[clang] Adding `asuint` implementation to hlsl (PR #107292)

[Farzon Lotfi via cfe-commits]

farzonl wrote:

> @llvm-beanz I've implemented your suggestions. One issue I found is that the code generation will work with half types, which are not supported in the current implementation. Any suggestions into how to approach this?

is there a way to know if the use of `__builtin_bit_cast` came fro `asuint`? like maybe by checking if the return type is already set to uint?

if so then you could disallow  `half` types in HLSLSema.

https://github.com/llvm/llvm-project/pull/107292