int *a) +{ + bar1 (*a); +} diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-error.c b/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-error.c new file mode 100644 index 00000000000..ceb5e5bf6dd --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/rvv/base/attribute-riscv_vector_cc-error.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gcv -mabi=lp64d -O1" } */ + +__attribute__((riscv_vector_cc)) int var; /* { dg-warning "'riscv_vector_cc' attribute only applies to function types" } */ +[[riscv::vector_cc]] int var1; /* { dg-warning "'vector_cc' attribute only applies to function types" } */ + +void __attribute__((riscv_vector_cc)) func(); +void __attribute__((riscv_vector_cc(1))) func_invalid(); /* { dg-error "wrong number of arguments specified for 'riscv_vector_cc' attribute" } */ + +void test_no_attribute(int); +void __attribute__((riscv_vector_cc)) test_no_attribute(int x) { } -- 2.17.1