[llvm] [VPlan] Optimize FindLast of (binop %IV, live-in) by sinking. (PR #183911)

[Florian Hahn via llvm-commits]

================
@@ -5794,16 +5861,40 @@ void VPlanTransforms::optimizeFindIVReductions(VPlan &Plan,
         BackedgeVal,
         match_fn(m_VPInstruction<VPInstruction::ComputeReductionResult>())));
 
+    // If IV is an expression to sink, create a new select that tracks the
+    // underlying IV directly and update the backedge value.
+    auto *OrigSelectR = FindLastSelect->getDefiningRecipe();
----------------
fhahn wrote:

updated thanks

https://github.com/llvm/llvm-project/pull/183911