[llvm] [VPlan] Use scalar VPPhi instead of VPWidenPHIRecipe in createPlainCFG. (PR #150847)

[Florian Hahn via llvm-commits]

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@@ -207,8 +205,8 @@ void PlainCFGBuilder::createVPInstructionsForVPBB(VPBasicBlock *VPBB,
       // Phi node's operands may have not been visited at this point. We create
       // an empty VPInstruction that we will fix once the whole plain CFG has
       // been built.
-      NewR = new VPWidenPHIRecipe(Phi, nullptr, Phi->getDebugLoc(), "vec.phi");
-      VPBB->appendRecipe(NewR);
+      NewR = VPIRBuilder.createScalarPhi({}, Phi->getDebugLoc(), "vec.phi");
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fhahn wrote:

For now it is scalar-phi only, but the distinction could go away in the later stages, if we decide to encode single-scalar/wide in for some recipes.

https://github.com/llvm/llvm-project/pull/150847