[llvm] [LV] Vectorize selecting last IV of min/max element. (PR #141431)

Florian Hahn via llvm-commits llvm-commits at lists.llvm.org
Thu Sep 11 14:13:40 PDT 2025


https://github.com/fhahn updated https://github.com/llvm/llvm-project/pull/141431

>From 11870a25909b02efb5c7b2b12a71c651b839c708 Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Sun, 8 Jun 2025 21:46:21 +0100
Subject: [PATCH 1/5] [LV] Vectorize select min/max index.

Add support for vectorizing loops that select the index of the minimum or
maximum element. The patch implements vectorizing those patterns by
combining Min/Max and FindFirstIV reductions.

It extends matching Min/Max reductions to allow in-loop users that are
FindLastIV reductions. It records a flag indicating that the Min/Max
reduction is used by another reduction.

When creating reduction recipes, we process any reduction that has other
reduction users. The reduction using the min/max reduction needs adjusting
to compute the correct result:
 1. We need to find the first IV for which the condition based on the
    min/max reduction is true,
 2. Compare the partial min/max reduction result to its final value and,
 3. Select the lanes of the partial FindLastIV reductions which correspond
    to the lanes matching the min/max reduction result.
---
 .../Vectorize/LoopVectorizationLegality.cpp   |  21 +-
 .../Transforms/Vectorize/LoopVectorize.cpp    |  30 +-
 llvm/lib/Transforms/Vectorize/VPlan.h         |   9 +-
 .../Vectorize/VPlanConstruction.cpp           | 145 ++++++++++
 .../Transforms/Vectorize/VPlanTransforms.h    |   5 +
 .../LoopVectorize/AArch64/select-index.ll     | 264 ++++++++++++++---
 .../select-index-interleaving.ll              | 264 ++++++++++++++---
 .../LoopVectorize/select-smax-last-index.ll   | 218 +++++++++++---
 .../LoopVectorize/select-smin-last-index.ll   | 228 ++++++++++++---
 .../LoopVectorize/select-umax-last-index.ll   | 218 +++++++++++---
 .../LoopVectorize/select-umin-last-index.ll   | 272 +++++++++++++++---
 11 files changed, 1433 insertions(+), 241 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
index c47fd9421fddd..1ecb120cf1ed7 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
@@ -798,6 +798,7 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
   // For each block in the loop.
   for (BasicBlock *BB : TheLoop->blocks()) {
     // Scan the instructions in the block and look for hazards.
+    PHINode *UnclassifiedPhi = nullptr;
     for (Instruction &I : *BB) {
       if (auto *Phi = dyn_cast<PHINode>(&I)) {
         Type *PhiTy = Phi->getType();
@@ -887,12 +888,7 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
           addInductionPhi(Phi, ID, AllowedExit);
           continue;
         }
-
-        reportVectorizationFailure("Found an unidentified PHI",
-            "value that could not be identified as "
-            "reduction is used outside the loop",
-            "NonReductionValueUsedOutsideLoop", ORE, TheLoop, Phi);
-        return false;
+        UnclassifiedPhi = Phi;
       } // end of PHI handling
 
       // We handle calls that:
@@ -1043,6 +1039,19 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
         return false;
       }
     } // next instr.
+    if (UnclassifiedPhi && none_of(BB->phis(), [this](PHINode &P) {
+          auto I = Reductions.find(&P);
+          return I != Reductions.end() &&
+                 RecurrenceDescriptor::isFindLastIVRecurrenceKind(
+                     I->second.getRecurrenceKind());
+        })) {
+      reportVectorizationFailure("Found an unidentified PHI",
+                                 "value that could not be identified as "
+                                 "reduction is used outside the loop",
+                                 "NonReductionValueUsedOutsideLoop", ORE,
+                                 TheLoop, UnclassifiedPhi);
+      return false;
+    }
   }
 
   if (!PrimaryInduction) {
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 850c4a11edc67..cfd09dce3e6a4 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -7250,6 +7250,9 @@ static void fixReductionScalarResumeWhenVectorizingEpilog(
     Value *StartV = getStartValueFromReductionResult(EpiRedResult);
     Value *SentinelV = EpiRedResult->getOperand(2)->getLiveInIRValue();
     using namespace llvm::PatternMatch;
+    MainResumeValue = cast<VPInstruction>(EpiRedHeaderPhi->getStartValue())
+                          ->getOperand(0)
+                          ->getUnderlyingValue();
     Value *Cmp, *OrigResumeV, *CmpOp;
     [[maybe_unused]] bool IsExpectedPattern =
         match(MainResumeValue,
@@ -7260,7 +7263,11 @@ static void fixReductionScalarResumeWhenVectorizingEpilog(
          ((CmpOp == StartV && isGuaranteedNotToBeUndefOrPoison(CmpOp))));
     assert(IsExpectedPattern && "Unexpected reduction resume pattern");
     MainResumeValue = OrigResumeV;
+  } else {
+    if (auto *VPI = dyn_cast<VPInstruction>(EpiRedHeaderPhi->getStartValue()))
+      MainResumeValue = VPI->getOperand(0)->getUnderlyingValue();
   }
+
   PHINode *MainResumePhi = cast<PHINode>(MainResumeValue);
 
   // When fixing reductions in the epilogue loop we should already have
@@ -8276,9 +8283,6 @@ VPRecipeBase *VPRecipeBuilder::tryToCreateWidenRecipe(VPSingleDefRecipe *R,
       return Recipe;
 
     VPHeaderPHIRecipe *PhiRecipe = nullptr;
-    assert((Legal->isReductionVariable(Phi) ||
-            Legal->isFixedOrderRecurrence(Phi)) &&
-           "can only widen reductions and fixed-order recurrences here");
     VPValue *StartV = Operands[0];
     if (Legal->isReductionVariable(Phi)) {
       const RecurrenceDescriptor &RdxDesc = Legal->getRecurrenceDescriptor(Phi);
@@ -8291,12 +8295,17 @@ VPRecipeBase *VPRecipeBuilder::tryToCreateWidenRecipe(VPSingleDefRecipe *R,
       PhiRecipe = new VPReductionPHIRecipe(
           Phi, RdxDesc.getRecurrenceKind(), *StartV, CM.isInLoopReduction(Phi),
           CM.useOrderedReductions(RdxDesc), ScaleFactor);
-    } else {
+    } else if (Legal->isFixedOrderRecurrence(Phi)) {
       // TODO: Currently fixed-order recurrences are modeled as chains of
       // first-order recurrences. If there are no users of the intermediate
       // recurrences in the chain, the fixed order recurrence should be modeled
       // directly, enabling more efficient codegen.
       PhiRecipe = new VPFirstOrderRecurrencePHIRecipe(Phi, *StartV);
+    } else {
+      // Failed to identify phi as reduction or fixed-order recurrence. Keep the
+      // original VPWidenPHIRecipe for now, to be legalized later if possible.
+      setRecipe(Phi, R);
+      return nullptr;
     }
     // Add backedge value.
     PhiRecipe->addOperand(Operands[1]);
@@ -8481,7 +8490,7 @@ static void addScalarResumePhis(VPRecipeBuilder &Builder, VPlan &Plan,
     // TODO: Extract final value from induction recipe initially, optimize to
     // pre-computed end value together in optimizeInductionExitUsers.
     auto *VectorPhiR =
-        cast<VPHeaderPHIRecipe>(Builder.getRecipe(&ScalarPhiIRI->getIRPhi()));
+        cast<VPSingleDefRecipe>(Builder.getRecipe(&ScalarPhiIRI->getIRPhi()));
     if (auto *WideIVR = dyn_cast<VPWidenInductionRecipe>(VectorPhiR)) {
       if (VPInstruction *ResumePhi = addResumePhiRecipeForInduction(
               WideIVR, VectorPHBuilder, ScalarPHBuilder, TypeInfo,
@@ -8503,7 +8512,7 @@ static void addScalarResumePhis(VPRecipeBuilder &Builder, VPlan &Plan,
     // which for FORs is a vector whose last element needs to be extracted. The
     // start value provides the value if the loop is bypassed.
     bool IsFOR = isa<VPFirstOrderRecurrencePHIRecipe>(VectorPhiR);
-    auto *ResumeFromVectorLoop = VectorPhiR->getBackedgeValue();
+    auto *ResumeFromVectorLoop = VectorPhiR->getOperand(1);
     assert(VectorRegion->getSingleSuccessor() == Plan.getMiddleBlock() &&
            "Cannot handle loops with uncountable early exits");
     if (IsFOR)
@@ -8512,7 +8521,7 @@ static void addScalarResumePhis(VPRecipeBuilder &Builder, VPlan &Plan,
           "vector.recur.extract");
     StringRef Name = IsFOR ? "scalar.recur.init" : "bc.merge.rdx";
     auto *ResumePhiR = ScalarPHBuilder.createScalarPhi(
-        {ResumeFromVectorLoop, VectorPhiR->getStartValue()}, {}, Name);
+        {ResumeFromVectorLoop, VectorPhiR->getOperand(0)}, {}, Name);
     ScalarPhiIRI->addOperand(ResumePhiR);
   }
 }
@@ -8783,6 +8792,8 @@ VPlanPtr LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(
       VPRecipeBase *Recipe =
           RecipeBuilder.tryToCreateWidenRecipe(SingleDef, Range);
       if (!Recipe) {
+        if (isa<VPWidenPHIRecipe>(SingleDef))
+          continue;
         SmallVector<VPValue *, 4> Operands(R.operands());
         Recipe = RecipeBuilder.handleReplication(Instr, Operands, Range);
       }
@@ -8845,6 +8856,10 @@ VPlanPtr LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(
   // Adjust the recipes for any inloop reductions.
   adjustRecipesForReductions(Plan, RecipeBuilder, Range.Start);
 
+  // Try to convert remaining VPWidenPHIRecipes to reduction recipes.
+  if (!VPlanTransforms::runPass(VPlanTransforms::legalizeUnclassifiedPhis,
+                                *Plan))
+    return nullptr;
   // Apply mandatory transformation to handle FP maxnum/minnum reduction with
   // NaNs if possible, bail out otherwise.
   if (!VPlanTransforms::runPass(VPlanTransforms::handleMaxMinNumReductions,
@@ -9317,6 +9332,7 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
       PhiR->setOperand(0, StartV);
     }
   }
+
   for (VPRecipeBase *R : ToDelete)
     R->eraseFromParent();
 
diff --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
index a5de5933d5ff1..89d797520100b 100644
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -1896,7 +1896,8 @@ class LLVM_ABI_FOR_TEST VPHeaderPHIRecipe : public VPSingleDefRecipe,
   ~VPHeaderPHIRecipe() override = default;
 
   /// Method to support type inquiry through isa, cast, and dyn_cast.
-  static inline bool classof(const VPRecipeBase *B) {
+  static inline bool classof(const VPUser *U) {
+    auto *B = cast<VPRecipeBase>(U);
     return B->getVPDefID() >= VPDef::VPFirstHeaderPHISC &&
            B->getVPDefID() <= VPDef::VPLastHeaderPHISC;
   }
@@ -1905,6 +1906,10 @@ class LLVM_ABI_FOR_TEST VPHeaderPHIRecipe : public VPSingleDefRecipe,
     return B && B->getVPDefID() >= VPRecipeBase::VPFirstHeaderPHISC &&
            B->getVPDefID() <= VPRecipeBase::VPLastHeaderPHISC;
   }
+  static inline bool classof(const VPSingleDefRecipe *B) {
+    return B->getVPDefID() >= VPDef::VPFirstHeaderPHISC &&
+           B->getVPDefID() <= VPDef::VPLastHeaderPHISC;
+  }
 
   /// Generate the phi nodes.
   void execute(VPTransformState &State) override = 0;
@@ -1966,7 +1971,7 @@ class VPWidenInductionRecipe : public VPHeaderPHIRecipe {
     return R && classof(R);
   }
 
-  static inline bool classof(const VPHeaderPHIRecipe *R) {
+  static inline bool classof(const VPSingleDefRecipe *R) {
     return classof(static_cast<const VPRecipeBase *>(R));
   }
 
diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index 6c1f53b4eaa24..ad67b107562ae 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -815,3 +815,148 @@ bool VPlanTransforms::handleMaxMinNumReductions(VPlan &Plan) {
   MiddleTerm->setOperand(0, NewCond);
   return true;
 }
+
+bool VPlanTransforms::legalizeUnclassifiedPhis(VPlan &Plan) {
+  using namespace VPlanPatternMatch;
+  for (auto &PhiR : make_early_inc_range(
+           Plan.getVectorLoopRegion()->getEntryBasicBlock()->phis())) {
+    if (!isa<VPWidenPHIRecipe>(&PhiR))
+      continue;
+
+    // Check if PhiR is a min/max reduction that has a user inside the loop
+    // outside the min/max reduction chain. The other user must be the compare
+    // of a FindLastIV reduction chain.
+    auto *MinMaxPhiR = cast<VPWidenPHIRecipe>(&PhiR);
+    auto *MinMaxOp = dyn_cast_or_null<VPSingleDefRecipe>(
+        MinMaxPhiR->getOperand(1)->getDefiningRecipe());
+    if (!MinMaxOp)
+      return false;
+
+    // The incoming value must be a min/max instrinsic.
+    // TODO: Also handle the select variant.
+    Intrinsic::ID ID = Intrinsic::not_intrinsic;
+    if (auto *WideInt = dyn_cast<VPWidenIntrinsicRecipe>(MinMaxOp))
+      ID = WideInt->getVectorIntrinsicID();
+    else {
+      auto *RepR = dyn_cast<VPReplicateRecipe>(MinMaxOp);
+      if (!RepR || !isa<IntrinsicInst>(RepR->getUnderlyingInstr()))
+        return false;
+      ID = cast<IntrinsicInst>(RepR->getUnderlyingInstr())->getIntrinsicID();
+    }
+    RecurKind RdxKind = RecurKind::None;
+    switch (ID) {
+    case Intrinsic::umax:
+      RdxKind = RecurKind::UMax;
+      break;
+    case Intrinsic::umin:
+      RdxKind = RecurKind::UMin;
+      break;
+    case Intrinsic::smax:
+      RdxKind = RecurKind::SMax;
+      break;
+    case Intrinsic::smin:
+      RdxKind = RecurKind::SMin;
+      break;
+    default:
+      return false;
+    }
+
+    // The min/max intrinsic must use the phi and itself must only be used by
+    // the phi and a resume-phi in the scalar preheader.
+    if (MinMaxOp->getOperand(0) != MinMaxPhiR &&
+        MinMaxOp->getOperand(1) != MinMaxPhiR)
+      return false;
+    if (MinMaxPhiR->getNumUsers() != 2 ||
+        any_of(MinMaxOp->users(), [MinMaxPhiR, &Plan](VPUser *U) {
+          auto *Phi = dyn_cast<VPPhi>(U);
+          return MinMaxPhiR != U &&
+                 (!Phi || Phi->getParent() != Plan.getScalarPreheader());
+        }))
+      return false;
+
+    // One user of MinMaxPhiR is MinMaxOp, the other users must be a compare
+    // that's part of a FindLastIV chain.
+    auto MinMaxUsers = to_vector(MinMaxPhiR->users());
+    auto *Cmp = dyn_cast<VPRecipeWithIRFlags>(
+        MinMaxUsers[0] == MinMaxOp ? MinMaxUsers[1] : MinMaxUsers[0]);
+    VPValue *CmpOpA;
+    VPValue *CmpOpB;
+    if (!Cmp || Cmp->getNumUsers() != 1 ||
+        !match(Cmp, m_Binary<Instruction::ICmp>(m_VPValue(CmpOpA),
+                                                m_VPValue(CmpOpB))))
+      return false;
+
+    // Normalize the predicate so MinMaxPhiR is on the right side.
+    CmpInst::Predicate Pred = Cmp->getPredicate();
+    if (CmpOpA == MinMaxPhiR)
+      Pred = CmpInst::getSwappedPredicate(Pred);
+
+    // Determine if the predicate is not strict.
+    bool IsNonStrictPred = ICmpInst::isLE(Pred) || ICmpInst::isGE(Pred);
+    // Account for a mis-match between RdxKind and the predicate.
+    switch (RdxKind) {
+    case RecurKind::UMin:
+    case RecurKind::SMin:
+      IsNonStrictPred |= ICmpInst::isGT(Pred);
+      break;
+    case RecurKind::UMax:
+    case RecurKind::SMax:
+      IsNonStrictPred |= ICmpInst::isLT(Pred);
+      break;
+    default:
+      llvm_unreachable("unsupported kind");
+    }
+
+    // TODO: Strict predicates need to find the first IV value for which the
+    // predicate holds, not the last.
+    if (Pred == CmpInst::ICMP_NE || !IsNonStrictPred)
+      return false;
+
+    // Cmp must be used by the select of a FindLastIV chain.
+    VPValue *Sel = dyn_cast<VPSingleDefRecipe>(*Cmp->user_begin());
+    VPValue *IVOp, *FindIV;
+    if (!Sel ||
+        !match(Sel,
+               m_Select(m_Specific(Cmp), m_VPValue(IVOp), m_VPValue(FindIV))) ||
+        Sel->getNumUsers() != 2 || !isa<VPWidenIntOrFpInductionRecipe>(IVOp))
+      return false;
+    auto *FindIVPhiR = dyn_cast<VPReductionPHIRecipe>(FindIV);
+    if (!FindIVPhiR || !RecurrenceDescriptor::isFindLastIVRecurrenceKind(
+                           FindIVPhiR->getRecurrenceKind()))
+      return false;
+
+    assert(!FindIVPhiR->isInLoop() && !FindIVPhiR->isOrdered() &&
+           "cannot handle inloop/ordered reductions yet");
+
+    auto NewPhiR = new VPReductionPHIRecipe(
+        cast<PHINode>(MinMaxPhiR->getUnderlyingInstr()), RdxKind,
+        *MinMaxPhiR->getOperand(0), false, false, 1);
+    NewPhiR->insertBefore(MinMaxPhiR);
+    MinMaxPhiR->replaceAllUsesWith(NewPhiR);
+    NewPhiR->addOperand(MinMaxPhiR->getOperand(1));
+    MinMaxPhiR->eraseFromParent();
+
+    // The reduction using MinMaxPhiR needs adjusting to compute the correct
+    // result:
+    //  1. We need to find the last IV for which the condition based on the
+    //  min/max recurrence is true,
+    //  2. Compare the partial min/max reduction result to its final value and,
+    //  3. Select the lanes of the partial FindLastIV reductions which
+    //  correspond to the lanes matching the min/max reduction result.
+    VPInstruction *FindIVResult = cast<VPInstruction>(
+        *(Sel->user_begin() + (*Sel->user_begin() == FindIVPhiR ? 1 : 0)));
+    VPBuilder B(FindIVResult);
+    VPInstruction *MinMaxResult =
+        B.createNaryOp(VPInstruction::ComputeReductionResult,
+                       {NewPhiR, NewPhiR->getBackedgeValue()}, VPIRFlags(), {});
+    NewPhiR->getBackedgeValue()->replaceUsesWithIf(
+        MinMaxResult, [](VPUser &U, unsigned) { return isa<VPPhi>(&U); });
+    auto *FinalMinMaxCmp = B.createICmp(
+        CmpInst::ICMP_EQ, MinMaxResult->getOperand(1), MinMaxResult);
+    auto *FinalIVSelect =
+        B.createSelect(FinalMinMaxCmp, FindIVResult->getOperand(3),
+                       FindIVResult->getOperand(2));
+    FindIVResult->setOperand(3, FinalIVSelect);
+  }
+  return true;
+}
diff --git a/llvm/lib/Transforms/Vectorize/VPlanTransforms.h b/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
index 880159f760922..35f6447715bc7 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
+++ b/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
@@ -93,6 +93,11 @@ struct VPlanTransforms {
           GetIntOrFpInductionDescriptor,
       ScalarEvolution &SE, const TargetLibraryInfo &TLI);
 
+  /// Try to legalize unclassified phis by converting VPWidenPHIRecipes to
+  /// min-max reductions used by FindLastIV reductions if possible. Returns
+  /// false if the VPlan contains VPWidenPHIRecipes that cannot be legalized.
+  static bool legalizeUnclassifiedPhis(VPlan &Plan);
+
   /// Try to have all users of fixed-order recurrences appear after the recipe
   /// defining their previous value, by either sinking users or hoisting recipes
   /// defining their previous value (and its operands). Then introduce
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
index cc7b9e26ca256..05a79678a4de9 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
@@ -47,21 +47,69 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp uge <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp uge <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[VEC_PHI2]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[VEC_PHI3]], <2 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <2 x i1> [[TMP4]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <2 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <2 x i1> [[TMP12]], <2 x i64> [[TMP8]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP13]], <2 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -131,21 +179,69 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sge <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp sge <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[VEC_PHI2]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[VEC_PHI3]], <2 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <2 x i1> [[TMP4]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smin.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <2 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <2 x i1> [[TMP12]], <2 x i64> [[TMP8]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP13]], <2 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -215,21 +311,69 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ule <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp ule <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[VEC_PHI2]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[VEC_PHI3]], <2 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <2 x i1> [[TMP4]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <2 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <2 x i1> [[TMP12]], <2 x i64> [[TMP8]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP13]], <2 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -299,21 +443,69 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sle <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp sle <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[VEC_PHI2]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[VEC_PHI3]], <2 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <2 x i1> [[TMP4]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <2 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <2 x i1> [[TMP12]], <2 x i64> [[TMP8]], <2 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP13]], <2 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
diff --git a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
index 6b44586286c7b..9298cf24013b1 100644
--- a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
@@ -47,21 +47,69 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 8
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp uge <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp uge <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI3]], <4 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <4 x i1> [[TMP4]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <4 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <4 x i1> [[TMP12]], <4 x i64> [[TMP8]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP13]], <4 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -131,21 +179,69 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 8
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sge <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp sge <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI3]], <4 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <4 x i1> [[TMP4]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <4 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <4 x i1> [[TMP12]], <4 x i64> [[TMP8]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP13]], <4 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -215,21 +311,69 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 8
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ule <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp ule <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI3]], <4 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <4 x i1> [[TMP4]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <4 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <4 x i1> [[TMP12]], <4 x i64> [[TMP8]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP13]], <4 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -299,21 +443,69 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_last_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 8
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sle <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp sle <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP6]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI3]], <4 x i64> [[WIDE_LOAD4]])
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP8]] = select <4 x i1> [[TMP4]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP10]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq <4 x i64> [[TMP6]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP14:%.*]] = select <4 x i1> [[TMP12]], <4 x i64> [[TMP8]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[RDX_MINMAX5:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP13]], <4 x i64> [[TMP14]])
+; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
diff --git a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
index 48d2eee600151..a1a825fbc473e 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
@@ -5,21 +5,57 @@ define i64 @test_vectorize_select_smax_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -47,21 +83,57 @@ define i64 @test_vectorize_select_smax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_idx_cond_flipped(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -219,21 +291,57 @@ define i64 @test_vectorize_select_smax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_idx_min_ops_switched(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[L]], i64 [[MIN_VAL]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -303,21 +411,59 @@ define i64 @test_cmp_and_smax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-LABEL: define i64 @test_cmp_and_smax_use_different_values(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[X:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[X]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT2:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT3:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT2]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT3]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX4]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[X]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
diff --git a/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
index bca6bf38da8d9..d9d241213ba4f 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
@@ -7,21 +7,57 @@ define i64 @test_vectorize_select_smin_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -49,21 +85,57 @@ define i64 @test_vectorize_select_smin_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_idx_cond_flipped(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -93,15 +165,15 @@ define i64 @test_vectorize_select_smin_idx_select_ops_flipped(ptr %src, i64 %n)
 ; CHECK-NEXT:  [[ENTRY:.*]]:
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[MIN_IDX]], i64 [[IV]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[MIN_IDX]], i64 [[IV1]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
 ; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
 ; CHECK:       [[EXIT]]:
@@ -221,21 +293,57 @@ define i64 @test_vectorize_select_smin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_idx_min_ops_switched(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[L]], i64 [[MIN_VAL]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -305,21 +413,59 @@ define i64 @test_cmp_and_smin_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-LABEL: define i64 @test_cmp_and_smin_use_different_values(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[X:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[X]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT2:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT3:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT2]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT3]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX4]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[X]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
diff --git a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
index cabb868a1dbe5..696264238a860 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
@@ -5,21 +5,57 @@ define i64 @test_vectorize_select_umax_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -47,21 +83,57 @@ define i64 @test_vectorize_select_umax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_idx_cond_flipped(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -219,21 +291,57 @@ define i64 @test_vectorize_select_umax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_idx_min_ops_switched(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[L]], i64 [[MIN_VAL]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -303,21 +411,59 @@ define i64 @test_cmp_and_umax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-LABEL: define i64 @test_cmp_and_umax_use_different_values(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[X:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[X]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT2:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT3:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT2]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT3]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MAX_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MAX_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX4]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[X]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umax.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MAX_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
diff --git a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
index 549ee0167f2f2..9d36af3216520 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
@@ -7,21 +7,57 @@ define i64 @test_vectorize_select_umin_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_idx(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -49,21 +85,57 @@ define i64 @test_vectorize_select_umin_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_idx_cond_flipped(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -93,15 +165,15 @@ define i64 @test_vectorize_select_umin_idx_select_ops_flipped(ptr %src, i64 %n)
 ; CHECK-NEXT:  [[ENTRY:.*]]:
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[MIN_IDX]], i64 [[IV]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[MIN_IDX]], i64 [[IV1]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
 ; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
 ; CHECK:       [[EXIT]]:
@@ -221,21 +293,57 @@ define i64 @test_vectorize_select_umin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_idx_min_ops_switched(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[L]], i64 [[MIN_VAL]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -305,21 +413,59 @@ define i64 @test_cmp_and_umin_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-LABEL: define i64 @test_cmp_and_umin_use_different_values(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[X:%.*]], i64 [[N:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], 4
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[X]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT2:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT3:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT2]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT3]]
+; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX4]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[X]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
 ;
 entry:
@@ -553,5 +699,49 @@ exit:
   ret i64 %res
 }
 
+define i64 @test_cmp_use_find_iv_phi_twice(ptr %src, i64 %n) {
+; CHECK-LABEL: define i64 @test_cmp_use_find_iv_phi_twice(
+; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[LOOP:.*]]
+; CHECK:       [[LOOP]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[ADD:%.*]] = add i64 [[MIN_VAL]], [[L]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[ADD]]
+; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
+; CHECK-NEXT:    ret i64 [[RES]]
+;
+entry:
+  br label %loop
+
+loop:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
+  %min.idx = phi i64 [ 0, %entry ], [ %min.idx.next, %loop ]
+  %min.val = phi i64 [ 0, %entry ], [ %min.val.next, %loop ]
+  %gep = getelementptr i64, ptr %src, i64 %iv
+  %l = load i64, ptr %gep
+  %add = add i64 %min.val, %l
+  %cmp = icmp uge i64 %min.val, %add
+  %min.val.next = tail call i64 @llvm.umin.i64(i64 %min.val, i64 %l)
+  %min.idx.next = select i1 %cmp, i64 %iv, i64 %min.idx
+  %iv.next = add nuw nsw i64 %iv, 1
+  %exitcond.not = icmp eq i64 %iv.next, %n
+  br i1 %exitcond.not, label %exit, label %loop
+
+exit:
+  %res = phi i64 [ %min.idx.next, %loop ]
+  ret i64 %res
+}
+
 declare i64 @llvm.umin.i64(i64, i64)
 declare i16 @llvm.umin.i16(i16, i16)

>From 2688d03e11f51fed359fa6616fa0ed218c023692 Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Tue, 22 Jul 2025 15:00:24 +0100
Subject: [PATCH 2/5] !fixup address review comments, thanks

---
 llvm/lib/Transforms/Vectorize/LoopVectorize.cpp      |  6 +++---
 llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp  |  4 ++--
 .../Transforms/LoopVectorize/AArch64/select-index.ll | 12 ++++--------
 .../LoopVectorize/select-index-interleaving.ll       | 12 ++++--------
 .../LoopVectorize/select-smax-last-index.ll          | 12 ++++--------
 .../LoopVectorize/select-smin-last-index.ll          | 12 ++++--------
 .../LoopVectorize/select-umax-last-index.ll          | 12 ++++--------
 .../LoopVectorize/select-umin-last-index.ll          | 12 ++++--------
 8 files changed, 29 insertions(+), 53 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index cfd09dce3e6a4..ef0d6ec3ee04d 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -7263,9 +7263,9 @@ static void fixReductionScalarResumeWhenVectorizingEpilog(
          ((CmpOp == StartV && isGuaranteedNotToBeUndefOrPoison(CmpOp))));
     assert(IsExpectedPattern && "Unexpected reduction resume pattern");
     MainResumeValue = OrigResumeV;
-  } else {
-    if (auto *VPI = dyn_cast<VPInstruction>(EpiRedHeaderPhi->getStartValue()))
-      MainResumeValue = VPI->getOperand(0)->getUnderlyingValue();
+  } else if (auto *VPI =
+                 dyn_cast<VPInstruction>(EpiRedHeaderPhi->getStartValue())) {
+    MainResumeValue = VPI->getOperand(0)->getUnderlyingValue();
   }
 
   PHINode *MainResumePhi = cast<PHINode>(MainResumeValue);
diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index ad67b107562ae..6a8c5daa99245 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -835,9 +835,9 @@ bool VPlanTransforms::legalizeUnclassifiedPhis(VPlan &Plan) {
     // The incoming value must be a min/max instrinsic.
     // TODO: Also handle the select variant.
     Intrinsic::ID ID = Intrinsic::not_intrinsic;
-    if (auto *WideInt = dyn_cast<VPWidenIntrinsicRecipe>(MinMaxOp))
+    if (auto *WideInt = dyn_cast<VPWidenIntrinsicRecipe>(MinMaxOp)) {
       ID = WideInt->getVectorIntrinsicID();
-    else {
+    } else {
       auto *RepR = dyn_cast<VPReplicateRecipe>(MinMaxOp);
       if (!RepR || !isa<IntrinsicInst>(RepR->getUnderlyingInstr()))
         return false;
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
index 05a79678a4de9..09302a310a397 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
@@ -62,9 +62,8 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp uge <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp uge <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -194,9 +193,8 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp sge <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp sge <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -326,9 +324,8 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp ule <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp ule <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -458,9 +455,8 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 2
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <2 x i64>, ptr [[TMP2]], align 8
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp sle <2 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp sle <2 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
index 9298cf24013b1..2ce99341b5215 100644
--- a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
@@ -62,9 +62,8 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp uge <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp uge <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -194,9 +193,8 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp sge <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp sge <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -326,9 +324,8 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp ule <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp ule <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
@@ -458,9 +455,8 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i64, ptr [[GEP]], i32 4
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i64>, ptr [[TMP2]], align 4
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp sle <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp sle <4 x i64> [[VEC_PHI3]], [[WIDE_LOAD4]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
index a1a825fbc473e..3d36133b8cd9d 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
@@ -17,8 +17,7 @@ define i64 @test_vectorize_select_smax_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -95,8 +94,7 @@ define i64 @test_vectorize_select_smax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -303,8 +301,7 @@ define i64 @test_vectorize_select_smax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -425,8 +422,7 @@ define i64 @test_cmp_and_smax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
index d9d241213ba4f..6a43810ffb051 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smin-last-index.ll
@@ -19,8 +19,7 @@ define i64 @test_vectorize_select_smin_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -97,8 +96,7 @@ define i64 @test_vectorize_select_smin_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sle <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -305,8 +303,7 @@ define i64 @test_vectorize_select_smin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -427,8 +424,7 @@ define i64 @test_cmp_and_smin_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sge <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
index 696264238a860..2b7bec09b9eb0 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
@@ -17,8 +17,7 @@ define i64 @test_vectorize_select_umax_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -95,8 +94,7 @@ define i64 @test_vectorize_select_umax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -303,8 +301,7 @@ define i64 @test_vectorize_select_umax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -425,8 +422,7 @@ define i64 @test_cmp_and_umax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
index 9d36af3216520..2970f02b5c800 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
@@ -19,8 +19,7 @@ define i64 @test_vectorize_select_umin_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -97,8 +96,7 @@ define i64 @test_vectorize_select_umin_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -305,8 +303,7 @@ define i64 @test_vectorize_select_umin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
@@ -427,8 +424,7 @@ define i64 @test_cmp_and_umin_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i32 0
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[BROADCAST_SPLAT]]
 ; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]

>From 26ebf5aa93bc987674469109bcbbee3d838f1e32 Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Fri, 1 Aug 2025 11:54:42 +0100
Subject: [PATCH 3/5] !fixup remove stray new line

---
 llvm/lib/Transforms/Vectorize/LoopVectorize.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index ef0d6ec3ee04d..4d6ba39997a5c 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -9332,7 +9332,6 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
       PhiR->setOperand(0, StartV);
     }
   }
-
   for (VPRecipeBase *R : ToDelete)
     R->eraseFromParent();
 

>From 2871d6cd0aecf62b475712cdca7bc3b8895e2233 Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Thu, 11 Sep 2025 19:15:33 +0100
Subject: [PATCH 4/5] !fixup fix build after merge

---
 .../Vectorize/LoopVectorizationLegality.cpp    | 18 ++++++++++++++++--
 .../lib/Transforms/Vectorize/LoopVectorize.cpp |  3 ++-
 .../Transforms/Vectorize/VPlanConstruction.cpp |  4 ++--
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
index 55aa099b713fc..3abc8e4b496a4 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
@@ -801,7 +801,6 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
   // For each block in the loop.
   for (BasicBlock *BB : TheLoop->blocks()) {
     // Scan the instructions in the block and look for hazards.
-    PHINode *UnclassifiedPhi = nullptr;
     for (Instruction &I : *BB) {
       Result &= canVectorizeInstr(I);
       if (!DoExtraAnalysis && !Result)
@@ -809,7 +808,22 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
     }
   }
 
-  if (size(TheLoop->getHeader()->phis()):
+  if (range_size(TheLoop->getHeader()->phis()) != FixedOrderRecurrences.size() +
+                                                      Inductions.size() +
+                                                      Reductions.size() &&
+      none_of(TheLoop->getHeader()->phis(), [this](PHINode &P) {
+        auto I = Reductions.find(&P);
+        return I != Reductions.end() &&
+               RecurrenceDescriptor::isFindLastIVRecurrenceKind(
+                   I->second.getRecurrenceKind());
+      })) {
+    reportVectorizationFailure("Found an unidentified PHI",
+                               "value that could not be identified as "
+                               "reduction is used outside the loop",
+                               "NonReductionValueUsedOutsideLoop", ORE, TheLoop,
+                               &*TheLoop->getHeader()->phis().begin());
+    return false;
+  }
 
   if (!PrimaryInduction) {
     if (Inductions.empty()) {
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 7cd5702b49e5f..fe71baa3bb158 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8593,9 +8593,10 @@ VPlanPtr LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(
       VPRecipeBase *Recipe =
           RecipeBuilder.tryToCreateWidenRecipe(SingleDef, Range);
       if (!Recipe) {
-        if (isa<VPWidenPHIRecipe>(SingleDef))
+        if (isa<VPPhi>(SingleDef))
           continue;
         Recipe = RecipeBuilder.handleReplication(Instr, R.operands(), Range);
+      }
 
       RecipeBuilder.setRecipe(Instr, Recipe);
       if (isa<VPWidenIntOrFpInductionRecipe>(Recipe) && isa<TruncInst>(Instr)) {
diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index 74c1e67b5e8e6..d692e07ea59c5 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -920,13 +920,13 @@ bool VPlanTransforms::legalizeUnclassifiedPhis(VPlan &Plan) {
   using namespace VPlanPatternMatch;
   for (auto &PhiR : make_early_inc_range(
            Plan.getVectorLoopRegion()->getEntryBasicBlock()->phis())) {
-    if (!isa<VPWidenPHIRecipe>(&PhiR))
+    if (!isa<VPPhi>(&PhiR))
       continue;
 
     // Check if PhiR is a min/max reduction that has a user inside the loop
     // outside the min/max reduction chain. The other user must be the compare
     // of a FindLastIV reduction chain.
-    auto *MinMaxPhiR = cast<VPWidenPHIRecipe>(&PhiR);
+    auto *MinMaxPhiR = cast<VPPhi>(&PhiR);
     auto *MinMaxOp = dyn_cast_or_null<VPSingleDefRecipe>(
         MinMaxPhiR->getOperand(1)->getDefiningRecipe());
     if (!MinMaxOp)

>From 98fb1f7d20bd372fa6d733c7f2a75d08c88be46a Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Thu, 11 Sep 2025 22:05:58 +0100
Subject: [PATCH 5/5] !fixup detect multi-use min/max recurrences.

---
 llvm/include/llvm/Analysis/IVDescriptors.h    | 24 +++++++-
 llvm/lib/Analysis/IVDescriptors.cpp           | 39 ++++++++++++
 .../Vectorize/LoopVectorizationLegality.cpp   | 26 +++-----
 .../Transforms/Vectorize/LoopVectorize.cpp    |  3 +
 .../Vectorize/VPlanConstruction.cpp           | 59 +++----------------
 .../LoopVectorize/AArch64/select-index.ll     | 24 +++++---
 .../select-index-interleaving.ll              | 24 +++++---
 .../LoopVectorize/select-smax-last-index.ll   | 12 ++--
 .../LoopVectorize/select-umax-last-index.ll   | 12 ++--
 .../LoopVectorize/select-umin-last-index.ll   | 58 +++++++++---------
 10 files changed, 159 insertions(+), 122 deletions(-)

diff --git a/llvm/include/llvm/Analysis/IVDescriptors.h b/llvm/include/llvm/Analysis/IVDescriptors.h
index f9e6da6d0846a..e183db5349d96 100644
--- a/llvm/include/llvm/Analysis/IVDescriptors.h
+++ b/llvm/include/llvm/Analysis/IVDescriptors.h
@@ -42,9 +42,13 @@ enum class RecurKind {
   And,      ///< Bitwise or logical AND of integers.
   Xor,      ///< Bitwise or logical XOR of integers.
   SMin,     ///< Signed integer min implemented in terms of select(cmp()).
+  SMinMultiUse,     ///< Signed integer min implemented in terms of select(cmp()).
   SMax,     ///< Signed integer max implemented in terms of select(cmp()).
+  SMaxMultiUse,     ///< Signed integer max implemented in terms of select(cmp()).
   UMin,     ///< Unsigned integer min implemented in terms of select(cmp()).
+  UMinMultiUse,     ///< Unsigned integer min implemented in terms of select(cmp()).
   UMax,     ///< Unsigned integer max implemented in terms of select(cmp()).
+  UMaxMultiUse,     ///< Unsigned integer max implemented in terms of select(cmp()).
   FAdd,     ///< Sum of floats.
   FMul,     ///< Product of floats.
   FMin,     ///< FP min implemented in terms of select(cmp()).
@@ -247,8 +251,24 @@ class RecurrenceDescriptor {
 
   /// Returns true if the recurrence kind is an integer min/max kind.
   static bool isIntMinMaxRecurrenceKind(RecurKind Kind) {
-    return Kind == RecurKind::UMin || Kind == RecurKind::UMax ||
-           Kind == RecurKind::SMin || Kind == RecurKind::SMax;
+    return Kind == RecurKind::UMin || Kind == RecurKind::UMinMultiUse ||
+           Kind == RecurKind::UMax || Kind == RecurKind::UMaxMultiUse ||
+           Kind == RecurKind::SMin || Kind == RecurKind::SMinMultiUse ||
+           Kind == RecurKind::SMax || Kind == RecurKind::SMaxMultiUse;
+  }
+
+  static RecurKind convertFromMultiUseKind(RecurKind Kind) {
+    switch (Kind) {
+    case RecurKind::UMaxMultiUse:
+      return RecurKind::UMax;
+    case RecurKind::UMinMultiUse:
+      return RecurKind::UMin;
+    case RecurKind::SMinMultiUse:
+      return RecurKind::SMin;
+    case RecurKind::SMaxMultiUse:
+      return RecurKind::SMax;
+    }
+    return Kind;
   }
 
   /// Returns true if the recurrence kind is a floating-point min/max kind.
diff --git a/llvm/lib/Analysis/IVDescriptors.cpp b/llvm/lib/Analysis/IVDescriptors.cpp
index b8c540ce4b99d..ade2871a6c281 100644
--- a/llvm/lib/Analysis/IVDescriptors.cpp
+++ b/llvm/lib/Analysis/IVDescriptors.cpp
@@ -214,6 +214,41 @@ static bool checkOrderedReduction(RecurKind Kind, Instruction *ExactFPMathInst,
   return true;
 }
 
+static std::optional<RecurrenceDescriptor>
+getMultiUseMinMax(PHINode *Phi, RecurKind Kind, Loop *TheLoop) {
+  BasicBlock *Latch = TheLoop->getLoopLatch();
+  if (!Latch)
+    return std::nullopt;
+  Value *Inc = Phi->getIncomingValueForBlock(Latch);
+  RecurKind RK;
+  if (Phi->hasOneUse() ||
+      !RecurrenceDescriptor::isIntMinMaxRecurrenceKind(Kind))
+    return std::nullopt;
+
+  Value *A, *B;
+  if (match(Inc, m_OneUse(m_UMin(m_Value(A), m_Value(B)))))
+    RK = RecurKind::UMinMultiUse;
+  else if (match(Inc, m_OneUse(m_UMax(m_Value(A), m_Value(B)))))
+    RK = RecurKind::UMaxMultiUse;
+  else if (match(Inc, m_OneUse(m_SMax(m_Value(A), m_Value(B)))))
+    RK = RecurKind::SMaxMultiUse;
+  else if (match(Inc, m_OneUse(m_SMin(m_Value(A), m_Value(B)))))
+    RK = RecurKind::SMinMultiUse;
+  else
+    return std::nullopt;
+
+  if (RecurrenceDescriptor::convertFromMultiUseKind(RK) != Kind || A == B ||
+      (A != Phi && B != Phi))
+    return std::nullopt;
+
+  SmallPtrSet<Instruction *, 4> CastInsts;
+  Value *RdxStart = Phi->getIncomingValueForBlock(TheLoop->getLoopPreheader());
+  RecurrenceDescriptor RD(RdxStart, nullptr, nullptr, RK, FastMathFlags(),
+                          nullptr, Phi->getType(), false, false, CastInsts,
+                          -1U);
+  return {RD};
+}
+
 bool RecurrenceDescriptor::AddReductionVar(
     PHINode *Phi, RecurKind Kind, Loop *TheLoop, FastMathFlags FuncFMF,
     RecurrenceDescriptor &RedDes, DemandedBits *DB, AssumptionCache *AC,
@@ -225,6 +260,10 @@ bool RecurrenceDescriptor::AddReductionVar(
   if (Phi->getParent() != TheLoop->getHeader())
     return false;
 
+  if (auto RD = getMultiUseMinMax(Phi, Kind, TheLoop)) {
+    RedDes = *RD;
+    return true;
+  }
   // Obtain the reduction start value from the value that comes from the loop
   // preheader.
   Value *RdxStart = Phi->getIncomingValueForBlock(TheLoop->getLoopPreheader());
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
index 3abc8e4b496a4..85a6fcaf3ecdd 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
@@ -808,23 +808,6 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
     }
   }
 
-  if (range_size(TheLoop->getHeader()->phis()) != FixedOrderRecurrences.size() +
-                                                      Inductions.size() +
-                                                      Reductions.size() &&
-      none_of(TheLoop->getHeader()->phis(), [this](PHINode &P) {
-        auto I = Reductions.find(&P);
-        return I != Reductions.end() &&
-               RecurrenceDescriptor::isFindLastIVRecurrenceKind(
-                   I->second.getRecurrenceKind());
-      })) {
-    reportVectorizationFailure("Found an unidentified PHI",
-                               "value that could not be identified as "
-                               "reduction is used outside the loop",
-                               "NonReductionValueUsedOutsideLoop", ORE, TheLoop,
-                               &*TheLoop->getHeader()->phis().begin());
-    return false;
-  }
-
   if (!PrimaryInduction) {
     if (Inductions.empty()) {
       reportVectorizationFailure(
@@ -944,8 +927,15 @@ bool LoopVectorizationLegality::canVectorizeInstr(Instruction &I) {
     if (InductionDescriptor::isInductionPHI(Phi, TheLoop, PSE, ID, true) &&
         !IsDisallowedStridedPointerInduction(ID)) {
       addInductionPhi(Phi, ID, AllowedExit);
+      return true;
     }
-    return true;
+
+    reportVectorizationFailure("Found an unidentified PHI",
+                               "value that could not be identified as "
+                               "reduction is used outside the loop",
+                               "NonReductionValueUsedOutsideLoop", ORE, TheLoop,
+                               Phi);
+    return false;
   } // end of PHI handling
 
   // We handle calls that:
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index fe71baa3bb158..567f963648b56 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -7929,6 +7929,9 @@ void VPRecipeBuilder::collectScaledReductions(VFRange &Range) {
   SmallVector<std::pair<PartialReductionChain, unsigned>>
       PartialReductionChains;
   for (const auto &[Phi, RdxDesc] : Legal->getReductionVars()) {
+    if (RecurrenceDescriptor::isMinMaxRecurrenceKind(
+            RdxDesc.getRecurrenceKind()))
+      continue;
     getScaledReductions(Phi, RdxDesc.getLoopExitInstr(), Range,
                         PartialReductionChains);
   }
diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index d692e07ea59c5..f5fa461d1214b 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -920,62 +920,19 @@ bool VPlanTransforms::legalizeUnclassifiedPhis(VPlan &Plan) {
   using namespace VPlanPatternMatch;
   for (auto &PhiR : make_early_inc_range(
            Plan.getVectorLoopRegion()->getEntryBasicBlock()->phis())) {
-    if (!isa<VPPhi>(&PhiR))
+    auto *MinMaxPhiR = dyn_cast<VPReductionPHIRecipe>(&PhiR);
+    if (!MinMaxPhiR || !RecurrenceDescriptor::isIntMinMaxRecurrenceKind(
+                           MinMaxPhiR->getRecurrenceKind()))
       continue;
 
-    // Check if PhiR is a min/max reduction that has a user inside the loop
-    // outside the min/max reduction chain. The other user must be the compare
-    // of a FindLastIV reduction chain.
-    auto *MinMaxPhiR = cast<VPPhi>(&PhiR);
-    auto *MinMaxOp = dyn_cast_or_null<VPSingleDefRecipe>(
-        MinMaxPhiR->getOperand(1)->getDefiningRecipe());
-    if (!MinMaxOp)
-      return false;
-
-    // The incoming value must be a min/max instrinsic.
-    // TODO: Also handle the select variant.
-    Intrinsic::ID ID = Intrinsic::not_intrinsic;
-    if (auto *WideInt = dyn_cast<VPWidenIntrinsicRecipe>(MinMaxOp)) {
-      ID = WideInt->getVectorIntrinsicID();
-    } else {
-      auto *RepR = dyn_cast<VPReplicateRecipe>(MinMaxOp);
-      if (!RepR || !isa<IntrinsicInst>(RepR->getUnderlyingInstr()))
-        return false;
-      ID = cast<IntrinsicInst>(RepR->getUnderlyingInstr())->getIntrinsicID();
-    }
-    RecurKind RdxKind = RecurKind::None;
-    switch (ID) {
-    case Intrinsic::umax:
-      RdxKind = RecurKind::UMax;
-      break;
-    case Intrinsic::umin:
-      RdxKind = RecurKind::UMin;
-      break;
-    case Intrinsic::smax:
-      RdxKind = RecurKind::SMax;
-      break;
-    case Intrinsic::smin:
-      RdxKind = RecurKind::SMin;
-      break;
-    default:
-      return false;
-    }
-
-    // The min/max intrinsic must use the phi and itself must only be used by
-    // the phi and a resume-phi in the scalar preheader.
-    if (MinMaxOp->getOperand(0) != MinMaxPhiR &&
-        MinMaxOp->getOperand(1) != MinMaxPhiR)
-      return false;
-    if (MinMaxPhiR->getNumUsers() != 2 ||
-        any_of(MinMaxOp->users(), [MinMaxPhiR, &Plan](VPUser *U) {
-          auto *Phi = dyn_cast<VPPhi>(U);
-          return MinMaxPhiR != U &&
-                 (!Phi || Phi->getParent() != Plan.getScalarPreheader());
-        }))
-      return false;
+    RecurKind RdxKind = RecurrenceDescriptor::convertFromMultiUseKind(
+        MinMaxPhiR->getRecurrenceKind());
+    if (RdxKind == MinMaxPhiR->getRecurrenceKind())
+      continue;
 
     // One user of MinMaxPhiR is MinMaxOp, the other users must be a compare
     // that's part of a FindLastIV chain.
+    auto *MinMaxOp = cast<VPRecipeWithIRFlags>(MinMaxPhiR->getBackedgeValue());
     auto MinMaxUsers = to_vector(MinMaxPhiR->users());
     auto *Cmp = dyn_cast<VPRecipeWithIRFlags>(
         MinMaxUsers[0] == MinMaxOp ? MinMaxUsers[1] : MinMaxUsers[0]);
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
index 09302a310a397..644a332918954 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
@@ -88,17 +88,19 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
@@ -219,17 +221,19 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.smin.v2i64(<2 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
@@ -350,17 +354,19 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.umax.v2i64(<2 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
@@ -481,17 +487,19 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP5]], <2 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
index 2ce99341b5215..7bc067d3a8abd 100644
--- a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
@@ -88,17 +88,19 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
@@ -219,17 +221,19 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sge i64 [[MIN_VAL]], [[L]]
@@ -350,17 +354,19 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i64 [[MIN_VAL]], [[L]]
@@ -481,17 +487,19 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP15:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX5]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP15]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP15]], i64 0
+; CHECK-NEXT:    [[RDX_MINMAX6:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP5]], <4 x i64> [[TMP6]])
+; CHECK-NEXT:    [[TMP16:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX6]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX7:%.*]] = phi i64 [ [[TMP16]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX7]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sle i64 [[MIN_VAL]], [[L]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
index 3d36133b8cd9d..1dd383d4a17bd 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
@@ -34,12 +34,13 @@ define i64 @test_vectorize_select_smax_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -111,12 +112,13 @@ define i64 @test_vectorize_select_smax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -318,12 +320,13 @@ define i64 @test_vectorize_select_smax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -439,12 +442,13 @@ define i64 @test_cmp_and_smax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
diff --git a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
index 2b7bec09b9eb0..398fc32a5287f 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
@@ -34,12 +34,13 @@ define i64 @test_vectorize_select_umax_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -111,12 +112,13 @@ define i64 @test_vectorize_select_umax_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -318,12 +320,13 @@ define i64 @test_vectorize_select_umax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -439,12 +442,13 @@ define i64 @test_cmp_and_umax_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
diff --git a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
index 2970f02b5c800..a8b9a16f30042 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
@@ -36,12 +36,13 @@ define i64 @test_vectorize_select_umin_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -113,12 +114,13 @@ define i64 @test_vectorize_select_umin_idx_cond_flipped(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
@@ -298,45 +300,46 @@ define i64 @test_vectorize_select_umin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
 ; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
 ; CHECK:       [[VECTOR_BODY]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
-; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
-; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
-; CHECK-NEXT:    [[TMP2:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
-; CHECK-NEXT:    [[TMP3]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
-; CHECK-NEXT:    [[TMP4]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
-; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ splat (i64 -9223372036854775808), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI1]])
+; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
-; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
-; CHECK-NEXT:    br i1 [[TMP5]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
 ; CHECK:       [[MIDDLE_BLOCK]]:
-; CHECK-NEXT:    [[TMP6:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
-; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
+; CHECK-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP2]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP5]], i64 0
 ; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq <4 x i64> [[TMP3]], [[BROADCAST_SPLAT]]
-; CHECK-NEXT:    [[TMP8:%.*]] = select <4 x i1> [[TMP7]], <4 x i64> [[TMP4]], <4 x i64> splat (i64 -9223372036854775808)
-; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
-; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
-; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP6:%.*]] = icmp eq <4 x i64> [[TMP2]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP7:%.*]] = select <4 x i1> [[TMP6]], <4 x i64> [[TMP3]], <4 x i64> splat (i64 -9223372036854775808)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -9223372036854775808
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], i64 0
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP2]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP9]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ [[BC_MERGE_RDX2]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i64 [[MIN_VAL]], [[L]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[L]], i64 [[MIN_VAL]])
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i64 [[IV1]], i64 [[MIN_IDX]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV1]], 1
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
 ; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
@@ -441,12 +444,13 @@ define i64 @test_cmp_and_umin_use_different_values(ptr %src, i64 %x, i64 %n) {
 ; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[TMP8]])
 ; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP9]], -9223372036854775808
 ; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[TMP10:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP3]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i64 [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP6]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX4:%.*]] = phi i64 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]



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