[llvm] [SPIR-V] Support optimization of branching with analyzeBranch/removeBranch/insertBranch functions (PR #110653)

[Vyacheslav Levytskyy via llvm-commits]

VyacheslavLevytskyy wrote:

@Keenuts Thank you for a good advice to be careful with analyzeBranch(). Testing and codegen source code helps to realize that the only safe option is to disable analyzeBranch(). One possible alternative to this would be to just entirely remove it from SPIRVInstrInfo, relying on default implementation. However, it seems better to keep it explicitly implemented with the comment as a way to document reasons to don't play with it in future. Please have a look at the result.

https://github.com/llvm/llvm-project/pull/110653