[llvm] [LV] Support argmin/argmax with strict predicates. (PR #170223)

Florian Hahn via llvm-commits llvm-commits at lists.llvm.org
Wed Dec 3 13:16:18 PST 2025


https://github.com/fhahn updated https://github.com/llvm/llvm-project/pull/170223

>From 301e7cbdf39fbcda301b4d3b5de3569337b3153c Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Mon, 1 Dec 2025 21:59:21 +0000
Subject: [PATCH] [LV] Support argmin/argmax with strict predicates.

Extend handleMultiUseReductions to support strict predicates (>, <),
matching the first index instead of the last for non-strict predicates.

For strict predicates is detected, the transformation converts the
FindLastIV reduction to FindFirstIV by:
1. Checking the IV range to ensure it does not include the sentinel value (max).
2. Creating a new reduction with the appropriate FindFirstIV kind
   (FindFirstIVSMin or FindFirstIVUMin based on the IV range)
3. Replacing the old reduction recipe with the new one
---
 llvm/include/llvm/Analysis/IVDescriptors.h    |   6 +
 llvm/lib/Analysis/IVDescriptors.cpp           |  73 ++---
 .../Transforms/Vectorize/LoopVectorize.cpp    |   3 +-
 .../Vectorize/VPlanConstruction.cpp           |  74 ++++-
 .../lib/Transforms/Vectorize/VPlanRecipes.cpp |   1 +
 .../Transforms/Vectorize/VPlanTransforms.h    |   7 +-
 .../LoopVectorize/AArch64/select-index.ll     | 268 +++++++++++++++---
 .../select-index-interleaving.ll              | 244 ++++++++++++++--
 .../LoopVectorize/select-smax-last-index.ll   |  51 +++-
 .../LoopVectorize/select-smin-first-index.ll  | 185 +++++++++---
 .../LoopVectorize/select-umax-last-index.ll   |  51 +++-
 .../LoopVectorize/select-umin-first-index.ll  | 214 +++++++++++---
 .../LoopVectorize/select-umin-last-index.ll   |  18 +-
 .../test/Transforms/LoopVectorize/smax-idx.ll | 167 +++++++++--
 14 files changed, 1115 insertions(+), 247 deletions(-)

diff --git a/llvm/include/llvm/Analysis/IVDescriptors.h b/llvm/include/llvm/Analysis/IVDescriptors.h
index fc141ed6d96fe..2de438ead7f35 100644
--- a/llvm/include/llvm/Analysis/IVDescriptors.h
+++ b/llvm/include/llvm/Analysis/IVDescriptors.h
@@ -28,6 +28,7 @@ class Loop;
 class PredicatedScalarEvolution;
 class ScalarEvolution;
 class SCEV;
+class SCEVAddRecExpr;
 class StoreInst;
 
 /// These are the kinds of recurrences that we support.
@@ -310,6 +311,11 @@ class RecurrenceDescriptor {
            isFindLastIVRecurrenceKind(Kind);
   }
 
+  /// Returns true if \p AR's range is valid for either FindFirstIV or
+  /// FindLastIV reductions i.e. if the sentinel value is outside \p AR's range.
+  static bool isValidIVRangeForFindIV(const SCEVAddRecExpr *AR, bool IsSigned,
+                                      bool IsFindFirstIV, ScalarEvolution &SE);
+
   /// Returns the type of the recurrence. This type can be narrower than the
   /// actual type of the Phi if the recurrence has been type-promoted.
   Type *getRecurrenceType() const { return RecurrenceType; }
diff --git a/llvm/lib/Analysis/IVDescriptors.cpp b/llvm/lib/Analysis/IVDescriptors.cpp
index 7624e0ed6f2b0..add1f27e460d2 100644
--- a/llvm/lib/Analysis/IVDescriptors.cpp
+++ b/llvm/lib/Analysis/IVDescriptors.cpp
@@ -715,6 +715,36 @@ RecurrenceDescriptor::isAnyOfPattern(Loop *Loop, PHINode *OrigPhi,
   return InstDesc(I, RecurKind::AnyOf);
 }
 
+bool RecurrenceDescriptor::isValidIVRangeForFindIV(const SCEVAddRecExpr *AR,
+                                                   bool IsSigned,
+                                                   bool IsFindFirstIV,
+                                                   ScalarEvolution &SE) {
+  const ConstantRange IVRange =
+      IsSigned ? SE.getSignedRange(AR) : SE.getUnsignedRange(AR);
+  unsigned NumBits = AR->getType()->getIntegerBitWidth();
+  ConstantRange ValidRange = ConstantRange::getEmpty(NumBits);
+
+  if (IsFindFirstIV) {
+    if (IsSigned)
+      ValidRange =
+          ConstantRange::getNonEmpty(APInt::getSignedMinValue(NumBits),
+                                     APInt::getSignedMaxValue(NumBits) - 1);
+    else
+      ValidRange = ConstantRange::getNonEmpty(APInt::getMinValue(NumBits),
+                                              APInt::getMaxValue(NumBits) - 1);
+  } else {
+    APInt Sentinel = IsSigned ? APInt::getSignedMinValue(NumBits)
+                              : APInt::getMinValue(NumBits);
+    ValidRange = ConstantRange::getNonEmpty(Sentinel + 1, Sentinel);
+  }
+
+  LLVM_DEBUG(dbgs() << "LV: " << (IsFindFirstIV ? "FindFirstIV" : "FindLastIV")
+                    << " valid range is " << ValidRange << ", and the range of "
+                    << *AR << " is " << IVRange << "\n");
+
+  return ValidRange.contains(IVRange);
+}
+
 // We are looking for loops that do something like this:
 //   int r = 0;
 //   for (int i = 0; i < n; i++) {
@@ -792,49 +822,24 @@ RecurrenceDescriptor::isFindIVPattern(RecurKind Kind, Loop *TheLoop,
     // [Signed|Unsigned]Max(<recurrence type>) for FindFirstIV.
     // TODO: This range restriction can be lifted by adding an additional
     // virtual OR reduction.
-    auto CheckRange = [&](bool IsSigned) {
-      const ConstantRange IVRange =
-          IsSigned ? SE.getSignedRange(AR) : SE.getUnsignedRange(AR);
-      unsigned NumBits = Ty->getIntegerBitWidth();
-      ConstantRange ValidRange = ConstantRange::getEmpty(NumBits);
-      if (isFindLastIVRecurrenceKind(Kind)) {
-        APInt Sentinel = IsSigned ? APInt::getSignedMinValue(NumBits)
-                                  : APInt::getMinValue(NumBits);
-        ValidRange = ConstantRange::getNonEmpty(Sentinel + 1, Sentinel);
-      } else {
-        if (IsSigned)
-          ValidRange =
-              ConstantRange::getNonEmpty(APInt::getSignedMinValue(NumBits),
-                                         APInt::getSignedMaxValue(NumBits) - 1);
-        else
-          ValidRange = ConstantRange::getNonEmpty(
-              APInt::getMinValue(NumBits), APInt::getMaxValue(NumBits) - 1);
-      }
-
-      LLVM_DEBUG(dbgs() << "LV: "
-                        << (isFindLastIVRecurrenceKind(Kind) ? "FindLastIV"
-                                                             : "FindFirstIV")
-                        << " valid range is " << ValidRange
-                        << ", and the range of " << *AR << " is " << IVRange
-                        << "\n");
-
-      // Ensure the induction variable does not wrap around by verifying that
-      // its range is fully contained within the valid range.
-      return ValidRange.contains(IVRange);
-    };
+    bool IsFindFirstIV = isFindFirstIVRecurrenceKind(Kind);
     if (isFindLastIVRecurrenceKind(Kind)) {
-      if (CheckRange(true))
+      if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+              cast<SCEVAddRecExpr>(AR), /*IsSigned=*/true, IsFindFirstIV, SE))
         return RecurKind::FindLastIVSMax;
-      if (CheckRange(false))
+      if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+              cast<SCEVAddRecExpr>(AR), /*IsSigned=*/false, IsFindFirstIV, SE))
         return RecurKind::FindLastIVUMax;
       return std::nullopt;
     }
     assert(isFindFirstIVRecurrenceKind(Kind) &&
            "Kind must either be a FindLastIV or FindFirstIV");
 
-    if (CheckRange(true))
+    if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+            cast<SCEVAddRecExpr>(AR), /*IsSigned=*/true, IsFindFirstIV, SE))
       return RecurKind::FindFirstIVSMin;
-    if (CheckRange(false))
+    if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+            cast<SCEVAddRecExpr>(AR), /*IsSigned=*/false, IsFindFirstIV, SE))
       return RecurKind::FindFirstIVUMin;
     return std::nullopt;
   };
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 9a94d29ba3307..2fa87b168f30b 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8587,8 +8587,7 @@ VPlanPtr LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(
 
   // Apply mandatory transformation to handle reductions with multiple in-loop
   // uses if possible, bail out otherwise.
-  if (!VPlanTransforms::runPass(VPlanTransforms::handleMultiUseReductions,
-                                *Plan))
+  if (!VPlanTransforms::handleMultiUseReductions(*Plan, *PSE.getSE(), OrigLoop))
     return nullptr;
   // Apply mandatory transformation to handle FP maxnum/minnum reduction with
   // NaNs if possible, bail out otherwise.
diff --git a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
index 329b62cee4fce..57f3e61fafdef 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanConstruction.cpp
@@ -13,13 +13,16 @@
 
 #include "LoopVectorizationPlanner.h"
 #include "VPlan.h"
+#include "VPlanAnalysis.h"
 #include "VPlanCFG.h"
 #include "VPlanDominatorTree.h"
 #include "VPlanPatternMatch.h"
 #include "VPlanTransforms.h"
+#include "VPlanUtils.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopIterator.h"
 #include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/ScalarEvolutionExpressions.h"
 #include "llvm/IR/InstrTypes.h"
 #include "llvm/IR/MDBuilder.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
@@ -997,7 +1000,48 @@ bool VPlanTransforms::handleMaxMinNumReductions(VPlan &Plan) {
   return true;
 }
 
-bool VPlanTransforms::handleMultiUseReductions(VPlan &Plan) {
+/// Try to convert FindLastIV to FindFirstIV reduction when using a strict
+/// predicate. Returns the new FindFirstIVPhiR on success, nullptr on failure.
+static VPReductionPHIRecipe *
+tryConvertToFindFirstIV(VPlan &Plan, VPReductionPHIRecipe *FindLastIVPhiR,
+                        VPValue *IVOp, ScalarEvolution &SE, const Loop *L) {
+  Type *Ty = VPTypeAnalysis(Plan).inferScalarType(FindLastIVPhiR);
+  unsigned NumBits = Ty->getIntegerBitWidth();
+
+  // Determine the reduction kind and sentinel based on the IV range.
+  RecurKind NewKind;
+  VPValue *NewSentinel;
+  auto *AR = cast<SCEVAddRecExpr>(vputils::getSCEVExprForVPValue(IVOp, SE, L));
+  if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+          AR, /*IsSigned=*/true, /*IsFindFirstIV=*/true, SE)) {
+    NewKind = RecurKind::FindFirstIVSMin;
+    NewSentinel = Plan.getConstantInt(APInt::getSignedMaxValue(NumBits));
+  } else if (RecurrenceDescriptor::isValidIVRangeForFindIV(
+                 AR, /*IsSigned=*/false, /*IsFindFirstIV=*/true, SE)) {
+    NewKind = RecurKind::FindFirstIVUMin;
+    NewSentinel = Plan.getConstantInt(APInt::getMaxValue(NumBits));
+  } else {
+    return nullptr;
+  }
+
+  // Create the new FindFirstIV reduction recipe.
+  assert(!FindLastIVPhiR->isInLoop() && !FindLastIVPhiR->isOrdered());
+  ReductionStyle Style = RdxUnordered{FindLastIVPhiR->getVFScaleFactor()};
+  auto *FindFirstIVPhiR =
+      new VPReductionPHIRecipe(nullptr, NewKind, *NewSentinel, Style,
+                               FindLastIVPhiR->hasUsesOutsideReductionChain());
+  FindFirstIVPhiR->addOperand(FindLastIVPhiR->getBackedgeValue());
+
+  FindFirstIVPhiR->insertBefore(FindLastIVPhiR);
+  VPInstruction *FindLastIVResult =
+      findUserOf<VPInstruction::ComputeFindIVResult>(FindLastIVPhiR);
+  FindLastIVPhiR->replaceAllUsesWith(FindFirstIVPhiR);
+  FindLastIVResult->setOperand(2, NewSentinel);
+  return FindFirstIVPhiR;
+}
+
+bool VPlanTransforms::handleMultiUseReductions(VPlan &Plan, ScalarEvolution &SE,
+                                               const Loop *L) {
   for (auto &PhiR : make_early_inc_range(
            Plan.getVectorLoopRegion()->getEntryBasicBlock()->phis())) {
     auto *MinMaxPhiR = dyn_cast<VPReductionPHIRecipe>(&PhiR);
@@ -1080,33 +1124,41 @@ bool VPlanTransforms::handleMultiUseReductions(VPlan &Plan) {
                            FindIVPhiR->getRecurrenceKind()))
       return false;
 
+    assert(!FindIVPhiR->isInLoop() && !FindIVPhiR->isOrdered() &&
+           "cannot handle inloop/ordered reductions yet");
+
     // TODO: Support cases where IVOp is the IV increment.
     if (!match(IVOp, m_TruncOrSelf(m_VPValue(IVOp))) ||
         !isa<VPWidenIntOrFpInductionRecipe>(IVOp))
       return false;
 
-    CmpInst::Predicate RdxPredicate = [RdxKind]() {
+    // Check if the predicate is compatible with the reduction kind.
+    bool IsValidPredicate = [RdxKind, Pred]() {
       switch (RdxKind) {
       case RecurKind::UMin:
-        return CmpInst::ICMP_UGE;
+        return Pred == CmpInst::ICMP_UGE || Pred == CmpInst::ICMP_UGT;
       case RecurKind::UMax:
-        return CmpInst::ICMP_ULE;
+        return Pred == CmpInst::ICMP_ULE || Pred == CmpInst::ICMP_ULT;
       case RecurKind::SMax:
-        return CmpInst::ICMP_SLE;
+        return Pred == CmpInst::ICMP_SLE || Pred == CmpInst::ICMP_SLT;
       case RecurKind::SMin:
-        return CmpInst::ICMP_SGE;
+        return Pred == CmpInst::ICMP_SGE || Pred == CmpInst::ICMP_SGT;
       default:
         llvm_unreachable("unhandled recurrence kind");
       }
     }();
 
-    // TODO: Strict predicates need to find the first IV value for which the
-    // predicate holds, not the last.
-    if (Pred != RdxPredicate)
+    if (!IsValidPredicate)
       return false;
 
-    assert(!FindIVPhiR->isInLoop() && !FindIVPhiR->isOrdered() &&
-           "cannot handle inloop/ordered reductions yet");
+    // For strict predicates, transform try to convert FindLastIV to
+    // FindFirstIV.
+    bool IsStrictPredicate = ICmpInst::isLT(Pred) || ICmpInst::isGT(Pred);
+    if (IsStrictPredicate) {
+      FindIVPhiR = tryConvertToFindFirstIV(Plan, FindIVPhiR, IVOp, SE, L);
+      if (!FindIVPhiR)
+        return false;
+    }
 
     // The reduction using MinMaxPhiR needs adjusting to compute the correct
     // result:
diff --git a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
index 4d46478aa7373..1f1552ad3fa68 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
@@ -163,6 +163,7 @@ bool VPRecipeBase::mayHaveSideEffects() const {
     return cast<VPExpressionRecipe>(this)->mayHaveSideEffects();
   case VPDerivedIVSC:
   case VPFirstOrderRecurrencePHISC:
+  case VPReductionPHISC:
   case VPPredInstPHISC:
   case VPVectorEndPointerSC:
     return false;
diff --git a/llvm/lib/Transforms/Vectorize/VPlanTransforms.h b/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
index afdf1655b4622..f9f918a7202e7 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
+++ b/llvm/lib/Transforms/Vectorize/VPlanTransforms.h
@@ -146,9 +146,10 @@ struct VPlanTransforms {
       const TargetLibraryInfo &TLI);
 
   /// Try to legalize reductions with multiple in-loop uses. Currently only
-  /// min/max reductions used by FindLastIV reductions are supported. Otherwise
-  /// return false.
-  static bool handleMultiUseReductions(VPlan &Plan);
+  /// min/max reductions used by FindLastIV and FindFirstIV reductions are
+  /// supported. Otherwise return false.
+  static bool handleMultiUseReductions(VPlan &Plan, ScalarEvolution &SE,
+                                       const Loop *L);
 
   /// Try to have all users of fixed-order recurrences appear after the recipe
   /// defining their previous value, by either sinking users or hoisting recipes
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
index 56d34a61be1db..7ef5d9e0e51a6 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/select-index.ll
@@ -5,11 +5,58 @@ define i64 @test_vectorize_select_umin_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_first_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 <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <2 x i64> [ splat (i64 100), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <2 x i64> [ splat (i64 100), %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ugt <2 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ugt <2 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[VEC_PHI4]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[VEC_PHI5]], <2 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <2 x i1> [[TMP2]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], 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> [[TMP4]], <2 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <2 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <2 x i1> [[TMP10]], <2 x i64> [[TMP6]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP12]], <2 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[MIDDLE_BLOCK]] ], [ 100, %[[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 [ 100, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; 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_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i64 [[MIN_VAL]], [[L]]
@@ -17,9 +64,9 @@ define i64 @test_vectorize_select_umin_first_idx(ptr %src, i64 %n) {
 ; 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:
@@ -74,7 +121,7 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-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.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]])
@@ -106,7 +153,7 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP3:![0-9]+]]
+; 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]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -136,11 +183,58 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_first_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 <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt <2 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sgt <2 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[VEC_PHI4]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[VEC_PHI5]], <2 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <2 x i1> [[TMP2]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.smin.v2i64(<2 x i64> [[TMP4]], <2 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smin.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <2 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <2 x i1> [[TMP10]], <2 x i64> [[TMP6]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP12]], <2 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i64 [[MIN_VAL]], [[L]]
@@ -148,9 +242,9 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; 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:
@@ -205,7 +299,7 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-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.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]])
@@ -237,7 +331,7 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP5:![0-9]+]]
+; 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]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -267,11 +361,58 @@ define i64 @test_vectorize_select_umax_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_first_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 <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ult <2 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ult <2 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[VEC_PHI4]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[VEC_PHI5]], <2 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <2 x i1> [[TMP2]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP10:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.umax.v2i64(<2 x i64> [[TMP4]], <2 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.umax.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <2 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <2 x i1> [[TMP10]], <2 x i64> [[TMP6]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP12]], <2 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[MIN_VAL]], [[L]]
@@ -279,9 +420,9 @@ define i64 @test_vectorize_select_umax_first_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP11:![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:
@@ -336,7 +477,7 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP12:![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]])
@@ -368,7 +509,7 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; 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-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP13:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -398,11 +539,58 @@ define i64 @test_vectorize_select_smax_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_first_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 <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <2 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <2 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <2 x i64> [[VEC_IND]], splat (i64 2)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 2
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <2 x i64>, ptr [[GEP1]], align 8
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <2 x i64>, ptr [[TMP1]], align 8
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp slt <2 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp slt <2 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[VEC_PHI4]], <2 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[VEC_PHI5]], <2 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <2 x i1> [[TMP2]], <2 x i64> [[VEC_IND]], <2 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <2 x i1> [[TMP3]], <2 x i64> [[STEP_ADD]], <2 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <2 x i64> [[STEP_ADD]], splat (i64 2)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP14:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <2 x i64> @llvm.smax.v2i64(<2 x i64> [[TMP4]], <2 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v2i64(<2 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <2 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <2 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <2 x i1> [[TMP10]], <2 x i64> [[TMP6]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <2 x i1> [[TMP11]], <2 x i64> [[TMP7]], <2 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <2 x i64> @llvm.umin.v2i64(<2 x i64> [[TMP12]], <2 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v2i64(<2 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[SCALAR_PH]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
 ; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 8
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i64 [[MIN_VAL]], [[L]]
@@ -410,9 +598,9 @@ define i64 @test_vectorize_select_smax_first_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP15:![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:
@@ -467,7 +655,7 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP16:![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]])
@@ -499,7 +687,7 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP9:![0-9]+]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP17:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -586,10 +774,10 @@ define i32 @test_multi_use_reduction_with_trunc_iv(ptr %src, i32 %n) {
 ; CHECK-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i32> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ <i32 1, i32 2, i32 3, i32 4>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i32> [[VEC_IND]], splat (i32 4)
-; CHECK-NEXT:    [[IV:%.*]] = add i64 1, [[INDEX]]
-; CHECK-NEXT:    [[GEP_SRC:%.*]] = getelementptr i32, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i32, ptr [[GEP_SRC]], i64 4
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[GEP_SRC]], align 4
+; CHECK-NEXT:    [[IV1:%.*]] = add i64 1, [[INDEX]]
+; CHECK-NEXT:    [[GEP_SRC1:%.*]] = getelementptr i32, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i32, ptr [[GEP_SRC1]], i64 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[GEP_SRC1]], align 4
 ; CHECK-NEXT:    [[WIDE_LOAD4:%.*]] = load <4 x i32>, ptr [[TMP2]], align 4
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp ugt <4 x i32> [[WIDE_LOAD]], [[VEC_PHI2]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp ugt <4 x i32> [[WIDE_LOAD4]], [[VEC_PHI3]]
@@ -600,7 +788,7 @@ define i32 @test_multi_use_reduction_with_trunc_iv(ptr %src, i32 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 8
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i32> [[STEP_ADD]], splat (i32 4)
 ; CHECK-NEXT:    [[TMP9:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
-; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP10:![0-9]+]]
+; CHECK-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP18:![0-9]+]]
 ; CHECK:       [[MIDDLE_BLOCK]]:
 ; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i32> @llvm.umin.v4i32(<4 x i32> [[TMP5]], <4 x i32> [[TMP6]])
 ; CHECK-NEXT:    [[TMP10:%.*]] = call i32 @llvm.vector.reduce.umin.v4i32(<4 x i32> [[RDX_MINMAX]])
@@ -622,18 +810,18 @@ define i32 @test_multi_use_reduction_with_trunc_iv(ptr %src, i32 %n) {
 ; CHECK-NEXT:    [[BC_MERGE_RDX6:%.*]] = phi i32 [ [[TMP10]], %[[MIDDLE_BLOCK]] ], [ 0, %[[LOOP_PREHEADER]] ]
 ; CHECK-NEXT:    br label %[[LOOP:.*]]
 ; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[IV1:%.*]] = phi i64 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ]
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i32 [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ], [ [[BC_MERGE_RDX]], %[[SCALAR_PH]] ]
 ; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i32 [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ], [ [[BC_MERGE_RDX6]], %[[SCALAR_PH]] ]
-; CHECK-NEXT:    [[GEP_SRC1:%.*]] = getelementptr i32, ptr [[SRC]], i64 [[IV1]]
-; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[GEP_SRC1]], align 4
+; CHECK-NEXT:    [[GEP_SRC:%.*]] = getelementptr i32, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[GEP_SRC]], align 4
 ; CHECK-NEXT:    [[C_0:%.*]] = icmp ugt i32 [[L]], [[MIN_VAL]]
 ; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i32 @llvm.umin.i32(i32 [[L]], i32 [[MIN_VAL]])
-; CHECK-NEXT:    [[IV_TRUNC:%.*]] = trunc i64 [[IV1]] to i32
+; CHECK-NEXT:    [[IV_TRUNC:%.*]] = trunc i64 [[IV]] to i32
 ; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[C_0]], i32 [[MIN_IDX]], i32 [[IV_TRUNC]]
-; CHECK-NEXT:    [[IV_NEXT]] = add i64 [[IV1]], 1
-; CHECK-NEXT:    [[EC:%.*]] = icmp eq i64 [[IV1]], [[N_EXT]]
-; CHECK-NEXT:    br i1 [[EC]], label %[[EXIT_LOOPEXIT]], label %[[LOOP]], !llvm.loop [[LOOP11:![0-9]+]]
+; CHECK-NEXT:    [[IV_NEXT]] = add i64 [[IV]], 1
+; CHECK-NEXT:    [[EC:%.*]] = icmp eq i64 [[IV]], [[N_EXT]]
+; CHECK-NEXT:    br i1 [[EC]], label %[[EXIT_LOOPEXIT]], label %[[LOOP]], !llvm.loop [[LOOP19:![0-9]+]]
 ; CHECK:       [[EXIT_LOOPEXIT]]:
 ; CHECK-NEXT:    [[MIN_IDX_NEXT_LCSSA:%.*]] = phi i32 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    br label %[[EXIT]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
index 1638360d08e99..43e94690faf93 100644
--- a/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-index-interleaving.ll
@@ -5,11 +5,58 @@ define i64 @test_vectorize_select_umin_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_first_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i64> [ splat (i64 50), %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <4 x i64> [ splat (i64 50), %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ugt <4 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ugt <4 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI4]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI5]], <4 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], 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> [[TMP4]], <4 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <4 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <4 x i1> [[TMP10]], <4 x i64> [[TMP6]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP12]], <4 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[MIDDLE_BLOCK]] ], [ 50, %[[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 [ 50, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; 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_RDX6]], %[[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 ugt i64 [[MIN_VAL]], [[L]]
@@ -17,9 +64,9 @@ define i64 @test_vectorize_select_umin_first_idx(ptr %src, i64 %n) {
 ; 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:
@@ -74,7 +121,7 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-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.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]])
@@ -106,7 +153,7 @@ define i64 @test_vectorize_select_umin_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP3:![0-9]+]]
+; 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]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -136,11 +183,58 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_first_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt <4 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp sgt <4 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI4]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI5]], <4 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[TMP4]], <4 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <4 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <4 x i1> [[TMP10]], <4 x i64> [[TMP6]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP12]], <4 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[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 sgt i64 [[MIN_VAL]], [[L]]
@@ -148,9 +242,9 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; 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:
@@ -205,7 +299,7 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-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.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]])
@@ -237,7 +331,7 @@ define i64 @test_vectorize_select_smin_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP5:![0-9]+]]
+; 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]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -267,11 +361,58 @@ define i64 @test_vectorize_select_umax_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_first_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ult <4 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ult <4 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI4]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI5]], <4 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP10:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[TMP4]], <4 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.umax.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <4 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <4 x i1> [[TMP10]], <4 x i64> [[TMP6]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP12]], <4 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[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 ult i64 [[MIN_VAL]], [[L]]
@@ -279,9 +420,9 @@ define i64 @test_vectorize_select_umax_first_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP11:![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:
@@ -336,7 +477,7 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP12:![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]])
@@ -368,7 +509,7 @@ define i64 @test_vectorize_select_umax_last_idx(ptr %src, i64 %n) {
 ; 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-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP13:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
@@ -398,11 +539,58 @@ define i64 @test_vectorize_select_smax_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_first_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 -1), %[[VECTOR_PH]] ], [ [[TMP7:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP5:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i64, ptr [[GEP1]], i64 4
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP1]], align 4
+; CHECK-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i64>, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp slt <4 x i64> [[VEC_PHI4]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp slt <4 x i64> [[VEC_PHI5]], [[WIDE_LOAD6]]
+; CHECK-NEXT:    [[TMP4]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI4]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP5]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI5]], <4 x i64> [[WIDE_LOAD6]])
+; CHECK-NEXT:    [[TMP6]] = select <4 x i1> [[TMP2]], <4 x i64> [[VEC_IND]], <4 x i64> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP7]] = select <4 x i1> [[TMP3]], <4 x i64> [[STEP_ADD]], <4 x i64> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 8
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[STEP_ADD]], splat (i64 4)
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP14:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[RDX_MINMAX:%.*]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[TMP4]], <4 x i64> [[TMP5]])
+; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.smax.v4i64(<4 x i64> [[RDX_MINMAX]])
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP9]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq <4 x i64> [[TMP4]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp eq <4 x i64> [[TMP5]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP12:%.*]] = select <4 x i1> [[TMP10]], <4 x i64> [[TMP6]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[TMP13:%.*]] = select <4 x i1> [[TMP11]], <4 x i64> [[TMP7]], <4 x i64> splat (i64 -1)
+; CHECK-NEXT:    [[RDX_MINMAX7:%.*]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[TMP12]], <4 x i64> [[TMP13]])
+; CHECK-NEXT:    [[TMP14:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[RDX_MINMAX7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP14]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP14]], 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 [ [[TMP9]], %[[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:    [[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_RDX6]], %[[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 slt i64 [[MIN_VAL]], [[L]]
@@ -410,9 +598,9 @@ define i64 @test_vectorize_select_smax_first_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP15:![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:
@@ -467,7 +655,7 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 8
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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-NEXT:    br i1 [[TMP9]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP16:![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]])
@@ -499,7 +687,7 @@ define i64 @test_vectorize_select_smax_last_idx(ptr %src, i64 %n) {
 ; 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 [[LOOP9:![0-9]+]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP17:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
index 2117704950b84..61ad461896ed4 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smax-last-index.ll
@@ -159,21 +159,56 @@ define i64 @test_vectorize_select_smax_idx_select_ops_flipped(ptr %src, i64 %n)
 ; CHECK-LABEL: define i64 @test_vectorize_select_smax_idx_select_ops_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[TMP1:%.*]] = icmp sle <4 x i64> [[WIDE_LOAD]], [[VEC_PHI2]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.smax.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i64> [[VEC_PHI]], <4 x i64> [[VEC_IND]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; 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:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.smax.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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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:    [[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 [[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 [[MIN_IDX]], i64 [[IV]]
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[MAX_IDX]], i64 [[IV]]
 ; 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:
@@ -308,7 +343,7 @@ define i64 @test_vectorize_select_smax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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:    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_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
@@ -336,7 +371,7 @@ define i64 @test_vectorize_select_smax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; 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]], !llvm.loop [[LOOP7:![0-9]+]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-smin-first-index.ll b/llvm/test/Transforms/LoopVectorize/select-smin-first-index.ll
index bf5362f2e740f..e051e62d34882 100644
--- a/llvm/test/Transforms/LoopVectorize/select-smin-first-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-smin-first-index.ll
@@ -7,21 +7,56 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_first_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 <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 -1), %[[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 sgt <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; 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 nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.smin.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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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 sgt 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 [[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:
@@ -48,22 +83,35 @@ exit:
 define i64 @test_vectorize_select_smin_first_idx_signed_sentinel_possible(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_first_idx_signed_sentinel_possible(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
-; CHECK-NEXT:  [[ENTRY:.*]]:
-; CHECK-NEXT:    br label %[[LOOP:.*]]
-; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDEX_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:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[INDEX:%.*]] = 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 9223372036854775807), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[INDEX]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[TMP0]], align 4
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt 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 [[INDEX]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw nsw i64 [[INDEX]], 1
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP0]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; 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 [[INDEX]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], 100
-; CHECK-NEXT:    br i1 [[TMP4]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.smin.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:    [[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 9223372036854775807)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], 9223372036854775807
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], i64 0
+; CHECK-NEXT:    br label %[[EXIT:.*]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RDX_SELECT:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
 ; CHECK-NEXT:    ret i64 [[RDX_SELECT]]
 ;
 entry:
@@ -91,21 +139,56 @@ define i64 @test_vectorize_select_smin_first_idx_cond_flipped(ptr %src, i64 %n)
 ; CHECK-LABEL: define i64 @test_vectorize_select_smin_first_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 -1), %[[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 slt <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; 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 nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP5:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.smin.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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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 slt 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 [[LOOP6:![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:
@@ -176,23 +259,35 @@ exit:
 define i32 @test_vectorize_select_smin_first_idx_trunc_valid(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i32 @test_vectorize_select_smin_first_idx_trunc_valid(
 ; 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 i32 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[IV_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i32> [ splat (i32 2147483647), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ <i32 0, i32 1, i32 2, i32 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i64 [[MIN_VAL]], [[L]]
-; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.smin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[T:%.*]] = trunc i64 [[IV]] to i32
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i32 [[T]], i32 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.smin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i32> [[VEC_IND]], <4 x i32> [[VEC_PHI]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i32> [[VEC_IND]], splat (i32 4)
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], 100
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP7:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.smin.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:    [[TMP6:%.*]] = icmp eq <4 x i64> [[TMP2]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP7:%.*]] = select <4 x i1> [[TMP6]], <4 x i32> [[TMP3]], <4 x i32> splat (i32 2147483647)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i32 @llvm.vector.reduce.smin.v4i32(<4 x i32> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i32 [[TMP8]], 2147483647
+; CHECK-NEXT:    [[RES:%.*]] = select i1 [[RDX_SELECT_CMP]], i32 [[TMP8]], i32 0
+; CHECK-NEXT:    br label %[[EXIT:.*]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i32 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
 ; CHECK-NEXT:    ret i32 [[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 1bb3d017a67cd..3f9d73a5a496b 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umax-last-index.ll
@@ -159,21 +159,56 @@ define i64 @test_vectorize_select_umax_idx_select_ops_flipped(ptr %src, i64 %n)
 ; CHECK-LABEL: define i64 @test_vectorize_select_umax_idx_select_ops_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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[TMP1:%.*]] = icmp ule <4 x i64> [[WIDE_LOAD]], [[VEC_PHI2]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umax.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i64> [[VEC_PHI]], <4 x i64> [[VEC_IND]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; 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:    [[TMP5:%.*]] = call i64 @llvm.vector.reduce.umax.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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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:    [[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 [[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 [[MIN_IDX]], i64 [[IV]]
+; CHECK-NEXT:    [[MAX_IDX_NEXT]] = select i1 [[CMP]], i64 [[MAX_IDX]], i64 [[IV]]
 ; 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:
@@ -308,7 +343,7 @@ define i64 @test_vectorize_select_umax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <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:    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_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP6]], i64 0
@@ -336,7 +371,7 @@ define i64 @test_vectorize_select_umax_idx_min_ops_switched(ptr %src, i64 %n) {
 ; 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]], !llvm.loop [[LOOP7:![0-9]+]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP9:![0-9]+]]
 ; CHECK:       [[EXIT]]:
 ; CHECK-NEXT:    [[RES:%.*]] = phi i64 [ [[MAX_IDX_NEXT]], %[[LOOP]] ], [ [[RDX_SELECT]], %[[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i64 [[RES]]
diff --git a/llvm/test/Transforms/LoopVectorize/select-umin-first-index.ll b/llvm/test/Transforms/LoopVectorize/select-umin-first-index.ll
index 192740fcf6dec..47c0ad939024d 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umin-first-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umin-first-index.ll
@@ -7,11 +7,46 @@ 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 -1), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[TMP1:%.*]] = icmp ugt <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; 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 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; 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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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:    [[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 ugt i64 [[MIN_VAL]], [[L]]
@@ -19,9 +54,9 @@ define i64 @test_vectorize_select_umin_idx(ptr %src, i64 %n) {
 ; 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:
@@ -48,22 +83,35 @@ exit:
 define i64 @test_vectorize_select_umin_idx_signed_sentinel_possible(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i64 @test_vectorize_select_umin_idx_signed_sentinel_possible(
 ; CHECK-SAME: ptr [[SRC:%.*]], i64 [[N:%.*]]) {
-; CHECK-NEXT:  [[ENTRY:.*]]:
-; CHECK-NEXT:    br label %[[LOOP:.*]]
-; CHECK:       [[LOOP]]:
-; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDEX_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:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[INDEX:%.*]] = 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 9223372036854775807), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[INDEX]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[TMP0]], align 4
-; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt 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 [[INDEX]], i64 [[MIN_IDX]]
-; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw nsw i64 [[INDEX]], 1
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[TMP0]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp ugt <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; 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 [[INDEX]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], 100
-; CHECK-NEXT:    br i1 [[TMP4]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; 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:    [[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 9223372036854775807)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.smin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], 9223372036854775807
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], i64 0
+; CHECK-NEXT:    br label %[[EXIT:.*]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RDX_SELECT:%.*]] = phi i64 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
 ; CHECK-NEXT:    ret i64 [[RDX_SELECT]]
 ;
 entry:
@@ -91,11 +139,46 @@ 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:    [[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 -1), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[TMP1:%.*]] = icmp ult <4 x i64> [[WIDE_LOAD]], [[VEC_PHI2]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI2]], <4 x i64> [[WIDE_LOAD]])
+; 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 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP5:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; 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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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:    [[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 ult i64 [[L]], [[MIN_VAL]]
@@ -103,9 +186,9 @@ define i64 @test_vectorize_select_umin_idx_cond_flipped(ptr %src, i64 %n) {
 ; 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 [[LOOP6:![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:
@@ -263,11 +346,46 @@ 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 -1), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[TMP1:%.*]] = icmp ugt <4 x i64> [[VEC_PHI2]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[WIDE_LOAD]], <4 x i64> [[VEC_PHI2]])
+; 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 [[IV1]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP7:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; 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:    [[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 -1)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.umin.v4i64(<4 x i64> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i64 [[TMP8]], -1
+; CHECK-NEXT:    [[RDX_SELECT:%.*]] = select i1 [[RDX_SELECT_CMP]], i64 [[TMP8]], 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 [ [[TMP5]], %[[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:    [[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 ugt i64 [[MIN_VAL]], [[L]]
@@ -275,9 +393,9 @@ define i64 @test_vectorize_select_umin_idx_min_ops_switched(ptr %src, i64 %n) {
 ; 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 [[LOOP8:![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:
@@ -432,23 +550,35 @@ exit:
 define i32 @test_vectorize_select_umin_idx_with_trunc_valid(ptr %src, i64 %n) {
 ; CHECK-LABEL: define i32 @test_vectorize_select_umin_idx_with_trunc_valid(
 ; 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 i32 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[IV_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i32> [ splat (i32 2147483647), %[[VECTOR_PH]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ <i32 0, i32 1, i32 2, i32 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
-; CHECK-NEXT:    [[L:%.*]] = load i64, ptr [[GEP]], align 4
-; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i64 [[MIN_VAL]], [[L]]
-; CHECK-NEXT:    [[MIN_VAL_NEXT]] = tail call i64 @llvm.umin.i64(i64 [[MIN_VAL]], i64 [[L]])
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc i64 [[IV]] to i32
-; CHECK-NEXT:    [[MIN_IDX_NEXT]] = select i1 [[CMP]], i32 [[TRUNC]], i32 [[MIN_IDX]]
-; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp ugt <4 x i64> [[VEC_PHI1]], [[WIDE_LOAD]]
+; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
+; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i32> [[VEC_IND]], <4 x i32> [[VEC_PHI]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 4
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i32> [[VEC_IND]], splat (i32 4)
 ; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[IV_NEXT]], 100
-; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[LOOP]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP9:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; 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:    [[TMP6:%.*]] = icmp eq <4 x i64> [[TMP2]], [[BROADCAST_SPLAT]]
+; CHECK-NEXT:    [[TMP7:%.*]] = select <4 x i1> [[TMP6]], <4 x i32> [[TMP3]], <4 x i32> splat (i32 2147483647)
+; CHECK-NEXT:    [[TMP8:%.*]] = call i32 @llvm.vector.reduce.smin.v4i32(<4 x i32> [[TMP7]])
+; CHECK-NEXT:    [[RDX_SELECT_CMP:%.*]] = icmp ne i32 [[TMP8]], 2147483647
+; CHECK-NEXT:    [[RES:%.*]] = select i1 [[RDX_SELECT_CMP]], i32 [[TMP8]], i32 0
+; CHECK-NEXT:    br label %[[EXIT:.*]]
 ; CHECK:       [[EXIT]]:
-; CHECK-NEXT:    [[RES:%.*]] = phi i32 [ [[MIN_IDX_NEXT]], %[[LOOP]] ]
 ; CHECK-NEXT:    ret i32 [[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 3e69c1907269b..6a13f10507cf4 100644
--- a/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
+++ b/llvm/test/Transforms/LoopVectorize/select-umin-last-index.ll
@@ -168,16 +168,16 @@ define i64 @test_vectorize_select_umin_idx_select_ops_flipped(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]] ], [ [[TMP3:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x i64> [ splat (i64 120), %[[VECTOR_PH]] ], [ [[TMP2:%.*]], %[[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:    [[GEP:%.*]] = getelementptr i64, ptr [[SRC]], i64 [[IV]]
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i64>, ptr [[GEP]], align 4
 ; CHECK-NEXT:    [[TMP1:%.*]] = icmp ugt <4 x i64> [[WIDE_LOAD]], [[VEC_PHI1]]
 ; CHECK-NEXT:    [[TMP2]] = call <4 x i64> @llvm.umin.v4i64(<4 x i64> [[VEC_PHI1]], <4 x i64> [[WIDE_LOAD]])
 ; CHECK-NEXT:    [[TMP3]] = select <4 x i1> [[TMP1]], <4 x i64> [[VEC_PHI]], <4 x i64> [[VEC_IND]]
-; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV1]], 4
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[IV]], 4
 ; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
 ; 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]+]]
@@ -198,15 +198,15 @@ define i64 @test_vectorize_select_umin_idx_select_ops_flipped(ptr %src, i64 %n)
 ; CHECK-NEXT:    [[BC_MERGE_RDX2:%.*]] = phi i64 [ [[TMP5]], %[[MIDDLE_BLOCK]] ], [ 120, %[[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 ugt 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]], !llvm.loop [[LOOP7:![0-9]+]]
 ; CHECK:       [[EXIT]]:
diff --git a/llvm/test/Transforms/LoopVectorize/smax-idx.ll b/llvm/test/Transforms/LoopVectorize/smax-idx.ll
index 37dcd7fc7e39f..6c613e0a9f602 100644
--- a/llvm/test/Transforms/LoopVectorize/smax-idx.ll
+++ b/llvm/test/Transforms/LoopVectorize/smax-idx.ll
@@ -1,10 +1,30 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
 ; RUN: opt -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=1 -S < %s | FileCheck %s --check-prefix=CHECK
 ; RUN: opt -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=4 -S < %s | FileCheck %s --check-prefix=CHECK
 ; RUN: opt -passes=loop-vectorize -force-vector-width=1 -force-vector-interleave=4 -S < %s | FileCheck %s --check-prefix=CHECK
 
 define i64 @smax_idx(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP1]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i64 [[MAX_09]], [[TMP0]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 [[INDVARS_IV]], i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP1]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body
@@ -31,8 +51,27 @@ exit:
 ; Check the different order of reduction phis.
 ;
 define i64 @smax_idx_inverted_phi(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_inverted_phi(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_inverted_phi(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP1]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i64 [[MAX_09]], [[TMP0]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 [[INDVARS_IV]], i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP1]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body
@@ -64,9 +103,6 @@ exit:
 ; MMI pattern.
 ;
 define i64 @smax_idx_max_no_exit_user(ptr nocapture readonly %a, i64 %mm, i64 %ii, i64 %n) {
-; CHECK-LABEL: @smax_idx_max_no_exit_user(
-; CHECK-NOT:   vector.body:
-;
 entry:
   br label %for.body
 
@@ -95,8 +131,27 @@ exit:
 ; check whether icmp can be duplicated.
 ;
 define i64 @smax_idx_select_cmp(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_select_cmp(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_select_cmp(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[SPEC_SELECT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i64 [[MAX_09]], [[TMP0]]
+; CHECK-NEXT:    [[SPEC_SELECT]] = select i1 [[CMP1]], i64 [[TMP0]], i64 [[MAX_09]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 [[INDVARS_IV]], i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[SPEC_SELECT_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[SPEC_SELECT_LCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body
@@ -123,8 +178,27 @@ exit:
 ; Check sge case.
 ;
 define i64 @smax_idx_inverted_pred(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_inverted_pred(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_inverted_pred(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP1]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp sge i64 [[TMP0]], [[MAX_09]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 [[INDVARS_IV]], i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP1]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body
@@ -151,8 +225,27 @@ exit:
 ; In such cases, the last index should be extracted.
 ;
 define i64 @smax_idx_extract_last(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_extract_last(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_extract_last(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP1]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1_NOT:%.*]] = icmp sgt i64 [[MAX_09]], [[TMP0]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1_NOT]], i64 [[IDX_011]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP1]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body
@@ -179,8 +272,29 @@ exit:
 ; The operands of smax intrinsic and icmp are not the same to be recognized as MMI.
 ;
 define i64 @smax_idx_not_vec_1(ptr nocapture readonly %a, ptr nocapture readonly %b, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_not_vec_1(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_not_vec_1(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], ptr readonly captures(none) [[B:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP2:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[ARRAYIDX_01:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP2]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i64 [[MAX_09]], [[TMP1]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 [[INDVARS_IV]], i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP2]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
   entry:
   br label %for.body
@@ -209,8 +323,27 @@ exit:
 ; It cannot be recognized as MMI when the operand of index select is not an induction variable.
 ;
 define i64 @smax_idx_not_vec_2(ptr nocapture readonly %a, i64 %mm, i64 %ii, ptr nocapture writeonly %res_max, i64 %n) {
-; CHECK-LABEL: @smax_idx_not_vec_2(
-; CHECK-NOT:   vector.body:
+; CHECK-LABEL: define i64 @smax_idx_not_vec_2(
+; CHECK-SAME: ptr readonly captures(none) [[A:%.*]], i64 [[MM:%.*]], i64 [[II:%.*]], ptr writeonly captures(none) [[RES_MAX:%.*]], i64 [[N:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_09:%.*]] = phi i64 [ [[MM]], %[[ENTRY]] ], [ [[TMP1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IDX_011:%.*]] = phi i64 [ [[II]], %[[ENTRY]] ], [ [[SPEC_SELECT7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[TMP1]] = tail call i64 @llvm.smax.i64(i64 [[MAX_09]], i64 [[TMP0]])
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i64 [[MAX_09]], [[TMP0]]
+; CHECK-NEXT:    [[SPEC_SELECT7]] = select i1 [[CMP1]], i64 123, i64 [[IDX_011]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label %[[EXIT:.*]], label %[[FOR_BODY]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    [[DOTLCSSA:%.*]] = phi i64 [ [[TMP1]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[SPEC_SELECT7_LCSSA:%.*]] = phi i64 [ [[SPEC_SELECT7]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    store i64 [[DOTLCSSA]], ptr [[RES_MAX]], align 4
+; CHECK-NEXT:    ret i64 [[SPEC_SELECT7_LCSSA]]
 ;
 entry:
   br label %for.body



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