[llvm] [VPlan] Add exit phi operands during initial construction (NFC). (PR #136455)

[via llvm-commits]

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@@ -9392,11 +9392,7 @@ collectUsersInExitBlocks(Loop *OrigLoop, VPRecipeBuilder &Builder,
         continue;
       }
 
-      PHINode &ExitPhi = ExitIRI->getIRPhi();
-      BasicBlock *ExitingBB = OrigLoop->getLoopLatch();
-      Value *IncomingValue = ExitPhi.getIncomingValueForBlock(ExitingBB);
-      VPValue *V = Builder.getVPValueOrAddLiveIn(IncomingValue);
-      ExitIRI->addOperand(V);
+      VPValue *V = ExitIRI->getOperand(0);
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ayalz wrote:

Worth asserting that ExitIRI has a single operand? Expected to match its single middle-block predecessor.

https://github.com/llvm/llvm-project/pull/136455