[clang] [HLSL] add BuiltinsHLSL and set it up as target builtins. (PR #81902)

[Justin Bogner via cfe-commits]

https://github.com/bogner requested changes to this pull request.

Hm, on further thought tying the "HLSL" intrinsics to the DirectX backend as target intrinsics like this is probably going to shoot us in the foot with respect to SPIR-V. I think we need to rethink this, and if we are going with target intrinsics they should probably be DirectX branded rather than HLSL...

https://github.com/llvm/llvm-project/pull/81902