[llvm] [VPlan] Rewrite sinkScalarOperands in preparation to extend (PR #151696)

[Florian Hahn via llvm-commits]

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@@ -131,60 +131,63 @@ bool VPlanTransforms::tryToConvertVPInstructionsToVPRecipes(
 }
 
 static bool sinkScalarOperands(VPlan &Plan) {
-  auto Iter = vp_depth_first_deep(Plan.getEntry());
+  bool ScalarVFOnly = Plan.hasScalarVFOnly();
   bool Changed = false;
   // First, collect the operands of all recipes in replicate blocks as seeds for
   // sinking.
   SetVector<std::pair<VPBasicBlock *, VPSingleDefRecipe *>> WorkList;
-  for (VPRegionBlock *VPR : VPBlockUtils::blocksOnly<VPRegionBlock>(Iter)) {
+  for (VPRegionBlock *VPR : VPBlockUtils::blocksOnly<VPRegionBlock>(
+           vp_depth_first_deep(Plan.getEntry()))) {
     VPBasicBlock *EntryVPBB = VPR->getEntryBasicBlock();
     if (!VPR->isReplicator() || EntryVPBB->getSuccessors().size() != 2)
       continue;
-    VPBasicBlock *VPBB = dyn_cast<VPBasicBlock>(EntryVPBB->getSuccessors()[0]);
+    VPBasicBlock *VPBB =
+        dyn_cast<VPBasicBlock>(EntryVPBB->getSuccessors().front());
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fhahn wrote:

this can be `cast<>` I think

https://github.com/llvm/llvm-project/pull/151696