[clang] [HLSL] Use icmp ne instead of trunc on boolean load (PR #221105)

[Sarah Spall via cfe-commits]

https://github.com/spall commented:

We shouldn't allow the user to specify the truncation mode, so we should always set load from bool to be compare to zero. If the user specifies the truncation mode we should emit a warning telling them its being ignored.

We should add a test to clang/test/Driver to check the correct flag is generated when clang-dxc is invoked. 


https://github.com/llvm/llvm-project/pull/221105