[llvm] [VPlan] Simplify branch on False in VPlan transform (NFC). (PR #140409)

[via llvm-commits]

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@@ -2379,11 +2379,9 @@ void InnerLoopVectorizer::introduceCheckBlockInVPlan(BasicBlock *CheckIRBB) {
   PreVectorPH->swapSuccessors();
 
   // We just connected a new block to the scalar preheader. Update all
-  // ResumePhis by adding an incoming value for it, replicating the last value.
-  for (VPRecipeBase &R : *cast<VPBasicBlock>(ScalarPH)) {
-    auto *ResumePhi = dyn_cast<VPInstruction>(&R);
-    if (!ResumePhi || ResumePhi->getOpcode() != VPInstruction::ResumePhi)
-      continue;
+  // VPPhis by adding an incoming value for it, replicating the last value.
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ayalz wrote:

nit: take the number of ScalarPH predecessors once, here, reuse it repeatedly inside the loop, asserting it is one more than the number of ResumePhi's operands.

https://github.com/llvm/llvm-project/pull/140409