About the Intrinsic(builtin), where is it's definition?

Beginners
1

Hi
for example, __builtin_rvv_vsseg5e8_v seems a Intrinsic function, where is it’s definition at clang/llvm? thanks

2

It’s autogenerated by clang/include/clang/Basic/riscv_vector.td

I believe that creates tools/clang/include/clang/Basic/riscv_vector_builtins.inc in the build directory.

3

yes, at the riscv_vector_builtins.inc, have below two macro define:
#define RISCVV_BUILTIN(ID, TYPE, ATTRS) TARGET_BUILTIN(ID, TYPE, ATTRS, “zve32x”)
RISCVV_BUILTIN(__builtin_rvv_vsseg5e8_v,“”, “n”)

define TARGET_BUILTIN(ID, TYPE, ATTRS, FEATURE) BUILTIN(ID, TYPE, ATTRS)

Then can find BUILTINstrong text in the file llvm/clang/include/Basic/Builtins.def , and can know the detail of the BUILTIN parameter.

but hope to know BUILTIN() detailed implement, thanks.

4

The implementation is also created by tablegen from riscv_vector.td. It’s in tools/clang/include/clang/Basic/riscv_vector_builtin_cg.inc which is included by clang/lib/CodeGen/CGBuiltin.cpp

The LLVM intrinsics are defined in llvm/include/llvm/IR/IntrinsicsRISCV.td

The mapping of intrinsics to instructions is mostly in llvm/lib/Target/RISCV/RISCVInstrInfoVPseudos.td

5

at riscv_vector_builtin_cg.inc, it will call api to create llvm IR(have llvm intrinsics ), later map the intrinsics IR to instructions ?