[llvm] [VPlan] Connect Entry to scalar preheader during initial construction. (PR #140132)

[Florian Hahn via llvm-commits]

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@@ -2463,9 +2460,6 @@ void InnerLoopVectorizer::emitIterationCountCheck(BasicBlock *Bypass) {
     setBranchWeights(BI, MinItersBypassWeights, /*IsExpected=*/false);
   ReplaceInstWithInst(TCCheckBlock->getTerminator(), &BI);
   LoopBypassBlocks.push_back(TCCheckBlock);
-
-  // TODO: Wrap LoopVectorPreHeader in VPIRBasicBlock here.
-  introduceCheckBlockInVPlan(TCCheckBlock);
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fhahn wrote:

TCCheckBlock is the same block as the VPlan entry block. Before the change, we needed special logic to not create a new VPIRBB for this call.

https://github.com/llvm/llvm-project/pull/140132