[HLSL] `main` is just a function

[llvm-beanz]

HLSL gives no special meaning to the function named main. It does give special handling to entry points, and the active entry point when building a freestanding shader. Those cases are handled by the HLSLShader attribute, which can be implicitly applied to main if no other entry is specified, rather than the function name.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Chris B (llvm-beanz)

HLSL gives no special meaning to the function named `main`. It does give special handling to _entry points_, and the _active entry point_ when building a freestanding shader. Those cases are handled by the HLSLShader attribute, which can be implicitly applied to `main` if no other entry is specified, rather than the function name.