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

[via llvm-commits]

================
@@ -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);
----------------
ayalz wrote:

Connecting entry VPBB to scalar preheader VPBB is done here as part of introducing the conditional branch at end of entry IRBB?

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