[llvm] [VPlan] Manage created blocks directly in VPlan. (NFC) (PR #120918)

[via llvm-commits]

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@@ -2477,7 +2477,7 @@ static void introduceCheckBlockInVPlan(VPlan &Plan, BasicBlock *CheckIRBB) {
     assert(PreVectorPH->getNumSuccessors() == 2 && "Expected 2 successors");
     assert(PreVectorPH->getSuccessors()[0] == ScalarPH &&
            "Unexpected successor");
-    VPIRBasicBlock *CheckVPIRBB = VPIRBasicBlock::fromBasicBlock(CheckIRBB);
+    VPIRBasicBlock *CheckVPIRBB = Plan.createVPIRBasicBlock(CheckIRBB);
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ayalz wrote:

This thought can be pursued as follow-up.

A builder can be initialized with VPlan. The builder would provide an API for creating blocks (including but not limited to), whose implementation registers the new block within VPlan. Would be good to create VPlan components consistently, rather than having the abovementioned four distinct mechanisms.

https://github.com/llvm/llvm-project/pull/120918