Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 5432 deletions

diff --git a/gnu/llvm/lib/Analysis/ValueTracking.cpp b/gnu/llvm/lib/Analysis/ValueTracking.cpp
deleted file mode 100644
index 0446426c0e6..00000000000
--- a/gnu/llvm/lib/Analysis/ValueTracking.cpp
+++ /dev/null
@@ -1,5432 +0,0 @@
-//===- ValueTracking.cpp - Walk computations to compute properties --------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file contains routines that help analyze properties that chains of
-// computations have.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/ADT/APFloat.h"
-#include "llvm/ADT/APInt.h"
-#include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/None.h"
-#include "llvm/ADT/Optional.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/iterator_range.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/AssumptionCache.h"
-#include "llvm/Analysis/GuardUtils.h"
-#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Analysis/Loads.h"
-#include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/OptimizationRemarkEmitter.h"
-#include "llvm/Analysis/TargetLibraryInfo.h"
-#include "llvm/IR/Argument.h"
-#include "llvm/IR/Attributes.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/CallSite.h"
-#include "llvm/IR/Constant.h"
-#include "llvm/IR/ConstantRange.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/DiagnosticInfo.h"
-#include "llvm/IR/Dominators.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/GetElementPtrTypeIterator.h"
-#include "llvm/IR/GlobalAlias.h"
-#include "llvm/IR/GlobalValue.h"
-#include "llvm/IR/GlobalVariable.h"
-#include "llvm/IR/InstrTypes.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/IR/Intrinsics.h"
-#include "llvm/IR/LLVMContext.h"
-#include "llvm/IR/Metadata.h"
-#include "llvm/IR/Module.h"
-#include "llvm/IR/Operator.h"
-#include "llvm/IR/PatternMatch.h"
-#include "llvm/IR/Type.h"
-#include "llvm/IR/User.h"
-#include "llvm/IR/Value.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/KnownBits.h"
-#include "llvm/Support/MathExtras.h"
-#include <algorithm>
-#include <array>
-#include <cassert>
-#include <cstdint>
-#include <iterator>
-#include <utility>
-
-using namespace llvm;
-using namespace llvm::PatternMatch;
-
-const unsigned MaxDepth = 6;
-
-// Controls the number of uses of the value searched for possible
-// dominating comparisons.
-static cl::opt<unsigned> DomConditionsMaxUses("dom-conditions-max-uses",
-                                              cl::Hidden, cl::init(20));
-
-/// Returns the bitwidth of the given scalar or pointer type. For vector types,
-/// returns the element type's bitwidth.
-static unsigned getBitWidth(Type *Ty, const DataLayout &DL) {
-  if (unsigned BitWidth = Ty->getScalarSizeInBits())
-    return BitWidth;
-
-  return DL.getIndexTypeSizeInBits(Ty);
-}
-
-namespace {
-
-// Simplifying using an assume can only be done in a particular control-flow
-// context (the context instruction provides that context). If an assume and
-// the context instruction are not in the same block then the DT helps in
-// figuring out if we can use it.
-struct Query {
-  const DataLayout &DL;
-  AssumptionCache *AC;
-  const Instruction *CxtI;
-  const DominatorTree *DT;
-
-  // Unlike the other analyses, this may be a nullptr because not all clients
-  // provide it currently.
-  OptimizationRemarkEmitter *ORE;
-
-  /// Set of assumptions that should be excluded from further queries.
-  /// This is because of the potential for mutual recursion to cause
-  /// computeKnownBits to repeatedly visit the same assume intrinsic. The
-  /// classic case of this is assume(x = y), which will attempt to determine
-  /// bits in x from bits in y, which will attempt to determine bits in y from
-  /// bits in x, etc. Regarding the mutual recursion, computeKnownBits can call
-  /// isKnownNonZero, which calls computeKnownBits and isKnownToBeAPowerOfTwo
-  /// (all of which can call computeKnownBits), and so on.
-  std::array<const Value *, MaxDepth> Excluded;
-
-  /// If true, it is safe to use metadata during simplification.
-  InstrInfoQuery IIQ;
-
-  unsigned NumExcluded = 0;
-
-  Query(const DataLayout &DL, AssumptionCache *AC, const Instruction *CxtI,
-        const DominatorTree *DT, bool UseInstrInfo,
-        OptimizationRemarkEmitter *ORE = nullptr)
-      : DL(DL), AC(AC), CxtI(CxtI), DT(DT), ORE(ORE), IIQ(UseInstrInfo) {}
-
-  Query(const Query &Q, const Value *NewExcl)
-      : DL(Q.DL), AC(Q.AC), CxtI(Q.CxtI), DT(Q.DT), ORE(Q.ORE), IIQ(Q.IIQ),
-        NumExcluded(Q.NumExcluded) {
-    Excluded = Q.Excluded;
-    Excluded[NumExcluded++] = NewExcl;
-    assert(NumExcluded <= Excluded.size());
-  }
-
-  bool isExcluded(const Value *Value) const {
-    if (NumExcluded == 0)
-      return false;
-    auto End = Excluded.begin() + NumExcluded;
-    return std::find(Excluded.begin(), End, Value) != End;
-  }
-};
-
-} // end anonymous namespace
-
-// Given the provided Value and, potentially, a context instruction, return
-// the preferred context instruction (if any).
-static const Instruction *safeCxtI(const Value *V, const Instruction *CxtI) {
-  // If we've been provided with a context instruction, then use that (provided
-  // it has been inserted).
-  if (CxtI && CxtI->getParent())
-    return CxtI;
-
-  // If the value is really an already-inserted instruction, then use that.
-  CxtI = dyn_cast<Instruction>(V);
-  if (CxtI && CxtI->getParent())
-    return CxtI;
-
-  return nullptr;
-}
-
-static void computeKnownBits(const Value *V, KnownBits &Known,
-                             unsigned Depth, const Query &Q);
-
-void llvm::computeKnownBits(const Value *V, KnownBits &Known,
-                            const DataLayout &DL, unsigned Depth,
-                            AssumptionCache *AC, const Instruction *CxtI,
-                            const DominatorTree *DT,
-                            OptimizationRemarkEmitter *ORE, bool UseInstrInfo) {
-  ::computeKnownBits(V, Known, Depth,
-                     Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE));
-}
-
-static KnownBits computeKnownBits(const Value *V, unsigned Depth,
-                                  const Query &Q);
-
-KnownBits llvm::computeKnownBits(const Value *V, const DataLayout &DL,
-                                 unsigned Depth, AssumptionCache *AC,
-                                 const Instruction *CxtI,
-                                 const DominatorTree *DT,
-                                 OptimizationRemarkEmitter *ORE,
-                                 bool UseInstrInfo) {
-  return ::computeKnownBits(
-      V, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE));
-}
-
-bool llvm::haveNoCommonBitsSet(const Value *LHS, const Value *RHS,
-                               const DataLayout &DL, AssumptionCache *AC,
-                               const Instruction *CxtI, const DominatorTree *DT,
-                               bool UseInstrInfo) {
-  assert(LHS->getType() == RHS->getType() &&
-         "LHS and RHS should have the same type");
-  assert(LHS->getType()->isIntOrIntVectorTy() &&
-         "LHS and RHS should be integers");
-  // Look for an inverted mask: (X & ~M) op (Y & M).
-  Value *M;
-  if (match(LHS, m_c_And(m_Not(m_Value(M)), m_Value())) &&
-      match(RHS, m_c_And(m_Specific(M), m_Value())))
-    return true;
-  if (match(RHS, m_c_And(m_Not(m_Value(M)), m_Value())) &&
-      match(LHS, m_c_And(m_Specific(M), m_Value())))
-    return true;
-  IntegerType *IT = cast<IntegerType>(LHS->getType()->getScalarType());
-  KnownBits LHSKnown(IT->getBitWidth());
-  KnownBits RHSKnown(IT->getBitWidth());
-  computeKnownBits(LHS, LHSKnown, DL, 0, AC, CxtI, DT, nullptr, UseInstrInfo);
-  computeKnownBits(RHS, RHSKnown, DL, 0, AC, CxtI, DT, nullptr, UseInstrInfo);
-  return (LHSKnown.Zero | RHSKnown.Zero).isAllOnesValue();
-}
-
-bool llvm::isOnlyUsedInZeroEqualityComparison(const Instruction *CxtI) {
-  for (const User *U : CxtI->users()) {
-    if (const ICmpInst *IC = dyn_cast<ICmpInst>(U))
-      if (IC->isEquality())
-        if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
-          if (C->isNullValue())
-            continue;
-    return false;
-  }
-  return true;
-}
-
-static bool isKnownToBeAPowerOfTwo(const Value *V, bool OrZero, unsigned Depth,
-                                   const Query &Q);
-
-bool llvm::isKnownToBeAPowerOfTwo(const Value *V, const DataLayout &DL,
-                                  bool OrZero, unsigned Depth,
-                                  AssumptionCache *AC, const Instruction *CxtI,
-                                  const DominatorTree *DT, bool UseInstrInfo) {
-  return ::isKnownToBeAPowerOfTwo(
-      V, OrZero, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo));
-}
-
-static bool isKnownNonZero(const Value *V, unsigned Depth, const Query &Q);
-
-bool llvm::isKnownNonZero(const Value *V, const DataLayout &DL, unsigned Depth,
-                          AssumptionCache *AC, const Instruction *CxtI,
-                          const DominatorTree *DT, bool UseInstrInfo) {
-  return ::isKnownNonZero(V, Depth,
-                          Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo));
-}
-
-bool llvm::isKnownNonNegative(const Value *V, const DataLayout &DL,
-                              unsigned Depth, AssumptionCache *AC,
-                              const Instruction *CxtI, const DominatorTree *DT,
-                              bool UseInstrInfo) {
-  KnownBits Known =
-      computeKnownBits(V, DL, Depth, AC, CxtI, DT, nullptr, UseInstrInfo);
-  return Known.isNonNegative();
-}
-
-bool llvm::isKnownPositive(const Value *V, const DataLayout &DL, unsigned Depth,
-                           AssumptionCache *AC, const Instruction *CxtI,
-                           const DominatorTree *DT, bool UseInstrInfo) {
-  if (auto *CI = dyn_cast<ConstantInt>(V))
-    return CI->getValue().isStrictlyPositive();
-
-  // TODO: We'd doing two recursive queries here.  We should factor this such
-  // that only a single query is needed.
-  return isKnownNonNegative(V, DL, Depth, AC, CxtI, DT, UseInstrInfo) &&
-         isKnownNonZero(V, DL, Depth, AC, CxtI, DT, UseInstrInfo);
-}
-
-bool llvm::isKnownNegative(const Value *V, const DataLayout &DL, unsigned Depth,
-                           AssumptionCache *AC, const Instruction *CxtI,
-                           const DominatorTree *DT, bool UseInstrInfo) {
-  KnownBits Known =
-      computeKnownBits(V, DL, Depth, AC, CxtI, DT, nullptr, UseInstrInfo);
-  return Known.isNegative();
-}
-
-static bool isKnownNonEqual(const Value *V1, const Value *V2, const Query &Q);
-
-bool llvm::isKnownNonEqual(const Value *V1, const Value *V2,
-                           const DataLayout &DL, AssumptionCache *AC,
-                           const Instruction *CxtI, const DominatorTree *DT,
-                           bool UseInstrInfo) {
-  return ::isKnownNonEqual(V1, V2,
-                           Query(DL, AC, safeCxtI(V1, safeCxtI(V2, CxtI)), DT,
-                                 UseInstrInfo, /*ORE=*/nullptr));
-}
-
-static bool MaskedValueIsZero(const Value *V, const APInt &Mask, unsigned Depth,
-                              const Query &Q);
-
-bool llvm::MaskedValueIsZero(const Value *V, const APInt &Mask,
-                             const DataLayout &DL, unsigned Depth,
-                             AssumptionCache *AC, const Instruction *CxtI,
-                             const DominatorTree *DT, bool UseInstrInfo) {
-  return ::MaskedValueIsZero(
-      V, Mask, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo));
-}
-
-static unsigned ComputeNumSignBits(const Value *V, unsigned Depth,
-                                   const Query &Q);
-
-unsigned llvm::ComputeNumSignBits(const Value *V, const DataLayout &DL,
-                                  unsigned Depth, AssumptionCache *AC,
-                                  const Instruction *CxtI,
-                                  const DominatorTree *DT, bool UseInstrInfo) {
-  return ::ComputeNumSignBits(
-      V, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo));
-}
-
-static void computeKnownBitsAddSub(bool Add, const Value *Op0, const Value *Op1,
-                                   bool NSW,
-                                   KnownBits &KnownOut, KnownBits &Known2,
-                                   unsigned Depth, const Query &Q) {
-  unsigned BitWidth = KnownOut.getBitWidth();
-
-  // If an initial sequence of bits in the result is not needed, the
-  // corresponding bits in the operands are not needed.
-  KnownBits LHSKnown(BitWidth);
-  computeKnownBits(Op0, LHSKnown, Depth + 1, Q);
-  computeKnownBits(Op1, Known2, Depth + 1, Q);
-
-  KnownOut = KnownBits::computeForAddSub(Add, NSW, LHSKnown, Known2);
-}
-
-static void computeKnownBitsMul(const Value *Op0, const Value *Op1, bool NSW,
-                                KnownBits &Known, KnownBits &Known2,
-                                unsigned Depth, const Query &Q) {
-  unsigned BitWidth = Known.getBitWidth();
-  computeKnownBits(Op1, Known, Depth + 1, Q);
-  computeKnownBits(Op0, Known2, Depth + 1, Q);
-
-  bool isKnownNegative = false;
-  bool isKnownNonNegative = false;
-  // If the multiplication is known not to overflow, compute the sign bit.
-  if (NSW) {
-    if (Op0 == Op1) {
-      // The product of a number with itself is non-negative.
-      isKnownNonNegative = true;
-    } else {
-      bool isKnownNonNegativeOp1 = Known.isNonNegative();
-      bool isKnownNonNegativeOp0 = Known2.isNonNegative();
-      bool isKnownNegativeOp1 = Known.isNegative();
-      bool isKnownNegativeOp0 = Known2.isNegative();
-      // The product of two numbers with the same sign is non-negative.
-      isKnownNonNegative = (isKnownNegativeOp1 && isKnownNegativeOp0) ||
-        (isKnownNonNegativeOp1 && isKnownNonNegativeOp0);
-      // The product of a negative number and a non-negative number is either
-      // negative or zero.
-      if (!isKnownNonNegative)
-        isKnownNegative = (isKnownNegativeOp1 && isKnownNonNegativeOp0 &&
-                           isKnownNonZero(Op0, Depth, Q)) ||
-                          (isKnownNegativeOp0 && isKnownNonNegativeOp1 &&
-                           isKnownNonZero(Op1, Depth, Q));
-    }
-  }
-
-  assert(!Known.hasConflict() && !Known2.hasConflict());
-  // Compute a conservative estimate for high known-0 bits.
-  unsigned LeadZ =  std::max(Known.countMinLeadingZeros() +
-                             Known2.countMinLeadingZeros(),
-                             BitWidth) - BitWidth;
-  LeadZ = std::min(LeadZ, BitWidth);
-
-  // The result of the bottom bits of an integer multiply can be
-  // inferred by looking at the bottom bits of both operands and
-  // multiplying them together.
-  // We can infer at least the minimum number of known trailing bits
-  // of both operands. Depending on number of trailing zeros, we can
-  // infer more bits, because (a*b) <=> ((a/m) * (b/n)) * (m*n) assuming
-  // a and b are divisible by m and n respectively.
-  // We then calculate how many of those bits are inferrable and set
-  // the output. For example, the i8 mul:
-  //  a = XXXX1100 (12)
-  //  b = XXXX1110 (14)
-  // We know the bottom 3 bits are zero since the first can be divided by
-  // 4 and the second by 2, thus having ((12/4) * (14/2)) * (2*4).
-  // Applying the multiplication to the trimmed arguments gets:
-  //    XX11 (3)
-  //    X111 (7)
-  // -------
-  //    XX11
-  //   XX11
-  //  XX11
-  // XX11
-  // -------
-  // XXXXX01
-  // Which allows us to infer the 2 LSBs. Since we're multiplying the result
-  // by 8, the bottom 3 bits will be 0, so we can infer a total of 5 bits.
-  // The proof for this can be described as:
-  // Pre: (C1 >= 0) && (C1 < (1 << C5)) && (C2 >= 0) && (C2 < (1 << C6)) &&
-  //      (C7 == (1 << (umin(countTrailingZeros(C1), C5) +
-  //                    umin(countTrailingZeros(C2), C6) +
-  //                    umin(C5 - umin(countTrailingZeros(C1), C5),
-  //                         C6 - umin(countTrailingZeros(C2), C6)))) - 1)
-  // %aa = shl i8 %a, C5
-  // %bb = shl i8 %b, C6
-  // %aaa = or i8 %aa, C1
-  // %bbb = or i8 %bb, C2
-  // %mul = mul i8 %aaa, %bbb
-  // %mask = and i8 %mul, C7
-  //   =>
-  // %mask = i8 ((C1*C2)&C7)
-  // Where C5, C6 describe the known bits of %a, %b
-  // C1, C2 describe the known bottom bits of %a, %b.
-  // C7 describes the mask of the known bits of the result.
-  APInt Bottom0 = Known.One;
-  APInt Bottom1 = Known2.One;
-
-  // How many times we'd be able to divide each argument by 2 (shr by 1).
-  // This gives us the number of trailing zeros on the multiplication result.
-  unsigned TrailBitsKnown0 = (Known.Zero | Known.One).countTrailingOnes();
-  unsigned TrailBitsKnown1 = (Known2.Zero | Known2.One).countTrailingOnes();
-  unsigned TrailZero0 = Known.countMinTrailingZeros();
-  unsigned TrailZero1 = Known2.countMinTrailingZeros();
-  unsigned TrailZ = TrailZero0 + TrailZero1;
-
-  // Figure out the fewest known-bits operand.
-  unsigned SmallestOperand = std::min(TrailBitsKnown0 - TrailZero0,
-                                      TrailBitsKnown1 - TrailZero1);
-  unsigned ResultBitsKnown = std::min(SmallestOperand + TrailZ, BitWidth);
-
-  APInt BottomKnown = Bottom0.getLoBits(TrailBitsKnown0) *
-                      Bottom1.getLoBits(TrailBitsKnown1);
-
-  Known.resetAll();
-  Known.Zero.setHighBits(LeadZ);
-  Known.Zero |= (~BottomKnown).getLoBits(ResultBitsKnown);
-  Known.One |= BottomKnown.getLoBits(ResultBitsKnown);
-
-  // Only make use of no-wrap flags if we failed to compute the sign bit
-  // directly.  This matters if the multiplication always overflows, in
-  // which case we prefer to follow the result of the direct computation,
-  // though as the program is invoking undefined behaviour we can choose
-  // whatever we like here.
-  if (isKnownNonNegative && !Known.isNegative())
-    Known.makeNonNegative();
-  else if (isKnownNegative && !Known.isNonNegative())
-    Known.makeNegative();
-}
-
-void llvm::computeKnownBitsFromRangeMetadata(const MDNode &Ranges,
-                                             KnownBits &Known) {
-  unsigned BitWidth = Known.getBitWidth();
-  unsigned NumRanges = Ranges.getNumOperands() / 2;
-  assert(NumRanges >= 1);
-
-  Known.Zero.setAllBits();
-  Known.One.setAllBits();
-
-  for (unsigned i = 0; i < NumRanges; ++i) {
-    ConstantInt *Lower =
-        mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0));
-    ConstantInt *Upper =
-        mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1));
-    ConstantRange Range(Lower->getValue(), Upper->getValue());
-
-    // The first CommonPrefixBits of all values in Range are equal.
-    unsigned CommonPrefixBits =
-        (Range.getUnsignedMax() ^ Range.getUnsignedMin()).countLeadingZeros();
-
-    APInt Mask = APInt::getHighBitsSet(BitWidth, CommonPrefixBits);
-    Known.One &= Range.getUnsignedMax() & Mask;
-    Known.Zero &= ~Range.getUnsignedMax() & Mask;
-  }
-}
-
-static bool isEphemeralValueOf(const Instruction *I, const Value *E) {
-  SmallVector<const Value *, 16> WorkSet(1, I);
-  SmallPtrSet<const Value *, 32> Visited;
-  SmallPtrSet<const Value *, 16> EphValues;
-
-  // The instruction defining an assumption's condition itself is always
-  // considered ephemeral to that assumption (even if it has other
-  // non-ephemeral users). See r246696's test case for an example.
-  if (is_contained(I->operands(), E))
-    return true;
-
-  while (!WorkSet.empty()) {
-    const Value *V = WorkSet.pop_back_val();
-    if (!Visited.insert(V).second)
-      continue;
-
-    // If all uses of this value are ephemeral, then so is this value.
-    if (llvm::all_of(V->users(), [&](const User *U) {
-                                   return EphValues.count(U);
-                                 })) {
-      if (V == E)
-        return true;
-
-      if (V == I || isSafeToSpeculativelyExecute(V)) {
-       EphValues.insert(V);
-       if (const User *U = dyn_cast<User>(V))
-         for (User::const_op_iterator J = U->op_begin(), JE = U->op_end();
-              J != JE; ++J)
-           WorkSet.push_back(*J);
-      }
-    }
-  }
-
-  return false;
-}
-
-// Is this an intrinsic that cannot be speculated but also cannot trap?
-bool llvm::isAssumeLikeIntrinsic(const Instruction *I) {
-  if (const CallInst *CI = dyn_cast<CallInst>(I))
-    if (Function *F = CI->getCalledFunction())
-      switch (F->getIntrinsicID()) {
-      default: break;
-      // FIXME: This list is repeated from NoTTI::getIntrinsicCost.
-      case Intrinsic::assume:
-      case Intrinsic::sideeffect:
-      case Intrinsic::dbg_declare:
-      case Intrinsic::dbg_value:
-      case Intrinsic::dbg_label:
-      case Intrinsic::invariant_start:
-      case Intrinsic::invariant_end:
-      case Intrinsic::lifetime_start:
-      case Intrinsic::lifetime_end:
-      case Intrinsic::objectsize:
-      case Intrinsic::ptr_annotation:
-      case Intrinsic::var_annotation:
-        return true;
-      }
-
-  return false;
-}
-
-bool llvm::isValidAssumeForContext(const Instruction *Inv,
-                                   const Instruction *CxtI,
-                                   const DominatorTree *DT) {
-  // There are two restrictions on the use of an assume:
-  //  1. The assume must dominate the context (or the control flow must
-  //     reach the assume whenever it reaches the context).
-  //  2. The context must not be in the assume's set of ephemeral values
-  //     (otherwise we will use the assume to prove that the condition
-  //     feeding the assume is trivially true, thus causing the removal of
-  //     the assume).
-
-  if (DT) {
-    if (DT->dominates(Inv, CxtI))
-      return true;
-  } else if (Inv->getParent() == CxtI->getParent()->getSinglePredecessor()) {
-    // We don't have a DT, but this trivially dominates.
-    return true;
-  }
-
-  // With or without a DT, the only remaining case we will check is if the
-  // instructions are in the same BB.  Give up if that is not the case.
-  if (Inv->getParent() != CxtI->getParent())
-    return false;
-
-  // If we have a dom tree, then we now know that the assume doesn't dominate
-  // the other instruction.  If we don't have a dom tree then we can check if
-  // the assume is first in the BB.
-  if (!DT) {
-    // Search forward from the assume until we reach the context (or the end
-    // of the block); the common case is that the assume will come first.
-    for (auto I = std::next(BasicBlock::const_iterator(Inv)),
-         IE = Inv->getParent()->end(); I != IE; ++I)
-      if (&*I == CxtI)
-        return true;
-  }
-
-  // The context comes first, but they're both in the same block. Make sure
-  // there is nothing in between that might interrupt the control flow.
-  for (BasicBlock::const_iterator I =
-         std::next(BasicBlock::const_iterator(CxtI)), IE(Inv);
-       I != IE; ++I)
-    if (!isSafeToSpeculativelyExecute(&*I) && !isAssumeLikeIntrinsic(&*I))
-      return false;
-
-  return !isEphemeralValueOf(Inv, CxtI);
-}
-
-static void computeKnownBitsFromAssume(const Value *V, KnownBits &Known,
-                                       unsigned Depth, const Query &Q) {
-  // Use of assumptions is context-sensitive. If we don't have a context, we
-  // cannot use them!
-  if (!Q.AC || !Q.CxtI)
-    return;
-
-  unsigned BitWidth = Known.getBitWidth();
-
-  // Note that the patterns below need to be kept in sync with the code
-  // in AssumptionCache::updateAffectedValues.
-
-  for (auto &AssumeVH : Q.AC->assumptionsFor(V)) {
-    if (!AssumeVH)
-      continue;
-    CallInst *I = cast<CallInst>(AssumeVH);
-    assert(I->getParent()->getParent() == Q.CxtI->getParent()->getParent() &&
-           "Got assumption for the wrong function!");
-    if (Q.isExcluded(I))
-      continue;
-
-    // Warning: This loop can end up being somewhat performance sensitive.
-    // We're running this loop for once for each value queried resulting in a
-    // runtime of ~O(#assumes * #values).
-
-    assert(I->getCalledFunction()->getIntrinsicID() == Intrinsic::assume &&
-           "must be an assume intrinsic");
-
-    Value *Arg = I->getArgOperand(0);
-
-    if (Arg == V && isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      assert(BitWidth == 1 && "assume operand is not i1?");
-      Known.setAllOnes();
-      return;
-    }
-    if (match(Arg, m_Not(m_Specific(V))) &&
-        isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      assert(BitWidth == 1 && "assume operand is not i1?");
-      Known.setAllZero();
-      return;
-    }
-
-    // The remaining tests are all recursive, so bail out if we hit the limit.
-    if (Depth == MaxDepth)
-      continue;
-
-    Value *A, *B;
-    auto m_V = m_CombineOr(m_Specific(V),
-                           m_CombineOr(m_PtrToInt(m_Specific(V)),
-                           m_BitCast(m_Specific(V))));
-
-    CmpInst::Predicate Pred;
-    uint64_t C;
-    // assume(v = a)
-    if (match(Arg, m_c_ICmp(Pred, m_V, m_Value(A))) &&
-        Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      Known.Zero |= RHSKnown.Zero;
-      Known.One  |= RHSKnown.One;
-    // assume(v & b = a)
-    } else if (match(Arg,
-                     m_c_ICmp(Pred, m_c_And(m_V, m_Value(B)), m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits MaskKnown(BitWidth);
-      computeKnownBits(B, MaskKnown, Depth+1, Query(Q, I));
-
-      // For those bits in the mask that are known to be one, we can propagate
-      // known bits from the RHS to V.
-      Known.Zero |= RHSKnown.Zero & MaskKnown.One;
-      Known.One  |= RHSKnown.One  & MaskKnown.One;
-    // assume(~(v & b) = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Not(m_c_And(m_V, m_Value(B))),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits MaskKnown(BitWidth);
-      computeKnownBits(B, MaskKnown, Depth+1, Query(Q, I));
-
-      // For those bits in the mask that are known to be one, we can propagate
-      // inverted known bits from the RHS to V.
-      Known.Zero |= RHSKnown.One  & MaskKnown.One;
-      Known.One  |= RHSKnown.Zero & MaskKnown.One;
-    // assume(v | b = a)
-    } else if (match(Arg,
-                     m_c_ICmp(Pred, m_c_Or(m_V, m_Value(B)), m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits BKnown(BitWidth);
-      computeKnownBits(B, BKnown, Depth+1, Query(Q, I));
-
-      // For those bits in B that are known to be zero, we can propagate known
-      // bits from the RHS to V.
-      Known.Zero |= RHSKnown.Zero & BKnown.Zero;
-      Known.One  |= RHSKnown.One  & BKnown.Zero;
-    // assume(~(v | b) = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Not(m_c_Or(m_V, m_Value(B))),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits BKnown(BitWidth);
-      computeKnownBits(B, BKnown, Depth+1, Query(Q, I));
-
-      // For those bits in B that are known to be zero, we can propagate
-      // inverted known bits from the RHS to V.
-      Known.Zero |= RHSKnown.One  & BKnown.Zero;
-      Known.One  |= RHSKnown.Zero & BKnown.Zero;
-    // assume(v ^ b = a)
-    } else if (match(Arg,
-                     m_c_ICmp(Pred, m_c_Xor(m_V, m_Value(B)), m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits BKnown(BitWidth);
-      computeKnownBits(B, BKnown, Depth+1, Query(Q, I));
-
-      // For those bits in B that are known to be zero, we can propagate known
-      // bits from the RHS to V. For those bits in B that are known to be one,
-      // we can propagate inverted known bits from the RHS to V.
-      Known.Zero |= RHSKnown.Zero & BKnown.Zero;
-      Known.One  |= RHSKnown.One  & BKnown.Zero;
-      Known.Zero |= RHSKnown.One  & BKnown.One;
-      Known.One  |= RHSKnown.Zero & BKnown.One;
-    // assume(~(v ^ b) = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Not(m_c_Xor(m_V, m_Value(B))),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      KnownBits BKnown(BitWidth);
-      computeKnownBits(B, BKnown, Depth+1, Query(Q, I));
-
-      // For those bits in B that are known to be zero, we can propagate
-      // inverted known bits from the RHS to V. For those bits in B that are
-      // known to be one, we can propagate known bits from the RHS to V.
-      Known.Zero |= RHSKnown.One  & BKnown.Zero;
-      Known.One  |= RHSKnown.Zero & BKnown.Zero;
-      Known.Zero |= RHSKnown.Zero & BKnown.One;
-      Known.One  |= RHSKnown.One  & BKnown.One;
-    // assume(v << c = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Shl(m_V, m_ConstantInt(C)),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT) &&
-               C < BitWidth) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      // For those bits in RHS that are known, we can propagate them to known
-      // bits in V shifted to the right by C.
-      RHSKnown.Zero.lshrInPlace(C);
-      Known.Zero |= RHSKnown.Zero;
-      RHSKnown.One.lshrInPlace(C);
-      Known.One  |= RHSKnown.One;
-    // assume(~(v << c) = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Not(m_Shl(m_V, m_ConstantInt(C))),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT) &&
-               C < BitWidth) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      // For those bits in RHS that are known, we can propagate them inverted
-      // to known bits in V shifted to the right by C.
-      RHSKnown.One.lshrInPlace(C);
-      Known.Zero |= RHSKnown.One;
-      RHSKnown.Zero.lshrInPlace(C);
-      Known.One  |= RHSKnown.Zero;
-    // assume(v >> c = a)
-    } else if (match(Arg,
-                     m_c_ICmp(Pred, m_Shr(m_V, m_ConstantInt(C)),
-                              m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT) &&
-               C < BitWidth) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      // For those bits in RHS that are known, we can propagate them to known
-      // bits in V shifted to the right by C.
-      Known.Zero |= RHSKnown.Zero << C;
-      Known.One  |= RHSKnown.One  << C;
-    // assume(~(v >> c) = a)
-    } else if (match(Arg, m_c_ICmp(Pred, m_Not(m_Shr(m_V, m_ConstantInt(C))),
-                                   m_Value(A))) &&
-               Pred == ICmpInst::ICMP_EQ &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT) &&
-               C < BitWidth) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-      // For those bits in RHS that are known, we can propagate them inverted
-      // to known bits in V shifted to the right by C.
-      Known.Zero |= RHSKnown.One  << C;
-      Known.One  |= RHSKnown.Zero << C;
-    // assume(v >=_s c) where c is non-negative
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_SGE &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      if (RHSKnown.isNonNegative()) {
-        // We know that the sign bit is zero.
-        Known.makeNonNegative();
-      }
-    // assume(v >_s c) where c is at least -1.
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_SGT &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      if (RHSKnown.isAllOnes() || RHSKnown.isNonNegative()) {
-        // We know that the sign bit is zero.
-        Known.makeNonNegative();
-      }
-    // assume(v <=_s c) where c is negative
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_SLE &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      if (RHSKnown.isNegative()) {
-        // We know that the sign bit is one.
-        Known.makeNegative();
-      }
-    // assume(v <_s c) where c is non-positive
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_SLT &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      if (RHSKnown.isZero() || RHSKnown.isNegative()) {
-        // We know that the sign bit is one.
-        Known.makeNegative();
-      }
-    // assume(v <=_u c)
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_ULE &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      // Whatever high bits in c are zero are known to be zero.
-      Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros());
-      // assume(v <_u c)
-    } else if (match(Arg, m_ICmp(Pred, m_V, m_Value(A))) &&
-               Pred == ICmpInst::ICMP_ULT &&
-               isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(A, RHSKnown, Depth+1, Query(Q, I));
-
-      // If the RHS is known zero, then this assumption must be wrong (nothing
-      // is unsigned less than zero). Signal a conflict and get out of here.
-      if (RHSKnown.isZero()) {
-        Known.Zero.setAllBits();
-        Known.One.setAllBits();
-        break;
-      }
-
-      // Whatever high bits in c are zero are known to be zero (if c is a power
-      // of 2, then one more).
-      if (isKnownToBeAPowerOfTwo(A, false, Depth + 1, Query(Q, I)))
-        Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros() + 1);
-      else
-        Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros());
-    }
-  }
-
-  // If assumptions conflict with each other or previous known bits, then we
-  // have a logical fallacy. It's possible that the assumption is not reachable,
-  // so this isn't a real bug. On the other hand, the program may have undefined
-  // behavior, or we might have a bug in the compiler. We can't assert/crash, so
-  // clear out the known bits, try to warn the user, and hope for the best.
-  if (Known.Zero.intersects(Known.One)) {
-    Known.resetAll();
-
-    if (Q.ORE)
-      Q.ORE->emit([&]() {
-        auto *CxtI = const_cast<Instruction *>(Q.CxtI);
-        return OptimizationRemarkAnalysis("value-tracking", "BadAssumption",
-                                          CxtI)
-               << "Detected conflicting code assumptions. Program may "
-                  "have undefined behavior, or compiler may have "
-                  "internal error.";
-      });
-  }
-}
-
-/// Compute known bits from a shift operator, including those with a
-/// non-constant shift amount. Known is the output of this function. Known2 is a
-/// pre-allocated temporary with the same bit width as Known. KZF and KOF are
-/// operator-specific functions that, given the known-zero or known-one bits
-/// respectively, and a shift amount, compute the implied known-zero or
-/// known-one bits of the shift operator's result respectively for that shift
-/// amount. The results from calling KZF and KOF are conservatively combined for
-/// all permitted shift amounts.
-static void computeKnownBitsFromShiftOperator(
-    const Operator *I, KnownBits &Known, KnownBits &Known2,
-    unsigned Depth, const Query &Q,
-    function_ref<APInt(const APInt &, unsigned)> KZF,
-    function_ref<APInt(const APInt &, unsigned)> KOF) {
-  unsigned BitWidth = Known.getBitWidth();
-
-  if (auto *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
-    unsigned ShiftAmt = SA->getLimitedValue(BitWidth-1);
-
-    computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-    Known.Zero = KZF(Known.Zero, ShiftAmt);
-    Known.One  = KOF(Known.One, ShiftAmt);
-    // If the known bits conflict, this must be an overflowing left shift, so
-    // the shift result is poison. We can return anything we want. Choose 0 for
-    // the best folding opportunity.
-    if (Known.hasConflict())
-      Known.setAllZero();
-
-    return;
-  }
-
-  computeKnownBits(I->getOperand(1), Known, Depth + 1, Q);
-
-  // If the shift amount could be greater than or equal to the bit-width of the
-  // LHS, the value could be poison, but bail out because the check below is
-  // expensive. TODO: Should we just carry on?
-  if ((~Known.Zero).uge(BitWidth)) {
-    Known.resetAll();
-    return;
-  }
-
-  // Note: We cannot use Known.Zero.getLimitedValue() here, because if
-  // BitWidth > 64 and any upper bits are known, we'll end up returning the
-  // limit value (which implies all bits are known).
-  uint64_t ShiftAmtKZ = Known.Zero.zextOrTrunc(64).getZExtValue();
-  uint64_t ShiftAmtKO = Known.One.zextOrTrunc(64).getZExtValue();
-
-  // It would be more-clearly correct to use the two temporaries for this
-  // calculation. Reusing the APInts here to prevent unnecessary allocations.
-  Known.resetAll();
-
-  // If we know the shifter operand is nonzero, we can sometimes infer more
-  // known bits. However this is expensive to compute, so be lazy about it and
-  // only compute it when absolutely necessary.
-  Optional<bool> ShifterOperandIsNonZero;
-
-  // Early exit if we can't constrain any well-defined shift amount.
-  if (!(ShiftAmtKZ & (PowerOf2Ceil(BitWidth) - 1)) &&
-      !(ShiftAmtKO & (PowerOf2Ceil(BitWidth) - 1))) {
-    ShifterOperandIsNonZero = isKnownNonZero(I->getOperand(1), Depth + 1, Q);
-    if (!*ShifterOperandIsNonZero)
-      return;
-  }
-
-  computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-
-  Known.Zero.setAllBits();
-  Known.One.setAllBits();
-  for (unsigned ShiftAmt = 0; ShiftAmt < BitWidth; ++ShiftAmt) {
-    // Combine the shifted known input bits only for those shift amounts
-    // compatible with its known constraints.
-    if ((ShiftAmt & ~ShiftAmtKZ) != ShiftAmt)
-      continue;
-    if ((ShiftAmt | ShiftAmtKO) != ShiftAmt)
-      continue;
-    // If we know the shifter is nonzero, we may be able to infer more known
-    // bits. This check is sunk down as far as possible to avoid the expensive
-    // call to isKnownNonZero if the cheaper checks above fail.
-    if (ShiftAmt == 0) {
-      if (!ShifterOperandIsNonZero.hasValue())
-        ShifterOperandIsNonZero =
-            isKnownNonZero(I->getOperand(1), Depth + 1, Q);
-      if (*ShifterOperandIsNonZero)
-        continue;
-    }
-
-    Known.Zero &= KZF(Known2.Zero, ShiftAmt);
-    Known.One  &= KOF(Known2.One, ShiftAmt);
-  }
-
-  // If the known bits conflict, the result is poison. Return a 0 and hope the
-  // caller can further optimize that.
-  if (Known.hasConflict())
-    Known.setAllZero();
-}
-
-static void computeKnownBitsFromOperator(const Operator *I, KnownBits &Known,
-                                         unsigned Depth, const Query &Q) {
-  unsigned BitWidth = Known.getBitWidth();
-
-  KnownBits Known2(Known);
-  switch (I->getOpcode()) {
-  default: break;
-  case Instruction::Load:
-    if (MDNode *MD =
-            Q.IIQ.getMetadata(cast<LoadInst>(I), LLVMContext::MD_range))
-      computeKnownBitsFromRangeMetadata(*MD, Known);
-    break;
-  case Instruction::And: {
-    // If either the LHS or the RHS are Zero, the result is zero.
-    computeKnownBits(I->getOperand(1), Known, Depth + 1, Q);
-    computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-
-    // Output known-1 bits are only known if set in both the LHS & RHS.
-    Known.One &= Known2.One;
-    // Output known-0 are known to be clear if zero in either the LHS | RHS.
-    Known.Zero |= Known2.Zero;
-
-    // and(x, add (x, -1)) is a common idiom that always clears the low bit;
-    // here we handle the more general case of adding any odd number by
-    // matching the form add(x, add(x, y)) where y is odd.
-    // TODO: This could be generalized to clearing any bit set in y where the
-    // following bit is known to be unset in y.
-    Value *X = nullptr, *Y = nullptr;
-    if (!Known.Zero[0] && !Known.One[0] &&
-        match(I, m_c_BinOp(m_Value(X), m_Add(m_Deferred(X), m_Value(Y))))) {
-      Known2.resetAll();
-      computeKnownBits(Y, Known2, Depth + 1, Q);
-      if (Known2.countMinTrailingOnes() > 0)
-        Known.Zero.setBit(0);
-    }
-    break;
-  }
-  case Instruction::Or:
-    computeKnownBits(I->getOperand(1), Known, Depth + 1, Q);
-    computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-
-    // Output known-0 bits are only known if clear in both the LHS & RHS.
-    Known.Zero &= Known2.Zero;
-    // Output known-1 are known to be set if set in either the LHS | RHS.
-    Known.One |= Known2.One;
-    break;
-  case Instruction::Xor: {
-    computeKnownBits(I->getOperand(1), Known, Depth + 1, Q);
-    computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-
-    // Output known-0 bits are known if clear or set in both the LHS & RHS.
-    APInt KnownZeroOut = (Known.Zero & Known2.Zero) | (Known.One & Known2.One);
-    // Output known-1 are known to be set if set in only one of the LHS, RHS.
-    Known.One = (Known.Zero & Known2.One) | (Known.One & Known2.Zero);
-    Known.Zero = std::move(KnownZeroOut);
-    break;
-  }
-  case Instruction::Mul: {
-    bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I));
-    computeKnownBitsMul(I->getOperand(0), I->getOperand(1), NSW, Known,
-                        Known2, Depth, Q);
-    break;
-  }
-  case Instruction::UDiv: {
-    // For the purposes of computing leading zeros we can conservatively
-    // treat a udiv as a logical right shift by the power of 2 known to
-    // be less than the denominator.
-    computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-    unsigned LeadZ = Known2.countMinLeadingZeros();
-
-    Known2.resetAll();
-    computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q);
-    unsigned RHSMaxLeadingZeros = Known2.countMaxLeadingZeros();
-    if (RHSMaxLeadingZeros != BitWidth)
-      LeadZ = std::min(BitWidth, LeadZ + BitWidth - RHSMaxLeadingZeros - 1);
-
-    Known.Zero.setHighBits(LeadZ);
-    break;
-  }
-  case Instruction::Select: {
-    const Value *LHS, *RHS;
-    SelectPatternFlavor SPF = matchSelectPattern(I, LHS, RHS).Flavor;
-    if (SelectPatternResult::isMinOrMax(SPF)) {
-      computeKnownBits(RHS, Known, Depth + 1, Q);
-      computeKnownBits(LHS, Known2, Depth + 1, Q);
-    } else {
-      computeKnownBits(I->getOperand(2), Known, Depth + 1, Q);
-      computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q);
-    }
-
-    unsigned MaxHighOnes = 0;
-    unsigned MaxHighZeros = 0;
-    if (SPF == SPF_SMAX) {
-      // If both sides are negative, the result is negative.
-      if (Known.isNegative() && Known2.isNegative())
-        // We can derive a lower bound on the result by taking the max of the
-        // leading one bits.
-        MaxHighOnes =
-            std::max(Known.countMinLeadingOnes(), Known2.countMinLeadingOnes());
-      // If either side is non-negative, the result is non-negative.
-      else if (Known.isNonNegative() || Known2.isNonNegative())
-        MaxHighZeros = 1;
-    } else if (SPF == SPF_SMIN) {
-      // If both sides are non-negative, the result is non-negative.
-      if (Known.isNonNegative() && Known2.isNonNegative())
-        // We can derive an upper bound on the result by taking the max of the
-        // leading zero bits.
-        MaxHighZeros = std::max(Known.countMinLeadingZeros(),
-                                Known2.countMinLeadingZeros());
-      // If either side is negative, the result is negative.
-      else if (Known.isNegative() || Known2.isNegative())
-        MaxHighOnes = 1;
-    } else if (SPF == SPF_UMAX) {
-      // We can derive a lower bound on the result by taking the max of the
-      // leading one bits.
-      MaxHighOnes =
-          std::max(Known.countMinLeadingOnes(), Known2.countMinLeadingOnes());
-    } else if (SPF == SPF_UMIN) {
-      // We can derive an upper bound on the result by taking the max of the
-      // leading zero bits.
-      MaxHighZeros =
-          std::max(Known.countMinLeadingZeros(), Known2.countMinLeadingZeros());
-    } else if (SPF == SPF_ABS) {
-      // RHS from matchSelectPattern returns the negation part of abs pattern.
-      // If the negate has an NSW flag we can assume the sign bit of the result
-      // will be 0 because that makes abs(INT_MIN) undefined.
-      if (Q.IIQ.hasNoSignedWrap(cast<Instruction>(RHS)))
-        MaxHighZeros = 1;
-    }
-
-    // Only known if known in both the LHS and RHS.
-    Known.One &= Known2.One;
-    Known.Zero &= Known2.Zero;
-    if (MaxHighOnes > 0)
-      Known.One.setHighBits(MaxHighOnes);
-    if (MaxHighZeros > 0)
-      Known.Zero.setHighBits(MaxHighZeros);
-    break;
-  }
-  case Instruction::FPTrunc:
-  case Instruction::FPExt:
-  case Instruction::FPToUI:
-  case Instruction::FPToSI:
-  case Instruction::SIToFP:
-  case Instruction::UIToFP:
-    break; // Can't work with floating point.
-  case Instruction::PtrToInt:
-  case Instruction::IntToPtr:
-    // Fall through and handle them the same as zext/trunc.
-    LLVM_FALLTHROUGH;
-  case Instruction::ZExt:
-  case Instruction::Trunc: {
-    Type *SrcTy = I->getOperand(0)->getType();
-
-    unsigned SrcBitWidth;
-    // Note that we handle pointer operands here because of inttoptr/ptrtoint
-    // which fall through here.
-    Type *ScalarTy = SrcTy->getScalarType();
-    SrcBitWidth = ScalarTy->isPointerTy() ?
-      Q.DL.getIndexTypeSizeInBits(ScalarTy) :
-      Q.DL.getTypeSizeInBits(ScalarTy);
-
-    assert(SrcBitWidth && "SrcBitWidth can't be zero");
-    Known = Known.zextOrTrunc(SrcBitWidth);
-    computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-    Known = Known.zextOrTrunc(BitWidth);
-    // Any top bits are known to be zero.
-    if (BitWidth > SrcBitWidth)
-      Known.Zero.setBitsFrom(SrcBitWidth);
-    break;
-  }
-  case Instruction::BitCast: {
-    Type *SrcTy = I->getOperand(0)->getType();
-    if (SrcTy->isIntOrPtrTy() &&
-        // TODO: For now, not handling conversions like:
-        // (bitcast i64 %x to <2 x i32>)
-        !I->getType()->isVectorTy()) {
-      computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-      break;
-    }
-    break;
-  }
-  case Instruction::SExt: {
-    // Compute the bits in the result that are not present in the input.
-    unsigned SrcBitWidth = I->getOperand(0)->getType()->getScalarSizeInBits();
-
-    Known = Known.trunc(SrcBitWidth);
-    computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-    // If the sign bit of the input is known set or clear, then we know the
-    // top bits of the result.
-    Known = Known.sext(BitWidth);
-    break;
-  }
-  case Instruction::Shl: {
-    // (shl X, C1) & C2 == 0   iff   (X & C2 >>u C1) == 0
-    bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I));
-    auto KZF = [NSW](const APInt &KnownZero, unsigned ShiftAmt) {
-      APInt KZResult = KnownZero << ShiftAmt;
-      KZResult.setLowBits(ShiftAmt); // Low bits known 0.
-      // If this shift has "nsw" keyword, then the result is either a poison
-      // value or has the same sign bit as the first operand.
-      if (NSW && KnownZero.isSignBitSet())
-        KZResult.setSignBit();
-      return KZResult;
-    };
-
-    auto KOF = [NSW](const APInt &KnownOne, unsigned ShiftAmt) {
-      APInt KOResult = KnownOne << ShiftAmt;
-      if (NSW && KnownOne.isSignBitSet())
-        KOResult.setSignBit();
-      return KOResult;
-    };
-
-    computeKnownBitsFromShiftOperator(I, Known, Known2, Depth, Q, KZF, KOF);
-    break;
-  }
-  case Instruction::LShr: {
-    // (lshr X, C1) & C2 == 0   iff  (-1 >> C1) & C2 == 0
-    auto KZF = [](const APInt &KnownZero, unsigned ShiftAmt) {
-      APInt KZResult = KnownZero.lshr(ShiftAmt);
-      // High bits known zero.
-      KZResult.setHighBits(ShiftAmt);
-      return KZResult;
-    };
-
-    auto KOF = [](const APInt &KnownOne, unsigned ShiftAmt) {
-      return KnownOne.lshr(ShiftAmt);
-    };
-
-    computeKnownBitsFromShiftOperator(I, Known, Known2, Depth, Q, KZF, KOF);
-    break;
-  }
-  case Instruction::AShr: {
-    // (ashr X, C1) & C2 == 0   iff  (-1 >> C1) & C2 == 0
-    auto KZF = [](const APInt &KnownZero, unsigned ShiftAmt) {
-      return KnownZero.ashr(ShiftAmt);
-    };
-
-    auto KOF = [](const APInt &KnownOne, unsigned ShiftAmt) {
-      return KnownOne.ashr(ShiftAmt);
-    };
-
-    computeKnownBitsFromShiftOperator(I, Known, Known2, Depth, Q, KZF, KOF);
-    break;
-  }
-  case Instruction::Sub: {
-    bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I));
-    computeKnownBitsAddSub(false, I->getOperand(0), I->getOperand(1), NSW,
-                           Known, Known2, Depth, Q);
-    break;
-  }
-  case Instruction::Add: {
-    bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I));
-    computeKnownBitsAddSub(true, I->getOperand(0), I->getOperand(1), NSW,
-                           Known, Known2, Depth, Q);
-    break;
-  }
-  case Instruction::SRem:
-    if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
-      APInt RA = Rem->getValue().abs();
-      if (RA.isPowerOf2()) {
-        APInt LowBits = RA - 1;
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-
-        // The low bits of the first operand are unchanged by the srem.
-        Known.Zero = Known2.Zero & LowBits;
-        Known.One = Known2.One & LowBits;
-
-        // If the first operand is non-negative or has all low bits zero, then
-        // the upper bits are all zero.
-        if (Known2.isNonNegative() || LowBits.isSubsetOf(Known2.Zero))
-          Known.Zero |= ~LowBits;
-
-        // If the first operand is negative and not all low bits are zero, then
-        // the upper bits are all one.
-        if (Known2.isNegative() && LowBits.intersects(Known2.One))
-          Known.One |= ~LowBits;
-
-        assert((Known.Zero & Known.One) == 0 && "Bits known to be one AND zero?");
-        break;
-      }
-    }
-
-    // The sign bit is the LHS's sign bit, except when the result of the
-    // remainder is zero.
-    computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-    // If it's known zero, our sign bit is also zero.
-    if (Known2.isNonNegative())
-      Known.makeNonNegative();
-
-    break;
-  case Instruction::URem: {
-    if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
-      const APInt &RA = Rem->getValue();
-      if (RA.isPowerOf2()) {
-        APInt LowBits = (RA - 1);
-        computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-        Known.Zero |= ~LowBits;
-        Known.One &= LowBits;
-        break;
-      }
-    }
-
-    // Since the result is less than or equal to either operand, any leading
-    // zero bits in either operand must also exist in the result.
-    computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-    computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q);
-
-    unsigned Leaders =
-        std::max(Known.countMinLeadingZeros(), Known2.countMinLeadingZeros());
-    Known.resetAll();
-    Known.Zero.setHighBits(Leaders);
-    break;
-  }
-
-  case Instruction::Alloca: {
-    const AllocaInst *AI = cast<AllocaInst>(I);
-    unsigned Align = AI->getAlignment();
-    if (Align == 0)
-      Align = Q.DL.getABITypeAlignment(AI->getAllocatedType());
-
-    if (Align > 0)
-      Known.Zero.setLowBits(countTrailingZeros(Align));
-    break;
-  }
-  case Instruction::GetElementPtr: {
-    // Analyze all of the subscripts of this getelementptr instruction
-    // to determine if we can prove known low zero bits.
-    KnownBits LocalKnown(BitWidth);
-    computeKnownBits(I->getOperand(0), LocalKnown, Depth + 1, Q);
-    unsigned TrailZ = LocalKnown.countMinTrailingZeros();
-
-    gep_type_iterator GTI = gep_type_begin(I);
-    for (unsigned i = 1, e = I->getNumOperands(); i != e; ++i, ++GTI) {
-      Value *Index = I->getOperand(i);
-      if (StructType *STy = GTI.getStructTypeOrNull()) {
-        // Handle struct member offset arithmetic.
-
-        // Handle case when index is vector zeroinitializer
-        Constant *CIndex = cast<Constant>(Index);
-        if (CIndex->isZeroValue())
-          continue;
-
-        if (CIndex->getType()->isVectorTy())
-          Index = CIndex->getSplatValue();
-
-        unsigned Idx = cast<ConstantInt>(Index)->getZExtValue();
-        const StructLayout *SL = Q.DL.getStructLayout(STy);
-        uint64_t Offset = SL->getElementOffset(Idx);
-        TrailZ = std::min<unsigned>(TrailZ,
-                                    countTrailingZeros(Offset));
-      } else {
-        // Handle array index arithmetic.
-        Type *IndexedTy = GTI.getIndexedType();
-        if (!IndexedTy->isSized()) {
-          TrailZ = 0;
-          break;
-        }
-        unsigned GEPOpiBits = Index->getType()->getScalarSizeInBits();
-        uint64_t TypeSize = Q.DL.getTypeAllocSize(IndexedTy);
-        LocalKnown.Zero = LocalKnown.One = APInt(GEPOpiBits, 0);
-        computeKnownBits(Index, LocalKnown, Depth + 1, Q);
-        TrailZ = std::min(TrailZ,
-                          unsigned(countTrailingZeros(TypeSize) +
-                                   LocalKnown.countMinTrailingZeros()));
-      }
-    }
-
-    Known.Zero.setLowBits(TrailZ);
-    break;
-  }
-  case Instruction::PHI: {
-    const PHINode *P = cast<PHINode>(I);
-    // Handle the case of a simple two-predecessor recurrence PHI.
-    // There's a lot more that could theoretically be done here, but
-    // this is sufficient to catch some interesting cases.
-    if (P->getNumIncomingValues() == 2) {
-      for (unsigned i = 0; i != 2; ++i) {
-        Value *L = P->getIncomingValue(i);
-        Value *R = P->getIncomingValue(!i);
-        Operator *LU = dyn_cast<Operator>(L);
-        if (!LU)
-          continue;
-        unsigned Opcode = LU->getOpcode();
-        // Check for operations that have the property that if
-        // both their operands have low zero bits, the result
-        // will have low zero bits.
-        if (Opcode == Instruction::Add ||
-            Opcode == Instruction::Sub ||
-            Opcode == Instruction::And ||
-            Opcode == Instruction::Or ||
-            Opcode == Instruction::Mul) {
-          Value *LL = LU->getOperand(0);
-          Value *LR = LU->getOperand(1);
-          // Find a recurrence.
-          if (LL == I)
-            L = LR;
-          else if (LR == I)
-            L = LL;
-          else
-            break;
-          // Ok, we have a PHI of the form L op= R. Check for low
-          // zero bits.
-          computeKnownBits(R, Known2, Depth + 1, Q);
-
-          // We need to take the minimum number of known bits
-          KnownBits Known3(Known);
-          computeKnownBits(L, Known3, Depth + 1, Q);
-
-          Known.Zero.setLowBits(std::min(Known2.countMinTrailingZeros(),
-                                         Known3.countMinTrailingZeros()));
-
-          auto *OverflowOp = dyn_cast<OverflowingBinaryOperator>(LU);
-          if (OverflowOp && Q.IIQ.hasNoSignedWrap(OverflowOp)) {
-            // If initial value of recurrence is nonnegative, and we are adding
-            // a nonnegative number with nsw, the result can only be nonnegative
-            // or poison value regardless of the number of times we execute the
-            // add in phi recurrence. If initial value is negative and we are
-            // adding a negative number with nsw, the result can only be
-            // negative or poison value. Similar arguments apply to sub and mul.
-            //
-            // (add non-negative, non-negative) --> non-negative
-            // (add negative, negative) --> negative
-            if (Opcode == Instruction::Add) {
-              if (Known2.isNonNegative() && Known3.isNonNegative())
-                Known.makeNonNegative();
-              else if (Known2.isNegative() && Known3.isNegative())
-                Known.makeNegative();
-            }
-
-            // (sub nsw non-negative, negative) --> non-negative
-            // (sub nsw negative, non-negative) --> negative
-            else if (Opcode == Instruction::Sub && LL == I) {
-              if (Known2.isNonNegative() && Known3.isNegative())
-                Known.makeNonNegative();
-              else if (Known2.isNegative() && Known3.isNonNegative())
-                Known.makeNegative();
-            }
-
-            // (mul nsw non-negative, non-negative) --> non-negative
-            else if (Opcode == Instruction::Mul && Known2.isNonNegative() &&
-                     Known3.isNonNegative())
-              Known.makeNonNegative();
-          }
-
-          break;
-        }
-      }
-    }
-
-    // Unreachable blocks may have zero-operand PHI nodes.
-    if (P->getNumIncomingValues() == 0)
-      break;
-
-    // Otherwise take the unions of the known bit sets of the operands,
-    // taking conservative care to avoid excessive recursion.
-    if (Depth < MaxDepth - 1 && !Known.Zero && !Known.One) {
-      // Skip if every incoming value references to ourself.
-      if (dyn_cast_or_null<UndefValue>(P->hasConstantValue()))
-        break;
-
-      Known.Zero.setAllBits();
-      Known.One.setAllBits();
-      for (Value *IncValue : P->incoming_values()) {
-        // Skip direct self references.
-        if (IncValue == P) continue;
-
-        Known2 = KnownBits(BitWidth);
-        // Recurse, but cap the recursion to one level, because we don't
-        // want to waste time spinning around in loops.
-        computeKnownBits(IncValue, Known2, MaxDepth - 1, Q);
-        Known.Zero &= Known2.Zero;
-        Known.One &= Known2.One;
-        // If all bits have been ruled out, there's no need to check
-        // more operands.
-        if (!Known.Zero && !Known.One)
-          break;
-      }
-    }
-    break;
-  }
-  case Instruction::Call:
-  case Instruction::Invoke:
-    // If range metadata is attached to this call, set known bits from that,
-    // and then intersect with known bits based on other properties of the
-    // function.
-    if (MDNode *MD =
-            Q.IIQ.getMetadata(cast<Instruction>(I), LLVMContext::MD_range))
-      computeKnownBitsFromRangeMetadata(*MD, Known);
-    if (const Value *RV = ImmutableCallSite(I).getReturnedArgOperand()) {
-      computeKnownBits(RV, Known2, Depth + 1, Q);
-      Known.Zero |= Known2.Zero;
-      Known.One |= Known2.One;
-    }
-    if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
-      switch (II->getIntrinsicID()) {
-      default: break;
-      case Intrinsic::bitreverse:
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        Known.Zero |= Known2.Zero.reverseBits();
-        Known.One |= Known2.One.reverseBits();
-        break;
-      case Intrinsic::bswap:
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        Known.Zero |= Known2.Zero.byteSwap();
-        Known.One |= Known2.One.byteSwap();
-        break;
-      case Intrinsic::ctlz: {
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        // If we have a known 1, its position is our upper bound.
-        unsigned PossibleLZ = Known2.One.countLeadingZeros();
-        // If this call is undefined for 0, the result will be less than 2^n.
-        if (II->getArgOperand(1) == ConstantInt::getTrue(II->getContext()))
-          PossibleLZ = std::min(PossibleLZ, BitWidth - 1);
-        unsigned LowBits = Log2_32(PossibleLZ)+1;
-        Known.Zero.setBitsFrom(LowBits);
-        break;
-      }
-      case Intrinsic::cttz: {
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        // If we have a known 1, its position is our upper bound.
-        unsigned PossibleTZ = Known2.One.countTrailingZeros();
-        // If this call is undefined for 0, the result will be less than 2^n.
-        if (II->getArgOperand(1) == ConstantInt::getTrue(II->getContext()))
-          PossibleTZ = std::min(PossibleTZ, BitWidth - 1);
-        unsigned LowBits = Log2_32(PossibleTZ)+1;
-        Known.Zero.setBitsFrom(LowBits);
-        break;
-      }
-      case Intrinsic::ctpop: {
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        // We can bound the space the count needs.  Also, bits known to be zero
-        // can't contribute to the population.
-        unsigned BitsPossiblySet = Known2.countMaxPopulation();
-        unsigned LowBits = Log2_32(BitsPossiblySet)+1;
-        Known.Zero.setBitsFrom(LowBits);
-        // TODO: we could bound KnownOne using the lower bound on the number
-        // of bits which might be set provided by popcnt KnownOne2.
-        break;
-      }
-      case Intrinsic::fshr:
-      case Intrinsic::fshl: {
-        const APInt *SA;
-        if (!match(I->getOperand(2), m_APInt(SA)))
-          break;
-
-        // Normalize to funnel shift left.
-        uint64_t ShiftAmt = SA->urem(BitWidth);
-        if (II->getIntrinsicID() == Intrinsic::fshr)
-          ShiftAmt = BitWidth - ShiftAmt;
-
-        KnownBits Known3(Known);
-        computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q);
-        computeKnownBits(I->getOperand(1), Known3, Depth + 1, Q);
-
-        Known.Zero =
-            Known2.Zero.shl(ShiftAmt) | Known3.Zero.lshr(BitWidth - ShiftAmt);
-        Known.One =
-            Known2.One.shl(ShiftAmt) | Known3.One.lshr(BitWidth - ShiftAmt);
-        break;
-      }
-      case Intrinsic::x86_sse42_crc32_64_64:
-        Known.Zero.setBitsFrom(32);
-        break;
-      }
-    }
-    break;
-  case Instruction::ExtractElement:
-    // Look through extract element. At the moment we keep this simple and skip
-    // tracking the specific element. But at least we might find information
-    // valid for all elements of the vector (for example if vector is sign
-    // extended, shifted, etc).
-    computeKnownBits(I->getOperand(0), Known, Depth + 1, Q);
-    break;
-  case Instruction::ExtractValue:
-    if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I->getOperand(0))) {
-      const ExtractValueInst *EVI = cast<ExtractValueInst>(I);
-      if (EVI->getNumIndices() != 1) break;
-      if (EVI->getIndices()[0] == 0) {
-        switch (II->getIntrinsicID()) {
-        default: break;
-        case Intrinsic::uadd_with_overflow:
-        case Intrinsic::sadd_with_overflow:
-          computeKnownBitsAddSub(true, II->getArgOperand(0),
-                                 II->getArgOperand(1), false, Known, Known2,
-                                 Depth, Q);
-          break;
-        case Intrinsic::usub_with_overflow:
-        case Intrinsic::ssub_with_overflow:
-          computeKnownBitsAddSub(false, II->getArgOperand(0),
-                                 II->getArgOperand(1), false, Known, Known2,
-                                 Depth, Q);
-          break;
-        case Intrinsic::umul_with_overflow:
-        case Intrinsic::smul_with_overflow:
-          computeKnownBitsMul(II->getArgOperand(0), II->getArgOperand(1), false,
-                              Known, Known2, Depth, Q);
-          break;
-        }
-      }
-    }
-  }
-}
-
-/// Determine which bits of V are known to be either zero or one and return
-/// them.
-KnownBits computeKnownBits(const Value *V, unsigned Depth, const Query &Q) {
-  KnownBits Known(getBitWidth(V->getType(), Q.DL));
-  computeKnownBits(V, Known, Depth, Q);
-  return Known;
-}
-
-/// Determine which bits of V are known to be either zero or one and return
-/// them in the Known bit set.
-///
-/// NOTE: we cannot consider 'undef' to be "IsZero" here.  The problem is that
-/// we cannot optimize based on the assumption that it is zero without changing
-/// it to be an explicit zero.  If we don't change it to zero, other code could
-/// optimized based on the contradictory assumption that it is non-zero.
-/// Because instcombine aggressively folds operations with undef args anyway,
-/// this won't lose us code quality.
-///
-/// This function is defined on values with integer type, values with pointer
-/// type, and vectors of integers.  In the case
-/// where V is a vector, known zero, and known one values are the
-/// same width as the vector element, and the bit is set only if it is true
-/// for all of the elements in the vector.
-void computeKnownBits(const Value *V, KnownBits &Known, unsigned Depth,
-                      const Query &Q) {
-  assert(V && "No Value?");
-  assert(Depth <= MaxDepth && "Limit Search Depth");
-  unsigned BitWidth = Known.getBitWidth();
-
-  assert((V->getType()->isIntOrIntVectorTy(BitWidth) ||
-          V->getType()->isPtrOrPtrVectorTy()) &&
-         "Not integer or pointer type!");
-
-  Type *ScalarTy = V->getType()->getScalarType();
-  unsigned ExpectedWidth = ScalarTy->isPointerTy() ?
-    Q.DL.getIndexTypeSizeInBits(ScalarTy) : Q.DL.getTypeSizeInBits(ScalarTy);
-  assert(ExpectedWidth == BitWidth && "V and Known should have same BitWidth");
-  (void)BitWidth;
-  (void)ExpectedWidth;
-
-  const APInt *C;
-  if (match(V, m_APInt(C))) {
-    // We know all of the bits for a scalar constant or a splat vector constant!
-    Known.One = *C;
-    Known.Zero = ~Known.One;
-    return;
-  }
-  // Null and aggregate-zero are all-zeros.
-  if (isa<ConstantPointerNull>(V) || isa<ConstantAggregateZero>(V)) {
-    Known.setAllZero();
-    return;
-  }
-  // Handle a constant vector by taking the intersection of the known bits of
-  // each element.
-  if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V)) {
-    // We know that CDS must be a vector of integers. Take the intersection of
-    // each element.
-    Known.Zero.setAllBits(); Known.One.setAllBits();
-    for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
-      APInt Elt = CDS->getElementAsAPInt(i);
-      Known.Zero &= ~Elt;
-      Known.One &= Elt;
-    }
-    return;
-  }
-
-  if (const auto *CV = dyn_cast<ConstantVector>(V)) {
-    // We know that CV must be a vector of integers. Take the intersection of
-    // each element.
-    Known.Zero.setAllBits(); Known.One.setAllBits();
-    for (unsigned i = 0, e = CV->getNumOperands(); i != e; ++i) {
-      Constant *Element = CV->getAggregateElement(i);
-      auto *ElementCI = dyn_cast_or_null<ConstantInt>(Element);
-      if (!ElementCI) {
-        Known.resetAll();
-        return;
-      }
-      const APInt &Elt = ElementCI->getValue();
-      Known.Zero &= ~Elt;
-      Known.One &= Elt;
-    }
-    return;
-  }
-
-  // Start out not knowing anything.
-  Known.resetAll();
-
-  // We can't imply anything about undefs.
-  if (isa<UndefValue>(V))
-    return;
-
-  // There's no point in looking through other users of ConstantData for
-  // assumptions.  Confirm that we've handled them all.
-  assert(!isa<ConstantData>(V) && "Unhandled constant data!");
-
-  // Limit search depth.
-  // All recursive calls that increase depth must come after this.
-  if (Depth == MaxDepth)
-    return;
-
-  // A weak GlobalAlias is totally unknown. A non-weak GlobalAlias has
-  // the bits of its aliasee.
-  if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
-    if (!GA->isInterposable())
-      computeKnownBits(GA->getAliasee(), Known, Depth + 1, Q);
-    return;
-  }
-
-  if (const Operator *I = dyn_cast<Operator>(V))
-    computeKnownBitsFromOperator(I, Known, Depth, Q);
-
-  // Aligned pointers have trailing zeros - refine Known.Zero set
-  if (V->getType()->isPointerTy()) {
-    unsigned Align = V->getPointerAlignment(Q.DL);
-    if (Align)
-      Known.Zero.setLowBits(countTrailingZeros(Align));
-  }
-
-  // computeKnownBitsFromAssume strictly refines Known.
-  // Therefore, we run them after computeKnownBitsFromOperator.
-
-  // Check whether a nearby assume intrinsic can determine some known bits.
-  computeKnownBitsFromAssume(V, Known, Depth, Q);
-
-  assert((Known.Zero & Known.One) == 0 && "Bits known to be one AND zero?");
-}
-
-/// Return true if the given value is known to have exactly one
-/// bit set when defined. For vectors return true if every element is known to
-/// be a power of two when defined. Supports values with integer or pointer
-/// types and vectors of integers.
-bool isKnownToBeAPowerOfTwo(const Value *V, bool OrZero, unsigned Depth,
-                            const Query &Q) {
-  assert(Depth <= MaxDepth && "Limit Search Depth");
-
-  // Attempt to match against constants.
-  if (OrZero && match(V, m_Power2OrZero()))
-      return true;
-  if (match(V, m_Power2()))
-      return true;
-
-  // 1 << X is clearly a power of two if the one is not shifted off the end.  If
-  // it is shifted off the end then the result is undefined.
-  if (match(V, m_Shl(m_One(), m_Value())))
-    return true;
-
-  // (signmask) >>l X is clearly a power of two if the one is not shifted off
-  // the bottom.  If it is shifted off the bottom then the result is undefined.
-  if (match(V, m_LShr(m_SignMask(), m_Value())))
-    return true;
-
-  // The remaining tests are all recursive, so bail out if we hit the limit.
-  if (Depth++ == MaxDepth)
-    return false;
-
-  Value *X = nullptr, *Y = nullptr;
-  // A shift left or a logical shift right of a power of two is a power of two
-  // or zero.
-  if (OrZero && (match(V, m_Shl(m_Value(X), m_Value())) ||
-                 match(V, m_LShr(m_Value(X), m_Value()))))
-    return isKnownToBeAPowerOfTwo(X, /*OrZero*/ true, Depth, Q);
-
-  if (const ZExtInst *ZI = dyn_cast<ZExtInst>(V))
-    return isKnownToBeAPowerOfTwo(ZI->getOperand(0), OrZero, Depth, Q);
-
-  if (const SelectInst *SI = dyn_cast<SelectInst>(V))
-    return isKnownToBeAPowerOfTwo(SI->getTrueValue(), OrZero, Depth, Q) &&
-           isKnownToBeAPowerOfTwo(SI->getFalseValue(), OrZero, Depth, Q);
-
-  if (OrZero && match(V, m_And(m_Value(X), m_Value(Y)))) {
-    // A power of two and'd with anything is a power of two or zero.
-    if (isKnownToBeAPowerOfTwo(X, /*OrZero*/ true, Depth, Q) ||
-        isKnownToBeAPowerOfTwo(Y, /*OrZero*/ true, Depth, Q))
-      return true;
-    // X & (-X) is always a power of two or zero.
-    if (match(X, m_Neg(m_Specific(Y))) || match(Y, m_Neg(m_Specific(X))))
-      return true;
-    return false;
-  }
-
-  // Adding a power-of-two or zero to the same power-of-two or zero yields
-  // either the original power-of-two, a larger power-of-two or zero.
-  if (match(V, m_Add(m_Value(X), m_Value(Y)))) {
-    const OverflowingBinaryOperator *VOBO = cast<OverflowingBinaryOperator>(V);
-    if (OrZero || Q.IIQ.hasNoUnsignedWrap(VOBO) ||
-        Q.IIQ.hasNoSignedWrap(VOBO)) {
-      if (match(X, m_And(m_Specific(Y), m_Value())) ||
-          match(X, m_And(m_Value(), m_Specific(Y))))
-        if (isKnownToBeAPowerOfTwo(Y, OrZero, Depth, Q))
-          return true;
-      if (match(Y, m_And(m_Specific(X), m_Value())) ||
-          match(Y, m_And(m_Value(), m_Specific(X))))
-        if (isKnownToBeAPowerOfTwo(X, OrZero, Depth, Q))
-          return true;
-
-      unsigned BitWidth = V->getType()->getScalarSizeInBits();
-      KnownBits LHSBits(BitWidth);
-      computeKnownBits(X, LHSBits, Depth, Q);
-
-      KnownBits RHSBits(BitWidth);
-      computeKnownBits(Y, RHSBits, Depth, Q);
-      // If i8 V is a power of two or zero:
-      //  ZeroBits: 1 1 1 0 1 1 1 1
-      // ~ZeroBits: 0 0 0 1 0 0 0 0
-      if ((~(LHSBits.Zero & RHSBits.Zero)).isPowerOf2())
-        // If OrZero isn't set, we cannot give back a zero result.
-        // Make sure either the LHS or RHS has a bit set.
-        if (OrZero || RHSBits.One.getBoolValue() || LHSBits.One.getBoolValue())
-          return true;
-    }
-  }
-
-  // An exact divide or right shift can only shift off zero bits, so the result
-  // is a power of two only if the first operand is a power of two and not
-  // copying a sign bit (sdiv int_min, 2).
-  if (match(V, m_Exact(m_LShr(m_Value(), m_Value()))) ||
-      match(V, m_Exact(m_UDiv(m_Value(), m_Value())))) {
-    return isKnownToBeAPowerOfTwo(cast<Operator>(V)->getOperand(0), OrZero,
-                                  Depth, Q);
-  }
-
-  return false;
-}
-
-/// Test whether a GEP's result is known to be non-null.
-///
-/// Uses properties inherent in a GEP to try to determine whether it is known
-/// to be non-null.
-///
-/// Currently this routine does not support vector GEPs.
-static bool isGEPKnownNonNull(const GEPOperator *GEP, unsigned Depth,
-                              const Query &Q) {
-  const Function *F = nullptr;
-  if (const Instruction *I = dyn_cast<Instruction>(GEP))
-    F = I->getFunction();
-
-  if (!GEP->isInBounds() ||
-      NullPointerIsDefined(F, GEP->getPointerAddressSpace()))
-    return false;
-
-  // FIXME: Support vector-GEPs.
-  assert(GEP->getType()->isPointerTy() && "We only support plain pointer GEP");
-
-  // If the base pointer is non-null, we cannot walk to a null address with an
-  // inbounds GEP in address space zero.
-  if (isKnownNonZero(GEP->getPointerOperand(), Depth, Q))
-    return true;
-
-  // Walk the GEP operands and see if any operand introduces a non-zero offset.
-  // If so, then the GEP cannot produce a null pointer, as doing so would
-  // inherently violate the inbounds contract within address space zero.
-  for (gep_type_iterator GTI = gep_type_begin(GEP), GTE = gep_type_end(GEP);
-       GTI != GTE; ++GTI) {
-    // Struct types are easy -- they must always be indexed by a constant.
-    if (StructType *STy = GTI.getStructTypeOrNull()) {
-      ConstantInt *OpC = cast<ConstantInt>(GTI.getOperand());
-      unsigned ElementIdx = OpC->getZExtValue();
-      const StructLayout *SL = Q.DL.getStructLayout(STy);
-      uint64_t ElementOffset = SL->getElementOffset(ElementIdx);
-      if (ElementOffset > 0)
-        return true;
-      continue;
-    }
-
-    // If we have a zero-sized type, the index doesn't matter. Keep looping.
-    if (Q.DL.getTypeAllocSize(GTI.getIndexedType()) == 0)
-      continue;
-
-    // Fast path the constant operand case both for efficiency and so we don't
-    // increment Depth when just zipping down an all-constant GEP.
-    if (ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand())) {
-      if (!OpC->isZero())
-        return true;
-      continue;
-    }
-
-    // We post-increment Depth here because while isKnownNonZero increments it
-    // as well, when we pop back up that increment won't persist. We don't want
-    // to recurse 10k times just because we have 10k GEP operands. We don't
-    // bail completely out because we want to handle constant GEPs regardless
-    // of depth.
-    if (Depth++ >= MaxDepth)
-      continue;
-
-    if (isKnownNonZero(GTI.getOperand(), Depth, Q))
-      return true;
-  }
-
-  return false;
-}
-
-static bool isKnownNonNullFromDominatingCondition(const Value *V,
-                                                  const Instruction *CtxI,
-                                                  const DominatorTree *DT) {
-  assert(V->getType()->isPointerTy() && "V must be pointer type");
-  assert(!isa<ConstantData>(V) && "Did not expect ConstantPointerNull");
-
-  if (!CtxI || !DT)
-    return false;
-
-  unsigned NumUsesExplored = 0;
-  for (auto *U : V->users()) {
-    // Avoid massive lists
-    if (NumUsesExplored >= DomConditionsMaxUses)
-      break;
-    NumUsesExplored++;
-
-    // If the value is used as an argument to a call or invoke, then argument
-    // attributes may provide an answer about null-ness.
-    if (auto CS = ImmutableCallSite(U))
-      if (auto *CalledFunc = CS.getCalledFunction())
-        for (const Argument &Arg : CalledFunc->args())
-          if (CS.getArgOperand(Arg.getArgNo()) == V &&
-              Arg.hasNonNullAttr() && DT->dominates(CS.getInstruction(), CtxI))
-            return true;
-
-    // Consider only compare instructions uniquely controlling a branch
-    CmpInst::Predicate Pred;
-    if (!match(const_cast<User *>(U),
-               m_c_ICmp(Pred, m_Specific(V), m_Zero())) ||
-        (Pred != ICmpInst::ICMP_EQ && Pred != ICmpInst::ICMP_NE))
-      continue;
-
-    SmallVector<const User *, 4> WorkList;
-    SmallPtrSet<const User *, 4> Visited;
-    for (auto *CmpU : U->users()) {
-      assert(WorkList.empty() && "Should be!");
-      if (Visited.insert(CmpU).second)
-        WorkList.push_back(CmpU);
-
-      while (!WorkList.empty()) {
-        auto *Curr = WorkList.pop_back_val();
-
-        // If a user is an AND, add all its users to the work list. We only
-        // propagate "pred != null" condition through AND because it is only
-        // correct to assume that all conditions of AND are met in true branch.
-        // TODO: Support similar logic of OR and EQ predicate?
-        if (Pred == ICmpInst::ICMP_NE)
-          if (auto *BO = dyn_cast<BinaryOperator>(Curr))
-            if (BO->getOpcode() == Instruction::And) {
-              for (auto *BOU : BO->users())
-                if (Visited.insert(BOU).second)
-                  WorkList.push_back(BOU);
-              continue;
-            }
-
-        if (const BranchInst *BI = dyn_cast<BranchInst>(Curr)) {
-          assert(BI->isConditional() && "uses a comparison!");
-
-          BasicBlock *NonNullSuccessor =
-              BI->getSuccessor(Pred == ICmpInst::ICMP_EQ ? 1 : 0);
-          BasicBlockEdge Edge(BI->getParent(), NonNullSuccessor);
-          if (Edge.isSingleEdge() && DT->dominates(Edge, CtxI->getParent()))
-            return true;
-        } else if (Pred == ICmpInst::ICMP_NE && isGuard(Curr) &&
-                   DT->dominates(cast<Instruction>(Curr), CtxI)) {
-          return true;
-        }
-      }
-    }
-  }
-
-  return false;
-}
-
-/// Does the 'Range' metadata (which must be a valid MD_range operand list)
-/// ensure that the value it's attached to is never Value?  'RangeType' is
-/// is the type of the value described by the range.
-static bool rangeMetadataExcludesValue(const MDNode* Ranges, const APInt& Value) {
-  const unsigned NumRanges = Ranges->getNumOperands() / 2;
-  assert(NumRanges >= 1);
-  for (unsigned i = 0; i < NumRanges; ++i) {
-    ConstantInt *Lower =
-        mdconst::extract<ConstantInt>(Ranges->getOperand(2 * i + 0));
-    ConstantInt *Upper =
-        mdconst::extract<ConstantInt>(Ranges->getOperand(2 * i + 1));
-    ConstantRange Range(Lower->getValue(), Upper->getValue());
-    if (Range.contains(Value))
-      return false;
-  }
-  return true;
-}
-
-/// Return true if the given value is known to be non-zero when defined. For
-/// vectors, return true if every element is known to be non-zero when
-/// defined. For pointers, if the context instruction and dominator tree are
-/// specified, perform context-sensitive analysis and return true if the
-/// pointer couldn't possibly be null at the specified instruction.
-/// Supports values with integer or pointer type and vectors of integers.
-bool isKnownNonZero(const Value *V, unsigned Depth, const Query &Q) {
-  if (auto *C = dyn_cast<Constant>(V)) {
-    if (C->isNullValue())
-      return false;
-    if (isa<ConstantInt>(C))
-      // Must be non-zero due to null test above.
-      return true;
-
-    // For constant vectors, check that all elements are undefined or known
-    // non-zero to determine that the whole vector is known non-zero.
-    if (auto *VecTy = dyn_cast<VectorType>(C->getType())) {
-      for (unsigned i = 0, e = VecTy->getNumElements(); i != e; ++i) {
-        Constant *Elt = C->getAggregateElement(i);
-        if (!Elt || Elt->isNullValue())
-          return false;
-        if (!isa<UndefValue>(Elt) && !isa<ConstantInt>(Elt))
-          return false;
-      }
-      return true;
-    }
-
-    // A global variable in address space 0 is non null unless extern weak
-    // or an absolute symbol reference. Other address spaces may have null as a
-    // valid address for a global, so we can't assume anything.
-    if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
-      if (!GV->isAbsoluteSymbolRef() && !GV->hasExternalWeakLinkage() &&
-          GV->getType()->getAddressSpace() == 0)
-        return true;
-    } else
-      return false;
-  }
-
-  if (auto *I = dyn_cast<Instruction>(V)) {
-    if (MDNode *Ranges = Q.IIQ.getMetadata(I, LLVMContext::MD_range)) {
-      // If the possible ranges don't contain zero, then the value is
-      // definitely non-zero.
-      if (auto *Ty = dyn_cast<IntegerType>(V->getType())) {
-        const APInt ZeroValue(Ty->getBitWidth(), 0);
-        if (rangeMetadataExcludesValue(Ranges, ZeroValue))
-          return true;
-      }
-    }
-  }
-
-  // Some of the tests below are recursive, so bail out if we hit the limit.
-  if (Depth++ >= MaxDepth)
-    return false;
-
-  // Check for pointer simplifications.
-  if (V->getType()->isPointerTy()) {
-    // Alloca never returns null, malloc might.
-    if (isa<AllocaInst>(V) && Q.DL.getAllocaAddrSpace() == 0)
-      return true;
-
-    // A byval, inalloca, or nonnull argument is never null.
-    if (const Argument *A = dyn_cast<Argument>(V))
-      if (A->hasByValOrInAllocaAttr() || A->hasNonNullAttr())
-        return true;
-
-    // A Load tagged with nonnull metadata is never null.
-    if (const LoadInst *LI = dyn_cast<LoadInst>(V))
-      if (Q.IIQ.getMetadata(LI, LLVMContext::MD_nonnull))
-        return true;
-
-    if (const auto *Call = dyn_cast<CallBase>(V)) {
-      if (Call->isReturnNonNull())
-        return true;
-      if (const auto *RP = getArgumentAliasingToReturnedPointer(Call))
-        return isKnownNonZero(RP, Depth, Q);
-    }
-  }
-
-
-  // Check for recursive pointer simplifications.
-  if (V->getType()->isPointerTy()) {
-    if (isKnownNonNullFromDominatingCondition(V, Q.CxtI, Q.DT))
-      return true;
-
-    if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V))
-      if (isGEPKnownNonNull(GEP, Depth, Q))
-        return true;
-  }
-
-  unsigned BitWidth = getBitWidth(V->getType()->getScalarType(), Q.DL);
-
-  // X | Y != 0 if X != 0 or Y != 0.
-  Value *X = nullptr, *Y = nullptr;
-  if (match(V, m_Or(m_Value(X), m_Value(Y))))
-    return isKnownNonZero(X, Depth, Q) || isKnownNonZero(Y, Depth, Q);
-
-  // ext X != 0 if X != 0.
-  if (isa<SExtInst>(V) || isa<ZExtInst>(V))
-    return isKnownNonZero(cast<Instruction>(V)->getOperand(0), Depth, Q);
-
-  // shl X, Y != 0 if X is odd.  Note that the value of the shift is undefined
-  // if the lowest bit is shifted off the end.
-  if (match(V, m_Shl(m_Value(X), m_Value(Y)))) {
-    // shl nuw can't remove any non-zero bits.
-    const OverflowingBinaryOperator *BO = cast<OverflowingBinaryOperator>(V);
-    if (Q.IIQ.hasNoUnsignedWrap(BO))
-      return isKnownNonZero(X, Depth, Q);
-
-    KnownBits Known(BitWidth);
-    computeKnownBits(X, Known, Depth, Q);
-    if (Known.One[0])
-      return true;
-  }
-  // shr X, Y != 0 if X is negative.  Note that the value of the shift is not
-  // defined if the sign bit is shifted off the end.
-  else if (match(V, m_Shr(m_Value(X), m_Value(Y)))) {
-    // shr exact can only shift out zero bits.
-    const PossiblyExactOperator *BO = cast<PossiblyExactOperator>(V);
-    if (BO->isExact())
-      return isKnownNonZero(X, Depth, Q);
-
-    KnownBits Known = computeKnownBits(X, Depth, Q);
-    if (Known.isNegative())
-      return true;
-
-    // If the shifter operand is a constant, and all of the bits shifted
-    // out are known to be zero, and X is known non-zero then at least one
-    // non-zero bit must remain.
-    if (ConstantInt *Shift = dyn_cast<ConstantInt>(Y)) {
-      auto ShiftVal = Shift->getLimitedValue(BitWidth - 1);
-      // Is there a known one in the portion not shifted out?
-      if (Known.countMaxLeadingZeros() < BitWidth - ShiftVal)
-        return true;
-      // Are all the bits to be shifted out known zero?
-      if (Known.countMinTrailingZeros() >= ShiftVal)
-        return isKnownNonZero(X, Depth, Q);
-    }
-  }
-  // div exact can only produce a zero if the dividend is zero.
-  else if (match(V, m_Exact(m_IDiv(m_Value(X), m_Value())))) {
-    return isKnownNonZero(X, Depth, Q);
-  }
-  // X + Y.
-  else if (match(V, m_Add(m_Value(X), m_Value(Y)))) {
-    KnownBits XKnown = computeKnownBits(X, Depth, Q);
-    KnownBits YKnown = computeKnownBits(Y, Depth, Q);
-
-    // If X and Y are both non-negative (as signed values) then their sum is not
-    // zero unless both X and Y are zero.
-    if (XKnown.isNonNegative() && YKnown.isNonNegative())
-      if (isKnownNonZero(X, Depth, Q) || isKnownNonZero(Y, Depth, Q))
-        return true;
-
-    // If X and Y are both negative (as signed values) then their sum is not
-    // zero unless both X and Y equal INT_MIN.
-    if (XKnown.isNegative() && YKnown.isNegative()) {
-      APInt Mask = APInt::getSignedMaxValue(BitWidth);
-      // The sign bit of X is set.  If some other bit is set then X is not equal
-      // to INT_MIN.
-      if (XKnown.One.intersects(Mask))
-        return true;
-      // The sign bit of Y is set.  If some other bit is set then Y is not equal
-      // to INT_MIN.
-      if (YKnown.One.intersects(Mask))
-        return true;
-    }
-
-    // The sum of a non-negative number and a power of two is not zero.
-    if (XKnown.isNonNegative() &&
-        isKnownToBeAPowerOfTwo(Y, /*OrZero*/ false, Depth, Q))
-      return true;
-    if (YKnown.isNonNegative() &&
-        isKnownToBeAPowerOfTwo(X, /*OrZero*/ false, Depth, Q))
-      return true;
-  }
-  // X * Y.
-  else if (match(V, m_Mul(m_Value(X), m_Value(Y)))) {
-    const OverflowingBinaryOperator *BO = cast<OverflowingBinaryOperator>(V);
-    // If X and Y are non-zero then so is X * Y as long as the multiplication
-    // does not overflow.
-    if ((Q.IIQ.hasNoSignedWrap(BO) || Q.IIQ.hasNoUnsignedWrap(BO)) &&
-        isKnownNonZero(X, Depth, Q) && isKnownNonZero(Y, Depth, Q))
-      return true;
-  }
-  // (C ? X : Y) != 0 if X != 0 and Y != 0.
-  else if (const SelectInst *SI = dyn_cast<SelectInst>(V)) {
-    if (isKnownNonZero(SI->getTrueValue(), Depth, Q) &&
-        isKnownNonZero(SI->getFalseValue(), Depth, Q))
-      return true;
-  }
-  // PHI
-  else if (const PHINode *PN = dyn_cast<PHINode>(V)) {
-    // Try and detect a recurrence that monotonically increases from a
-    // starting value, as these are common as induction variables.
-    if (PN->getNumIncomingValues() == 2) {
-      Value *Start = PN->getIncomingValue(0);
-      Value *Induction = PN->getIncomingValue(1);
-      if (isa<ConstantInt>(Induction) && !isa<ConstantInt>(Start))
-        std::swap(Start, Induction);
-      if (ConstantInt *C = dyn_cast<ConstantInt>(Start)) {
-        if (!C->isZero() && !C->isNegative()) {
-          ConstantInt *X;
-          if (Q.IIQ.UseInstrInfo &&
-              (match(Induction, m_NSWAdd(m_Specific(PN), m_ConstantInt(X))) ||
-               match(Induction, m_NUWAdd(m_Specific(PN), m_ConstantInt(X)))) &&
-              !X->isNegative())
-            return true;
-        }
-      }
-    }
-    // Check if all incoming values are non-zero constant.
-    bool AllNonZeroConstants = llvm::all_of(PN->operands(), [](Value *V) {
-      return isa<ConstantInt>(V) && !cast<ConstantInt>(V)->isZero();
-    });
-    if (AllNonZeroConstants)
-      return true;
-  }
-
-  KnownBits Known(BitWidth);
-  computeKnownBits(V, Known, Depth, Q);
-  return Known.One != 0;
-}
-
-/// Return true if V2 == V1 + X, where X is known non-zero.
-static bool isAddOfNonZero(const Value *V1, const Value *V2, const Query &Q) {
-  const BinaryOperator *BO = dyn_cast<BinaryOperator>(V1);
-  if (!BO || BO->getOpcode() != Instruction::Add)
-    return false;
-  Value *Op = nullptr;
-  if (V2 == BO->getOperand(0))
-    Op = BO->getOperand(1);
-  else if (V2 == BO->getOperand(1))
-    Op = BO->getOperand(0);
-  else
-    return false;
-  return isKnownNonZero(Op, 0, Q);
-}
-
-/// Return true if it is known that V1 != V2.
-static bool isKnownNonEqual(const Value *V1, const Value *V2, const Query &Q) {
-  if (V1 == V2)
-    return false;
-  if (V1->getType() != V2->getType())
-    // We can't look through casts yet.
-    return false;
-  if (isAddOfNonZero(V1, V2, Q) || isAddOfNonZero(V2, V1, Q))
-    return true;
-
-  if (V1->getType()->isIntOrIntVectorTy()) {
-    // Are any known bits in V1 contradictory to known bits in V2? If V1
-    // has a known zero where V2 has a known one, they must not be equal.
-    KnownBits Known1 = computeKnownBits(V1, 0, Q);
-    KnownBits Known2 = computeKnownBits(V2, 0, Q);
-
-    if (Known1.Zero.intersects(Known2.One) ||
-        Known2.Zero.intersects(Known1.One))
-      return true;
-  }
-  return false;
-}
-
-/// Return true if 'V & Mask' is known to be zero.  We use this predicate to
-/// simplify operations downstream. Mask is known to be zero for bits that V
-/// cannot have.
-///
-/// This function is defined on values with integer type, values with pointer
-/// type, and vectors of integers.  In the case
-/// where V is a vector, the mask, known zero, and known one values are the
-/// same width as the vector element, and the bit is set only if it is true
-/// for all of the elements in the vector.
-bool MaskedValueIsZero(const Value *V, const APInt &Mask, unsigned Depth,
-                       const Query &Q) {
-  KnownBits Known(Mask.getBitWidth());
-  computeKnownBits(V, Known, Depth, Q);
-  return Mask.isSubsetOf(Known.Zero);
-}
-
-// Match a signed min+max clamp pattern like smax(smin(In, CHigh), CLow).
-// Returns the input and lower/upper bounds.
-static bool isSignedMinMaxClamp(const Value *Select, const Value *&In,
-                                const APInt *&CLow, const APInt *&CHigh) {
-  assert(isa<Operator>(Select) &&
-         cast<Operator>(Select)->getOpcode() == Instruction::Select &&
-         "Input should be a Select!");
-
-  const Value *LHS, *RHS, *LHS2, *RHS2;
-  SelectPatternFlavor SPF = matchSelectPattern(Select, LHS, RHS).Flavor;
-  if (SPF != SPF_SMAX && SPF != SPF_SMIN)
-    return false;
-
-  if (!match(RHS, m_APInt(CLow)))
-    return false;
-
-  SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2).Flavor;
-  if (getInverseMinMaxFlavor(SPF) != SPF2)
-    return false;
-
-  if (!match(RHS2, m_APInt(CHigh)))
-    return false;
-
-  if (SPF == SPF_SMIN)
-    std::swap(CLow, CHigh);
-
-  In = LHS2;
-  return CLow->sle(*CHigh);
-}
-
-/// For vector constants, loop over the elements and find the constant with the
-/// minimum number of sign bits. Return 0 if the value is not a vector constant
-/// or if any element was not analyzed; otherwise, return the count for the
-/// element with the minimum number of sign bits.
-static unsigned computeNumSignBitsVectorConstant(const Value *V,
-                                                 unsigned TyBits) {
-  const auto *CV = dyn_cast<Constant>(V);
-  if (!CV || !CV->getType()->isVectorTy())
-    return 0;
-
-  unsigned MinSignBits = TyBits;
-  unsigned NumElts = CV->getType()->getVectorNumElements();
-  for (unsigned i = 0; i != NumElts; ++i) {
-    // If we find a non-ConstantInt, bail out.
-    auto *Elt = dyn_cast_or_null<ConstantInt>(CV->getAggregateElement(i));
-    if (!Elt)
-      return 0;
-
-    MinSignBits = std::min(MinSignBits, Elt->getValue().getNumSignBits());
-  }
-
-  return MinSignBits;
-}
-
-static unsigned ComputeNumSignBitsImpl(const Value *V, unsigned Depth,
-                                       const Query &Q);
-
-static unsigned ComputeNumSignBits(const Value *V, unsigned Depth,
-                                   const Query &Q) {
-  unsigned Result = ComputeNumSignBitsImpl(V, Depth, Q);
-  assert(Result > 0 && "At least one sign bit needs to be present!");
-  return Result;
-}
-
-/// Return the number of times the sign bit of the register is replicated into
-/// the other bits. We know that at least 1 bit is always equal to the sign bit
-/// (itself), but other cases can give us information. For example, immediately
-/// after an "ashr X, 2", we know that the top 3 bits are all equal to each
-/// other, so we return 3. For vectors, return the number of sign bits for the
-/// vector element with the minimum number of known sign bits.
-static unsigned ComputeNumSignBitsImpl(const Value *V, unsigned Depth,
-                                       const Query &Q) {
-  assert(Depth <= MaxDepth && "Limit Search Depth");
-
-  // We return the minimum number of sign bits that are guaranteed to be present
-  // in V, so for undef we have to conservatively return 1.  We don't have the
-  // same behavior for poison though -- that's a FIXME today.
-
-  Type *ScalarTy = V->getType()->getScalarType();
-  unsigned TyBits = ScalarTy->isPointerTy() ?
-    Q.DL.getIndexTypeSizeInBits(ScalarTy) :
-    Q.DL.getTypeSizeInBits(ScalarTy);
-
-  unsigned Tmp, Tmp2;
-  unsigned FirstAnswer = 1;
-
-  // Note that ConstantInt is handled by the general computeKnownBits case
-  // below.
-
-  if (Depth == MaxDepth)
-    return 1;  // Limit search depth.
-
-  const Operator *U = dyn_cast<Operator>(V);
-  switch (Operator::getOpcode(V)) {
-  default: break;
-  case Instruction::SExt:
-    Tmp = TyBits - U->getOperand(0)->getType()->getScalarSizeInBits();
-    return ComputeNumSignBits(U->getOperand(0), Depth + 1, Q) + Tmp;
-
-  case Instruction::SDiv: {
-    const APInt *Denominator;
-    // sdiv X, C -> adds log(C) sign bits.
-    if (match(U->getOperand(1), m_APInt(Denominator))) {
-
-      // Ignore non-positive denominator.
-      if (!Denominator->isStrictlyPositive())
-        break;
-
-      // Calculate the incoming numerator bits.
-      unsigned NumBits = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-
-      // Add floor(log(C)) bits to the numerator bits.
-      return std::min(TyBits, NumBits + Denominator->logBase2());
-    }
-    break;
-  }
-
-  case Instruction::SRem: {
-    const APInt *Denominator;
-    // srem X, C -> we know that the result is within [-C+1,C) when C is a
-    // positive constant.  This let us put a lower bound on the number of sign
-    // bits.
-    if (match(U->getOperand(1), m_APInt(Denominator))) {
-
-      // Ignore non-positive denominator.
-      if (!Denominator->isStrictlyPositive())
-        break;
-
-      // Calculate the incoming numerator bits. SRem by a positive constant
-      // can't lower the number of sign bits.
-      unsigned NumrBits =
-          ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-
-      // Calculate the leading sign bit constraints by examining the
-      // denominator.  Given that the denominator is positive, there are two
-      // cases:
-      //
-      //  1. the numerator is positive.  The result range is [0,C) and [0,C) u<
-      //     (1 << ceilLogBase2(C)).
-      //
-      //  2. the numerator is negative.  Then the result range is (-C,0] and
-      //     integers in (-C,0] are either 0 or >u (-1 << ceilLogBase2(C)).
-      //
-      // Thus a lower bound on the number of sign bits is `TyBits -
-      // ceilLogBase2(C)`.
-
-      unsigned ResBits = TyBits - Denominator->ceilLogBase2();
-      return std::max(NumrBits, ResBits);
-    }
-    break;
-  }
-
-  case Instruction::AShr: {
-    Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-    // ashr X, C   -> adds C sign bits.  Vectors too.
-    const APInt *ShAmt;
-    if (match(U->getOperand(1), m_APInt(ShAmt))) {
-      if (ShAmt->uge(TyBits))
-        break;  // Bad shift.
-      unsigned ShAmtLimited = ShAmt->getZExtValue();
-      Tmp += ShAmtLimited;
-      if (Tmp > TyBits) Tmp = TyBits;
-    }
-    return Tmp;
-  }
-  case Instruction::Shl: {
-    const APInt *ShAmt;
-    if (match(U->getOperand(1), m_APInt(ShAmt))) {
-      // shl destroys sign bits.
-      Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-      if (ShAmt->uge(TyBits) ||      // Bad shift.
-          ShAmt->uge(Tmp)) break;    // Shifted all sign bits out.
-      Tmp2 = ShAmt->getZExtValue();
-      return Tmp - Tmp2;
-    }
-    break;
-  }
-  case Instruction::And:
-  case Instruction::Or:
-  case Instruction::Xor:    // NOT is handled here.
-    // Logical binary ops preserve the number of sign bits at the worst.
-    Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-    if (Tmp != 1) {
-      Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q);
-      FirstAnswer = std::min(Tmp, Tmp2);
-      // We computed what we know about the sign bits as our first
-      // answer. Now proceed to the generic code that uses
-      // computeKnownBits, and pick whichever answer is better.
-    }
-    break;
-
-  case Instruction::Select: {
-    // If we have a clamp pattern, we know that the number of sign bits will be
-    // the minimum of the clamp min/max range.
-    const Value *X;
-    const APInt *CLow, *CHigh;
-    if (isSignedMinMaxClamp(U, X, CLow, CHigh))
-      return std::min(CLow->getNumSignBits(), CHigh->getNumSignBits());
-
-    Tmp = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q);
-    if (Tmp == 1) break;
-    Tmp2 = ComputeNumSignBits(U->getOperand(2), Depth + 1, Q);
-    return std::min(Tmp, Tmp2);
-  }
-
-  case Instruction::Add:
-    // Add can have at most one carry bit.  Thus we know that the output
-    // is, at worst, one more bit than the inputs.
-    Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-    if (Tmp == 1) break;
-
-    // Special case decrementing a value (ADD X, -1):
-    if (const auto *CRHS = dyn_cast<Constant>(U->getOperand(1)))
-      if (CRHS->isAllOnesValue()) {
-        KnownBits Known(TyBits);
-        computeKnownBits(U->getOperand(0), Known, Depth + 1, Q);
-
-        // If the input is known to be 0 or 1, the output is 0/-1, which is all
-        // sign bits set.
-        if ((Known.Zero | 1).isAllOnesValue())
-          return TyBits;
-
-        // If we are subtracting one from a positive number, there is no carry
-        // out of the result.
-        if (Known.isNonNegative())
-          return Tmp;
-      }
-
-    Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q);
-    if (Tmp2 == 1) break;
-    return std::min(Tmp, Tmp2)-1;
-
-  case Instruction::Sub:
-    Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q);
-    if (Tmp2 == 1) break;
-
-    // Handle NEG.
-    if (const auto *CLHS = dyn_cast<Constant>(U->getOperand(0)))
-      if (CLHS->isNullValue()) {
-        KnownBits Known(TyBits);
-        computeKnownBits(U->getOperand(1), Known, Depth + 1, Q);
-        // If the input is known to be 0 or 1, the output is 0/-1, which is all
-        // sign bits set.
-        if ((Known.Zero | 1).isAllOnesValue())
-          return TyBits;
-
-        // If the input is known to be positive (the sign bit is known clear),
-        // the output of the NEG has the same number of sign bits as the input.
-        if (Known.isNonNegative())
-          return Tmp2;
-
-        // Otherwise, we treat this like a SUB.
-      }
-
-    // Sub can have at most one carry bit.  Thus we know that the output
-    // is, at worst, one more bit than the inputs.
-    Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-    if (Tmp == 1) break;
-    return std::min(Tmp, Tmp2)-1;
-
-  case Instruction::Mul: {
-    // The output of the Mul can be at most twice the valid bits in the inputs.
-    unsigned SignBitsOp0 = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-    if (SignBitsOp0 == 1) break;
-    unsigned SignBitsOp1 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q);
-    if (SignBitsOp1 == 1) break;
-    unsigned OutValidBits =
-        (TyBits - SignBitsOp0 + 1) + (TyBits - SignBitsOp1 + 1);
-    return OutValidBits > TyBits ? 1 : TyBits - OutValidBits + 1;
-  }
-
-  case Instruction::PHI: {
-    const PHINode *PN = cast<PHINode>(U);
-    unsigned NumIncomingValues = PN->getNumIncomingValues();
-    // Don't analyze large in-degree PHIs.
-    if (NumIncomingValues > 4) break;
-    // Unreachable blocks may have zero-operand PHI nodes.
-    if (NumIncomingValues == 0) break;
-
-    // Take the minimum of all incoming values.  This can't infinitely loop
-    // because of our depth threshold.
-    Tmp = ComputeNumSignBits(PN->getIncomingValue(0), Depth + 1, Q);
-    for (unsigned i = 1, e = NumIncomingValues; i != e; ++i) {
-      if (Tmp == 1) return Tmp;
-      Tmp = std::min(
-          Tmp, ComputeNumSignBits(PN->getIncomingValue(i), Depth + 1, Q));
-    }
-    return Tmp;
-  }
-
-  case Instruction::Trunc:
-    // FIXME: it's tricky to do anything useful for this, but it is an important
-    // case for targets like X86.
-    break;
-
-  case Instruction::ExtractElement:
-    // Look through extract element. At the moment we keep this simple and skip
-    // tracking the specific element. But at least we might find information
-    // valid for all elements of the vector (for example if vector is sign
-    // extended, shifted, etc).
-    return ComputeNumSignBits(U->getOperand(0), Depth + 1, Q);
-
-  case Instruction::ShuffleVector: {
-    // TODO: This is copied almost directly from the SelectionDAG version of
-    //       ComputeNumSignBits. It would be better if we could share common
-    //       code. If not, make sure that changes are translated to the DAG.
-
-    // Collect the minimum number of sign bits that are shared by every vector
-    // element referenced by the shuffle.
-    auto *Shuf = cast<ShuffleVectorInst>(U);
-    int NumElts = Shuf->getOperand(0)->getType()->getVectorNumElements();
-    int NumMaskElts = Shuf->getMask()->getType()->getVectorNumElements();
-    APInt DemandedLHS(NumElts, 0), DemandedRHS(NumElts, 0);
-    for (int i = 0; i != NumMaskElts; ++i) {
-      int M = Shuf->getMaskValue(i);
-      assert(M < NumElts * 2 && "Invalid shuffle mask constant");
-      // For undef elements, we don't know anything about the common state of
-      // the shuffle result.
-      if (M == -1)
-        return 1;
-      if (M < NumElts)
-        DemandedLHS.setBit(M % NumElts);
-      else
-        DemandedRHS.setBit(M % NumElts);
-    }
-    Tmp = std::numeric_limits<unsigned>::max();
-    if (!!DemandedLHS)
-      Tmp = ComputeNumSignBits(Shuf->getOperand(0), Depth + 1, Q);
-    if (!!DemandedRHS) {
-      Tmp2 = ComputeNumSignBits(Shuf->getOperand(1), Depth + 1, Q);
-      Tmp = std::min(Tmp, Tmp2);
-    }
-    // If we don't know anything, early out and try computeKnownBits fall-back.
-    if (Tmp == 1)
-      break;
-    assert(Tmp <= V->getType()->getScalarSizeInBits() &&
-           "Failed to determine minimum sign bits");
-    return Tmp;
-  }
-  }
-
-  // Finally, if we can prove that the top bits of the result are 0's or 1's,
-  // use this information.
-
-  // If we can examine all elements of a vector constant successfully, we're
-  // done (we can't do any better than that). If not, keep trying.
-  if (unsigned VecSignBits = computeNumSignBitsVectorConstant(V, TyBits))
-    return VecSignBits;
-
-  KnownBits Known(TyBits);
-  computeKnownBits(V, Known, Depth, Q);
-
-  // If we know that the sign bit is either zero or one, determine the number of
-  // identical bits in the top of the input value.
-  return std::max(FirstAnswer, Known.countMinSignBits());
-}
-
-/// This function computes the integer multiple of Base that equals V.
-/// If successful, it returns true and returns the multiple in
-/// Multiple. If unsuccessful, it returns false. It looks
-/// through SExt instructions only if LookThroughSExt is true.
-bool llvm::ComputeMultiple(Value *V, unsigned Base, Value *&Multiple,
-                           bool LookThroughSExt, unsigned Depth) {
-  const unsigned MaxDepth = 6;
-
-  assert(V && "No Value?");
-  assert(Depth <= MaxDepth && "Limit Search Depth");
-  assert(V->getType()->isIntegerTy() && "Not integer or pointer type!");
-
-  Type *T = V->getType();
-
-  ConstantInt *CI = dyn_cast<ConstantInt>(V);
-
-  if (Base == 0)
-    return false;
-
-  if (Base == 1) {
-    Multiple = V;
-    return true;
-  }
-
-  ConstantExpr *CO = dyn_cast<ConstantExpr>(V);
-  Constant *BaseVal = ConstantInt::get(T, Base);
-  if (CO && CO == BaseVal) {
-    // Multiple is 1.
-    Multiple = ConstantInt::get(T, 1);
-    return true;
-  }
-
-  if (CI && CI->getZExtValue() % Base == 0) {
-    Multiple = ConstantInt::get(T, CI->getZExtValue() / Base);
-    return true;
-  }
-
-  if (Depth == MaxDepth) return false;  // Limit search depth.
-
-  Operator *I = dyn_cast<Operator>(V);
-  if (!I) return false;
-
-  switch (I->getOpcode()) {
-  default: break;
-  case Instruction::SExt:
-    if (!LookThroughSExt) return false;
-    // otherwise fall through to ZExt
-    LLVM_FALLTHROUGH;
-  case Instruction::ZExt:
-    return ComputeMultiple(I->getOperand(0), Base, Multiple,
-                           LookThroughSExt, Depth+1);
-  case Instruction::Shl:
-  case Instruction::Mul: {
-    Value *Op0 = I->getOperand(0);
-    Value *Op1 = I->getOperand(1);
-
-    if (I->getOpcode() == Instruction::Shl) {
-      ConstantInt *Op1CI = dyn_cast<ConstantInt>(Op1);
-      if (!Op1CI) return false;
-      // Turn Op0 << Op1 into Op0 * 2^Op1
-      APInt Op1Int = Op1CI->getValue();
-      uint64_t BitToSet = Op1Int.getLimitedValue(Op1Int.getBitWidth() - 1);
-      APInt API(Op1Int.getBitWidth(), 0);
-      API.setBit(BitToSet);
-      Op1 = ConstantInt::get(V->getContext(), API);
-    }
-
-    Value *Mul0 = nullptr;
-    if (ComputeMultiple(Op0, Base, Mul0, LookThroughSExt, Depth+1)) {
-      if (Constant *Op1C = dyn_cast<Constant>(Op1))
-        if (Constant *MulC = dyn_cast<Constant>(Mul0)) {
-          if (Op1C->getType()->getPrimitiveSizeInBits() <
-              MulC->getType()->getPrimitiveSizeInBits())
-            Op1C = ConstantExpr::getZExt(Op1C, MulC->getType());
-          if (Op1C->getType()->getPrimitiveSizeInBits() >
-              MulC->getType()->getPrimitiveSizeInBits())
-            MulC = ConstantExpr::getZExt(MulC, Op1C->getType());
-
-          // V == Base * (Mul0 * Op1), so return (Mul0 * Op1)
-          Multiple = ConstantExpr::getMul(MulC, Op1C);
-          return true;
-        }
-
-      if (ConstantInt *Mul0CI = dyn_cast<ConstantInt>(Mul0))
-        if (Mul0CI->getValue() == 1) {
-          // V == Base * Op1, so return Op1
-          Multiple = Op1;
-          return true;
-        }
-    }
-
-    Value *Mul1 = nullptr;
-    if (ComputeMultiple(Op1, Base, Mul1, LookThroughSExt, Depth+1)) {
-      if (Constant *Op0C = dyn_cast<Constant>(Op0))
-        if (Constant *MulC = dyn_cast<Constant>(Mul1)) {
-          if (Op0C->getType()->getPrimitiveSizeInBits() <
-              MulC->getType()->getPrimitiveSizeInBits())
-            Op0C = ConstantExpr::getZExt(Op0C, MulC->getType());
-          if (Op0C->getType()->getPrimitiveSizeInBits() >
-              MulC->getType()->getPrimitiveSizeInBits())
-            MulC = ConstantExpr::getZExt(MulC, Op0C->getType());
-
-          // V == Base * (Mul1 * Op0), so return (Mul1 * Op0)
-          Multiple = ConstantExpr::getMul(MulC, Op0C);
-          return true;
-        }
-
-      if (ConstantInt *Mul1CI = dyn_cast<ConstantInt>(Mul1))
-        if (Mul1CI->getValue() == 1) {
-          // V == Base * Op0, so return Op0
-          Multiple = Op0;
-          return true;
-        }
-    }
-  }
-  }
-
-  // We could not determine if V is a multiple of Base.
-  return false;
-}
-
-Intrinsic::ID llvm::getIntrinsicForCallSite(ImmutableCallSite ICS,
-                                            const TargetLibraryInfo *TLI) {
-  const Function *F = ICS.getCalledFunction();
-  if (!F)
-    return Intrinsic::not_intrinsic;
-
-  if (F->isIntrinsic())
-    return F->getIntrinsicID();
-
-  if (!TLI)
-    return Intrinsic::not_intrinsic;
-
-  LibFunc Func;
-  // We're going to make assumptions on the semantics of the functions, check
-  // that the target knows that it's available in this environment and it does
-  // not have local linkage.
-  if (!F || F->hasLocalLinkage() || !TLI->getLibFunc(*F, Func))
-    return Intrinsic::not_intrinsic;
-
-  if (!ICS.onlyReadsMemory())
-    return Intrinsic::not_intrinsic;
-
-  // Otherwise check if we have a call to a function that can be turned into a
-  // vector intrinsic.
-  switch (Func) {
-  default:
-    break;
-  case LibFunc_sin:
-  case LibFunc_sinf:
-  case LibFunc_sinl:
-    return Intrinsic::sin;
-  case LibFunc_cos:
-  case LibFunc_cosf:
-  case LibFunc_cosl:
-    return Intrinsic::cos;
-  case LibFunc_exp:
-  case LibFunc_expf:
-  case LibFunc_expl:
-    return Intrinsic::exp;
-  case LibFunc_exp2:
-  case LibFunc_exp2f:
-  case LibFunc_exp2l:
-    return Intrinsic::exp2;
-  case LibFunc_log:
-  case LibFunc_logf:
-  case LibFunc_logl:
-    return Intrinsic::log;
-  case LibFunc_log10:
-  case LibFunc_log10f:
-  case LibFunc_log10l:
-    return Intrinsic::log10;
-  case LibFunc_log2:
-  case LibFunc_log2f:
-  case LibFunc_log2l:
-    return Intrinsic::log2;
-  case LibFunc_fabs:
-  case LibFunc_fabsf:
-  case LibFunc_fabsl:
-    return Intrinsic::fabs;
-  case LibFunc_fmin:
-  case LibFunc_fminf:
-  case LibFunc_fminl:
-    return Intrinsic::minnum;
-  case LibFunc_fmax:
-  case LibFunc_fmaxf:
-  case LibFunc_fmaxl:
-    return Intrinsic::maxnum;
-  case LibFunc_copysign:
-  case LibFunc_copysignf:
-  case LibFunc_copysignl:
-    return Intrinsic::copysign;
-  case LibFunc_floor:
-  case LibFunc_floorf:
-  case LibFunc_floorl:
-    return Intrinsic::floor;
-  case LibFunc_ceil:
-  case LibFunc_ceilf:
-  case LibFunc_ceill:
-    return Intrinsic::ceil;
-  case LibFunc_trunc:
-  case LibFunc_truncf:
-  case LibFunc_truncl:
-    return Intrinsic::trunc;
-  case LibFunc_rint:
-  case LibFunc_rintf:
-  case LibFunc_rintl:
-    return Intrinsic::rint;
-  case LibFunc_nearbyint:
-  case LibFunc_nearbyintf:
-  case LibFunc_nearbyintl:
-    return Intrinsic::nearbyint;
-  case LibFunc_round:
-  case LibFunc_roundf:
-  case LibFunc_roundl:
-    return Intrinsic::round;
-  case LibFunc_pow:
-  case LibFunc_powf:
-  case LibFunc_powl:
-    return Intrinsic::pow;
-  case LibFunc_sqrt:
-  case LibFunc_sqrtf:
-  case LibFunc_sqrtl:
-    return Intrinsic::sqrt;
-  }
-
-  return Intrinsic::not_intrinsic;
-}
-
-/// Return true if we can prove that the specified FP value is never equal to
-/// -0.0.
-///
-/// NOTE: this function will need to be revisited when we support non-default
-/// rounding modes!
-bool llvm::CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI,
-                                unsigned Depth) {
-  if (auto *CFP = dyn_cast<ConstantFP>(V))
-    return !CFP->getValueAPF().isNegZero();
-
-  // Limit search depth.
-  if (Depth == MaxDepth)
-    return false;
-
-  auto *Op = dyn_cast<Operator>(V);
-  if (!Op)
-    return false;
-
-  // Check if the nsz fast-math flag is set.
-  if (auto *FPO = dyn_cast<FPMathOperator>(Op))
-    if (FPO->hasNoSignedZeros())
-      return true;
-
-  // (fadd x, 0.0) is guaranteed to return +0.0, not -0.0.
-  if (match(Op, m_FAdd(m_Value(), m_PosZeroFP())))
-    return true;
-
-  // sitofp and uitofp turn into +0.0 for zero.
-  if (isa<SIToFPInst>(Op) || isa<UIToFPInst>(Op))
-    return true;
-
-  if (auto *Call = dyn_cast<CallInst>(Op)) {
-    Intrinsic::ID IID = getIntrinsicForCallSite(Call, TLI);
-    switch (IID) {
-    default:
-      break;
-    // sqrt(-0.0) = -0.0, no other negative results are possible.
-    case Intrinsic::sqrt:
-    case Intrinsic::canonicalize:
-      return CannotBeNegativeZero(Call->getArgOperand(0), TLI, Depth + 1);
-    // fabs(x) != -0.0
-    case Intrinsic::fabs:
-      return true;
-    }
-  }
-
-  return false;
-}
-
-/// If \p SignBitOnly is true, test for a known 0 sign bit rather than a
-/// standard ordered compare. e.g. make -0.0 olt 0.0 be true because of the sign
-/// bit despite comparing equal.
-static bool cannotBeOrderedLessThanZeroImpl(const Value *V,
-                                            const TargetLibraryInfo *TLI,
-                                            bool SignBitOnly,
-                                            unsigned Depth) {
-  // TODO: This function does not do the right thing when SignBitOnly is true
-  // and we're lowering to a hypothetical IEEE 754-compliant-but-evil platform
-  // which flips the sign bits of NaNs.  See
-  // https://llvm.org/bugs/show_bug.cgi?id=31702.
-
-  if (const ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
-    return !CFP->getValueAPF().isNegative() ||
-           (!SignBitOnly && CFP->getValueAPF().isZero());
-  }
-
-  // Handle vector of constants.
-  if (auto *CV = dyn_cast<Constant>(V)) {
-    if (CV->getType()->isVectorTy()) {
-      unsigned NumElts = CV->getType()->getVectorNumElements();
-      for (unsigned i = 0; i != NumElts; ++i) {
-        auto *CFP = dyn_cast_or_null<ConstantFP>(CV->getAggregateElement(i));
-        if (!CFP)
-          return false;
-        if (CFP->getValueAPF().isNegative() &&
-            (SignBitOnly || !CFP->getValueAPF().isZero()))
-          return false;
-      }
-
-      // All non-negative ConstantFPs.
-      return true;
-    }
-  }
-
-  if (Depth == MaxDepth)
-    return false; // Limit search depth.
-
-  const Operator *I = dyn_cast<Operator>(V);
-  if (!I)
-    return false;
-
-  switch (I->getOpcode()) {
-  default:
-    break;
-  // Unsigned integers are always nonnegative.
-  case Instruction::UIToFP:
-    return true;
-  case Instruction::FMul:
-    // x*x is always non-negative or a NaN.
-    if (I->getOperand(0) == I->getOperand(1) &&
-        (!SignBitOnly || cast<FPMathOperator>(I)->hasNoNaNs()))
-      return true;
-
-    LLVM_FALLTHROUGH;
-  case Instruction::FAdd:
-  case Instruction::FDiv:
-  case Instruction::FRem:
-    return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                           Depth + 1) &&
-           cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly,
-                                           Depth + 1);
-  case Instruction::Select:
-    return cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly,
-                                           Depth + 1) &&
-           cannotBeOrderedLessThanZeroImpl(I->getOperand(2), TLI, SignBitOnly,
-                                           Depth + 1);
-  case Instruction::FPExt:
-  case Instruction::FPTrunc:
-    // Widening/narrowing never change sign.
-    return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                           Depth + 1);
-  case Instruction::ExtractElement:
-    // Look through extract element. At the moment we keep this simple and skip
-    // tracking the specific element. But at least we might find information
-    // valid for all elements of the vector.
-    return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                           Depth + 1);
-  case Instruction::Call:
-    const auto *CI = cast<CallInst>(I);
-    Intrinsic::ID IID = getIntrinsicForCallSite(CI, TLI);
-    switch (IID) {
-    default:
-      break;
-    case Intrinsic::maxnum:
-      return (isKnownNeverNaN(I->getOperand(0), TLI) &&
-              cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI,
-                                              SignBitOnly, Depth + 1)) ||
-            (isKnownNeverNaN(I->getOperand(1), TLI) &&
-              cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI,
-                                              SignBitOnly, Depth + 1));
-
-    case Intrinsic::maximum:
-      return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                             Depth + 1) ||
-             cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly,
-                                             Depth + 1);
-    case Intrinsic::minnum:
-    case Intrinsic::minimum:
-      return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                             Depth + 1) &&
-             cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly,
-                                             Depth + 1);
-    case Intrinsic::exp:
-    case Intrinsic::exp2:
-    case Intrinsic::fabs:
-      return true;
-
-    case Intrinsic::sqrt:
-      // sqrt(x) is always >= -0 or NaN.  Moreover, sqrt(x) == -0 iff x == -0.
-      if (!SignBitOnly)
-        return true;
-      return CI->hasNoNaNs() && (CI->hasNoSignedZeros() ||
-                                 CannotBeNegativeZero(CI->getOperand(0), TLI));
-
-    case Intrinsic::powi:
-      if (ConstantInt *Exponent = dyn_cast<ConstantInt>(I->getOperand(1))) {
-        // powi(x,n) is non-negative if n is even.
-        if (Exponent->getBitWidth() <= 64 && Exponent->getSExtValue() % 2u == 0)
-          return true;
-      }
-      // TODO: This is not correct.  Given that exp is an integer, here are the
-      // ways that pow can return a negative value:
-      //
-      //   pow(x, exp)    --> negative if exp is odd and x is negative.
-      //   pow(-0, exp)   --> -inf if exp is negative odd.
-      //   pow(-0, exp)   --> -0 if exp is positive odd.
-      //   pow(-inf, exp) --> -0 if exp is negative odd.
-      //   pow(-inf, exp) --> -inf if exp is positive odd.
-      //
-      // Therefore, if !SignBitOnly, we can return true if x >= +0 or x is NaN,
-      // but we must return false if x == -0.  Unfortunately we do not currently
-      // have a way of expressing this constraint.  See details in
-      // https://llvm.org/bugs/show_bug.cgi?id=31702.
-      return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly,
-                                             Depth + 1);
-
-    case Intrinsic::fma:
-    case Intrinsic::fmuladd:
-      // x*x+y is non-negative if y is non-negative.
-      return I->getOperand(0) == I->getOperand(1) &&
-             (!SignBitOnly || cast<FPMathOperator>(I)->hasNoNaNs()) &&
-             cannotBeOrderedLessThanZeroImpl(I->getOperand(2), TLI, SignBitOnly,
-                                             Depth + 1);
-    }
-    break;
-  }
-  return false;
-}
-
-bool llvm::CannotBeOrderedLessThanZero(const Value *V,
-                                       const TargetLibraryInfo *TLI) {
-  return cannotBeOrderedLessThanZeroImpl(V, TLI, false, 0);
-}
-
-bool llvm::SignBitMustBeZero(const Value *V, const TargetLibraryInfo *TLI) {
-  return cannotBeOrderedLessThanZeroImpl(V, TLI, true, 0);
-}
-
-bool llvm::isKnownNeverNaN(const Value *V, const TargetLibraryInfo *TLI,
-                           unsigned Depth) {
-  assert(V->getType()->isFPOrFPVectorTy() && "Querying for NaN on non-FP type");
-
-  // If we're told that NaNs won't happen, assume they won't.
-  if (auto *FPMathOp = dyn_cast<FPMathOperator>(V))
-    if (FPMathOp->hasNoNaNs())
-      return true;
-
-  // Handle scalar constants.
-  if (auto *CFP = dyn_cast<ConstantFP>(V))
-    return !CFP->isNaN();
-
-  if (Depth == MaxDepth)
-    return false;
-
-  if (auto *Inst = dyn_cast<Instruction>(V)) {
-    switch (Inst->getOpcode()) {
-    case Instruction::FAdd:
-    case Instruction::FMul:
-    case Instruction::FSub:
-    case Instruction::FDiv:
-    case Instruction::FRem: {
-      // TODO: Need isKnownNeverInfinity
-      return false;
-    }
-    case Instruction::Select: {
-      return isKnownNeverNaN(Inst->getOperand(1), TLI, Depth + 1) &&
-             isKnownNeverNaN(Inst->getOperand(2), TLI, Depth + 1);
-    }
-    case Instruction::SIToFP:
-    case Instruction::UIToFP:
-      return true;
-    case Instruction::FPTrunc:
-    case Instruction::FPExt:
-      return isKnownNeverNaN(Inst->getOperand(0), TLI, Depth + 1);
-    default:
-      break;
-    }
-  }
-
-  if (const auto *II = dyn_cast<IntrinsicInst>(V)) {
-    switch (II->getIntrinsicID()) {
-    case Intrinsic::canonicalize:
-    case Intrinsic::fabs:
-    case Intrinsic::copysign:
-    case Intrinsic::exp:
-    case Intrinsic::exp2:
-    case Intrinsic::floor:
-    case Intrinsic::ceil:
-    case Intrinsic::trunc:
-    case Intrinsic::rint:
-    case Intrinsic::nearbyint:
-    case Intrinsic::round:
-      return isKnownNeverNaN(II->getArgOperand(0), TLI, Depth + 1);
-    case Intrinsic::sqrt:
-      return isKnownNeverNaN(II->getArgOperand(0), TLI, Depth + 1) &&
-             CannotBeOrderedLessThanZero(II->getArgOperand(0), TLI);
-    default:
-      return false;
-    }
-  }
-
-  // Bail out for constant expressions, but try to handle vector constants.
-  if (!V->getType()->isVectorTy() || !isa<Constant>(V))
-    return false;
-
-  // For vectors, verify that each element is not NaN.
-  unsigned NumElts = V->getType()->getVectorNumElements();
-  for (unsigned i = 0; i != NumElts; ++i) {
-    Constant *Elt = cast<Constant>(V)->getAggregateElement(i);
-    if (!Elt)
-      return false;
-    if (isa<UndefValue>(Elt))
-      continue;
-    auto *CElt = dyn_cast<ConstantFP>(Elt);
-    if (!CElt || CElt->isNaN())
-      return false;
-  }
-  // All elements were confirmed not-NaN or undefined.
-  return true;
-}
-
-Value *llvm::isBytewiseValue(Value *V) {
-
-  // All byte-wide stores are splatable, even of arbitrary variables.
-  if (V->getType()->isIntegerTy(8))
-    return V;
-
-  LLVMContext &Ctx = V->getContext();
-
-  // Undef don't care.
-  auto *UndefInt8 = UndefValue::get(Type::getInt8Ty(Ctx));
-  if (isa<UndefValue>(V))
-    return UndefInt8;
-
-  Constant *C = dyn_cast<Constant>(V);
-  if (!C) {
-    // Conceptually, we could handle things like:
-    //   %a = zext i8 %X to i16
-    //   %b = shl i16 %a, 8
-    //   %c = or i16 %a, %b
-    // but until there is an example that actually needs this, it doesn't seem
-    // worth worrying about.
-    return nullptr;
-  }
-
-  // Handle 'null' ConstantArrayZero etc.
-  if (C->isNullValue())
-    return Constant::getNullValue(Type::getInt8Ty(Ctx));
-
-  // Constant floating-point values can be handled as integer values if the
-  // corresponding integer value is "byteable".  An important case is 0.0.
-  if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
-    Type *Ty = nullptr;
-    if (CFP->getType()->isHalfTy())
-      Ty = Type::getInt16Ty(Ctx);
-    else if (CFP->getType()->isFloatTy())
-      Ty = Type::getInt32Ty(Ctx);
-    else if (CFP->getType()->isDoubleTy())
-      Ty = Type::getInt64Ty(Ctx);
-    // Don't handle long double formats, which have strange constraints.
-    return Ty ? isBytewiseValue(ConstantExpr::getBitCast(CFP, Ty)) : nullptr;
-  }
-
-  // We can handle constant integers that are multiple of 8 bits.
-  if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) {
-    if (CI->getBitWidth() % 8 == 0) {
-      assert(CI->getBitWidth() > 8 && "8 bits should be handled above!");
-      if (!CI->getValue().isSplat(8))
-        return nullptr;
-      return ConstantInt::get(Ctx, CI->getValue().trunc(8));
-    }
-  }
-
-  auto Merge = [&](Value *LHS, Value *RHS) -> Value * {
-    if (LHS == RHS)
-      return LHS;
-    if (!LHS || !RHS)
-      return nullptr;
-    if (LHS == UndefInt8)
-      return RHS;
-    if (RHS == UndefInt8)
-      return LHS;
-    return nullptr;
-  };
-
-  if (ConstantDataSequential *CA = dyn_cast<ConstantDataSequential>(C)) {
-    Value *Val = UndefInt8;
-    for (unsigned I = 0, E = CA->getNumElements(); I != E; ++I)
-      if (!(Val = Merge(Val, isBytewiseValue(CA->getElementAsConstant(I)))))
-        return nullptr;
-    return Val;
-  }
-
-  if (isa<ConstantVector>(C)) {
-    Constant *Splat = cast<ConstantVector>(C)->getSplatValue();
-    return Splat ? isBytewiseValue(Splat) : nullptr;
-  }
-
-  if (isa<ConstantArray>(C) || isa<ConstantStruct>(C)) {
-    Value *Val = UndefInt8;
-    for (unsigned I = 0, E = C->getNumOperands(); I != E; ++I)
-      if (!(Val = Merge(Val, isBytewiseValue(C->getOperand(I)))))
-        return nullptr;
-    return Val;
-  }
-
-  // Don't try to handle the handful of other constants.
-  return nullptr;
-}
-
-// This is the recursive version of BuildSubAggregate. It takes a few different
-// arguments. Idxs is the index within the nested struct From that we are
-// looking at now (which is of type IndexedType). IdxSkip is the number of
-// indices from Idxs that should be left out when inserting into the resulting
-// struct. To is the result struct built so far, new insertvalue instructions
-// build on that.
-static Value *BuildSubAggregate(Value *From, Value* To, Type *IndexedType,
-                                SmallVectorImpl<unsigned> &Idxs,
-                                unsigned IdxSkip,
-                                Instruction *InsertBefore) {
-  StructType *STy = dyn_cast<StructType>(IndexedType);
-  if (STy) {
-    // Save the original To argument so we can modify it
-    Value *OrigTo = To;
-    // General case, the type indexed by Idxs is a struct
-    for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
-      // Process each struct element recursively
-      Idxs.push_back(i);
-      Value *PrevTo = To;
-      To = BuildSubAggregate(From, To, STy->getElementType(i), Idxs, IdxSkip,
-                             InsertBefore);
-      Idxs.pop_back();
-      if (!To) {
-        // Couldn't find any inserted value for this index? Cleanup
-        while (PrevTo != OrigTo) {
-          InsertValueInst* Del = cast<InsertValueInst>(PrevTo);
-          PrevTo = Del->getAggregateOperand();
-          Del->eraseFromParent();
-        }
-        // Stop processing elements
-        break;
-      }
-    }
-    // If we successfully found a value for each of our subaggregates
-    if (To)
-      return To;
-  }
-  // Base case, the type indexed by SourceIdxs is not a struct, or not all of
-  // the struct's elements had a value that was inserted directly. In the latter
-  // case, perhaps we can't determine each of the subelements individually, but
-  // we might be able to find the complete struct somewhere.
-
-  // Find the value that is at that particular spot
-  Value *V = FindInsertedValue(From, Idxs);
-
-  if (!V)
-    return nullptr;
-
-  // Insert the value in the new (sub) aggregate
-  return InsertValueInst::Create(To, V, makeArrayRef(Idxs).slice(IdxSkip),
-                                 "tmp", InsertBefore);
-}
-
-// This helper takes a nested struct and extracts a part of it (which is again a
-// struct) into a new value. For example, given the struct:
-// { a, { b, { c, d }, e } }
-// and the indices "1, 1" this returns
-// { c, d }.
-//
-// It does this by inserting an insertvalue for each element in the resulting
-// struct, as opposed to just inserting a single struct. This will only work if
-// each of the elements of the substruct are known (ie, inserted into From by an
-// insertvalue instruction somewhere).
-//
-// All inserted insertvalue instructions are inserted before InsertBefore
-static Value *BuildSubAggregate(Value *From, ArrayRef<unsigned> idx_range,
-                                Instruction *InsertBefore) {
-  assert(InsertBefore && "Must have someplace to insert!");
-  Type *IndexedType = ExtractValueInst::getIndexedType(From->getType(),
-                                                             idx_range);
-  Value *To = UndefValue::get(IndexedType);
-  SmallVector<unsigned, 10> Idxs(idx_range.begin(), idx_range.end());
-  unsigned IdxSkip = Idxs.size();
-
-  return BuildSubAggregate(From, To, IndexedType, Idxs, IdxSkip, InsertBefore);
-}
-
-/// Given an aggregate and a sequence of indices, see if the scalar value
-/// indexed is already around as a register, for example if it was inserted
-/// directly into the aggregate.
-///
-/// If InsertBefore is not null, this function will duplicate (modified)
-/// insertvalues when a part of a nested struct is extracted.
-Value *llvm::FindInsertedValue(Value *V, ArrayRef<unsigned> idx_range,
-                               Instruction *InsertBefore) {
-  // Nothing to index? Just return V then (this is useful at the end of our
-  // recursion).
-  if (idx_range.empty())
-    return V;
-  // We have indices, so V should have an indexable type.
-  assert((V->getType()->isStructTy() || V->getType()->isArrayTy()) &&
-         "Not looking at a struct or array?");
-  assert(ExtractValueInst::getIndexedType(V->getType(), idx_range) &&
-         "Invalid indices for type?");
-
-  if (Constant *C = dyn_cast<Constant>(V)) {
-    C = C->getAggregateElement(idx_range[0]);
-    if (!C) return nullptr;
-    return FindInsertedValue(C, idx_range.slice(1), InsertBefore);
-  }
-
-  if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) {
-    // Loop the indices for the insertvalue instruction in parallel with the
-    // requested indices
-    const unsigned *req_idx = idx_range.begin();
-    for (const unsigned *i = I->idx_begin(), *e = I->idx_end();
-         i != e; ++i, ++req_idx) {
-      if (req_idx == idx_range.end()) {
-        // We can't handle this without inserting insertvalues
-        if (!InsertBefore)
-          return nullptr;
-
-        // The requested index identifies a part of a nested aggregate. Handle
-        // this specially. For example,
-        // %A = insertvalue { i32, {i32, i32 } } undef, i32 10, 1, 0
-        // %B = insertvalue { i32, {i32, i32 } } %A, i32 11, 1, 1
-        // %C = extractvalue {i32, { i32, i32 } } %B, 1
-        // This can be changed into
-        // %A = insertvalue {i32, i32 } undef, i32 10, 0
-        // %C = insertvalue {i32, i32 } %A, i32 11, 1
-        // which allows the unused 0,0 element from the nested struct to be
-        // removed.
-        return BuildSubAggregate(V, makeArrayRef(idx_range.begin(), req_idx),
-                                 InsertBefore);
-      }
-
-      // This insert value inserts something else than what we are looking for.
-      // See if the (aggregate) value inserted into has the value we are
-      // looking for, then.
-      if (*req_idx != *i)
-        return FindInsertedValue(I->getAggregateOperand(), idx_range,
-                                 InsertBefore);
-    }
-    // If we end up here, the indices of the insertvalue match with those
-    // requested (though possibly only partially). Now we recursively look at
-    // the inserted value, passing any remaining indices.
-    return FindInsertedValue(I->getInsertedValueOperand(),
-                             makeArrayRef(req_idx, idx_range.end()),
-                             InsertBefore);
-  }
-
-  if (ExtractValueInst *I = dyn_cast<ExtractValueInst>(V)) {
-    // If we're extracting a value from an aggregate that was extracted from
-    // something else, we can extract from that something else directly instead.
-    // However, we will need to chain I's indices with the requested indices.
-
-    // Calculate the number of indices required
-    unsigned size = I->getNumIndices() + idx_range.size();
-    // Allocate some space to put the new indices in
-    SmallVector<unsigned, 5> Idxs;
-    Idxs.reserve(size);
-    // Add indices from the extract value instruction
-    Idxs.append(I->idx_begin(), I->idx_end());
-
-    // Add requested indices
-    Idxs.append(idx_range.begin(), idx_range.end());
-
-    assert(Idxs.size() == size
-           && "Number of indices added not correct?");
-
-    return FindInsertedValue(I->getAggregateOperand(), Idxs, InsertBefore);
-  }
-  // Otherwise, we don't know (such as, extracting from a function return value
-  // or load instruction)
-  return nullptr;
-}
-
-/// Analyze the specified pointer to see if it can be expressed as a base
-/// pointer plus a constant offset. Return the base and offset to the caller.
-Value *llvm::GetPointerBaseWithConstantOffset(Value *Ptr, int64_t &Offset,
-                                              const DataLayout &DL) {
-  unsigned BitWidth = DL.getIndexTypeSizeInBits(Ptr->getType());
-  APInt ByteOffset(BitWidth, 0);
-
-  // We walk up the defs but use a visited set to handle unreachable code. In
-  // that case, we stop after accumulating the cycle once (not that it
-  // matters).
-  SmallPtrSet<Value *, 16> Visited;
-  while (Visited.insert(Ptr).second) {
-    if (Ptr->getType()->isVectorTy())
-      break;
-
-    if (GEPOperator *GEP = dyn_cast<GEPOperator>(Ptr)) {
-      // If one of the values we have visited is an addrspacecast, then
-      // the pointer type of this GEP may be different from the type
-      // of the Ptr parameter which was passed to this function.  This
-      // means when we construct GEPOffset, we need to use the size
-      // of GEP's pointer type rather than the size of the original
-      // pointer type.
-      APInt GEPOffset(DL.getIndexTypeSizeInBits(Ptr->getType()), 0);
-      if (!GEP->accumulateConstantOffset(DL, GEPOffset))
-        break;
-
-      APInt OrigByteOffset(ByteOffset);
-      ByteOffset += GEPOffset.sextOrTrunc(ByteOffset.getBitWidth());
-      if (ByteOffset.getMinSignedBits() > 64) {
-        // Stop traversal if the pointer offset wouldn't fit into int64_t
-        // (this should be removed if Offset is updated to an APInt)
-        ByteOffset = OrigByteOffset;
-        break;
-      }
-
-      Ptr = GEP->getPointerOperand();
-    } else if (Operator::getOpcode(Ptr) == Instruction::BitCast ||
-               Operator::getOpcode(Ptr) == Instruction::AddrSpaceCast) {
-      Ptr = cast<Operator>(Ptr)->getOperand(0);
-    } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(Ptr)) {
-      if (GA->isInterposable())
-        break;
-      Ptr = GA->getAliasee();
-    } else {
-      break;
-    }
-  }
-  Offset = ByteOffset.getSExtValue();
-  return Ptr;
-}
-
-bool llvm::isGEPBasedOnPointerToString(const GEPOperator *GEP,
-                                       unsigned CharSize) {
-  // Make sure the GEP has exactly three arguments.
-  if (GEP->getNumOperands() != 3)
-    return false;
-
-  // Make sure the index-ee is a pointer to array of \p CharSize integers.
-  // CharSize.
-  ArrayType *AT = dyn_cast<ArrayType>(GEP->getSourceElementType());
-  if (!AT || !AT->getElementType()->isIntegerTy(CharSize))
-    return false;
-
-  // Check to make sure that the first operand of the GEP is an integer and
-  // has value 0 so that we are sure we're indexing into the initializer.
-  const ConstantInt *FirstIdx = dyn_cast<ConstantInt>(GEP->getOperand(1));
-  if (!FirstIdx || !FirstIdx->isZero())
-    return false;
-
-  return true;
-}
-
-bool llvm::getConstantDataArrayInfo(const Value *V,
-                                    ConstantDataArraySlice &Slice,
-                                    unsigned ElementSize, uint64_t Offset) {
-  assert(V);
-
-  // Look through bitcast instructions and geps.
-  V = V->stripPointerCasts();
-
-  // If the value is a GEP instruction or constant expression, treat it as an
-  // offset.
-  if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
-    // The GEP operator should be based on a pointer to string constant, and is
-    // indexing into the string constant.
-    if (!isGEPBasedOnPointerToString(GEP, ElementSize))
-      return false;
-
-    // If the second index isn't a ConstantInt, then this is a variable index
-    // into the array.  If this occurs, we can't say anything meaningful about
-    // the string.
-    uint64_t StartIdx = 0;
-    if (const ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(2)))
-      StartIdx = CI->getZExtValue();
-    else
-      return false;
-    return getConstantDataArrayInfo(GEP->getOperand(0), Slice, ElementSize,
-                                    StartIdx + Offset);
-  }
-
-  // The GEP instruction, constant or instruction, must reference a global
-  // variable that is a constant and is initialized. The referenced constant
-  // initializer is the array that we'll use for optimization.
-  const GlobalVariable *GV = dyn_cast<GlobalVariable>(V);
-  if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer())
-    return false;
-
-  const ConstantDataArray *Array;
-  ArrayType *ArrayTy;
-  if (GV->getInitializer()->isNullValue()) {
-    Type *GVTy = GV->getValueType();
-    if ( (ArrayTy = dyn_cast<ArrayType>(GVTy)) ) {
-      // A zeroinitializer for the array; there is no ConstantDataArray.
-      Array = nullptr;
-    } else {
-      const DataLayout &DL = GV->getParent()->getDataLayout();
-      uint64_t SizeInBytes = DL.getTypeStoreSize(GVTy);
-      uint64_t Length = SizeInBytes / (ElementSize / 8);
-      if (Length <= Offset)
-        return false;
-
-      Slice.Array = nullptr;
-      Slice.Offset = 0;
-      Slice.Length = Length - Offset;
-      return true;
-    }
-  } else {
-    // This must be a ConstantDataArray.
-    Array = dyn_cast<ConstantDataArray>(GV->getInitializer());
-    if (!Array)
-      return false;
-    ArrayTy = Array->getType();
-  }
-  if (!ArrayTy->getElementType()->isIntegerTy(ElementSize))
-    return false;
-
-  uint64_t NumElts = ArrayTy->getArrayNumElements();
-  if (Offset > NumElts)
-    return false;
-
-  Slice.Array = Array;
-  Slice.Offset = Offset;
-  Slice.Length = NumElts - Offset;
-  return true;
-}
-
-/// This function computes the length of a null-terminated C string pointed to
-/// by V. If successful, it returns true and returns the string in Str.
-/// If unsuccessful, it returns false.
-bool llvm::getConstantStringInfo(const Value *V, StringRef &Str,
-                                 uint64_t Offset, bool TrimAtNul) {
-  ConstantDataArraySlice Slice;
-  if (!getConstantDataArrayInfo(V, Slice, 8, Offset))
-    return false;
-
-  if (Slice.Array == nullptr) {
-    if (TrimAtNul) {
-      Str = StringRef();
-      return true;
-    }
-    if (Slice.Length == 1) {
-      Str = StringRef("", 1);
-      return true;
-    }
-    // We cannot instantiate a StringRef as we do not have an appropriate string
-    // of 0s at hand.
-    return false;
-  }
-
-  // Start out with the entire array in the StringRef.
-  Str = Slice.Array->getAsString();
-  // Skip over 'offset' bytes.
-  Str = Str.substr(Slice.Offset);
-
-  if (TrimAtNul) {
-    // Trim off the \0 and anything after it.  If the array is not nul
-    // terminated, we just return the whole end of string.  The client may know
-    // some other way that the string is length-bound.
-    Str = Str.substr(0, Str.find('\0'));
-  }
-  return true;
-}
-
-// These next two are very similar to the above, but also look through PHI
-// nodes.
-// TODO: See if we can integrate these two together.
-
-/// If we can compute the length of the string pointed to by
-/// the specified pointer, return 'len+1'.  If we can't, return 0.
-static uint64_t GetStringLengthH(const Value *V,
-                                 SmallPtrSetImpl<const PHINode*> &PHIs,
-                                 unsigned CharSize) {
-  // Look through noop bitcast instructions.
-  V = V->stripPointerCasts();
-
-  // If this is a PHI node, there are two cases: either we have already seen it
-  // or we haven't.
-  if (const PHINode *PN = dyn_cast<PHINode>(V)) {
-    if (!PHIs.insert(PN).second)
-      return ~0ULL;  // already in the set.
-
-    // If it was new, see if all the input strings are the same length.
-    uint64_t LenSoFar = ~0ULL;
-    for (Value *IncValue : PN->incoming_values()) {
-      uint64_t Len = GetStringLengthH(IncValue, PHIs, CharSize);
-      if (Len == 0) return 0; // Unknown length -> unknown.
-
-      if (Len == ~0ULL) continue;
-
-      if (Len != LenSoFar && LenSoFar != ~0ULL)
-        return 0;    // Disagree -> unknown.
-      LenSoFar = Len;
-    }
-
-    // Success, all agree.
-    return LenSoFar;
-  }
-
-  // strlen(select(c,x,y)) -> strlen(x) ^ strlen(y)
-  if (const SelectInst *SI = dyn_cast<SelectInst>(V)) {
-    uint64_t Len1 = GetStringLengthH(SI->getTrueValue(), PHIs, CharSize);
-    if (Len1 == 0) return 0;
-    uint64_t Len2 = GetStringLengthH(SI->getFalseValue(), PHIs, CharSize);
-    if (Len2 == 0) return 0;
-    if (Len1 == ~0ULL) return Len2;
-    if (Len2 == ~0ULL) return Len1;
-    if (Len1 != Len2) return 0;
-    return Len1;
-  }
-
-  // Otherwise, see if we can read the string.
-  ConstantDataArraySlice Slice;
-  if (!getConstantDataArrayInfo(V, Slice, CharSize))
-    return 0;
-
-  if (Slice.Array == nullptr)
-    return 1;
-
-  // Search for nul characters
-  unsigned NullIndex = 0;
-  for (unsigned E = Slice.Length; NullIndex < E; ++NullIndex) {
-    if (Slice.Array->getElementAsInteger(Slice.Offset + NullIndex) == 0)
-      break;
-  }
-
-  return NullIndex + 1;
-}
-
-/// If we can compute the length of the string pointed to by
-/// the specified pointer, return 'len+1'.  If we can't, return 0.
-uint64_t llvm::GetStringLength(const Value *V, unsigned CharSize) {
-  if (!V->getType()->isPointerTy())
-    return 0;
-
-  SmallPtrSet<const PHINode*, 32> PHIs;
-  uint64_t Len = GetStringLengthH(V, PHIs, CharSize);
-  // If Len is ~0ULL, we had an infinite phi cycle: this is dead code, so return
-  // an empty string as a length.
-  return Len == ~0ULL ? 1 : Len;
-}
-
-const Value *llvm::getArgumentAliasingToReturnedPointer(const CallBase *Call) {
-  assert(Call &&
-         "getArgumentAliasingToReturnedPointer only works on nonnull calls");
-  if (const Value *RV = Call->getReturnedArgOperand())
-    return RV;
-  // This can be used only as a aliasing property.
-  if (isIntrinsicReturningPointerAliasingArgumentWithoutCapturing(Call))
-    return Call->getArgOperand(0);
-  return nullptr;
-}
-
-bool llvm::isIntrinsicReturningPointerAliasingArgumentWithoutCapturing(
-    const CallBase *Call) {
-  return Call->getIntrinsicID() == Intrinsic::launder_invariant_group ||
-         Call->getIntrinsicID() == Intrinsic::strip_invariant_group;
-}
-
-/// \p PN defines a loop-variant pointer to an object.  Check if the
-/// previous iteration of the loop was referring to the same object as \p PN.
-static bool isSameUnderlyingObjectInLoop(const PHINode *PN,
-                                         const LoopInfo *LI) {
-  // Find the loop-defined value.
-  Loop *L = LI->getLoopFor(PN->getParent());
-  if (PN->getNumIncomingValues() != 2)
-    return true;
-
-  // Find the value from previous iteration.
-  auto *PrevValue = dyn_cast<Instruction>(PN->getIncomingValue(0));
-  if (!PrevValue || LI->getLoopFor(PrevValue->getParent()) != L)
-    PrevValue = dyn_cast<Instruction>(PN->getIncomingValue(1));
-  if (!PrevValue || LI->getLoopFor(PrevValue->getParent()) != L)
-    return true;
-
-  // If a new pointer is loaded in the loop, the pointer references a different
-  // object in every iteration.  E.g.:
-  //    for (i)
-  //       int *p = a[i];
-  //       ...
-  if (auto *Load = dyn_cast<LoadInst>(PrevValue))
-    if (!L->isLoopInvariant(Load->getPointerOperand()))
-      return false;
-  return true;
-}
-
-Value *llvm::GetUnderlyingObject(Value *V, const DataLayout &DL,
-                                 unsigned MaxLookup) {
-  if (!V->getType()->isPointerTy())
-    return V;
-  for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
-    if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
-      V = GEP->getPointerOperand();
-    } else if (Operator::getOpcode(V) == Instruction::BitCast ||
-               Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
-      V = cast<Operator>(V)->getOperand(0);
-    } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
-      if (GA->isInterposable())
-        return V;
-      V = GA->getAliasee();
-    } else if (isa<AllocaInst>(V)) {
-      // An alloca can't be further simplified.
-      return V;
-    } else {
-      if (auto *Call = dyn_cast<CallBase>(V)) {
-        // CaptureTracking can know about special capturing properties of some
-        // intrinsics like launder.invariant.group, that can't be expressed with
-        // the attributes, but have properties like returning aliasing pointer.
-        // Because some analysis may assume that nocaptured pointer is not
-        // returned from some special intrinsic (because function would have to
-        // be marked with returns attribute), it is crucial to use this function
-        // because it should be in sync with CaptureTracking. Not using it may
-        // cause weird miscompilations where 2 aliasing pointers are assumed to
-        // noalias.
-        if (auto *RP = getArgumentAliasingToReturnedPointer(Call)) {
-          V = RP;
-          continue;
-        }
-      }
-
-      // See if InstructionSimplify knows any relevant tricks.
-      if (Instruction *I = dyn_cast<Instruction>(V))
-        // TODO: Acquire a DominatorTree and AssumptionCache and use them.
-        if (Value *Simplified = SimplifyInstruction(I, {DL, I})) {
-          V = Simplified;
-          continue;
-        }
-
-      return V;
-    }
-    assert(V->getType()->isPointerTy() && "Unexpected operand type!");
-  }
-  return V;
-}
-
-void llvm::GetUnderlyingObjects(Value *V, SmallVectorImpl<Value *> &Objects,
-                                const DataLayout &DL, LoopInfo *LI,
-                                unsigned MaxLookup) {
-  SmallPtrSet<Value *, 4> Visited;
-  SmallVector<Value *, 4> Worklist;
-  Worklist.push_back(V);
-  do {
-    Value *P = Worklist.pop_back_val();
-    P = GetUnderlyingObject(P, DL, MaxLookup);
-
-    if (!Visited.insert(P).second)
-      continue;
-
-    if (SelectInst *SI = dyn_cast<SelectInst>(P)) {
-      Worklist.push_back(SI->getTrueValue());
-      Worklist.push_back(SI->getFalseValue());
-      continue;
-    }
-
-    if (PHINode *PN = dyn_cast<PHINode>(P)) {
-      // If this PHI changes the underlying object in every iteration of the
-      // loop, don't look through it.  Consider:
-      //   int **A;
-      //   for (i) {
-      //     Prev = Curr;     // Prev = PHI (Prev_0, Curr)
-      //     Curr = A[i];
-      //     *Prev, *Curr;
-      //
-      // Prev is tracking Curr one iteration behind so they refer to different
-      // underlying objects.
-      if (!LI || !LI->isLoopHeader(PN->getParent()) ||
-          isSameUnderlyingObjectInLoop(PN, LI))
-        for (Value *IncValue : PN->incoming_values())
-          Worklist.push_back(IncValue);
-      continue;
-    }
-
-    Objects.push_back(P);
-  } while (!Worklist.empty());
-}
-
-/// This is the function that does the work of looking through basic
-/// ptrtoint+arithmetic+inttoptr sequences.
-static const Value *getUnderlyingObjectFromInt(const Value *V) {
-  do {
-    if (const Operator *U = dyn_cast<Operator>(V)) {
-      // If we find a ptrtoint, we can transfer control back to the
-      // regular getUnderlyingObjectFromInt.
-      if (U->getOpcode() == Instruction::PtrToInt)
-        return U->getOperand(0);
-      // If we find an add of a constant, a multiplied value, or a phi, it's
-      // likely that the other operand will lead us to the base
-      // object. We don't have to worry about the case where the
-      // object address is somehow being computed by the multiply,
-      // because our callers only care when the result is an
-      // identifiable object.
-      if (U->getOpcode() != Instruction::Add ||
-          (!isa<ConstantInt>(U->getOperand(1)) &&
-           Operator::getOpcode(U->getOperand(1)) != Instruction::Mul &&
-           !isa<PHINode>(U->getOperand(1))))
-        return V;
-      V = U->getOperand(0);
-    } else {
-      return V;
-    }
-    assert(V->getType()->isIntegerTy() && "Unexpected operand type!");
-  } while (true);
-}
-
-/// This is a wrapper around GetUnderlyingObjects and adds support for basic
-/// ptrtoint+arithmetic+inttoptr sequences.
-/// It returns false if unidentified object is found in GetUnderlyingObjects.
-bool llvm::getUnderlyingObjectsForCodeGen(const Value *V,
-                          SmallVectorImpl<Value *> &Objects,
-                          const DataLayout &DL) {
-  SmallPtrSet<const Value *, 16> Visited;
-  SmallVector<const Value *, 4> Working(1, V);
-  do {
-    V = Working.pop_back_val();
-
-    SmallVector<Value *, 4> Objs;
-    GetUnderlyingObjects(const_cast<Value *>(V), Objs, DL);
-
-    for (Value *V : Objs) {
-      if (!Visited.insert(V).second)
-        continue;
-      if (Operator::getOpcode(V) == Instruction::IntToPtr) {
-        const Value *O =
-          getUnderlyingObjectFromInt(cast<User>(V)->getOperand(0));
-        if (O->getType()->isPointerTy()) {
-          Working.push_back(O);
-          continue;
-        }
-      }
-      // If GetUnderlyingObjects fails to find an identifiable object,
-      // getUnderlyingObjectsForCodeGen also fails for safety.
-      if (!isIdentifiedObject(V)) {
-        Objects.clear();
-        return false;
-      }
-      Objects.push_back(const_cast<Value *>(V));
-    }
-  } while (!Working.empty());
-  return true;
-}
-
-/// Return true if the only users of this pointer are lifetime markers.
-bool llvm::onlyUsedByLifetimeMarkers(const Value *V) {
-  for (const User *U : V->users()) {
-    const IntrinsicInst *II = dyn_cast<IntrinsicInst>(U);
-    if (!II) return false;
-
-    if (!II->isLifetimeStartOrEnd())
-      return false;
-  }
-  return true;
-}
-
-bool llvm::isSafeToSpeculativelyExecute(const Value *V,
-                                        const Instruction *CtxI,
-                                        const DominatorTree *DT) {
-  const Operator *Inst = dyn_cast<Operator>(V);
-  if (!Inst)
-    return false;
-
-  for (unsigned i = 0, e = Inst->getNumOperands(); i != e; ++i)
-    if (Constant *C = dyn_cast<Constant>(Inst->getOperand(i)))
-      if (C->canTrap())
-        return false;
-
-  switch (Inst->getOpcode()) {
-  default:
-    return true;
-  case Instruction::UDiv:
-  case Instruction::URem: {
-    // x / y is undefined if y == 0.
-    const APInt *V;
-    if (match(Inst->getOperand(1), m_APInt(V)))
-      return *V != 0;
-    return false;
-  }
-  case Instruction::SDiv:
-  case Instruction::SRem: {
-    // x / y is undefined if y == 0 or x == INT_MIN and y == -1
-    const APInt *Numerator, *Denominator;
-    if (!match(Inst->getOperand(1), m_APInt(Denominator)))
-      return false;
-    // We cannot hoist this division if the denominator is 0.
-    if (*Denominator == 0)
-      return false;
-    // It's safe to hoist if the denominator is not 0 or -1.
-    if (*Denominator != -1)
-      return true;
-    // At this point we know that the denominator is -1.  It is safe to hoist as
-    // long we know that the numerator is not INT_MIN.
-    if (match(Inst->getOperand(0), m_APInt(Numerator)))
-      return !Numerator->isMinSignedValue();
-    // The numerator *might* be MinSignedValue.
-    return false;
-  }
-  case Instruction::Load: {
-    const LoadInst *LI = cast<LoadInst>(Inst);
-    if (!LI->isUnordered() ||
-        // Speculative load may create a race that did not exist in the source.
-        LI->getFunction()->hasFnAttribute(Attribute::SanitizeThread) ||
-        // Speculative load may load data from dirty regions.
-        LI->getFunction()->hasFnAttribute(Attribute::SanitizeAddress) ||
-        LI->getFunction()->hasFnAttribute(Attribute::SanitizeHWAddress))
-      return false;
-    const DataLayout &DL = LI->getModule()->getDataLayout();
-    return isDereferenceableAndAlignedPointer(LI->getPointerOperand(),
-                                              LI->getAlignment(), DL, CtxI, DT);
-  }
-  case Instruction::Call: {
-    auto *CI = cast<const CallInst>(Inst);
-    const Function *Callee = CI->getCalledFunction();
-
-    // The called function could have undefined behavior or side-effects, even
-    // if marked readnone nounwind.
-    return Callee && Callee->isSpeculatable();
-  }
-  case Instruction::VAArg:
-  case Instruction::Alloca:
-  case Instruction::Invoke:
-  case Instruction::PHI:
-  case Instruction::Store:
-  case Instruction::Ret:
-  case Instruction::Br:
-  case Instruction::IndirectBr:
-  case Instruction::Switch:
-  case Instruction::Unreachable:
-  case Instruction::Fence:
-  case Instruction::AtomicRMW:
-  case Instruction::AtomicCmpXchg:
-  case Instruction::LandingPad:
-  case Instruction::Resume:
-  case Instruction::CatchSwitch:
-  case Instruction::CatchPad:
-  case Instruction::CatchRet:
-  case Instruction::CleanupPad:
-  case Instruction::CleanupRet:
-    return false; // Misc instructions which have effects
-  }
-}
-
-bool llvm::mayBeMemoryDependent(const Instruction &I) {
-  return I.mayReadOrWriteMemory() || !isSafeToSpeculativelyExecute(&I);
-}
-
-OverflowResult llvm::computeOverflowForUnsignedMul(
-    const Value *LHS, const Value *RHS, const DataLayout &DL,
-    AssumptionCache *AC, const Instruction *CxtI, const DominatorTree *DT,
-    bool UseInstrInfo) {
-  // Multiplying n * m significant bits yields a result of n + m significant
-  // bits. If the total number of significant bits does not exceed the
-  // result bit width (minus 1), there is no overflow.
-  // This means if we have enough leading zero bits in the operands
-  // we can guarantee that the result does not overflow.
-  // Ref: "Hacker's Delight" by Henry Warren
-  unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
-  KnownBits LHSKnown(BitWidth);
-  KnownBits RHSKnown(BitWidth);
-  computeKnownBits(LHS, LHSKnown, DL, /*Depth=*/0, AC, CxtI, DT, nullptr,
-                   UseInstrInfo);
-  computeKnownBits(RHS, RHSKnown, DL, /*Depth=*/0, AC, CxtI, DT, nullptr,
-                   UseInstrInfo);
-  // Note that underestimating the number of zero bits gives a more
-  // conservative answer.
-  unsigned ZeroBits = LHSKnown.countMinLeadingZeros() +
-                      RHSKnown.countMinLeadingZeros();
-  // First handle the easy case: if we have enough zero bits there's
-  // definitely no overflow.
-  if (ZeroBits >= BitWidth)
-    return OverflowResult::NeverOverflows;
-
-  // Get the largest possible values for each operand.
-  APInt LHSMax = ~LHSKnown.Zero;
-  APInt RHSMax = ~RHSKnown.Zero;
-
-  // We know the multiply operation doesn't overflow if the maximum values for
-  // each operand will not overflow after we multiply them together.
-  bool MaxOverflow;
-  (void)LHSMax.umul_ov(RHSMax, MaxOverflow);
-  if (!MaxOverflow)
-    return OverflowResult::NeverOverflows;
-
-  // We know it always overflows if multiplying the smallest possible values for
-  // the operands also results in overflow.
-  bool MinOverflow;
-  (void)LHSKnown.One.umul_ov(RHSKnown.One, MinOverflow);
-  if (MinOverflow)
-    return OverflowResult::AlwaysOverflows;
-
-  return OverflowResult::MayOverflow;
-}
-
-OverflowResult
-llvm::computeOverflowForSignedMul(const Value *LHS, const Value *RHS,
-                                  const DataLayout &DL, AssumptionCache *AC,
-                                  const Instruction *CxtI,
-                                  const DominatorTree *DT, bool UseInstrInfo) {
-  // Multiplying n * m significant bits yields a result of n + m significant
-  // bits. If the total number of significant bits does not exceed the
-  // result bit width (minus 1), there is no overflow.
-  // This means if we have enough leading sign bits in the operands
-  // we can guarantee that the result does not overflow.
-  // Ref: "Hacker's Delight" by Henry Warren
-  unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
-
-  // Note that underestimating the number of sign bits gives a more
-  // conservative answer.
-  unsigned SignBits = ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) +
-                      ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT);
-
-  // First handle the easy case: if we have enough sign bits there's
-  // definitely no overflow.
-  if (SignBits > BitWidth + 1)
-    return OverflowResult::NeverOverflows;
-
-  // There are two ambiguous cases where there can be no overflow:
-  //   SignBits == BitWidth + 1    and
-  //   SignBits == BitWidth
-  // The second case is difficult to check, therefore we only handle the
-  // first case.
-  if (SignBits == BitWidth + 1) {
-    // It overflows only when both arguments are negative and the true
-    // product is exactly the minimum negative number.
-    // E.g. mul i16 with 17 sign bits: 0xff00 * 0xff80 = 0x8000
-    // For simplicity we just check if at least one side is not negative.
-    KnownBits LHSKnown = computeKnownBits(LHS, DL, /*Depth=*/0, AC, CxtI, DT,
-                                          nullptr, UseInstrInfo);
-    KnownBits RHSKnown = computeKnownBits(RHS, DL, /*Depth=*/0, AC, CxtI, DT,
-                                          nullptr, UseInstrInfo);
-    if (LHSKnown.isNonNegative() || RHSKnown.isNonNegative())
-      return OverflowResult::NeverOverflows;
-  }
-  return OverflowResult::MayOverflow;
-}
-
-OverflowResult llvm::computeOverflowForUnsignedAdd(
-    const Value *LHS, const Value *RHS, const DataLayout &DL,
-    AssumptionCache *AC, const Instruction *CxtI, const DominatorTree *DT,
-    bool UseInstrInfo) {
-  KnownBits LHSKnown = computeKnownBits(LHS, DL, /*Depth=*/0, AC, CxtI, DT,
-                                        nullptr, UseInstrInfo);
-  if (LHSKnown.isNonNegative() || LHSKnown.isNegative()) {
-    KnownBits RHSKnown = computeKnownBits(RHS, DL, /*Depth=*/0, AC, CxtI, DT,
-                                          nullptr, UseInstrInfo);
-
-    if (LHSKnown.isNegative() && RHSKnown.isNegative()) {
-      // The sign bit is set in both cases: this MUST overflow.
-      return OverflowResult::AlwaysOverflows;
-    }
-
-    if (LHSKnown.isNonNegative() && RHSKnown.isNonNegative()) {
-      // The sign bit is clear in both cases: this CANNOT overflow.
-      return OverflowResult::NeverOverflows;
-    }
-  }
-
-  return OverflowResult::MayOverflow;
-}
-
-/// Return true if we can prove that adding the two values of the
-/// knownbits will not overflow.
-/// Otherwise return false.
-static bool checkRippleForSignedAdd(const KnownBits &LHSKnown,
-                                    const KnownBits &RHSKnown) {
-  // Addition of two 2's complement numbers having opposite signs will never
-  // overflow.
-  if ((LHSKnown.isNegative() && RHSKnown.isNonNegative()) ||
-      (LHSKnown.isNonNegative() && RHSKnown.isNegative()))
-    return true;
-
-  // If either of the values is known to be non-negative, adding them can only
-  // overflow if the second is also non-negative, so we can assume that.
-  // Two non-negative numbers will only overflow if there is a carry to the
-  // sign bit, so we can check if even when the values are as big as possible
-  // there is no overflow to the sign bit.
-  if (LHSKnown.isNonNegative() || RHSKnown.isNonNegative()) {
-    APInt MaxLHS = ~LHSKnown.Zero;
-    MaxLHS.clearSignBit();
-    APInt MaxRHS = ~RHSKnown.Zero;
-    MaxRHS.clearSignBit();
-    APInt Result = std::move(MaxLHS) + std::move(MaxRHS);
-    return Result.isSignBitClear();
-  }
-
-  // If either of the values is known to be negative, adding them can only
-  // overflow if the second is also negative, so we can assume that.
-  // Two negative number will only overflow if there is no carry to the sign
-  // bit, so we can check if even when the values are as small as possible
-  // there is overflow to the sign bit.
-  if (LHSKnown.isNegative() || RHSKnown.isNegative()) {
-    APInt MinLHS = LHSKnown.One;
-    MinLHS.clearSignBit();
-    APInt MinRHS = RHSKnown.One;
-    MinRHS.clearSignBit();
-    APInt Result = std::move(MinLHS) + std::move(MinRHS);
-    return Result.isSignBitSet();
-  }
-
-  // If we reached here it means that we know nothing about the sign bits.
-  // In this case we can't know if there will be an overflow, since by
-  // changing the sign bits any two values can be made to overflow.
-  return false;
-}
-
-static OverflowResult computeOverflowForSignedAdd(const Value *LHS,
-                                                  const Value *RHS,
-                                                  const AddOperator *Add,
-                                                  const DataLayout &DL,
-                                                  AssumptionCache *AC,
-                                                  const Instruction *CxtI,
-                                                  const DominatorTree *DT) {
-  if (Add && Add->hasNoSignedWrap()) {
-    return OverflowResult::NeverOverflows;
-  }
-
-  // If LHS and RHS each have at least two sign bits, the addition will look
-  // like
-  //
-  // XX..... +
-  // YY.....
-  //
-  // If the carry into the most significant position is 0, X and Y can't both
-  // be 1 and therefore the carry out of the addition is also 0.
-  //
-  // If the carry into the most significant position is 1, X and Y can't both
-  // be 0 and therefore the carry out of the addition is also 1.
-  //
-  // Since the carry into the most significant position is always equal to
-  // the carry out of the addition, there is no signed overflow.
-  if (ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) > 1 &&
-      ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT) > 1)
-    return OverflowResult::NeverOverflows;
-
-  KnownBits LHSKnown = computeKnownBits(LHS, DL, /*Depth=*/0, AC, CxtI, DT);
-  KnownBits RHSKnown = computeKnownBits(RHS, DL, /*Depth=*/0, AC, CxtI, DT);
-
-  if (checkRippleForSignedAdd(LHSKnown, RHSKnown))
-    return OverflowResult::NeverOverflows;
-
-  // The remaining code needs Add to be available. Early returns if not so.
-  if (!Add)
-    return OverflowResult::MayOverflow;
-
-  // If the sign of Add is the same as at least one of the operands, this add
-  // CANNOT overflow. This is particularly useful when the sum is
-  // @llvm.assume'ed non-negative rather than proved so from analyzing its
-  // operands.
-  bool LHSOrRHSKnownNonNegative =
-      (LHSKnown.isNonNegative() || RHSKnown.isNonNegative());
-  bool LHSOrRHSKnownNegative =
-      (LHSKnown.isNegative() || RHSKnown.isNegative());
-  if (LHSOrRHSKnownNonNegative || LHSOrRHSKnownNegative) {
-    KnownBits AddKnown = computeKnownBits(Add, DL, /*Depth=*/0, AC, CxtI, DT);
-    if ((AddKnown.isNonNegative() && LHSOrRHSKnownNonNegative) ||
-        (AddKnown.isNegative() && LHSOrRHSKnownNegative)) {
-      return OverflowResult::NeverOverflows;
-    }
-  }
-
-  return OverflowResult::MayOverflow;
-}
-
-OverflowResult llvm::computeOverflowForUnsignedSub(const Value *LHS,
-                                                   const Value *RHS,
-                                                   const DataLayout &DL,
-                                                   AssumptionCache *AC,
-                                                   const Instruction *CxtI,
-                                                   const DominatorTree *DT) {
-  KnownBits LHSKnown = computeKnownBits(LHS, DL, /*Depth=*/0, AC, CxtI, DT);
-  if (LHSKnown.isNonNegative() || LHSKnown.isNegative()) {
-    KnownBits RHSKnown = computeKnownBits(RHS, DL, /*Depth=*/0, AC, CxtI, DT);
-
-    // If the LHS is negative and the RHS is non-negative, no unsigned wrap.
-    if (LHSKnown.isNegative() && RHSKnown.isNonNegative())
-      return OverflowResult::NeverOverflows;
-
-    // If the LHS is non-negative and the RHS negative, we always wrap.
-    if (LHSKnown.isNonNegative() && RHSKnown.isNegative())
-      return OverflowResult::AlwaysOverflows;
-  }
-
-  return OverflowResult::MayOverflow;
-}
-
-OverflowResult llvm::computeOverflowForSignedSub(const Value *LHS,
-                                                 const Value *RHS,
-                                                 const DataLayout &DL,
-                                                 AssumptionCache *AC,
-                                                 const Instruction *CxtI,
-                                                 const DominatorTree *DT) {
-  // If LHS and RHS each have at least two sign bits, the subtraction
-  // cannot overflow.
-  if (ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) > 1 &&
-      ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT) > 1)
-    return OverflowResult::NeverOverflows;
-
-  KnownBits LHSKnown = computeKnownBits(LHS, DL, 0, AC, CxtI, DT);
-
-  KnownBits RHSKnown = computeKnownBits(RHS, DL, 0, AC, CxtI, DT);
-
-  // Subtraction of two 2's complement numbers having identical signs will
-  // never overflow.
-  if ((LHSKnown.isNegative() && RHSKnown.isNegative()) ||
-      (LHSKnown.isNonNegative() && RHSKnown.isNonNegative()))
-    return OverflowResult::NeverOverflows;
-
-  // TODO: implement logic similar to checkRippleForAdd
-  return OverflowResult::MayOverflow;
-}
-
-bool llvm::isOverflowIntrinsicNoWrap(const IntrinsicInst *II,
-                                     const DominatorTree &DT) {
-#ifndef NDEBUG
-  auto IID = II->getIntrinsicID();
-  assert((IID == Intrinsic::sadd_with_overflow ||
-          IID == Intrinsic::uadd_with_overflow ||
-          IID == Intrinsic::ssub_with_overflow ||
-          IID == Intrinsic::usub_with_overflow ||
-          IID == Intrinsic::smul_with_overflow ||
-          IID == Intrinsic::umul_with_overflow) &&
-         "Not an overflow intrinsic!");
-#endif
-
-  SmallVector<const BranchInst *, 2> GuardingBranches;
-  SmallVector<const ExtractValueInst *, 2> Results;
-
-  for (const User *U : II->users()) {
-    if (const auto *EVI = dyn_cast<ExtractValueInst>(U)) {
-      assert(EVI->getNumIndices() == 1 && "Obvious from CI's type");
-
-      if (EVI->getIndices()[0] == 0)
-        Results.push_back(EVI);
-      else {
-        assert(EVI->getIndices()[0] == 1 && "Obvious from CI's type");
-
-        for (const auto *U : EVI->users())
-          if (const auto *B = dyn_cast<BranchInst>(U)) {
-            assert(B->isConditional() && "How else is it using an i1?");
-            GuardingBranches.push_back(B);
-          }
-      }
-    } else {
-      // We are using the aggregate directly in a way we don't want to analyze
-      // here (storing it to a global, say).
-      return false;
-    }
-  }
-
-  auto AllUsesGuardedByBranch = [&](const BranchInst *BI) {
-    BasicBlockEdge NoWrapEdge(BI->getParent(), BI->getSuccessor(1));
-    if (!NoWrapEdge.isSingleEdge())
-      return false;
-
-    // Check if all users of the add are provably no-wrap.
-    for (const auto *Result : Results) {
-      // If the extractvalue itself is not executed on overflow, the we don't
-      // need to check each use separately, since domination is transitive.
-      if (DT.dominates(NoWrapEdge, Result->getParent()))
-        continue;
-
-      for (auto &RU : Result->uses())
-        if (!DT.dominates(NoWrapEdge, RU))
-          return false;
-    }
-
-    return true;
-  };
-
-  return llvm::any_of(GuardingBranches, AllUsesGuardedByBranch);
-}
-
-
-OverflowResult llvm::computeOverflowForSignedAdd(const AddOperator *Add,
-                                                 const DataLayout &DL,
-                                                 AssumptionCache *AC,
-                                                 const Instruction *CxtI,
-                                                 const DominatorTree *DT) {
-  return ::computeOverflowForSignedAdd(Add->getOperand(0), Add->getOperand(1),
-                                       Add, DL, AC, CxtI, DT);
-}
-
-OverflowResult llvm::computeOverflowForSignedAdd(const Value *LHS,
-                                                 const Value *RHS,
-                                                 const DataLayout &DL,
-                                                 AssumptionCache *AC,
-                                                 const Instruction *CxtI,
-                                                 const DominatorTree *DT) {
-  return ::computeOverflowForSignedAdd(LHS, RHS, nullptr, DL, AC, CxtI, DT);
-}
-
-bool llvm::isGuaranteedToTransferExecutionToSuccessor(const Instruction *I) {
-  // A memory operation returns normally if it isn't volatile. A volatile
-  // operation is allowed to trap.
-  //
-  // An atomic operation isn't guaranteed to return in a reasonable amount of
-  // time because it's possible for another thread to interfere with it for an
-  // arbitrary length of time, but programs aren't allowed to rely on that.
-  if (const LoadInst *LI = dyn_cast<LoadInst>(I))
-    return !LI->isVolatile();
-  if (const StoreInst *SI = dyn_cast<StoreInst>(I))
-    return !SI->isVolatile();
-  if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I))
-    return !CXI->isVolatile();
-  if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I))
-    return !RMWI->isVolatile();
-  if (const MemIntrinsic *MII = dyn_cast<MemIntrinsic>(I))
-    return !MII->isVolatile();
-
-  // If there is no successor, then execution can't transfer to it.
-  if (const auto *CRI = dyn_cast<CleanupReturnInst>(I))
-    return !CRI->unwindsToCaller();
-  if (const auto *CatchSwitch = dyn_cast<CatchSwitchInst>(I))
-    return !CatchSwitch->unwindsToCaller();
-  if (isa<ResumeInst>(I))
-    return false;
-  if (isa<ReturnInst>(I))
-    return false;
-  if (isa<UnreachableInst>(I))
-    return false;
-
-  // Calls can throw, or contain an infinite loop, or kill the process.
-  if (auto CS = ImmutableCallSite(I)) {
-    // Call sites that throw have implicit non-local control flow.
-    if (!CS.doesNotThrow())
-      return false;
-
-    // Non-throwing call sites can loop infinitely, call exit/pthread_exit
-    // etc. and thus not return.  However, LLVM already assumes that
-    //
-    //  - Thread exiting actions are modeled as writes to memory invisible to
-    //    the program.
-    //
-    //  - Loops that don't have side effects (side effects are volatile/atomic
-    //    stores and IO) always terminate (see http://llvm.org/PR965).
-    //    Furthermore IO itself is also modeled as writes to memory invisible to
-    //    the program.
-    //
-    // We rely on those assumptions here, and use the memory effects of the call
-    // target as a proxy for checking that it always returns.
-
-    // FIXME: This isn't aggressive enough; a call which only writes to a global
-    // is guaranteed to return.
-    return CS.onlyReadsMemory() || CS.onlyAccessesArgMemory() ||
-           match(I, m_Intrinsic<Intrinsic::assume>()) ||
-           match(I, m_Intrinsic<Intrinsic::sideeffect>());
-  }
-
-  // Other instructions return normally.
-  return true;
-}
-
-bool llvm::isGuaranteedToTransferExecutionToSuccessor(const BasicBlock *BB) {
-  // TODO: This is slightly consdervative for invoke instruction since exiting
-  // via an exception *is* normal control for them.
-  for (auto I = BB->begin(), E = BB->end(); I != E; ++I)
-    if (!isGuaranteedToTransferExecutionToSuccessor(&*I))
-      return false;
-  return true;
-}
-
-bool llvm::isGuaranteedToExecuteForEveryIteration(const Instruction *I,
-                                                  const Loop *L) {
-  // The loop header is guaranteed to be executed for every iteration.
-  //
-  // FIXME: Relax this constraint to cover all basic blocks that are
-  // guaranteed to be executed at every iteration.
-  if (I->getParent() != L->getHeader()) return false;
-
-  for (const Instruction &LI : *L->getHeader()) {
-    if (&LI == I) return true;
-    if (!isGuaranteedToTransferExecutionToSuccessor(&LI)) return false;
-  }
-  llvm_unreachable("Instruction not contained in its own parent basic block.");
-}
-
-bool llvm::propagatesFullPoison(const Instruction *I) {
-  switch (I->getOpcode()) {
-  case Instruction::Add:
-  case Instruction::Sub:
-  case Instruction::Xor:
-  case Instruction::Trunc:
-  case Instruction::BitCast:
-  case Instruction::AddrSpaceCast:
-  case Instruction::Mul:
-  case Instruction::Shl:
-  case Instruction::GetElementPtr:
-    // These operations all propagate poison unconditionally. Note that poison
-    // is not any particular value, so xor or subtraction of poison with
-    // itself still yields poison, not zero.
-    return true;
-
-  case Instruction::AShr:
-  case Instruction::SExt:
-    // For these operations, one bit of the input is replicated across
-    // multiple output bits. A replicated poison bit is still poison.
-    return true;
-
-  case Instruction::ICmp:
-    // Comparing poison with any value yields poison.  This is why, for
-    // instance, x s< (x +nsw 1) can be folded to true.
-    return true;
-
-  default:
-    return false;
-  }
-}
-
-const Value *llvm::getGuaranteedNonFullPoisonOp(const Instruction *I) {
-  switch (I->getOpcode()) {
-    case Instruction::Store:
-      return cast<StoreInst>(I)->getPointerOperand();
-
-    case Instruction::Load:
-      return cast<LoadInst>(I)->getPointerOperand();
-
-    case Instruction::AtomicCmpXchg:
-      return cast<AtomicCmpXchgInst>(I)->getPointerOperand();
-
-    case Instruction::AtomicRMW:
-      return cast<AtomicRMWInst>(I)->getPointerOperand();
-
-    case Instruction::UDiv:
-    case Instruction::SDiv:
-    case Instruction::URem:
-    case Instruction::SRem:
-      return I->getOperand(1);
-
-    default:
-      return nullptr;
-  }
-}
-
-bool llvm::programUndefinedIfFullPoison(const Instruction *PoisonI) {
-  // We currently only look for uses of poison values within the same basic
-  // block, as that makes it easier to guarantee that the uses will be
-  // executed given that PoisonI is executed.
-  //
-  // FIXME: Expand this to consider uses beyond the same basic block. To do
-  // this, look out for the distinction between post-dominance and strong
-  // post-dominance.
-  const BasicBlock *BB = PoisonI->getParent();
-
-  // Set of instructions that we have proved will yield poison if PoisonI
-  // does.
-  SmallSet<const Value *, 16> YieldsPoison;
-  SmallSet<const BasicBlock *, 4> Visited;
-  YieldsPoison.insert(PoisonI);
-  Visited.insert(PoisonI->getParent());
-
-  BasicBlock::const_iterator Begin = PoisonI->getIterator(), End = BB->end();
-
-  unsigned Iter = 0;
-  while (Iter++ < MaxDepth) {
-    for (auto &I : make_range(Begin, End)) {
-      if (&I != PoisonI) {
-        const Value *NotPoison = getGuaranteedNonFullPoisonOp(&I);
-        if (NotPoison != nullptr && YieldsPoison.count(NotPoison))
-          return true;
-        if (!isGuaranteedToTransferExecutionToSuccessor(&I))
-          return false;
-      }
-
-      // Mark poison that propagates from I through uses of I.
-      if (YieldsPoison.count(&I)) {
-        for (const User *User : I.users()) {
-          const Instruction *UserI = cast<Instruction>(User);
-          if (propagatesFullPoison(UserI))
-            YieldsPoison.insert(User);
-        }
-      }
-    }
-
-    if (auto *NextBB = BB->getSingleSuccessor()) {
-      if (Visited.insert(NextBB).second) {
-        BB = NextBB;
-        Begin = BB->getFirstNonPHI()->getIterator();
-        End = BB->end();
-        continue;
-      }
-    }
-
-    break;
-  }
-  return false;
-}
-
-static bool isKnownNonNaN(const Value *V, FastMathFlags FMF) {
-  if (FMF.noNaNs())
-    return true;
-
-  if (auto *C = dyn_cast<ConstantFP>(V))
-    return !C->isNaN();
-
-  if (auto *C = dyn_cast<ConstantDataVector>(V)) {
-    if (!C->getElementType()->isFloatingPointTy())
-      return false;
-    for (unsigned I = 0, E = C->getNumElements(); I < E; ++I) {
-      if (C->getElementAsAPFloat(I).isNaN())
-        return false;
-    }
-    return true;
-  }
-
-  return false;
-}
-
-static bool isKnownNonZero(const Value *V) {
-  if (auto *C = dyn_cast<ConstantFP>(V))
-    return !C->isZero();
-
-  if (auto *C = dyn_cast<ConstantDataVector>(V)) {
-    if (!C->getElementType()->isFloatingPointTy())
-      return false;
-    for (unsigned I = 0, E = C->getNumElements(); I < E; ++I) {
-      if (C->getElementAsAPFloat(I).isZero())
-        return false;
-    }
-    return true;
-  }
-
-  return false;
-}
-
-/// Match clamp pattern for float types without care about NaNs or signed zeros.
-/// Given non-min/max outer cmp/select from the clamp pattern this
-/// function recognizes if it can be substitued by a "canonical" min/max
-/// pattern.
-static SelectPatternResult matchFastFloatClamp(CmpInst::Predicate Pred,
-                                               Value *CmpLHS, Value *CmpRHS,
-                                               Value *TrueVal, Value *FalseVal,
-                                               Value *&LHS, Value *&RHS) {
-  // Try to match
-  //   X < C1 ? C1 : Min(X, C2) --> Max(C1, Min(X, C2))
-  //   X > C1 ? C1 : Max(X, C2) --> Min(C1, Max(X, C2))
-  // and return description of the outer Max/Min.
-
-  // First, check if select has inverse order:
-  if (CmpRHS == FalseVal) {
-    std::swap(TrueVal, FalseVal);
-    Pred = CmpInst::getInversePredicate(Pred);
-  }
-
-  // Assume success now. If there's no match, callers should not use these anyway.
-  LHS = TrueVal;
-  RHS = FalseVal;
-
-  const APFloat *FC1;
-  if (CmpRHS != TrueVal || !match(CmpRHS, m_APFloat(FC1)) || !FC1->isFinite())
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  const APFloat *FC2;
-  switch (Pred) {
-  case CmpInst::FCMP_OLT:
-  case CmpInst::FCMP_OLE:
-  case CmpInst::FCMP_ULT:
-  case CmpInst::FCMP_ULE:
-    if (match(FalseVal,
-              m_CombineOr(m_OrdFMin(m_Specific(CmpLHS), m_APFloat(FC2)),
-                          m_UnordFMin(m_Specific(CmpLHS), m_APFloat(FC2)))) &&
-        FC1->compare(*FC2) == APFloat::cmpResult::cmpLessThan)
-      return {SPF_FMAXNUM, SPNB_RETURNS_ANY, false};
-    break;
-  case CmpInst::FCMP_OGT:
-  case CmpInst::FCMP_OGE:
-  case CmpInst::FCMP_UGT:
-  case CmpInst::FCMP_UGE:
-    if (match(FalseVal,
-              m_CombineOr(m_OrdFMax(m_Specific(CmpLHS), m_APFloat(FC2)),
-                          m_UnordFMax(m_Specific(CmpLHS), m_APFloat(FC2)))) &&
-        FC1->compare(*FC2) == APFloat::cmpResult::cmpGreaterThan)
-      return {SPF_FMINNUM, SPNB_RETURNS_ANY, false};
-    break;
-  default:
-    break;
-  }
-
-  return {SPF_UNKNOWN, SPNB_NA, false};
-}
-
-/// Recognize variations of:
-///   CLAMP(v,l,h) ==> ((v) < (l) ? (l) : ((v) > (h) ? (h) : (v)))
-static SelectPatternResult matchClamp(CmpInst::Predicate Pred,
-                                      Value *CmpLHS, Value *CmpRHS,
-                                      Value *TrueVal, Value *FalseVal) {
-  // Swap the select operands and predicate to match the patterns below.
-  if (CmpRHS != TrueVal) {
-    Pred = ICmpInst::getSwappedPredicate(Pred);
-    std::swap(TrueVal, FalseVal);
-  }
-  const APInt *C1;
-  if (CmpRHS == TrueVal && match(CmpRHS, m_APInt(C1))) {
-    const APInt *C2;
-    // (X <s C1) ? C1 : SMIN(X, C2) ==> SMAX(SMIN(X, C2), C1)
-    if (match(FalseVal, m_SMin(m_Specific(CmpLHS), m_APInt(C2))) &&
-        C1->slt(*C2) && Pred == CmpInst::ICMP_SLT)
-      return {SPF_SMAX, SPNB_NA, false};
-
-    // (X >s C1) ? C1 : SMAX(X, C2) ==> SMIN(SMAX(X, C2), C1)
-    if (match(FalseVal, m_SMax(m_Specific(CmpLHS), m_APInt(C2))) &&
-        C1->sgt(*C2) && Pred == CmpInst::ICMP_SGT)
-      return {SPF_SMIN, SPNB_NA, false};
-
-    // (X <u C1) ? C1 : UMIN(X, C2) ==> UMAX(UMIN(X, C2), C1)
-    if (match(FalseVal, m_UMin(m_Specific(CmpLHS), m_APInt(C2))) &&
-        C1->ult(*C2) && Pred == CmpInst::ICMP_ULT)
-      return {SPF_UMAX, SPNB_NA, false};
-
-    // (X >u C1) ? C1 : UMAX(X, C2) ==> UMIN(UMAX(X, C2), C1)
-    if (match(FalseVal, m_UMax(m_Specific(CmpLHS), m_APInt(C2))) &&
-        C1->ugt(*C2) && Pred == CmpInst::ICMP_UGT)
-      return {SPF_UMIN, SPNB_NA, false};
-  }
-  return {SPF_UNKNOWN, SPNB_NA, false};
-}
-
-/// Recognize variations of:
-///   a < c ? min(a,b) : min(b,c) ==> min(min(a,b),min(b,c))
-static SelectPatternResult matchMinMaxOfMinMax(CmpInst::Predicate Pred,
-                                               Value *CmpLHS, Value *CmpRHS,
-                                               Value *TVal, Value *FVal,
-                                               unsigned Depth) {
-  // TODO: Allow FP min/max with nnan/nsz.
-  assert(CmpInst::isIntPredicate(Pred) && "Expected integer comparison");
-
-  Value *A, *B;
-  SelectPatternResult L = matchSelectPattern(TVal, A, B, nullptr, Depth + 1);
-  if (!SelectPatternResult::isMinOrMax(L.Flavor))
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  Value *C, *D;
-  SelectPatternResult R = matchSelectPattern(FVal, C, D, nullptr, Depth + 1);
-  if (L.Flavor != R.Flavor)
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  // We have something like: x Pred y ? min(a, b) : min(c, d).
-  // Try to match the compare to the min/max operations of the select operands.
-  // First, make sure we have the right compare predicate.
-  switch (L.Flavor) {
-  case SPF_SMIN:
-    if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE) {
-      Pred = ICmpInst::getSwappedPredicate(Pred);
-      std::swap(CmpLHS, CmpRHS);
-    }
-    if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE)
-      break;
-    return {SPF_UNKNOWN, SPNB_NA, false};
-  case SPF_SMAX:
-    if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE) {
-      Pred = ICmpInst::getSwappedPredicate(Pred);
-      std::swap(CmpLHS, CmpRHS);
-    }
-    if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE)
-      break;
-    return {SPF_UNKNOWN, SPNB_NA, false};
-  case SPF_UMIN:
-    if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_UGE) {
-      Pred = ICmpInst::getSwappedPredicate(Pred);
-      std::swap(CmpLHS, CmpRHS);
-    }
-    if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_ULE)
-      break;
-    return {SPF_UNKNOWN, SPNB_NA, false};
-  case SPF_UMAX:
-    if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_ULE) {
-      Pred = ICmpInst::getSwappedPredicate(Pred);
-      std::swap(CmpLHS, CmpRHS);
-    }
-    if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_UGE)
-      break;
-    return {SPF_UNKNOWN, SPNB_NA, false};
-  default:
-    return {SPF_UNKNOWN, SPNB_NA, false};
-  }
-
-  // If there is a common operand in the already matched min/max and the other
-  // min/max operands match the compare operands (either directly or inverted),
-  // then this is min/max of the same flavor.
-
-  // a pred c ? m(a, b) : m(c, b) --> m(m(a, b), m(c, b))
-  // ~c pred ~a ? m(a, b) : m(c, b) --> m(m(a, b), m(c, b))
-  if (D == B) {
-    if ((CmpLHS == A && CmpRHS == C) || (match(C, m_Not(m_Specific(CmpLHS))) &&
-                                         match(A, m_Not(m_Specific(CmpRHS)))))
-      return {L.Flavor, SPNB_NA, false};
-  }
-  // a pred d ? m(a, b) : m(b, d) --> m(m(a, b), m(b, d))
-  // ~d pred ~a ? m(a, b) : m(b, d) --> m(m(a, b), m(b, d))
-  if (C == B) {
-    if ((CmpLHS == A && CmpRHS == D) || (match(D, m_Not(m_Specific(CmpLHS))) &&
-                                         match(A, m_Not(m_Specific(CmpRHS)))))
-      return {L.Flavor, SPNB_NA, false};
-  }
-  // b pred c ? m(a, b) : m(c, a) --> m(m(a, b), m(c, a))
-  // ~c pred ~b ? m(a, b) : m(c, a) --> m(m(a, b), m(c, a))
-  if (D == A) {
-    if ((CmpLHS == B && CmpRHS == C) || (match(C, m_Not(m_Specific(CmpLHS))) &&
-                                         match(B, m_Not(m_Specific(CmpRHS)))))
-      return {L.Flavor, SPNB_NA, false};
-  }
-  // b pred d ? m(a, b) : m(a, d) --> m(m(a, b), m(a, d))
-  // ~d pred ~b ? m(a, b) : m(a, d) --> m(m(a, b), m(a, d))
-  if (C == A) {
-    if ((CmpLHS == B && CmpRHS == D) || (match(D, m_Not(m_Specific(CmpLHS))) &&
-                                         match(B, m_Not(m_Specific(CmpRHS)))))
-      return {L.Flavor, SPNB_NA, false};
-  }
-
-  return {SPF_UNKNOWN, SPNB_NA, false};
-}
-
-/// Match non-obvious integer minimum and maximum sequences.
-static SelectPatternResult matchMinMax(CmpInst::Predicate Pred,
-                                       Value *CmpLHS, Value *CmpRHS,
-                                       Value *TrueVal, Value *FalseVal,
-                                       Value *&LHS, Value *&RHS,
-                                       unsigned Depth) {
-  // Assume success. If there's no match, callers should not use these anyway.
-  LHS = TrueVal;
-  RHS = FalseVal;
-
-  SelectPatternResult SPR = matchClamp(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal);
-  if (SPR.Flavor != SelectPatternFlavor::SPF_UNKNOWN)
-    return SPR;
-
-  SPR = matchMinMaxOfMinMax(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, Depth);
-  if (SPR.Flavor != SelectPatternFlavor::SPF_UNKNOWN)
-    return SPR;
-
-  if (Pred != CmpInst::ICMP_SGT && Pred != CmpInst::ICMP_SLT)
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  // Z = X -nsw Y
-  // (X >s Y) ? 0 : Z ==> (Z >s 0) ? 0 : Z ==> SMIN(Z, 0)
-  // (X <s Y) ? 0 : Z ==> (Z <s 0) ? 0 : Z ==> SMAX(Z, 0)
-  if (match(TrueVal, m_Zero()) &&
-      match(FalseVal, m_NSWSub(m_Specific(CmpLHS), m_Specific(CmpRHS))))
-    return {Pred == CmpInst::ICMP_SGT ? SPF_SMIN : SPF_SMAX, SPNB_NA, false};
-
-  // Z = X -nsw Y
-  // (X >s Y) ? Z : 0 ==> (Z >s 0) ? Z : 0 ==> SMAX(Z, 0)
-  // (X <s Y) ? Z : 0 ==> (Z <s 0) ? Z : 0 ==> SMIN(Z, 0)
-  if (match(FalseVal, m_Zero()) &&
-      match(TrueVal, m_NSWSub(m_Specific(CmpLHS), m_Specific(CmpRHS))))
-    return {Pred == CmpInst::ICMP_SGT ? SPF_SMAX : SPF_SMIN, SPNB_NA, false};
-
-  const APInt *C1;
-  if (!match(CmpRHS, m_APInt(C1)))
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  // An unsigned min/max can be written with a signed compare.
-  const APInt *C2;
-  if ((CmpLHS == TrueVal && match(FalseVal, m_APInt(C2))) ||
-      (CmpLHS == FalseVal && match(TrueVal, m_APInt(C2)))) {
-    // Is the sign bit set?
-    // (X <s 0) ? X : MAXVAL ==> (X >u MAXVAL) ? X : MAXVAL ==> UMAX
-    // (X <s 0) ? MAXVAL : X ==> (X >u MAXVAL) ? MAXVAL : X ==> UMIN
-    if (Pred == CmpInst::ICMP_SLT && C1->isNullValue() &&
-        C2->isMaxSignedValue())
-      return {CmpLHS == TrueVal ? SPF_UMAX : SPF_UMIN, SPNB_NA, false};
-
-    // Is the sign bit clear?
-    // (X >s -1) ? MINVAL : X ==> (X <u MINVAL) ? MINVAL : X ==> UMAX
-    // (X >s -1) ? X : MINVAL ==> (X <u MINVAL) ? X : MINVAL ==> UMIN
-    if (Pred == CmpInst::ICMP_SGT && C1->isAllOnesValue() &&
-        C2->isMinSignedValue())
-      return {CmpLHS == FalseVal ? SPF_UMAX : SPF_UMIN, SPNB_NA, false};
-  }
-
-  // Look through 'not' ops to find disguised signed min/max.
-  // (X >s C) ? ~X : ~C ==> (~X <s ~C) ? ~X : ~C ==> SMIN(~X, ~C)
-  // (X <s C) ? ~X : ~C ==> (~X >s ~C) ? ~X : ~C ==> SMAX(~X, ~C)
-  if (match(TrueVal, m_Not(m_Specific(CmpLHS))) &&
-      match(FalseVal, m_APInt(C2)) && ~(*C1) == *C2)
-    return {Pred == CmpInst::ICMP_SGT ? SPF_SMIN : SPF_SMAX, SPNB_NA, false};
-
-  // (X >s C) ? ~C : ~X ==> (~X <s ~C) ? ~C : ~X ==> SMAX(~C, ~X)
-  // (X <s C) ? ~C : ~X ==> (~X >s ~C) ? ~C : ~X ==> SMIN(~C, ~X)
-  if (match(FalseVal, m_Not(m_Specific(CmpLHS))) &&
-      match(TrueVal, m_APInt(C2)) && ~(*C1) == *C2)
-    return {Pred == CmpInst::ICMP_SGT ? SPF_SMAX : SPF_SMIN, SPNB_NA, false};
-
-  return {SPF_UNKNOWN, SPNB_NA, false};
-}
-
-bool llvm::isKnownNegation(const Value *X, const Value *Y, bool NeedNSW) {
-  assert(X && Y && "Invalid operand");
-
-  // X = sub (0, Y) || X = sub nsw (0, Y)
-  if ((!NeedNSW && match(X, m_Sub(m_ZeroInt(), m_Specific(Y)))) ||
-      (NeedNSW && match(X, m_NSWSub(m_ZeroInt(), m_Specific(Y)))))
-    return true;
-
-  // Y = sub (0, X) || Y = sub nsw (0, X)
-  if ((!NeedNSW && match(Y, m_Sub(m_ZeroInt(), m_Specific(X)))) ||
-      (NeedNSW && match(Y, m_NSWSub(m_ZeroInt(), m_Specific(X)))))
-    return true;
-
-  // X = sub (A, B), Y = sub (B, A) || X = sub nsw (A, B), Y = sub nsw (B, A)
-  Value *A, *B;
-  return (!NeedNSW && (match(X, m_Sub(m_Value(A), m_Value(B))) &&
-                        match(Y, m_Sub(m_Specific(B), m_Specific(A))))) ||
-         (NeedNSW && (match(X, m_NSWSub(m_Value(A), m_Value(B))) &&
-                       match(Y, m_NSWSub(m_Specific(B), m_Specific(A)))));
-}
-
-static SelectPatternResult matchSelectPattern(CmpInst::Predicate Pred,
-                                              FastMathFlags FMF,
-                                              Value *CmpLHS, Value *CmpRHS,
-                                              Value *TrueVal, Value *FalseVal,
-                                              Value *&LHS, Value *&RHS,
-                                              unsigned Depth) {
-  if (CmpInst::isFPPredicate(Pred)) {
-    // IEEE-754 ignores the sign of 0.0 in comparisons. So if the select has one
-    // 0.0 operand, set the compare's 0.0 operands to that same value for the
-    // purpose of identifying min/max. Disregard vector constants with undefined
-    // elements because those can not be back-propagated for analysis.
-    Value *OutputZeroVal = nullptr;
-    if (match(TrueVal, m_AnyZeroFP()) && !match(FalseVal, m_AnyZeroFP()) &&
-        !cast<Constant>(TrueVal)->containsUndefElement())
-      OutputZeroVal = TrueVal;
-    else if (match(FalseVal, m_AnyZeroFP()) && !match(TrueVal, m_AnyZeroFP()) &&
-             !cast<Constant>(FalseVal)->containsUndefElement())
-      OutputZeroVal = FalseVal;
-
-    if (OutputZeroVal) {
-      if (match(CmpLHS, m_AnyZeroFP()))
-        CmpLHS = OutputZeroVal;
-      if (match(CmpRHS, m_AnyZeroFP()))
-        CmpRHS = OutputZeroVal;
-    }
-  }
-
-  LHS = CmpLHS;
-  RHS = CmpRHS;
-
-  // Signed zero may return inconsistent results between implementations.
-  //  (0.0 <= -0.0) ? 0.0 : -0.0 // Returns 0.0
-  //  minNum(0.0, -0.0)          // May return -0.0 or 0.0 (IEEE 754-2008 5.3.1)
-  // Therefore, we behave conservatively and only proceed if at least one of the
-  // operands is known to not be zero or if we don't care about signed zero.
-  switch (Pred) {
-  default: break;
-  // FIXME: Include OGT/OLT/UGT/ULT.
-  case CmpInst::FCMP_OGE: case CmpInst::FCMP_OLE:
-  case CmpInst::FCMP_UGE: case CmpInst::FCMP_ULE:
-    if (!FMF.noSignedZeros() && !isKnownNonZero(CmpLHS) &&
-        !isKnownNonZero(CmpRHS))
-      return {SPF_UNKNOWN, SPNB_NA, false};
-  }
-
-  SelectPatternNaNBehavior NaNBehavior = SPNB_NA;
-  bool Ordered = false;
-
-  // When given one NaN and one non-NaN input:
-  //   - maxnum/minnum (C99 fmaxf()/fminf()) return the non-NaN input.
-  //   - A simple C99 (a < b ? a : b) construction will return 'b' (as the
-  //     ordered comparison fails), which could be NaN or non-NaN.
-  // so here we discover exactly what NaN behavior is required/accepted.
-  if (CmpInst::isFPPredicate(Pred)) {
-    bool LHSSafe = isKnownNonNaN(CmpLHS, FMF);
-    bool RHSSafe = isKnownNonNaN(CmpRHS, FMF);
-
-    if (LHSSafe && RHSSafe) {
-      // Both operands are known non-NaN.
-      NaNBehavior = SPNB_RETURNS_ANY;
-    } else if (CmpInst::isOrdered(Pred)) {
-      // An ordered comparison will return false when given a NaN, so it
-      // returns the RHS.
-      Ordered = true;
-      if (LHSSafe)
-        // LHS is non-NaN, so if RHS is NaN then NaN will be returned.
-        NaNBehavior = SPNB_RETURNS_NAN;
-      else if (RHSSafe)
-        NaNBehavior = SPNB_RETURNS_OTHER;
-      else
-        // Completely unsafe.
-        return {SPF_UNKNOWN, SPNB_NA, false};
-    } else {
-      Ordered = false;
-      // An unordered comparison will return true when given a NaN, so it
-      // returns the LHS.
-      if (LHSSafe)
-        // LHS is non-NaN, so if RHS is NaN then non-NaN will be returned.
-        NaNBehavior = SPNB_RETURNS_OTHER;
-      else if (RHSSafe)
-        NaNBehavior = SPNB_RETURNS_NAN;
-      else
-        // Completely unsafe.
-        return {SPF_UNKNOWN, SPNB_NA, false};
-    }
-  }
-
-  if (TrueVal == CmpRHS && FalseVal == CmpLHS) {
-    std::swap(CmpLHS, CmpRHS);
-    Pred = CmpInst::getSwappedPredicate(Pred);
-    if (NaNBehavior == SPNB_RETURNS_NAN)
-      NaNBehavior = SPNB_RETURNS_OTHER;
-    else if (NaNBehavior == SPNB_RETURNS_OTHER)
-      NaNBehavior = SPNB_RETURNS_NAN;
-    Ordered = !Ordered;
-  }
-
-  // ([if]cmp X, Y) ? X : Y
-  if (TrueVal == CmpLHS && FalseVal == CmpRHS) {
-    switch (Pred) {
-    default: return {SPF_UNKNOWN, SPNB_NA, false}; // Equality.
-    case ICmpInst::ICMP_UGT:
-    case ICmpInst::ICMP_UGE: return {SPF_UMAX, SPNB_NA, false};
-    case ICmpInst::ICMP_SGT:
-    case ICmpInst::ICMP_SGE: return {SPF_SMAX, SPNB_NA, false};
-    case ICmpInst::ICMP_ULT:
-    case ICmpInst::ICMP_ULE: return {SPF_UMIN, SPNB_NA, false};
-    case ICmpInst::ICMP_SLT:
-    case ICmpInst::ICMP_SLE: return {SPF_SMIN, SPNB_NA, false};
-    case FCmpInst::FCMP_UGT:
-    case FCmpInst::FCMP_UGE:
-    case FCmpInst::FCMP_OGT:
-    case FCmpInst::FCMP_OGE: return {SPF_FMAXNUM, NaNBehavior, Ordered};
-    case FCmpInst::FCMP_ULT:
-    case FCmpInst::FCMP_ULE:
-    case FCmpInst::FCMP_OLT:
-    case FCmpInst::FCMP_OLE: return {SPF_FMINNUM, NaNBehavior, Ordered};
-    }
-  }
-
-  if (isKnownNegation(TrueVal, FalseVal)) {
-    // Sign-extending LHS does not change its sign, so TrueVal/FalseVal can
-    // match against either LHS or sext(LHS).
-    auto MaybeSExtCmpLHS =
-        m_CombineOr(m_Specific(CmpLHS), m_SExt(m_Specific(CmpLHS)));
-    auto ZeroOrAllOnes = m_CombineOr(m_ZeroInt(), m_AllOnes());
-    auto ZeroOrOne = m_CombineOr(m_ZeroInt(), m_One());
-    if (match(TrueVal, MaybeSExtCmpLHS)) {
-      // Set the return values. If the compare uses the negated value (-X >s 0),
-      // swap the return values because the negated value is always 'RHS'.
-      LHS = TrueVal;
-      RHS = FalseVal;
-      if (match(CmpLHS, m_Neg(m_Specific(FalseVal))))
-        std::swap(LHS, RHS);
-
-      // (X >s 0) ? X : -X or (X >s -1) ? X : -X --> ABS(X)
-      // (-X >s 0) ? -X : X or (-X >s -1) ? -X : X --> ABS(X)
-      if (Pred == ICmpInst::ICMP_SGT && match(CmpRHS, ZeroOrAllOnes))
-        return {SPF_ABS, SPNB_NA, false};
-
-      // (X <s 0) ? X : -X or (X <s 1) ? X : -X --> NABS(X)
-      // (-X <s 0) ? -X : X or (-X <s 1) ? -X : X --> NABS(X)
-      if (Pred == ICmpInst::ICMP_SLT && match(CmpRHS, ZeroOrOne))
-        return {SPF_NABS, SPNB_NA, false};
-    }
-    else if (match(FalseVal, MaybeSExtCmpLHS)) {
-      // Set the return values. If the compare uses the negated value (-X >s 0),
-      // swap the return values because the negated value is always 'RHS'.
-      LHS = FalseVal;
-      RHS = TrueVal;
-      if (match(CmpLHS, m_Neg(m_Specific(TrueVal))))
-        std::swap(LHS, RHS);
-
-      // (X >s 0) ? -X : X or (X >s -1) ? -X : X --> NABS(X)
-      // (-X >s 0) ? X : -X or (-X >s -1) ? X : -X --> NABS(X)
-      if (Pred == ICmpInst::ICMP_SGT && match(CmpRHS, ZeroOrAllOnes))
-        return {SPF_NABS, SPNB_NA, false};
-
-      // (X <s 0) ? -X : X or (X <s 1) ? -X : X --> ABS(X)
-      // (-X <s 0) ? X : -X or (-X <s 1) ? X : -X --> ABS(X)
-      if (Pred == ICmpInst::ICMP_SLT && match(CmpRHS, ZeroOrOne))
-        return {SPF_ABS, SPNB_NA, false};
-    }
-  }
-
-  if (CmpInst::isIntPredicate(Pred))
-    return matchMinMax(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, LHS, RHS, Depth);
-
-  // According to (IEEE 754-2008 5.3.1), minNum(0.0, -0.0) and similar
-  // may return either -0.0 or 0.0, so fcmp/select pair has stricter
-  // semantics than minNum. Be conservative in such case.
-  if (NaNBehavior != SPNB_RETURNS_ANY ||
-      (!FMF.noSignedZeros() && !isKnownNonZero(CmpLHS) &&
-       !isKnownNonZero(CmpRHS)))
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  return matchFastFloatClamp(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, LHS, RHS);
-}
-
-/// Helps to match a select pattern in case of a type mismatch.
-///
-/// The function processes the case when type of true and false values of a
-/// select instruction differs from type of the cmp instruction operands because
-/// of a cast instruction. The function checks if it is legal to move the cast
-/// operation after "select". If yes, it returns the new second value of
-/// "select" (with the assumption that cast is moved):
-/// 1. As operand of cast instruction when both values of "select" are same cast
-/// instructions.
-/// 2. As restored constant (by applying reverse cast operation) when the first
-/// value of the "select" is a cast operation and the second value is a
-/// constant.
-/// NOTE: We return only the new second value because the first value could be
-/// accessed as operand of cast instruction.
-static Value *lookThroughCast(CmpInst *CmpI, Value *V1, Value *V2,
-                              Instruction::CastOps *CastOp) {
-  auto *Cast1 = dyn_cast<CastInst>(V1);
-  if (!Cast1)
-    return nullptr;
-
-  *CastOp = Cast1->getOpcode();
-  Type *SrcTy = Cast1->getSrcTy();
-  if (auto *Cast2 = dyn_cast<CastInst>(V2)) {
-    // If V1 and V2 are both the same cast from the same type, look through V1.
-    if (*CastOp == Cast2->getOpcode() && SrcTy == Cast2->getSrcTy())
-      return Cast2->getOperand(0);
-    return nullptr;
-  }
-
-  auto *C = dyn_cast<Constant>(V2);
-  if (!C)
-    return nullptr;
-
-  Constant *CastedTo = nullptr;
-  switch (*CastOp) {
-  case Instruction::ZExt:
-    if (CmpI->isUnsigned())
-      CastedTo = ConstantExpr::getTrunc(C, SrcTy);
-    break;
-  case Instruction::SExt:
-    if (CmpI->isSigned())
-      CastedTo = ConstantExpr::getTrunc(C, SrcTy, true);
-    break;
-  case Instruction::Trunc:
-    Constant *CmpConst;
-    if (match(CmpI->getOperand(1), m_Constant(CmpConst)) &&
-        CmpConst->getType() == SrcTy) {
-      // Here we have the following case:
-      //
-      //   %cond = cmp iN %x, CmpConst
-      //   %tr = trunc iN %x to iK
-      //   %narrowsel = select i1 %cond, iK %t, iK C
-      //
-      // We can always move trunc after select operation:
-      //
-      //   %cond = cmp iN %x, CmpConst
-      //   %widesel = select i1 %cond, iN %x, iN CmpConst
-      //   %tr = trunc iN %widesel to iK
-      //
-      // Note that C could be extended in any way because we don't care about
-      // upper bits after truncation. It can't be abs pattern, because it would
-      // look like:
-      //
-      //   select i1 %cond, x, -x.
-      //
-      // So only min/max pattern could be matched. Such match requires widened C
-      // == CmpConst. That is why set widened C = CmpConst, condition trunc
-      // CmpConst == C is checked below.
-      CastedTo = CmpConst;
-    } else {
-      CastedTo = ConstantExpr::getIntegerCast(C, SrcTy, CmpI->isSigned());
-    }
-    break;
-  case Instruction::FPTrunc:
-    CastedTo = ConstantExpr::getFPExtend(C, SrcTy, true);
-    break;
-  case Instruction::FPExt:
-    CastedTo = ConstantExpr::getFPTrunc(C, SrcTy, true);
-    break;
-  case Instruction::FPToUI:
-    CastedTo = ConstantExpr::getUIToFP(C, SrcTy, true);
-    break;
-  case Instruction::FPToSI:
-    CastedTo = ConstantExpr::getSIToFP(C, SrcTy, true);
-    break;
-  case Instruction::UIToFP:
-    CastedTo = ConstantExpr::getFPToUI(C, SrcTy, true);
-    break;
-  case Instruction::SIToFP:
-    CastedTo = ConstantExpr::getFPToSI(C, SrcTy, true);
-    break;
-  default:
-    break;
-  }
-
-  if (!CastedTo)
-    return nullptr;
-
-  // Make sure the cast doesn't lose any information.
-  Constant *CastedBack =
-      ConstantExpr::getCast(*CastOp, CastedTo, C->getType(), true);
-  if (CastedBack != C)
-    return nullptr;
-
-  return CastedTo;
-}
-
-SelectPatternResult llvm::matchSelectPattern(Value *V, Value *&LHS, Value *&RHS,
-                                             Instruction::CastOps *CastOp,
-                                             unsigned Depth) {
-  if (Depth >= MaxDepth)
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  SelectInst *SI = dyn_cast<SelectInst>(V);
-  if (!SI) return {SPF_UNKNOWN, SPNB_NA, false};
-
-  CmpInst *CmpI = dyn_cast<CmpInst>(SI->getCondition());
-  if (!CmpI) return {SPF_UNKNOWN, SPNB_NA, false};
-
-  CmpInst::Predicate Pred = CmpI->getPredicate();
-  Value *CmpLHS = CmpI->getOperand(0);
-  Value *CmpRHS = CmpI->getOperand(1);
-  Value *TrueVal = SI->getTrueValue();
-  Value *FalseVal = SI->getFalseValue();
-  FastMathFlags FMF;
-  if (isa<FPMathOperator>(CmpI))
-    FMF = CmpI->getFastMathFlags();
-
-  // Bail out early.
-  if (CmpI->isEquality())
-    return {SPF_UNKNOWN, SPNB_NA, false};
-
-  // Deal with type mismatches.
-  if (CastOp && CmpLHS->getType() != TrueVal->getType()) {
-    if (Value *C = lookThroughCast(CmpI, TrueVal, FalseVal, CastOp)) {
-      // If this is a potential fmin/fmax with a cast to integer, then ignore
-      // -0.0 because there is no corresponding integer value.
-      if (*CastOp == Instruction::FPToSI || *CastOp == Instruction::FPToUI)
-        FMF.setNoSignedZeros();
-      return ::matchSelectPattern(Pred, FMF, CmpLHS, CmpRHS,
-                                  cast<CastInst>(TrueVal)->getOperand(0), C,
-                                  LHS, RHS, Depth);
-    }
-    if (Value *C = lookThroughCast(CmpI, FalseVal, TrueVal, CastOp)) {
-      // If this is a potential fmin/fmax with a cast to integer, then ignore
-      // -0.0 because there is no corresponding integer value.
-      if (*CastOp == Instruction::FPToSI || *CastOp == Instruction::FPToUI)
-        FMF.setNoSignedZeros();
-      return ::matchSelectPattern(Pred, FMF, CmpLHS, CmpRHS,
-                                  C, cast<CastInst>(FalseVal)->getOperand(0),
-                                  LHS, RHS, Depth);
-    }
-  }
-  return ::matchSelectPattern(Pred, FMF, CmpLHS, CmpRHS, TrueVal, FalseVal,
-                              LHS, RHS, Depth);
-}
-
-CmpInst::Predicate llvm::getMinMaxPred(SelectPatternFlavor SPF, bool Ordered) {
-  if (SPF == SPF_SMIN) return ICmpInst::ICMP_SLT;
-  if (SPF == SPF_UMIN) return ICmpInst::ICMP_ULT;
-  if (SPF == SPF_SMAX) return ICmpInst::ICMP_SGT;
-  if (SPF == SPF_UMAX) return ICmpInst::ICMP_UGT;
-  if (SPF == SPF_FMINNUM)
-    return Ordered ? FCmpInst::FCMP_OLT : FCmpInst::FCMP_ULT;
-  if (SPF == SPF_FMAXNUM)
-    return Ordered ? FCmpInst::FCMP_OGT : FCmpInst::FCMP_UGT;
-  llvm_unreachable("unhandled!");
-}
-
-SelectPatternFlavor llvm::getInverseMinMaxFlavor(SelectPatternFlavor SPF) {
-  if (SPF == SPF_SMIN) return SPF_SMAX;
-  if (SPF == SPF_UMIN) return SPF_UMAX;
-  if (SPF == SPF_SMAX) return SPF_SMIN;
-  if (SPF == SPF_UMAX) return SPF_UMIN;
-  llvm_unreachable("unhandled!");
-}
-
-CmpInst::Predicate llvm::getInverseMinMaxPred(SelectPatternFlavor SPF) {
-  return getMinMaxPred(getInverseMinMaxFlavor(SPF));
-}
-
-/// Return true if "icmp Pred LHS RHS" is always true.
-static bool isTruePredicate(CmpInst::Predicate Pred, const Value *LHS,
-                            const Value *RHS, const DataLayout &DL,
-                            unsigned Depth) {
-  assert(!LHS->getType()->isVectorTy() && "TODO: extend to handle vectors!");
-  if (ICmpInst::isTrueWhenEqual(Pred) && LHS == RHS)
-    return true;
-
-  switch (Pred) {
-  default:
-    return false;
-
-  case CmpInst::ICMP_SLE: {
-    const APInt *C;
-
-    // LHS s<= LHS +_{nsw} C   if C >= 0
-    if (match(RHS, m_NSWAdd(m_Specific(LHS), m_APInt(C))))
-      return !C->isNegative();
-    return false;
-  }
-
-  case CmpInst::ICMP_ULE: {
-    const APInt *C;
-
-    // LHS u<= LHS +_{nuw} C   for any C
-    if (match(RHS, m_NUWAdd(m_Specific(LHS), m_APInt(C))))
-      return true;
-
-    // Match A to (X +_{nuw} CA) and B to (X +_{nuw} CB)
-    auto MatchNUWAddsToSameValue = [&](const Value *A, const Value *B,
-                                       const Value *&X,
-                                       const APInt *&CA, const APInt *&CB) {
-      if (match(A, m_NUWAdd(m_Value(X), m_APInt(CA))) &&
-          match(B, m_NUWAdd(m_Specific(X), m_APInt(CB))))
-        return true;
-
-      // If X & C == 0 then (X | C) == X +_{nuw} C
-      if (match(A, m_Or(m_Value(X), m_APInt(CA))) &&
-          match(B, m_Or(m_Specific(X), m_APInt(CB)))) {
-        KnownBits Known(CA->getBitWidth());
-        computeKnownBits(X, Known, DL, Depth + 1, /*AC*/ nullptr,
-                         /*CxtI*/ nullptr, /*DT*/ nullptr);
-        if (CA->isSubsetOf(Known.Zero) && CB->isSubsetOf(Known.Zero))
-          return true;
-      }
-
-      return false;
-    };
-
-    const Value *X;
-    const APInt *CLHS, *CRHS;
-    if (MatchNUWAddsToSameValue(LHS, RHS, X, CLHS, CRHS))
-      return CLHS->ule(*CRHS);
-
-    return false;
-  }
-  }
-}
-
-/// Return true if "icmp Pred BLHS BRHS" is true whenever "icmp Pred
-/// ALHS ARHS" is true.  Otherwise, return None.
-static Optional<bool>
-isImpliedCondOperands(CmpInst::Predicate Pred, const Value *ALHS,
-                      const Value *ARHS, const Value *BLHS, const Value *BRHS,
-                      const DataLayout &DL, unsigned Depth) {
-  switch (Pred) {
-  default:
-    return None;
-
-  case CmpInst::ICMP_SLT:
-  case CmpInst::ICMP_SLE:
-    if (isTruePredicate(CmpInst::ICMP_SLE, BLHS, ALHS, DL, Depth) &&
-        isTruePredicate(CmpInst::ICMP_SLE, ARHS, BRHS, DL, Depth))
-      return true;
-    return None;
-
-  case CmpInst::ICMP_ULT:
-  case CmpInst::ICMP_ULE:
-    if (isTruePredicate(CmpInst::ICMP_ULE, BLHS, ALHS, DL, Depth) &&
-        isTruePredicate(CmpInst::ICMP_ULE, ARHS, BRHS, DL, Depth))
-      return true;
-    return None;
-  }
-}
-
-/// Return true if the operands of the two compares match.  IsSwappedOps is true
-/// when the operands match, but are swapped.
-static bool isMatchingOps(const Value *ALHS, const Value *ARHS,
-                          const Value *BLHS, const Value *BRHS,
-                          bool &IsSwappedOps) {
-
-  bool IsMatchingOps = (ALHS == BLHS && ARHS == BRHS);
-  IsSwappedOps = (ALHS == BRHS && ARHS == BLHS);
-  return IsMatchingOps || IsSwappedOps;
-}
-
-/// Return true if "icmp1 APred X, Y" implies "icmp2 BPred X, Y" is true.
-/// Return false if "icmp1 APred X, Y" implies "icmp2 BPred X, Y" is false.
-/// Otherwise, return None if we can't infer anything.
-static Optional<bool> isImpliedCondMatchingOperands(CmpInst::Predicate APred,
-                                                    CmpInst::Predicate BPred,
-                                                    bool AreSwappedOps) {
-  // Canonicalize the predicate as if the operands were not commuted.
-  if (AreSwappedOps)
-    BPred = ICmpInst::getSwappedPredicate(BPred);
-
-  if (CmpInst::isImpliedTrueByMatchingCmp(APred, BPred))
-    return true;
-  if (CmpInst::isImpliedFalseByMatchingCmp(APred, BPred))
-    return false;
-
-  return None;
-}
-
-/// Return true if "icmp APred X, C1" implies "icmp BPred X, C2" is true.
-/// Return false if "icmp APred X, C1" implies "icmp BPred X, C2" is false.
-/// Otherwise, return None if we can't infer anything.
-static Optional<bool>
-isImpliedCondMatchingImmOperands(CmpInst::Predicate APred,
-                                 const ConstantInt *C1,
-                                 CmpInst::Predicate BPred,
-                                 const ConstantInt *C2) {
-  ConstantRange DomCR =
-      ConstantRange::makeExactICmpRegion(APred, C1->getValue());
-  ConstantRange CR =
-      ConstantRange::makeAllowedICmpRegion(BPred, C2->getValue());
-  ConstantRange Intersection = DomCR.intersectWith(CR);
-  ConstantRange Difference = DomCR.difference(CR);
-  if (Intersection.isEmptySet())
-    return false;
-  if (Difference.isEmptySet())
-    return true;
-  return None;
-}
-
-/// Return true if LHS implies RHS is true.  Return false if LHS implies RHS is
-/// false.  Otherwise, return None if we can't infer anything.
-static Optional<bool> isImpliedCondICmps(const ICmpInst *LHS,
-                                         const ICmpInst *RHS,
-                                         const DataLayout &DL, bool LHSIsTrue,
-                                         unsigned Depth) {
-  Value *ALHS = LHS->getOperand(0);
-  Value *ARHS = LHS->getOperand(1);
-  // The rest of the logic assumes the LHS condition is true.  If that's not the
-  // case, invert the predicate to make it so.
-  ICmpInst::Predicate APred =
-      LHSIsTrue ? LHS->getPredicate() : LHS->getInversePredicate();
-
-  Value *BLHS = RHS->getOperand(0);
-  Value *BRHS = RHS->getOperand(1);
-  ICmpInst::Predicate BPred = RHS->getPredicate();
-
-  // Can we infer anything when the two compares have matching operands?
-  bool AreSwappedOps;
-  if (isMatchingOps(ALHS, ARHS, BLHS, BRHS, AreSwappedOps)) {
-    if (Optional<bool> Implication = isImpliedCondMatchingOperands(
-            APred, BPred, AreSwappedOps))
-      return Implication;
-    // No amount of additional analysis will infer the second condition, so
-    // early exit.
-    return None;
-  }
-
-  // Can we infer anything when the LHS operands match and the RHS operands are
-  // constants (not necessarily matching)?
-  if (ALHS == BLHS && isa<ConstantInt>(ARHS) && isa<ConstantInt>(BRHS)) {
-    if (Optional<bool> Implication = isImpliedCondMatchingImmOperands(
-            APred, cast<ConstantInt>(ARHS), BPred, cast<ConstantInt>(BRHS)))
-      return Implication;
-    // No amount of additional analysis will infer the second condition, so
-    // early exit.
-    return None;
-  }
-
-  if (APred == BPred)
-    return isImpliedCondOperands(APred, ALHS, ARHS, BLHS, BRHS, DL, Depth);
-  return None;
-}
-
-/// Return true if LHS implies RHS is true.  Return false if LHS implies RHS is
-/// false.  Otherwise, return None if we can't infer anything.  We expect the
-/// RHS to be an icmp and the LHS to be an 'and' or an 'or' instruction.
-static Optional<bool> isImpliedCondAndOr(const BinaryOperator *LHS,
-                                         const ICmpInst *RHS,
-                                         const DataLayout &DL, bool LHSIsTrue,
-                                         unsigned Depth) {
-  // The LHS must be an 'or' or an 'and' instruction.
-  assert((LHS->getOpcode() == Instruction::And ||
-          LHS->getOpcode() == Instruction::Or) &&
-         "Expected LHS to be 'and' or 'or'.");
-
-  assert(Depth <= MaxDepth && "Hit recursion limit");
-
-  // If the result of an 'or' is false, then we know both legs of the 'or' are
-  // false.  Similarly, if the result of an 'and' is true, then we know both
-  // legs of the 'and' are true.
-  Value *ALHS, *ARHS;
-  if ((!LHSIsTrue && match(LHS, m_Or(m_Value(ALHS), m_Value(ARHS)))) ||
-      (LHSIsTrue && match(LHS, m_And(m_Value(ALHS), m_Value(ARHS))))) {
-    // FIXME: Make this non-recursion.
-    if (Optional<bool> Implication =
-            isImpliedCondition(ALHS, RHS, DL, LHSIsTrue, Depth + 1))
-      return Implication;
-    if (Optional<bool> Implication =
-            isImpliedCondition(ARHS, RHS, DL, LHSIsTrue, Depth + 1))
-      return Implication;
-    return None;
-  }
-  return None;
-}
-
-Optional<bool> llvm::isImpliedCondition(const Value *LHS, const Value *RHS,
-                                        const DataLayout &DL, bool LHSIsTrue,
-                                        unsigned Depth) {
-  // Bail out when we hit the limit.
-  if (Depth == MaxDepth)
-    return None;
-
-  // A mismatch occurs when we compare a scalar cmp to a vector cmp, for
-  // example.
-  if (LHS->getType() != RHS->getType())
-    return None;
-
-  Type *OpTy = LHS->getType();
-  assert(OpTy->isIntOrIntVectorTy(1) && "Expected integer type only!");
-
-  // LHS ==> RHS by definition
-  if (LHS == RHS)
-    return LHSIsTrue;
-
-  // FIXME: Extending the code below to handle vectors.
-  if (OpTy->isVectorTy())
-    return None;
-
-  assert(OpTy->isIntegerTy(1) && "implied by above");
-
-  // Both LHS and RHS are icmps.
-  const ICmpInst *LHSCmp = dyn_cast<ICmpInst>(LHS);
-  const ICmpInst *RHSCmp = dyn_cast<ICmpInst>(RHS);
-  if (LHSCmp && RHSCmp)
-    return isImpliedCondICmps(LHSCmp, RHSCmp, DL, LHSIsTrue, Depth);
-
-  // The LHS should be an 'or' or an 'and' instruction.  We expect the RHS to be
-  // an icmp. FIXME: Add support for and/or on the RHS.
-  const BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(LHS);
-  if (LHSBO && RHSCmp) {
-    if ((LHSBO->getOpcode() == Instruction::And ||
-         LHSBO->getOpcode() == Instruction::Or))
-      return isImpliedCondAndOr(LHSBO, RHSCmp, DL, LHSIsTrue, Depth);
-  }
-  return None;
-}
-
-Optional<bool> llvm::isImpliedByDomCondition(const Value *Cond,
-                                             const Instruction *ContextI,
-                                             const DataLayout &DL) {
-  assert(Cond->getType()->isIntOrIntVectorTy(1) && "Condition must be bool");
-  if (!ContextI || !ContextI->getParent())
-    return None;
-
-  // TODO: This is a poor/cheap way to determine dominance. Should we use a
-  // dominator tree (eg, from a SimplifyQuery) instead?
-  const BasicBlock *ContextBB = ContextI->getParent();
-  const BasicBlock *PredBB = ContextBB->getSinglePredecessor();
-  if (!PredBB)
-    return None;
-
-  // We need a conditional branch in the predecessor.
-  Value *PredCond;
-  BasicBlock *TrueBB, *FalseBB;
-  if (!match(PredBB->getTerminator(), m_Br(m_Value(PredCond), TrueBB, FalseBB)))
-    return None;
-
-  // The branch should get simplified. Don't bother simplifying this condition.
-  if (TrueBB == FalseBB)
-    return None;
-
-  assert((TrueBB == ContextBB || FalseBB == ContextBB) &&
-         "Predecessor block does not point to successor?");
-
-  // Is this condition implied by the predecessor condition?
-  bool CondIsTrue = TrueBB == ContextBB;
-  return isImpliedCondition(PredCond, Cond, DL, CondIsTrue);
-}