[llvm] [AMDGPU][AMDGPUDemoteSCCBranchToExecz] demote s_cbranch_scc0/1 branches into vcmp + s_cbranch_execz branches (PR #110284)

[Juan Manuel Martinez Caamaño via llvm-commits]

jmmartinez wrote:

> My intuition is that something has gone wrong upstream of this if this is a profitable transformation. Do you have a more complete example of something this helps?

I'm going to check what's going on with the whole CK kernel to give some more context.

I'd expect all the branches to be lowered to pseudo instructions and then to the actual instruction in `SILowerControlFlow`. This transformation would be placed in there if that was the case. Instead, these branches are created early in `AMDGPUDagToDagISel::SelectBRCOND`.

https://github.com/llvm/llvm-project/pull/110284