New named metadata "dx.entryPoints" is added to save all entries.
Each entry is in format of
!{ptr to function, name, signature, resource table, extra}
For compute shader, the extra will save num of threads in format of {i32 x, i32 y, i32 z}
For library profile, an empty entry will be added to save the resource table for the library.
Signature and resource table metadata is not generated yet.
Differential Revision: https://reviews.llvm.org/D131807
This captures the target shader model and pipeline stage into the DXIL
metadata for consumption by the DirectX runtime.
Reviewed By: python3kgae
Differential Revision: https://reviews.llvm.org/D134469
