Function attribute for standard vector calling convention variant: riscv_vector_cc #67
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cmuellner
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Feb 1, 2024
…scv_vector_cc Standard vector calling convention variant will only enabled when function has vector argument or returing 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. ```c void foo() __attribute__((riscv_vector_cc)); ```
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cmuellner
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Feb 1, 2024
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(copying my comment from #68 since it applies to both) Stylistically, since this is a well-defined RISC-V specific ABI attribute independent of any GNU extensions, I wonder if it should be I believe that this needs to be included in C++ function pointer mangling to support natural uses (although this doesn't work on aarch64). Do the rules for that need to be specified here? LGTM otherwise. |
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Update:
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Let me ask our folks to implement that in LLVM and GCC. |
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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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. riscv-non-isa/riscv-c-api-doc#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.
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GCC and clang/LLVM implementation has merged into trunk[1][2] |
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Standard vector calling convention variant has landed in psABI now, and the implementation also merged into GCC trunk, LLVM part are also under reviewing, and this attribute has mentioned during the discussion, but seems like we don't document that yet.
Standard vector calling convention variant will only enabled when function has vector argument or returing 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.