[llvm] 572cfa3 - [LV] Use SCEV for uniformity analysis across VF

Florian Hahn via llvm-commits llvm-commits at lists.llvm.org
Wed May 31 08:01:16 PDT 2023


Author: Florian Hahn
Date: 2023-05-31T16:01:00+01:00
New Revision: 572cfa3fde5433c889b339e9cfa6dfaa23e5f2ee

URL: https://github.com/llvm/llvm-project/commit/572cfa3fde5433c889b339e9cfa6dfaa23e5f2ee
DIFF: https://github.com/llvm/llvm-project/commit/572cfa3fde5433c889b339e9cfa6dfaa23e5f2ee.diff

LOG: [LV] Use SCEV for uniformity analysis across VF

This patch uses SCEV to check if a value is uniform across a given VF.

The basic idea is to construct SCEVs where the AddRecs of the loop are
adjusted to reflect the version in the vectorized loop (Step multiplied
by VF). We construct a SCEV for the value of the vector lane 0
(offset 0) compare it to the expressions for lanes 1 to the last vector
lane (VF - 1). If they are equal, consider the expression uniform.

While re-writing expressions, we also need to catch expressions we
cannot determine uniformity (e.g. SCEVUnknown).

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D148841

Added: 
    

Modified: 
    llvm/include/llvm/Analysis/LoopAccessAnalysis.h
    llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
    llvm/lib/Analysis/LoopAccessAnalysis.cpp
    llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
    llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    llvm/test/Transforms/LoopVectorize/X86/uniform_mem_op.ll
    llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll
    llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1.ll
    llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_and.ll
    llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_div_urem.ll
    llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_lshr.ll
    llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction2.ll

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Analysis/LoopAccessAnalysis.h b/llvm/include/llvm/Analysis/LoopAccessAnalysis.h
index a45f117249e69..9fe4a35284866 100644
--- a/llvm/include/llvm/Analysis/LoopAccessAnalysis.h
+++ b/llvm/include/llvm/Analysis/LoopAccessAnalysis.h
@@ -588,8 +588,9 @@ class LoopAccessInfo {
   static bool blockNeedsPredication(BasicBlock *BB, Loop *TheLoop,
                                     DominatorTree *DT);
 
-  /// Returns true if the value V is uniform within the loop.
-  bool isUniform(Value *V) const;
+  /// Returns true if value \p V is uniform across \p VF lanes, when \p VF is
+  /// provided, and otherwise if \p V is invariant across all loop iterations.
+  bool isUniform(Value *V, std::optional<ElementCount> VF = std::nullopt) const;
 
   uint64_t getMaxSafeDepDistBytes() const { return MaxSafeDepDistBytes; }
   unsigned getNumStores() const { return NumStores; }

diff  --git a/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h b/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
index ec71eb178af17..c666267456213 100644
--- a/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
+++ b/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
@@ -347,12 +347,15 @@ class LoopVectorizationLegality {
   /// loop. Do not use after invoking 'createVectorizedLoopSkeleton' (PR34965).
   int isConsecutivePtr(Type *AccessTy, Value *Ptr) const;
 
-  /// Returns true if the value V is uniform within the loop.
-  bool isUniform(Value *V) const;
+  /// Returns true if value V is uniform across \p VF lanes, when \p VF is
+  /// provided, and otherwise if \p V is invariant across all loop iterations.
+  bool isUniform(Value *V, std::optional<ElementCount> VF = std::nullopt) const;
 
   /// A uniform memory op is a load or store which accesses the same memory
-  /// location on all lanes.
-  bool isUniformMemOp(Instruction &I) const;
+  /// location on all \p VF lanes, if \p VF is provided and otherwise if the
+  /// memory location is invariant.
+  bool isUniformMemOp(Instruction &I,
+                      std::optional<ElementCount> VF = std::nullopt) const;
 
   /// Returns the information that we collected about runtime memory check.
   const RuntimePointerChecking *getRuntimePointerChecking() const {

diff  --git a/llvm/lib/Analysis/LoopAccessAnalysis.cpp b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
index 6c271a8b2f7c5..6934c48c75968 100644
--- a/llvm/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
@@ -2532,7 +2532,93 @@ OptimizationRemarkAnalysis &LoopAccessInfo::recordAnalysis(StringRef RemarkName,
   return *Report;
 }
 
-bool LoopAccessInfo::isUniform(Value *V) const {
+namespace {
+/// A rewriter to build the SCEVs for each of the VF lanes in the expected
+/// vectorized loop, which can then be compared to detect their uniformity. This
+/// is done by replacing the AddRec SCEVs of the original scalar loop (TheLoop)
+/// with new AddRecs where the step is multiplied by StepMultiplier and Offset *
+/// Step is added. Also checks if all sub-expressions are analyzable w.r.t.
+/// uniformity.
+class SCEVAddRecForUniformityRewriter
+    : public SCEVRewriteVisitor<SCEVAddRecForUniformityRewriter> {
+  /// Multiplier to be applied to the step of AddRecs in TheLoop.
+  unsigned StepMultiplier;
+
+  /// Offset to be added to the AddRecs in TheLoop.
+  unsigned Offset;
+
+  /// Loop for which to rewrite AddRecsFor.
+  Loop *TheLoop;
+
+  /// Is any sub-expressions not analyzable w.r.t. uniformity?
+  bool CannotAnalyze = false;
+
+  bool canAnalyze() const { return !CannotAnalyze; }
+
+public:
+  SCEVAddRecForUniformityRewriter(ScalarEvolution &SE, unsigned StepMultiplier,
+                                  unsigned Offset, Loop *TheLoop)
+      : SCEVRewriteVisitor(SE), StepMultiplier(StepMultiplier), Offset(Offset),
+        TheLoop(TheLoop) {}
+
+  const SCEV *visitAddRecExpr(const SCEVAddRecExpr *Expr) {
+    assert(Expr->getLoop() == TheLoop &&
+           "addrec outside of TheLoop must be invariant and should have been "
+           "handled earlier");
+    // Build a new AddRec by multiplying the step by StepMultiplier and
+    // incrementing the start by Offset * step.
+    Type *Ty = Expr->getType();
+    auto *Step = Expr->getStepRecurrence(SE);
+    auto *NewStep = SE.getMulExpr(Step, SE.getConstant(Ty, StepMultiplier));
+    auto *ScaledOffset = SE.getMulExpr(Step, SE.getConstant(Ty, Offset));
+    auto *NewStart = SE.getAddExpr(Expr->getStart(), ScaledOffset);
+    return SE.getAddRecExpr(NewStart, NewStep, TheLoop, SCEV::FlagAnyWrap);
+  }
+
+  const SCEV *visit(const SCEV *S) {
+    if (CannotAnalyze || SE.isLoopInvariant(S, TheLoop))
+      return S;
+    return SCEVRewriteVisitor<SCEVAddRecForUniformityRewriter>::visit(S);
+  }
+
+  const SCEV *visitUnknown(const SCEVUnknown *S) {
+    if (SE.isLoopInvariant(S, TheLoop))
+      return S;
+    // The value could vary across iterations.
+    CannotAnalyze = true;
+    return S;
+  }
+
+  const SCEV *visitCouldNotCompute(const SCEVCouldNotCompute *S) {
+    // Could not analyze the expression.
+    CannotAnalyze = true;
+    return S;
+  }
+
+  static const SCEV *rewrite(const SCEV *S, ScalarEvolution &SE,
+                             unsigned StepMultiplier, unsigned Offset,
+                             Loop *TheLoop) {
+    /// Bail out if the expression does not contain an UDiv expression.
+    /// Uniform values which are not loop invariant require operations to strip
+    /// out the lowest bits. For now just look for UDivs and use it to avoid
+    /// re-writing UDIV-free expressions for other lanes to limit compile time.
+    if (!SCEVExprContains(S,
+                          [](const SCEV *S) { return isa<SCEVUDivExpr>(S); }))
+      return SE.getCouldNotCompute();
+
+    SCEVAddRecForUniformityRewriter Rewriter(SE, StepMultiplier, Offset,
+                                             TheLoop);
+    const SCEV *Result = Rewriter.visit(S);
+
+    if (Rewriter.canAnalyze())
+      return Result;
+    return SE.getCouldNotCompute();
+  }
+};
+
+} // namespace
+
+bool LoopAccessInfo::isUniform(Value *V, std::optional<ElementCount> VF) const {
   auto *SE = PSE->getSE();
   // Since we rely on SCEV for uniformity, if the type is not SCEVable, it is
   // never considered uniform.
@@ -2540,7 +2626,30 @@ bool LoopAccessInfo::isUniform(Value *V) const {
   // trivially loop-invariant FP values to be considered uniform.
   if (!SE->isSCEVable(V->getType()))
     return false;
-  return (SE->isLoopInvariant(SE->getSCEV(V), TheLoop));
+  const SCEV *S = SE->getSCEV(V);
+  if (SE->isLoopInvariant(S, TheLoop))
+    return true;
+  if (!VF || VF->isScalable())
+    return false;
+  if (VF->isScalar())
+    return true;
+
+  // Rewrite AddRecs in TheLoop to step by VF and check if the expression for
+  // lane 0 matches the expressions for all other lanes.
+  unsigned FixedVF = VF->getKnownMinValue();
+  const SCEV *FirstLaneExpr =
+      SCEVAddRecForUniformityRewriter::rewrite(S, *SE, FixedVF, 0, TheLoop);
+  if (isa<SCEVCouldNotCompute>(FirstLaneExpr))
+    return false;
+
+  // Make sure the expressions for lanes FixedVF-1..1 match the expression for
+  // lane 0. We check lanes in reverse order for compile-time, as frequently
+  // checking the last lane is sufficient to rule out uniformity.
+  return all_of(reverse(seq<unsigned>(1, FixedVF)), [&](unsigned I) {
+    const SCEV *IthLaneExpr =
+        SCEVAddRecForUniformityRewriter::rewrite(S, *SE, FixedVF, I, TheLoop);
+    return FirstLaneExpr == IthLaneExpr;
+  });
 }
 
 /// Find the operand of the GEP that should be checked for consecutive

diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
index a2b5c04dfd149..2fa54b3011dd6 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
@@ -471,11 +471,13 @@ int LoopVectorizationLegality::isConsecutivePtr(Type *AccessTy,
   return 0;
 }
 
-bool LoopVectorizationLegality::isUniform(Value *V) const {
-  return LAI->isUniform(V);
+bool LoopVectorizationLegality::isUniform(
+    Value *V, std::optional<ElementCount> VF) const {
+  return LAI->isUniform(V, VF);
 }
 
-bool LoopVectorizationLegality::isUniformMemOp(Instruction &I) const {
+bool LoopVectorizationLegality::isUniformMemOp(
+    Instruction &I, std::optional<ElementCount> VF) const {
   Value *Ptr = getLoadStorePointerOperand(&I);
   if (!Ptr)
     return false;
@@ -483,7 +485,7 @@ bool LoopVectorizationLegality::isUniformMemOp(Instruction &I) const {
   // stores from being uniform.  The current lowering simply doesn't handle
   // it; in particular, the cost model distinguishes scatter/gather from
   // scalar w/predication, and we currently rely on the scalar path.
-  return isUniform(Ptr) && !blockNeedsPredication(I.getParent());
+  return isUniform(Ptr, VF) && !blockNeedsPredication(I.getParent());
 }
 
 bool LoopVectorizationLegality::canVectorizeOuterLoop() {

diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 9c5caaddb4852..e102efca72649 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -4674,7 +4674,7 @@ void LoopVectorizationCostModel::collectLoopUniforms(ElementCount VF) {
   // Return true if all lanes perform the same memory operation, and we can
   // thus chose to execute only one.
   auto isUniformMemOpUse = [&](Instruction *I) {
-    if (!Legal->isUniformMemOp(*I))
+    if (!Legal->isUniformMemOp(*I, VF))
       return false;
     if (isa<LoadInst>(I))
       // Loading the same address always produces the same result - at least
@@ -6496,7 +6496,7 @@ LoopVectorizationCostModel::getConsecutiveMemOpCost(Instruction *I,
 InstructionCost
 LoopVectorizationCostModel::getUniformMemOpCost(Instruction *I,
                                                 ElementCount VF) {
-  assert(Legal->isUniformMemOp(*I));
+  assert(Legal->isUniformMemOp(*I, VF));
 
   Type *ValTy = getLoadStoreType(I);
   auto *VectorTy = cast<VectorType>(ToVectorTy(ValTy, VF));
@@ -6872,7 +6872,7 @@ void LoopVectorizationCostModel::setCostBasedWideningDecision(ElementCount VF) {
       if (isa<StoreInst>(&I) && isScalarWithPredication(&I, VF))
         NumPredStores++;
 
-      if (Legal->isUniformMemOp(I)) {
+      if (Legal->isUniformMemOp(I, VF)) {
         auto isLegalToScalarize = [&]() {
           if (!VF.isScalable())
             // Scalarization of fixed length vectors "just works".

diff  --git a/llvm/test/Transforms/LoopVectorize/X86/uniform_mem_op.ll b/llvm/test/Transforms/LoopVectorize/X86/uniform_mem_op.ll
index df5931ec925e5..5505b172d1ec0 100644
--- a/llvm/test/Transforms/LoopVectorize/X86/uniform_mem_op.ll
+++ b/llvm/test/Transforms/LoopVectorize/X86/uniform_mem_op.ll
@@ -358,6 +358,9 @@ declare void @init(ptr)
 
 ;; Count the number of bits set in a bit vector -- key point of relevance is
 ;; that the byte load is uniform across 8 iterations at a time.
+;; TODO: At the moment, this is vectorized with VF=4 and UF=4. The load is
+;; considered uniform across VF=4, but should be considered uniform across
+;; VF=8/VF=4,UF=2.
 define i32 @test_count_bits(ptr %test_base) {
 ; CHECK-LABEL: @test_count_bits(
 ; CHECK-NEXT:  entry:
@@ -369,73 +372,75 @@ define i32 @test_count_bits(ptr %test_base) {
 ; 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 i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP50:%.*]], [[VECTOR_BODY]] ]
-; CHECK-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP51:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP36:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP37:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI5:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP38:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI6:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP39:%.*]], [[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i64> [[VEC_IND]], <i64 4, i64 4, i64 4, i64 4>
+; CHECK-NEXT:    [[STEP_ADD1:%.*]] = add <4 x i64> [[STEP_ADD]], <i64 4, i64 4, i64 4, i64 4>
+; CHECK-NEXT:    [[STEP_ADD2:%.*]] = add <4 x i64> [[STEP_ADD1]], <i64 4, i64 4, i64 4, i64 4>
 ; CHECK-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = add i64 [[INDEX]], 1
-; CHECK-NEXT:    [[TMP2:%.*]] = add i64 [[INDEX]], 2
-; CHECK-NEXT:    [[TMP3:%.*]] = add i64 [[INDEX]], 3
-; CHECK-NEXT:    [[TMP4:%.*]] = add i64 [[INDEX]], 4
-; CHECK-NEXT:    [[TMP5:%.*]] = add i64 [[INDEX]], 5
-; CHECK-NEXT:    [[TMP6:%.*]] = add i64 [[INDEX]], 6
-; CHECK-NEXT:    [[TMP7:%.*]] = add i64 [[INDEX]], 7
-; CHECK-NEXT:    [[TMP8:%.*]] = udiv i64 [[TMP0]], 8
-; CHECK-NEXT:    [[TMP9:%.*]] = udiv i64 [[TMP1]], 8
-; CHECK-NEXT:    [[TMP10:%.*]] = udiv i64 [[TMP2]], 8
-; CHECK-NEXT:    [[TMP11:%.*]] = udiv i64 [[TMP3]], 8
-; CHECK-NEXT:    [[TMP12:%.*]] = udiv i64 [[TMP4]], 8
-; CHECK-NEXT:    [[TMP13:%.*]] = udiv i64 [[TMP5]], 8
-; CHECK-NEXT:    [[TMP14:%.*]] = udiv i64 [[TMP6]], 8
-; CHECK-NEXT:    [[TMP15:%.*]] = udiv i64 [[TMP7]], 8
-; CHECK-NEXT:    [[TMP16:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE:%.*]], i64 [[TMP8]]
-; CHECK-NEXT:    [[TMP17:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP9]]
-; CHECK-NEXT:    [[TMP18:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP10]]
-; CHECK-NEXT:    [[TMP19:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP11]]
-; CHECK-NEXT:    [[TMP20:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP12]]
-; CHECK-NEXT:    [[TMP21:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP13]]
-; CHECK-NEXT:    [[TMP22:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP14]]
-; CHECK-NEXT:    [[TMP23:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP15]]
-; CHECK-NEXT:    [[TMP24:%.*]] = load i8, ptr [[TMP16]], align 1
-; CHECK-NEXT:    [[TMP25:%.*]] = load i8, ptr [[TMP17]], align 1
-; CHECK-NEXT:    [[TMP26:%.*]] = load i8, ptr [[TMP18]], align 1
-; CHECK-NEXT:    [[TMP27:%.*]] = load i8, ptr [[TMP19]], align 1
-; CHECK-NEXT:    [[TMP28:%.*]] = insertelement <4 x i8> poison, i8 [[TMP24]], i32 0
-; CHECK-NEXT:    [[TMP29:%.*]] = insertelement <4 x i8> [[TMP28]], i8 [[TMP25]], i32 1
-; CHECK-NEXT:    [[TMP30:%.*]] = insertelement <4 x i8> [[TMP29]], i8 [[TMP26]], i32 2
-; CHECK-NEXT:    [[TMP31:%.*]] = insertelement <4 x i8> [[TMP30]], i8 [[TMP27]], i32 3
-; CHECK-NEXT:    [[TMP32:%.*]] = load i8, ptr [[TMP20]], align 1
-; CHECK-NEXT:    [[TMP33:%.*]] = load i8, ptr [[TMP21]], align 1
-; CHECK-NEXT:    [[TMP34:%.*]] = load i8, ptr [[TMP22]], align 1
-; CHECK-NEXT:    [[TMP35:%.*]] = load i8, ptr [[TMP23]], align 1
-; CHECK-NEXT:    [[TMP36:%.*]] = insertelement <4 x i8> poison, i8 [[TMP32]], i32 0
-; CHECK-NEXT:    [[TMP37:%.*]] = insertelement <4 x i8> [[TMP36]], i8 [[TMP33]], i32 1
-; CHECK-NEXT:    [[TMP38:%.*]] = insertelement <4 x i8> [[TMP37]], i8 [[TMP34]], i32 2
-; CHECK-NEXT:    [[TMP39:%.*]] = insertelement <4 x i8> [[TMP38]], i8 [[TMP35]], i32 3
-; CHECK-NEXT:    [[TMP40:%.*]] = urem <4 x i64> [[VEC_IND]], <i64 8, i64 8, i64 8, i64 8>
-; CHECK-NEXT:    [[TMP41:%.*]] = urem <4 x i64> [[STEP_ADD]], <i64 8, i64 8, i64 8, i64 8>
-; CHECK-NEXT:    [[TMP42:%.*]] = trunc <4 x i64> [[TMP40]] to <4 x i8>
-; CHECK-NEXT:    [[TMP43:%.*]] = trunc <4 x i64> [[TMP41]] to <4 x i8>
-; CHECK-NEXT:    [[TMP44:%.*]] = lshr <4 x i8> [[TMP31]], [[TMP42]]
-; CHECK-NEXT:    [[TMP45:%.*]] = lshr <4 x i8> [[TMP39]], [[TMP43]]
-; CHECK-NEXT:    [[TMP46:%.*]] = and <4 x i8> [[TMP44]], <i8 1, i8 1, i8 1, i8 1>
-; CHECK-NEXT:    [[TMP47:%.*]] = and <4 x i8> [[TMP45]], <i8 1, i8 1, i8 1, i8 1>
-; CHECK-NEXT:    [[TMP48:%.*]] = zext <4 x i8> [[TMP46]] to <4 x i32>
-; CHECK-NEXT:    [[TMP49:%.*]] = zext <4 x i8> [[TMP47]] to <4 x i32>
-; CHECK-NEXT:    [[TMP50]] = add <4 x i32> [[VEC_PHI]], [[TMP48]]
-; CHECK-NEXT:    [[TMP51]] = add <4 x i32> [[VEC_PHI2]], [[TMP49]]
-; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 8
-; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD]], <i64 4, i64 4, i64 4, i64 4>
-; CHECK-NEXT:    [[TMP52:%.*]] = icmp eq i64 [[INDEX_NEXT]], 4096
-; CHECK-NEXT:    br i1 [[TMP52]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP19:![0-9]+]]
+; CHECK-NEXT:    [[TMP1:%.*]] = add i64 [[INDEX]], 4
+; CHECK-NEXT:    [[TMP2:%.*]] = add i64 [[INDEX]], 8
+; CHECK-NEXT:    [[TMP3:%.*]] = add i64 [[INDEX]], 12
+; CHECK-NEXT:    [[TMP4:%.*]] = udiv i64 [[TMP0]], 8
+; CHECK-NEXT:    [[TMP5:%.*]] = udiv i64 [[TMP1]], 8
+; CHECK-NEXT:    [[TMP6:%.*]] = udiv i64 [[TMP2]], 8
+; CHECK-NEXT:    [[TMP7:%.*]] = udiv i64 [[TMP3]], 8
+; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE:%.*]], i64 [[TMP4]]
+; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP5]]
+; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP6]]
+; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i8, ptr [[TEST_BASE]], i64 [[TMP7]]
+; CHECK-NEXT:    [[TMP12:%.*]] = load i8, ptr [[TMP8]], align 1
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i8> poison, i8 [[TMP12]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP13:%.*]] = load i8, ptr [[TMP9]], align 1
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT7:%.*]] = insertelement <4 x i8> poison, i8 [[TMP13]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT8:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT7]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP14:%.*]] = load i8, ptr [[TMP10]], align 1
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT9:%.*]] = insertelement <4 x i8> poison, i8 [[TMP14]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT10:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT9]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP15:%.*]] = load i8, ptr [[TMP11]], align 1
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT11:%.*]] = insertelement <4 x i8> poison, i8 [[TMP15]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT12:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT11]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP16:%.*]] = urem <4 x i64> [[VEC_IND]], <i64 8, i64 8, i64 8, i64 8>
+; CHECK-NEXT:    [[TMP17:%.*]] = urem <4 x i64> [[STEP_ADD]], <i64 8, i64 8, i64 8, i64 8>
+; CHECK-NEXT:    [[TMP18:%.*]] = urem <4 x i64> [[STEP_ADD1]], <i64 8, i64 8, i64 8, i64 8>
+; CHECK-NEXT:    [[TMP19:%.*]] = urem <4 x i64> [[STEP_ADD2]], <i64 8, i64 8, i64 8, i64 8>
+; CHECK-NEXT:    [[TMP20:%.*]] = trunc <4 x i64> [[TMP16]] to <4 x i8>
+; CHECK-NEXT:    [[TMP21:%.*]] = trunc <4 x i64> [[TMP17]] to <4 x i8>
+; CHECK-NEXT:    [[TMP22:%.*]] = trunc <4 x i64> [[TMP18]] to <4 x i8>
+; CHECK-NEXT:    [[TMP23:%.*]] = trunc <4 x i64> [[TMP19]] to <4 x i8>
+; CHECK-NEXT:    [[TMP24:%.*]] = lshr <4 x i8> [[BROADCAST_SPLAT]], [[TMP20]]
+; CHECK-NEXT:    [[TMP25:%.*]] = lshr <4 x i8> [[BROADCAST_SPLAT8]], [[TMP21]]
+; CHECK-NEXT:    [[TMP26:%.*]] = lshr <4 x i8> [[BROADCAST_SPLAT10]], [[TMP22]]
+; CHECK-NEXT:    [[TMP27:%.*]] = lshr <4 x i8> [[BROADCAST_SPLAT12]], [[TMP23]]
+; CHECK-NEXT:    [[TMP28:%.*]] = and <4 x i8> [[TMP24]], <i8 1, i8 1, i8 1, i8 1>
+; CHECK-NEXT:    [[TMP29:%.*]] = and <4 x i8> [[TMP25]], <i8 1, i8 1, i8 1, i8 1>
+; CHECK-NEXT:    [[TMP30:%.*]] = and <4 x i8> [[TMP26]], <i8 1, i8 1, i8 1, i8 1>
+; CHECK-NEXT:    [[TMP31:%.*]] = and <4 x i8> [[TMP27]], <i8 1, i8 1, i8 1, i8 1>
+; CHECK-NEXT:    [[TMP32:%.*]] = zext <4 x i8> [[TMP28]] to <4 x i32>
+; CHECK-NEXT:    [[TMP33:%.*]] = zext <4 x i8> [[TMP29]] to <4 x i32>
+; CHECK-NEXT:    [[TMP34:%.*]] = zext <4 x i8> [[TMP30]] to <4 x i32>
+; CHECK-NEXT:    [[TMP35:%.*]] = zext <4 x i8> [[TMP31]] to <4 x i32>
+; CHECK-NEXT:    [[TMP36]] = add <4 x i32> [[VEC_PHI]], [[TMP32]]
+; CHECK-NEXT:    [[TMP37]] = add <4 x i32> [[VEC_PHI4]], [[TMP33]]
+; CHECK-NEXT:    [[TMP38]] = add <4 x i32> [[VEC_PHI5]], [[TMP34]]
+; CHECK-NEXT:    [[TMP39]] = add <4 x i32> [[VEC_PHI6]], [[TMP35]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 16
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[STEP_ADD2]], <i64 4, i64 4, i64 4, i64 4>
+; CHECK-NEXT:    [[TMP40:%.*]] = icmp eq i64 [[INDEX_NEXT]], 4096
+; CHECK-NEXT:    br i1 [[TMP40]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP19:![0-9]+]]
 ; CHECK:       middle.block:
-; CHECK-NEXT:    [[BIN_RDX:%.*]] = add <4 x i32> [[TMP51]], [[TMP50]]
-; CHECK-NEXT:    [[TMP53:%.*]] = call i32 @llvm.vector.reduce.add.v4i32(<4 x i32> [[BIN_RDX]])
+; CHECK-NEXT:    [[BIN_RDX:%.*]] = add <4 x i32> [[TMP37]], [[TMP36]]
+; CHECK-NEXT:    [[BIN_RDX13:%.*]] = add <4 x i32> [[TMP38]], [[BIN_RDX]]
+; CHECK-NEXT:    [[BIN_RDX14:%.*]] = add <4 x i32> [[TMP39]], [[BIN_RDX13]]
+; CHECK-NEXT:    [[TMP41:%.*]] = call i32 @llvm.vector.reduce.add.v4i32(<4 x i32> [[BIN_RDX14]])
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 4096, 4096
 ; CHECK-NEXT:    br i1 [[CMP_N]], label [[LOOP_EXIT:%.*]], label [[SCALAR_PH]]
 ; CHECK:       scalar.ph:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ 4096, [[MIDDLE_BLOCK]] ], [ 0, [[ENTRY:%.*]] ]
-; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[TMP53]], [[MIDDLE_BLOCK]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[TMP41]], [[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    br label [[LOOP:%.*]]
 ; CHECK:       loop:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
@@ -453,7 +458,7 @@ define i32 @test_count_bits(ptr %test_base) {
 ; CHECK-NEXT:    [[EXIT:%.*]] = icmp ugt i64 [[IV]], 4094
 ; CHECK-NEXT:    br i1 [[EXIT]], label [[LOOP_EXIT]], label [[LOOP]], !llvm.loop [[LOOP20:![0-9]+]]
 ; CHECK:       loop_exit:
-; CHECK-NEXT:    [[ACCUM_NEXT_LCSSA:%.*]] = phi i32 [ [[ACCUM_NEXT]], [[LOOP]] ], [ [[TMP53]], [[MIDDLE_BLOCK]] ]
+; CHECK-NEXT:    [[ACCUM_NEXT_LCSSA:%.*]] = phi i32 [ [[ACCUM_NEXT]], [[LOOP]] ], [ [[TMP41]], [[MIDDLE_BLOCK]] ]
 ; CHECK-NEXT:    ret i32 [[ACCUM_NEXT_LCSSA]]
 ;
 entry:

diff  --git a/llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll b/llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll
index 461e3a0e0278b..9831135b1d486 100644
--- a/llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll
+++ b/llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll
@@ -64,7 +64,7 @@ define void @f() {
 ; CHECK-NEXT:    store i8 10, ptr [[TMP1]], align 1
 ; CHECK-NEXT:    [[IV_NEXT]] = add nsw i32 [[IV]], 1
 ; CHECK-NEXT:    [[EC:%.*]] = icmp eq i32 [[IV_NEXT]], 500
-; CHECK-NEXT:    br i1 [[EC]], label [[EXIT]], label [[LOOP]], !llvm.loop [[LOOP7:![0-9]+]]
+; CHECK-NEXT:    br i1 [[EC]], label [[EXIT]], label [[LOOP]], !llvm.loop [[LOOP8:![0-9]+]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret void
 ;

diff  --git a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1.ll b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1.ll
index 4dbfe2e433681..0d826245559e7 100644
--- a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1.ll
+++ b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1.ll
@@ -63,6 +63,7 @@ exit:
 }
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[iv/2] + 42;
+; A[iv/2] is uniform for VF=2.
 define void @ld_div2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; CHECK-LABEL: define void @ld_div2_step1_start0_ind1
 ; CHECK-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -72,25 +73,19 @@ define void @ld_div2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; 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 <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = udiv <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; CHECK-NEXT:    [[TMP2:%.*]] = extractelement <2 x i64> [[TMP1]], i32 0
-; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
-; CHECK-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP1]], i32 1
-; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; CHECK-NEXT:    [[TMP6:%.*]] = load i64, ptr [[TMP3]], align 8
-; CHECK-NEXT:    [[TMP7:%.*]] = load i64, ptr [[TMP5]], align 8
-; CHECK-NEXT:    [[TMP8:%.*]] = insertelement <2 x i64> poison, i64 [[TMP6]], i32 0
-; CHECK-NEXT:    [[TMP9:%.*]] = insertelement <2 x i64> [[TMP8]], i64 [[TMP7]], i32 1
-; CHECK-NEXT:    [[TMP10:%.*]] = add nsw <2 x i64> [[TMP9]], <i64 42, i64 42>
-; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; CHECK-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i64, ptr [[TMP11]], i32 0
-; CHECK-NEXT:    store <2 x i64> [[TMP10]], ptr [[TMP12]], align 8
+; CHECK-NEXT:    [[TMP1:%.*]] = udiv i64 [[TMP0]], 2
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP1]]
+; CHECK-NEXT:    [[TMP3:%.*]] = load i64, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP3]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP4:%.*]] = add nsw <2 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42>
+; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[TMP5]], i32 0
+; CHECK-NEXT:    store <2 x i64> [[TMP4]], ptr [[TMP6]], align 8
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
-; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; CHECK-NEXT:    [[TMP13:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; CHECK-NEXT:    br i1 [[TMP13]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; CHECK-NEXT:    br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; CHECK:       middle.block:
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; CHECK-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]

diff  --git a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_and.ll b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_and.ll
index be9a87be94610..3fb1bc7b687bf 100644
--- a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_and.ll
+++ b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_and.ll
@@ -63,6 +63,7 @@ exit:
 }
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[iv&-2] + 42;
+; A[iv&-2] is uniform for VF=2.
 define void @ld_and_neg2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; CHECK-LABEL: define void @ld_and_neg2_step1_start0_ind1
 ; CHECK-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -72,25 +73,19 @@ define void @ld_and_neg2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; 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 <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = and <2 x i64> [[VEC_IND]], <i64 -2, i64 -2>
-; CHECK-NEXT:    [[TMP2:%.*]] = extractelement <2 x i64> [[TMP1]], i32 0
-; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
-; CHECK-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP1]], i32 1
-; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; CHECK-NEXT:    [[TMP6:%.*]] = load i64, ptr [[TMP3]], align 8
-; CHECK-NEXT:    [[TMP7:%.*]] = load i64, ptr [[TMP5]], align 8
-; CHECK-NEXT:    [[TMP8:%.*]] = insertelement <2 x i64> poison, i64 [[TMP6]], i32 0
-; CHECK-NEXT:    [[TMP9:%.*]] = insertelement <2 x i64> [[TMP8]], i64 [[TMP7]], i32 1
-; CHECK-NEXT:    [[TMP10:%.*]] = add nsw <2 x i64> [[TMP9]], <i64 42, i64 42>
-; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; CHECK-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i64, ptr [[TMP11]], i32 0
-; CHECK-NEXT:    store <2 x i64> [[TMP10]], ptr [[TMP12]], align 8
+; CHECK-NEXT:    [[TMP1:%.*]] = and i64 [[TMP0]], -2
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP1]]
+; CHECK-NEXT:    [[TMP3:%.*]] = load i64, ptr [[TMP2]], align 8
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP3]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP4:%.*]] = add nsw <2 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42>
+; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[TMP5]], i32 0
+; CHECK-NEXT:    store <2 x i64> [[TMP4]], ptr [[TMP6]], align 8
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
-; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; CHECK-NEXT:    [[TMP13:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; CHECK-NEXT:    br i1 [[TMP13]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; CHECK-NEXT:    br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; CHECK:       middle.block:
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; CHECK-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]

diff  --git a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_div_urem.ll b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_div_urem.ll
index 42f6df8ae1d78..ff1a6479faa2b 100644
--- a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_div_urem.ll
+++ b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_div_urem.ll
@@ -4,6 +4,7 @@
 ; Tests for checking uniformity within a VF.
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[(iv/2)%3];
+; A[(iv/2)%3] is not uniform for VF=8.
 define void @ld_div2_urem3_1(ptr noalias %A, ptr noalias %B) {
 ; CHECK-LABEL: define void @ld_div2_urem3_1
 ; CHECK-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -281,6 +282,7 @@ exit:
 }
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[(iv/8)%3];
+; A[(iv/8)%3] is uniform for VF=8.
 define void @ld_div8_urem3(ptr noalias %A, ptr noalias %B) {
 ; CHECK-LABEL: define void @ld_div8_urem3
 ; CHECK-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -290,50 +292,20 @@ define void @ld_div8_urem3(ptr noalias %A, ptr noalias %B) {
 ; 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 <8 x i64> [ <i64 0, i64 1, i64 2, i64 3, i64 4, i64 5, i64 6, i64 7>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = udiv <8 x i64> [[VEC_IND]], <i64 8, i64 8, i64 8, i64 8, i64 8, i64 8, i64 8, i64 8>
-; CHECK-NEXT:    [[TMP2:%.*]] = urem <8 x i64> [[TMP1]], <i64 3, i64 3, i64 3, i64 3, i64 3, i64 3, i64 3, i64 3>
-; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <8 x i64> [[TMP2]], i32 0
-; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP3]]
-; CHECK-NEXT:    [[TMP5:%.*]] = extractelement <8 x i64> [[TMP2]], i32 1
-; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP5]]
-; CHECK-NEXT:    [[TMP7:%.*]] = extractelement <8 x i64> [[TMP2]], i32 2
-; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP7]]
-; CHECK-NEXT:    [[TMP9:%.*]] = extractelement <8 x i64> [[TMP2]], i32 3
-; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP9]]
-; CHECK-NEXT:    [[TMP11:%.*]] = extractelement <8 x i64> [[TMP2]], i32 4
-; CHECK-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP11]]
-; CHECK-NEXT:    [[TMP13:%.*]] = extractelement <8 x i64> [[TMP2]], i32 5
-; CHECK-NEXT:    [[TMP14:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP13]]
-; CHECK-NEXT:    [[TMP15:%.*]] = extractelement <8 x i64> [[TMP2]], i32 6
-; CHECK-NEXT:    [[TMP16:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP15]]
-; CHECK-NEXT:    [[TMP17:%.*]] = extractelement <8 x i64> [[TMP2]], i32 7
-; CHECK-NEXT:    [[TMP18:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP17]]
-; CHECK-NEXT:    [[TMP19:%.*]] = load i64, ptr [[TMP4]], align 8
-; CHECK-NEXT:    [[TMP20:%.*]] = load i64, ptr [[TMP6]], align 8
-; CHECK-NEXT:    [[TMP21:%.*]] = load i64, ptr [[TMP8]], align 8
-; CHECK-NEXT:    [[TMP22:%.*]] = load i64, ptr [[TMP10]], align 8
-; CHECK-NEXT:    [[TMP23:%.*]] = load i64, ptr [[TMP12]], align 8
-; CHECK-NEXT:    [[TMP24:%.*]] = load i64, ptr [[TMP14]], align 8
-; CHECK-NEXT:    [[TMP25:%.*]] = load i64, ptr [[TMP16]], align 8
-; CHECK-NEXT:    [[TMP26:%.*]] = load i64, ptr [[TMP18]], align 8
-; CHECK-NEXT:    [[TMP27:%.*]] = insertelement <8 x i64> poison, i64 [[TMP19]], i32 0
-; CHECK-NEXT:    [[TMP28:%.*]] = insertelement <8 x i64> [[TMP27]], i64 [[TMP20]], i32 1
-; CHECK-NEXT:    [[TMP29:%.*]] = insertelement <8 x i64> [[TMP28]], i64 [[TMP21]], i32 2
-; CHECK-NEXT:    [[TMP30:%.*]] = insertelement <8 x i64> [[TMP29]], i64 [[TMP22]], i32 3
-; CHECK-NEXT:    [[TMP31:%.*]] = insertelement <8 x i64> [[TMP30]], i64 [[TMP23]], i32 4
-; CHECK-NEXT:    [[TMP32:%.*]] = insertelement <8 x i64> [[TMP31]], i64 [[TMP24]], i32 5
-; CHECK-NEXT:    [[TMP33:%.*]] = insertelement <8 x i64> [[TMP32]], i64 [[TMP25]], i32 6
-; CHECK-NEXT:    [[TMP34:%.*]] = insertelement <8 x i64> [[TMP33]], i64 [[TMP26]], i32 7
-; CHECK-NEXT:    [[TMP35:%.*]] = add nsw <8 x i64> [[TMP34]], <i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42>
-; CHECK-NEXT:    [[TMP36:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; CHECK-NEXT:    [[TMP37:%.*]] = getelementptr inbounds i64, ptr [[TMP36]], i32 0
-; CHECK-NEXT:    store <8 x i64> [[TMP35]], ptr [[TMP37]], align 8
+; CHECK-NEXT:    [[TMP1:%.*]] = udiv i64 [[TMP0]], 8
+; CHECK-NEXT:    [[TMP2:%.*]] = urem i64 [[TMP1]], 3
+; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
+; CHECK-NEXT:    [[TMP4:%.*]] = load i64, ptr [[TMP3]], align 8
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <8 x i64> poison, i64 [[TMP4]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <8 x i64> [[BROADCAST_SPLATINSERT]], <8 x i64> poison, <8 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP5:%.*]] = add nsw <8 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42>
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i64, ptr [[TMP6]], i32 0
+; CHECK-NEXT:    store <8 x i64> [[TMP5]], ptr [[TMP7]], align 8
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 8
-; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <8 x i64> [[VEC_IND]], <i64 8, i64 8, i64 8, i64 8, i64 8, i64 8, i64 8, i64 8>
-; CHECK-NEXT:    [[TMP38:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; CHECK-NEXT:    br i1 [[TMP38]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; CHECK-NEXT:    br i1 [[TMP8]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
 ; CHECK:       middle.block:
 ; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; CHECK-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]

diff  --git a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_lshr.ll b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_lshr.ll
index 8c27b0b184c3b..72d41ffd0f407 100644
--- a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_lshr.ll
+++ b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction1_lshr.ll
@@ -104,6 +104,7 @@ exit:
 }
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[iv>>1] + 42;
+; A[iv>>1] is uniform for VF=2 but not VF=4.
 define void @ld_lshr1_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF2-LABEL: define void @ld_lshr1_step1_start0_ind1
 ; VF2-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -113,25 +114,19 @@ define void @ld_lshr1_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF2-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; VF2:       vector.body:
 ; VF2-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; VF2-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; VF2-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; VF2-NEXT:    [[TMP1:%.*]] = lshr <2 x i64> [[VEC_IND]], <i64 1, i64 1>
-; VF2-NEXT:    [[TMP2:%.*]] = extractelement <2 x i64> [[TMP1]], i32 0
-; VF2-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
-; VF2-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP1]], i32 1
-; VF2-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; VF2-NEXT:    [[TMP6:%.*]] = load i64, ptr [[TMP3]], align 8
-; VF2-NEXT:    [[TMP7:%.*]] = load i64, ptr [[TMP5]], align 8
-; VF2-NEXT:    [[TMP8:%.*]] = insertelement <2 x i64> poison, i64 [[TMP6]], i32 0
-; VF2-NEXT:    [[TMP9:%.*]] = insertelement <2 x i64> [[TMP8]], i64 [[TMP7]], i32 1
-; VF2-NEXT:    [[TMP10:%.*]] = add nsw <2 x i64> [[TMP9]], <i64 42, i64 42>
-; VF2-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; VF2-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i64, ptr [[TMP11]], i32 0
-; VF2-NEXT:    store <2 x i64> [[TMP10]], ptr [[TMP12]], align 8
+; VF2-NEXT:    [[TMP1:%.*]] = lshr i64 [[TMP0]], 1
+; VF2-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP1]]
+; VF2-NEXT:    [[TMP3:%.*]] = load i64, ptr [[TMP2]], align 8
+; VF2-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP3]], i64 0
+; VF2-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; VF2-NEXT:    [[TMP4:%.*]] = add nsw <2 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42>
+; VF2-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; VF2-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[TMP5]], i32 0
+; VF2-NEXT:    store <2 x i64> [[TMP4]], ptr [[TMP6]], align 8
 ; VF2-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
-; VF2-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP13:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; VF2-NEXT:    br i1 [[TMP13]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; VF2-NEXT:    [[TMP7:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; VF2-NEXT:    br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; VF2:       middle.block:
 ; VF2-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; VF2-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]
@@ -225,6 +220,7 @@ exit:
 }
 
 ; for (iv = 0 ; ; iv += 1) B[iv] = A[iv>>2] + 42;
+; A[iv>>2] is uniform for VF=2 and VF=4.
 define void @ld_lshr2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF2-LABEL: define void @ld_lshr2_step1_start0_ind1
 ; VF2-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -234,25 +230,19 @@ define void @ld_lshr2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF2-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; VF2:       vector.body:
 ; VF2-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; VF2-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; VF2-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; VF2-NEXT:    [[TMP1:%.*]] = lshr <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP2:%.*]] = extractelement <2 x i64> [[TMP1]], i32 0
-; VF2-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
-; VF2-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP1]], i32 1
-; VF2-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; VF2-NEXT:    [[TMP6:%.*]] = load i64, ptr [[TMP3]], align 8
-; VF2-NEXT:    [[TMP7:%.*]] = load i64, ptr [[TMP5]], align 8
-; VF2-NEXT:    [[TMP8:%.*]] = insertelement <2 x i64> poison, i64 [[TMP6]], i32 0
-; VF2-NEXT:    [[TMP9:%.*]] = insertelement <2 x i64> [[TMP8]], i64 [[TMP7]], i32 1
-; VF2-NEXT:    [[TMP10:%.*]] = add nsw <2 x i64> [[TMP9]], <i64 42, i64 42>
-; VF2-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; VF2-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i64, ptr [[TMP11]], i32 0
-; VF2-NEXT:    store <2 x i64> [[TMP10]], ptr [[TMP12]], align 8
+; VF2-NEXT:    [[TMP1:%.*]] = lshr i64 [[TMP0]], 2
+; VF2-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP1]]
+; VF2-NEXT:    [[TMP3:%.*]] = load i64, ptr [[TMP2]], align 8
+; VF2-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP3]], i64 0
+; VF2-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; VF2-NEXT:    [[TMP4:%.*]] = add nsw <2 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42>
+; VF2-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; VF2-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[TMP5]], i32 0
+; VF2-NEXT:    store <2 x i64> [[TMP4]], ptr [[TMP6]], align 8
 ; VF2-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
-; VF2-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP13:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; VF2-NEXT:    br i1 [[TMP13]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; VF2-NEXT:    [[TMP7:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; VF2-NEXT:    br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
 ; VF2:       middle.block:
 ; VF2-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; VF2-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]
@@ -281,33 +271,19 @@ define void @ld_lshr2_step1_start0_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF4-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; VF4:       vector.body:
 ; VF4-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; VF4-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; VF4-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; VF4-NEXT:    [[TMP1:%.*]] = lshr <4 x i64> [[VEC_IND]], <i64 2, i64 2, i64 2, i64 2>
-; VF4-NEXT:    [[TMP2:%.*]] = extractelement <4 x i64> [[TMP1]], i32 0
-; VF4-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP2]]
-; VF4-NEXT:    [[TMP4:%.*]] = extractelement <4 x i64> [[TMP1]], i32 1
-; VF4-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; VF4-NEXT:    [[TMP6:%.*]] = extractelement <4 x i64> [[TMP1]], i32 2
-; VF4-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP6]]
-; VF4-NEXT:    [[TMP8:%.*]] = extractelement <4 x i64> [[TMP1]], i32 3
-; VF4-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP8]]
-; VF4-NEXT:    [[TMP10:%.*]] = load i64, ptr [[TMP3]], align 8
-; VF4-NEXT:    [[TMP11:%.*]] = load i64, ptr [[TMP5]], align 8
-; VF4-NEXT:    [[TMP12:%.*]] = load i64, ptr [[TMP7]], align 8
-; VF4-NEXT:    [[TMP13:%.*]] = load i64, ptr [[TMP9]], align 8
-; VF4-NEXT:    [[TMP14:%.*]] = insertelement <4 x i64> poison, i64 [[TMP10]], i32 0
-; VF4-NEXT:    [[TMP15:%.*]] = insertelement <4 x i64> [[TMP14]], i64 [[TMP11]], i32 1
-; VF4-NEXT:    [[TMP16:%.*]] = insertelement <4 x i64> [[TMP15]], i64 [[TMP12]], i32 2
-; VF4-NEXT:    [[TMP17:%.*]] = insertelement <4 x i64> [[TMP16]], i64 [[TMP13]], i32 3
-; VF4-NEXT:    [[TMP18:%.*]] = add nsw <4 x i64> [[TMP17]], <i64 42, i64 42, i64 42, i64 42>
-; VF4-NEXT:    [[TMP19:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; VF4-NEXT:    [[TMP20:%.*]] = getelementptr inbounds i64, ptr [[TMP19]], i32 0
-; VF4-NEXT:    store <4 x i64> [[TMP18]], ptr [[TMP20]], align 8
+; VF4-NEXT:    [[TMP1:%.*]] = lshr i64 [[TMP0]], 2
+; VF4-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP1]]
+; VF4-NEXT:    [[TMP3:%.*]] = load i64, ptr [[TMP2]], align 8
+; VF4-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[TMP3]], i64 0
+; VF4-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
+; VF4-NEXT:    [[TMP4:%.*]] = add nsw <4 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42, i64 42, i64 42>
+; VF4-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
+; VF4-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i64, ptr [[TMP5]], i32 0
+; VF4-NEXT:    store <4 x i64> [[TMP4]], ptr [[TMP6]], align 8
 ; VF4-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4
-; VF4-NEXT:    [[VEC_IND_NEXT]] = add <4 x i64> [[VEC_IND]], <i64 4, i64 4, i64 4, i64 4>
-; VF4-NEXT:    [[TMP21:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; VF4-NEXT:    br i1 [[TMP21]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
+; VF4-NEXT:    [[TMP7:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; VF4-NEXT:    br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
 ; VF4:       middle.block:
 ; VF4-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; VF4-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]
@@ -880,6 +856,7 @@ exit:
 }
 
 ; for (iv = 1 ; ; iv += 1) B[iv] = A[iv>>1] + 42;
+; A[iv>>1] not uniform for VF=2 due to alignment (iv starts at 1).
 define void @ld_lshr1_step1_start1_ind1(ptr noalias %A, ptr noalias %B) {
 ; VF2-LABEL: define void @ld_lshr1_step1_start1_ind1
 ; VF2-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {

diff  --git a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction2.ll b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction2.ll
index 5ac38497f8a11..0461718455751 100644
--- a/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction2.ll
+++ b/llvm/test/Transforms/LoopVectorize/uniform_across_vf_induction2.ll
@@ -146,6 +146,7 @@ exit:
 }
 
 ; for (iv = 0, iv2 = 0 ; ; iv += 1, iv2 += 1) B[iv] = A[iv/2 + iv2/2] + 42;
+; A[iv/2 + iv2/2] is uniform for VF=2 but not for VF=4.
 define void @ld_div2_step1_start0_ind2(ptr noalias %A, ptr noalias %B) {
 ; VF2-LABEL: define void @ld_div2_step1_start0_ind2
 ; VF2-SAME: (ptr noalias [[A:%.*]], ptr noalias [[B:%.*]]) {
@@ -155,29 +156,22 @@ define void @ld_div2_step1_start0_ind2(ptr noalias %A, ptr noalias %B) {
 ; VF2-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; VF2:       vector.body:
 ; VF2-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; VF2-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
-; VF2-NEXT:    [[VEC_IND2:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT3:%.*]], [[VECTOR_BODY]] ]
 ; VF2-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
-; VF2-NEXT:    [[TMP1:%.*]] = udiv <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP2:%.*]] = udiv <2 x i64> [[VEC_IND2]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP3:%.*]] = add <2 x i64> [[TMP1]], [[TMP2]]
-; VF2-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP3]], i32 0
+; VF2-NEXT:    [[TMP1:%.*]] = add i64 [[INDEX]], 0
+; VF2-NEXT:    [[TMP2:%.*]] = udiv i64 [[TMP1]], 2
+; VF2-NEXT:    [[TMP3:%.*]] = udiv i64 [[TMP0]], 2
+; VF2-NEXT:    [[TMP4:%.*]] = add i64 [[TMP2]], [[TMP3]]
 ; VF2-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP4]]
-; VF2-NEXT:    [[TMP6:%.*]] = extractelement <2 x i64> [[TMP3]], i32 1
-; VF2-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP6]]
-; VF2-NEXT:    [[TMP8:%.*]] = load i64, ptr [[TMP5]], align 8
-; VF2-NEXT:    [[TMP9:%.*]] = load i64, ptr [[TMP7]], align 8
-; VF2-NEXT:    [[TMP10:%.*]] = insertelement <2 x i64> poison, i64 [[TMP8]], i32 0
-; VF2-NEXT:    [[TMP11:%.*]] = insertelement <2 x i64> [[TMP10]], i64 [[TMP9]], i32 1
-; VF2-NEXT:    [[TMP12:%.*]] = add nsw <2 x i64> [[TMP11]], <i64 42, i64 42>
-; VF2-NEXT:    [[TMP13:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP0]]
-; VF2-NEXT:    [[TMP14:%.*]] = getelementptr inbounds i64, ptr [[TMP13]], i32 0
-; VF2-NEXT:    store <2 x i64> [[TMP12]], ptr [[TMP14]], align 8
+; VF2-NEXT:    [[TMP6:%.*]] = load i64, ptr [[TMP5]], align 8
+; VF2-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i64> poison, i64 [[TMP6]], i64 0
+; VF2-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT]], <2 x i64> poison, <2 x i32> zeroinitializer
+; VF2-NEXT:    [[TMP7:%.*]] = add nsw <2 x i64> [[BROADCAST_SPLAT]], <i64 42, i64 42>
+; VF2-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i64, ptr [[B]], i64 [[TMP1]]
+; VF2-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i64, ptr [[TMP8]], i32 0
+; VF2-NEXT:    store <2 x i64> [[TMP7]], ptr [[TMP9]], align 8
 ; VF2-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
-; VF2-NEXT:    [[VEC_IND_NEXT]] = add <2 x i64> [[VEC_IND]], <i64 2, i64 2>
-; VF2-NEXT:    [[VEC_IND_NEXT3]] = add <2 x i64> [[VEC_IND2]], <i64 2, i64 2>
-; VF2-NEXT:    [[TMP15:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
-; VF2-NEXT:    br i1 [[TMP15]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; VF2-NEXT:    [[TMP10:%.*]] = icmp eq i64 [[INDEX_NEXT]], 1000
+; VF2-NEXT:    br i1 [[TMP10]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; VF2:       middle.block:
 ; VF2-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1000, 1000
 ; VF2-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]


        


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