[llvm] [SPIR-V] Add SPIR-V structurizer (PR #97606)

[Steven Perron via llvm-commits]

Nathan =?utf-8?q?Gauër?= <brioche at google.com>,
Nathan =?utf-8?q?Gauër?= <brioche at google.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/97606 at github.com>


https://github.com/s-perron requested changes to this pull request.

Overall looks good, and I like how it is divided into small functions. That is made it easy to review.

However, I have a problem with the step that adds the selection merge instructions. We have disagreed on this general, but I think we need to implement it by looking at the merge blocks. We need to add a selection merge for every block that has multiple predecessors. That selection merge should be the immediate dominator of the block.

https://en.wikipedia.org/wiki/Dominator_(graph_theory)

https://github.com/llvm/llvm-project/pull/97606