[llvm] [VPlan] Update scalar induction resume values in VPlan. (PR #110577)

[Florian Hahn via llvm-commits]

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@@ -2611,27 +2624,21 @@ PHINode *InnerLoopVectorizer::createInductionResumeValue(
     }
   }
 
-  // Create phi nodes to merge from the backedge-taken check block.
-  PHINode *BCResumeVal =
-      PHINode::Create(OrigPhi->getType(), 3, "bc.resume.val",
-                      LoopScalarPreHeader->getFirstNonPHIIt());
-  // Copy original phi DL over to the new one.
-  BCResumeVal->setDebugLoc(OrigPhi->getDebugLoc());
-
-  // The new PHI merges the original incoming value, in case of a bypass,
-  // or the value at the end of the vectorized loop.
-  BCResumeVal->addIncoming(EndValue, LoopMiddleBlock);
-
-  // Fix the scalar body counter (PHI node).
-  // The old induction's phi node in the scalar body needs the truncated
-  // value.
-  for (BasicBlock *BB : BypassBlocks)
-    BCResumeVal->addIncoming(II.getStartValue(), BB);
+  auto *ResumePhiRecipe = ScalarPHBuilder.createNaryOp(
+      VPInstruction::ResumePhi,
+      {Plan.getOrAddLiveIn(EndValue), Plan.getOrAddLiveIn(II.getStartValue())},
+      OrigPhi->getDebugLoc(), "bc.resume.val");
+  assert(PhiR->getNumOperands() == 0 && "PhiR should not have any operands");
+  PhiR->addOperand(ResumePhiRecipe);
 
-  if (AdditionalBypass.first)
-    BCResumeVal->setIncomingValueForBlock(AdditionalBypass.first,
-                                          EndValueFromAdditionalBypass);
-  return BCResumeVal;
+  if (AdditionalBypass.first) {
+    // Store the bypass values here, as they need to be added to their phi nodes
+    // after the epilogue skeleton has been created.
----------------
fhahn wrote:

Added, thanks

https://github.com/llvm/llvm-project/pull/110577