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

[via llvm-commits]

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@@ -5819,14 +5907,14 @@ void VPlanTransforms::optimizeFindIVReductions(VPlan &Plan,
 
       VPBuilder LoopBuilder(BackedgeVal->getDefiningRecipe());
       VPValue *AnyOfCond = Cond;
-      if (TrueVal == PhiR)
+      if (OrigSelectR->getOperand(1) == PhiR)
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ayalz wrote:

Independent: may be good to canonicalize Find Last Recurrence cycles in VPlan such that PhiR always feeds the FindLastSelect as its last operand, negating the Cond feeding it if needed.

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