[llvm] [VPlan] Strip VPDT's default constructor (NFC) (PR #162692)

[Ramkumar Ramachandra via llvm-commits]

https://github.com/artagnon created https://github.com/llvm/llvm-project/pull/162692

None

>From ae4d3dcb2e6a132e62c5d9e19861ff24d212809e Mon Sep 17 00:00:00 2001
From: Ramkumar Ramachandra <ramkumar.ramachandra at codasip.com>
Date: Thu, 9 Oct 2025 17:24:39 +0100
Subject: [PATCH] [VPlan] Strip VPDT's default constructor (NFC)

---
 llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp | 6 ++----
 llvm/lib/Transforms/Vectorize/VPlanDominatorTree.h  | 1 -
 llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp   | 9 +++------
 llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp     | 3 +--
 4 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index 81deba2932ef8..750e08f028042 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -480,8 +480,7 @@ static void createExtractsForLiveOuts(VPlan &Plan, VPBasicBlock *MiddleVPBB) {
 
 static void addInitialSkeleton(VPlan &Plan, Type *InductionTy, DebugLoc IVDL,
                                PredicatedScalarEvolution &PSE, Loop *TheLoop) {
-  VPDominatorTree VPDT;
-  VPDT.recalculate(Plan);
+  VPDominatorTree VPDT(Plan);
 
   auto *HeaderVPBB = cast<VPBasicBlock>(Plan.getEntry()->getSingleSuccessor());
   canonicalHeaderAndLatch(HeaderVPBB, VPDT);
@@ -623,8 +622,7 @@ void VPlanTransforms::addMiddleCheck(VPlan &Plan,
 }
 
 void VPlanTransforms::createLoopRegions(VPlan &Plan) {
-  VPDominatorTree VPDT;
-  VPDT.recalculate(Plan);
+  VPDominatorTree VPDT(Plan);
   for (VPBlockBase *HeaderVPB : vp_post_order_shallow(Plan.getEntry()))
     if (canonicalHeaderAndLatch(HeaderVPB, VPDT))
       createLoopRegion(Plan, HeaderVPB);
diff --git a/llvm/lib/Transforms/Vectorize/VPlanDominatorTree.h b/llvm/lib/Transforms/Vectorize/VPlanDominatorTree.h
index 577432fb9a865..44506f5ac3e81 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanDominatorTree.h
+++ b/llvm/lib/Transforms/Vectorize/VPlanDominatorTree.h
@@ -39,7 +39,6 @@ class VPDominatorTree : public DominatorTreeBase<VPBlockBase, false> {
   using Base = DominatorTreeBase<VPBlockBase, false>;
 
 public:
-  VPDominatorTree() = default;
   explicit VPDominatorTree(VPlan &Plan) { recalculate(Plan); }
 
   /// Returns true if \p A properly dominates \p B.
diff --git a/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp b/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
index c8a2d84a535d3..1d1e40b9fa0c3 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
@@ -1899,8 +1899,7 @@ static bool hoistPreviousBeforeFORUsers(VPFirstOrderRecurrencePHIRecipe *FOR,
 
 bool VPlanTransforms::adjustFixedOrderRecurrences(VPlan &Plan,
                                                   VPBuilder &LoopBuilder) {
-  VPDominatorTree VPDT;
-  VPDT.recalculate(Plan);
+  VPDominatorTree VPDT(Plan);
 
   SmallVector<VPFirstOrderRecurrencePHIRecipe *> RecurrencePhis;
   for (VPRecipeBase &R :
@@ -3011,8 +3010,7 @@ void VPlanTransforms::createInterleaveGroups(
   // Interleave memory: for each Interleave Group we marked earlier as relevant
   // for this VPlan, replace the Recipes widening its memory instructions with a
   // single VPInterleaveRecipe at its insertion point.
-  VPDominatorTree VPDT;
-  VPDT.recalculate(Plan);
+  VPDominatorTree VPDT(Plan);
   for (const auto *IG : InterleaveGroups) {
     auto *Start =
         cast<VPWidenMemoryRecipe>(RecipeBuilder.getRecipe(IG->getMember(0)));
@@ -3652,8 +3650,7 @@ void VPlanTransforms::materializeBroadcasts(VPlan &Plan) {
     return;
 
 #ifndef NDEBUG
-  VPDominatorTree VPDT;
-  VPDT.recalculate(Plan);
+  VPDominatorTree VPDT(Plan);
 #endif
 
   SmallVector<VPValue *> VPValues;
diff --git a/llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp b/llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp
index 013ea2e883534..0aaf455277180 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp
@@ -490,8 +490,7 @@ bool VPlanVerifier::verify(const VPlan &Plan) {
 }
 
 bool llvm::verifyVPlanIsValid(const VPlan &Plan, bool VerifyLate) {
-  VPDominatorTree VPDT;
-  VPDT.recalculate(const_cast<VPlan &>(Plan));
+  VPDominatorTree VPDT(const_cast<VPlan &>(Plan));
   VPTypeAnalysis TypeInfo(Plan);
   VPlanVerifier Verifier(VPDT, TypeInfo, VerifyLate);
   return Verifier.verify(Plan);