HLSL uses CreateRuntimeFunction for three intrinsics. This is pretty
unusual thing to do, and doesn't match what the rest of the file does.
I suspect this might be because these are convergent calls, but the
intrinsics themselves are already marked convergent, so it's not
necessary for clang to manually add the attribute.
This does lose the spir_func CC on the intrinsic declaration, but again,
CC should not be relevant to intrinsics at all.
``` - add clang builtin to Builtins.td
- link builtin in hlsl_intrinsics
- add codegen for spirv intrinsic and two directx intrinsics to retain
signedness information of the operands in CGBuiltin.cpp
- add semantic analysis in SemaHLSL.cpp
- add lowering of spirv intrinsic to spirv backend in
SPIRVInstructionSelector.cpp
- add lowering of directx intrinsics to WaveActiveOp dxil op in
DXIL.td
- add test cases to illustrate passespendent pr merges.
```
Resolves#99170