[llvm] [NaryReassociate] Teach NaryReassociate about UniformityAnalysis (PR #175167)

[Jay Foad via llvm-commits]

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@@ -379,14 +388,33 @@ NaryReassociatePass::tryReassociateGEPAtIndex(GetElementPtrInst *GEP,
 
     Value *LHS = AO->getOperand(0), *RHS = AO->getOperand(1);
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jayfoad wrote:

The existing code uses `LHS` and `RHS` throughout. Your new code adds uses of `AO->getOperandUse(0)` and `AO->getOperandUse(1)` which are harder to read. Can you refactor a bit so that names like `LHS` (or perhaps `LHSUse`) are used throughout? And the same for all the code you have touched.

https://github.com/llvm/llvm-project/pull/175167