[llvm] c4b757b - Revert BCmp Loop Idiom recognition transform (PR43870)

Roman Lebedev via llvm-commits llvm-commits at lists.llvm.org
Mon Nov 4 09:34:57 PST 2019


On Mon, Nov 4, 2019 at 8:31 PM Philip Reames <listmail at philipreames.com> wrote:
>
>
> On 11/2/19 2:48 AM, Roman Lebedev via llvm-commits wrote:
> > Author: Roman Lebedev
> > Date: 2019-11-02T12:48:03+03:00
> > New Revision: c4b757be026150eee32050e120026b03d92eb421
> >
> > URL: https://github.com/llvm/llvm-project/commit/c4b757be026150eee32050e120026b03d92eb421
> > DIFF: https://github.com/llvm/llvm-project/commit/c4b757be026150eee32050e120026b03d92eb421.diff
> >
> > LOG: Revert BCmp Loop Idiom recognition transform (PR43870)
> >
> > As discussed in https://bugs.llvm.org/show_bug.cgi?id=43870,
> > this transform is missing a crucial legality check:
> > the old (non-countable) loop would early-return upon first mismatch,
> > but there is no such guarantee for bcmp/memcmp.
> >
> > We'd need to ensure that [PtrA, PtrA+NBytes) and [PtrB, PtrB+NBytes)
> > are fully dereferenceable memory regions. But that would limit
> > the transform to constant loop trip counts and would further
> > cripple it because dereferenceability analysis is *very* partial.
> Actually, this is less bad than it first sounds.  We have a framework in
> SCEV for computing maximum trip counts even for symbolic ones.  I've
> been (slowly) working towards generalizing an interface for this type of
> the problem (in Loads.h & LoopVectorizer).  If we had another use case,
> we could quite possible push this a ways towards general applicability.
> (There will always be gaps of course.)
Sure, i for sure hope such analysis infrastructure will improve in the future;
i was only talking about the present day status.

Roman.

> > Furthermore, even if all that is done, every single test
> > would need to be rewritten from scratch.
> >
> > So let's just give up.
> >
> > Added:
> >
> >
> > Modified:
> >      llvm/docs/ReleaseNotes.rst
> >      llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
> >
> > Removed:
> >      llvm/test/Transforms/LoopIdiom/bcmp-basic.ll
> >      llvm/test/Transforms/LoopIdiom/bcmp-debugify-remarks.ll
> >      llvm/test/Transforms/LoopIdiom/bcmp-negative-tests.ll
> >      llvm/test/Transforms/LoopIdiom/bcmp-widening.ll
> >
> >
> > ################################################################################
> > diff  --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
> > index 1f7374810ced..74fe35c89874 100644
> > --- a/llvm/docs/ReleaseNotes.rst
> > +++ b/llvm/docs/ReleaseNotes.rst
> > @@ -81,9 +81,6 @@ Non-comprehensive list of changes in this release
> >     Undefined Behaviour Sanitizer ``-fsanitize=pointer-overflow`` check
> >     will now catch such cases.
> >
> > -* The Loop Idiom Recognition (``-loop-idiom``) pass has learned to recognize
> > -  ``bcmp`` pattern, and convert it into a call to ``bcmp`` (or ``memcmp``)
> > -  function.
> >
> >   * Windows Control Flow Guard: the ``-cfguard`` option now emits CFG checks on
> >     indirect function calls. The previous behavior is still available with the
> >
> > diff  --git a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
> > index dd477e800693..7679917da5ae 100644
> > --- a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
> > +++ b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
> > @@ -41,7 +41,6 @@
> >   #include "llvm/ADT/ArrayRef.h"
> >   #include "llvm/ADT/DenseMap.h"
> >   #include "llvm/ADT/MapVector.h"
> > -#include "llvm/ADT/STLExtras.h"
> >   #include "llvm/ADT/SetVector.h"
> >   #include "llvm/ADT/SmallPtrSet.h"
> >   #include "llvm/ADT/SmallVector.h"
> > @@ -78,20 +77,16 @@
> >   #include "llvm/IR/LLVMContext.h"
> >   #include "llvm/IR/Module.h"
> >   #include "llvm/IR/PassManager.h"
> > -#include "llvm/IR/PatternMatch.h"
> >   #include "llvm/IR/Type.h"
> >   #include "llvm/IR/User.h"
> >   #include "llvm/IR/Value.h"
> >   #include "llvm/IR/ValueHandle.h"
> > -#include "llvm/IR/Verifier.h"
> >   #include "llvm/Pass.h"
> >   #include "llvm/Support/Casting.h"
> >   #include "llvm/Support/CommandLine.h"
> >   #include "llvm/Support/Debug.h"
> >   #include "llvm/Support/raw_ostream.h"
> >   #include "llvm/Transforms/Scalar.h"
> > -#include "llvm/Transforms/Scalar/LoopPassManager.h"
> > -#include "llvm/Transforms/Utils/BasicBlockUtils.h"
> >   #include "llvm/Transforms/Utils/BuildLibCalls.h"
> >   #include "llvm/Transforms/Utils/Local.h"
> >   #include "llvm/Transforms/Utils/LoopUtils.h"
> > @@ -107,7 +102,6 @@ using namespace llvm;
> >
> >   STATISTIC(NumMemSet, "Number of memset's formed from loop stores");
> >   STATISTIC(NumMemCpy, "Number of memcpy's formed from loop load+stores");
> > -STATISTIC(NumBCmp, "Number of memcmp's formed from loop 2xload+eq-compare");
> >
> >   static cl::opt<bool> UseLIRCodeSizeHeurs(
> >       "use-lir-code-size-heurs",
> > @@ -117,26 +111,6 @@ static cl::opt<bool> UseLIRCodeSizeHeurs(
> >
> >   namespace {
> >
> > -// FIXME: reinventing the wheel much? Is there a cleaner solution?
> > -struct PMAbstraction {
> > -  virtual void markLoopAsDeleted(Loop *L) = 0;
> > -  virtual ~PMAbstraction() = default;
> > -};
> > -struct LegacyPMAbstraction : PMAbstraction {
> > -  LPPassManager &LPM;
> > -  LegacyPMAbstraction(LPPassManager &LPM) : LPM(LPM) {}
> > -  virtual ~LegacyPMAbstraction() = default;
> > -  void markLoopAsDeleted(Loop *L) override { LPM.markLoopAsDeleted(*L); }
> > -};
> > -struct NewPMAbstraction : PMAbstraction {
> > -  LPMUpdater &Updater;
> > -  NewPMAbstraction(LPMUpdater &Updater) : Updater(Updater) {}
> > -  virtual ~NewPMAbstraction() = default;
> > -  void markLoopAsDeleted(Loop *L) override {
> > -    Updater.markLoopAsDeleted(*L, L->getName());
> > -  }
> > -};
> > -
> >   class LoopIdiomRecognize {
> >     Loop *CurLoop = nullptr;
> >     AliasAnalysis *AA;
> > @@ -146,7 +120,6 @@ class LoopIdiomRecognize {
> >     TargetLibraryInfo *TLI;
> >     const TargetTransformInfo *TTI;
> >     const DataLayout *DL;
> > -  PMAbstraction &LoopDeleter;
> >     OptimizationRemarkEmitter &ORE;
> >     bool ApplyCodeSizeHeuristics;
> >
> > @@ -155,10 +128,9 @@ class LoopIdiomRecognize {
> >                                 LoopInfo *LI, ScalarEvolution *SE,
> >                                 TargetLibraryInfo *TLI,
> >                                 const TargetTransformInfo *TTI,
> > -                              const DataLayout *DL, PMAbstraction &LoopDeleter,
> > +                              const DataLayout *DL,
> >                                 OptimizationRemarkEmitter &ORE)
> > -      : AA(AA), DT(DT), LI(LI), SE(SE), TLI(TLI), TTI(TTI), DL(DL),
> > -        LoopDeleter(LoopDeleter), ORE(ORE) {}
> > +      : AA(AA), DT(DT), LI(LI), SE(SE), TLI(TLI), TTI(TTI), DL(DL), ORE(ORE) {}
> >
> >     bool runOnLoop(Loop *L);
> >
> > @@ -172,8 +144,6 @@ class LoopIdiomRecognize {
> >     bool HasMemset;
> >     bool HasMemsetPattern;
> >     bool HasMemcpy;
> > -  bool HasMemCmp;
> > -  bool HasBCmp;
> >
> >     /// Return code for isLegalStore()
> >     enum LegalStoreKind {
> > @@ -216,32 +186,6 @@ class LoopIdiomRecognize {
> >
> >     bool runOnNoncountableLoop();
> >
> > -  struct CmpLoopStructure {
> > -    Value *BCmpValue, *LatchCmpValue;
> > -    BasicBlock *HeaderBrEqualBB, *HeaderBrUnequalBB;
> > -    BasicBlock *LatchBrFinishBB, *LatchBrContinueBB;
> > -  };
> > -  bool matchBCmpLoopStructure(CmpLoopStructure &CmpLoop) const;
> > -  struct CmpOfLoads {
> > -    ICmpInst::Predicate BCmpPred;
> > -    Value *LoadSrcA, *LoadSrcB;
> > -    Value *LoadA, *LoadB;
> > -  };
> > -  bool matchBCmpOfLoads(Value *BCmpValue, CmpOfLoads &CmpOfLoads) const;
> > -  bool recognizeBCmpLoopControlFlow(const CmpOfLoads &CmpOfLoads,
> > -                                    CmpLoopStructure &CmpLoop) const;
> > -  bool recognizeBCmpLoopSCEV(uint64_t BCmpTyBytes, CmpOfLoads &CmpOfLoads,
> > -                             const SCEV *&SrcA, const SCEV *&SrcB,
> > -                             const SCEV *&Iterations) const;
> > -  bool detectBCmpIdiom(ICmpInst *&BCmpInst, CmpInst *&LatchCmpInst,
> > -                       LoadInst *&LoadA, LoadInst *&LoadB, const SCEV *&SrcA,
> > -                       const SCEV *&SrcB, const SCEV *&NBytes) const;
> > -  BasicBlock *transformBCmpControlFlow(ICmpInst *ComparedEqual);
> > -  void transformLoopToBCmp(ICmpInst *BCmpInst, CmpInst *LatchCmpInst,
> > -                           LoadInst *LoadA, LoadInst *LoadB, const SCEV *SrcA,
> > -                           const SCEV *SrcB, const SCEV *NBytes);
> > -  bool recognizeBCmp();
> > -
> >     bool recognizePopcount();
> >     void transformLoopToPopcount(BasicBlock *PreCondBB, Instruction *CntInst,
> >                                  PHINode *CntPhi, Value *Var);
> > @@ -279,14 +223,13 @@ class LoopIdiomRecognizeLegacyPass : public LoopPass {
> >           &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(
> >               *L->getHeader()->getParent());
> >       const DataLayout *DL = &L->getHeader()->getModule()->getDataLayout();
> > -    LegacyPMAbstraction LoopDeleter(LPM);
> >
> >       // For the old PM, we can't use OptimizationRemarkEmitter as an analysis
> >       // pass.  Function analyses need to be preserved across loop transformations
> >       // but ORE cannot be preserved (see comment before the pass definition).
> >       OptimizationRemarkEmitter ORE(L->getHeader()->getParent());
> >
> > -    LoopIdiomRecognize LIR(AA, DT, LI, SE, TLI, TTI, DL, LoopDeleter, ORE);
> > +    LoopIdiomRecognize LIR(AA, DT, LI, SE, TLI, TTI, DL, ORE);
> >       return LIR.runOnLoop(L);
> >     }
> >
> > @@ -305,7 +248,7 @@ char LoopIdiomRecognizeLegacyPass::ID = 0;
> >
> >   PreservedAnalyses LoopIdiomRecognizePass::run(Loop &L, LoopAnalysisManager &AM,
> >                                                 LoopStandardAnalysisResults &AR,
> > -                                              LPMUpdater &Updater) {
> > +                                              LPMUpdater &) {
> >     const auto *DL = &L.getHeader()->getModule()->getDataLayout();
> >
> >     const auto &FAM =
> > @@ -319,9 +262,8 @@ PreservedAnalyses LoopIdiomRecognizePass::run(Loop &L, LoopAnalysisManager &AM,
> >           "LoopIdiomRecognizePass: OptimizationRemarkEmitterAnalysis not cached "
> >           "at a higher level");
> >
> > -  NewPMAbstraction LoopDeleter(Updater);
> >     LoopIdiomRecognize LIR(&AR.AA, &AR.DT, &AR.LI, &AR.SE, &AR.TLI, &AR.TTI, DL,
> > -                         LoopDeleter, *ORE);
> > +                         *ORE);
> >     if (!LIR.runOnLoop(&L))
> >       return PreservedAnalyses::all();
> >
> > @@ -358,8 +300,7 @@ bool LoopIdiomRecognize::runOnLoop(Loop *L) {
> >
> >     // Disable loop idiom recognition if the function's name is a common idiom.
> >     StringRef Name = L->getHeader()->getParent()->getName();
> > -  if (Name == "memset" || Name == "memcpy" || Name == "memcmp" ||
> > -      Name == "bcmp")
> > +  if (Name == "memset" || Name == "memcpy")
> >       return false;
> >
> >     // Determine if code size heuristics need to be applied.
> > @@ -369,10 +310,8 @@ bool LoopIdiomRecognize::runOnLoop(Loop *L) {
> >     HasMemset = TLI->has(LibFunc_memset);
> >     HasMemsetPattern = TLI->has(LibFunc_memset_pattern16);
> >     HasMemcpy = TLI->has(LibFunc_memcpy);
> > -  HasMemCmp = TLI->has(LibFunc_memcmp);
> > -  HasBCmp = TLI->has(LibFunc_bcmp);
> >
> > -  if (HasMemset || HasMemsetPattern || HasMemcpy || HasMemCmp || HasBCmp)
> > +  if (HasMemset || HasMemsetPattern || HasMemcpy)
> >       if (SE->hasLoopInvariantBackedgeTakenCount(L))
> >         return runOnCountableLoop();
> >
> > @@ -1211,7 +1150,7 @@ bool LoopIdiomRecognize::runOnNoncountableLoop() {
> >                       << "] Noncountable Loop %"
> >                       << CurLoop->getHeader()->getName() << "\n");
> >
> > -  return recognizeBCmp() || recognizePopcount() || recognizeAndInsertFFS();
> > +  return recognizePopcount() || recognizeAndInsertFFS();
> >   }
> >
> >   /// Check if the given conditional branch is based on the comparison between
> > @@ -1885,811 +1824,3 @@ void LoopIdiomRecognize::transformLoopToPopcount(BasicBlock *PreCondBB,
> >     //   loop. The loop would otherwise not be deleted even if it becomes empty.
> >     SE->forgetLoop(CurLoop);
> >   }
> > -
> > -bool LoopIdiomRecognize::matchBCmpLoopStructure(
> > -    CmpLoopStructure &CmpLoop) const {
> > -  ICmpInst::Predicate BCmpPred;
> > -
> > -  // We are looking for the following basic layout:
> > -  //  PreheaderBB: <preheader>              ; preds = ???
> > -  //    <...>
> > -  //    br label %LoopHeaderBB
> > -  //  LoopHeaderBB: <header,exiting>        ; preds = %PreheaderBB,%LoopLatchBB
> > -  //    <...>
> > -  //    %BCmpValue = icmp <...>
> > -  //    br i1 %BCmpValue, label %LoopLatchBB, label %Successor0
> > -  //  LoopLatchBB: <latch,exiting>          ; preds = %LoopHeaderBB
> > -  //    <...>
> > -  //    %LatchCmpValue = <are we done, or do next iteration?>
> > -  //    br i1 %LatchCmpValue, label %Successor1, label %LoopHeaderBB
> > -  //  Successor0: <exit>                    ; preds = %LoopHeaderBB
> > -  //    <...>
> > -  //  Successor1: <exit>                    ; preds = %LoopLatchBB
> > -  //    <...>
> > -  //
> > -  // Successor0 and Successor1 may or may not be the same basic block.
> > -
> > -  // Match basic frame-work of this supposedly-comparison loop.
> > -  using namespace PatternMatch;
> > -  if (!match(CurLoop->getHeader()->getTerminator(),
> > -             m_Br(m_CombineAnd(m_ICmp(BCmpPred, m_Value(), m_Value()),
> > -                               m_Value(CmpLoop.BCmpValue)),
> > -                  CmpLoop.HeaderBrEqualBB, CmpLoop.HeaderBrUnequalBB)) ||
> > -      !match(CurLoop->getLoopLatch()->getTerminator(),
> > -             m_Br(m_CombineAnd(m_Cmp(), m_Value(CmpLoop.LatchCmpValue)),
> > -                  CmpLoop.LatchBrFinishBB, CmpLoop.LatchBrContinueBB))) {
> > -    LLVM_DEBUG(dbgs() << "Basic control-flow layout unrecognized.\n");
> > -    return false;
> > -  }
> > -  LLVM_DEBUG(dbgs() << "Recognized basic control-flow layout.\n");
> > -  return true;
> > -}
> > -
> > -bool LoopIdiomRecognize::matchBCmpOfLoads(Value *BCmpValue,
> > -                                          CmpOfLoads &CmpOfLoads) const {
> > -  using namespace PatternMatch;
> > -  LLVM_DEBUG(dbgs() << "Analyzing header icmp " << *BCmpValue
> > -                    << "   as bcmp pattern.\n");
> > -
> > -  // Match bcmp-style loop header cmp. It must be an eq-icmp of loads. Example:
> > -  //    %v0 = load <...>, <...>* %LoadSrcA
> > -  //    %v1 = load <...>, <...>* %LoadSrcB
> > -  //    %CmpLoop.BCmpValue = icmp eq <...> %v0, %v1
> > -  // There won't be any no-op bitcasts between load and icmp,
> > -  // they would have been transformed into a load of bitcast.
> > -  // FIXME: {b,mem}cmp() calls have the same semantics as icmp. Match them too.
> > -  if (!match(BCmpValue,
> > -             m_ICmp(CmpOfLoads.BCmpPred,
> > -                    m_CombineAnd(m_Load(m_Value(CmpOfLoads.LoadSrcA)),
> > -                                 m_Value(CmpOfLoads.LoadA)),
> > -                    m_CombineAnd(m_Load(m_Value(CmpOfLoads.LoadSrcB)),
> > -                                 m_Value(CmpOfLoads.LoadB)))) ||
> > -      !ICmpInst::isEquality(CmpOfLoads.BCmpPred)) {
> > -    LLVM_DEBUG(dbgs() << "Loop header icmp did not match bcmp pattern.\n");
> > -    return false;
> > -  }
> > -  LLVM_DEBUG(dbgs() << "Recognized header icmp as bcmp pattern with loads:\n\t"
> > -                    << *CmpOfLoads.LoadA << "\n\t" << *CmpOfLoads.LoadB
> > -                    << "\n");
> > -  // FIXME: handle memcmp pattern?
> > -  return true;
> > -}
> > -
> > -bool LoopIdiomRecognize::recognizeBCmpLoopControlFlow(
> > -    const CmpOfLoads &CmpOfLoads, CmpLoopStructure &CmpLoop) const {
> > -  BasicBlock *LoopHeaderBB = CurLoop->getHeader();
> > -  BasicBlock *LoopLatchBB = CurLoop->getLoopLatch();
> > -
> > -  // Be wary, comparisons can be inverted, canonicalize order.
> > -  // If this 'element' comparison passed, we expect to proceed to the next elt.
> > -  if (CmpOfLoads.BCmpPred != ICmpInst::Predicate::ICMP_EQ)
> > -    std::swap(CmpLoop.HeaderBrEqualBB, CmpLoop.HeaderBrUnequalBB);
> > -  // The predicate on loop latch does not matter, just canonicalize some order.
> > -  if (CmpLoop.LatchBrContinueBB != LoopHeaderBB)
> > -    std::swap(CmpLoop.LatchBrFinishBB, CmpLoop.LatchBrContinueBB);
> > -
> > -  SmallVector<BasicBlock *, 2> ExitBlocks;
> > -
> > -  CurLoop->getUniqueExitBlocks(ExitBlocks);
> > -  assert(ExitBlocks.size() <= 2U && "Can't have more than two exit blocks.");
> > -
> > -  // Check that control-flow between blocks is as expected.
> > -  if (CmpLoop.HeaderBrEqualBB != LoopLatchBB ||
> > -      CmpLoop.LatchBrContinueBB != LoopHeaderBB ||
> > -      !is_contained(ExitBlocks, CmpLoop.HeaderBrUnequalBB) ||
> > -      !is_contained(ExitBlocks, CmpLoop.LatchBrFinishBB)) {
> > -    LLVM_DEBUG(dbgs() << "Loop control-flow not recognized.\n");
> > -    return false;
> > -  }
> > -
> > -  assert(!is_contained(ExitBlocks, CmpLoop.HeaderBrEqualBB) &&
> > -         !is_contained(ExitBlocks, CmpLoop.LatchBrContinueBB) &&
> > -         "Unexpected exit edges.");
> > -
> > -  LLVM_DEBUG(dbgs() << "Recognized loop control-flow.\n");
> > -
> > -  LLVM_DEBUG(dbgs() << "Performing side-effect analysis on the loop.\n");
> > -  assert(CurLoop->isLCSSAForm(*DT) && "Should only get LCSSA-form loops here.");
> > -  // No loop instructions must be used outside of the loop. Since we are in
> > -  // LCSSA form, we only need to check successor block's PHI nodes's incoming
> > -  // values for incoming blocks that are the loop basic blocks.
> > -  for (const BasicBlock *ExitBB : ExitBlocks) {
> > -    for (const PHINode &PHI : ExitBB->phis()) {
> > -      for (const BasicBlock *LoopBB :
> > -           make_filter_range(PHI.blocks(), [this](BasicBlock *PredecessorBB) {
> > -             return CurLoop->contains(PredecessorBB);
> > -           })) {
> > -        const auto *I =
> > -            dyn_cast<Instruction>(PHI.getIncomingValueForBlock(LoopBB));
> > -        if (I && CurLoop->contains(I)) {
> > -          LLVM_DEBUG(dbgs()
> > -                     << "Loop contains instruction " << *I
> > -                     << "   which is used outside of the loop in basic block  "
> > -                     << ExitBB->getName() << "  in phi node  " << PHI << "\n");
> > -          return false;
> > -        }
> > -      }
> > -    }
> > -  }
> > -  // Similarly, the loop should not have any other observable side-effects
> > -  // other than the final comparison result.
> > -  for (BasicBlock *LoopBB : CurLoop->blocks()) {
> > -    for (Instruction &I : *LoopBB) {
> > -      if (isa<DbgInfoIntrinsic>(I)) // Ignore dbginfo.
> > -        continue;                   // FIXME: anything else? lifetime info?
> > -      if ((I.mayHaveSideEffects() || I.isAtomic() || I.isFenceLike()) &&
> > -          &I != CmpOfLoads.LoadA && &I != CmpOfLoads.LoadB) {
> > -        LLVM_DEBUG(
> > -            dbgs() << "Loop contains instruction with potential side-effects: "
> > -                   << I << "\n");
> > -        return false;
> > -      }
> > -    }
> > -  }
> > -  LLVM_DEBUG(dbgs() << "No loop instructions deemed to have side-effects.\n");
> > -  return true;
> > -}
> > -
> > -bool LoopIdiomRecognize::recognizeBCmpLoopSCEV(uint64_t BCmpTyBytes,
> > -                                               CmpOfLoads &CmpOfLoads,
> > -                                               const SCEV *&SrcA,
> > -                                               const SCEV *&SrcB,
> > -                                               const SCEV *&Iterations) const {
> > -  // Try to compute SCEV of the loads, for this loop's scope.
> > -  const auto *ScevForSrcA = dyn_cast<SCEVAddRecExpr>(
> > -      SE->getSCEVAtScope(CmpOfLoads.LoadSrcA, CurLoop));
> > -  const auto *ScevForSrcB = dyn_cast<SCEVAddRecExpr>(
> > -      SE->getSCEVAtScope(CmpOfLoads.LoadSrcB, CurLoop));
> > -  if (!ScevForSrcA || !ScevForSrcB) {
> > -    LLVM_DEBUG(dbgs() << "Failed to get SCEV expressions for load sources.\n");
> > -    return false;
> > -  }
> > -
> > -  LLVM_DEBUG(dbgs() << "Got SCEV expressions (at loop scope) for loads:\n\t"
> > -                    << *ScevForSrcA << "\n\t" << *ScevForSrcB << "\n");
> > -
> > -  // Loads must have folloving SCEV exprs:  {%ptr,+,BCmpTyBytes}<%LoopHeaderBB>
> > -  const SCEV *RecStepForA = ScevForSrcA->getStepRecurrence(*SE);
> > -  const SCEV *RecStepForB = ScevForSrcB->getStepRecurrence(*SE);
> > -  if (!ScevForSrcA->isAffine() || !ScevForSrcB->isAffine() ||
> > -      ScevForSrcA->getLoop() != CurLoop || ScevForSrcB->getLoop() != CurLoop ||
> > -      RecStepForA != RecStepForB || !isa<SCEVConstant>(RecStepForA) ||
> > -      cast<SCEVConstant>(RecStepForA)->getAPInt() != BCmpTyBytes) {
> > -    LLVM_DEBUG(dbgs() << "Unsupported SCEV expressions for loads. Only support "
> > -                         "affine SCEV expressions originating in the loop we "
> > -                         "are analysing with identical constant positive step, "
> > -                         "equal to the count of bytes compared. Got:\n\t"
> > -                      << *RecStepForA << "\n\t" << *RecStepForB << "\n");
> > -    return false;
> > -    // FIXME: can support BCmpTyBytes > Step.
> > -    // But will need to account for the extra bytes compared at the end.
> > -  }
> > -
> > -  SrcA = ScevForSrcA->getStart();
> > -  SrcB = ScevForSrcB->getStart();
> > -  LLVM_DEBUG(dbgs() << "Got SCEV expressions for load sources:\n\t" << *SrcA
> > -                    << "\n\t" << *SrcB << "\n");
> > -
> > -  // The load sources must be loop-invants that dominate the loop header.
> > -  if (SrcA == SE->getCouldNotCompute() || SrcB == SE->getCouldNotCompute() ||
> > -      !SE->isAvailableAtLoopEntry(SrcA, CurLoop) ||
> > -      !SE->isAvailableAtLoopEntry(SrcB, CurLoop)) {
> > -    LLVM_DEBUG(dbgs() << "Unsupported SCEV expressions for loads, unavaliable "
> > -                         "prior to loop header.\n");
> > -    return false;
> > -  }
> > -
> > -  LLVM_DEBUG(dbgs() << "SCEV expressions for loads are acceptable.\n");
> > -
> > -  // bcmp / memcmp take length argument as size_t, so let's conservatively
> > -  // assume that the iteration count should be not wider than that.
> > -  Type *CmpFuncSizeTy = DL->getIntPtrType(SE->getContext());
> > -
> > -  // For how many iterations is loop guaranteed not to exit via LoopLatch?
> > -  // This is one less than the maximal number of comparisons,and is:  n + -1
> > -  const SCEV *LoopExitCount =
> > -      SE->getExitCount(CurLoop, CurLoop->getLoopLatch());
> > -  LLVM_DEBUG(dbgs() << "Got SCEV expression for loop latch exit count: "
> > -                    << *LoopExitCount << "\n");
> > -  // Exit count, similarly, must be loop-invant that dominates the loop header.
> > -  if (LoopExitCount == SE->getCouldNotCompute() ||
> > -      !LoopExitCount->getType()->isIntOrPtrTy() ||
> > -      LoopExitCount->getType()->getScalarSizeInBits() >
> > -          CmpFuncSizeTy->getScalarSizeInBits() ||
> > -      !SE->isAvailableAtLoopEntry(LoopExitCount, CurLoop)) {
> > -    LLVM_DEBUG(dbgs() << "Unsupported SCEV expression for loop latch exit.\n");
> > -    return false;
> > -  }
> > -
> > -  // LoopExitCount is always one less than the actual count of iterations.
> > -  // Do this before cast, else we will be stuck with   1 + zext(-1 + n)
> > -  Iterations = SE->getAddExpr(
> > -      LoopExitCount, SE->getOne(LoopExitCount->getType()), SCEV::FlagNUW);
> > -  assert(Iterations != SE->getCouldNotCompute() &&
> > -         "Shouldn't fail to increment by one.");
> > -
> > -  LLVM_DEBUG(dbgs() << "Computed iteration count: " << *Iterations << "\n");
> > -  return true;
> > -}
> > -
> > -/// Return true iff the bcmp idiom is detected in the loop.
> > -///
> > -/// Additionally:
> > -/// 1) \p BCmpInst is set to the root byte-comparison instruction.
> > -/// 2) \p LatchCmpInst is set to the comparison that controls the latch.
> > -/// 3) \p LoadA is set to the first  LoadInst.
> > -/// 4) \p LoadB is set to the second LoadInst.
> > -/// 5) \p SrcA is set to the first  source location that is being compared.
> > -/// 6) \p SrcB is set to the second source location that is being compared.
> > -/// 7) \p NBytes is set to the number of bytes to compare.
> > -bool LoopIdiomRecognize::detectBCmpIdiom(ICmpInst *&BCmpInst,
> > -                                         CmpInst *&LatchCmpInst,
> > -                                         LoadInst *&LoadA, LoadInst *&LoadB,
> > -                                         const SCEV *&SrcA, const SCEV *&SrcB,
> > -                                         const SCEV *&NBytes) const {
> > -  LLVM_DEBUG(dbgs() << "Recognizing bcmp idiom\n");
> > -
> > -  // Give up if the loop is not in normal form, or has more than 2 blocks.
> > -  if (!CurLoop->isLoopSimplifyForm() || CurLoop->getNumBlocks() > 2) {
> > -    LLVM_DEBUG(dbgs() << "Basic loop structure unrecognized.\n");
> > -    return false;
> > -  }
> > -  LLVM_DEBUG(dbgs() << "Recognized basic loop structure.\n");
> > -
> > -  CmpLoopStructure CmpLoop;
> > -  if (!matchBCmpLoopStructure(CmpLoop))
> > -    return false;
> > -
> > -  CmpOfLoads CmpOfLoads;
> > -  if (!matchBCmpOfLoads(CmpLoop.BCmpValue, CmpOfLoads))
> > -    return false;
> > -
> > -  if (!recognizeBCmpLoopControlFlow(CmpOfLoads, CmpLoop))
> > -    return false;
> > -
> > -  BCmpInst = cast<ICmpInst>(CmpLoop.BCmpValue);        // FIXME: is there no
> > -  LatchCmpInst = cast<CmpInst>(CmpLoop.LatchCmpValue); // way to combine
> > -  LoadA = cast<LoadInst>(CmpOfLoads.LoadA);            // these cast with
> > -  LoadB = cast<LoadInst>(CmpOfLoads.LoadB);            // m_Value() matcher?
> > -
> > -  Type *BCmpValTy = BCmpInst->getOperand(0)->getType();
> > -  LLVMContext &Context = BCmpValTy->getContext();
> > -  uint64_t BCmpTyBits = DL->getTypeSizeInBits(BCmpValTy);
> > -  static constexpr uint64_t ByteTyBits = 8;
> > -
> > -  LLVM_DEBUG(dbgs() << "Got comparison between values of type " << *BCmpValTy
> > -                    << " of size " << BCmpTyBits
> > -                    << " bits (while byte = " << ByteTyBits << " bits).\n");
> > -  // bcmp()/memcmp() minimal unit of work is a byte. Therefore we must check
> > -  // that we are dealing with a multiple of a byte here.
> > -  if (BCmpTyBits % ByteTyBits != 0) {
> > -    LLVM_DEBUG(dbgs() << "Value size is not a multiple of byte.\n");
> > -    return false;
> > -    // FIXME: could still be done under a run-time check that the total bit
> > -    // count is a multiple of a byte i guess? Or handle remainder separately?
> > -  }
> > -
> > -  // Each comparison is done on this many bytes.
> > -  uint64_t BCmpTyBytes = BCmpTyBits / ByteTyBits;
> > -  LLVM_DEBUG(dbgs() << "Size is exactly " << BCmpTyBytes
> > -                    << " bytes, eligible for bcmp conversion.\n");
> > -
> > -  const SCEV *Iterations;
> > -  if (!recognizeBCmpLoopSCEV(BCmpTyBytes, CmpOfLoads, SrcA, SrcB, Iterations))
> > -    return false;
> > -
> > -  // bcmp / memcmp take length argument as size_t, do promotion now.
> > -  Type *CmpFuncSizeTy = DL->getIntPtrType(Context);
> > -  Iterations = SE->getNoopOrZeroExtend(Iterations, CmpFuncSizeTy);
> > -  assert(Iterations != SE->getCouldNotCompute() && "Promotion failed.");
> > -  // Note that it didn't do ptrtoint cast, we will need to do it manually.
> > -
> > -  // We will be comparing *bytes*, not BCmpTy, we need to recalculate size.
> > -  // It's a multiplication, and it *could* overflow. But for it to overflow
> > -  // we'd want to compare more bytes than could be represented by size_t, But
> > -  // allocation functions also take size_t. So how'd you produce such buffer?
> > -  // FIXME: we likely need to actually check that we know this won't overflow,
> > -  //        via llvm::computeOverflowForUnsignedMul().
> > -  NBytes = SE->getMulExpr(
> > -      Iterations, SE->getConstant(CmpFuncSizeTy, BCmpTyBytes), SCEV::FlagNUW);
> > -  assert(NBytes != SE->getCouldNotCompute() &&
> > -         "Shouldn't fail to increment by one.");
> > -
> > -  LLVM_DEBUG(dbgs() << "Computed total byte count: " << *NBytes << "\n");
> > -
> > -  if (LoadA->getPointerAddressSpace() != LoadB->getPointerAddressSpace() ||
> > -      LoadA->getPointerAddressSpace() != 0 || !LoadA->isSimple() ||
> > -      !LoadB->isSimple()) {
> > -    StringLiteral L("Unsupported loads in idiom - only support identical, "
> > -                    "simple loads from address space 0.\n");
> > -    LLVM_DEBUG(dbgs() << L);
> > -    ORE.emit([&]() {
> > -      return OptimizationRemarkMissed(DEBUG_TYPE, "BCmpIdiomUnsupportedLoads",
> > -                                      BCmpInst->getDebugLoc(),
> > -                                      CurLoop->getHeader())
> > -             << L;
> > -    });
> > -    return false; // FIXME: support non-simple loads.
> > -  }
> > -
> > -  LLVM_DEBUG(dbgs() << "Recognized bcmp idiom\n");
> > -  ORE.emit([&]() {
> > -    return OptimizationRemarkAnalysis(DEBUG_TYPE, "RecognizedBCmpIdiom",
> > -                                      CurLoop->getStartLoc(),
> > -                                      CurLoop->getHeader())
> > -           << "Loop recognized as a bcmp idiom";
> > -  });
> > -
> > -  return true;
> > -}
> > -
> > -BasicBlock *
> > -LoopIdiomRecognize::transformBCmpControlFlow(ICmpInst *ComparedEqual) {
> > -  LLVM_DEBUG(dbgs() << "Transforming control-flow.\n");
> > -  SmallVector<DominatorTree::UpdateType, 8> DTUpdates;
> > -
> > -  BasicBlock *PreheaderBB = CurLoop->getLoopPreheader();
> > -  BasicBlock *HeaderBB = CurLoop->getHeader();
> > -  BasicBlock *LoopLatchBB = CurLoop->getLoopLatch();
> > -  SmallString<32> LoopName = CurLoop->getName();
> > -  Function *Func = PreheaderBB->getParent();
> > -  LLVMContext &Context = Func->getContext();
> > -
> > -  // Before doing anything, drop SCEV info.
> > -  SE->forgetLoop(CurLoop);
> > -
> > -  // Here we start with: (0/6)
> > -  //  PreheaderBB: <preheader>        ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    br label %LoopHeaderBB
> > -  //  LoopHeaderBB: <header,exiting>  ; preds = %PreheaderBB,%LoopLatchBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %LoopLatchBB, label %Successor0BB
> > -  //  LoopLatchBB: <latch,exiting>    ; preds = %LoopHeaderBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %Successor1BB, label %LoopHeaderBB
> > -  //  Successor0BB: <exit>            ; preds = %LoopHeaderBB
> > -  //    %S0PHI = phi <...> [ <...>, %LoopHeaderBB ]
> > -  //    <...>
> > -  //  Successor1BB: <exit>            ; preds = %LoopLatchBB
> > -  //    %S1PHI = phi <...> [ <...>, %LoopLatchBB ]
> > -  //    <...>
> > -  //
> > -  // Successor0 and Successor1 may or may not be the same basic block.
> > -
> > -  // Decouple the edge between loop preheader basic block and loop header basic
> > -  // block. Thus the loop has become unreachable.
> > -  assert(cast<BranchInst>(PreheaderBB->getTerminator())->isUnconditional() &&
> > -         PreheaderBB->getTerminator()->getSuccessor(0) == HeaderBB &&
> > -         "Preheader bb must end with an unconditional branch to header bb.");
> > -  PreheaderBB->getTerminator()->eraseFromParent();
> > -  DTUpdates.push_back({DominatorTree::Delete, PreheaderBB, HeaderBB});
> > -
> > -  // Create a new preheader basic block before loop header basic block.
> > -  auto *PhonyPreheaderBB = BasicBlock::Create(
> > -      Context, LoopName + ".phonypreheaderbb", Func, HeaderBB);
> > -  // And insert an unconditional branch from phony preheader basic block to
> > -  // loop header basic block.
> > -  IRBuilder<>(PhonyPreheaderBB).CreateBr(HeaderBB);
> > -  DTUpdates.push_back({DominatorTree::Insert, PhonyPreheaderBB, HeaderBB});
> > -
> > -  // Create a *single* new empty block that we will substitute as a
> > -  // successor basic block for the loop's exits. This one is temporary.
> > -  // Much like phony preheader basic block, it is not connected.
> > -  auto *PhonySuccessorBB =
> > -      BasicBlock::Create(Context, LoopName + ".phonysuccessorbb", Func,
> > -                         LoopLatchBB->getNextNode());
> > -  // That block must have *some* non-PHI instruction, or else deleteDeadLoop()
> > -  // will mess up cleanup of dbginfo, and verifier will complain.
> > -  IRBuilder<>(PhonySuccessorBB).CreateUnreachable();
> > -
> > -  // Create two new empty blocks that we will use to preserve the original
> > -  // loop exit control-flow, and preserve the incoming values in the PHI nodes
> > -  // in loop's successor exit blocks. These will live one.
> > -  auto *ComparedUnequalBB =
> > -      BasicBlock::Create(Context, ComparedEqual->getName() + ".unequalbb", Func,
> > -                         PhonySuccessorBB->getNextNode());
> > -  auto *ComparedEqualBB =
> > -      BasicBlock::Create(Context, ComparedEqual->getName() + ".equalbb", Func,
> > -                         PhonySuccessorBB->getNextNode());
> > -
> > -  // By now we have: (1/6)
> > -  //  PreheaderBB:                    ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    [no terminator instruction!]
> > -  //  PhonyPreheaderBB: <preheader>   ; No preds, UNREACHABLE!
> > -  //    br label %LoopHeaderBB
> > -  //  LoopHeaderBB: <header,exiting>  ; preds = %PhonyPreheaderBB, %LoopLatchBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %LoopLatchBB, label %Successor0BB
> > -  //  LoopLatchBB: <latch,exiting>    ; preds = %LoopHeaderBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %Successor1BB, label %LoopHeaderBB
> > -  //  PhonySuccessorBB:               ; No preds, UNREACHABLE!
> > -  //    unreachable
> > -  //  EqualBB:                        ; No preds, UNREACHABLE!
> > -  //    [no terminator instruction!]
> > -  //  UnequalBB:                      ; No preds, UNREACHABLE!
> > -  //    [no terminator instruction!]
> > -  //  Successor0BB: <exit>            ; preds = %LoopHeaderBB
> > -  //    %S0PHI = phi <...> [ <...>, %LoopHeaderBB ]
> > -  //    <...>
> > -  //  Successor1BB: <exit>            ; preds = %LoopLatchBB
> > -  //    %S1PHI = phi <...> [ <...>, %LoopLatchBB ]
> > -  //    <...>
> > -
> > -  // What is the mapping/replacement basic block for exiting out of the loop
> > -  // from either of old's loop basic blocks?
> > -  auto GetReplacementBB = [this, ComparedEqualBB,
> > -                           ComparedUnequalBB](const BasicBlock *OldBB) {
> > -    assert(CurLoop->contains(OldBB) && "Only for loop's basic blocks.");
> > -    if (OldBB == CurLoop->getLoopLatch()) // "all elements compared equal".
> > -      return ComparedEqualBB;
> > -    if (OldBB == CurLoop->getHeader()) // "element compared unequal".
> > -      return ComparedUnequalBB;
> > -    llvm_unreachable("Only had two basic blocks in loop.");
> > -  };
> > -
> > -  // What are the exits out of this loop?
> > -  SmallVector<Loop::Edge, 2> LoopExitEdges;
> > -  CurLoop->getExitEdges(LoopExitEdges);
> > -  assert(LoopExitEdges.size() == 2 && "Should have only to two exit edges.");
> > -
> > -  // Populate new basic blocks, update the exiting control-flow, PHI nodes.
> > -  for (const Loop::Edge &Edge : LoopExitEdges) {
> > -    auto *OldLoopBB = const_cast<BasicBlock *>(Edge.first);
> > -    auto *SuccessorBB = const_cast<BasicBlock *>(Edge.second);
> > -    assert(CurLoop->contains(OldLoopBB) && !CurLoop->contains(SuccessorBB) &&
> > -           "Unexpected edge.");
> > -
> > -    // If we would exit the loop from this loop's basic block,
> > -    // what semantically would that mean? Did comparison succeed or fail?
> > -    BasicBlock *NewBB = GetReplacementBB(OldLoopBB);
> > -    assert(NewBB->empty() && "Should not get same new basic block here twice.");
> > -    IRBuilder<> Builder(NewBB);
> > -    Builder.SetCurrentDebugLocation(OldLoopBB->getTerminator()->getDebugLoc());
> > -    Builder.CreateBr(SuccessorBB);
> > -    DTUpdates.push_back({DominatorTree::Insert, NewBB, SuccessorBB});
> > -    // Also, be *REALLY* careful with PHI nodes in successor basic block,
> > -    // update them to recieve the same input value, but not from current loop's
> > -    // basic block, but from new basic block instead.
> > -    SuccessorBB->replacePhiUsesWith(OldLoopBB, NewBB);
> > -    // Also, change loop control-flow. This loop's basic block shall no longer
> > -    // exit from the loop to it's original successor basic block, but to our new
> > -    // phony successor basic block. Note that new successor will be unique exit.
> > -    OldLoopBB->getTerminator()->replaceSuccessorWith(SuccessorBB,
> > -                                                     PhonySuccessorBB);
> > -    DTUpdates.push_back({DominatorTree::Delete, OldLoopBB, SuccessorBB});
> > -    DTUpdates.push_back({DominatorTree::Insert, OldLoopBB, PhonySuccessorBB});
> > -  }
> > -
> > -  // Inform DomTree about edge changes. Note that LoopInfo is still out-of-date.
> > -  assert(DTUpdates.size() == 8 && "Update count prediction failed.");
> > -  DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Eager);
> > -  DTU.applyUpdates(DTUpdates);
> > -  DTUpdates.clear();
> > -
> > -  // By now we have: (2/6)
> > -  //  PreheaderBB:                    ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    [no terminator instruction!]
> > -  //  PhonyPreheaderBB: <preheader>   ; No preds, UNREACHABLE!
> > -  //    br label %LoopHeaderBB
> > -  //  LoopHeaderBB: <header,exiting>  ; preds = %PhonyPreheaderBB, %LoopLatchBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %LoopLatchBB, label %PhonySuccessorBB
> > -  //  LoopLatchBB: <latch,exiting>    ; preds = %LoopHeaderBB
> > -  //    <...>
> > -  //    br i1 %<...>, label %PhonySuccessorBB, label %LoopHeaderBB
> > -  //  PhonySuccessorBB: <uniq. exit>  ; preds = %LoopHeaderBB, %LoopLatchBB
> > -  //    unreachable
> > -  //  EqualBB:                        ; No preds, UNREACHABLE!
> > -  //    br label %Successor1BB
> > -  //  UnequalBB:                      ; No preds, UNREACHABLE!
> > -  //    br label %Successor0BB
> > -  //  Successor0BB:                   ; preds = %UnequalBB
> > -  //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -  //    <...>
> > -  //  Successor1BB:                   ; preds = %EqualBB
> > -  //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -  //    <...>
> > -
> > -  // *Finally*, zap the original loop. Record it's parent loop though.
> > -  Loop *ParentLoop = CurLoop->getParentLoop();
> > -  LLVM_DEBUG(dbgs() << "Deleting old loop.\n");
> > -  LoopDeleter.markLoopAsDeleted(CurLoop); // Mark as deleted *BEFORE* deleting!
> > -  deleteDeadLoop(CurLoop, DT, SE, LI);    // And actually delete the loop.
> > -  CurLoop = nullptr;
> > -
> > -  // By now we have: (3/6)
> > -  //  PreheaderBB:                    ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    [no terminator instruction!]
> > -  //  PhonyPreheaderBB:               ; No preds, UNREACHABLE!
> > -  //    br label %PhonySuccessorBB
> > -  //  PhonySuccessorBB:               ; preds = %PhonyPreheaderBB
> > -  //    unreachable
> > -  //  EqualBB:                        ; No preds, UNREACHABLE!
> > -  //    br label %Successor1BB
> > -  //  UnequalBB:                      ; No preds, UNREACHABLE!
> > -  //    br label %Successor0BB
> > -  //  Successor0BB:                   ; preds = %UnequalBB
> > -  //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -  //    <...>
> > -  //  Successor1BB:                   ; preds = %EqualBB
> > -  //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -  //    <...>
> > -
> > -  // Now, actually restore the CFG.
> > -
> > -  // Insert an unconditional branch from an actual preheader basic block to
> > -  // phony preheader basic block.
> > -  IRBuilder<>(PreheaderBB).CreateBr(PhonyPreheaderBB);
> > -  DTUpdates.push_back({DominatorTree::Insert, PhonyPreheaderBB, HeaderBB});
> > -  // Insert proper conditional branch from phony successor basic block to the
> > -  // "dispatch" basic blocks, which were used to preserve incoming values in
> > -  // original loop's successor basic blocks.
> > -  assert(isa<UnreachableInst>(PhonySuccessorBB->getTerminator()) &&
> > -         "Yep, that's the one we created to keep deleteDeadLoop() happy.");
> > -  PhonySuccessorBB->getTerminator()->eraseFromParent();
> > -  {
> > -    IRBuilder<> Builder(PhonySuccessorBB);
> > -    Builder.SetCurrentDebugLocation(ComparedEqual->getDebugLoc());
> > -    Builder.CreateCondBr(ComparedEqual, ComparedEqualBB, ComparedUnequalBB);
> > -  }
> > -  DTUpdates.push_back(
> > -      {DominatorTree::Insert, PhonySuccessorBB, ComparedEqualBB});
> > -  DTUpdates.push_back(
> > -      {DominatorTree::Insert, PhonySuccessorBB, ComparedUnequalBB});
> > -
> > -  BasicBlock *DispatchBB = PhonySuccessorBB;
> > -  DispatchBB->setName(LoopName + ".bcmpdispatchbb");
> > -
> > -  assert(DTUpdates.size() == 3 && "Update count prediction failed.");
> > -  DTU.applyUpdates(DTUpdates);
> > -  DTUpdates.clear();
> > -
> > -  // By now we have: (4/6)
> > -  //  PreheaderBB:                    ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    br label %PhonyPreheaderBB
> > -  //  PhonyPreheaderBB:               ; preds = %PreheaderBB
> > -  //    br label %DispatchBB
> > -  //  DispatchBB:                     ; preds = %PhonyPreheaderBB
> > -  //    br i1 %ComparedEqual, label %EqualBB, label %UnequalBB
> > -  //  EqualBB:                        ; preds = %DispatchBB
> > -  //    br label %Successor1BB
> > -  //  UnequalBB:                      ; preds = %DispatchBB
> > -  //    br label %Successor0BB
> > -  //  Successor0BB:                   ; preds = %UnequalBB
> > -  //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -  //    <...>
> > -  //  Successor1BB:                   ; preds = %EqualBB
> > -  //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -  //    <...>
> > -
> > -  // The basic CFG has been restored! Now let's merge redundant basic blocks.
> > -
> > -  // Merge phony successor basic block into it's only predecessor,
> > -  // phony preheader basic block. It is fully pointlessly redundant.
> > -  MergeBasicBlockIntoOnlyPred(DispatchBB, &DTU);
> > -
> > -  // By now we have: (5/6)
> > -  //  PreheaderBB:                    ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    br label %DispatchBB
> > -  //  DispatchBB:                     ; preds = %PreheaderBB
> > -  //    br i1 %ComparedEqual, label %EqualBB, label %UnequalBB
> > -  //  EqualBB:                        ; preds = %DispatchBB
> > -  //    br label %Successor1BB
> > -  //  UnequalBB:                      ; preds = %DispatchBB
> > -  //    br label %Successor0BB
> > -  //  Successor0BB:                   ; preds = %UnequalBB
> > -  //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -  //    <...>
> > -  //  Successor1BB:                   ; preds = %EqualBB
> > -  //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -  //    <...>
> > -
> > -  // Was this loop nested?
> > -  if (!ParentLoop) {
> > -    // If the loop was *NOT* nested, then let's also merge phony successor
> > -    // basic block into it's only predecessor, preheader basic block.
> > -    // Also, here we need to update LoopInfo.
> > -    LI->removeBlock(PreheaderBB);
> > -    MergeBasicBlockIntoOnlyPred(DispatchBB, &DTU);
> > -
> > -    // By now we have: (6/6)
> > -    //  DispatchBB:                   ; preds = ???
> > -    //    <...>
> > -    //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -    //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -    //    br i1 %ComparedEqual, label %EqualBB, label %UnequalBB
> > -    //  EqualBB:                      ; preds = %DispatchBB
> > -    //    br label %Successor1BB
> > -    //  UnequalBB:                    ; preds = %DispatchBB
> > -    //    br label %Successor0BB
> > -    //  Successor0BB:                 ; preds = %UnequalBB
> > -    //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -    //    <...>
> > -    //  Successor1BB:                 ; preds = %EqualBB
> > -    //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -    //    <...>
> > -
> > -    return DispatchBB;
> > -  }
> > -
> > -  // Otherwise, we need to "preserve" the LoopSimplify form of the deleted loop.
> > -  // To achieve that, we shall keep the preheader basic block (mainly so that
> > -  // the loop header block will be guaranteed to have a predecessor outside of
> > -  // the loop), and create a phony loop with all these new three basic blocks.
> > -  Loop *PhonyLoop = LI->AllocateLoop();
> > -  ParentLoop->addChildLoop(PhonyLoop);
> > -  PhonyLoop->addBasicBlockToLoop(DispatchBB, *LI);
> > -  PhonyLoop->addBasicBlockToLoop(ComparedEqualBB, *LI);
> > -  PhonyLoop->addBasicBlockToLoop(ComparedUnequalBB, *LI);
> > -
> > -  // But we only have a preheader basic block, a header basic block block and
> > -  // two exiting basic blocks. For a proper loop we also need a backedge from
> > -  // non-header basic block to header bb.
> > -  // Let's just add a never-taken branch from both of the exiting basic blocks.
> > -  for (BasicBlock *BB : {ComparedEqualBB, ComparedUnequalBB}) {
> > -    BranchInst *OldTerminator = cast<BranchInst>(BB->getTerminator());
> > -    assert(OldTerminator->isUnconditional() && "That's the one we created.");
> > -    BasicBlock *SuccessorBB = OldTerminator->getSuccessor(0);
> > -
> > -    IRBuilder<> Builder(OldTerminator);
> > -    Builder.SetCurrentDebugLocation(OldTerminator->getDebugLoc());
> > -    Builder.CreateCondBr(ConstantInt::getTrue(Context), SuccessorBB,
> > -                         DispatchBB);
> > -    OldTerminator->eraseFromParent();
> > -    // Yes, the backedge will never be taken. The control-flow is redundant.
> > -    // If it can be simplified further, other passes will take care.
> > -    DTUpdates.push_back({DominatorTree::Delete, BB, SuccessorBB});
> > -    DTUpdates.push_back({DominatorTree::Insert, BB, SuccessorBB});
> > -    DTUpdates.push_back({DominatorTree::Insert, BB, DispatchBB});
> > -  }
> > -  assert(DTUpdates.size() == 6 && "Update count prediction failed.");
> > -  DTU.applyUpdates(DTUpdates);
> > -  DTUpdates.clear();
> > -
> > -  // By now we have: (6/6)
> > -  //  PreheaderBB: <preheader>        ; preds = ???
> > -  //    <...>
> > -  //    %memcmp = call i32 @memcmp(i8* %LoadSrcA, i8* %LoadSrcB, i64 %Nbytes)
> > -  //    %ComparedEqual = icmp eq <...> %memcmp, 0
> > -  //    br label %BCmpDispatchBB
> > -  //  BCmpDispatchBB: <header>        ; preds = %PreheaderBB
> > -  //    br i1 %ComparedEqual, label %EqualBB, label %UnequalBB
> > -  //  EqualBB: <latch,exiting>        ; preds = %BCmpDispatchBB
> > -  //    br i1 %true, label %Successor1BB, label %BCmpDispatchBB
> > -  //  UnequalBB: <latch,exiting>      ; preds = %BCmpDispatchBB
> > -  //    br i1 %true, label %Successor0BB, label %BCmpDispatchBB
> > -  //  Successor0BB:                   ; preds = %UnequalBB
> > -  //    %S0PHI = phi <...> [ <...>, %UnequalBB ]
> > -  //    <...>
> > -  //  Successor1BB:                   ; preds = %EqualBB
> > -  //    %S0PHI = phi <...> [ <...>, %EqualBB ]
> > -  //    <...>
> > -
> > -  // Finally fully DONE!
> > -  return DispatchBB;
> > -}
> > -
> > -void LoopIdiomRecognize::transformLoopToBCmp(ICmpInst *BCmpInst,
> > -                                             CmpInst *LatchCmpInst,
> > -                                             LoadInst *LoadA, LoadInst *LoadB,
> > -                                             const SCEV *SrcA, const SCEV *SrcB,
> > -                                             const SCEV *NBytes) {
> > -  // We will be inserting before the terminator instruction of preheader block.
> > -  IRBuilder<> Builder(CurLoop->getLoopPreheader()->getTerminator());
> > -
> > -  LLVM_DEBUG(dbgs() << "Transforming bcmp loop idiom into a call.\n");
> > -  LLVM_DEBUG(dbgs() << "Emitting new instructions.\n");
> > -
> > -  // Expand the SCEV expressions for both sources to compare, and produce value
> > -  // for the byte len (beware of Iterations potentially being a pointer, and
> > -  // account for element size being BCmpTyBytes bytes, which may be not 1 byte)
> > -  Value *PtrA, *PtrB, *Len;
> > -  {
> > -    SCEVExpander SExp(*SE, *DL, "LoopToBCmp");
> > -    SExp.setInsertPoint(&*Builder.GetInsertPoint());
> > -
> > -    auto HandlePtr = [&SExp](LoadInst *Load, const SCEV *Src) {
> > -      SExp.SetCurrentDebugLocation(DebugLoc());
> > -      // If the pointer operand of original load had dbgloc - use it.
> > -      if (const auto *I = dyn_cast<Instruction>(Load->getPointerOperand()))
> > -        SExp.SetCurrentDebugLocation(I->getDebugLoc());
> > -      return SExp.expandCodeFor(Src);
> > -    };
> > -    PtrA = HandlePtr(LoadA, SrcA);
> > -    PtrB = HandlePtr(LoadB, SrcB);
> > -
> > -    // For len calculation let's use dbgloc for the loop's latch condition.
> > -    Builder.SetCurrentDebugLocation(LatchCmpInst->getDebugLoc());
> > -    SExp.SetCurrentDebugLocation(LatchCmpInst->getDebugLoc());
> > -    Len = SExp.expandCodeFor(NBytes);
> > -
> > -    Type *CmpFuncSizeTy = DL->getIntPtrType(Builder.getContext());
> > -    assert(SE->getTypeSizeInBits(Len->getType()) ==
> > -               DL->getTypeSizeInBits(CmpFuncSizeTy) &&
> > -           "Len should already have the correct size.");
> > -
> > -    // Make sure that iteration count is a number, insert ptrtoint cast if not.
> > -    if (Len->getType()->isPointerTy())
> > -      Len = Builder.CreatePtrToInt(Len, CmpFuncSizeTy);
> > -    assert(Len->getType() == CmpFuncSizeTy && "Should have correct type now.");
> > -
> > -    Len->setName(Len->getName() + ".bytecount");
> > -
> > -    // There is no legality check needed. We want to compare that the memory
> > -    // regions [PtrA, PtrA+Len) and [PtrB, PtrB+Len) are fully identical, equal.
> > -    // For them to be fully equal, they must match bit-by-bit. And likewise,
> > -    // for them to *NOT* be fully equal, they have to
> > diff er just by one bit.
> > -    // The step of comparison (bits compared at once) simply does not matter.
> > -  }
> > -
> > -  // For the rest of new instructions, dbgloc should point at the value cmp.
> > -  Builder.SetCurrentDebugLocation(BCmpInst->getDebugLoc());
> > -
> > -  // Emit the comparison itself.
> > -  auto *CmpCall =
> > -      cast<CallInst>(HasBCmp ? emitBCmp(PtrA, PtrB, Len, Builder, *DL, TLI)
> > -                             : emitMemCmp(PtrA, PtrB, Len, Builder, *DL, TLI));
> > -  // FIXME: add {B,Mem}CmpInst with MemoryCompareInst
> > -  //        (based on MemIntrinsicBase) as base?
> > -  // FIXME: propagate metadata from loads? (alignments, AS, TBAA, ...)
> > -
> > -  // {b,mem}cmp returned 0 if they were equal, or non-zero if not equal.
> > -  auto *ComparedEqual = cast<ICmpInst>(Builder.CreateICmpEQ(
> > -      CmpCall, ConstantInt::get(CmpCall->getType(), 0),
> > -      PtrA->getName() + ".vs." + PtrB->getName() + ".eqcmp"));
> > -
> > -  BasicBlock *BB = transformBCmpControlFlow(ComparedEqual);
> > -  Builder.ClearInsertionPoint();
> > -
> > -  // We're done.
> > -  LLVM_DEBUG(dbgs() << "Transformed loop bcmp idiom into a call.\n");
> > -  ORE.emit([&]() {
> > -    return OptimizationRemark(DEBUG_TYPE, "TransformedBCmpIdiomToCall",
> > -                              CmpCall->getDebugLoc(), BB)
> > -           << "Transformed bcmp idiom into a call to "
> > -           << ore::NV("NewFunction", CmpCall->getCalledFunction())
> > -           << "() function";
> > -  });
> > -  ++NumBCmp;
> > -}
> > -
> > -/// Recognizes a bcmp idiom in a non-countable loop.
> > -///
> > -/// If detected, transforms the relevant code to issue the bcmp (or memcmp)
> > -/// intrinsic function call, and returns true; otherwise, returns false.
> > -bool LoopIdiomRecognize::recognizeBCmp() {
> > -  if (!HasMemCmp && !HasBCmp)
> > -    return false;
> > -
> > -  ICmpInst *BCmpInst;
> > -  CmpInst *LatchCmpInst;
> > -  LoadInst *LoadA, *LoadB;
> > -  const SCEV *SrcA, *SrcB, *NBytes;
> > -  if (!detectBCmpIdiom(BCmpInst, LatchCmpInst, LoadA, LoadB, SrcA, SrcB,
> > -                       NBytes)) {
> > -    LLVM_DEBUG(dbgs() << "bcmp idiom recognition failed.\n");
> > -    return false;
> > -  }
> > -
> > -  transformLoopToBCmp(BCmpInst, LatchCmpInst, LoadA, LoadB, SrcA, SrcB, NBytes);
> > -  return true;
> > -}
> >
> > diff  --git a/llvm/test/Transforms/LoopIdiom/bcmp-basic.ll b/llvm/test/Transforms/LoopIdiom/bcmp-basic.ll
> > deleted file mode 100644
> > index f3b18e9c7562..000000000000
> > --- a/llvm/test/Transforms/LoopIdiom/bcmp-basic.ll
> > +++ /dev/null
> > @@ -1,1819 +0,0 @@
> > -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
> > -; RUN: opt -loop-idiom -verify -verify-each -verify-dom-info -verify-loop-info < %s -S | FileCheck %s
> > -
> > -target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
> > -
> > -; This only tests various forms of loop control-flow.
> > -; These tests are fully identical to bcmp()==0 otherwise.
> > -
> > -; #include <algorithm>
> > -;
> > -; bool pointer_iteration_const_size_no_overlap(char const* ptr) {
> > -;   return std::equal(ptr, ptr + 8, ptr + 8);
> > -; }
> > -; bool pointer_iteration_const_size_partial_overlap(char const* ptr) {
> > -;   return std::equal(ptr, ptr + 16, ptr + 8);
> > -; }
> > -; bool pointer_iteration_const_size_overlap_unknown(char const* ptr0, char const* ptr1) {
> > -;   return std::equal(ptr0, ptr0 + 8, ptr1);
> > -; }
> > -;
> > -; bool pointer_iteration_variable_size_no_overlap(char const* ptr, size_t count) {
> > -;   return std::equal(ptr, ptr + count, ptr + count);
> > -; }
> > -; bool pointer_iteration_variable_size_partial_overlap(char const* ptr, size_t count) {
> > -;   return std::equal(ptr, ptr + 2 * count, ptr + count);
> > -; }
> > -; bool pointer_iteration_variable_size_overlap_unknown(char const* ptr0, char const* ptr1, size_t count) {
> > -;   return std::equal(ptr0, ptr0 + count, ptr1);
> > -; }
> > -;
> > -; bool index_iteration_eq_const_size_no_overlap(char const* ptr) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + 8;
> > -;   for(size_t i = 0; i < 8; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool index_iteration_eq_const_size_partial_overlap(char const* ptr) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + 8;
> > -;   for(size_t i = 0; i < 16; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool index_iteration_eq_const_size_overlap_unknown(char const* ptr0, char const* ptr1) {
> > -;   for(size_t i = 0; i < 8; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool index_iteration_eq_variable_size_no_overlap(char const* ptr, size_t count) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + count;
> > -;   for(size_t i = 0; i < count; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool index_iteration_eq_variable_size_partial_overlap(char const* ptr, size_t count) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + count;
> > -;   for(size_t i = 0; i < 2 * count; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool index_iteration_eq_variable_size_overlap_unknown(char const* ptr0, char const* ptr1, size_t count) {
> > -;   for(size_t i = 0; i < count; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool index_iteration_starting_from_negative(char const* ptr0, char const* ptr1) {
> > -;   for(int i = -4; i < 4; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool combined_iteration_eq_const_size_no_overlap(char const* ptr) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + 8;
> > -;   for(size_t i = 0; i < 8; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool combined_iteration_eq_const_size_partial_overlap(char const* ptr) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + 8;
> > -;   for(size_t i = 0; i < 16; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool combined_iteration_eq_const_size_overlap_unknown(char const* ptr0, char const* ptr1) {
> > -;   for(size_t i = 0; i < 8; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool combined_iteration_eq_variable_size_no_overlap(char const* ptr, size_t count) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + count;
> > -;   for(size_t i = 0; i < count; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool combined_iteration_eq_variable_size_partial_overlap(char const* ptr, size_t count) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + count;
> > -;   for(size_t i = 0; i < 2 * count; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -; bool combined_iteration_eq_variable_size_overlap_unknown(char const* ptr0, char const* ptr1, size_t count) {
> > -;   for(size_t i = 0; i < count; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool negated_pointer_iteration_variable_size_overlap_unknown(char const* ptr0, char const* ptr1, size_t count) {
> > -;   return !std::equal(ptr0, ptr0 + count, ptr1);
> > -; }
> > -;
> > -; bool integer_pointer_iteration_variable_size_overlap_unknown(int const* ptr0, int const* ptr1, size_t count) {
> > -;   return std::equal(ptr0, ptr0 + count, ptr1);
> > -; }
> > -;
> > -; bool small_index_iteration(char const* ptr0, char const* ptr1, int count) {
> > -;   for(int i = 0; i < count; i++, ++ptr0, ++ptr1) {
> > -;     if(*ptr0 != *ptr1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; bool three_pointer_iteration(char const* ptr0, char const* ptr0_end, char const* ptr1) {
> > -;   return std::equal(ptr0, ptr0_end, ptr1);
> > -; }
> > -;
> > -; int value_propagation(char const* ptr0, char const* ptr1, size_t count, int on_equal, int on_unequal) {
> > -;   if(std::equal(ptr0, ptr0 + count, ptr1))
> > -;     return on_equal;
> > -;   return on_unequal;
> > -; }
> > -;
> > -; void callee_on_unequal();
> > -; void callee_on_success();
> > -; void multiple_exit_blocks(char const* ptr0, char const* ptr1, size_t count) {
> > -;   if(!std::equal(ptr0, ptr0 + count, ptr1)) {
> > -;     callee_on_unequal();
> > -;     return;
> > -;   }
> > -;   callee_on_success();
> > -; }
> > -;
> > -; void multiple_phis(char const* ptr0, char const* ptr1, size_t count, char const* v0, char const* v1, char const* v2, char const* v3, char const** out0, char const** out1) {
> > -;   char const *o0, *o1;
> > -;   if(std::equal(ptr0, ptr0 + count, ptr1)) {
> > -;     o0 = v0;
> > -;     o1 = v1;
> > -;   } else {
> > -;     o0 = v2;
> > -;     o1 = v3;
> > -;   }
> > -;   *out0 = o0;
> > -;   *out1 = o1;
> > -; }
> > -;
> > -; void sink(bool);
> > -; void loop_within_loop(size_t outer_count, char const** ptr0, char const** ptr1, size_t* count) {
> > -;   for(size_t i = 0; i != outer_count; ++i)
> > -;     sink(std::equal(ptr0[i], ptr0[i] + count[i], ptr1[i]));
> > -; }
> > -;
> > -; void loop_within_loop_with_multiple_exit_blocks(size_t outer_count, char const** ptr0, char const** ptr1, size_t* count) {
> > -;   for(size_t i = 0; i != outer_count; ++i) {
> > -;     if(!std::equal(ptr0[i], ptr0[i] + count[i], ptr1[i])) {
> > -;       callee_on_unequal();
> > -;       return;
> > -;     }
> > -;     callee_on_success();
> > -;   }
> > -; }
> > -;
> > -; void endless_loop_if_equal(int *a, int *b) {
> > -;   for (;;) {
> > -;     for (int c = 0; c < 4; c++) {
> > -;       if (a[c] != b[c])
> > -;         return;
> > -;     }
> > -;   }
> > -; }
> > -;
> > -; bool load_of_bitcasts(char const* ptr0, float const* ptr1, size_t count) {
> > -;   for(size_t i = 0; i < count; i++, ptr0 += sizeof(float), ptr1++) {
> > -;     int v0, v1;
> > -;     memcpy(&v0, ptr0, sizeof(float));
> > -;     memcpy(&v1, ptr1, sizeof(float));
> > -;     if(v0 != v1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; // FIXME
> > -; bool overlapping_loads(char const* ptr0, char const* ptr1, size_t count) {
> > -;   for(size_t i = 0; i < count; i++, ptr0++, ptr1++) {
> > -;     int v0, v1;
> > -;     memcpy(&v0, ptr0, sizeof(float));
> > -;     memcpy(&v1, ptr1, sizeof(float));
> > -;     if(v0 != v1)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -
> > -define i1 @_Z39pointer_iteration_const_size_no_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z39pointer_iteration_const_size_no_overlapPKc(
> > -; CHECK-NEXT:  for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 8)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.inc.i.i, %entry
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %add.ptr, %entry ]
> > -  %__first1.addr.06.i.i.idx = phi i64 [ %__first1.addr.06.i.i.add, %for.inc.i.i ], [ 0, %entry ]
> > -  %__first1.addr.06.i.i.ptr = getelementptr inbounds i8, i8* %ptr, i64 %__first1.addr.06.i.i.idx
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i.ptr
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %__first1.addr.06.i.i.add = add nuw nsw i64 %__first1.addr.06.i.i.idx, 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i64 %__first1.addr.06.i.i.add, 8
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i
> > -  %retval.0.i.i = phi i1 [ false, %for.body.i.i ], [ true, %for.inc.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z44pointer_iteration_const_size_partial_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z44pointer_iteration_const_size_partial_overlapPKc(
> > -; CHECK-NEXT:  for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR1:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR1]], i64 16)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR1_EQCMP]], label [[PTR_VS_ADD_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr1 = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.inc.i.i, %entry
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %add.ptr1, %entry ]
> > -  %__first1.addr.06.i.i.idx = phi i64 [ %__first1.addr.06.i.i.add, %for.inc.i.i ], [ 0, %entry ]
> > -  %__first1.addr.06.i.i.ptr = getelementptr inbounds i8, i8* %ptr, i64 %__first1.addr.06.i.i.idx
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i.ptr
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %__first1.addr.06.i.i.add = add nuw nsw i64 %__first1.addr.06.i.i.idx, 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i64 %__first1.addr.06.i.i.add, 16
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i
> > -  %retval.0.i.i = phi i1 [ false, %for.body.i.i ], [ true, %for.inc.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z44pointer_iteration_const_size_overlap_unknownPKcS0_(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @_Z44pointer_iteration_const_size_overlap_unknownPKcS0_(
> > -; CHECK-NEXT:  for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 8)
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.inc.i.i, %entry
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i.idx = phi i64 [ %__first1.addr.06.i.i.add, %for.inc.i.i ], [ 0, %entry ]
> > -  %__first1.addr.06.i.i.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %__first1.addr.06.i.i.idx
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i.ptr
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %__first1.addr.06.i.i.add = add nuw nsw i64 %__first1.addr.06.i.i.idx, 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i64 %__first1.addr.06.i.i.add, 8
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i
> > -  %retval.0.i.i = phi i1 [ false, %for.body.i.i ], [ true, %for.inc.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z42pointer_iteration_variable_size_no_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z42pointer_iteration_variable_size_no_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %add.ptr, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr, %entry ]
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ true, %entry ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z47pointer_iteration_variable_size_partial_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z47pointer_iteration_variable_size_partial_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[MUL_BYTECOUNT:%.*]] = shl i64 [[COUNT:%.*]], 1
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[MUL_BYTECOUNT]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[MUL_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR1:%.*]] = getelementptr inbounds i8, i8* [[PTR]], i64 [[COUNT]]
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR1]], i64 [[MUL_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR1_EQCMP]], label [[PTR_VS_ADD_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %mul = shl i64 %count, 1
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %mul
> > -  %cmp5.i.i = icmp eq i64 %mul, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i.preheader
> > -
> > -for.body.i.i.preheader:                           ; preds = %entry
> > -  %add.ptr1 = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.body.i.i.preheader, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %add.ptr1, %for.body.i.i.preheader ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr, %for.body.i.i.preheader ]
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ true, %entry ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z47pointer_iteration_variable_size_overlap_unknownPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z47pointer_iteration_variable_size_overlap_unknownPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %v0 = load i8, i8* %__first1.addr.06.i.i
> > -  %v1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %v0, %v1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ true, %entry ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z40index_iteration_eq_const_size_no_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z40index_iteration_eq_const_size_no_overlapPKc(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 8)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.013 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr, i64 %i.013
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %add.ptr, i64 %i.013
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.013, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.cond, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z45index_iteration_eq_const_size_partial_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z45index_iteration_eq_const_size_partial_overlapPKc(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 16)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.013 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr, i64 %i.013
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %add.ptr, i64 %i.013
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.013, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.cond, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z45index_iteration_eq_const_size_overlap_unknownPKcS0_(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @_Z45index_iteration_eq_const_size_overlap_unknownPKcS0_(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 8)
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.cond, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z43index_iteration_eq_variable_size_no_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z43index_iteration_eq_variable_size_no_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  %cmp14 = icmp eq i64 %count, 0
> > -  br i1 %cmp14, label %cleanup, label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.015 = phi i64 [ %inc, %for.cond ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr, i64 %i.015
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %add.ptr, i64 %i.015
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw i64 %i.015, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.cond, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.cond ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z48index_iteration_eq_variable_size_partial_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z48index_iteration_eq_variable_size_partial_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT:%.*]]
> > -; CHECK-NEXT:    [[MUL_BYTECOUNT:%.*]] = shl i64 [[COUNT]], 1
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[MUL_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[MUL_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  %mul = shl i64 %count, 1
> > -  %cmp14 = icmp eq i64 %mul, 0
> > -  br i1 %cmp14, label %cleanup, label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, %mul
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.015 = phi i64 [ %inc, %for.cond ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr, i64 %i.015
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %add.ptr, i64 %i.015
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw i64 %i.015, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.cond, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.cond ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z48index_iteration_eq_variable_size_overlap_unknownPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z48index_iteration_eq_variable_size_overlap_unknownPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP8:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP8]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp8 = icmp eq i64 %count, 0
> > -  br i1 %cmp8, label %cleanup, label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.09 = phi i64 [ %inc, %for.cond ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.09
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.09
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw i64 %i.09, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.cond, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.cond ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z38index_iteration_starting_from_negativePKcS0_(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @_Z38index_iteration_starting_from_negativePKcS0_(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[SCEVGEP:%.*]] = getelementptr i8, i8* [[PTR0:%.*]], i64 -4
> > -; CHECK-NEXT:    [[SCEVGEP1:%.*]] = getelementptr i8, i8* [[PTR1:%.*]], i64 -4
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[SCEVGEP]], i8* [[SCEVGEP1]], i64 8)
> > -; CHECK-NEXT:    [[SCEVGEP_VS_SCEVGEP1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[SCEVGEP_VS_SCEVGEP1_EQCMP]], label [[SCEVGEP_VS_SCEVGEP1_EQCMP_EQUALBB:%.*]], label [[SCEVGEP_VS_SCEVGEP1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       scevgep.vs.scevgep1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       scevgep.vs.scevgep1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RET:%.*]] = phi i1 [ false, [[SCEVGEP_VS_SCEVGEP1_EQCMP_UNEQUALBB]] ], [ true, [[SCEVGEP_VS_SCEVGEP1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RET]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp slt i64 %indvars.iv.next, 4
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %indvars.iv = phi i64 [ -4, %entry ], [ %indvars.iv.next, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %indvars.iv
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx2 = getelementptr inbounds i8, i8* %ptr1, i64 %indvars.iv
> > -  %v1 = load i8, i8* %arrayidx2
> > -  %cmp4 = icmp eq i8 %v0, %v1
> > -  %indvars.iv.next = add nsw i64 %indvars.iv, 1
> > -  br i1 %cmp4, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.cond, %for.body
> > -  %ret = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %ret
> > -}
> > -
> > -define i1 @_Z43combined_iteration_eq_const_size_no_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z43combined_iteration_eq_const_size_no_overlapPKc(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 8)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %incdec.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw nsw i64 %i.015, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 1
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.inc, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z48combined_iteration_eq_const_size_partial_overlapPKc(i8* %ptr) {
> > -; CHECK-LABEL: @_Z48combined_iteration_eq_const_size_partial_overlapPKc(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 16)
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %incdec.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw nsw i64 %i.015, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 1
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.inc, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z48combined_iteration_eq_const_size_overlap_unknownPKcS0_(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @_Z48combined_iteration_eq_const_size_overlap_unknownPKcS0_(
> > -; CHECK-NEXT:  for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 8)
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.010 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.addr.09 = phi i8* [ %ptr1, %entry ], [ %incdec.ptr3, %for.inc ]
> > -  %ptr0.addr.08 = phi i8* [ %ptr0, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.addr.08
> > -  %v1 = load i8, i8* %ptr1.addr.09
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw nsw i64 %i.010, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.addr.08, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.addr.09, i64 1
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.inc, %for.body
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z46combined_iteration_eq_variable_size_no_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z46combined_iteration_eq_variable_size_no_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT_BYTECOUNT]]
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp14 = icmp eq i64 %count, 0
> > -  br i1 %cmp14, label %cleanup, label %for.body.preheader
> > -
> > -for.body.preheader:                               ; preds = %entry
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  br label %for.body
> > -
> > -for.body:                                         ; preds = %for.body.preheader, %for.inc
> > -  %i.017 = phi i64 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
> > -  %ptr1.016 = phi i8* [ %incdec.ptr3, %for.inc ], [ %add.ptr, %for.body.preheader ]
> > -  %ptr0.015 = phi i8* [ %incdec.ptr, %for.inc ], [ %ptr, %for.body.preheader ]
> > -  %v0 = load i8, i8* %ptr0.015
> > -  %v1 = load i8, i8* %ptr1.016
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.017, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.015, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.016, i64 1
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z51combined_iteration_eq_variable_size_partial_overlapPKcm(i8* %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z51combined_iteration_eq_variable_size_partial_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[MUL_BYTECOUNT:%.*]] = shl i64 [[COUNT:%.*]], 1
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[MUL_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT]]
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[MUL_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %mul = shl i64 %count, 1
> > -  %cmp14 = icmp eq i64 %mul, 0
> > -  br i1 %cmp14, label %cleanup, label %for.body.preheader
> > -
> > -for.body.preheader:                               ; preds = %entry
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  br label %for.body
> > -
> > -for.body:                                         ; preds = %for.body.preheader, %for.inc
> > -  %i.017 = phi i64 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
> > -  %ptr1.016 = phi i8* [ %incdec.ptr3, %for.inc ], [ %add.ptr, %for.body.preheader ]
> > -  %ptr0.015 = phi i8* [ %incdec.ptr, %for.inc ], [ %ptr, %for.body.preheader ]
> > -  %v0 = load i8, i8* %ptr0.015
> > -  %v1 = load i8, i8* %ptr1.016
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.017, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.015, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.016, i64 1
> > -  %cmp = icmp ult i64 %inc, %mul
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z51combined_iteration_eq_variable_size_overlap_unknownPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z51combined_iteration_eq_variable_size_overlap_unknownPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP8:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP8]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp8 = icmp eq i64 %count, 0
> > -  br i1 %cmp8, label %cleanup, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.011 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.010 = phi i8* [ %incdec.ptr3, %for.inc ], [ %ptr1, %entry ]
> > -  %ptr0.addr.09 = phi i8* [ %incdec.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %v0 = load i8, i8* %ptr0.addr.09
> > -  %v1 = load i8, i8* %ptr1.addr.010
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.011, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.addr.09, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.addr.010, i64 1
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @_Z55negated_pointer_iteration_variable_size_overlap_unknownPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z55negated_pointer_iteration_variable_size_overlap_unknownPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ true, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ false, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ false, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %__first1.addr.06.i.i
> > -  %t1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ false, %entry ], [ false, %for.inc.i.i ], [ true, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z55integer_pointer_iteration_variable_size_overlap_unknownPKiS0_m(i32* %ptr0, i32* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z55integer_pointer_iteration_variable_size_overlap_unknownPKiS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i32, i32* [[PTR0:%.*]], i64 [[COUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKIS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[TMP0:%.*]] = shl nsw i64 [[COUNT]], 2
> > -; CHECK-NEXT:    [[TMP1:%.*]] = add i64 [[TMP0]], -4
> > -; CHECK-NEXT:    [[TMP2:%.*]] = lshr i64 [[TMP1]], 2
> > -; CHECK-NEXT:    [[TMP3:%.*]] = shl nuw i64 [[TMP2]], 2
> > -; CHECK-NEXT:    [[DOTBYTECOUNT:%.*]] = add i64 [[TMP3]], 4
> > -; CHECK-NEXT:    [[CSTR:%.*]] = bitcast i32* [[PTR0]] to i8*
> > -; CHECK-NEXT:    [[CSTR1:%.*]] = bitcast i32* [[PTR1:%.*]] to i8*
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[CSTR]], i8* [[CSTR1]], i64 [[DOTBYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKIS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKIS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKIS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKIS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i32, i32* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i32* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i32* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i32, i32* %__first1.addr.06.i.i
> > -  %t1 = load i32, i32* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i32 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i32, i32* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i32, i32* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i32* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKiS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ true, %entry ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i1 @_Z21small_index_iterationPKcS0_i(i8* %ptr0, i8* %ptr1, i32 %count) {
> > -; CHECK-LABEL: @_Z21small_index_iterationPKcS0_i(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP8:%.*]] = icmp sgt i32 [[COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP8]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[DOTBYTECOUNT:%.*]] = zext i32 [[COUNT]] to i64
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 [[DOTBYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[T2_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[T2:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[T2_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[T2]]
> > -;
> > -entry:
> > -  %cmp8 = icmp sgt i32 %count, 0
> > -  br i1 %cmp8, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.011 = phi i32 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.010 = phi i8* [ %incdec.ptr3, %for.inc ], [ %ptr1, %entry ]
> > -  %ptr0.addr.09 = phi i8* [ %incdec.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %ptr0.addr.09
> > -  %t1 = load i8, i8* %ptr1.addr.010
> > -  %cmp2 = icmp eq i8 %t0, %t1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw nsw i32 %i.011, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.addr.09, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.addr.010, i64 1
> > -  %cmp = icmp slt i32 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %t2 = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %t2
> > -}
> > -
> > -define i1 @_Z23three_pointer_iterationPKcS0_S0_(i8* %ptr0, i8* %ptr0_end, i8* %ptr1) {
> > -; CHECK-LABEL: @_Z23three_pointer_iterationPKcS0_S0_(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[PTR01:%.*]] = ptrtoint i8* [[PTR0:%.*]] to i64
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i8* [[PTR0]], [[PTR0_END:%.*]]
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[TMP0:%.*]] = sub i64 0, [[PTR01]]
> > -; CHECK-NEXT:    [[SCEVGEP:%.*]] = getelementptr i8, i8* [[PTR0_END]], i64 [[TMP0]]
> > -; CHECK-NEXT:    [[DOTBYTECOUNT:%.*]] = ptrtoint i8* [[SCEVGEP]] to i64
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[DOTBYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RETVAL_0_I_I]]
> > -;
> > -entry:
> > -  %cmp5.i.i = icmp eq i8* %ptr0, %ptr0_end
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %__first1.addr.06.i.i
> > -  %t1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %ptr0_end
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %entry
> > -  %retval.0.i.i = phi i1 [ true, %entry ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  ret i1 %retval.0.i.i
> > -}
> > -
> > -define i32 @_Z17value_propagationPKcS0_mii(i8* %ptr0, i8* %ptr1, i64 %count, i32 %on_equal, i32 %on_unequal) {
> > -; CHECK-LABEL: @_Z17value_propagationPKcS0_mii(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[T2_PH:%.*]] = phi i32 [ [[ON_UNEQUAL:%.*]], [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ [[ON_EQUAL:%.*]], [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[T2:%.*]] = phi i32 [ [[ON_EQUAL]], [[ENTRY:%.*]] ], [ [[T2_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i32 [[T2]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %__first1.addr.06.i.i
> > -  %t1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.inc.i.i, %for.body.i.i, %entry
> > -  %t2 = phi i32 [ %on_equal, %entry ], [ %on_equal, %for.inc.i.i ], [ %on_unequal, %for.body.i.i ]
> > -  ret i32 %t2
> > -}
> > -
> > -define void @_Z20multiple_exit_blocksPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z20multiple_exit_blocksPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[IF_END:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[IF_END_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[IF_THEN:%.*]]
> > -; CHECK:       if.then:
> > -; CHECK-NEXT:    tail call void @_Z17callee_on_unequalv()
> > -; CHECK-NEXT:    br label [[RETURN:%.*]]
> > -; CHECK:       if.end.loopexit:
> > -; CHECK-NEXT:    br label [[IF_END]]
> > -; CHECK:       if.end:
> > -; CHECK-NEXT:    tail call void @_Z17callee_on_successv()
> > -; CHECK-NEXT:    br label [[RETURN]]
> > -; CHECK:       return:
> > -; CHECK-NEXT:    ret void
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %if.end, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %__first1.addr.06.i.i
> > -  %t1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %if.then
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %if.end, label %for.body.i.i
> > -
> > -if.then:                                          ; preds = %for.body.i.i
> > -  tail call void @_Z17callee_on_unequalv()
> > -  br label %return
> > -
> > -if.end:                                           ; preds = %for.inc.i.i, %entry
> > -  tail call void @_Z17callee_on_successv()
> > -  br label %return
> > -
> > -return:                                           ; preds = %if.end, %if.then
> > -  ret void
> > -}
> > -declare void @_Z17callee_on_unequalv()
> > -declare void @_Z17callee_on_successv()
> > -
> > -define void @_Z13multiple_phisPKcS0_mS0_S0_S0_S0_PS0_S1_(i8* %ptr0, i8* %ptr1, i64 %count, i8* %v0, i8* %v1, i8* %v2, i8* %v3, i8** %out0, i8** %out1) {
> > -; CHECK-LABEL: @_Z13multiple_phisPKcS0_mS0_S0_S0_S0_PS0_S1_(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[COUNT_BYTECOUNT:%.*]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0]], i8* [[PTR1:%.*]], i64 [[COUNT_BYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[T2_PH:%.*]] = phi i8* [ [[V2:%.*]], [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ [[V0:%.*]], [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    [[T3_PH:%.*]] = phi i8* [ [[V3:%.*]], [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ [[V1:%.*]], [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[T2:%.*]] = phi i8* [ [[V0]], [[ENTRY:%.*]] ], [ [[T2_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    [[T3:%.*]] = phi i8* [ [[V1]], [[ENTRY]] ], [ [[T3_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    store i8* [[T2]], i8** [[OUT0:%.*]]
> > -; CHECK-NEXT:    store i8* [[T3]], i8** [[OUT1:%.*]]
> > -; CHECK-NEXT:    ret void
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0, i64 %count
> > -  %cmp5.i.i = icmp eq i64 %count, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %entry, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %ptr1, %entry ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %ptr0, %entry ]
> > -  %t0 = load i8, i8* %__first1.addr.06.i.i
> > -  %t1 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t0, %t1
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.inc.i.i, %for.body.i.i, %entry
> > -  %t2 = phi i8* [ %v0, %entry ], [ %v0, %for.inc.i.i ], [ %v2, %for.body.i.i ]
> > -  %t3 = phi i8* [ %v1, %entry ], [ %v1, %for.inc.i.i ], [ %v3, %for.body.i.i ]
> > -  store i8* %t2, i8** %out0
> > -  store i8* %t3, i8** %out1
> > -  ret void
> > -}
> > -
> > -define void @_Z16loop_within_loopmPPKcS1_Pm(i64 %outer_count, i8** %ptr0, i8** %ptr1, i64* %count) {
> > -; CHECK-LABEL: @_Z16loop_within_loopmPPKcS1_Pm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP11:%.*]] = icmp eq i64 [[OUTER_COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP11]], label [[FOR_COND_CLEANUP:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.cond.cleanup.loopexit:
> > -; CHECK-NEXT:    br label [[FOR_COND_CLEANUP]]
> > -; CHECK:       for.cond.cleanup:
> > -; CHECK-NEXT:    ret void
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_012:%.*]] = phi i64 [ [[INC:%.*]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8*, i8** [[PTR0:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T0:%.*]] = load i8*, i8** [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds i64, i64* [[COUNT:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T1_BYTECOUNT:%.*]] = load i64, i64* [[ARRAYIDX2]]
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[T0]], i64 [[T1_BYTECOUNT]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[T1_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]], label [[FOR_BODY_I_I_PREHEADER:%.*]]
> > -; CHECK:       for.body.i.i.preheader:
> > -; CHECK-NEXT:    [[ARRAYIDX3:%.*]] = getelementptr inbounds i8*, i8** [[PTR1:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T2:%.*]] = load i8*, i8** [[ARRAYIDX3]]
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[T0]], i8* [[T2]], i64 [[T1_BYTECOUNT]])
> > -; CHECK-NEXT:    [[T0_VS_T2_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    br i1 [[T0_VS_T2_EQCMP]], label [[T0_VS_T2_EQCMP_EQUALBB:%.*]], label [[T0_VS_T2_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       t0.vs.t2.eqcmp.equalbb:
> > -; CHECK-NEXT:    br i1 true, label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]]
> > -; CHECK:       t0.vs.t2.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br i1 true, label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[T0_VS_T2_EQCMP_UNEQUALBB]] ], [ true, [[T0_VS_T2_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]]
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[FOR_BODY]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ]
> > -; CHECK-NEXT:    tail call void @_Z4sinkb(i1 [[RETVAL_0_I_I]])
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_012]], 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[INC]], [[OUTER_COUNT]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_COND_CLEANUP_LOOPEXIT:%.*]], label [[FOR_BODY]]
> > -;
> > -entry:
> > -  %cmp11 = icmp eq i64 %outer_count, 0
> > -  br i1 %cmp11, label %for.cond.cleanup, label %for.body
> > -
> > -for.cond.cleanup:                                 ; preds = %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, %entry
> > -  ret void
> > -
> > -for.body:                                         ; preds = %entry, %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -  %i.012 = phi i64 [ %inc, %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8*, i8** %ptr0, i64 %i.012
> > -  %t0 = load i8*, i8** %arrayidx
> > -  %arrayidx2 = getelementptr inbounds i64, i64* %count, i64 %i.012
> > -  %t1 = load i64, i64* %arrayidx2
> > -  %add.ptr = getelementptr inbounds i8, i8* %t0, i64 %t1
> > -  %cmp5.i.i = icmp eq i64 %t1, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i.preheader
> > -
> > -for.body.i.i.preheader:                           ; preds = %for.body
> > -  %arrayidx3 = getelementptr inbounds i8*, i8** %ptr1, i64 %i.012
> > -  %t2 = load i8*, i8** %arrayidx3
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.body.i.i.preheader, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %t2, %for.body.i.i.preheader ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %t0, %for.body.i.i.preheader ]
> > -  %t3 = load i8, i8* %__first1.addr.06.i.i
> > -  %t4 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t3, %t4
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %for.body
> > -  %retval.0.i.i = phi i1 [ true, %for.body ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  tail call void @_Z4sinkb(i1 %retval.0.i.i)
> > -  %inc = add nuw i64 %i.012, 1
> > -  %cmp = icmp eq i64 %inc, %outer_count
> > -  br i1 %cmp, label %for.cond.cleanup, label %for.body
> > -}
> > -declare void @_Z4sinkb(i1)
> > -
> > -define void @_Z42loop_within_loop_with_multiple_exit_blocksmPPKcS1_Pm(i64 %outer_count, i8** %ptr0, i8** %ptr1, i64* %count) {
> > -; CHECK-LABEL: @_Z42loop_within_loop_with_multiple_exit_blocksmPPKcS1_Pm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP11:%.*]] = icmp eq i64 [[OUTER_COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP11]], label [[CLEANUP:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_012:%.*]] = phi i64 [ [[INC:%.*]], [[IF_END:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8*, i8** [[PTR0:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T0:%.*]] = load i8*, i8** [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds i64, i64* [[COUNT:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T1_BYTECOUNT:%.*]] = load i64, i64* [[ARRAYIDX2]]
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[T0]], i64 [[T1_BYTECOUNT]]
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[T1_BYTECOUNT]], 0
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[IF_END]], label [[FOR_BODY_I_I_PREHEADER:%.*]]
> > -; CHECK:       for.body.i.i.preheader:
> > -; CHECK-NEXT:    [[ARRAYIDX3:%.*]] = getelementptr inbounds i8*, i8** [[PTR1:%.*]], i64 [[I_012]]
> > -; CHECK-NEXT:    [[T2:%.*]] = load i8*, i8** [[ARRAYIDX3]]
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[T0]], i8* [[T2]], i64 [[T1_BYTECOUNT]])
> > -; CHECK-NEXT:    [[T0_VS_T2_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    br i1 [[T0_VS_T2_EQCMP]], label [[T0_VS_T2_EQCMP_EQUALBB:%.*]], label [[T0_VS_T2_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       t0.vs.t2.eqcmp.equalbb:
> > -; CHECK-NEXT:    br i1 true, label [[IF_END_LOOPEXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]]
> > -; CHECK:       t0.vs.t2.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br i1 true, label [[IF_THEN:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]]
> > -; CHECK:       if.then:
> > -; CHECK-NEXT:    tail call void @_Z17callee_on_unequalv()
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       if.end.loopexit:
> > -; CHECK-NEXT:    br label [[IF_END]]
> > -; CHECK:       if.end:
> > -; CHECK-NEXT:    tail call void @_Z17callee_on_successv()
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_012]], 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[INC]], [[OUTER_COUNT]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[CLEANUP_LOOPEXIT:%.*]], label [[FOR_BODY]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    ret void
> > -;
> > -entry:
> > -  %cmp11 = icmp eq i64 %outer_count, 0
> > -  br i1 %cmp11, label %cleanup, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %if.end
> > -  %i.012 = phi i64 [ %inc, %if.end ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8*, i8** %ptr0, i64 %i.012
> > -  %t0 = load i8*, i8** %arrayidx
> > -  %arrayidx2 = getelementptr inbounds i64, i64* %count, i64 %i.012
> > -  %t1 = load i64, i64* %arrayidx2
> > -  %add.ptr = getelementptr inbounds i8, i8* %t0, i64 %t1
> > -  %cmp5.i.i = icmp eq i64 %t1, 0
> > -  br i1 %cmp5.i.i, label %if.end, label %for.body.i.i.preheader
> > -
> > -for.body.i.i.preheader:                           ; preds = %for.body
> > -  %arrayidx3 = getelementptr inbounds i8*, i8** %ptr1, i64 %i.012
> > -  %t2 = load i8*, i8** %arrayidx3
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.body.i.i.preheader, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %t2, %for.body.i.i.preheader ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %t0, %for.body.i.i.preheader ]
> > -  %t3 = load i8, i8* %__first1.addr.06.i.i
> > -  %t4 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t3, %t4
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %if.then
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %if.end, label %for.body.i.i
> > -
> > -if.then:                                          ; preds = %for.body.i.i
> > -  tail call void @_Z17callee_on_unequalv()
> > -  br label %cleanup
> > -
> > -if.end:                                           ; preds = %for.inc.i.i, %for.body
> > -  tail call void @_Z17callee_on_successv()
> > -  %inc = add nuw i64 %i.012, 1
> > -  %cmp = icmp eq i64 %inc, %outer_count
> > -  br i1 %cmp, label %cleanup, label %for.body
> > -
> > -cleanup:                                          ; preds = %if.end, %entry, %if.then
> > -  ret void
> > -}
> > -
> > -define void @_Z21endless_loop_if_equalPiS_(i32* %a, i32* %b) {
> > -; CHECK-LABEL: @_Z21endless_loop_if_equalPiS_(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_COND:%.*]]
> > -; CHECK:       for.cond.loopexit:
> > -; CHECK-NEXT:    br label [[FOR_COND]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CSTR:%.*]] = bitcast i32* [[A:%.*]] to i8*
> > -; CHECK-NEXT:    [[CSTR1:%.*]] = bitcast i32* [[B:%.*]] to i8*
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[CSTR]], i8* [[CSTR1]], i64 16)
> > -; CHECK-NEXT:    [[A_VS_B_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    br i1 [[A_VS_B_EQCMP]], label [[A_VS_B_EQCMP_EQUALBB:%.*]], label [[A_VS_B_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       a.vs.b.eqcmp.equalbb:
> > -; CHECK-NEXT:    br i1 true, label [[FOR_COND_LOOPEXIT:%.*]], label [[FOR_BODY_BCMPDISPATCHBB]]
> > -; CHECK:       a.vs.b.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br i1 true, label [[RETURN:%.*]], label [[FOR_BODY_BCMPDISPATCHBB]]
> > -; CHECK:       return:
> > -; CHECK-NEXT:    ret void
> > -;
> > -entry:
> > -  br label %for.cond
> > -
> > -for.cond:                                         ; preds = %for.cond1, %entry
> > -  br label %for.body
> > -
> > -for.cond1:                                        ; preds = %for.body
> > -  %cmp = icmp ult i64 %indvars.iv.next, 4
> > -  br i1 %cmp, label %for.body, label %for.cond
> > -
> > -for.body:                                         ; preds = %for.cond, %for.cond1
> > -  %indvars.iv = phi i64 [ 0, %for.cond ], [ %indvars.iv.next, %for.cond1 ]
> > -  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
> > -  %0 = load i32, i32* %arrayidx
> > -  %arrayidx3 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv
> > -  %1 = load i32, i32* %arrayidx3
> > -  %cmp4 = icmp eq i32 %0, %1
> > -  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
> > -  br i1 %cmp4, label %for.cond1, label %return
> > -
> > -return:                                           ; preds = %for.body
> > -  ret void
> > -}
> > -
> > -define i1 @_Z21load_of_bitcastsPKcPKfm(i8* %ptr0, float* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z21load_of_bitcastsPKcPKfm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP13:%.*]] = icmp eq i64 [[COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP13]], label [[CLEANUP3:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[DOTBYTECOUNT:%.*]] = shl nuw i64 [[COUNT]], 2
> > -; CHECK-NEXT:    [[CSTR:%.*]] = bitcast float* [[PTR1:%.*]] to i8*
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[CSTR]], i64 [[DOTBYTECOUNT]])
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP3_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP3_LOOPEXIT]]
> > -; CHECK:       cleanup3.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ], [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP3]]
> > -; CHECK:       cleanup3:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP3_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp13 = icmp eq i64 %count, 0
> > -  br i1 %cmp13, label %cleanup3, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %ptr0.addr.016 = phi i8* [ %add.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %i.015 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.014 = phi float* [ %incdec.ptr, %for.inc ], [ %ptr1, %entry ]
> > -  %v0.0..sroa_cast = bitcast i8* %ptr0.addr.016 to i32*
> > -  %v0.0.copyload = load i32, i32* %v0.0..sroa_cast
> > -  %v1.0..sroa_cast = bitcast float* %ptr1.addr.014 to i32*
> > -  %v1.0.copyload = load i32, i32* %v1.0..sroa_cast
> > -  %cmp1 = icmp eq i32 %v0.0.copyload, %v1.0.copyload
> > -  br i1 %cmp1, label %for.inc, label %cleanup3
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.015, 1
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0.addr.016, i64 4
> > -  %incdec.ptr = getelementptr inbounds float, float* %ptr1.addr.014, i64 1
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup3
> > -
> > -cleanup3:                                         ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -; FIXME
> > -define i1 @_Z17overlapping_loadsPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z17overlapping_loadsPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP4:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[PTR0_ADDR_017:%.*]] = phi i8* [ [[INCDEC_PTR:%.*]], [[FOR_INC:%.*]] ], [ [[PTR0:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[I_016:%.*]] = phi i64 [ [[INC:%.*]], [[FOR_INC]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[PTR1_ADDR_015:%.*]] = phi i8* [ [[INCDEC_PTR3:%.*]], [[FOR_INC]] ], [ [[PTR1:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[V0_0__SROA_CAST:%.*]] = bitcast i8* [[PTR0_ADDR_017]] to i32*
> > -; CHECK-NEXT:    [[V0_0_COPYLOAD:%.*]] = load i32, i32* [[V0_0__SROA_CAST]]
> > -; CHECK-NEXT:    [[V1_0__SROA_CAST:%.*]] = bitcast i8* [[PTR1_ADDR_015]] to i32*
> > -; CHECK-NEXT:    [[V1_0_COPYLOAD:%.*]] = load i32, i32* [[V1_0__SROA_CAST]]
> > -; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[V0_0_COPYLOAD]], [[V1_0_COPYLOAD]]
> > -; CHECK-NEXT:    br i1 [[CMP1]], label [[FOR_INC]], label [[CLEANUP4_LOOPEXIT:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_016]], 1
> > -; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, i8* [[PTR0_ADDR_017]], i64 1
> > -; CHECK-NEXT:    [[INCDEC_PTR3]] = getelementptr inbounds i8, i8* [[PTR1_ADDR_015]], i64 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], [[COUNT]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP4_LOOPEXIT]]
> > -; CHECK:       cleanup4.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP4]]
> > -; CHECK:       cleanup4:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP4_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp14 = icmp eq i64 %count, 0
> > -  br i1 %cmp14, label %cleanup4, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %ptr0.addr.017 = phi i8* [ %incdec.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %i.016 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.015 = phi i8* [ %incdec.ptr3, %for.inc ], [ %ptr1, %entry ]
> > -  %v0.0..sroa_cast = bitcast i8* %ptr0.addr.017 to i32*
> > -  %v0.0.copyload = load i32, i32* %v0.0..sroa_cast
> > -  %v1.0..sroa_cast = bitcast i8* %ptr1.addr.015 to i32*
> > -  %v1.0.copyload = load i32, i32* %v1.0..sroa_cast
> > -  %cmp1 = icmp eq i32 %v0.0.copyload, %v1.0.copyload
> > -  br i1 %cmp1, label %for.inc, label %cleanup4
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.016, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.addr.017, i64 1
> > -  %incdec.ptr3 = getelementptr inbounds i8, i8* %ptr1.addr.015, i64 1
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup4
> > -
> > -cleanup4:                                         ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @exit_block_is_not_dedicated(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @exit_block_is_not_dedicated(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br i1 true, label [[FOR_BODY_BCMPDISPATCHBB:%.*]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR0:%.*]], i8* [[PTR1:%.*]], i64 8)
> > -; CHECK-NEXT:    [[PTR0_VS_PTR1_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0
> > -; CHECK-NEXT:    br i1 [[PTR0_VS_PTR1_EQCMP]], label [[PTR0_VS_PTR1_EQCMP_EQUALBB:%.*]], label [[PTR0_VS_PTR1_EQCMP_UNEQUALBB:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       ptr0.vs.ptr1.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ true, [[PTR0_VS_PTR1_EQCMP_EQUALBB]] ], [ false, [[PTR0_VS_PTR1_EQCMP_UNEQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br i1 true, label %for.body, label %cleanup
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ], [ false, %entry ]
> > -  ret i1 %res
> > -}
> > -
> > -; With -m32:
> > -; int index_wider_than_pointer(int* a, int* b, long long num) {
> > -;     for(long long i = 0; i < num; ++i) {
> > -;         if(a[i] != b[i])
> > -;             return 1;
> > -;     }
> > -;     return 0;
> > -; }
> > -define dso_local i64 @test(i64* %a, i64* %b, i128 %num) {
> > -; CHECK-LABEL: @test(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP9:%.*]] = icmp sgt i128 [[NUM:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP9]], label [[FOR_BODY_PREHEADER:%.*]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i128 [[INC:%.*]], [[NUM]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_010:%.*]] = phi i128 [ [[INC]], [[FOR_COND:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[IDXPROM:%.*]] = trunc i128 [[I_010]] to i64
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i64, i64* [[A:%.*]], i64 [[IDXPROM]]
> > -; CHECK-NEXT:    [[TMP0:%.*]] = load i64, i64* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds i64, i64* [[B:%.*]], i64 [[IDXPROM]]
> > -; CHECK-NEXT:    [[TMP1:%.*]] = load i64, i64* [[ARRAYIDX2]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i64 [[TMP0]], [[TMP1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i128 [[I_010]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[DOTPH:%.*]] = phi i64 [ 1, [[FOR_BODY]] ], [ 0, [[FOR_COND]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[TMP2:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[DOTPH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i64 [[TMP2]]
> > -;
> > -entry:
> > -  %cmp9 = icmp sgt i128 %num, 0
> > -  br i1 %cmp9, label %for.body, label %cleanup
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp slt i128 %inc, %num
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.010 = phi i128 [ %inc, %for.cond ], [ 0, %entry ]
> > -  %idxprom = trunc i128 %i.010 to i64
> > -  %arrayidx = getelementptr inbounds i64, i64* %a, i64 %idxprom
> > -  %0 = load i64, i64* %arrayidx
> > -  %arrayidx2 = getelementptr inbounds i64, i64* %b, i64 %idxprom
> > -  %1 = load i64, i64* %arrayidx2
> > -  %cmp3 = icmp eq i64 %0, %1
> > -  %inc = add nuw nsw i128 %i.010, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.cond, %entry
> > -  %2 = phi i64 [ 0, %entry ], [ 0, %for.cond ], [ 1, %for.body ]
> > -  ret i64 %2
> > -}
> >
> > diff  --git a/llvm/test/Transforms/LoopIdiom/bcmp-debugify-remarks.ll b/llvm/test/Transforms/LoopIdiom/bcmp-debugify-remarks.ll
> > deleted file mode 100644
> > index d60ef2db0007..000000000000
> > --- a/llvm/test/Transforms/LoopIdiom/bcmp-debugify-remarks.ll
> > +++ /dev/null
> > @@ -1,193 +0,0 @@
> > -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
> > -; RUN: opt -debugify -loop-idiom -pass-remarks=loop-idiom -pass-remarks-analysis=loop-idiom -verify -verify-each -verify-dom-info -verify-loop-info < %s -S 2>&1 | FileCheck %s
> > -
> > -target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
> > -
> > -; Check that everything still works when debuginfo is present, and that it is reasonably propagated.
> > -
> > -; #include <algorithm>
> > -;
> > -; bool index_iteration_eq_variable_size_no_overlap(char const* ptr, size_t count) {
> > -;   char const* ptr0 = ptr;
> > -;   char const* ptr1 = ptr + count;
> > -;   for(size_t i = 0; i < count; i++) {
> > -;     if(ptr0[i] != ptr1[i])
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; void sink(bool);
> > -; void loop_within_loop(size_t outer_count, char const** ptr0, char const** ptr1, size_t* count) {
> > -;   for(size_t i = 0; i != outer_count; ++i)
> > -;     sink(std::equal(ptr0[i], ptr0[i] + count[i], ptr1[i]));
> > -; }
> > -
> > -; CHECK: remark: <stdin>:13:1: Loop recognized as a bcmp idiom
> > -; CHECK: remark: <stdin>:11:1: Transformed bcmp idiom into a call to memcmp() function
> > -; CHECK: remark: <stdin>:29:1: Loop recognized as a bcmp idiom
> > -; CHECK: remark: <stdin>:34:1: Transformed bcmp idiom into a call to memcmp() function
> > -
> > -define i1 @_Z43index_iteration_eq_variable_size_no_overlapPKcm(i8* nocapture %ptr, i64 %count) {
> > -; CHECK-LABEL: @_Z43index_iteration_eq_variable_size_no_overlapPKcm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 [[COUNT_BYTECOUNT:%.*]], !dbg !22
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8* [[ADD_PTR]], metadata !9, metadata !DIExpression()), !dbg !22
> > -; CHECK-NEXT:    [[CMP14:%.*]] = icmp eq i64 [[COUNT_BYTECOUNT]], 0, !dbg !23
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[CMP14]], metadata !11, metadata !DIExpression()), !dbg !23
> > -; CHECK-NEXT:    br i1 [[CMP14]], label [[CLEANUP:%.*]], label [[FOR_BODY_BCMPDISPATCHBB:%.*]], !dbg !24
> > -; CHECK:       for.body.bcmpdispatchbb:
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[PTR]], i8* [[ADD_PTR]], i64 [[COUNT_BYTECOUNT]]), !dbg !25
> > -; CHECK-NEXT:    [[PTR_VS_ADD_PTR_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0, !dbg !25
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !14, metadata !DIExpression()), !dbg !26
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !15, metadata !DIExpression()), !dbg !27
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !16, metadata !DIExpression()), !dbg !28
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !17, metadata !DIExpression()), !dbg !29
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !18, metadata !DIExpression()), !dbg !30
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !19, metadata !DIExpression()), !dbg !25
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !20, metadata !DIExpression()), !dbg !31
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !13, metadata !DIExpression()), !dbg !32
> > -; CHECK-NEXT:    br i1 [[PTR_VS_ADD_PTR_EQCMP]], label [[PTR_VS_ADD_PTR_EQCMP_EQUALBB:%.*]], label [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB:%.*]], !dbg !25
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.equalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT:%.*]], !dbg !33
> > -; CHECK:       ptr.vs.add.ptr.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br label [[CLEANUP_LOOPEXIT]], !dbg !34
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[PTR_VS_ADD_PTR_EQCMP_UNEQUALBB]] ], [ true, [[PTR_VS_ADD_PTR_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]], !dbg !35
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ], !dbg !36
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[RES]], metadata !21, metadata !DIExpression()), !dbg !36
> > -; CHECK-NEXT:    ret i1 [[RES]], !dbg !35
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 %count
> > -  %cmp14 = icmp eq i64 %count, 0
> > -  br i1 %cmp14, label %cleanup, label %for.body
> > -
> > -for.cond:                                         ; preds = %for.body
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -for.body:                                         ; preds = %entry, %for.cond
> > -  %i.015 = phi i64 [ %inc, %for.cond ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr, i64 %i.015
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %add.ptr, i64 %i.015
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw i64 %i.015, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.cond, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.cond ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -define void @_Z16loop_within_loopmPPKcS1_Pm(i64 %outer_count, i8** %ptr0, i8** %ptr1, i64* %count) {
> > -; CHECK-LABEL: @_Z16loop_within_loopmPPKcS1_Pm(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP11:%.*]] = icmp eq i64 [[OUTER_COUNT:%.*]], 0, !dbg !60
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[CMP11]], metadata !39, metadata !DIExpression()), !dbg !60
> > -; CHECK-NEXT:    br i1 [[CMP11]], label [[FOR_COND_CLEANUP:%.*]], label [[FOR_BODY_PREHEADER:%.*]], !dbg !61
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]], !dbg !62
> > -; CHECK:       for.cond.cleanup.loopexit:
> > -; CHECK-NEXT:    br label [[FOR_COND_CLEANUP]], !dbg !63
> > -; CHECK:       for.cond.cleanup:
> > -; CHECK-NEXT:    ret void, !dbg !63
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_012:%.*]] = phi i64 [ [[INC:%.*]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ], !dbg !64
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i64 [[I_012]], metadata !40, metadata !DIExpression()), !dbg !64
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8*, i8** [[PTR0:%.*]], i64 [[I_012]], !dbg !65
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8** [[ARRAYIDX]], metadata !41, metadata !DIExpression()), !dbg !65
> > -; CHECK-NEXT:    [[T0:%.*]] = load i8*, i8** [[ARRAYIDX]], !dbg !66
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8* [[T0]], metadata !42, metadata !DIExpression()), !dbg !66
> > -; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds i64, i64* [[COUNT:%.*]], i64 [[I_012]], !dbg !67
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i64* [[ARRAYIDX2]], metadata !43, metadata !DIExpression()), !dbg !67
> > -; CHECK-NEXT:    [[T1_BYTECOUNT:%.*]] = load i64, i64* [[ARRAYIDX2]], !dbg !68
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i64 [[T1_BYTECOUNT]], metadata !44, metadata !DIExpression()), !dbg !68
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[T0]], i64 [[T1_BYTECOUNT]], !dbg !69
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8* [[ADD_PTR]], metadata !45, metadata !DIExpression()), !dbg !69
> > -; CHECK-NEXT:    [[CMP5_I_I:%.*]] = icmp eq i64 [[T1_BYTECOUNT]], 0, !dbg !70
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[CMP5_I_I]], metadata !46, metadata !DIExpression()), !dbg !70
> > -; CHECK-NEXT:    br i1 [[CMP5_I_I]], label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]], label [[FOR_BODY_I_I_PREHEADER:%.*]], !dbg !62
> > -; CHECK:       for.body.i.i.preheader:
> > -; CHECK-NEXT:    [[ARRAYIDX3:%.*]] = getelementptr inbounds i8*, i8** [[PTR1:%.*]], i64 [[I_012]], !dbg !71
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8** [[ARRAYIDX3]], metadata !47, metadata !DIExpression()), !dbg !71
> > -; CHECK-NEXT:    [[T2:%.*]] = load i8*, i8** [[ARRAYIDX3]], !dbg !72
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i8* [[T2]], metadata !48, metadata !DIExpression()), !dbg !72
> > -; CHECK-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(i8* [[T0]], i8* [[T2]], i64 [[T1_BYTECOUNT]]), !dbg !73
> > -; CHECK-NEXT:    [[T0_VS_T2_EQCMP:%.*]] = icmp eq i32 [[MEMCMP]], 0, !dbg !73
> > -; CHECK-NEXT:    br label [[FOR_BODY_I_I_BCMPDISPATCHBB:%.*]]
> > -; CHECK:       for.body.i.i.bcmpdispatchbb:
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !49, metadata !DIExpression()), !dbg !74
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !50, metadata !DIExpression()), !dbg !75
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !51, metadata !DIExpression()), !dbg !76
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !52, metadata !DIExpression()), !dbg !77
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !53, metadata !DIExpression()), !dbg !73
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !54, metadata !DIExpression()), !dbg !78
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !55, metadata !DIExpression()), !dbg !79
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 undef, metadata !56, metadata !DIExpression()), !dbg !80
> > -; CHECK-NEXT:    br i1 [[T0_VS_T2_EQCMP]], label [[T0_VS_T2_EQCMP_EQUALBB:%.*]], label [[T0_VS_T2_EQCMP_UNEQUALBB:%.*]], !dbg !73
> > -; CHECK:       t0.vs.t2.eqcmp.equalbb:
> > -; CHECK-NEXT:    br i1 true, label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT:%.*]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]], !dbg !81
> > -; CHECK:       t0.vs.t2.eqcmp.unequalbb:
> > -; CHECK-NEXT:    br i1 true, label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]], label [[FOR_BODY_I_I_BCMPDISPATCHBB]], !dbg !82
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit.loopexit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I_PH:%.*]] = phi i1 [ false, [[T0_VS_T2_EQCMP_UNEQUALBB]] ], [ true, [[T0_VS_T2_EQCMP_EQUALBB]] ]
> > -; CHECK-NEXT:    br label [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT]], !dbg !83
> > -; CHECK:       _ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:
> > -; CHECK-NEXT:    [[RETVAL_0_I_I:%.*]] = phi i1 [ true, [[FOR_BODY]] ], [ [[RETVAL_0_I_I_PH]], [[_ZNST3__15EQUALIPKCS2_EEBT_S3_T0__EXIT_LOOPEXIT]] ], !dbg !84
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[RETVAL_0_I_I]], metadata !57, metadata !DIExpression()), !dbg !84
> > -; CHECK-NEXT:    tail call void @_Z4sinkb(i1 [[RETVAL_0_I_I]]), !dbg !83
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_012]], 1, !dbg !85
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i64 [[INC]], metadata !58, metadata !DIExpression()), !dbg !85
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[INC]], [[OUTER_COUNT]], !dbg !86
> > -; CHECK-NEXT:    call void @llvm.dbg.value(metadata i1 [[CMP]], metadata !59, metadata !DIExpression()), !dbg !86
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_COND_CLEANUP_LOOPEXIT:%.*]], label [[FOR_BODY]], !dbg !87
> > -;
> > -entry:
> > -  %cmp11 = icmp eq i64 %outer_count, 0
> > -  br i1 %cmp11, label %for.cond.cleanup, label %for.body
> > -
> > -for.cond.cleanup:                                 ; preds = %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, %entry
> > -  ret void
> > -
> > -for.body:                                         ; preds = %entry, %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -  %i.012 = phi i64 [ %inc, %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit ], [ 0, %entry ]
> > -  %arrayidx = getelementptr inbounds i8*, i8** %ptr0, i64 %i.012
> > -  %t0 = load i8*, i8** %arrayidx
> > -  %arrayidx2 = getelementptr inbounds i64, i64* %count, i64 %i.012
> > -  %t1 = load i64, i64* %arrayidx2
> > -  %add.ptr = getelementptr inbounds i8, i8* %t0, i64 %t1
> > -  %cmp5.i.i = icmp eq i64 %t1, 0
> > -  br i1 %cmp5.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i.preheader
> > -
> > -for.body.i.i.preheader:                           ; preds = %for.body
> > -  %arrayidx3 = getelementptr inbounds i8*, i8** %ptr1, i64 %i.012
> > -  %t2 = load i8*, i8** %arrayidx3
> > -  br label %for.body.i.i
> > -
> > -for.body.i.i:                                     ; preds = %for.body.i.i.preheader, %for.inc.i.i
> > -  %__first2.addr.07.i.i = phi i8* [ %incdec.ptr1.i.i, %for.inc.i.i ], [ %t2, %for.body.i.i.preheader ]
> > -  %__first1.addr.06.i.i = phi i8* [ %incdec.ptr.i.i, %for.inc.i.i ], [ %t0, %for.body.i.i.preheader ]
> > -  %t3 = load i8, i8* %__first1.addr.06.i.i
> > -  %t4 = load i8, i8* %__first2.addr.07.i.i
> > -  %cmp.i.i.i = icmp eq i8 %t3, %t4
> > -  br i1 %cmp.i.i.i, label %for.inc.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit
> > -
> > -for.inc.i.i:                                      ; preds = %for.body.i.i
> > -  %incdec.ptr.i.i = getelementptr inbounds i8, i8* %__first1.addr.06.i.i, i64 1
> > -  %incdec.ptr1.i.i = getelementptr inbounds i8, i8* %__first2.addr.07.i.i, i64 1
> > -  %cmp.i.i = icmp eq i8* %incdec.ptr.i.i, %add.ptr
> > -  br i1 %cmp.i.i, label %_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit, label %for.body.i.i
> > -
> > -_ZNSt3__15equalIPKcS2_EEbT_S3_T0_.exit:           ; preds = %for.body.i.i, %for.inc.i.i, %for.body
> > -  %retval.0.i.i = phi i1 [ true, %for.body ], [ true, %for.inc.i.i ], [ false, %for.body.i.i ]
> > -  tail call void @_Z4sinkb(i1 %retval.0.i.i)
> > -  %inc = add nuw i64 %i.012, 1
> > -  %cmp = icmp eq i64 %inc, %outer_count
> > -  br i1 %cmp, label %for.cond.cleanup, label %for.body
> > -}
> > -declare void @_Z4sinkb(i1)
> >
> > diff  --git a/llvm/test/Transforms/LoopIdiom/bcmp-negative-tests.ll b/llvm/test/Transforms/LoopIdiom/bcmp-negative-tests.ll
> > deleted file mode 100644
> > index e35821bfb012..000000000000
> > --- a/llvm/test/Transforms/LoopIdiom/bcmp-negative-tests.ll
> > +++ /dev/null
> > @@ -1,999 +0,0 @@
> > -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
> > -; RUN: opt -loop-idiom -verify -verify-each -verify-dom-info -verify-loop-info < %s -S | FileCheck %s --implicit-check-not=bcmp --implicit-check-not=memcmp
> > -
> > -; CHECK: source_filename
> > -
> > -target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
> > -
> > -define i1 @three_blocks_and_two_latches_in_loop(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @three_blocks_and_two_latches_in_loop(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[I_08_BE:%.*]], [[FOR_BODY_BACKEDGE:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC:%.*]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_PASSTHROUGH:%.*]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.passthrough:
> > -; CHECK-NEXT:    br i1 true, label [[FOR_COND:%.*]], label [[FOR_BODY_BACKEDGE]]
> > -; CHECK:       for.body.backedge:
> > -; CHECK-NEXT:    [[I_08_BE]] = phi i64 [ [[INC]], [[FOR_COND]] ], [ 0, [[FOR_PASSTHROUGH]] ]
> > -; CHECK-NEXT:    br label [[FOR_BODY]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY_BACKEDGE]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ], [ 0, %for.passthrough ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.passthrough, label %cleanup
> > -
> > -for.passthrough:
> > -  br i1 true, label %for.cond, label %for.body
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @three_blocks_in_loop(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @three_blocks_in_loop(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_PASSTHROUGH:%.*]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.passthrough:
> > -; CHECK-NEXT:    br label [[FOR_COND]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.passthrough, label %cleanup
> > -
> > -for.passthrough:
> > -  br label %for.cond
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @body_cmp_is_not_equality(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @body_cmp_is_not_equality(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp ult i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp ult i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @only_one_load(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @only_one_load(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], 0
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %cmp3 = icmp eq i8 %v0, 0
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @loads_of_less_than_byte(i7* %ptr0, i7* %ptr1) {
> > -; CHECK-LABEL: @loads_of_less_than_byte(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i7, i7* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i7, i7* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i7, i7* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i7, i7* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp ult i7 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i7, i7* %ptr0, i64 %i.08
> > -  %v0 = load i7, i7* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i7, i7* %ptr1, i64 %i.08
> > -  %v1 = load i7, i7* %arrayidx1
> > -  %cmp3 = icmp ult i7 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @loads_of_not_multiple_of_a_byte(i9* %ptr0, i9* %ptr1) {
> > -; CHECK-LABEL: @loads_of_not_multiple_of_a_byte(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i9, i9* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i9, i9* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i9, i9* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i9, i9* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp ult i9 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i9, i9* %ptr0, i64 %i.08
> > -  %v0 = load i9, i9* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i9, i9* %ptr1, i64 %i.08
> > -  %v1 = load i9, i9* %arrayidx1
> > -  %cmp3 = icmp ult i9 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @loop_instruction_used_in_phi_node_outside_loop(i8* %ptr0, i8* %ptr1) {
> > -; CHECK-LABEL: @loop_instruction_used_in_phi_node_outside_loop(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ [[CMP3]], [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ %cmp3, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @loop_has_write(i8* %ptr0, i8* %ptr1, i32* %write) {
> > -; CHECK-LABEL: @loop_has_write(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    store i32 0, i32* [[WRITE:%.*]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  store i32 0, i32* %write
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -declare void @sink()
> > -define i1 @loop_has_call(i8* %ptr0, i8* %ptr1, i32* %load) {
> > -; CHECK-LABEL: @loop_has_call(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    tail call void @sink()
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  tail call void @sink()
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @loop_has_atomic_load(i8* %ptr0, i8* %ptr1, i32* %load) {
> > -; CHECK-LABEL: @loop_has_atomic_load(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_08:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_COND:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, i8* [[PTR0:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[ARRAYIDX]]
> > -; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i8, i8* [[PTR1:%.*]], i64 [[I_08]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[ARRAYIDX1]]
> > -; CHECK-NEXT:    [[CMP3:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_08]], 1
> > -; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_COND]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.cond:
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 8
> > -; CHECK-NEXT:    [[TMP:%.*]] = load atomic i32, i32* [[LOAD:%.*]] unordered, align 1
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_COND]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.08 = phi i64 [ 0, %entry ], [ %inc, %for.cond ]
> > -  %arrayidx = getelementptr inbounds i8, i8* %ptr0, i64 %i.08
> > -  %v0 = load i8, i8* %arrayidx
> > -  %arrayidx1 = getelementptr inbounds i8, i8* %ptr1, i64 %i.08
> > -  %v1 = load i8, i8* %arrayidx1
> > -  %cmp3 = icmp eq i8 %v0, %v1
> > -  %inc = add nuw nsw i64 %i.08, 1
> > -  br i1 %cmp3, label %for.cond, label %cleanup
> > -
> > -for.cond:
> > -  %cmp = icmp ult i64 %inc, 8
> > -  %tmp = load atomic i32, i32* %load unordered, align 1
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.cond ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @
> > diff erent_load_step(i8* %ptr) {
> > -; CHECK-LABEL: @
> > diff erent_load_step(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_015:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_014:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_013:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[INCDEC_PTR:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_013]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_014]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_015]], 1
> > -; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, i8* [[PTR0_013]], i64 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR1_014]], i64 2
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.015, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 2
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @step_is_variable(i8* %ptr, i64 %step) {
> > -; CHECK-LABEL: @step_is_variable(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_015:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_014:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_013:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[INCDEC_PTR:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_013]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_014]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_015]], [[STEP:%.*]]
> > -; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, i8* [[PTR0_013]], i64 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR1_014]], i64 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.015, %step
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 1
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @load_step_is_variable(i8* %ptr, i64 %step) {
> > -; CHECK-LABEL: @load_step_is_variable(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_015:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_014:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_013:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[INCDEC_PTR:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_013]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_014]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_015]], 1
> > -; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, i8* [[PTR0_013]], i64 [[STEP:%.*]]
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR1_014]], i64 [[STEP]]
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.015, 1
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 %step
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 %step
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @step_and_load_step_is_variable(i8* %ptr, i64 %step) {
> > -; CHECK-LABEL: @step_and_load_step_is_variable(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_015:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_014:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_013:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[INCDEC_PTR:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_013]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_014]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_015]], [[STEP:%.*]]
> > -; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, i8* [[PTR0_013]], i64 [[STEP]]
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR1_014]], i64 [[STEP]]
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.015 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.014 = phi i8* [ %add.ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %ptr0.013 = phi i8* [ %ptr, %entry ], [ %incdec.ptr, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.013
> > -  %v1 = load i8, i8* %ptr1.014
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.015, %step
> > -  %incdec.ptr = getelementptr inbounds i8, i8* %ptr0.013, i64 %step
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr1.014, i64 %step
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @load_step_not_affine(i8* %ptr) {
> > -; CHECK-LABEL: @load_step_not_affine(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_018:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_017:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR4:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_016:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_016]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_017]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_018]], 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR0_016]], i64 [[INC]]
> > -; CHECK-NEXT:    [[ADD_PTR4]] = getelementptr inbounds i8, i8* [[PTR1_017]], i64 [[INC]]
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.018 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.017 = phi i8* [ %add.ptr, %entry ], [ %add.ptr4, %for.inc ]
> > -  %ptr0.016 = phi i8* [ %ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.016
> > -  %v1 = load i8, i8* %ptr1.017
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.018, 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr0.016, i64 %inc
> > -  %add.ptr4 = getelementptr inbounds i8, i8* %ptr1.017, i64 %inc
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @no_overlap_between_loads(i8* %ptr) {
> > -; CHECK-LABEL: @no_overlap_between_loads(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_016:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_015:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR4:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_014:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8* [[PTR0_014]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8* [[PTR1_015]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_016]], 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR0_014]], i64 2
> > -; CHECK-NEXT:    [[ADD_PTR4]] = getelementptr inbounds i8, i8* [[PTR1_015]], i64 2
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.016 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.015 = phi i8* [ %add.ptr, %entry ], [ %add.ptr4, %for.inc ]
> > -  %ptr0.014 = phi i8* [ %ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %v0 = load i8, i8* %ptr0.014
> > -  %v1 = load i8, i8* %ptr1.015
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.016, 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr0.014, i64 2
> > -  %add.ptr4 = getelementptr inbounds i8, i8* %ptr1.015, i64 2
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @volatile_loads(i8* %ptr) {
> > -; CHECK-LABEL: @volatile_loads(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_016:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_015:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR4:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_014:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load volatile i8, i8* [[PTR0_014]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load volatile i8, i8* [[PTR1_015]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_016]], 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR0_014]], i64 1
> > -; CHECK-NEXT:    [[ADD_PTR4]] = getelementptr inbounds i8, i8* [[PTR1_015]], i64 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.016 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.015 = phi i8* [ %add.ptr, %entry ], [ %add.ptr4, %for.inc ]
> > -  %ptr0.014 = phi i8* [ %ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %v0 = load volatile i8, i8* %ptr0.014
> > -  %v1 = load volatile i8, i8* %ptr1.015
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.016, 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr0.014, i64 1
> > -  %add.ptr4 = getelementptr inbounds i8, i8* %ptr1.015, i64 1
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @atomic_loads(i8* %ptr) {
> > -; CHECK-LABEL: @atomic_loads(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_016:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_015:%.*]] = phi i8* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR4:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_014:%.*]] = phi i8* [ [[PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load atomic i8, i8* [[PTR0_014]] unordered, align 1
> > -; CHECK-NEXT:    [[V1:%.*]] = load atomic i8, i8* [[PTR1_015]] unordered, align 1
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_016]], 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8* [[PTR0_014]], i64 1
> > -; CHECK-NEXT:    [[ADD_PTR4]] = getelementptr inbounds i8, i8* [[PTR1_015]], i64 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.016 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.015 = phi i8* [ %add.ptr, %entry ], [ %add.ptr4, %for.inc ]
> > -  %ptr0.014 = phi i8* [ %ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %v0 = load atomic i8, i8* %ptr0.014 unordered, align 1
> > -  %v1 = load atomic i8, i8* %ptr1.015 unordered, align 1
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.016, 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8* %ptr0.014, i64 1
> > -  %add.ptr4 = getelementptr inbounds i8, i8* %ptr1.015, i64 1
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -define i1 @address_space(i8 addrspace(1)* %ptr) {
> > -; CHECK-LABEL: @address_space(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[ADD_PTR:%.*]] = getelementptr inbounds i8, i8 addrspace(1)* [[PTR:%.*]], i64 8
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_016:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ]
> > -; CHECK-NEXT:    [[PTR1_015:%.*]] = phi i8 addrspace(1)* [ [[ADD_PTR]], [[ENTRY]] ], [ [[ADD_PTR4:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[PTR0_014:%.*]] = phi i8 addrspace(1)* [ [[PTR]], [[ENTRY]] ], [ [[ADD_PTR3:%.*]], [[FOR_INC]] ]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i8, i8 addrspace(1)* [[PTR0_014]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i8, i8 addrspace(1)* [[PTR1_015]]
> > -; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i8 [[V0]], [[V1]]
> > -; CHECK-NEXT:    br i1 [[CMP2]], label [[FOR_INC]], label [[CLEANUP:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw nsw i64 [[I_016]], 1
> > -; CHECK-NEXT:    [[ADD_PTR3]] = getelementptr inbounds i8, i8 addrspace(1)* [[PTR0_014]], i64 1
> > -; CHECK-NEXT:    [[ADD_PTR4]] = getelementptr inbounds i8, i8 addrspace(1)* [[PTR1_015]], i64 1
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], 16
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %add.ptr = getelementptr inbounds i8, i8 addrspace(1)* %ptr, i64 8
> > -  br label %for.body
> > -
> > -for.body:
> > -  %i.016 = phi i64 [ 0, %entry ], [ %inc, %for.inc ]
> > -  %ptr1.015 = phi i8 addrspace(1)* [ %add.ptr, %entry ], [ %add.ptr4, %for.inc ]
> > -  %ptr0.014 = phi i8 addrspace(1)* [ %ptr, %entry ], [ %add.ptr3, %for.inc ]
> > -  %v0 = load i8, i8 addrspace(1)* %ptr0.014
> > -  %v1 = load i8, i8 addrspace(1)* %ptr1.015
> > -  %cmp2 = icmp eq i8 %v0, %v1
> > -  br i1 %cmp2, label %for.inc, label %cleanup
> > -
> > -for.inc:
> > -  %inc = add nuw nsw i64 %i.016, 1
> > -  %add.ptr3 = getelementptr inbounds i8, i8 addrspace(1)* %ptr0.014, i64 1
> > -  %add.ptr4 = getelementptr inbounds i8, i8 addrspace(1)* %ptr1.015, i64 1
> > -  %cmp = icmp ult i64 %inc, 16
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:
> > -  %res = phi i1 [ false, %for.body ], [ true, %for.inc ]
> > -  ret i1 %res
> > -}
> > -
> > -; See https://bugs.llvm.org/show_bug.cgi?id=43206 for original reduced (but runnable) test:
> > -;
> > -; bool do_check(int i_max, int j_max, int**bptr, int* fillch) {
> > -;   for (int i = 0; i < i_max; i++)
> > -;       for (int j = 0; j < j_max; j++)
> > -;         if (bptr[i][j] != fillch[i])
> > -;           return 1;
> > -;   return 0;
> > -; }
> > -; The loads proceed
> > diff erently here - fillch[i] changes once per outer loop,
> > -; while bptr[i][j] changes both in inner loop, and in outer loop.
> > -define i1 @pr43206_
> > diff erent_loops(i32 %i_max, i32 %j_max, i32** %bptr, i32* %fillch) {
> > -; CHECK-LABEL: @pr43206_
> > diff erent_loops(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP31:%.*]] = icmp sgt i32 [[I_MAX:%.*]], 0
> > -; CHECK-NEXT:    [[CMP229:%.*]] = icmp sgt i32 [[J_MAX:%.*]], 0
> > -; CHECK-NEXT:    [[OR_COND:%.*]] = and i1 [[CMP31]], [[CMP229]]
> > -; CHECK-NEXT:    br i1 [[OR_COND]], label [[FOR_COND1_PREHEADER_US_PREHEADER:%.*]], label [[CLEANUP12:%.*]]
> > -; CHECK:       for.cond1.preheader.us.preheader:
> > -; CHECK-NEXT:    [[WIDE_TRIP_COUNT38:%.*]] = zext i32 [[I_MAX]] to i64
> > -; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[J_MAX]] to i64
> > -; CHECK-NEXT:    br label [[FOR_COND1_PREHEADER_US:%.*]]
> > -; CHECK:       for.cond1.preheader.us:
> > -; CHECK-NEXT:    [[INDVARS_IV36:%.*]] = phi i64 [ 0, [[FOR_COND1_PREHEADER_US_PREHEADER]] ], [ [[INDVARS_IV_NEXT37:%.*]], [[FOR_COND1_FOR_INC10_CRIT_EDGE_US:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX_US:%.*]] = getelementptr inbounds i32*, i32** [[BPTR:%.*]], i64 [[INDVARS_IV36]]
> > -; CHECK-NEXT:    [[V0:%.*]] = load i32*, i32** [[ARRAYIDX_US]], align 8
> > -; CHECK-NEXT:    [[ARRAYIDX8_US:%.*]] = getelementptr inbounds i32, i32* [[FILLCH:%.*]], i64 [[INDVARS_IV36]]
> > -; CHECK-NEXT:    [[V1:%.*]] = load i32, i32* [[ARRAYIDX8_US]], align 4
> > -; CHECK-NEXT:    br label [[FOR_BODY4_US:%.*]]
> > -; CHECK:       for.cond1.us:
> > -; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT:%.*]], [[WIDE_TRIP_COUNT]]
> > -; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_COND1_FOR_INC10_CRIT_EDGE_US]], label [[FOR_BODY4_US]]
> > -; CHECK:       for.body4.us:
> > -; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ 0, [[FOR_COND1_PREHEADER_US]] ], [ [[INDVARS_IV_NEXT]], [[FOR_COND1_US:%.*]] ]
> > -; CHECK-NEXT:    [[ARRAYIDX6_US:%.*]] = getelementptr inbounds i32, i32* [[V0]], i64 [[INDVARS_IV]]
> > -; CHECK-NEXT:    [[V2:%.*]] = load i32, i32* [[ARRAYIDX6_US]], align 4
> > -; CHECK-NEXT:    [[CMP9_US:%.*]] = icmp eq i32 [[V2]], [[V1]]
> > -; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
> > -; CHECK-NEXT:    br i1 [[CMP9_US]], label [[FOR_COND1_US]], label [[CLEANUP12_LOOPEXIT:%.*]]
> > -; CHECK:       for.cond1.for.inc10_crit_edge.us:
> > -; CHECK-NEXT:    [[INDVARS_IV_NEXT37]] = add nuw nsw i64 [[INDVARS_IV36]], 1
> > -; CHECK-NEXT:    [[EXITCOND39:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT37]], [[WIDE_TRIP_COUNT38]]
> > -; CHECK-NEXT:    br i1 [[EXITCOND39]], label [[CLEANUP12_LOOPEXIT1:%.*]], label [[FOR_COND1_PREHEADER_US]]
> > -; CHECK:       cleanup12.loopexit:
> > -; CHECK-NEXT:    br label [[CLEANUP12]]
> > -; CHECK:       cleanup12.loopexit1:
> > -; CHECK-NEXT:    br label [[CLEANUP12]]
> > -; CHECK:       cleanup12:
> > -; CHECK-NEXT:    [[V3:%.*]] = phi i1 [ false, [[ENTRY:%.*]] ], [ true, [[CLEANUP12_LOOPEXIT]] ], [ false, [[CLEANUP12_LOOPEXIT1]] ]
> > -; CHECK-NEXT:    ret i1 [[V3]]
> > -;
> > -entry:
> > -  %cmp31 = icmp sgt i32 %i_max, 0
> > -  %cmp229 = icmp sgt i32 %j_max, 0
> > -  %or.cond = and i1 %cmp31, %cmp229
> > -  br i1 %or.cond, label %for.cond1.preheader.us.preheader, label %cleanup12
> > -
> > -for.cond1.preheader.us.preheader:                 ; preds = %entry
> > -  %wide.trip.count38 = zext i32 %i_max to i64
> > -  %wide.trip.count = zext i32 %j_max to i64
> > -  br label %for.cond1.preheader.us
> > -
> > -for.cond1.preheader.us:                           ; preds = %for.cond1.for.inc10_crit_edge.us, %for.cond1.preheader.us.preheader
> > -  %indvars.iv36 = phi i64 [ 0, %for.cond1.preheader.us.preheader ], [ %indvars.iv.next37, %for.cond1.for.inc10_crit_edge.us ]
> > -  %arrayidx.us = getelementptr inbounds i32*, i32** %bptr, i64 %indvars.iv36
> > -  %v0 = load i32*, i32** %arrayidx.us, align 8
> > -  %arrayidx8.us = getelementptr inbounds i32, i32* %fillch, i64 %indvars.iv36
> > -  %v1 = load i32, i32* %arrayidx8.us, align 4
> > -  br label %for.body4.us
> > -
> > -for.cond1.us:                                     ; preds = %for.body4.us
> > -  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count
> > -  br i1 %exitcond, label %for.cond1.for.inc10_crit_edge.us, label %for.body4.us
> > -
> > -for.body4.us:                                     ; preds = %for.cond1.us, %for.cond1.preheader.us
> > -  %indvars.iv = phi i64 [ 0, %for.cond1.preheader.us ], [ %indvars.iv.next, %for.cond1.us ]
> > -  %arrayidx6.us = getelementptr inbounds i32, i32* %v0, i64 %indvars.iv
> > -  %v2 = load i32, i32* %arrayidx6.us, align 4
> > -  %cmp9.us = icmp eq i32 %v2, %v1
> > -  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
> > -  br i1 %cmp9.us, label %for.cond1.us, label %cleanup12
> > -
> > -for.cond1.for.inc10_crit_edge.us:                 ; preds = %for.cond1.us
> > -  %indvars.iv.next37 = add nuw nsw i64 %indvars.iv36, 1
> > -  %exitcond39 = icmp eq i64 %indvars.iv.next37, %wide.trip.count38
> > -  br i1 %exitcond39, label %cleanup12, label %for.cond1.preheader.us
> > -
> > -cleanup12:                                        ; preds = %for.cond1.for.inc10_crit_edge.us, %for.body4.us, %entry
> > -  %v3 = phi i1 [ false, %entry ], [ true, %for.body4.us ], [ false, %for.cond1.for.inc10_crit_edge.us ]
> > -  ret i1 %v3
> > -}
> > -
> > -; From https://bugs.llvm.org/show_bug.cgi?id=43687
> > -define void @body_always_branches_to_latch(i16* %a, i16* %b, i32) {
> > -; CHECK-LABEL: @body_always_branches_to_latch(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    br label [[BODY:%.*]]
> > -; CHECK:       body:
> > -; CHECK-NEXT:    [[A_DATA:%.*]] = load i16, i16* [[A:%.*]]
> > -; CHECK-NEXT:    [[B_DATA:%.*]] = load i16, i16* [[B:%.*]]
> > -; CHECK-NEXT:    [[COMPARED_EQUAL:%.*]] = icmp eq i16 [[A_DATA]], [[B_DATA]]
> > -; CHECK-NEXT:    br i1 [[COMPARED_EQUAL]], label [[LATCH:%.*]], label [[LATCH]]
> > -; CHECK:       latch:
> > -; CHECK-NEXT:    [[SHOULD_CONTINUE:%.*]] = icmp slt i32 undef, 79
> > -; CHECK-NEXT:    br i1 [[SHOULD_CONTINUE]], label [[BODY]], label [[END:%.*]]
> > -; CHECK:       end:
> > -; CHECK-NEXT:    ret void
> > -;
> > -entry:
> > -  br label %body
> > -
> > -body:                                   ; preds = %latch, %for.end1317
> > -  %a_data = load i16, i16* %a
> > -  %b_data = load i16, i16* %b
> > -  %compared_equal = icmp eq i16 %a_data, %b_data
> > -  br i1 %compared_equal, label %latch, label %latch
> > -
> > -latch:                                    ; preds = %body, %body
> > -  %should_continue = icmp slt i32 undef, 79
> > -  br i1 %should_continue, label %body, label %end
> > -
> > -end:                                    ; preds = %latch
> > -  ret void
> > -}
> >
> > diff  --git a/llvm/test/Transforms/LoopIdiom/bcmp-widening.ll b/llvm/test/Transforms/LoopIdiom/bcmp-widening.ll
> > deleted file mode 100644
> > index 4c8b7f3f0303..000000000000
> > --- a/llvm/test/Transforms/LoopIdiom/bcmp-widening.ll
> > +++ /dev/null
> > @@ -1,137 +0,0 @@
> > -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
> > -; RUN: opt -loop-idiom -verify -verify-each -verify-dom-info -verify-loop-info < %s -S | FileCheck %s
> > -
> > -target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
> > -
> > -; We do not necessarily have a loop with comparison of two loaded values.
> > -; The loop may already be doing bcmp() itself. We just need to widen it.
> > -
> > -; FIXME: -memcpyopt does not promote memcmp() source into memcmp() / bcmp().
> > -
> > -; #include <algorithm>
> > -;
> > -; // FIXME
> > -; bool widening_of_bcmp(char const* ptr0, char const* ptr1, size_t count) {
> > -;   static constexpr auto Size = 32, Step = 32;
> > -;   for(size_t i = 0; i < count; i++, ptr0 += Step, ptr1 += Step) {
> > -;     if(bcmp(ptr0, ptr1, Size) != 0)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -;
> > -; // FIXME
> > -; bool widening_of_overlapping_bcmp(char const* ptr0, char const* ptr1, size_t count) {
> > -;   static constexpr auto Size = 32, Step = 16;
> > -;   for(size_t i = 0; i < count; i++, ptr0 += Step, ptr1 += Step) {
> > -;     if(bcmp(ptr0, ptr1, Size) != 0)
> > -;       return false;
> > -;   }
> > -;   return true;
> > -; }
> > -
> > -declare i32 @bcmp(i8*, i8*, i64)
> > -
> > -; FIXME
> > -define i1 @_Z18widening_of_bcmpPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z18widening_of_bcmpPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP7:%.*]] = icmp eq i64 [[COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP7]], label [[CLEANUP:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_010:%.*]] = phi i64 [ [[INC:%.*]], [[FOR_INC:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[PTR1_ADDR_09:%.*]] = phi i8* [ [[ADD_PTR2:%.*]], [[FOR_INC]] ], [ [[PTR1:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[PTR0_ADDR_08:%.*]] = phi i8* [ [[ADD_PTR:%.*]], [[FOR_INC]] ], [ [[PTR0:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[BCMP:%.*]] = tail call i32 @bcmp(i8* [[PTR0_ADDR_08]], i8* [[PTR1_ADDR_09]], i64 32)
> > -; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[BCMP]], 0
> > -; CHECK-NEXT:    br i1 [[CMP1]], label [[FOR_INC]], label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_010]], 1
> > -; CHECK-NEXT:    [[ADD_PTR]] = getelementptr inbounds i8, i8* [[PTR0_ADDR_08]], i64 32
> > -; CHECK-NEXT:    [[ADD_PTR2]] = getelementptr inbounds i8, i8* [[PTR1_ADDR_09]], i64 32
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], [[COUNT]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp7 = icmp eq i64 %count, 0
> > -  br i1 %cmp7, label %cleanup, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.010 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.09 = phi i8* [ %add.ptr2, %for.inc ], [ %ptr1, %entry ]
> > -  %ptr0.addr.08 = phi i8* [ %add.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %bcmp = tail call i32 @bcmp(i8* %ptr0.addr.08, i8* %ptr1.addr.09, i64 32)
> > -  %cmp1 = icmp eq i32 %bcmp, 0
> > -  br i1 %cmp1, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.010, 1
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0.addr.08, i64 32
> > -  %add.ptr2 = getelementptr inbounds i8, i8* %ptr1.addr.09, i64 32
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> > -
> > -; FIXME
> > -define i1 @_Z30widening_of_overlapping_bcmpPKcS0_m(i8* %ptr0, i8* %ptr1, i64 %count) {
> > -; CHECK-LABEL: @_Z30widening_of_overlapping_bcmpPKcS0_m(
> > -; CHECK-NEXT:  entry:
> > -; CHECK-NEXT:    [[CMP7:%.*]] = icmp eq i64 [[COUNT:%.*]], 0
> > -; CHECK-NEXT:    br i1 [[CMP7]], label [[CLEANUP:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
> > -; CHECK:       for.body.preheader:
> > -; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
> > -; CHECK:       for.body:
> > -; CHECK-NEXT:    [[I_010:%.*]] = phi i64 [ [[INC:%.*]], [[FOR_INC:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[PTR1_ADDR_09:%.*]] = phi i8* [ [[ADD_PTR2:%.*]], [[FOR_INC]] ], [ [[PTR1:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[PTR0_ADDR_08:%.*]] = phi i8* [ [[ADD_PTR:%.*]], [[FOR_INC]] ], [ [[PTR0:%.*]], [[FOR_BODY_PREHEADER]] ]
> > -; CHECK-NEXT:    [[BCMP:%.*]] = tail call i32 @bcmp(i8* [[PTR0_ADDR_08]], i8* [[PTR1_ADDR_09]], i64 32)
> > -; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[BCMP]], 0
> > -; CHECK-NEXT:    br i1 [[CMP1]], label [[FOR_INC]], label [[CLEANUP_LOOPEXIT:%.*]]
> > -; CHECK:       for.inc:
> > -; CHECK-NEXT:    [[INC]] = add nuw i64 [[I_010]], 1
> > -; CHECK-NEXT:    [[ADD_PTR]] = getelementptr inbounds i8, i8* [[PTR0_ADDR_08]], i64 16
> > -; CHECK-NEXT:    [[ADD_PTR2]] = getelementptr inbounds i8, i8* [[PTR1_ADDR_09]], i64 16
> > -; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[INC]], [[COUNT]]
> > -; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[CLEANUP_LOOPEXIT]]
> > -; CHECK:       cleanup.loopexit:
> > -; CHECK-NEXT:    [[RES_PH:%.*]] = phi i1 [ false, [[FOR_BODY]] ], [ true, [[FOR_INC]] ]
> > -; CHECK-NEXT:    br label [[CLEANUP]]
> > -; CHECK:       cleanup:
> > -; CHECK-NEXT:    [[RES:%.*]] = phi i1 [ true, [[ENTRY:%.*]] ], [ [[RES_PH]], [[CLEANUP_LOOPEXIT]] ]
> > -; CHECK-NEXT:    ret i1 [[RES]]
> > -;
> > -entry:
> > -  %cmp7 = icmp eq i64 %count, 0
> > -  br i1 %cmp7, label %cleanup, label %for.body
> > -
> > -for.body:                                         ; preds = %entry, %for.inc
> > -  %i.010 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
> > -  %ptr1.addr.09 = phi i8* [ %add.ptr2, %for.inc ], [ %ptr1, %entry ]
> > -  %ptr0.addr.08 = phi i8* [ %add.ptr, %for.inc ], [ %ptr0, %entry ]
> > -  %bcmp = tail call i32 @bcmp(i8* %ptr0.addr.08, i8* %ptr1.addr.09, i64 32)
> > -  %cmp1 = icmp eq i32 %bcmp, 0
> > -  br i1 %cmp1, label %for.inc, label %cleanup
> > -
> > -for.inc:                                          ; preds = %for.body
> > -  %inc = add nuw i64 %i.010, 1
> > -  %add.ptr = getelementptr inbounds i8, i8* %ptr0.addr.08, i64 16
> > -  %add.ptr2 = getelementptr inbounds i8, i8* %ptr1.addr.09, i64 16
> > -  %cmp = icmp ult i64 %inc, %count
> > -  br i1 %cmp, label %for.body, label %cleanup
> > -
> > -cleanup:                                          ; preds = %for.body, %for.inc, %entry
> > -  %res = phi i1 [ true, %entry ], [ true, %for.inc ], [ false, %for.body ]
> > -  ret i1 %res
> > -}
> >
> >
> >
> > _______________________________________________
> > llvm-commits mailing list
> > llvm-commits at lists.llvm.org
> > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits


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