Intermediate changes

commit_hash:2ec2671384dd8e604d41bc5c52c2f7858e4afea6

1 files changed, 0 insertions, 2362 deletions

diff --git a/contrib/libs/llvm14/lib/Analysis/LoopAccessAnalysis.cpp b/contrib/libs/llvm14/lib/Analysis/LoopAccessAnalysis.cpp
deleted file mode 100644
index 2ab78d2b7ee..00000000000
--- a/contrib/libs/llvm14/lib/Analysis/LoopAccessAnalysis.cpp
+++ /dev/null
@@ -1,2362 +0,0 @@
-//===- LoopAccessAnalysis.cpp - Loop Access Analysis Implementation --------==//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// The implementation for the loop memory dependence that was originally
-// developed for the loop vectorizer.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Analysis/LoopAccessAnalysis.h"
-#include "llvm/ADT/APInt.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/EquivalenceClasses.h"
-#include "llvm/ADT/PointerIntPair.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SetVector.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/iterator_range.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/AliasSetTracker.h"
-#include "llvm/Analysis/LoopAnalysisManager.h"
-#include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/MemoryLocation.h"
-#include "llvm/Analysis/OptimizationRemarkEmitter.h"
-#include "llvm/Analysis/ScalarEvolution.h"
-#include "llvm/Analysis/ScalarEvolutionExpressions.h"
-#include "llvm/Analysis/TargetLibraryInfo.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/Analysis/VectorUtils.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DebugLoc.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/DiagnosticInfo.h"
-#include "llvm/IR/Dominators.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/InstrTypes.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/Operator.h"
-#include "llvm/IR/PassManager.h"
-#include "llvm/IR/Type.h"
-#include "llvm/IR/Value.h"
-#include "llvm/IR/ValueHandle.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/raw_ostream.h"
-#include <algorithm>
-#include <cassert>
-#include <cstdint>
-#include <cstdlib>
-#include <iterator>
-#include <utility>
-#include <vector>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "loop-accesses"
-
-static cl::opt<unsigned, true>
-VectorizationFactor("force-vector-width", cl::Hidden,
-                    cl::desc("Sets the SIMD width. Zero is autoselect."),
-                    cl::location(VectorizerParams::VectorizationFactor));
-unsigned VectorizerParams::VectorizationFactor;
-
-static cl::opt<unsigned, true>
-VectorizationInterleave("force-vector-interleave", cl::Hidden,
-                        cl::desc("Sets the vectorization interleave count. "
-                                 "Zero is autoselect."),
-                        cl::location(
-                            VectorizerParams::VectorizationInterleave));
-unsigned VectorizerParams::VectorizationInterleave;
-
-static cl::opt<unsigned, true> RuntimeMemoryCheckThreshold(
-    "runtime-memory-check-threshold", cl::Hidden,
-    cl::desc("When performing memory disambiguation checks at runtime do not "
-             "generate more than this number of comparisons (default = 8)."),
-    cl::location(VectorizerParams::RuntimeMemoryCheckThreshold), cl::init(8));
-unsigned VectorizerParams::RuntimeMemoryCheckThreshold;
-
-/// The maximum iterations used to merge memory checks
-static cl::opt<unsigned> MemoryCheckMergeThreshold(
-    "memory-check-merge-threshold", cl::Hidden,
-    cl::desc("Maximum number of comparisons done when trying to merge "
-             "runtime memory checks. (default = 100)"),
-    cl::init(100));
-
-/// Maximum SIMD width.
-const unsigned VectorizerParams::MaxVectorWidth = 64;
-
-/// We collect dependences up to this threshold.
-static cl::opt<unsigned>
-    MaxDependences("max-dependences", cl::Hidden,
-                   cl::desc("Maximum number of dependences collected by "
-                            "loop-access analysis (default = 100)"),
-                   cl::init(100));
-
-/// This enables versioning on the strides of symbolically striding memory
-/// accesses in code like the following.
-///   for (i = 0; i < N; ++i)
-///     A[i * Stride1] += B[i * Stride2] ...
-///
-/// Will be roughly translated to
-///    if (Stride1 == 1 && Stride2 == 1) {
-///      for (i = 0; i < N; i+=4)
-///       A[i:i+3] += ...
-///    } else
-///      ...
-static cl::opt<bool> EnableMemAccessVersioning(
-    "enable-mem-access-versioning", cl::init(true), cl::Hidden,
-    cl::desc("Enable symbolic stride memory access versioning"));
-
-/// Enable store-to-load forwarding conflict detection. This option can
-/// be disabled for correctness testing.
-static cl::opt<bool> EnableForwardingConflictDetection(
-    "store-to-load-forwarding-conflict-detection", cl::Hidden,
-    cl::desc("Enable conflict detection in loop-access analysis"),
-    cl::init(true));
-
-bool VectorizerParams::isInterleaveForced() {
-  return ::VectorizationInterleave.getNumOccurrences() > 0;
-}
-
-Value *llvm::stripIntegerCast(Value *V) {
-  if (auto *CI = dyn_cast<CastInst>(V))
-    if (CI->getOperand(0)->getType()->isIntegerTy())
-      return CI->getOperand(0);
-  return V;
-}
-
-const SCEV *llvm::replaceSymbolicStrideSCEV(PredicatedScalarEvolution &PSE,
-                                            const ValueToValueMap &PtrToStride,
-                                            Value *Ptr) {
-  const SCEV *OrigSCEV = PSE.getSCEV(Ptr);
-
-  // If there is an entry in the map return the SCEV of the pointer with the
-  // symbolic stride replaced by one.
-  ValueToValueMap::const_iterator SI = PtrToStride.find(Ptr);
-  if (SI == PtrToStride.end())
-    // For a non-symbolic stride, just return the original expression.
-    return OrigSCEV;
-
-  Value *StrideVal = stripIntegerCast(SI->second);
-
-  ScalarEvolution *SE = PSE.getSE();
-  const auto *U = cast<SCEVUnknown>(SE->getSCEV(StrideVal));
-  const auto *CT =
-    static_cast<const SCEVConstant *>(SE->getOne(StrideVal->getType()));
-
-  PSE.addPredicate(*SE->getEqualPredicate(U, CT));
-  auto *Expr = PSE.getSCEV(Ptr);
-
-  LLVM_DEBUG(dbgs() << "LAA: Replacing SCEV: " << *OrigSCEV
-	     << " by: " << *Expr << "\n");
-  return Expr;
-}
-
-RuntimeCheckingPtrGroup::RuntimeCheckingPtrGroup(
-    unsigned Index, RuntimePointerChecking &RtCheck)
-    : High(RtCheck.Pointers[Index].End), Low(RtCheck.Pointers[Index].Start),
-      AddressSpace(RtCheck.Pointers[Index]
-                       .PointerValue->getType()
-                       ->getPointerAddressSpace()) {
-  Members.push_back(Index);
-}
-
-/// Calculate Start and End points of memory access.
-/// Let's assume A is the first access and B is a memory access on N-th loop
-/// iteration. Then B is calculated as:
-///   B = A + Step*N .
-/// Step value may be positive or negative.
-/// N is a calculated back-edge taken count:
-///     N = (TripCount > 0) ? RoundDown(TripCount -1 , VF) : 0
-/// Start and End points are calculated in the following way:
-/// Start = UMIN(A, B) ; End = UMAX(A, B) + SizeOfElt,
-/// where SizeOfElt is the size of single memory access in bytes.
-///
-/// There is no conflict when the intervals are disjoint:
-/// NoConflict = (P2.Start >= P1.End) || (P1.Start >= P2.End)
-void RuntimePointerChecking::insert(Loop *Lp, Value *Ptr, bool WritePtr,
-                                    unsigned DepSetId, unsigned ASId,
-                                    const ValueToValueMap &Strides,
-                                    PredicatedScalarEvolution &PSE) {
-  // Get the stride replaced scev.
-  const SCEV *Sc = replaceSymbolicStrideSCEV(PSE, Strides, Ptr);
-  ScalarEvolution *SE = PSE.getSE();
-
-  const SCEV *ScStart;
-  const SCEV *ScEnd;
-
-  if (SE->isLoopInvariant(Sc, Lp)) {
-    ScStart = ScEnd = Sc;
-  } else {
-    const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Sc);
-    assert(AR && "Invalid addrec expression");
-    const SCEV *Ex = PSE.getBackedgeTakenCount();
-
-    ScStart = AR->getStart();
-    ScEnd = AR->evaluateAtIteration(Ex, *SE);
-    const SCEV *Step = AR->getStepRecurrence(*SE);
-
-    // For expressions with negative step, the upper bound is ScStart and the
-    // lower bound is ScEnd.
-    if (const auto *CStep = dyn_cast<SCEVConstant>(Step)) {
-      if (CStep->getValue()->isNegative())
-        std::swap(ScStart, ScEnd);
-    } else {
-      // Fallback case: the step is not constant, but we can still
-      // get the upper and lower bounds of the interval by using min/max
-      // expressions.
-      ScStart = SE->getUMinExpr(ScStart, ScEnd);
-      ScEnd = SE->getUMaxExpr(AR->getStart(), ScEnd);
-    }
-  }
-  // Add the size of the pointed element to ScEnd.
-  auto &DL = Lp->getHeader()->getModule()->getDataLayout();
-  Type *IdxTy = DL.getIndexType(Ptr->getType());
-  const SCEV *EltSizeSCEV =
-      SE->getStoreSizeOfExpr(IdxTy, Ptr->getType()->getPointerElementType());
-  ScEnd = SE->getAddExpr(ScEnd, EltSizeSCEV);
-
-  Pointers.emplace_back(Ptr, ScStart, ScEnd, WritePtr, DepSetId, ASId, Sc);
-}
-
-SmallVector<RuntimePointerCheck, 4>
-RuntimePointerChecking::generateChecks() const {
-  SmallVector<RuntimePointerCheck, 4> Checks;
-
-  for (unsigned I = 0; I < CheckingGroups.size(); ++I) {
-    for (unsigned J = I + 1; J < CheckingGroups.size(); ++J) {
-      const RuntimeCheckingPtrGroup &CGI = CheckingGroups[I];
-      const RuntimeCheckingPtrGroup &CGJ = CheckingGroups[J];
-
-      if (needsChecking(CGI, CGJ))
-        Checks.push_back(std::make_pair(&CGI, &CGJ));
-    }
-  }
-  return Checks;
-}
-
-void RuntimePointerChecking::generateChecks(
-    MemoryDepChecker::DepCandidates &DepCands, bool UseDependencies) {
-  assert(Checks.empty() && "Checks is not empty");
-  groupChecks(DepCands, UseDependencies);
-  Checks = generateChecks();
-}
-
-bool RuntimePointerChecking::needsChecking(
-    const RuntimeCheckingPtrGroup &M, const RuntimeCheckingPtrGroup &N) const {
-  for (unsigned I = 0, EI = M.Members.size(); EI != I; ++I)
-    for (unsigned J = 0, EJ = N.Members.size(); EJ != J; ++J)
-      if (needsChecking(M.Members[I], N.Members[J]))
-        return true;
-  return false;
-}
-
-/// Compare \p I and \p J and return the minimum.
-/// Return nullptr in case we couldn't find an answer.
-static const SCEV *getMinFromExprs(const SCEV *I, const SCEV *J,
-                                   ScalarEvolution *SE) {
-  const SCEV *Diff = SE->getMinusSCEV(J, I);
-  const SCEVConstant *C = dyn_cast<const SCEVConstant>(Diff);
-
-  if (!C)
-    return nullptr;
-  if (C->getValue()->isNegative())
-    return J;
-  return I;
-}
-
-bool RuntimeCheckingPtrGroup::addPointer(unsigned Index,
-                                         RuntimePointerChecking &RtCheck) {
-  return addPointer(
-      Index, RtCheck.Pointers[Index].Start, RtCheck.Pointers[Index].End,
-      RtCheck.Pointers[Index].PointerValue->getType()->getPointerAddressSpace(),
-      *RtCheck.SE);
-}
-
-bool RuntimeCheckingPtrGroup::addPointer(unsigned Index, const SCEV *Start,
-                                         const SCEV *End, unsigned AS,
-                                         ScalarEvolution &SE) {
-  assert(AddressSpace == AS &&
-         "all pointers in a checking group must be in the same address space");
-
-  // Compare the starts and ends with the known minimum and maximum
-  // of this set. We need to know how we compare against the min/max
-  // of the set in order to be able to emit memchecks.
-  const SCEV *Min0 = getMinFromExprs(Start, Low, &SE);
-  if (!Min0)
-    return false;
-
-  const SCEV *Min1 = getMinFromExprs(End, High, &SE);
-  if (!Min1)
-    return false;
-
-  // Update the low bound  expression if we've found a new min value.
-  if (Min0 == Start)
-    Low = Start;
-
-  // Update the high bound expression if we've found a new max value.
-  if (Min1 != End)
-    High = End;
-
-  Members.push_back(Index);
-  return true;
-}
-
-void RuntimePointerChecking::groupChecks(
-    MemoryDepChecker::DepCandidates &DepCands, bool UseDependencies) {
-  // We build the groups from dependency candidates equivalence classes
-  // because:
-  //    - We know that pointers in the same equivalence class share
-  //      the same underlying object and therefore there is a chance
-  //      that we can compare pointers
-  //    - We wouldn't be able to merge two pointers for which we need
-  //      to emit a memcheck. The classes in DepCands are already
-  //      conveniently built such that no two pointers in the same
-  //      class need checking against each other.
-
-  // We use the following (greedy) algorithm to construct the groups
-  // For every pointer in the equivalence class:
-  //   For each existing group:
-  //   - if the difference between this pointer and the min/max bounds
-  //     of the group is a constant, then make the pointer part of the
-  //     group and update the min/max bounds of that group as required.
-
-  CheckingGroups.clear();
-
-  // If we need to check two pointers to the same underlying object
-  // with a non-constant difference, we shouldn't perform any pointer
-  // grouping with those pointers. This is because we can easily get
-  // into cases where the resulting check would return false, even when
-  // the accesses are safe.
-  //
-  // The following example shows this:
-  // for (i = 0; i < 1000; ++i)
-  //   a[5000 + i * m] = a[i] + a[i + 9000]
-  //
-  // Here grouping gives a check of (5000, 5000 + 1000 * m) against
-  // (0, 10000) which is always false. However, if m is 1, there is no
-  // dependence. Not grouping the checks for a[i] and a[i + 9000] allows
-  // us to perform an accurate check in this case.
-  //
-  // The above case requires that we have an UnknownDependence between
-  // accesses to the same underlying object. This cannot happen unless
-  // FoundNonConstantDistanceDependence is set, and therefore UseDependencies
-  // is also false. In this case we will use the fallback path and create
-  // separate checking groups for all pointers.
-
-  // If we don't have the dependency partitions, construct a new
-  // checking pointer group for each pointer. This is also required
-  // for correctness, because in this case we can have checking between
-  // pointers to the same underlying object.
-  if (!UseDependencies) {
-    for (unsigned I = 0; I < Pointers.size(); ++I)
-      CheckingGroups.push_back(RuntimeCheckingPtrGroup(I, *this));
-    return;
-  }
-
-  unsigned TotalComparisons = 0;
-
-  DenseMap<Value *, unsigned> PositionMap;
-  for (unsigned Index = 0; Index < Pointers.size(); ++Index)
-    PositionMap[Pointers[Index].PointerValue] = Index;
-
-  // We need to keep track of what pointers we've already seen so we
-  // don't process them twice.
-  SmallSet<unsigned, 2> Seen;
-
-  // Go through all equivalence classes, get the "pointer check groups"
-  // and add them to the overall solution. We use the order in which accesses
-  // appear in 'Pointers' to enforce determinism.
-  for (unsigned I = 0; I < Pointers.size(); ++I) {
-    // We've seen this pointer before, and therefore already processed
-    // its equivalence class.
-    if (Seen.count(I))
-      continue;
-
-    MemoryDepChecker::MemAccessInfo Access(Pointers[I].PointerValue,
-                                           Pointers[I].IsWritePtr);
-
-    SmallVector<RuntimeCheckingPtrGroup, 2> Groups;
-    auto LeaderI = DepCands.findValue(DepCands.getLeaderValue(Access));
-
-    // Because DepCands is constructed by visiting accesses in the order in
-    // which they appear in alias sets (which is deterministic) and the
-    // iteration order within an equivalence class member is only dependent on
-    // the order in which unions and insertions are performed on the
-    // equivalence class, the iteration order is deterministic.
-    for (auto MI = DepCands.member_begin(LeaderI), ME = DepCands.member_end();
-         MI != ME; ++MI) {
-      auto PointerI = PositionMap.find(MI->getPointer());
-      assert(PointerI != PositionMap.end() &&
-             "pointer in equivalence class not found in PositionMap");
-      unsigned Pointer = PointerI->second;
-      bool Merged = false;
-      // Mark this pointer as seen.
-      Seen.insert(Pointer);
-
-      // Go through all the existing sets and see if we can find one
-      // which can include this pointer.
-      for (RuntimeCheckingPtrGroup &Group : Groups) {
-        // Don't perform more than a certain amount of comparisons.
-        // This should limit the cost of grouping the pointers to something
-        // reasonable.  If we do end up hitting this threshold, the algorithm
-        // will create separate groups for all remaining pointers.
-        if (TotalComparisons > MemoryCheckMergeThreshold)
-          break;
-
-        TotalComparisons++;
-
-        if (Group.addPointer(Pointer, *this)) {
-          Merged = true;
-          break;
-        }
-      }
-
-      if (!Merged)
-        // We couldn't add this pointer to any existing set or the threshold
-        // for the number of comparisons has been reached. Create a new group
-        // to hold the current pointer.
-        Groups.push_back(RuntimeCheckingPtrGroup(Pointer, *this));
-    }
-
-    // We've computed the grouped checks for this partition.
-    // Save the results and continue with the next one.
-    llvm::copy(Groups, std::back_inserter(CheckingGroups));
-  }
-}
-
-bool RuntimePointerChecking::arePointersInSamePartition(
-    const SmallVectorImpl<int> &PtrToPartition, unsigned PtrIdx1,
-    unsigned PtrIdx2) {
-  return (PtrToPartition[PtrIdx1] != -1 &&
-          PtrToPartition[PtrIdx1] == PtrToPartition[PtrIdx2]);
-}
-
-bool RuntimePointerChecking::needsChecking(unsigned I, unsigned J) const {
-  const PointerInfo &PointerI = Pointers[I];
-  const PointerInfo &PointerJ = Pointers[J];
-
-  // No need to check if two readonly pointers intersect.
-  if (!PointerI.IsWritePtr && !PointerJ.IsWritePtr)
-    return false;
-
-  // Only need to check pointers between two different dependency sets.
-  if (PointerI.DependencySetId == PointerJ.DependencySetId)
-    return false;
-
-  // Only need to check pointers in the same alias set.
-  if (PointerI.AliasSetId != PointerJ.AliasSetId)
-    return false;
-
-  return true;
-}
-
-void RuntimePointerChecking::printChecks(
-    raw_ostream &OS, const SmallVectorImpl<RuntimePointerCheck> &Checks,
-    unsigned Depth) const {
-  unsigned N = 0;
-  for (const auto &Check : Checks) {
-    const auto &First = Check.first->Members, &Second = Check.second->Members;
-
-    OS.indent(Depth) << "Check " << N++ << ":\n";
-
-    OS.indent(Depth + 2) << "Comparing group (" << Check.first << "):\n";
-    for (unsigned K = 0; K < First.size(); ++K)
-      OS.indent(Depth + 2) << *Pointers[First[K]].PointerValue << "\n";
-
-    OS.indent(Depth + 2) << "Against group (" << Check.second << "):\n";
-    for (unsigned K = 0; K < Second.size(); ++K)
-      OS.indent(Depth + 2) << *Pointers[Second[K]].PointerValue << "\n";
-  }
-}
-
-void RuntimePointerChecking::print(raw_ostream &OS, unsigned Depth) const {
-
-  OS.indent(Depth) << "Run-time memory checks:\n";
-  printChecks(OS, Checks, Depth);
-
-  OS.indent(Depth) << "Grouped accesses:\n";
-  for (unsigned I = 0; I < CheckingGroups.size(); ++I) {
-    const auto &CG = CheckingGroups[I];
-
-    OS.indent(Depth + 2) << "Group " << &CG << ":\n";
-    OS.indent(Depth + 4) << "(Low: " << *CG.Low << " High: " << *CG.High
-                         << ")\n";
-    for (unsigned J = 0; J < CG.Members.size(); ++J) {
-      OS.indent(Depth + 6) << "Member: " << *Pointers[CG.Members[J]].Expr
-                           << "\n";
-    }
-  }
-}
-
-namespace {
-
-/// Analyses memory accesses in a loop.
-///
-/// Checks whether run time pointer checks are needed and builds sets for data
-/// dependence checking.
-class AccessAnalysis {
-public:
-  /// Read or write access location.
-  typedef PointerIntPair<Value *, 1, bool> MemAccessInfo;
-  typedef SmallVector<MemAccessInfo, 8> MemAccessInfoList;
-
-  AccessAnalysis(Loop *TheLoop, AAResults *AA, LoopInfo *LI,
-                 MemoryDepChecker::DepCandidates &DA,
-                 PredicatedScalarEvolution &PSE)
-      : TheLoop(TheLoop), AST(*AA), LI(LI), DepCands(DA), PSE(PSE) {}
-
-  /// Register a load  and whether it is only read from.
-  void addLoad(MemoryLocation &Loc, bool IsReadOnly) {
-    Value *Ptr = const_cast<Value*>(Loc.Ptr);
-    AST.add(Ptr, LocationSize::beforeOrAfterPointer(), Loc.AATags);
-    Accesses.insert(MemAccessInfo(Ptr, false));
-    if (IsReadOnly)
-      ReadOnlyPtr.insert(Ptr);
-  }
-
-  /// Register a store.
-  void addStore(MemoryLocation &Loc) {
-    Value *Ptr = const_cast<Value*>(Loc.Ptr);
-    AST.add(Ptr, LocationSize::beforeOrAfterPointer(), Loc.AATags);
-    Accesses.insert(MemAccessInfo(Ptr, true));
-  }
-
-  /// Check if we can emit a run-time no-alias check for \p Access.
-  ///
-  /// Returns true if we can emit a run-time no alias check for \p Access.
-  /// If we can check this access, this also adds it to a dependence set and
-  /// adds a run-time to check for it to \p RtCheck. If \p Assume is true,
-  /// we will attempt to use additional run-time checks in order to get
-  /// the bounds of the pointer.
-  bool createCheckForAccess(RuntimePointerChecking &RtCheck,
-                            MemAccessInfo Access,
-                            const ValueToValueMap &Strides,
-                            DenseMap<Value *, unsigned> &DepSetId,
-                            Loop *TheLoop, unsigned &RunningDepId,
-                            unsigned ASId, bool ShouldCheckStride,
-                            bool Assume);
-
-  /// Check whether we can check the pointers at runtime for
-  /// non-intersection.
-  ///
-  /// Returns true if we need no check or if we do and we can generate them
-  /// (i.e. the pointers have computable bounds).
-  bool canCheckPtrAtRT(RuntimePointerChecking &RtCheck, ScalarEvolution *SE,
-                       Loop *TheLoop, const ValueToValueMap &Strides,
-                       bool ShouldCheckWrap = false);
-
-  /// Goes over all memory accesses, checks whether a RT check is needed
-  /// and builds sets of dependent accesses.
-  void buildDependenceSets() {
-    processMemAccesses();
-  }
-
-  /// Initial processing of memory accesses determined that we need to
-  /// perform dependency checking.
-  ///
-  /// Note that this can later be cleared if we retry memcheck analysis without
-  /// dependency checking (i.e. FoundNonConstantDistanceDependence).
-  bool isDependencyCheckNeeded() { return !CheckDeps.empty(); }
-
-  /// We decided that no dependence analysis would be used.  Reset the state.
-  void resetDepChecks(MemoryDepChecker &DepChecker) {
-    CheckDeps.clear();
-    DepChecker.clearDependences();
-  }
-
-  MemAccessInfoList &getDependenciesToCheck() { return CheckDeps; }
-
-private:
-  typedef SetVector<MemAccessInfo> PtrAccessSet;
-
-  /// Go over all memory access and check whether runtime pointer checks
-  /// are needed and build sets of dependency check candidates.
-  void processMemAccesses();
-
-  /// Set of all accesses.
-  PtrAccessSet Accesses;
-
-  /// The loop being checked.
-  const Loop *TheLoop;
-
-  /// List of accesses that need a further dependence check.
-  MemAccessInfoList CheckDeps;
-
-  /// Set of pointers that are read only.
-  SmallPtrSet<Value*, 16> ReadOnlyPtr;
-
-  /// An alias set tracker to partition the access set by underlying object and
-  //intrinsic property (such as TBAA metadata).
-  AliasSetTracker AST;
-
-  LoopInfo *LI;
-
-  /// Sets of potentially dependent accesses - members of one set share an
-  /// underlying pointer. The set "CheckDeps" identfies which sets really need a
-  /// dependence check.
-  MemoryDepChecker::DepCandidates &DepCands;
-
-  /// Initial processing of memory accesses determined that we may need
-  /// to add memchecks.  Perform the analysis to determine the necessary checks.
-  ///
-  /// Note that, this is different from isDependencyCheckNeeded.  When we retry
-  /// memcheck analysis without dependency checking
-  /// (i.e. FoundNonConstantDistanceDependence), isDependencyCheckNeeded is
-  /// cleared while this remains set if we have potentially dependent accesses.
-  bool IsRTCheckAnalysisNeeded = false;
-
-  /// The SCEV predicate containing all the SCEV-related assumptions.
-  PredicatedScalarEvolution &PSE;
-};
-
-} // end anonymous namespace
-
-/// Check whether a pointer can participate in a runtime bounds check.
-/// If \p Assume, try harder to prove that we can compute the bounds of \p Ptr
-/// by adding run-time checks (overflow checks) if necessary.
-static bool hasComputableBounds(PredicatedScalarEvolution &PSE,
-                                const ValueToValueMap &Strides, Value *Ptr,
-                                Loop *L, bool Assume) {
-  const SCEV *PtrScev = replaceSymbolicStrideSCEV(PSE, Strides, Ptr);
-
-  // The bounds for loop-invariant pointer is trivial.
-  if (PSE.getSE()->isLoopInvariant(PtrScev, L))
-    return true;
-
-  const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(PtrScev);
-
-  if (!AR && Assume)
-    AR = PSE.getAsAddRec(Ptr);
-
-  if (!AR)
-    return false;
-
-  return AR->isAffine();
-}
-
-/// Check whether a pointer address cannot wrap.
-static bool isNoWrap(PredicatedScalarEvolution &PSE,
-                     const ValueToValueMap &Strides, Value *Ptr, Loop *L) {
-  const SCEV *PtrScev = PSE.getSCEV(Ptr);
-  if (PSE.getSE()->isLoopInvariant(PtrScev, L))
-    return true;
-
-  Type *AccessTy = Ptr->getType()->getPointerElementType();
-  int64_t Stride = getPtrStride(PSE, AccessTy, Ptr, L, Strides);
-  if (Stride == 1 || PSE.hasNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW))
-    return true;
-
-  return false;
-}
-
-static void visitPointers(Value *StartPtr, const Loop &InnermostLoop,
-                          function_ref<void(Value *)> AddPointer) {
-  SmallPtrSet<Value *, 8> Visited;
-  SmallVector<Value *> WorkList;
-  WorkList.push_back(StartPtr);
-
-  while (!WorkList.empty()) {
-    Value *Ptr = WorkList.pop_back_val();
-    if (!Visited.insert(Ptr).second)
-      continue;
-    auto *PN = dyn_cast<PHINode>(Ptr);
-    // SCEV does not look through non-header PHIs inside the loop. Such phis
-    // can be analyzed by adding separate accesses for each incoming pointer
-    // value.
-    if (PN && InnermostLoop.contains(PN->getParent()) &&
-        PN->getParent() != InnermostLoop.getHeader()) {
-      for (const Use &Inc : PN->incoming_values())
-        WorkList.push_back(Inc);
-    } else
-      AddPointer(Ptr);
-  }
-}
-
-bool AccessAnalysis::createCheckForAccess(RuntimePointerChecking &RtCheck,
-                                          MemAccessInfo Access,
-                                          const ValueToValueMap &StridesMap,
-                                          DenseMap<Value *, unsigned> &DepSetId,
-                                          Loop *TheLoop, unsigned &RunningDepId,
-                                          unsigned ASId, bool ShouldCheckWrap,
-                                          bool Assume) {
-  Value *Ptr = Access.getPointer();
-
-  if (!hasComputableBounds(PSE, StridesMap, Ptr, TheLoop, Assume))
-    return false;
-
-  // When we run after a failing dependency check we have to make sure
-  // we don't have wrapping pointers.
-  if (ShouldCheckWrap && !isNoWrap(PSE, StridesMap, Ptr, TheLoop)) {
-    auto *Expr = PSE.getSCEV(Ptr);
-    if (!Assume || !isa<SCEVAddRecExpr>(Expr))
-      return false;
-    PSE.setNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW);
-  }
-
-  // The id of the dependence set.
-  unsigned DepId;
-
-  if (isDependencyCheckNeeded()) {
-    Value *Leader = DepCands.getLeaderValue(Access).getPointer();
-    unsigned &LeaderId = DepSetId[Leader];
-    if (!LeaderId)
-      LeaderId = RunningDepId++;
-    DepId = LeaderId;
-  } else
-    // Each access has its own dependence set.
-    DepId = RunningDepId++;
-
-  bool IsWrite = Access.getInt();
-  RtCheck.insert(TheLoop, Ptr, IsWrite, DepId, ASId, StridesMap, PSE);
-  LLVM_DEBUG(dbgs() << "LAA: Found a runtime check ptr:" << *Ptr << '\n');
-
-  return true;
- }
-
-bool AccessAnalysis::canCheckPtrAtRT(RuntimePointerChecking &RtCheck,
-                                     ScalarEvolution *SE, Loop *TheLoop,
-                                     const ValueToValueMap &StridesMap,
-                                     bool ShouldCheckWrap) {
-  // Find pointers with computable bounds. We are going to use this information
-  // to place a runtime bound check.
-  bool CanDoRT = true;
-
-  bool MayNeedRTCheck = false;
-  if (!IsRTCheckAnalysisNeeded) return true;
-
-  bool IsDepCheckNeeded = isDependencyCheckNeeded();
-
-  // We assign a consecutive id to access from different alias sets.
-  // Accesses between different groups doesn't need to be checked.
-  unsigned ASId = 0;
-  for (auto &AS : AST) {
-    int NumReadPtrChecks = 0;
-    int NumWritePtrChecks = 0;
-    bool CanDoAliasSetRT = true;
-    ++ASId;
-
-    // We assign consecutive id to access from different dependence sets.
-    // Accesses within the same set don't need a runtime check.
-    unsigned RunningDepId = 1;
-    DenseMap<Value *, unsigned> DepSetId;
-
-    SmallVector<MemAccessInfo, 4> Retries;
-
-    // First, count how many write and read accesses are in the alias set. Also
-    // collect MemAccessInfos for later.
-    SmallVector<MemAccessInfo, 4> AccessInfos;
-    for (const auto &A : AS) {
-      Value *Ptr = A.getValue();
-      bool IsWrite = Accesses.count(MemAccessInfo(Ptr, true));
-
-      if (IsWrite)
-        ++NumWritePtrChecks;
-      else
-        ++NumReadPtrChecks;
-      AccessInfos.emplace_back(Ptr, IsWrite);
-    }
-
-    // We do not need runtime checks for this alias set, if there are no writes
-    // or a single write and no reads.
-    if (NumWritePtrChecks == 0 ||
-        (NumWritePtrChecks == 1 && NumReadPtrChecks == 0)) {
-      assert((AS.size() <= 1 ||
-              all_of(AS,
-                     [this](auto AC) {
-                       MemAccessInfo AccessWrite(AC.getValue(), true);
-                       return DepCands.findValue(AccessWrite) == DepCands.end();
-                     })) &&
-             "Can only skip updating CanDoRT below, if all entries in AS "
-             "are reads or there is at most 1 entry");
-      continue;
-    }
-
-    for (auto &Access : AccessInfos) {
-      if (!createCheckForAccess(RtCheck, Access, StridesMap, DepSetId, TheLoop,
-                                RunningDepId, ASId, ShouldCheckWrap, false)) {
-        LLVM_DEBUG(dbgs() << "LAA: Can't find bounds for ptr:"
-                          << *Access.getPointer() << '\n');
-        Retries.push_back(Access);
-        CanDoAliasSetRT = false;
-      }
-    }
-
-    // Note that this function computes CanDoRT and MayNeedRTCheck
-    // independently. For example CanDoRT=false, MayNeedRTCheck=false means that
-    // we have a pointer for which we couldn't find the bounds but we don't
-    // actually need to emit any checks so it does not matter.
-    //
-    // We need runtime checks for this alias set, if there are at least 2
-    // dependence sets (in which case RunningDepId > 2) or if we need to re-try
-    // any bound checks (because in that case the number of dependence sets is
-    // incomplete).
-    bool NeedsAliasSetRTCheck = RunningDepId > 2 || !Retries.empty();
-
-    // We need to perform run-time alias checks, but some pointers had bounds
-    // that couldn't be checked.
-    if (NeedsAliasSetRTCheck && !CanDoAliasSetRT) {
-      // Reset the CanDoSetRt flag and retry all accesses that have failed.
-      // We know that we need these checks, so we can now be more aggressive
-      // and add further checks if required (overflow checks).
-      CanDoAliasSetRT = true;
-      for (auto Access : Retries)
-        if (!createCheckForAccess(RtCheck, Access, StridesMap, DepSetId,
-                                  TheLoop, RunningDepId, ASId,
-                                  ShouldCheckWrap, /*Assume=*/true)) {
-          CanDoAliasSetRT = false;
-          break;
-        }
-    }
-
-    CanDoRT &= CanDoAliasSetRT;
-    MayNeedRTCheck |= NeedsAliasSetRTCheck;
-    ++ASId;
-  }
-
-  // If the pointers that we would use for the bounds comparison have different
-  // address spaces, assume the values aren't directly comparable, so we can't
-  // use them for the runtime check. We also have to assume they could
-  // overlap. In the future there should be metadata for whether address spaces
-  // are disjoint.
-  unsigned NumPointers = RtCheck.Pointers.size();
-  for (unsigned i = 0; i < NumPointers; ++i) {
-    for (unsigned j = i + 1; j < NumPointers; ++j) {
-      // Only need to check pointers between two different dependency sets.
-      if (RtCheck.Pointers[i].DependencySetId ==
-          RtCheck.Pointers[j].DependencySetId)
-       continue;
-      // Only need to check pointers in the same alias set.
-      if (RtCheck.Pointers[i].AliasSetId != RtCheck.Pointers[j].AliasSetId)
-        continue;
-
-      Value *PtrI = RtCheck.Pointers[i].PointerValue;
-      Value *PtrJ = RtCheck.Pointers[j].PointerValue;
-
-      unsigned ASi = PtrI->getType()->getPointerAddressSpace();
-      unsigned ASj = PtrJ->getType()->getPointerAddressSpace();
-      if (ASi != ASj) {
-        LLVM_DEBUG(
-            dbgs() << "LAA: Runtime check would require comparison between"
-                      " different address spaces\n");
-        return false;
-      }
-    }
-  }
-
-  if (MayNeedRTCheck && CanDoRT)
-    RtCheck.generateChecks(DepCands, IsDepCheckNeeded);
-
-  LLVM_DEBUG(dbgs() << "LAA: We need to do " << RtCheck.getNumberOfChecks()
-                    << " pointer comparisons.\n");
-
-  // If we can do run-time checks, but there are no checks, no runtime checks
-  // are needed. This can happen when all pointers point to the same underlying
-  // object for example.
-  RtCheck.Need = CanDoRT ? RtCheck.getNumberOfChecks() != 0 : MayNeedRTCheck;
-
-  bool CanDoRTIfNeeded = !RtCheck.Need || CanDoRT;
-  if (!CanDoRTIfNeeded)
-    RtCheck.reset();
-  return CanDoRTIfNeeded;
-}
-
-void AccessAnalysis::processMemAccesses() {
-  // We process the set twice: first we process read-write pointers, last we
-  // process read-only pointers. This allows us to skip dependence tests for
-  // read-only pointers.
-
-  LLVM_DEBUG(dbgs() << "LAA: Processing memory accesses...\n");
-  LLVM_DEBUG(dbgs() << "  AST: "; AST.dump());
-  LLVM_DEBUG(dbgs() << "LAA:   Accesses(" << Accesses.size() << "):\n");
-  LLVM_DEBUG({
-    for (auto A : Accesses)
-      dbgs() << "\t" << *A.getPointer() << " (" <<
-                (A.getInt() ? "write" : (ReadOnlyPtr.count(A.getPointer()) ?
-                                         "read-only" : "read")) << ")\n";
-  });
-
-  // The AliasSetTracker has nicely partitioned our pointers by metadata
-  // compatibility and potential for underlying-object overlap. As a result, we
-  // only need to check for potential pointer dependencies within each alias
-  // set.
-  for (const auto &AS : AST) {
-    // Note that both the alias-set tracker and the alias sets themselves used
-    // linked lists internally and so the iteration order here is deterministic
-    // (matching the original instruction order within each set).
-
-    bool SetHasWrite = false;
-
-    // Map of pointers to last access encountered.
-    typedef DenseMap<const Value*, MemAccessInfo> UnderlyingObjToAccessMap;
-    UnderlyingObjToAccessMap ObjToLastAccess;
-
-    // Set of access to check after all writes have been processed.
-    PtrAccessSet DeferredAccesses;
-
-    // Iterate over each alias set twice, once to process read/write pointers,
-    // and then to process read-only pointers.
-    for (int SetIteration = 0; SetIteration < 2; ++SetIteration) {
-      bool UseDeferred = SetIteration > 0;
-      PtrAccessSet &S = UseDeferred ? DeferredAccesses : Accesses;
-
-      for (const auto &AV : AS) {
-        Value *Ptr = AV.getValue();
-
-        // For a single memory access in AliasSetTracker, Accesses may contain
-        // both read and write, and they both need to be handled for CheckDeps.
-        for (const auto &AC : S) {
-          if (AC.getPointer() != Ptr)
-            continue;
-
-          bool IsWrite = AC.getInt();
-
-          // If we're using the deferred access set, then it contains only
-          // reads.
-          bool IsReadOnlyPtr = ReadOnlyPtr.count(Ptr) && !IsWrite;
-          if (UseDeferred && !IsReadOnlyPtr)
-            continue;
-          // Otherwise, the pointer must be in the PtrAccessSet, either as a
-          // read or a write.
-          assert(((IsReadOnlyPtr && UseDeferred) || IsWrite ||
-                  S.count(MemAccessInfo(Ptr, false))) &&
-                 "Alias-set pointer not in the access set?");
-
-          MemAccessInfo Access(Ptr, IsWrite);
-          DepCands.insert(Access);
-
-          // Memorize read-only pointers for later processing and skip them in
-          // the first round (they need to be checked after we have seen all
-          // write pointers). Note: we also mark pointer that are not
-          // consecutive as "read-only" pointers (so that we check
-          // "a[b[i]] +="). Hence, we need the second check for "!IsWrite".
-          if (!UseDeferred && IsReadOnlyPtr) {
-            DeferredAccesses.insert(Access);
-            continue;
-          }
-
-          // If this is a write - check other reads and writes for conflicts. If
-          // this is a read only check other writes for conflicts (but only if
-          // there is no other write to the ptr - this is an optimization to
-          // catch "a[i] = a[i] + " without having to do a dependence check).
-          if ((IsWrite || IsReadOnlyPtr) && SetHasWrite) {
-            CheckDeps.push_back(Access);
-            IsRTCheckAnalysisNeeded = true;
-          }
-
-          if (IsWrite)
-            SetHasWrite = true;
-
-          // Create sets of pointers connected by a shared alias set and
-          // underlying object.
-          typedef SmallVector<const Value *, 16> ValueVector;
-          ValueVector TempObjects;
-
-          getUnderlyingObjects(Ptr, TempObjects, LI);
-          LLVM_DEBUG(dbgs()
-                     << "Underlying objects for pointer " << *Ptr << "\n");
-          for (const Value *UnderlyingObj : TempObjects) {
-            // nullptr never alias, don't join sets for pointer that have "null"
-            // in their UnderlyingObjects list.
-            if (isa<ConstantPointerNull>(UnderlyingObj) &&
-                !NullPointerIsDefined(
-                    TheLoop->getHeader()->getParent(),
-                    UnderlyingObj->getType()->getPointerAddressSpace()))
-              continue;
-
-            UnderlyingObjToAccessMap::iterator Prev =
-                ObjToLastAccess.find(UnderlyingObj);
-            if (Prev != ObjToLastAccess.end())
-              DepCands.unionSets(Access, Prev->second);
-
-            ObjToLastAccess[UnderlyingObj] = Access;
-            LLVM_DEBUG(dbgs() << "  " << *UnderlyingObj << "\n");
-          }
-        }
-      }
-    }
-  }
-}
-
-static bool isInBoundsGep(Value *Ptr) {
-  if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr))
-    return GEP->isInBounds();
-  return false;
-}
-
-/// Return true if an AddRec pointer \p Ptr is unsigned non-wrapping,
-/// i.e. monotonically increasing/decreasing.
-static bool isNoWrapAddRec(Value *Ptr, const SCEVAddRecExpr *AR,
-                           PredicatedScalarEvolution &PSE, const Loop *L) {
-  // FIXME: This should probably only return true for NUW.
-  if (AR->getNoWrapFlags(SCEV::NoWrapMask))
-    return true;
-
-  // Scalar evolution does not propagate the non-wrapping flags to values that
-  // are derived from a non-wrapping induction variable because non-wrapping
-  // could be flow-sensitive.
-  //
-  // Look through the potentially overflowing instruction to try to prove
-  // non-wrapping for the *specific* value of Ptr.
-
-  // The arithmetic implied by an inbounds GEP can't overflow.
-  auto *GEP = dyn_cast<GetElementPtrInst>(Ptr);
-  if (!GEP || !GEP->isInBounds())
-    return false;
-
-  // Make sure there is only one non-const index and analyze that.
-  Value *NonConstIndex = nullptr;
-  for (Value *Index : GEP->indices())
-    if (!isa<ConstantInt>(Index)) {
-      if (NonConstIndex)
-        return false;
-      NonConstIndex = Index;
-    }
-  if (!NonConstIndex)
-    // The recurrence is on the pointer, ignore for now.
-    return false;
-
-  // The index in GEP is signed.  It is non-wrapping if it's derived from a NSW
-  // AddRec using a NSW operation.
-  if (auto *OBO = dyn_cast<OverflowingBinaryOperator>(NonConstIndex))
-    if (OBO->hasNoSignedWrap() &&
-        // Assume constant for other the operand so that the AddRec can be
-        // easily found.
-        isa<ConstantInt>(OBO->getOperand(1))) {
-      auto *OpScev = PSE.getSCEV(OBO->getOperand(0));
-
-      if (auto *OpAR = dyn_cast<SCEVAddRecExpr>(OpScev))
-        return OpAR->getLoop() == L && OpAR->getNoWrapFlags(SCEV::FlagNSW);
-    }
-
-  return false;
-}
-
-/// Check whether the access through \p Ptr has a constant stride.
-int64_t llvm::getPtrStride(PredicatedScalarEvolution &PSE, Type *AccessTy,
-                           Value *Ptr, const Loop *Lp,
-                           const ValueToValueMap &StridesMap, bool Assume,
-                           bool ShouldCheckWrap) {
-  Type *Ty = Ptr->getType();
-  assert(Ty->isPointerTy() && "Unexpected non-ptr");
-
-  if (isa<ScalableVectorType>(AccessTy)) {
-    LLVM_DEBUG(dbgs() << "LAA: Bad stride - Scalable object: " << *AccessTy
-                      << "\n");
-    return 0;
-  }
-
-  const SCEV *PtrScev = replaceSymbolicStrideSCEV(PSE, StridesMap, Ptr);
-
-  const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(PtrScev);
-  if (Assume && !AR)
-    AR = PSE.getAsAddRec(Ptr);
-
-  if (!AR) {
-    LLVM_DEBUG(dbgs() << "LAA: Bad stride - Not an AddRecExpr pointer " << *Ptr
-                      << " SCEV: " << *PtrScev << "\n");
-    return 0;
-  }
-
-  // The access function must stride over the innermost loop.
-  if (Lp != AR->getLoop()) {
-    LLVM_DEBUG(dbgs() << "LAA: Bad stride - Not striding over innermost loop "
-                      << *Ptr << " SCEV: " << *AR << "\n");
-    return 0;
-  }
-
-  // The address calculation must not wrap. Otherwise, a dependence could be
-  // inverted.
-  // An inbounds getelementptr that is a AddRec with a unit stride
-  // cannot wrap per definition. The unit stride requirement is checked later.
-  // An getelementptr without an inbounds attribute and unit stride would have
-  // to access the pointer value "0" which is undefined behavior in address
-  // space 0, therefore we can also vectorize this case.
-  unsigned AddrSpace = Ty->getPointerAddressSpace();
-  bool IsInBoundsGEP = isInBoundsGep(Ptr);
-  bool IsNoWrapAddRec = !ShouldCheckWrap ||
-    PSE.hasNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW) ||
-    isNoWrapAddRec(Ptr, AR, PSE, Lp);
-  if (!IsNoWrapAddRec && !IsInBoundsGEP &&
-      NullPointerIsDefined(Lp->getHeader()->getParent(), AddrSpace)) {
-    if (Assume) {
-      PSE.setNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW);
-      IsNoWrapAddRec = true;
-      LLVM_DEBUG(dbgs() << "LAA: Pointer may wrap in the address space:\n"
-                        << "LAA:   Pointer: " << *Ptr << "\n"
-                        << "LAA:   SCEV: " << *AR << "\n"
-                        << "LAA:   Added an overflow assumption\n");
-    } else {
-      LLVM_DEBUG(
-          dbgs() << "LAA: Bad stride - Pointer may wrap in the address space "
-                 << *Ptr << " SCEV: " << *AR << "\n");
-      return 0;
-    }
-  }
-
-  // Check the step is constant.
-  const SCEV *Step = AR->getStepRecurrence(*PSE.getSE());
-
-  // Calculate the pointer stride and check if it is constant.
-  const SCEVConstant *C = dyn_cast<SCEVConstant>(Step);
-  if (!C) {
-    LLVM_DEBUG(dbgs() << "LAA: Bad stride - Not a constant strided " << *Ptr
-                      << " SCEV: " << *AR << "\n");
-    return 0;
-  }
-
-  auto &DL = Lp->getHeader()->getModule()->getDataLayout();
-  TypeSize AllocSize = DL.getTypeAllocSize(AccessTy);
-  int64_t Size = AllocSize.getFixedSize();
-  const APInt &APStepVal = C->getAPInt();
-
-  // Huge step value - give up.
-  if (APStepVal.getBitWidth() > 64)
-    return 0;
-
-  int64_t StepVal = APStepVal.getSExtValue();
-
-  // Strided access.
-  int64_t Stride = StepVal / Size;
-  int64_t Rem = StepVal % Size;
-  if (Rem)
-    return 0;
-
-  // If the SCEV could wrap but we have an inbounds gep with a unit stride we
-  // know we can't "wrap around the address space". In case of address space
-  // zero we know that this won't happen without triggering undefined behavior.
-  if (!IsNoWrapAddRec && Stride != 1 && Stride != -1 &&
-      (IsInBoundsGEP || !NullPointerIsDefined(Lp->getHeader()->getParent(),
-                                              AddrSpace))) {
-    if (Assume) {
-      // We can avoid this case by adding a run-time check.
-      LLVM_DEBUG(dbgs() << "LAA: Non unit strided pointer which is not either "
-                        << "inbounds or in address space 0 may wrap:\n"
-                        << "LAA:   Pointer: " << *Ptr << "\n"
-                        << "LAA:   SCEV: " << *AR << "\n"
-                        << "LAA:   Added an overflow assumption\n");
-      PSE.setNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW);
-    } else
-      return 0;
-  }
-
-  return Stride;
-}
-
-Optional<int> llvm::getPointersDiff(Type *ElemTyA, Value *PtrA, Type *ElemTyB,
-                                    Value *PtrB, const DataLayout &DL,
-                                    ScalarEvolution &SE, bool StrictCheck,
-                                    bool CheckType) {
-  assert(PtrA && PtrB && "Expected non-nullptr pointers.");
-  assert(cast<PointerType>(PtrA->getType())
-             ->isOpaqueOrPointeeTypeMatches(ElemTyA) && "Wrong PtrA type");
-  assert(cast<PointerType>(PtrB->getType())
-             ->isOpaqueOrPointeeTypeMatches(ElemTyB) && "Wrong PtrB type");
-
-  // Make sure that A and B are different pointers.
-  if (PtrA == PtrB)
-    return 0;
-
-  // Make sure that the element types are the same if required.
-  if (CheckType && ElemTyA != ElemTyB)
-    return None;
-
-  unsigned ASA = PtrA->getType()->getPointerAddressSpace();
-  unsigned ASB = PtrB->getType()->getPointerAddressSpace();
-
-  // Check that the address spaces match.
-  if (ASA != ASB)
-    return None;
-  unsigned IdxWidth = DL.getIndexSizeInBits(ASA);
-
-  APInt OffsetA(IdxWidth, 0), OffsetB(IdxWidth, 0);
-  Value *PtrA1 = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA);
-  Value *PtrB1 = PtrB->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetB);
-
-  int Val;
-  if (PtrA1 == PtrB1) {
-    // Retrieve the address space again as pointer stripping now tracks through
-    // `addrspacecast`.
-    ASA = cast<PointerType>(PtrA1->getType())->getAddressSpace();
-    ASB = cast<PointerType>(PtrB1->getType())->getAddressSpace();
-    // Check that the address spaces match and that the pointers are valid.
-    if (ASA != ASB)
-      return None;
-
-    IdxWidth = DL.getIndexSizeInBits(ASA);
-    OffsetA = OffsetA.sextOrTrunc(IdxWidth);
-    OffsetB = OffsetB.sextOrTrunc(IdxWidth);
-
-    OffsetB -= OffsetA;
-    Val = OffsetB.getSExtValue();
-  } else {
-    // Otherwise compute the distance with SCEV between the base pointers.
-    const SCEV *PtrSCEVA = SE.getSCEV(PtrA);
-    const SCEV *PtrSCEVB = SE.getSCEV(PtrB);
-    const auto *Diff =
-        dyn_cast<SCEVConstant>(SE.getMinusSCEV(PtrSCEVB, PtrSCEVA));
-    if (!Diff)
-      return None;
-    Val = Diff->getAPInt().getSExtValue();
-  }
-  int Size = DL.getTypeStoreSize(ElemTyA);
-  int Dist = Val / Size;
-
-  // Ensure that the calculated distance matches the type-based one after all
-  // the bitcasts removal in the provided pointers.
-  if (!StrictCheck || Dist * Size == Val)
-    return Dist;
-  return None;
-}
-
-bool llvm::sortPtrAccesses(ArrayRef<Value *> VL, Type *ElemTy,
-                           const DataLayout &DL, ScalarEvolution &SE,
-                           SmallVectorImpl<unsigned> &SortedIndices) {
-  assert(llvm::all_of(
-             VL, [](const Value *V) { return V->getType()->isPointerTy(); }) &&
-         "Expected list of pointer operands.");
-  // Walk over the pointers, and map each of them to an offset relative to
-  // first pointer in the array.
-  Value *Ptr0 = VL[0];
-
-  using DistOrdPair = std::pair<int64_t, int>;
-  auto Compare = [](const DistOrdPair &L, const DistOrdPair &R) {
-    return L.first < R.first;
-  };
-  std::set<DistOrdPair, decltype(Compare)> Offsets(Compare);
-  Offsets.emplace(0, 0);
-  int Cnt = 1;
-  bool IsConsecutive = true;
-  for (auto *Ptr : VL.drop_front()) {
-    Optional<int> Diff = getPointersDiff(ElemTy, Ptr0, ElemTy, Ptr, DL, SE,
-                                         /*StrictCheck=*/true);
-    if (!Diff)
-      return false;
-
-    // Check if the pointer with the same offset is found.
-    int64_t Offset = *Diff;
-    auto Res = Offsets.emplace(Offset, Cnt);
-    if (!Res.second)
-      return false;
-    // Consecutive order if the inserted element is the last one.
-    IsConsecutive = IsConsecutive && std::next(Res.first) == Offsets.end();
-    ++Cnt;
-  }
-  SortedIndices.clear();
-  if (!IsConsecutive) {
-    // Fill SortedIndices array only if it is non-consecutive.
-    SortedIndices.resize(VL.size());
-    Cnt = 0;
-    for (const std::pair<int64_t, int> &Pair : Offsets) {
-      SortedIndices[Cnt] = Pair.second;
-      ++Cnt;
-    }
-  }
-  return true;
-}
-
-/// Returns true if the memory operations \p A and \p B are consecutive.
-bool llvm::isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL,
-                               ScalarEvolution &SE, bool CheckType) {
-  Value *PtrA = getLoadStorePointerOperand(A);
-  Value *PtrB = getLoadStorePointerOperand(B);
-  if (!PtrA || !PtrB)
-    return false;
-  Type *ElemTyA = getLoadStoreType(A);
-  Type *ElemTyB = getLoadStoreType(B);
-  Optional<int> Diff = getPointersDiff(ElemTyA, PtrA, ElemTyB, PtrB, DL, SE,
-                                       /*StrictCheck=*/true, CheckType);
-  return Diff && *Diff == 1;
-}
-
-void MemoryDepChecker::addAccess(StoreInst *SI) {
-  visitPointers(SI->getPointerOperand(), *InnermostLoop,
-                [this, SI](Value *Ptr) {
-                  Accesses[MemAccessInfo(Ptr, true)].push_back(AccessIdx);
-                  InstMap.push_back(SI);
-                  ++AccessIdx;
-                });
-}
-
-void MemoryDepChecker::addAccess(LoadInst *LI) {
-  visitPointers(LI->getPointerOperand(), *InnermostLoop,
-                [this, LI](Value *Ptr) {
-                  Accesses[MemAccessInfo(Ptr, false)].push_back(AccessIdx);
-                  InstMap.push_back(LI);
-                  ++AccessIdx;
-                });
-}
-
-MemoryDepChecker::VectorizationSafetyStatus
-MemoryDepChecker::Dependence::isSafeForVectorization(DepType Type) {
-  switch (Type) {
-  case NoDep:
-  case Forward:
-  case BackwardVectorizable:
-    return VectorizationSafetyStatus::Safe;
-
-  case Unknown:
-    return VectorizationSafetyStatus::PossiblySafeWithRtChecks;
-  case ForwardButPreventsForwarding:
-  case Backward:
-  case BackwardVectorizableButPreventsForwarding:
-    return VectorizationSafetyStatus::Unsafe;
-  }
-  llvm_unreachable("unexpected DepType!");
-}
-
-bool MemoryDepChecker::Dependence::isBackward() const {
-  switch (Type) {
-  case NoDep:
-  case Forward:
-  case ForwardButPreventsForwarding:
-  case Unknown:
-    return false;
-
-  case BackwardVectorizable:
-  case Backward:
-  case BackwardVectorizableButPreventsForwarding:
-    return true;
-  }
-  llvm_unreachable("unexpected DepType!");
-}
-
-bool MemoryDepChecker::Dependence::isPossiblyBackward() const {
-  return isBackward() || Type == Unknown;
-}
-
-bool MemoryDepChecker::Dependence::isForward() const {
-  switch (Type) {
-  case Forward:
-  case ForwardButPreventsForwarding:
-    return true;
-
-  case NoDep:
-  case Unknown:
-  case BackwardVectorizable:
-  case Backward:
-  case BackwardVectorizableButPreventsForwarding:
-    return false;
-  }
-  llvm_unreachable("unexpected DepType!");
-}
-
-bool MemoryDepChecker::couldPreventStoreLoadForward(uint64_t Distance,
-                                                    uint64_t TypeByteSize) {
-  // If loads occur at a distance that is not a multiple of a feasible vector
-  // factor store-load forwarding does not take place.
-  // Positive dependences might cause troubles because vectorizing them might
-  // prevent store-load forwarding making vectorized code run a lot slower.
-  //   a[i] = a[i-3] ^ a[i-8];
-  //   The stores to a[i:i+1] don't align with the stores to a[i-3:i-2] and
-  //   hence on your typical architecture store-load forwarding does not take
-  //   place. Vectorizing in such cases does not make sense.
-  // Store-load forwarding distance.
-
-  // After this many iterations store-to-load forwarding conflicts should not
-  // cause any slowdowns.
-  const uint64_t NumItersForStoreLoadThroughMemory = 8 * TypeByteSize;
-  // Maximum vector factor.
-  uint64_t MaxVFWithoutSLForwardIssues = std::min(
-      VectorizerParams::MaxVectorWidth * TypeByteSize, MaxSafeDepDistBytes);
-
-  // Compute the smallest VF at which the store and load would be misaligned.
-  for (uint64_t VF = 2 * TypeByteSize; VF <= MaxVFWithoutSLForwardIssues;
-       VF *= 2) {
-    // If the number of vector iteration between the store and the load are
-    // small we could incur conflicts.
-    if (Distance % VF && Distance / VF < NumItersForStoreLoadThroughMemory) {
-      MaxVFWithoutSLForwardIssues = (VF >> 1);
-      break;
-    }
-  }
-
-  if (MaxVFWithoutSLForwardIssues < 2 * TypeByteSize) {
-    LLVM_DEBUG(
-        dbgs() << "LAA: Distance " << Distance
-               << " that could cause a store-load forwarding conflict\n");
-    return true;
-  }
-
-  if (MaxVFWithoutSLForwardIssues < MaxSafeDepDistBytes &&
-      MaxVFWithoutSLForwardIssues !=
-          VectorizerParams::MaxVectorWidth * TypeByteSize)
-    MaxSafeDepDistBytes = MaxVFWithoutSLForwardIssues;
-  return false;
-}
-
-void MemoryDepChecker::mergeInStatus(VectorizationSafetyStatus S) {
-  if (Status < S)
-    Status = S;
-}
-
-/// Given a non-constant (unknown) dependence-distance \p Dist between two
-/// memory accesses, that have the same stride whose absolute value is given
-/// in \p Stride, and that have the same type size \p TypeByteSize,
-/// in a loop whose takenCount is \p BackedgeTakenCount, check if it is
-/// possible to prove statically that the dependence distance is larger
-/// than the range that the accesses will travel through the execution of
-/// the loop. If so, return true; false otherwise. This is useful for
-/// example in loops such as the following (PR31098):
-///     for (i = 0; i < D; ++i) {
-///                = out[i];
-///       out[i+D] =
-///     }
-static bool isSafeDependenceDistance(const DataLayout &DL, ScalarEvolution &SE,
-                                     const SCEV &BackedgeTakenCount,
-                                     const SCEV &Dist, uint64_t Stride,
-                                     uint64_t TypeByteSize) {
-
-  // If we can prove that
-  //      (**) |Dist| > BackedgeTakenCount * Step
-  // where Step is the absolute stride of the memory accesses in bytes,
-  // then there is no dependence.
-  //
-  // Rationale:
-  // We basically want to check if the absolute distance (|Dist/Step|)
-  // is >= the loop iteration count (or > BackedgeTakenCount).
-  // This is equivalent to the Strong SIV Test (Practical Dependence Testing,
-  // Section 4.2.1); Note, that for vectorization it is sufficient to prove
-  // that the dependence distance is >= VF; This is checked elsewhere.
-  // But in some cases we can prune unknown dependence distances early, and
-  // even before selecting the VF, and without a runtime test, by comparing
-  // the distance against the loop iteration count. Since the vectorized code
-  // will be executed only if LoopCount >= VF, proving distance >= LoopCount
-  // also guarantees that distance >= VF.
-  //
-  const uint64_t ByteStride = Stride * TypeByteSize;
-  const SCEV *Step = SE.getConstant(BackedgeTakenCount.getType(), ByteStride);
-  const SCEV *Product = SE.getMulExpr(&BackedgeTakenCount, Step);
-
-  const SCEV *CastedDist = &Dist;
-  const SCEV *CastedProduct = Product;
-  uint64_t DistTypeSize = DL.getTypeAllocSize(Dist.getType());
-  uint64_t ProductTypeSize = DL.getTypeAllocSize(Product->getType());
-
-  // The dependence distance can be positive/negative, so we sign extend Dist;
-  // The multiplication of the absolute stride in bytes and the
-  // backedgeTakenCount is non-negative, so we zero extend Product.
-  if (DistTypeSize > ProductTypeSize)
-    CastedProduct = SE.getZeroExtendExpr(Product, Dist.getType());
-  else
-    CastedDist = SE.getNoopOrSignExtend(&Dist, Product->getType());
-
-  // Is  Dist - (BackedgeTakenCount * Step) > 0 ?
-  // (If so, then we have proven (**) because |Dist| >= Dist)
-  const SCEV *Minus = SE.getMinusSCEV(CastedDist, CastedProduct);
-  if (SE.isKnownPositive(Minus))
-    return true;
-
-  // Second try: Is  -Dist - (BackedgeTakenCount * Step) > 0 ?
-  // (If so, then we have proven (**) because |Dist| >= -1*Dist)
-  const SCEV *NegDist = SE.getNegativeSCEV(CastedDist);
-  Minus = SE.getMinusSCEV(NegDist, CastedProduct);
-  if (SE.isKnownPositive(Minus))
-    return true;
-
-  return false;
-}
-
-/// Check the dependence for two accesses with the same stride \p Stride.
-/// \p Distance is the positive distance and \p TypeByteSize is type size in
-/// bytes.
-///
-/// \returns true if they are independent.
-static bool areStridedAccessesIndependent(uint64_t Distance, uint64_t Stride,
-                                          uint64_t TypeByteSize) {
-  assert(Stride > 1 && "The stride must be greater than 1");
-  assert(TypeByteSize > 0 && "The type size in byte must be non-zero");
-  assert(Distance > 0 && "The distance must be non-zero");
-
-  // Skip if the distance is not multiple of type byte size.
-  if (Distance % TypeByteSize)
-    return false;
-
-  uint64_t ScaledDist = Distance / TypeByteSize;
-
-  // No dependence if the scaled distance is not multiple of the stride.
-  // E.g.
-  //      for (i = 0; i < 1024 ; i += 4)
-  //        A[i+2] = A[i] + 1;
-  //
-  // Two accesses in memory (scaled distance is 2, stride is 4):
-  //     | A[0] |      |      |      | A[4] |      |      |      |
-  //     |      |      | A[2] |      |      |      | A[6] |      |
-  //
-  // E.g.
-  //      for (i = 0; i < 1024 ; i += 3)
-  //        A[i+4] = A[i] + 1;
-  //
-  // Two accesses in memory (scaled distance is 4, stride is 3):
-  //     | A[0] |      |      | A[3] |      |      | A[6] |      |      |
-  //     |      |      |      |      | A[4] |      |      | A[7] |      |
-  return ScaledDist % Stride;
-}
-
-MemoryDepChecker::Dependence::DepType
-MemoryDepChecker::isDependent(const MemAccessInfo &A, unsigned AIdx,
-                              const MemAccessInfo &B, unsigned BIdx,
-                              const ValueToValueMap &Strides) {
-  assert (AIdx < BIdx && "Must pass arguments in program order");
-
-  Value *APtr = A.getPointer();
-  Value *BPtr = B.getPointer();
-  bool AIsWrite = A.getInt();
-  bool BIsWrite = B.getInt();
-  Type *ATy = APtr->getType()->getPointerElementType();
-  Type *BTy = BPtr->getType()->getPointerElementType();
-
-  // Two reads are independent.
-  if (!AIsWrite && !BIsWrite)
-    return Dependence::NoDep;
-
-  // We cannot check pointers in different address spaces.
-  if (APtr->getType()->getPointerAddressSpace() !=
-      BPtr->getType()->getPointerAddressSpace())
-    return Dependence::Unknown;
-
-  int64_t StrideAPtr =
-      getPtrStride(PSE, ATy, APtr, InnermostLoop, Strides, true);
-  int64_t StrideBPtr =
-      getPtrStride(PSE, BTy, BPtr, InnermostLoop, Strides, true);
-
-  const SCEV *Src = PSE.getSCEV(APtr);
-  const SCEV *Sink = PSE.getSCEV(BPtr);
-
-  // If the induction step is negative we have to invert source and sink of the
-  // dependence.
-  if (StrideAPtr < 0) {
-    std::swap(APtr, BPtr);
-    std::swap(ATy, BTy);
-    std::swap(Src, Sink);
-    std::swap(AIsWrite, BIsWrite);
-    std::swap(AIdx, BIdx);
-    std::swap(StrideAPtr, StrideBPtr);
-  }
-
-  const SCEV *Dist = PSE.getSE()->getMinusSCEV(Sink, Src);
-
-  LLVM_DEBUG(dbgs() << "LAA: Src Scev: " << *Src << "Sink Scev: " << *Sink
-                    << "(Induction step: " << StrideAPtr << ")\n");
-  LLVM_DEBUG(dbgs() << "LAA: Distance for " << *InstMap[AIdx] << " to "
-                    << *InstMap[BIdx] << ": " << *Dist << "\n");
-
-  // Need accesses with constant stride. We don't want to vectorize
-  // "A[B[i]] += ..." and similar code or pointer arithmetic that could wrap in
-  // the address space.
-  if (!StrideAPtr || !StrideBPtr || StrideAPtr != StrideBPtr){
-    LLVM_DEBUG(dbgs() << "Pointer access with non-constant stride\n");
-    return Dependence::Unknown;
-  }
-
-  auto &DL = InnermostLoop->getHeader()->getModule()->getDataLayout();
-  uint64_t TypeByteSize = DL.getTypeAllocSize(ATy);
-  bool HasSameSize =
-      DL.getTypeStoreSizeInBits(ATy) == DL.getTypeStoreSizeInBits(BTy);
-  uint64_t Stride = std::abs(StrideAPtr);
-  const SCEVConstant *C = dyn_cast<SCEVConstant>(Dist);
-  if (!C) {
-    if (!isa<SCEVCouldNotCompute>(Dist) && HasSameSize &&
-        isSafeDependenceDistance(DL, *(PSE.getSE()),
-                                 *(PSE.getBackedgeTakenCount()), *Dist, Stride,
-                                 TypeByteSize))
-      return Dependence::NoDep;
-
-    LLVM_DEBUG(dbgs() << "LAA: Dependence because of non-constant distance\n");
-    FoundNonConstantDistanceDependence = true;
-    return Dependence::Unknown;
-  }
-
-  const APInt &Val = C->getAPInt();
-  int64_t Distance = Val.getSExtValue();
-
-  // Attempt to prove strided accesses independent.
-  if (std::abs(Distance) > 0 && Stride > 1 && HasSameSize &&
-      areStridedAccessesIndependent(std::abs(Distance), Stride, TypeByteSize)) {
-    LLVM_DEBUG(dbgs() << "LAA: Strided accesses are independent\n");
-    return Dependence::NoDep;
-  }
-
-  // Negative distances are not plausible dependencies.
-  if (Val.isNegative()) {
-    bool IsTrueDataDependence = (AIsWrite && !BIsWrite);
-    if (IsTrueDataDependence && EnableForwardingConflictDetection &&
-        (couldPreventStoreLoadForward(Val.abs().getZExtValue(), TypeByteSize) ||
-         !HasSameSize)) {
-      LLVM_DEBUG(dbgs() << "LAA: Forward but may prevent st->ld forwarding\n");
-      return Dependence::ForwardButPreventsForwarding;
-    }
-
-    LLVM_DEBUG(dbgs() << "LAA: Dependence is negative\n");
-    return Dependence::Forward;
-  }
-
-  // Write to the same location with the same size.
-  if (Val == 0) {
-    if (HasSameSize)
-      return Dependence::Forward;
-    LLVM_DEBUG(
-        dbgs() << "LAA: Zero dependence difference but different type sizes\n");
-    return Dependence::Unknown;
-  }
-
-  assert(Val.isStrictlyPositive() && "Expect a positive value");
-
-  if (!HasSameSize) {
-    LLVM_DEBUG(dbgs() << "LAA: ReadWrite-Write positive dependency with "
-                         "different type sizes\n");
-    return Dependence::Unknown;
-  }
-
-  // Bail out early if passed-in parameters make vectorization not feasible.
-  unsigned ForcedFactor = (VectorizerParams::VectorizationFactor ?
-                           VectorizerParams::VectorizationFactor : 1);
-  unsigned ForcedUnroll = (VectorizerParams::VectorizationInterleave ?
-                           VectorizerParams::VectorizationInterleave : 1);
-  // The minimum number of iterations for a vectorized/unrolled version.
-  unsigned MinNumIter = std::max(ForcedFactor * ForcedUnroll, 2U);
-
-  // It's not vectorizable if the distance is smaller than the minimum distance
-  // needed for a vectroized/unrolled version. Vectorizing one iteration in
-  // front needs TypeByteSize * Stride. Vectorizing the last iteration needs
-  // TypeByteSize (No need to plus the last gap distance).
-  //
-  // E.g. Assume one char is 1 byte in memory and one int is 4 bytes.
-  //      foo(int *A) {
-  //        int *B = (int *)((char *)A + 14);
-  //        for (i = 0 ; i < 1024 ; i += 2)
-  //          B[i] = A[i] + 1;
-  //      }
-  //
-  // Two accesses in memory (stride is 2):
-  //     | A[0] |      | A[2] |      | A[4] |      | A[6] |      |
-  //                              | B[0] |      | B[2] |      | B[4] |
-  //
-  // Distance needs for vectorizing iterations except the last iteration:
-  // 4 * 2 * (MinNumIter - 1). Distance needs for the last iteration: 4.
-  // So the minimum distance needed is: 4 * 2 * (MinNumIter - 1) + 4.
-  //
-  // If MinNumIter is 2, it is vectorizable as the minimum distance needed is
-  // 12, which is less than distance.
-  //
-  // If MinNumIter is 4 (Say if a user forces the vectorization factor to be 4),
-  // the minimum distance needed is 28, which is greater than distance. It is
-  // not safe to do vectorization.
-  uint64_t MinDistanceNeeded =
-      TypeByteSize * Stride * (MinNumIter - 1) + TypeByteSize;
-  if (MinDistanceNeeded > static_cast<uint64_t>(Distance)) {
-    LLVM_DEBUG(dbgs() << "LAA: Failure because of positive distance "
-                      << Distance << '\n');
-    return Dependence::Backward;
-  }
-
-  // Unsafe if the minimum distance needed is greater than max safe distance.
-  if (MinDistanceNeeded > MaxSafeDepDistBytes) {
-    LLVM_DEBUG(dbgs() << "LAA: Failure because it needs at least "
-                      << MinDistanceNeeded << " size in bytes");
-    return Dependence::Backward;
-  }
-
-  // Positive distance bigger than max vectorization factor.
-  // FIXME: Should use max factor instead of max distance in bytes, which could
-  // not handle different types.
-  // E.g. Assume one char is 1 byte in memory and one int is 4 bytes.
-  //      void foo (int *A, char *B) {
-  //        for (unsigned i = 0; i < 1024; i++) {
-  //          A[i+2] = A[i] + 1;
-  //          B[i+2] = B[i] + 1;
-  //        }
-  //      }
-  //
-  // This case is currently unsafe according to the max safe distance. If we
-  // analyze the two accesses on array B, the max safe dependence distance
-  // is 2. Then we analyze the accesses on array A, the minimum distance needed
-  // is 8, which is less than 2 and forbidden vectorization, But actually
-  // both A and B could be vectorized by 2 iterations.
-  MaxSafeDepDistBytes =
-      std::min(static_cast<uint64_t>(Distance), MaxSafeDepDistBytes);
-
-  bool IsTrueDataDependence = (!AIsWrite && BIsWrite);
-  if (IsTrueDataDependence && EnableForwardingConflictDetection &&
-      couldPreventStoreLoadForward(Distance, TypeByteSize))
-    return Dependence::BackwardVectorizableButPreventsForwarding;
-
-  uint64_t MaxVF = MaxSafeDepDistBytes / (TypeByteSize * Stride);
-  LLVM_DEBUG(dbgs() << "LAA: Positive distance " << Val.getSExtValue()
-                    << " with max VF = " << MaxVF << '\n');
-  uint64_t MaxVFInBits = MaxVF * TypeByteSize * 8;
-  MaxSafeVectorWidthInBits = std::min(MaxSafeVectorWidthInBits, MaxVFInBits);
-  return Dependence::BackwardVectorizable;
-}
-
-bool MemoryDepChecker::areDepsSafe(DepCandidates &AccessSets,
-                                   MemAccessInfoList &CheckDeps,
-                                   const ValueToValueMap &Strides) {
-
-  MaxSafeDepDistBytes = -1;
-  SmallPtrSet<MemAccessInfo, 8> Visited;
-  for (MemAccessInfo CurAccess : CheckDeps) {
-    if (Visited.count(CurAccess))
-      continue;
-
-    // Get the relevant memory access set.
-    EquivalenceClasses<MemAccessInfo>::iterator I =
-      AccessSets.findValue(AccessSets.getLeaderValue(CurAccess));
-
-    // Check accesses within this set.
-    EquivalenceClasses<MemAccessInfo>::member_iterator AI =
-        AccessSets.member_begin(I);
-    EquivalenceClasses<MemAccessInfo>::member_iterator AE =
-        AccessSets.member_end();
-
-    // Check every access pair.
-    while (AI != AE) {
-      Visited.insert(*AI);
-      bool AIIsWrite = AI->getInt();
-      // Check loads only against next equivalent class, but stores also against
-      // other stores in the same equivalence class - to the same address.
-      EquivalenceClasses<MemAccessInfo>::member_iterator OI =
-          (AIIsWrite ? AI : std::next(AI));
-      while (OI != AE) {
-        // Check every accessing instruction pair in program order.
-        for (std::vector<unsigned>::iterator I1 = Accesses[*AI].begin(),
-             I1E = Accesses[*AI].end(); I1 != I1E; ++I1)
-          // Scan all accesses of another equivalence class, but only the next
-          // accesses of the same equivalent class.
-          for (std::vector<unsigned>::iterator
-                   I2 = (OI == AI ? std::next(I1) : Accesses[*OI].begin()),
-                   I2E = (OI == AI ? I1E : Accesses[*OI].end());
-               I2 != I2E; ++I2) {
-            auto A = std::make_pair(&*AI, *I1);
-            auto B = std::make_pair(&*OI, *I2);
-
-            assert(*I1 != *I2);
-            if (*I1 > *I2)
-              std::swap(A, B);
-
-            Dependence::DepType Type =
-                isDependent(*A.first, A.second, *B.first, B.second, Strides);
-            mergeInStatus(Dependence::isSafeForVectorization(Type));
-
-            // Gather dependences unless we accumulated MaxDependences
-            // dependences.  In that case return as soon as we find the first
-            // unsafe dependence.  This puts a limit on this quadratic
-            // algorithm.
-            if (RecordDependences) {
-              if (Type != Dependence::NoDep)
-                Dependences.push_back(Dependence(A.second, B.second, Type));
-
-              if (Dependences.size() >= MaxDependences) {
-                RecordDependences = false;
-                Dependences.clear();
-                LLVM_DEBUG(dbgs()
-                           << "Too many dependences, stopped recording\n");
-              }
-            }
-            if (!RecordDependences && !isSafeForVectorization())
-              return false;
-          }
-        ++OI;
-      }
-      AI++;
-    }
-  }
-
-  LLVM_DEBUG(dbgs() << "Total Dependences: " << Dependences.size() << "\n");
-  return isSafeForVectorization();
-}
-
-SmallVector<Instruction *, 4>
-MemoryDepChecker::getInstructionsForAccess(Value *Ptr, bool isWrite) const {
-  MemAccessInfo Access(Ptr, isWrite);
-  auto &IndexVector = Accesses.find(Access)->second;
-
-  SmallVector<Instruction *, 4> Insts;
-  transform(IndexVector,
-                 std::back_inserter(Insts),
-                 [&](unsigned Idx) { return this->InstMap[Idx]; });
-  return Insts;
-}
-
-const char *MemoryDepChecker::Dependence::DepName[] = {
-    "NoDep", "Unknown", "Forward", "ForwardButPreventsForwarding", "Backward",
-    "BackwardVectorizable", "BackwardVectorizableButPreventsForwarding"};
-
-void MemoryDepChecker::Dependence::print(
-    raw_ostream &OS, unsigned Depth,
-    const SmallVectorImpl<Instruction *> &Instrs) const {
-  OS.indent(Depth) << DepName[Type] << ":\n";
-  OS.indent(Depth + 2) << *Instrs[Source] << " -> \n";
-  OS.indent(Depth + 2) << *Instrs[Destination] << "\n";
-}
-
-bool LoopAccessInfo::canAnalyzeLoop() {
-  // We need to have a loop header.
-  LLVM_DEBUG(dbgs() << "LAA: Found a loop in "
-                    << TheLoop->getHeader()->getParent()->getName() << ": "
-                    << TheLoop->getHeader()->getName() << '\n');
-
-  // We can only analyze innermost loops.
-  if (!TheLoop->isInnermost()) {
-    LLVM_DEBUG(dbgs() << "LAA: loop is not the innermost loop\n");
-    recordAnalysis("NotInnerMostLoop") << "loop is not the innermost loop";
-    return false;
-  }
-
-  // We must have a single backedge.
-  if (TheLoop->getNumBackEdges() != 1) {
-    LLVM_DEBUG(
-        dbgs() << "LAA: loop control flow is not understood by analyzer\n");
-    recordAnalysis("CFGNotUnderstood")
-        << "loop control flow is not understood by analyzer";
-    return false;
-  }
-
-  // ScalarEvolution needs to be able to find the exit count.
-  const SCEV *ExitCount = PSE->getBackedgeTakenCount();
-  if (isa<SCEVCouldNotCompute>(ExitCount)) {
-    recordAnalysis("CantComputeNumberOfIterations")
-        << "could not determine number of loop iterations";
-    LLVM_DEBUG(dbgs() << "LAA: SCEV could not compute the loop exit count.\n");
-    return false;
-  }
-
-  return true;
-}
-
-void LoopAccessInfo::analyzeLoop(AAResults *AA, LoopInfo *LI,
-                                 const TargetLibraryInfo *TLI,
-                                 DominatorTree *DT) {
-  typedef SmallPtrSet<Value*, 16> ValueSet;
-
-  // Holds the Load and Store instructions.
-  SmallVector<LoadInst *, 16> Loads;
-  SmallVector<StoreInst *, 16> Stores;
-
-  // Holds all the different accesses in the loop.
-  unsigned NumReads = 0;
-  unsigned NumReadWrites = 0;
-
-  bool HasComplexMemInst = false;
-
-  // A runtime check is only legal to insert if there are no convergent calls.
-  HasConvergentOp = false;
-
-  PtrRtChecking->Pointers.clear();
-  PtrRtChecking->Need = false;
-
-  const bool IsAnnotatedParallel = TheLoop->isAnnotatedParallel();
-
-  const bool EnableMemAccessVersioningOfLoop =
-      EnableMemAccessVersioning &&
-      !TheLoop->getHeader()->getParent()->hasOptSize();
-
-  // For each block.
-  for (BasicBlock *BB : TheLoop->blocks()) {
-    // Scan the BB and collect legal loads and stores. Also detect any
-    // convergent instructions.
-    for (Instruction &I : *BB) {
-      if (auto *Call = dyn_cast<CallBase>(&I)) {
-        if (Call->isConvergent())
-          HasConvergentOp = true;
-      }
-
-      // With both a non-vectorizable memory instruction and a convergent
-      // operation, found in this loop, no reason to continue the search.
-      if (HasComplexMemInst && HasConvergentOp) {
-        CanVecMem = false;
-        return;
-      }
-
-      // Avoid hitting recordAnalysis multiple times.
-      if (HasComplexMemInst)
-        continue;
-
-      // If this is a load, save it. If this instruction can read from memory
-      // but is not a load, then we quit. Notice that we don't handle function
-      // calls that read or write.
-      if (I.mayReadFromMemory()) {
-        // Many math library functions read the rounding mode. We will only
-        // vectorize a loop if it contains known function calls that don't set
-        // the flag. Therefore, it is safe to ignore this read from memory.
-        auto *Call = dyn_cast<CallInst>(&I);
-        if (Call && getVectorIntrinsicIDForCall(Call, TLI))
-          continue;
-
-        // If the function has an explicit vectorized counterpart, we can safely
-        // assume that it can be vectorized.
-        if (Call && !Call->isNoBuiltin() && Call->getCalledFunction() &&
-            !VFDatabase::getMappings(*Call).empty())
-          continue;
-
-        auto *Ld = dyn_cast<LoadInst>(&I);
-        if (!Ld) {
-          recordAnalysis("CantVectorizeInstruction", Ld)
-            << "instruction cannot be vectorized";
-          HasComplexMemInst = true;
-          continue;
-        }
-        if (!Ld->isSimple() && !IsAnnotatedParallel) {
-          recordAnalysis("NonSimpleLoad", Ld)
-              << "read with atomic ordering or volatile read";
-          LLVM_DEBUG(dbgs() << "LAA: Found a non-simple load.\n");
-          HasComplexMemInst = true;
-          continue;
-        }
-        NumLoads++;
-        Loads.push_back(Ld);
-        DepChecker->addAccess(Ld);
-        if (EnableMemAccessVersioningOfLoop)
-          collectStridedAccess(Ld);
-        continue;
-      }
-
-      // Save 'store' instructions. Abort if other instructions write to memory.
-      if (I.mayWriteToMemory()) {
-        auto *St = dyn_cast<StoreInst>(&I);
-        if (!St) {
-          recordAnalysis("CantVectorizeInstruction", St)
-              << "instruction cannot be vectorized";
-          HasComplexMemInst = true;
-          continue;
-        }
-        if (!St->isSimple() && !IsAnnotatedParallel) {
-          recordAnalysis("NonSimpleStore", St)
-              << "write with atomic ordering or volatile write";
-          LLVM_DEBUG(dbgs() << "LAA: Found a non-simple store.\n");
-          HasComplexMemInst = true;
-          continue;
-        }
-        NumStores++;
-        Stores.push_back(St);
-        DepChecker->addAccess(St);
-        if (EnableMemAccessVersioningOfLoop)
-          collectStridedAccess(St);
-      }
-    } // Next instr.
-  } // Next block.
-
-  if (HasComplexMemInst) {
-    CanVecMem = false;
-    return;
-  }
-
-  // Now we have two lists that hold the loads and the stores.
-  // Next, we find the pointers that they use.
-
-  // Check if we see any stores. If there are no stores, then we don't
-  // care if the pointers are *restrict*.
-  if (!Stores.size()) {
-    LLVM_DEBUG(dbgs() << "LAA: Found a read-only loop!\n");
-    CanVecMem = true;
-    return;
-  }
-
-  MemoryDepChecker::DepCandidates DependentAccesses;
-  AccessAnalysis Accesses(TheLoop, AA, LI, DependentAccesses, *PSE);
-
-  // Holds the analyzed pointers. We don't want to call getUnderlyingObjects
-  // multiple times on the same object. If the ptr is accessed twice, once
-  // for read and once for write, it will only appear once (on the write
-  // list). This is okay, since we are going to check for conflicts between
-  // writes and between reads and writes, but not between reads and reads.
-  ValueSet Seen;
-
-  // Record uniform store addresses to identify if we have multiple stores
-  // to the same address.
-  ValueSet UniformStores;
-
-  for (StoreInst *ST : Stores) {
-    Value *Ptr = ST->getPointerOperand();
-
-    if (isUniform(Ptr))
-      HasDependenceInvolvingLoopInvariantAddress |=
-          !UniformStores.insert(Ptr).second;
-
-    // If we did *not* see this pointer before, insert it to  the read-write
-    // list. At this phase it is only a 'write' list.
-    if (Seen.insert(Ptr).second) {
-      ++NumReadWrites;
-
-      MemoryLocation Loc = MemoryLocation::get(ST);
-      // The TBAA metadata could have a control dependency on the predication
-      // condition, so we cannot rely on it when determining whether or not we
-      // need runtime pointer checks.
-      if (blockNeedsPredication(ST->getParent(), TheLoop, DT))
-        Loc.AATags.TBAA = nullptr;
-
-      visitPointers(const_cast<Value *>(Loc.Ptr), *TheLoop,
-                    [&Accesses, Loc](Value *Ptr) {
-                      MemoryLocation NewLoc = Loc.getWithNewPtr(Ptr);
-                      Accesses.addStore(NewLoc);
-                    });
-    }
-  }
-
-  if (IsAnnotatedParallel) {
-    LLVM_DEBUG(
-        dbgs() << "LAA: A loop annotated parallel, ignore memory dependency "
-               << "checks.\n");
-    CanVecMem = true;
-    return;
-  }
-
-  for (LoadInst *LD : Loads) {
-    Value *Ptr = LD->getPointerOperand();
-    // If we did *not* see this pointer before, insert it to the
-    // read list. If we *did* see it before, then it is already in
-    // the read-write list. This allows us to vectorize expressions
-    // such as A[i] += x;  Because the address of A[i] is a read-write
-    // pointer. This only works if the index of A[i] is consecutive.
-    // If the address of i is unknown (for example A[B[i]]) then we may
-    // read a few words, modify, and write a few words, and some of the
-    // words may be written to the same address.
-    bool IsReadOnlyPtr = false;
-    if (Seen.insert(Ptr).second ||
-        !getPtrStride(*PSE, LD->getType(), Ptr, TheLoop, SymbolicStrides)) {
-      ++NumReads;
-      IsReadOnlyPtr = true;
-    }
-
-    // See if there is an unsafe dependency between a load to a uniform address and
-    // store to the same uniform address.
-    if (UniformStores.count(Ptr)) {
-      LLVM_DEBUG(dbgs() << "LAA: Found an unsafe dependency between a uniform "
-                           "load and uniform store to the same address!\n");
-      HasDependenceInvolvingLoopInvariantAddress = true;
-    }
-
-    MemoryLocation Loc = MemoryLocation::get(LD);
-    // The TBAA metadata could have a control dependency on the predication
-    // condition, so we cannot rely on it when determining whether or not we
-    // need runtime pointer checks.
-    if (blockNeedsPredication(LD->getParent(), TheLoop, DT))
-      Loc.AATags.TBAA = nullptr;
-
-    visitPointers(const_cast<Value *>(Loc.Ptr), *TheLoop,
-                  [&Accesses, Loc, IsReadOnlyPtr](Value *Ptr) {
-                    MemoryLocation NewLoc = Loc.getWithNewPtr(Ptr);
-                    Accesses.addLoad(NewLoc, IsReadOnlyPtr);
-                  });
-  }
-
-  // If we write (or read-write) to a single destination and there are no
-  // other reads in this loop then is it safe to vectorize.
-  if (NumReadWrites == 1 && NumReads == 0) {
-    LLVM_DEBUG(dbgs() << "LAA: Found a write-only loop!\n");
-    CanVecMem = true;
-    return;
-  }
-
-  // Build dependence sets and check whether we need a runtime pointer bounds
-  // check.
-  Accesses.buildDependenceSets();
-
-  // Find pointers with computable bounds. We are going to use this information
-  // to place a runtime bound check.
-  bool CanDoRTIfNeeded = Accesses.canCheckPtrAtRT(*PtrRtChecking, PSE->getSE(),
-                                                  TheLoop, SymbolicStrides);
-  if (!CanDoRTIfNeeded) {
-    recordAnalysis("CantIdentifyArrayBounds") << "cannot identify array bounds";
-    LLVM_DEBUG(dbgs() << "LAA: We can't vectorize because we can't find "
-                      << "the array bounds.\n");
-    CanVecMem = false;
-    return;
-  }
-
-  LLVM_DEBUG(
-    dbgs() << "LAA: May be able to perform a memory runtime check if needed.\n");
-
-  CanVecMem = true;
-  if (Accesses.isDependencyCheckNeeded()) {
-    LLVM_DEBUG(dbgs() << "LAA: Checking memory dependencies\n");
-    CanVecMem = DepChecker->areDepsSafe(
-        DependentAccesses, Accesses.getDependenciesToCheck(), SymbolicStrides);
-    MaxSafeDepDistBytes = DepChecker->getMaxSafeDepDistBytes();
-
-    if (!CanVecMem && DepChecker->shouldRetryWithRuntimeCheck()) {
-      LLVM_DEBUG(dbgs() << "LAA: Retrying with memory checks\n");
-
-      // Clear the dependency checks. We assume they are not needed.
-      Accesses.resetDepChecks(*DepChecker);
-
-      PtrRtChecking->reset();
-      PtrRtChecking->Need = true;
-
-      auto *SE = PSE->getSE();
-      CanDoRTIfNeeded = Accesses.canCheckPtrAtRT(*PtrRtChecking, SE, TheLoop,
-                                                 SymbolicStrides, true);
-
-      // Check that we found the bounds for the pointer.
-      if (!CanDoRTIfNeeded) {
-        recordAnalysis("CantCheckMemDepsAtRunTime")
-            << "cannot check memory dependencies at runtime";
-        LLVM_DEBUG(dbgs() << "LAA: Can't vectorize with memory checks\n");
-        CanVecMem = false;
-        return;
-      }
-
-      CanVecMem = true;
-    }
-  }
-
-  if (HasConvergentOp) {
-    recordAnalysis("CantInsertRuntimeCheckWithConvergent")
-      << "cannot add control dependency to convergent operation";
-    LLVM_DEBUG(dbgs() << "LAA: We can't vectorize because a runtime check "
-                         "would be needed with a convergent operation\n");
-    CanVecMem = false;
-    return;
-  }
-
-  if (CanVecMem)
-    LLVM_DEBUG(
-        dbgs() << "LAA: No unsafe dependent memory operations in loop.  We"
-               << (PtrRtChecking->Need ? "" : " don't")
-               << " need runtime memory checks.\n");
-  else {
-    recordAnalysis("UnsafeMemDep")
-        << "unsafe dependent memory operations in loop. Use "
-           "#pragma loop distribute(enable) to allow loop distribution "
-           "to attempt to isolate the offending operations into a separate "
-           "loop";
-    LLVM_DEBUG(dbgs() << "LAA: unsafe dependent memory operations in loop\n");
-  }
-}
-
-bool LoopAccessInfo::blockNeedsPredication(BasicBlock *BB, Loop *TheLoop,
-                                           DominatorTree *DT)  {
-  assert(TheLoop->contains(BB) && "Unknown block used");
-
-  // Blocks that do not dominate the latch need predication.
-  BasicBlock* Latch = TheLoop->getLoopLatch();
-  return !DT->dominates(BB, Latch);
-}
-
-OptimizationRemarkAnalysis &LoopAccessInfo::recordAnalysis(StringRef RemarkName,
-                                                           Instruction *I) {
-  assert(!Report && "Multiple reports generated");
-
-  Value *CodeRegion = TheLoop->getHeader();
-  DebugLoc DL = TheLoop->getStartLoc();
-
-  if (I) {
-    CodeRegion = I->getParent();
-    // If there is no debug location attached to the instruction, revert back to
-    // using the loop's.
-    if (I->getDebugLoc())
-      DL = I->getDebugLoc();
-  }
-
-  Report = std::make_unique<OptimizationRemarkAnalysis>(DEBUG_TYPE, RemarkName, DL,
-                                                   CodeRegion);
-  return *Report;
-}
-
-bool LoopAccessInfo::isUniform(Value *V) const {
-  auto *SE = PSE->getSE();
-  // Since we rely on SCEV for uniformity, if the type is not SCEVable, it is
-  // never considered uniform.
-  // TODO: Is this really what we want? Even without FP SCEV, we may want some
-  // trivially loop-invariant FP values to be considered uniform.
-  if (!SE->isSCEVable(V->getType()))
-    return false;
-  return (SE->isLoopInvariant(SE->getSCEV(V), TheLoop));
-}
-
-void LoopAccessInfo::collectStridedAccess(Value *MemAccess) {
-  Value *Ptr = getLoadStorePointerOperand(MemAccess);
-  if (!Ptr)
-    return;
-
-  Value *Stride = getStrideFromPointer(Ptr, PSE->getSE(), TheLoop);
-  if (!Stride)
-    return;
-
-  LLVM_DEBUG(dbgs() << "LAA: Found a strided access that is a candidate for "
-                       "versioning:");
-  LLVM_DEBUG(dbgs() << "  Ptr: " << *Ptr << " Stride: " << *Stride << "\n");
-
-  // Avoid adding the "Stride == 1" predicate when we know that
-  // Stride >= Trip-Count. Such a predicate will effectively optimize a single
-  // or zero iteration loop, as Trip-Count <= Stride == 1.
-  //
-  // TODO: We are currently not making a very informed decision on when it is
-  // beneficial to apply stride versioning. It might make more sense that the
-  // users of this analysis (such as the vectorizer) will trigger it, based on
-  // their specific cost considerations; For example, in cases where stride
-  // versioning does  not help resolving memory accesses/dependences, the
-  // vectorizer should evaluate the cost of the runtime test, and the benefit
-  // of various possible stride specializations, considering the alternatives
-  // of using gather/scatters (if available).
-
-  const SCEV *StrideExpr = PSE->getSCEV(Stride);
-  const SCEV *BETakenCount = PSE->getBackedgeTakenCount();
-
-  // Match the types so we can compare the stride and the BETakenCount.
-  // The Stride can be positive/negative, so we sign extend Stride;
-  // The backedgeTakenCount is non-negative, so we zero extend BETakenCount.
-  const DataLayout &DL = TheLoop->getHeader()->getModule()->getDataLayout();
-  uint64_t StrideTypeSize = DL.getTypeAllocSize(StrideExpr->getType());
-  uint64_t BETypeSize = DL.getTypeAllocSize(BETakenCount->getType());
-  const SCEV *CastedStride = StrideExpr;
-  const SCEV *CastedBECount = BETakenCount;
-  ScalarEvolution *SE = PSE->getSE();
-  if (BETypeSize >= StrideTypeSize)
-    CastedStride = SE->getNoopOrSignExtend(StrideExpr, BETakenCount->getType());
-  else
-    CastedBECount = SE->getZeroExtendExpr(BETakenCount, StrideExpr->getType());
-  const SCEV *StrideMinusBETaken = SE->getMinusSCEV(CastedStride, CastedBECount);
-  // Since TripCount == BackEdgeTakenCount + 1, checking:
-  // "Stride >= TripCount" is equivalent to checking:
-  // Stride - BETakenCount > 0
-  if (SE->isKnownPositive(StrideMinusBETaken)) {
-    LLVM_DEBUG(
-        dbgs() << "LAA: Stride>=TripCount; No point in versioning as the "
-                  "Stride==1 predicate will imply that the loop executes "
-                  "at most once.\n");
-    return;
-  }
-  LLVM_DEBUG(dbgs() << "LAA: Found a strided access that we can version.");
-
-  SymbolicStrides[Ptr] = Stride;
-  StrideSet.insert(Stride);
-}
-
-LoopAccessInfo::LoopAccessInfo(Loop *L, ScalarEvolution *SE,
-                               const TargetLibraryInfo *TLI, AAResults *AA,
-                               DominatorTree *DT, LoopInfo *LI)
-    : PSE(std::make_unique<PredicatedScalarEvolution>(*SE, *L)),
-      PtrRtChecking(std::make_unique<RuntimePointerChecking>(SE)),
-      DepChecker(std::make_unique<MemoryDepChecker>(*PSE, L)), TheLoop(L) {
-  if (canAnalyzeLoop())
-    analyzeLoop(AA, LI, TLI, DT);
-}
-
-void LoopAccessInfo::print(raw_ostream &OS, unsigned Depth) const {
-  if (CanVecMem) {
-    OS.indent(Depth) << "Memory dependences are safe";
-    if (MaxSafeDepDistBytes != -1ULL)
-      OS << " with a maximum dependence distance of " << MaxSafeDepDistBytes
-         << " bytes";
-    if (PtrRtChecking->Need)
-      OS << " with run-time checks";
-    OS << "\n";
-  }
-
-  if (HasConvergentOp)
-    OS.indent(Depth) << "Has convergent operation in loop\n";
-
-  if (Report)
-    OS.indent(Depth) << "Report: " << Report->getMsg() << "\n";
-
-  if (auto *Dependences = DepChecker->getDependences()) {
-    OS.indent(Depth) << "Dependences:\n";
-    for (auto &Dep : *Dependences) {
-      Dep.print(OS, Depth + 2, DepChecker->getMemoryInstructions());
-      OS << "\n";
-    }
-  } else
-    OS.indent(Depth) << "Too many dependences, not recorded\n";
-
-  // List the pair of accesses need run-time checks to prove independence.
-  PtrRtChecking->print(OS, Depth);
-  OS << "\n";
-
-  OS.indent(Depth) << "Non vectorizable stores to invariant address were "
-                   << (HasDependenceInvolvingLoopInvariantAddress ? "" : "not ")
-                   << "found in loop.\n";
-
-  OS.indent(Depth) << "SCEV assumptions:\n";
-  PSE->getUnionPredicate().print(OS, Depth);
-
-  OS << "\n";
-
-  OS.indent(Depth) << "Expressions re-written:\n";
-  PSE->print(OS, Depth);
-}
-
-LoopAccessLegacyAnalysis::LoopAccessLegacyAnalysis() : FunctionPass(ID) {
-  initializeLoopAccessLegacyAnalysisPass(*PassRegistry::getPassRegistry());
-}
-
-const LoopAccessInfo &LoopAccessLegacyAnalysis::getInfo(Loop *L) {
-  auto &LAI = LoopAccessInfoMap[L];
-
-  if (!LAI)
-    LAI = std::make_unique<LoopAccessInfo>(L, SE, TLI, AA, DT, LI);
-
-  return *LAI.get();
-}
-
-void LoopAccessLegacyAnalysis::print(raw_ostream &OS, const Module *M) const {
-  LoopAccessLegacyAnalysis &LAA = *const_cast<LoopAccessLegacyAnalysis *>(this);
-
-  for (Loop *TopLevelLoop : *LI)
-    for (Loop *L : depth_first(TopLevelLoop)) {
-      OS.indent(2) << L->getHeader()->getName() << ":\n";
-      auto &LAI = LAA.getInfo(L);
-      LAI.print(OS, 4);
-    }
-}
-
-bool LoopAccessLegacyAnalysis::runOnFunction(Function &F) {
-  SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
-  auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
-  TLI = TLIP ? &TLIP->getTLI(F) : nullptr;
-  AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
-  DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-  LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
-
-  return false;
-}
-
-void LoopAccessLegacyAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.addRequiredTransitive<ScalarEvolutionWrapperPass>();
-  AU.addRequiredTransitive<AAResultsWrapperPass>();
-  AU.addRequiredTransitive<DominatorTreeWrapperPass>();
-  AU.addRequiredTransitive<LoopInfoWrapperPass>();
-
-  AU.setPreservesAll();
-}
-
-char LoopAccessLegacyAnalysis::ID = 0;
-static const char laa_name[] = "Loop Access Analysis";
-#define LAA_NAME "loop-accesses"
-
-INITIALIZE_PASS_BEGIN(LoopAccessLegacyAnalysis, LAA_NAME, laa_name, false, true)
-INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
-INITIALIZE_PASS_END(LoopAccessLegacyAnalysis, LAA_NAME, laa_name, false, true)
-
-AnalysisKey LoopAccessAnalysis::Key;
-
-LoopAccessInfo LoopAccessAnalysis::run(Loop &L, LoopAnalysisManager &AM,
-                                       LoopStandardAnalysisResults &AR) {
-  return LoopAccessInfo(&L, &AR.SE, &AR.TLI, &AR.AA, &AR.DT, &AR.LI);
-}
-
-namespace llvm {
-
-  Pass *createLAAPass() {
-    return new LoopAccessLegacyAnalysis();
-  }
-
-} // end namespace llvm