Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 2053 deletions

diff --git a/gnu/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/gnu/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
deleted file mode 100644
index faf58a08976..00000000000
--- a/gnu/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ /dev/null
@@ -1,2053 +0,0 @@
-//===- InstCombineSelect.cpp ----------------------------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements the visitSelect function.
-//
-//===----------------------------------------------------------------------===//
-
-#include "InstCombineInternal.h"
-#include "llvm/ADT/APInt.h"
-#include "llvm/ADT/Optional.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/Analysis/AssumptionCache.h"
-#include "llvm/Analysis/CmpInstAnalysis.h"
-#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/Constant.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/IRBuilder.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/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/ErrorHandling.h"
-#include "llvm/Support/KnownBits.h"
-#include "llvm/Transforms/InstCombine/InstCombineWorklist.h"
-#include <cassert>
-#include <utility>
-
-using namespace llvm;
-using namespace PatternMatch;
-
-#define DEBUG_TYPE "instcombine"
-
-static Value *createMinMax(InstCombiner::BuilderTy &Builder,
-                           SelectPatternFlavor SPF, Value *A, Value *B) {
-  CmpInst::Predicate Pred = getMinMaxPred(SPF);
-  assert(CmpInst::isIntPredicate(Pred) && "Expected integer predicate");
-  return Builder.CreateSelect(Builder.CreateICmp(Pred, A, B), A, B);
-}
-
-/// Replace a select operand based on an equality comparison with the identity
-/// constant of a binop.
-static Instruction *foldSelectBinOpIdentity(SelectInst &Sel,
-                                            const TargetLibraryInfo &TLI) {
-  // The select condition must be an equality compare with a constant operand.
-  Value *X;
-  Constant *C;
-  CmpInst::Predicate Pred;
-  if (!match(Sel.getCondition(), m_Cmp(Pred, m_Value(X), m_Constant(C))))
-    return nullptr;
-
-  bool IsEq;
-  if (ICmpInst::isEquality(Pred))
-    IsEq = Pred == ICmpInst::ICMP_EQ;
-  else if (Pred == FCmpInst::FCMP_OEQ)
-    IsEq = true;
-  else if (Pred == FCmpInst::FCMP_UNE)
-    IsEq = false;
-  else
-    return nullptr;
-
-  // A select operand must be a binop.
-  BinaryOperator *BO;
-  if (!match(Sel.getOperand(IsEq ? 1 : 2), m_BinOp(BO)))
-    return nullptr;
-
-  // The compare constant must be the identity constant for that binop.
-  // If this a floating-point compare with 0.0, any zero constant will do.
-  Type *Ty = BO->getType();
-  Constant *IdC = ConstantExpr::getBinOpIdentity(BO->getOpcode(), Ty, true);
-  if (IdC != C) {
-    if (!IdC || !CmpInst::isFPPredicate(Pred))
-      return nullptr;
-    if (!match(IdC, m_AnyZeroFP()) || !match(C, m_AnyZeroFP()))
-      return nullptr;
-  }
-
-  // Last, match the compare variable operand with a binop operand.
-  Value *Y;
-  if (!BO->isCommutative() && !match(BO, m_BinOp(m_Value(Y), m_Specific(X))))
-    return nullptr;
-  if (!match(BO, m_c_BinOp(m_Value(Y), m_Specific(X))))
-    return nullptr;
-
-  // +0.0 compares equal to -0.0, and so it does not behave as required for this
-  // transform. Bail out if we can not exclude that possibility.
-  if (isa<FPMathOperator>(BO))
-    if (!BO->hasNoSignedZeros() && !CannotBeNegativeZero(Y, &TLI))
-      return nullptr;
-
-  // BO = binop Y, X
-  // S = { select (cmp eq X, C), BO, ? } or { select (cmp ne X, C), ?, BO }
-  // =>
-  // S = { select (cmp eq X, C),  Y, ? } or { select (cmp ne X, C), ?,  Y }
-  Sel.setOperand(IsEq ? 1 : 2, Y);
-  return &Sel;
-}
-
-/// This folds:
-///  select (icmp eq (and X, C1)), TC, FC
-///    iff C1 is a power 2 and the difference between TC and FC is a power-of-2.
-/// To something like:
-///  (shr (and (X, C1)), (log2(C1) - log2(TC-FC))) + FC
-/// Or:
-///  (shl (and (X, C1)), (log2(TC-FC) - log2(C1))) + FC
-/// With some variations depending if FC is larger than TC, or the shift
-/// isn't needed, or the bit widths don't match.
-static Value *foldSelectICmpAnd(SelectInst &Sel, ICmpInst *Cmp,
-                                InstCombiner::BuilderTy &Builder) {
-  const APInt *SelTC, *SelFC;
-  if (!match(Sel.getTrueValue(), m_APInt(SelTC)) ||
-      !match(Sel.getFalseValue(), m_APInt(SelFC)))
-    return nullptr;
-
-  // If this is a vector select, we need a vector compare.
-  Type *SelType = Sel.getType();
-  if (SelType->isVectorTy() != Cmp->getType()->isVectorTy())
-    return nullptr;
-
-  Value *V;
-  APInt AndMask;
-  bool CreateAnd = false;
-  ICmpInst::Predicate Pred = Cmp->getPredicate();
-  if (ICmpInst::isEquality(Pred)) {
-    if (!match(Cmp->getOperand(1), m_Zero()))
-      return nullptr;
-
-    V = Cmp->getOperand(0);
-    const APInt *AndRHS;
-    if (!match(V, m_And(m_Value(), m_Power2(AndRHS))))
-      return nullptr;
-
-    AndMask = *AndRHS;
-  } else if (decomposeBitTestICmp(Cmp->getOperand(0), Cmp->getOperand(1),
-                                  Pred, V, AndMask)) {
-    assert(ICmpInst::isEquality(Pred) && "Not equality test?");
-    if (!AndMask.isPowerOf2())
-      return nullptr;
-
-    CreateAnd = true;
-  } else {
-    return nullptr;
-  }
-
-  // In general, when both constants are non-zero, we would need an offset to
-  // replace the select. This would require more instructions than we started
-  // with. But there's one special-case that we handle here because it can
-  // simplify/reduce the instructions.
-  APInt TC = *SelTC;
-  APInt FC = *SelFC;
-  if (!TC.isNullValue() && !FC.isNullValue()) {
-    // If the select constants differ by exactly one bit and that's the same
-    // bit that is masked and checked by the select condition, the select can
-    // be replaced by bitwise logic to set/clear one bit of the constant result.
-    if (TC.getBitWidth() != AndMask.getBitWidth() || (TC ^ FC) != AndMask)
-      return nullptr;
-    if (CreateAnd) {
-      // If we have to create an 'and', then we must kill the cmp to not
-      // increase the instruction count.
-      if (!Cmp->hasOneUse())
-        return nullptr;
-      V = Builder.CreateAnd(V, ConstantInt::get(SelType, AndMask));
-    }
-    bool ExtraBitInTC = TC.ugt(FC);
-    if (Pred == ICmpInst::ICMP_EQ) {
-      // If the masked bit in V is clear, clear or set the bit in the result:
-      // (V & AndMaskC) == 0 ? TC : FC --> (V & AndMaskC) ^ TC
-      // (V & AndMaskC) == 0 ? TC : FC --> (V & AndMaskC) | TC
-      Constant *C = ConstantInt::get(SelType, TC);
-      return ExtraBitInTC ? Builder.CreateXor(V, C) : Builder.CreateOr(V, C);
-    }
-    if (Pred == ICmpInst::ICMP_NE) {
-      // If the masked bit in V is set, set or clear the bit in the result:
-      // (V & AndMaskC) != 0 ? TC : FC --> (V & AndMaskC) | FC
-      // (V & AndMaskC) != 0 ? TC : FC --> (V & AndMaskC) ^ FC
-      Constant *C = ConstantInt::get(SelType, FC);
-      return ExtraBitInTC ? Builder.CreateOr(V, C) : Builder.CreateXor(V, C);
-    }
-    llvm_unreachable("Only expecting equality predicates");
-  }
-
-  // Make sure one of the select arms is a power-of-2.
-  if (!TC.isPowerOf2() && !FC.isPowerOf2())
-    return nullptr;
-
-  // Determine which shift is needed to transform result of the 'and' into the
-  // desired result.
-  const APInt &ValC = !TC.isNullValue() ? TC : FC;
-  unsigned ValZeros = ValC.logBase2();
-  unsigned AndZeros = AndMask.logBase2();
-
-  // Insert the 'and' instruction on the input to the truncate.
-  if (CreateAnd)
-    V = Builder.CreateAnd(V, ConstantInt::get(V->getType(), AndMask));
-
-  // If types don't match, we can still convert the select by introducing a zext
-  // or a trunc of the 'and'.
-  if (ValZeros > AndZeros) {
-    V = Builder.CreateZExtOrTrunc(V, SelType);
-    V = Builder.CreateShl(V, ValZeros - AndZeros);
-  } else if (ValZeros < AndZeros) {
-    V = Builder.CreateLShr(V, AndZeros - ValZeros);
-    V = Builder.CreateZExtOrTrunc(V, SelType);
-  } else {
-    V = Builder.CreateZExtOrTrunc(V, SelType);
-  }
-
-  // Okay, now we know that everything is set up, we just don't know whether we
-  // have a icmp_ne or icmp_eq and whether the true or false val is the zero.
-  bool ShouldNotVal = !TC.isNullValue();
-  ShouldNotVal ^= Pred == ICmpInst::ICMP_NE;
-  if (ShouldNotVal)
-    V = Builder.CreateXor(V, ValC);
-
-  return V;
-}
-
-/// We want to turn code that looks like this:
-///   %C = or %A, %B
-///   %D = select %cond, %C, %A
-/// into:
-///   %C = select %cond, %B, 0
-///   %D = or %A, %C
-///
-/// Assuming that the specified instruction is an operand to the select, return
-/// a bitmask indicating which operands of this instruction are foldable if they
-/// equal the other incoming value of the select.
-static unsigned getSelectFoldableOperands(BinaryOperator *I) {
-  switch (I->getOpcode()) {
-  case Instruction::Add:
-  case Instruction::Mul:
-  case Instruction::And:
-  case Instruction::Or:
-  case Instruction::Xor:
-    return 3;              // Can fold through either operand.
-  case Instruction::Sub:   // Can only fold on the amount subtracted.
-  case Instruction::Shl:   // Can only fold on the shift amount.
-  case Instruction::LShr:
-  case Instruction::AShr:
-    return 1;
-  default:
-    return 0;              // Cannot fold
-  }
-}
-
-/// For the same transformation as the previous function, return the identity
-/// constant that goes into the select.
-static APInt getSelectFoldableConstant(BinaryOperator *I) {
-  switch (I->getOpcode()) {
-  default: llvm_unreachable("This cannot happen!");
-  case Instruction::Add:
-  case Instruction::Sub:
-  case Instruction::Or:
-  case Instruction::Xor:
-  case Instruction::Shl:
-  case Instruction::LShr:
-  case Instruction::AShr:
-    return APInt::getNullValue(I->getType()->getScalarSizeInBits());
-  case Instruction::And:
-    return APInt::getAllOnesValue(I->getType()->getScalarSizeInBits());
-  case Instruction::Mul:
-    return APInt(I->getType()->getScalarSizeInBits(), 1);
-  }
-}
-
-/// We have (select c, TI, FI), and we know that TI and FI have the same opcode.
-Instruction *InstCombiner::foldSelectOpOp(SelectInst &SI, Instruction *TI,
-                                          Instruction *FI) {
-  // Don't break up min/max patterns. The hasOneUse checks below prevent that
-  // for most cases, but vector min/max with bitcasts can be transformed. If the
-  // one-use restrictions are eased for other patterns, we still don't want to
-  // obfuscate min/max.
-  if ((match(&SI, m_SMin(m_Value(), m_Value())) ||
-       match(&SI, m_SMax(m_Value(), m_Value())) ||
-       match(&SI, m_UMin(m_Value(), m_Value())) ||
-       match(&SI, m_UMax(m_Value(), m_Value()))))
-    return nullptr;
-
-  // If this is a cast from the same type, merge.
-  if (TI->getNumOperands() == 1 && TI->isCast()) {
-    Type *FIOpndTy = FI->getOperand(0)->getType();
-    if (TI->getOperand(0)->getType() != FIOpndTy)
-      return nullptr;
-
-    // The select condition may be a vector. We may only change the operand
-    // type if the vector width remains the same (and matches the condition).
-    Type *CondTy = SI.getCondition()->getType();
-    if (CondTy->isVectorTy()) {
-      if (!FIOpndTy->isVectorTy())
-        return nullptr;
-      if (CondTy->getVectorNumElements() != FIOpndTy->getVectorNumElements())
-        return nullptr;
-
-      // TODO: If the backend knew how to deal with casts better, we could
-      // remove this limitation. For now, there's too much potential to create
-      // worse codegen by promoting the select ahead of size-altering casts
-      // (PR28160).
-      //
-      // Note that ValueTracking's matchSelectPattern() looks through casts
-      // without checking 'hasOneUse' when it matches min/max patterns, so this
-      // transform may end up happening anyway.
-      if (TI->getOpcode() != Instruction::BitCast &&
-          (!TI->hasOneUse() || !FI->hasOneUse()))
-        return nullptr;
-    } else if (!TI->hasOneUse() || !FI->hasOneUse()) {
-      // TODO: The one-use restrictions for a scalar select could be eased if
-      // the fold of a select in visitLoadInst() was enhanced to match a pattern
-      // that includes a cast.
-      return nullptr;
-    }
-
-    // Fold this by inserting a select from the input values.
-    Value *NewSI =
-        Builder.CreateSelect(SI.getCondition(), TI->getOperand(0),
-                             FI->getOperand(0), SI.getName() + ".v", &SI);
-    return CastInst::Create(Instruction::CastOps(TI->getOpcode()), NewSI,
-                            TI->getType());
-  }
-
-  // Only handle binary operators (including two-operand getelementptr) with
-  // one-use here. As with the cast case above, it may be possible to relax the
-  // one-use constraint, but that needs be examined carefully since it may not
-  // reduce the total number of instructions.
-  if (TI->getNumOperands() != 2 || FI->getNumOperands() != 2 ||
-      (!isa<BinaryOperator>(TI) && !isa<GetElementPtrInst>(TI)) ||
-      !TI->hasOneUse() || !FI->hasOneUse())
-    return nullptr;
-
-  // Figure out if the operations have any operands in common.
-  Value *MatchOp, *OtherOpT, *OtherOpF;
-  bool MatchIsOpZero;
-  if (TI->getOperand(0) == FI->getOperand(0)) {
-    MatchOp  = TI->getOperand(0);
-    OtherOpT = TI->getOperand(1);
-    OtherOpF = FI->getOperand(1);
-    MatchIsOpZero = true;
-  } else if (TI->getOperand(1) == FI->getOperand(1)) {
-    MatchOp  = TI->getOperand(1);
-    OtherOpT = TI->getOperand(0);
-    OtherOpF = FI->getOperand(0);
-    MatchIsOpZero = false;
-  } else if (!TI->isCommutative()) {
-    return nullptr;
-  } else if (TI->getOperand(0) == FI->getOperand(1)) {
-    MatchOp  = TI->getOperand(0);
-    OtherOpT = TI->getOperand(1);
-    OtherOpF = FI->getOperand(0);
-    MatchIsOpZero = true;
-  } else if (TI->getOperand(1) == FI->getOperand(0)) {
-    MatchOp  = TI->getOperand(1);
-    OtherOpT = TI->getOperand(0);
-    OtherOpF = FI->getOperand(1);
-    MatchIsOpZero = true;
-  } else {
-    return nullptr;
-  }
-
-  // If the select condition is a vector, the operands of the original select's
-  // operands also must be vectors. This may not be the case for getelementptr
-  // for example.
-  if (SI.getCondition()->getType()->isVectorTy() &&
-      (!OtherOpT->getType()->isVectorTy() ||
-       !OtherOpF->getType()->isVectorTy()))
-    return nullptr;
-
-  // If we reach here, they do have operations in common.
-  Value *NewSI = Builder.CreateSelect(SI.getCondition(), OtherOpT, OtherOpF,
-                                      SI.getName() + ".v", &SI);
-  Value *Op0 = MatchIsOpZero ? MatchOp : NewSI;
-  Value *Op1 = MatchIsOpZero ? NewSI : MatchOp;
-  if (auto *BO = dyn_cast<BinaryOperator>(TI)) {
-    BinaryOperator *NewBO = BinaryOperator::Create(BO->getOpcode(), Op0, Op1);
-    NewBO->copyIRFlags(TI);
-    NewBO->andIRFlags(FI);
-    return NewBO;
-  }
-  if (auto *TGEP = dyn_cast<GetElementPtrInst>(TI)) {
-    auto *FGEP = cast<GetElementPtrInst>(FI);
-    Type *ElementType = TGEP->getResultElementType();
-    return TGEP->isInBounds() && FGEP->isInBounds()
-               ? GetElementPtrInst::CreateInBounds(ElementType, Op0, {Op1})
-               : GetElementPtrInst::Create(ElementType, Op0, {Op1});
-  }
-  llvm_unreachable("Expected BinaryOperator or GEP");
-  return nullptr;
-}
-
-static bool isSelect01(const APInt &C1I, const APInt &C2I) {
-  if (!C1I.isNullValue() && !C2I.isNullValue()) // One side must be zero.
-    return false;
-  return C1I.isOneValue() || C1I.isAllOnesValue() ||
-         C2I.isOneValue() || C2I.isAllOnesValue();
-}
-
-/// Try to fold the select into one of the operands to allow further
-/// optimization.
-Instruction *InstCombiner::foldSelectIntoOp(SelectInst &SI, Value *TrueVal,
-                                            Value *FalseVal) {
-  // See the comment above GetSelectFoldableOperands for a description of the
-  // transformation we are doing here.
-  if (auto *TVI = dyn_cast<BinaryOperator>(TrueVal)) {
-    if (TVI->hasOneUse() && !isa<Constant>(FalseVal)) {
-      if (unsigned SFO = getSelectFoldableOperands(TVI)) {
-        unsigned OpToFold = 0;
-        if ((SFO & 1) && FalseVal == TVI->getOperand(0)) {
-          OpToFold = 1;
-        } else if ((SFO & 2) && FalseVal == TVI->getOperand(1)) {
-          OpToFold = 2;
-        }
-
-        if (OpToFold) {
-          APInt CI = getSelectFoldableConstant(TVI);
-          Value *OOp = TVI->getOperand(2-OpToFold);
-          // Avoid creating select between 2 constants unless it's selecting
-          // between 0, 1 and -1.
-          const APInt *OOpC;
-          bool OOpIsAPInt = match(OOp, m_APInt(OOpC));
-          if (!isa<Constant>(OOp) || (OOpIsAPInt && isSelect01(CI, *OOpC))) {
-            Value *C = ConstantInt::get(OOp->getType(), CI);
-            Value *NewSel = Builder.CreateSelect(SI.getCondition(), OOp, C);
-            NewSel->takeName(TVI);
-            BinaryOperator *BO = BinaryOperator::Create(TVI->getOpcode(),
-                                                        FalseVal, NewSel);
-            BO->copyIRFlags(TVI);
-            return BO;
-          }
-        }
-      }
-    }
-  }
-
-  if (auto *FVI = dyn_cast<BinaryOperator>(FalseVal)) {
-    if (FVI->hasOneUse() && !isa<Constant>(TrueVal)) {
-      if (unsigned SFO = getSelectFoldableOperands(FVI)) {
-        unsigned OpToFold = 0;
-        if ((SFO & 1) && TrueVal == FVI->getOperand(0)) {
-          OpToFold = 1;
-        } else if ((SFO & 2) && TrueVal == FVI->getOperand(1)) {
-          OpToFold = 2;
-        }
-
-        if (OpToFold) {
-          APInt CI = getSelectFoldableConstant(FVI);
-          Value *OOp = FVI->getOperand(2-OpToFold);
-          // Avoid creating select between 2 constants unless it's selecting
-          // between 0, 1 and -1.
-          const APInt *OOpC;
-          bool OOpIsAPInt = match(OOp, m_APInt(OOpC));
-          if (!isa<Constant>(OOp) || (OOpIsAPInt && isSelect01(CI, *OOpC))) {
-            Value *C = ConstantInt::get(OOp->getType(), CI);
-            Value *NewSel = Builder.CreateSelect(SI.getCondition(), C, OOp);
-            NewSel->takeName(FVI);
-            BinaryOperator *BO = BinaryOperator::Create(FVI->getOpcode(),
-                                                        TrueVal, NewSel);
-            BO->copyIRFlags(FVI);
-            return BO;
-          }
-        }
-      }
-    }
-  }
-
-  return nullptr;
-}
-
-/// We want to turn:
-///   (select (icmp eq (and X, Y), 0), (and (lshr X, Z), 1), 1)
-/// into:
-///   zext (icmp ne i32 (and X, (or Y, (shl 1, Z))), 0)
-/// Note:
-///   Z may be 0 if lshr is missing.
-/// Worst-case scenario is that we will replace 5 instructions with 5 different
-/// instructions, but we got rid of select.
-static Instruction *foldSelectICmpAndAnd(Type *SelType, const ICmpInst *Cmp,
-                                         Value *TVal, Value *FVal,
-                                         InstCombiner::BuilderTy &Builder) {
-  if (!(Cmp->hasOneUse() && Cmp->getOperand(0)->hasOneUse() &&
-        Cmp->getPredicate() == ICmpInst::ICMP_EQ &&
-        match(Cmp->getOperand(1), m_Zero()) && match(FVal, m_One())))
-    return nullptr;
-
-  // The TrueVal has general form of:  and %B, 1
-  Value *B;
-  if (!match(TVal, m_OneUse(m_And(m_Value(B), m_One()))))
-    return nullptr;
-
-  // Where %B may be optionally shifted:  lshr %X, %Z.
-  Value *X, *Z;
-  const bool HasShift = match(B, m_OneUse(m_LShr(m_Value(X), m_Value(Z))));
-  if (!HasShift)
-    X = B;
-
-  Value *Y;
-  if (!match(Cmp->getOperand(0), m_c_And(m_Specific(X), m_Value(Y))))
-    return nullptr;
-
-  // ((X & Y) == 0) ? ((X >> Z) & 1) : 1 --> (X & (Y | (1 << Z))) != 0
-  // ((X & Y) == 0) ? (X & 1) : 1 --> (X & (Y | 1)) != 0
-  Constant *One = ConstantInt::get(SelType, 1);
-  Value *MaskB = HasShift ? Builder.CreateShl(One, Z) : One;
-  Value *FullMask = Builder.CreateOr(Y, MaskB);
-  Value *MaskedX = Builder.CreateAnd(X, FullMask);
-  Value *ICmpNeZero = Builder.CreateIsNotNull(MaskedX);
-  return new ZExtInst(ICmpNeZero, SelType);
-}
-
-/// We want to turn:
-///   (select (icmp eq (and X, C1), 0), Y, (or Y, C2))
-/// into:
-///   (or (shl (and X, C1), C3), Y)
-/// iff:
-///   C1 and C2 are both powers of 2
-/// where:
-///   C3 = Log(C2) - Log(C1)
-///
-/// This transform handles cases where:
-/// 1. The icmp predicate is inverted
-/// 2. The select operands are reversed
-/// 3. The magnitude of C2 and C1 are flipped
-static Value *foldSelectICmpAndOr(const ICmpInst *IC, Value *TrueVal,
-                                  Value *FalseVal,
-                                  InstCombiner::BuilderTy &Builder) {
-  // Only handle integer compares. Also, if this is a vector select, we need a
-  // vector compare.
-  if (!TrueVal->getType()->isIntOrIntVectorTy() ||
-      TrueVal->getType()->isVectorTy() != IC->getType()->isVectorTy())
-    return nullptr;
-
-  Value *CmpLHS = IC->getOperand(0);
-  Value *CmpRHS = IC->getOperand(1);
-
-  Value *V;
-  unsigned C1Log;
-  bool IsEqualZero;
-  bool NeedAnd = false;
-  if (IC->isEquality()) {
-    if (!match(CmpRHS, m_Zero()))
-      return nullptr;
-
-    const APInt *C1;
-    if (!match(CmpLHS, m_And(m_Value(), m_Power2(C1))))
-      return nullptr;
-
-    V = CmpLHS;
-    C1Log = C1->logBase2();
-    IsEqualZero = IC->getPredicate() == ICmpInst::ICMP_EQ;
-  } else if (IC->getPredicate() == ICmpInst::ICMP_SLT ||
-             IC->getPredicate() == ICmpInst::ICMP_SGT) {
-    // We also need to recognize (icmp slt (trunc (X)), 0) and
-    // (icmp sgt (trunc (X)), -1).
-    IsEqualZero = IC->getPredicate() == ICmpInst::ICMP_SGT;
-    if ((IsEqualZero && !match(CmpRHS, m_AllOnes())) ||
-        (!IsEqualZero && !match(CmpRHS, m_Zero())))
-      return nullptr;
-
-    if (!match(CmpLHS, m_OneUse(m_Trunc(m_Value(V)))))
-      return nullptr;
-
-    C1Log = CmpLHS->getType()->getScalarSizeInBits() - 1;
-    NeedAnd = true;
-  } else {
-    return nullptr;
-  }
-
-  const APInt *C2;
-  bool OrOnTrueVal = false;
-  bool OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2)));
-  if (!OrOnFalseVal)
-    OrOnTrueVal = match(TrueVal, m_Or(m_Specific(FalseVal), m_Power2(C2)));
-
-  if (!OrOnFalseVal && !OrOnTrueVal)
-    return nullptr;
-
-  Value *Y = OrOnFalseVal ? TrueVal : FalseVal;
-
-  unsigned C2Log = C2->logBase2();
-
-  bool NeedXor = (!IsEqualZero && OrOnFalseVal) || (IsEqualZero && OrOnTrueVal);
-  bool NeedShift = C1Log != C2Log;
-  bool NeedZExtTrunc = Y->getType()->getScalarSizeInBits() !=
-                       V->getType()->getScalarSizeInBits();
-
-  // Make sure we don't create more instructions than we save.
-  Value *Or = OrOnFalseVal ? FalseVal : TrueVal;
-  if ((NeedShift + NeedXor + NeedZExtTrunc) >
-      (IC->hasOneUse() + Or->hasOneUse()))
-    return nullptr;
-
-  if (NeedAnd) {
-    // Insert the AND instruction on the input to the truncate.
-    APInt C1 = APInt::getOneBitSet(V->getType()->getScalarSizeInBits(), C1Log);
-    V = Builder.CreateAnd(V, ConstantInt::get(V->getType(), C1));
-  }
-
-  if (C2Log > C1Log) {
-    V = Builder.CreateZExtOrTrunc(V, Y->getType());
-    V = Builder.CreateShl(V, C2Log - C1Log);
-  } else if (C1Log > C2Log) {
-    V = Builder.CreateLShr(V, C1Log - C2Log);
-    V = Builder.CreateZExtOrTrunc(V, Y->getType());
-  } else
-    V = Builder.CreateZExtOrTrunc(V, Y->getType());
-
-  if (NeedXor)
-    V = Builder.CreateXor(V, *C2);
-
-  return Builder.CreateOr(V, Y);
-}
-
-/// Transform patterns such as: (a > b) ? a - b : 0
-/// into: ((a > b) ? a : b) - b)
-/// This produces a canonical max pattern that is more easily recognized by the
-/// backend and converted into saturated subtraction instructions if those
-/// exist.
-/// There are 8 commuted/swapped variants of this pattern.
-/// TODO: Also support a - UMIN(a,b) patterns.
-static Value *canonicalizeSaturatedSubtract(const ICmpInst *ICI,
-                                            const Value *TrueVal,
-                                            const Value *FalseVal,
-                                            InstCombiner::BuilderTy &Builder) {
-  ICmpInst::Predicate Pred = ICI->getPredicate();
-  if (!ICmpInst::isUnsigned(Pred))
-    return nullptr;
-
-  // (b > a) ? 0 : a - b -> (b <= a) ? a - b : 0
-  if (match(TrueVal, m_Zero())) {
-    Pred = ICmpInst::getInversePredicate(Pred);
-    std::swap(TrueVal, FalseVal);
-  }
-  if (!match(FalseVal, m_Zero()))
-    return nullptr;
-
-  Value *A = ICI->getOperand(0);
-  Value *B = ICI->getOperand(1);
-  if (Pred == ICmpInst::ICMP_ULE || Pred == ICmpInst::ICMP_ULT) {
-    // (b < a) ? a - b : 0 -> (a > b) ? a - b : 0
-    std::swap(A, B);
-    Pred = ICmpInst::getSwappedPredicate(Pred);
-  }
-
-  assert((Pred == ICmpInst::ICMP_UGE || Pred == ICmpInst::ICMP_UGT) &&
-         "Unexpected isUnsigned predicate!");
-
-  // Account for swapped form of subtraction: ((a > b) ? b - a : 0).
-  bool IsNegative = false;
-  if (match(TrueVal, m_Sub(m_Specific(B), m_Specific(A))))
-    IsNegative = true;
-  else if (!match(TrueVal, m_Sub(m_Specific(A), m_Specific(B))))
-    return nullptr;
-
-  // If sub is used anywhere else, we wouldn't be able to eliminate it
-  // afterwards.
-  if (!TrueVal->hasOneUse())
-    return nullptr;
-
-  // All checks passed, convert to canonical unsigned saturated subtraction
-  // form: sub(max()).
-  // (a > b) ? a - b : 0 -> ((a > b) ? a : b) - b)
-  Value *Max = Builder.CreateSelect(Builder.CreateICmp(Pred, A, B), A, B);
-  return IsNegative ? Builder.CreateSub(B, Max) : Builder.CreateSub(Max, B);
-}
-
-/// Attempt to fold a cttz/ctlz followed by a icmp plus select into a single
-/// call to cttz/ctlz with flag 'is_zero_undef' cleared.
-///
-/// For example, we can fold the following code sequence:
-/// \code
-///   %0 = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
-///   %1 = icmp ne i32 %x, 0
-///   %2 = select i1 %1, i32 %0, i32 32
-/// \code
-///
-/// into:
-///   %0 = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
-static Value *foldSelectCttzCtlz(ICmpInst *ICI, Value *TrueVal, Value *FalseVal,
-                                 InstCombiner::BuilderTy &Builder) {
-  ICmpInst::Predicate Pred = ICI->getPredicate();
-  Value *CmpLHS = ICI->getOperand(0);
-  Value *CmpRHS = ICI->getOperand(1);
-
-  // Check if the condition value compares a value for equality against zero.
-  if (!ICI->isEquality() || !match(CmpRHS, m_Zero()))
-    return nullptr;
-
-  Value *Count = FalseVal;
-  Value *ValueOnZero = TrueVal;
-  if (Pred == ICmpInst::ICMP_NE)
-    std::swap(Count, ValueOnZero);
-
-  // Skip zero extend/truncate.
-  Value *V = nullptr;
-  if (match(Count, m_ZExt(m_Value(V))) ||
-      match(Count, m_Trunc(m_Value(V))))
-    Count = V;
-
-  // Check that 'Count' is a call to intrinsic cttz/ctlz. Also check that the
-  // input to the cttz/ctlz is used as LHS for the compare instruction.
-  if (!match(Count, m_Intrinsic<Intrinsic::cttz>(m_Specific(CmpLHS))) &&
-      !match(Count, m_Intrinsic<Intrinsic::ctlz>(m_Specific(CmpLHS))))
-    return nullptr;
-
-  IntrinsicInst *II = cast<IntrinsicInst>(Count);
-
-  // Check if the value propagated on zero is a constant number equal to the
-  // sizeof in bits of 'Count'.
-  unsigned SizeOfInBits = Count->getType()->getScalarSizeInBits();
-  if (match(ValueOnZero, m_SpecificInt(SizeOfInBits))) {
-    // Explicitly clear the 'undef_on_zero' flag.
-    IntrinsicInst *NewI = cast<IntrinsicInst>(II->clone());
-    NewI->setArgOperand(1, ConstantInt::getFalse(NewI->getContext()));
-    Builder.Insert(NewI);
-    return Builder.CreateZExtOrTrunc(NewI, ValueOnZero->getType());
-  }
-
-  // If the ValueOnZero is not the bitwidth, we can at least make use of the
-  // fact that the cttz/ctlz result will not be used if the input is zero, so
-  // it's okay to relax it to undef for that case.
-  if (II->hasOneUse() && !match(II->getArgOperand(1), m_One()))
-    II->setArgOperand(1, ConstantInt::getTrue(II->getContext()));
-
-  return nullptr;
-}
-
-/// Return true if we find and adjust an icmp+select pattern where the compare
-/// is with a constant that can be incremented or decremented to match the
-/// minimum or maximum idiom.
-static bool adjustMinMax(SelectInst &Sel, ICmpInst &Cmp) {
-  ICmpInst::Predicate Pred = Cmp.getPredicate();
-  Value *CmpLHS = Cmp.getOperand(0);
-  Value *CmpRHS = Cmp.getOperand(1);
-  Value *TrueVal = Sel.getTrueValue();
-  Value *FalseVal = Sel.getFalseValue();
-
-  // We may move or edit the compare, so make sure the select is the only user.
-  const APInt *CmpC;
-  if (!Cmp.hasOneUse() || !match(CmpRHS, m_APInt(CmpC)))
-    return false;
-
-  // These transforms only work for selects of integers or vector selects of
-  // integer vectors.
-  Type *SelTy = Sel.getType();
-  auto *SelEltTy = dyn_cast<IntegerType>(SelTy->getScalarType());
-  if (!SelEltTy || SelTy->isVectorTy() != Cmp.getType()->isVectorTy())
-    return false;
-
-  Constant *AdjustedRHS;
-  if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_SGT)
-    AdjustedRHS = ConstantInt::get(CmpRHS->getType(), *CmpC + 1);
-  else if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_SLT)
-    AdjustedRHS = ConstantInt::get(CmpRHS->getType(), *CmpC - 1);
-  else
-    return false;
-
-  // X > C ? X : C+1  -->  X < C+1 ? C+1 : X
-  // X < C ? X : C-1  -->  X > C-1 ? C-1 : X
-  if ((CmpLHS == TrueVal && AdjustedRHS == FalseVal) ||
-      (CmpLHS == FalseVal && AdjustedRHS == TrueVal)) {
-    ; // Nothing to do here. Values match without any sign/zero extension.
-  }
-  // Types do not match. Instead of calculating this with mixed types, promote
-  // all to the larger type. This enables scalar evolution to analyze this
-  // expression.
-  else if (CmpRHS->getType()->getScalarSizeInBits() < SelEltTy->getBitWidth()) {
-    Constant *SextRHS = ConstantExpr::getSExt(AdjustedRHS, SelTy);
-
-    // X = sext x; x >s c ? X : C+1 --> X = sext x; X <s C+1 ? C+1 : X
-    // X = sext x; x <s c ? X : C-1 --> X = sext x; X >s C-1 ? C-1 : X
-    // X = sext x; x >u c ? X : C+1 --> X = sext x; X <u C+1 ? C+1 : X
-    // X = sext x; x <u c ? X : C-1 --> X = sext x; X >u C-1 ? C-1 : X
-    if (match(TrueVal, m_SExt(m_Specific(CmpLHS))) && SextRHS == FalseVal) {
-      CmpLHS = TrueVal;
-      AdjustedRHS = SextRHS;
-    } else if (match(FalseVal, m_SExt(m_Specific(CmpLHS))) &&
-               SextRHS == TrueVal) {
-      CmpLHS = FalseVal;
-      AdjustedRHS = SextRHS;
-    } else if (Cmp.isUnsigned()) {
-      Constant *ZextRHS = ConstantExpr::getZExt(AdjustedRHS, SelTy);
-      // X = zext x; x >u c ? X : C+1 --> X = zext x; X <u C+1 ? C+1 : X
-      // X = zext x; x <u c ? X : C-1 --> X = zext x; X >u C-1 ? C-1 : X
-      // zext + signed compare cannot be changed:
-      //    0xff <s 0x00, but 0x00ff >s 0x0000
-      if (match(TrueVal, m_ZExt(m_Specific(CmpLHS))) && ZextRHS == FalseVal) {
-        CmpLHS = TrueVal;
-        AdjustedRHS = ZextRHS;
-      } else if (match(FalseVal, m_ZExt(m_Specific(CmpLHS))) &&
-                 ZextRHS == TrueVal) {
-        CmpLHS = FalseVal;
-        AdjustedRHS = ZextRHS;
-      } else {
-        return false;
-      }
-    } else {
-      return false;
-    }
-  } else {
-    return false;
-  }
-
-  Pred = ICmpInst::getSwappedPredicate(Pred);
-  CmpRHS = AdjustedRHS;
-  std::swap(FalseVal, TrueVal);
-  Cmp.setPredicate(Pred);
-  Cmp.setOperand(0, CmpLHS);
-  Cmp.setOperand(1, CmpRHS);
-  Sel.setOperand(1, TrueVal);
-  Sel.setOperand(2, FalseVal);
-  Sel.swapProfMetadata();
-
-  // Move the compare instruction right before the select instruction. Otherwise
-  // the sext/zext value may be defined after the compare instruction uses it.
-  Cmp.moveBefore(&Sel);
-
-  return true;
-}
-
-/// If this is an integer min/max (icmp + select) with a constant operand,
-/// create the canonical icmp for the min/max operation and canonicalize the
-/// constant to the 'false' operand of the select:
-/// select (icmp Pred X, C1), C2, X --> select (icmp Pred' X, C2), X, C2
-/// Note: if C1 != C2, this will change the icmp constant to the existing
-/// constant operand of the select.
-static Instruction *
-canonicalizeMinMaxWithConstant(SelectInst &Sel, ICmpInst &Cmp,
-                               InstCombiner::BuilderTy &Builder) {
-  if (!Cmp.hasOneUse() || !isa<Constant>(Cmp.getOperand(1)))
-    return nullptr;
-
-  // Canonicalize the compare predicate based on whether we have min or max.
-  Value *LHS, *RHS;
-  SelectPatternResult SPR = matchSelectPattern(&Sel, LHS, RHS);
-  if (!SelectPatternResult::isMinOrMax(SPR.Flavor))
-    return nullptr;
-
-  // Is this already canonical?
-  ICmpInst::Predicate CanonicalPred = getMinMaxPred(SPR.Flavor);
-  if (Cmp.getOperand(0) == LHS && Cmp.getOperand(1) == RHS &&
-      Cmp.getPredicate() == CanonicalPred)
-    return nullptr;
-
-  // Create the canonical compare and plug it into the select.
-  Sel.setCondition(Builder.CreateICmp(CanonicalPred, LHS, RHS));
-
-  // If the select operands did not change, we're done.
-  if (Sel.getTrueValue() == LHS && Sel.getFalseValue() == RHS)
-    return &Sel;
-
-  // If we are swapping the select operands, swap the metadata too.
-  assert(Sel.getTrueValue() == RHS && Sel.getFalseValue() == LHS &&
-         "Unexpected results from matchSelectPattern");
-  Sel.setTrueValue(LHS);
-  Sel.setFalseValue(RHS);
-  Sel.swapProfMetadata();
-  return &Sel;
-}
-
-/// There are many select variants for each of ABS/NABS.
-/// In matchSelectPattern(), there are different compare constants, compare
-/// predicates/operands and select operands.
-/// In isKnownNegation(), there are different formats of negated operands.
-/// Canonicalize all these variants to 1 pattern.
-/// This makes CSE more likely.
-static Instruction *canonicalizeAbsNabs(SelectInst &Sel, ICmpInst &Cmp,
-                                        InstCombiner::BuilderTy &Builder) {
-  if (!Cmp.hasOneUse() || !isa<Constant>(Cmp.getOperand(1)))
-    return nullptr;
-
-  // Choose a sign-bit check for the compare (likely simpler for codegen).
-  // ABS:  (X <s 0) ? -X : X
-  // NABS: (X <s 0) ? X : -X
-  Value *LHS, *RHS;
-  SelectPatternFlavor SPF = matchSelectPattern(&Sel, LHS, RHS).Flavor;
-  if (SPF != SelectPatternFlavor::SPF_ABS &&
-      SPF != SelectPatternFlavor::SPF_NABS)
-    return nullptr;
-
-  Value *TVal = Sel.getTrueValue();
-  Value *FVal = Sel.getFalseValue();
-  assert(isKnownNegation(TVal, FVal) &&
-         "Unexpected result from matchSelectPattern");
-
-  // The compare may use the negated abs()/nabs() operand, or it may use
-  // negation in non-canonical form such as: sub A, B.
-  bool CmpUsesNegatedOp = match(Cmp.getOperand(0), m_Neg(m_Specific(TVal))) ||
-                          match(Cmp.getOperand(0), m_Neg(m_Specific(FVal)));
-
-  bool CmpCanonicalized = !CmpUsesNegatedOp &&
-                          match(Cmp.getOperand(1), m_ZeroInt()) &&
-                          Cmp.getPredicate() == ICmpInst::ICMP_SLT;
-  bool RHSCanonicalized = match(RHS, m_Neg(m_Specific(LHS)));
-
-  // Is this already canonical?
-  if (CmpCanonicalized && RHSCanonicalized)
-    return nullptr;
-
-  // If RHS is used by other instructions except compare and select, don't
-  // canonicalize it to not increase the instruction count.
-  if (!(RHS->hasOneUse() || (RHS->hasNUses(2) && CmpUsesNegatedOp)))
-    return nullptr;
-
-  // Create the canonical compare: icmp slt LHS 0.
-  if (!CmpCanonicalized) {
-    Cmp.setPredicate(ICmpInst::ICMP_SLT);
-    Cmp.setOperand(1, ConstantInt::getNullValue(Cmp.getOperand(0)->getType()));
-    if (CmpUsesNegatedOp)
-      Cmp.setOperand(0, LHS);
-  }
-
-  // Create the canonical RHS: RHS = sub (0, LHS).
-  if (!RHSCanonicalized) {
-    assert(RHS->hasOneUse() && "RHS use number is not right");
-    RHS = Builder.CreateNeg(LHS);
-    if (TVal == LHS) {
-      Sel.setFalseValue(RHS);
-      FVal = RHS;
-    } else {
-      Sel.setTrueValue(RHS);
-      TVal = RHS;
-    }
-  }
-
-  // If the select operands do not change, we're done.
-  if (SPF == SelectPatternFlavor::SPF_NABS) {
-    if (TVal == LHS)
-      return &Sel;
-    assert(FVal == LHS && "Unexpected results from matchSelectPattern");
-  } else {
-    if (FVal == LHS)
-      return &Sel;
-    assert(TVal == LHS && "Unexpected results from matchSelectPattern");
-  }
-
-  // We are swapping the select operands, so swap the metadata too.
-  Sel.setTrueValue(FVal);
-  Sel.setFalseValue(TVal);
-  Sel.swapProfMetadata();
-  return &Sel;
-}
-
-/// Visit a SelectInst that has an ICmpInst as its first operand.
-Instruction *InstCombiner::foldSelectInstWithICmp(SelectInst &SI,
-                                                  ICmpInst *ICI) {
-  Value *TrueVal = SI.getTrueValue();
-  Value *FalseVal = SI.getFalseValue();
-
-  if (Instruction *NewSel = canonicalizeMinMaxWithConstant(SI, *ICI, Builder))
-    return NewSel;
-
-  if (Instruction *NewAbs = canonicalizeAbsNabs(SI, *ICI, Builder))
-    return NewAbs;
-
-  bool Changed = adjustMinMax(SI, *ICI);
-
-  if (Value *V = foldSelectICmpAnd(SI, ICI, Builder))
-    return replaceInstUsesWith(SI, V);
-
-  // NOTE: if we wanted to, this is where to detect integer MIN/MAX
-  ICmpInst::Predicate Pred = ICI->getPredicate();
-  Value *CmpLHS = ICI->getOperand(0);
-  Value *CmpRHS = ICI->getOperand(1);
-  if (CmpRHS != CmpLHS && isa<Constant>(CmpRHS)) {
-    if (CmpLHS == TrueVal && Pred == ICmpInst::ICMP_EQ) {
-      // Transform (X == C) ? X : Y -> (X == C) ? C : Y
-      SI.setOperand(1, CmpRHS);
-      Changed = true;
-    } else if (CmpLHS == FalseVal && Pred == ICmpInst::ICMP_NE) {
-      // Transform (X != C) ? Y : X -> (X != C) ? Y : C
-      SI.setOperand(2, CmpRHS);
-      Changed = true;
-    }
-  }
-
-  // FIXME: This code is nearly duplicated in InstSimplify. Using/refactoring
-  // decomposeBitTestICmp() might help.
-  {
-    unsigned BitWidth =
-        DL.getTypeSizeInBits(TrueVal->getType()->getScalarType());
-    APInt MinSignedValue = APInt::getSignedMinValue(BitWidth);
-    Value *X;
-    const APInt *Y, *C;
-    bool TrueWhenUnset;
-    bool IsBitTest = false;
-    if (ICmpInst::isEquality(Pred) &&
-        match(CmpLHS, m_And(m_Value(X), m_Power2(Y))) &&
-        match(CmpRHS, m_Zero())) {
-      IsBitTest = true;
-      TrueWhenUnset = Pred == ICmpInst::ICMP_EQ;
-    } else if (Pred == ICmpInst::ICMP_SLT && match(CmpRHS, m_Zero())) {
-      X = CmpLHS;
-      Y = &MinSignedValue;
-      IsBitTest = true;
-      TrueWhenUnset = false;
-    } else if (Pred == ICmpInst::ICMP_SGT && match(CmpRHS, m_AllOnes())) {
-      X = CmpLHS;
-      Y = &MinSignedValue;
-      IsBitTest = true;
-      TrueWhenUnset = true;
-    }
-    if (IsBitTest) {
-      Value *V = nullptr;
-      // (X & Y) == 0 ? X : X ^ Y  --> X & ~Y
-      if (TrueWhenUnset && TrueVal == X &&
-          match(FalseVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
-        V = Builder.CreateAnd(X, ~(*Y));
-      // (X & Y) != 0 ? X ^ Y : X  --> X & ~Y
-      else if (!TrueWhenUnset && FalseVal == X &&
-               match(TrueVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
-        V = Builder.CreateAnd(X, ~(*Y));
-      // (X & Y) == 0 ? X ^ Y : X  --> X | Y
-      else if (TrueWhenUnset && FalseVal == X &&
-               match(TrueVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
-        V = Builder.CreateOr(X, *Y);
-      // (X & Y) != 0 ? X : X ^ Y  --> X | Y
-      else if (!TrueWhenUnset && TrueVal == X &&
-               match(FalseVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
-        V = Builder.CreateOr(X, *Y);
-
-      if (V)
-        return replaceInstUsesWith(SI, V);
-    }
-  }
-
-  if (Instruction *V =
-          foldSelectICmpAndAnd(SI.getType(), ICI, TrueVal, FalseVal, Builder))
-    return V;
-
-  if (Value *V = foldSelectICmpAndOr(ICI, TrueVal, FalseVal, Builder))
-    return replaceInstUsesWith(SI, V);
-
-  if (Value *V = foldSelectCttzCtlz(ICI, TrueVal, FalseVal, Builder))
-    return replaceInstUsesWith(SI, V);
-
-  if (Value *V = canonicalizeSaturatedSubtract(ICI, TrueVal, FalseVal, Builder))
-    return replaceInstUsesWith(SI, V);
-
-  return Changed ? &SI : nullptr;
-}
-
-/// SI is a select whose condition is a PHI node (but the two may be in
-/// different blocks). See if the true/false values (V) are live in all of the
-/// predecessor blocks of the PHI. For example, cases like this can't be mapped:
-///
-///   X = phi [ C1, BB1], [C2, BB2]
-///   Y = add
-///   Z = select X, Y, 0
-///
-/// because Y is not live in BB1/BB2.
-static bool canSelectOperandBeMappingIntoPredBlock(const Value *V,
-                                                   const SelectInst &SI) {
-  // If the value is a non-instruction value like a constant or argument, it
-  // can always be mapped.
-  const Instruction *I = dyn_cast<Instruction>(V);
-  if (!I) return true;
-
-  // If V is a PHI node defined in the same block as the condition PHI, we can
-  // map the arguments.
-  const PHINode *CondPHI = cast<PHINode>(SI.getCondition());
-
-  if (const PHINode *VP = dyn_cast<PHINode>(I))
-    if (VP->getParent() == CondPHI->getParent())
-      return true;
-
-  // Otherwise, if the PHI and select are defined in the same block and if V is
-  // defined in a different block, then we can transform it.
-  if (SI.getParent() == CondPHI->getParent() &&
-      I->getParent() != CondPHI->getParent())
-    return true;
-
-  // Otherwise we have a 'hard' case and we can't tell without doing more
-  // detailed dominator based analysis, punt.
-  return false;
-}
-
-/// We have an SPF (e.g. a min or max) of an SPF of the form:
-///   SPF2(SPF1(A, B), C)
-Instruction *InstCombiner::foldSPFofSPF(Instruction *Inner,
-                                        SelectPatternFlavor SPF1,
-                                        Value *A, Value *B,
-                                        Instruction &Outer,
-                                        SelectPatternFlavor SPF2, Value *C) {
-  if (Outer.getType() != Inner->getType())
-    return nullptr;
-
-  if (C == A || C == B) {
-    // MAX(MAX(A, B), B) -> MAX(A, B)
-    // MIN(MIN(a, b), a) -> MIN(a, b)
-    // TODO: This could be done in instsimplify.
-    if (SPF1 == SPF2 && SelectPatternResult::isMinOrMax(SPF1))
-      return replaceInstUsesWith(Outer, Inner);
-
-    // MAX(MIN(a, b), a) -> a
-    // MIN(MAX(a, b), a) -> a
-    // TODO: This could be done in instsimplify.
-    if ((SPF1 == SPF_SMIN && SPF2 == SPF_SMAX) ||
-        (SPF1 == SPF_SMAX && SPF2 == SPF_SMIN) ||
-        (SPF1 == SPF_UMIN && SPF2 == SPF_UMAX) ||
-        (SPF1 == SPF_UMAX && SPF2 == SPF_UMIN))
-      return replaceInstUsesWith(Outer, C);
-  }
-
-  if (SPF1 == SPF2) {
-    const APInt *CB, *CC;
-    if (match(B, m_APInt(CB)) && match(C, m_APInt(CC))) {
-      // MIN(MIN(A, 23), 97) -> MIN(A, 23)
-      // MAX(MAX(A, 97), 23) -> MAX(A, 97)
-      // TODO: This could be done in instsimplify.
-      if ((SPF1 == SPF_UMIN && CB->ule(*CC)) ||
-          (SPF1 == SPF_SMIN && CB->sle(*CC)) ||
-          (SPF1 == SPF_UMAX && CB->uge(*CC)) ||
-          (SPF1 == SPF_SMAX && CB->sge(*CC)))
-        return replaceInstUsesWith(Outer, Inner);
-
-      // MIN(MIN(A, 97), 23) -> MIN(A, 23)
-      // MAX(MAX(A, 23), 97) -> MAX(A, 97)
-      if ((SPF1 == SPF_UMIN && CB->ugt(*CC)) ||
-          (SPF1 == SPF_SMIN && CB->sgt(*CC)) ||
-          (SPF1 == SPF_UMAX && CB->ult(*CC)) ||
-          (SPF1 == SPF_SMAX && CB->slt(*CC))) {
-        Outer.replaceUsesOfWith(Inner, A);
-        return &Outer;
-      }
-    }
-  }
-
-  // ABS(ABS(X)) -> ABS(X)
-  // NABS(NABS(X)) -> NABS(X)
-  // TODO: This could be done in instsimplify.
-  if (SPF1 == SPF2 && (SPF1 == SPF_ABS || SPF1 == SPF_NABS)) {
-    return replaceInstUsesWith(Outer, Inner);
-  }
-
-  // ABS(NABS(X)) -> ABS(X)
-  // NABS(ABS(X)) -> NABS(X)
-  if ((SPF1 == SPF_ABS && SPF2 == SPF_NABS) ||
-      (SPF1 == SPF_NABS && SPF2 == SPF_ABS)) {
-    SelectInst *SI = cast<SelectInst>(Inner);
-    Value *NewSI =
-        Builder.CreateSelect(SI->getCondition(), SI->getFalseValue(),
-                             SI->getTrueValue(), SI->getName(), SI);
-    return replaceInstUsesWith(Outer, NewSI);
-  }
-
-  auto IsFreeOrProfitableToInvert =
-      [&](Value *V, Value *&NotV, bool &ElidesXor) {
-    if (match(V, m_Not(m_Value(NotV)))) {
-      // If V has at most 2 uses then we can get rid of the xor operation
-      // entirely.
-      ElidesXor |= !V->hasNUsesOrMore(3);
-      return true;
-    }
-
-    if (IsFreeToInvert(V, !V->hasNUsesOrMore(3))) {
-      NotV = nullptr;
-      return true;
-    }
-
-    return false;
-  };
-
-  Value *NotA, *NotB, *NotC;
-  bool ElidesXor = false;
-
-  // MIN(MIN(~A, ~B), ~C) == ~MAX(MAX(A, B), C)
-  // MIN(MAX(~A, ~B), ~C) == ~MAX(MIN(A, B), C)
-  // MAX(MIN(~A, ~B), ~C) == ~MIN(MAX(A, B), C)
-  // MAX(MAX(~A, ~B), ~C) == ~MIN(MIN(A, B), C)
-  //
-  // This transform is performance neutral if we can elide at least one xor from
-  // the set of three operands, since we'll be tacking on an xor at the very
-  // end.
-  if (SelectPatternResult::isMinOrMax(SPF1) &&
-      SelectPatternResult::isMinOrMax(SPF2) &&
-      IsFreeOrProfitableToInvert(A, NotA, ElidesXor) &&
-      IsFreeOrProfitableToInvert(B, NotB, ElidesXor) &&
-      IsFreeOrProfitableToInvert(C, NotC, ElidesXor) && ElidesXor) {
-    if (!NotA)
-      NotA = Builder.CreateNot(A);
-    if (!NotB)
-      NotB = Builder.CreateNot(B);
-    if (!NotC)
-      NotC = Builder.CreateNot(C);
-
-    Value *NewInner = createMinMax(Builder, getInverseMinMaxFlavor(SPF1), NotA,
-                                   NotB);
-    Value *NewOuter = Builder.CreateNot(
-        createMinMax(Builder, getInverseMinMaxFlavor(SPF2), NewInner, NotC));
-    return replaceInstUsesWith(Outer, NewOuter);
-  }
-
-  return nullptr;
-}
-
-/// Turn select C, (X + Y), (X - Y) --> (X + (select C, Y, (-Y))).
-/// This is even legal for FP.
-static Instruction *foldAddSubSelect(SelectInst &SI,
-                                     InstCombiner::BuilderTy &Builder) {
-  Value *CondVal = SI.getCondition();
-  Value *TrueVal = SI.getTrueValue();
-  Value *FalseVal = SI.getFalseValue();
-  auto *TI = dyn_cast<Instruction>(TrueVal);
-  auto *FI = dyn_cast<Instruction>(FalseVal);
-  if (!TI || !FI || !TI->hasOneUse() || !FI->hasOneUse())
-    return nullptr;
-
-  Instruction *AddOp = nullptr, *SubOp = nullptr;
-  if ((TI->getOpcode() == Instruction::Sub &&
-       FI->getOpcode() == Instruction::Add) ||
-      (TI->getOpcode() == Instruction::FSub &&
-       FI->getOpcode() == Instruction::FAdd)) {
-    AddOp = FI;
-    SubOp = TI;
-  } else if ((FI->getOpcode() == Instruction::Sub &&
-              TI->getOpcode() == Instruction::Add) ||
-             (FI->getOpcode() == Instruction::FSub &&
-              TI->getOpcode() == Instruction::FAdd)) {
-    AddOp = TI;
-    SubOp = FI;
-  }
-
-  if (AddOp) {
-    Value *OtherAddOp = nullptr;
-    if (SubOp->getOperand(0) == AddOp->getOperand(0)) {
-      OtherAddOp = AddOp->getOperand(1);
-    } else if (SubOp->getOperand(0) == AddOp->getOperand(1)) {
-      OtherAddOp = AddOp->getOperand(0);
-    }
-
-    if (OtherAddOp) {
-      // So at this point we know we have (Y -> OtherAddOp):
-      //        select C, (add X, Y), (sub X, Z)
-      Value *NegVal; // Compute -Z
-      if (SI.getType()->isFPOrFPVectorTy()) {
-        NegVal = Builder.CreateFNeg(SubOp->getOperand(1));
-        if (Instruction *NegInst = dyn_cast<Instruction>(NegVal)) {
-          FastMathFlags Flags = AddOp->getFastMathFlags();
-          Flags &= SubOp->getFastMathFlags();
-          NegInst->setFastMathFlags(Flags);
-        }
-      } else {
-        NegVal = Builder.CreateNeg(SubOp->getOperand(1));
-      }
-
-      Value *NewTrueOp = OtherAddOp;
-      Value *NewFalseOp = NegVal;
-      if (AddOp != TI)
-        std::swap(NewTrueOp, NewFalseOp);
-      Value *NewSel = Builder.CreateSelect(CondVal, NewTrueOp, NewFalseOp,
-                                           SI.getName() + ".p", &SI);
-
-      if (SI.getType()->isFPOrFPVectorTy()) {
-        Instruction *RI =
-            BinaryOperator::CreateFAdd(SubOp->getOperand(0), NewSel);
-
-        FastMathFlags Flags = AddOp->getFastMathFlags();
-        Flags &= SubOp->getFastMathFlags();
-        RI->setFastMathFlags(Flags);
-        return RI;
-      } else
-        return BinaryOperator::CreateAdd(SubOp->getOperand(0), NewSel);
-    }
-  }
-  return nullptr;
-}
-
-Instruction *InstCombiner::foldSelectExtConst(SelectInst &Sel) {
-  Constant *C;
-  if (!match(Sel.getTrueValue(), m_Constant(C)) &&
-      !match(Sel.getFalseValue(), m_Constant(C)))
-    return nullptr;
-
-  Instruction *ExtInst;
-  if (!match(Sel.getTrueValue(), m_Instruction(ExtInst)) &&
-      !match(Sel.getFalseValue(), m_Instruction(ExtInst)))
-    return nullptr;
-
-  auto ExtOpcode = ExtInst->getOpcode();
-  if (ExtOpcode != Instruction::ZExt && ExtOpcode != Instruction::SExt)
-    return nullptr;
-
-  // If we are extending from a boolean type or if we can create a select that
-  // has the same size operands as its condition, try to narrow the select.
-  Value *X = ExtInst->getOperand(0);
-  Type *SmallType = X->getType();
-  Value *Cond = Sel.getCondition();
-  auto *Cmp = dyn_cast<CmpInst>(Cond);
-  if (!SmallType->isIntOrIntVectorTy(1) &&
-      (!Cmp || Cmp->getOperand(0)->getType() != SmallType))
-    return nullptr;
-
-  // If the constant is the same after truncation to the smaller type and
-  // extension to the original type, we can narrow the select.
-  Type *SelType = Sel.getType();
-  Constant *TruncC = ConstantExpr::getTrunc(C, SmallType);
-  Constant *ExtC = ConstantExpr::getCast(ExtOpcode, TruncC, SelType);
-  if (ExtC == C) {
-    Value *TruncCVal = cast<Value>(TruncC);
-    if (ExtInst == Sel.getFalseValue())
-      std::swap(X, TruncCVal);
-
-    // select Cond, (ext X), C --> ext(select Cond, X, C')
-    // select Cond, C, (ext X) --> ext(select Cond, C', X)
-    Value *NewSel = Builder.CreateSelect(Cond, X, TruncCVal, "narrow", &Sel);
-    return CastInst::Create(Instruction::CastOps(ExtOpcode), NewSel, SelType);
-  }
-
-  // If one arm of the select is the extend of the condition, replace that arm
-  // with the extension of the appropriate known bool value.
-  if (Cond == X) {
-    if (ExtInst == Sel.getTrueValue()) {
-      // select X, (sext X), C --> select X, -1, C
-      // select X, (zext X), C --> select X,  1, C
-      Constant *One = ConstantInt::getTrue(SmallType);
-      Constant *AllOnesOrOne = ConstantExpr::getCast(ExtOpcode, One, SelType);
-      return SelectInst::Create(Cond, AllOnesOrOne, C, "", nullptr, &Sel);
-    } else {
-      // select X, C, (sext X) --> select X, C, 0
-      // select X, C, (zext X) --> select X, C, 0
-      Constant *Zero = ConstantInt::getNullValue(SelType);
-      return SelectInst::Create(Cond, C, Zero, "", nullptr, &Sel);
-    }
-  }
-
-  return nullptr;
-}
-
-/// Try to transform a vector select with a constant condition vector into a
-/// shuffle for easier combining with other shuffles and insert/extract.
-static Instruction *canonicalizeSelectToShuffle(SelectInst &SI) {
-  Value *CondVal = SI.getCondition();
-  Constant *CondC;
-  if (!CondVal->getType()->isVectorTy() || !match(CondVal, m_Constant(CondC)))
-    return nullptr;
-
-  unsigned NumElts = CondVal->getType()->getVectorNumElements();
-  SmallVector<Constant *, 16> Mask;
-  Mask.reserve(NumElts);
-  Type *Int32Ty = Type::getInt32Ty(CondVal->getContext());
-  for (unsigned i = 0; i != NumElts; ++i) {
-    Constant *Elt = CondC->getAggregateElement(i);
-    if (!Elt)
-      return nullptr;
-
-    if (Elt->isOneValue()) {
-      // If the select condition element is true, choose from the 1st vector.
-      Mask.push_back(ConstantInt::get(Int32Ty, i));
-    } else if (Elt->isNullValue()) {
-      // If the select condition element is false, choose from the 2nd vector.
-      Mask.push_back(ConstantInt::get(Int32Ty, i + NumElts));
-    } else if (isa<UndefValue>(Elt)) {
-      // Undef in a select condition (choose one of the operands) does not mean
-      // the same thing as undef in a shuffle mask (any value is acceptable), so
-      // give up.
-      return nullptr;
-    } else {
-      // Bail out on a constant expression.
-      return nullptr;
-    }
-  }
-
-  return new ShuffleVectorInst(SI.getTrueValue(), SI.getFalseValue(),
-                               ConstantVector::get(Mask));
-}
-
-/// Reuse bitcasted operands between a compare and select:
-/// select (cmp (bitcast C), (bitcast D)), (bitcast' C), (bitcast' D) -->
-/// bitcast (select (cmp (bitcast C), (bitcast D)), (bitcast C), (bitcast D))
-static Instruction *foldSelectCmpBitcasts(SelectInst &Sel,
-                                          InstCombiner::BuilderTy &Builder) {
-  Value *Cond = Sel.getCondition();
-  Value *TVal = Sel.getTrueValue();
-  Value *FVal = Sel.getFalseValue();
-
-  CmpInst::Predicate Pred;
-  Value *A, *B;
-  if (!match(Cond, m_Cmp(Pred, m_Value(A), m_Value(B))))
-    return nullptr;
-
-  // The select condition is a compare instruction. If the select's true/false
-  // values are already the same as the compare operands, there's nothing to do.
-  if (TVal == A || TVal == B || FVal == A || FVal == B)
-    return nullptr;
-
-  Value *C, *D;
-  if (!match(A, m_BitCast(m_Value(C))) || !match(B, m_BitCast(m_Value(D))))
-    return nullptr;
-
-  // select (cmp (bitcast C), (bitcast D)), (bitcast TSrc), (bitcast FSrc)
-  Value *TSrc, *FSrc;
-  if (!match(TVal, m_BitCast(m_Value(TSrc))) ||
-      !match(FVal, m_BitCast(m_Value(FSrc))))
-    return nullptr;
-
-  // If the select true/false values are *different bitcasts* of the same source
-  // operands, make the select operands the same as the compare operands and
-  // cast the result. This is the canonical select form for min/max.
-  Value *NewSel;
-  if (TSrc == C && FSrc == D) {
-    // select (cmp (bitcast C), (bitcast D)), (bitcast' C), (bitcast' D) -->
-    // bitcast (select (cmp A, B), A, B)
-    NewSel = Builder.CreateSelect(Cond, A, B, "", &Sel);
-  } else if (TSrc == D && FSrc == C) {
-    // select (cmp (bitcast C), (bitcast D)), (bitcast' D), (bitcast' C) -->
-    // bitcast (select (cmp A, B), B, A)
-    NewSel = Builder.CreateSelect(Cond, B, A, "", &Sel);
-  } else {
-    return nullptr;
-  }
-  return CastInst::CreateBitOrPointerCast(NewSel, Sel.getType());
-}
-
-/// Try to eliminate select instructions that test the returned flag of cmpxchg
-/// instructions.
-///
-/// If a select instruction tests the returned flag of a cmpxchg instruction and
-/// selects between the returned value of the cmpxchg instruction its compare
-/// operand, the result of the select will always be equal to its false value.
-/// For example:
-///
-///   %0 = cmpxchg i64* %ptr, i64 %compare, i64 %new_value seq_cst seq_cst
-///   %1 = extractvalue { i64, i1 } %0, 1
-///   %2 = extractvalue { i64, i1 } %0, 0
-///   %3 = select i1 %1, i64 %compare, i64 %2
-///   ret i64 %3
-///
-/// The returned value of the cmpxchg instruction (%2) is the original value
-/// located at %ptr prior to any update. If the cmpxchg operation succeeds, %2
-/// must have been equal to %compare. Thus, the result of the select is always
-/// equal to %2, and the code can be simplified to:
-///
-///   %0 = cmpxchg i64* %ptr, i64 %compare, i64 %new_value seq_cst seq_cst
-///   %1 = extractvalue { i64, i1 } %0, 0
-///   ret i64 %1
-///
-static Instruction *foldSelectCmpXchg(SelectInst &SI) {
-  // A helper that determines if V is an extractvalue instruction whose
-  // aggregate operand is a cmpxchg instruction and whose single index is equal
-  // to I. If such conditions are true, the helper returns the cmpxchg
-  // instruction; otherwise, a nullptr is returned.
-  auto isExtractFromCmpXchg = [](Value *V, unsigned I) -> AtomicCmpXchgInst * {
-    auto *Extract = dyn_cast<ExtractValueInst>(V);
-    if (!Extract)
-      return nullptr;
-    if (Extract->getIndices()[0] != I)
-      return nullptr;
-    return dyn_cast<AtomicCmpXchgInst>(Extract->getAggregateOperand());
-  };
-
-  // If the select has a single user, and this user is a select instruction that
-  // we can simplify, skip the cmpxchg simplification for now.
-  if (SI.hasOneUse())
-    if (auto *Select = dyn_cast<SelectInst>(SI.user_back()))
-      if (Select->getCondition() == SI.getCondition())
-        if (Select->getFalseValue() == SI.getTrueValue() ||
-            Select->getTrueValue() == SI.getFalseValue())
-          return nullptr;
-
-  // Ensure the select condition is the returned flag of a cmpxchg instruction.
-  auto *CmpXchg = isExtractFromCmpXchg(SI.getCondition(), 1);
-  if (!CmpXchg)
-    return nullptr;
-
-  // Check the true value case: The true value of the select is the returned
-  // value of the same cmpxchg used by the condition, and the false value is the
-  // cmpxchg instruction's compare operand.
-  if (auto *X = isExtractFromCmpXchg(SI.getTrueValue(), 0))
-    if (X == CmpXchg && X->getCompareOperand() == SI.getFalseValue()) {
-      SI.setTrueValue(SI.getFalseValue());
-      return &SI;
-    }
-
-  // Check the false value case: The false value of the select is the returned
-  // value of the same cmpxchg used by the condition, and the true value is the
-  // cmpxchg instruction's compare operand.
-  if (auto *X = isExtractFromCmpXchg(SI.getFalseValue(), 0))
-    if (X == CmpXchg && X->getCompareOperand() == SI.getTrueValue()) {
-      SI.setTrueValue(SI.getFalseValue());
-      return &SI;
-    }
-
-  return nullptr;
-}
-
-/// Reduce a sequence of min/max with a common operand.
-static Instruction *factorizeMinMaxTree(SelectPatternFlavor SPF, Value *LHS,
-                                        Value *RHS,
-                                        InstCombiner::BuilderTy &Builder) {
-  assert(SelectPatternResult::isMinOrMax(SPF) && "Expected a min/max");
-  // TODO: Allow FP min/max with nnan/nsz.
-  if (!LHS->getType()->isIntOrIntVectorTy())
-    return nullptr;
-
-  // Match 3 of the same min/max ops. Example: umin(umin(), umin()).
-  Value *A, *B, *C, *D;
-  SelectPatternResult L = matchSelectPattern(LHS, A, B);
-  SelectPatternResult R = matchSelectPattern(RHS, C, D);
-  if (SPF != L.Flavor || L.Flavor != R.Flavor)
-    return nullptr;
-
-  // Look for a common operand. The use checks are different than usual because
-  // a min/max pattern typically has 2 uses of each op: 1 by the cmp and 1 by
-  // the select.
-  Value *MinMaxOp = nullptr;
-  Value *ThirdOp = nullptr;
-  if (!LHS->hasNUsesOrMore(3) && RHS->hasNUsesOrMore(3)) {
-    // If the LHS is only used in this chain and the RHS is used outside of it,
-    // reuse the RHS min/max because that will eliminate the LHS.
-    if (D == A || C == A) {
-      // min(min(a, b), min(c, a)) --> min(min(c, a), b)
-      // min(min(a, b), min(a, d)) --> min(min(a, d), b)
-      MinMaxOp = RHS;
-      ThirdOp = B;
-    } else if (D == B || C == B) {
-      // min(min(a, b), min(c, b)) --> min(min(c, b), a)
-      // min(min(a, b), min(b, d)) --> min(min(b, d), a)
-      MinMaxOp = RHS;
-      ThirdOp = A;
-    }
-  } else if (!RHS->hasNUsesOrMore(3)) {
-    // Reuse the LHS. This will eliminate the RHS.
-    if (D == A || D == B) {
-      // min(min(a, b), min(c, a)) --> min(min(a, b), c)
-      // min(min(a, b), min(c, b)) --> min(min(a, b), c)
-      MinMaxOp = LHS;
-      ThirdOp = C;
-    } else if (C == A || C == B) {
-      // min(min(a, b), min(b, d)) --> min(min(a, b), d)
-      // min(min(a, b), min(c, b)) --> min(min(a, b), d)
-      MinMaxOp = LHS;
-      ThirdOp = D;
-    }
-  }
-  if (!MinMaxOp || !ThirdOp)
-    return nullptr;
-
-  CmpInst::Predicate P = getMinMaxPred(SPF);
-  Value *CmpABC = Builder.CreateICmp(P, MinMaxOp, ThirdOp);
-  return SelectInst::Create(CmpABC, MinMaxOp, ThirdOp);
-}
-
-/// Try to reduce a rotate pattern that includes a compare and select into a
-/// funnel shift intrinsic. Example:
-/// rotl32(a, b) --> (b == 0 ? a : ((a >> (32 - b)) | (a << b)))
-///              --> call llvm.fshl.i32(a, a, b)
-static Instruction *foldSelectRotate(SelectInst &Sel) {
-  // The false value of the select must be a rotate of the true value.
-  Value *Or0, *Or1;
-  if (!match(Sel.getFalseValue(), m_OneUse(m_Or(m_Value(Or0), m_Value(Or1)))))
-    return nullptr;
-
-  Value *TVal = Sel.getTrueValue();
-  Value *SA0, *SA1;
-  if (!match(Or0, m_OneUse(m_LogicalShift(m_Specific(TVal), m_Value(SA0)))) ||
-      !match(Or1, m_OneUse(m_LogicalShift(m_Specific(TVal), m_Value(SA1)))))
-    return nullptr;
-
-  auto ShiftOpcode0 = cast<BinaryOperator>(Or0)->getOpcode();
-  auto ShiftOpcode1 = cast<BinaryOperator>(Or1)->getOpcode();
-  if (ShiftOpcode0 == ShiftOpcode1)
-    return nullptr;
-
-  // We have one of these patterns so far:
-  // select ?, TVal, (or (lshr TVal, SA0), (shl TVal, SA1))
-  // select ?, TVal, (or (shl TVal, SA0), (lshr TVal, SA1))
-  // This must be a power-of-2 rotate for a bitmasking transform to be valid.
-  unsigned Width = Sel.getType()->getScalarSizeInBits();
-  if (!isPowerOf2_32(Width))
-    return nullptr;
-
-  // Check the shift amounts to see if they are an opposite pair.
-  Value *ShAmt;
-  if (match(SA1, m_OneUse(m_Sub(m_SpecificInt(Width), m_Specific(SA0)))))
-    ShAmt = SA0;
-  else if (match(SA0, m_OneUse(m_Sub(m_SpecificInt(Width), m_Specific(SA1)))))
-    ShAmt = SA1;
-  else
-    return nullptr;
-
-  // Finally, see if the select is filtering out a shift-by-zero.
-  Value *Cond = Sel.getCondition();
-  ICmpInst::Predicate Pred;
-  if (!match(Cond, m_OneUse(m_ICmp(Pred, m_Specific(ShAmt), m_ZeroInt()))) ||
-      Pred != ICmpInst::ICMP_EQ)
-    return nullptr;
-
-  // This is a rotate that avoids shift-by-bitwidth UB in a suboptimal way.
-  // Convert to funnel shift intrinsic.
-  bool IsFshl = (ShAmt == SA0 && ShiftOpcode0 == BinaryOperator::Shl) ||
-                (ShAmt == SA1 && ShiftOpcode1 == BinaryOperator::Shl);
-  Intrinsic::ID IID = IsFshl ? Intrinsic::fshl : Intrinsic::fshr;
-  Function *F = Intrinsic::getDeclaration(Sel.getModule(), IID, Sel.getType());
-  return IntrinsicInst::Create(F, { TVal, TVal, ShAmt });
-}
-
-Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
-  Value *CondVal = SI.getCondition();
-  Value *TrueVal = SI.getTrueValue();
-  Value *FalseVal = SI.getFalseValue();
-  Type *SelType = SI.getType();
-
-  // FIXME: Remove this workaround when freeze related patches are done.
-  // For select with undef operand which feeds into an equality comparison,
-  // don't simplify it so loop unswitch can know the equality comparison
-  // may have an undef operand. This is a workaround for PR31652 caused by
-  // descrepancy about branch on undef between LoopUnswitch and GVN.
-  if (isa<UndefValue>(TrueVal) || isa<UndefValue>(FalseVal)) {
-    if (llvm::any_of(SI.users(), [&](User *U) {
-          ICmpInst *CI = dyn_cast<ICmpInst>(U);
-          if (CI && CI->isEquality())
-            return true;
-          return false;
-        })) {
-      return nullptr;
-    }
-  }
-
-  if (Value *V = SimplifySelectInst(CondVal, TrueVal, FalseVal,
-                                    SQ.getWithInstruction(&SI)))
-    return replaceInstUsesWith(SI, V);
-
-  if (Instruction *I = canonicalizeSelectToShuffle(SI))
-    return I;
-
-  // Canonicalize a one-use integer compare with a non-canonical predicate by
-  // inverting the predicate and swapping the select operands. This matches a
-  // compare canonicalization for conditional branches.
-  // TODO: Should we do the same for FP compares?
-  CmpInst::Predicate Pred;
-  if (match(CondVal, m_OneUse(m_ICmp(Pred, m_Value(), m_Value()))) &&
-      !isCanonicalPredicate(Pred)) {
-    // Swap true/false values and condition.
-    CmpInst *Cond = cast<CmpInst>(CondVal);
-    Cond->setPredicate(CmpInst::getInversePredicate(Pred));
-    SI.setOperand(1, FalseVal);
-    SI.setOperand(2, TrueVal);
-    SI.swapProfMetadata();
-    Worklist.Add(Cond);
-    return &SI;
-  }
-
-  if (SelType->isIntOrIntVectorTy(1) &&
-      TrueVal->getType() == CondVal->getType()) {
-    if (match(TrueVal, m_One())) {
-      // Change: A = select B, true, C --> A = or B, C
-      return BinaryOperator::CreateOr(CondVal, FalseVal);
-    }
-    if (match(TrueVal, m_Zero())) {
-      // Change: A = select B, false, C --> A = and !B, C
-      Value *NotCond = Builder.CreateNot(CondVal, "not." + CondVal->getName());
-      return BinaryOperator::CreateAnd(NotCond, FalseVal);
-    }
-    if (match(FalseVal, m_Zero())) {
-      // Change: A = select B, C, false --> A = and B, C
-      return BinaryOperator::CreateAnd(CondVal, TrueVal);
-    }
-    if (match(FalseVal, m_One())) {
-      // Change: A = select B, C, true --> A = or !B, C
-      Value *NotCond = Builder.CreateNot(CondVal, "not." + CondVal->getName());
-      return BinaryOperator::CreateOr(NotCond, TrueVal);
-    }
-
-    // select a, a, b  -> a | b
-    // select a, b, a  -> a & b
-    if (CondVal == TrueVal)
-      return BinaryOperator::CreateOr(CondVal, FalseVal);
-    if (CondVal == FalseVal)
-      return BinaryOperator::CreateAnd(CondVal, TrueVal);
-
-    // select a, ~a, b -> (~a) & b
-    // select a, b, ~a -> (~a) | b
-    if (match(TrueVal, m_Not(m_Specific(CondVal))))
-      return BinaryOperator::CreateAnd(TrueVal, FalseVal);
-    if (match(FalseVal, m_Not(m_Specific(CondVal))))
-      return BinaryOperator::CreateOr(TrueVal, FalseVal);
-  }
-
-  // Selecting between two integer or vector splat integer constants?
-  //
-  // Note that we don't handle a scalar select of vectors:
-  // select i1 %c, <2 x i8> <1, 1>, <2 x i8> <0, 0>
-  // because that may need 3 instructions to splat the condition value:
-  // extend, insertelement, shufflevector.
-  if (SelType->isIntOrIntVectorTy() &&
-      CondVal->getType()->isVectorTy() == SelType->isVectorTy()) {
-    // select C, 1, 0 -> zext C to int
-    if (match(TrueVal, m_One()) && match(FalseVal, m_Zero()))
-      return new ZExtInst(CondVal, SelType);
-
-    // select C, -1, 0 -> sext C to int
-    if (match(TrueVal, m_AllOnes()) && match(FalseVal, m_Zero()))
-      return new SExtInst(CondVal, SelType);
-
-    // select C, 0, 1 -> zext !C to int
-    if (match(TrueVal, m_Zero()) && match(FalseVal, m_One())) {
-      Value *NotCond = Builder.CreateNot(CondVal, "not." + CondVal->getName());
-      return new ZExtInst(NotCond, SelType);
-    }
-
-    // select C, 0, -1 -> sext !C to int
-    if (match(TrueVal, m_Zero()) && match(FalseVal, m_AllOnes())) {
-      Value *NotCond = Builder.CreateNot(CondVal, "not." + CondVal->getName());
-      return new SExtInst(NotCond, SelType);
-    }
-  }
-
-  // See if we are selecting two values based on a comparison of the two values.
-  if (FCmpInst *FCI = dyn_cast<FCmpInst>(CondVal)) {
-    if (FCI->getOperand(0) == TrueVal && FCI->getOperand(1) == FalseVal) {
-      // Canonicalize to use ordered comparisons by swapping the select
-      // operands.
-      //
-      // e.g.
-      // (X ugt Y) ? X : Y -> (X ole Y) ? Y : X
-      if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
-        FCmpInst::Predicate InvPred = FCI->getInversePredicate();
-        IRBuilder<>::FastMathFlagGuard FMFG(Builder);
-        Builder.setFastMathFlags(FCI->getFastMathFlags());
-        Value *NewCond = Builder.CreateFCmp(InvPred, TrueVal, FalseVal,
-                                            FCI->getName() + ".inv");
-
-        return SelectInst::Create(NewCond, FalseVal, TrueVal,
-                                  SI.getName() + ".p");
-      }
-
-      // NOTE: if we wanted to, this is where to detect MIN/MAX
-    } else if (FCI->getOperand(0) == FalseVal && FCI->getOperand(1) == TrueVal){
-      // Canonicalize to use ordered comparisons by swapping the select
-      // operands.
-      //
-      // e.g.
-      // (X ugt Y) ? X : Y -> (X ole Y) ? X : Y
-      if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
-        FCmpInst::Predicate InvPred = FCI->getInversePredicate();
-        IRBuilder<>::FastMathFlagGuard FMFG(Builder);
-        Builder.setFastMathFlags(FCI->getFastMathFlags());
-        Value *NewCond = Builder.CreateFCmp(InvPred, FalseVal, TrueVal,
-                                            FCI->getName() + ".inv");
-
-        return SelectInst::Create(NewCond, FalseVal, TrueVal,
-                                  SI.getName() + ".p");
-      }
-
-      // NOTE: if we wanted to, this is where to detect MIN/MAX
-    }
-
-    // Canonicalize select with fcmp to fabs(). -0.0 makes this tricky. We need
-    // fast-math-flags (nsz) or fsub with +0.0 (not fneg) for this to work. We
-    // also require nnan because we do not want to unintentionally change the
-    // sign of a NaN value.
-    Value *X = FCI->getOperand(0);
-    FCmpInst::Predicate Pred = FCI->getPredicate();
-    if (match(FCI->getOperand(1), m_AnyZeroFP()) && FCI->hasNoNaNs()) {
-      // (X <= +/-0.0) ? (0.0 - X) : X --> fabs(X)
-      // (X >  +/-0.0) ? X : (0.0 - X) --> fabs(X)
-      if ((X == FalseVal && Pred == FCmpInst::FCMP_OLE &&
-           match(TrueVal, m_FSub(m_PosZeroFP(), m_Specific(X)))) ||
-          (X == TrueVal && Pred == FCmpInst::FCMP_OGT &&
-           match(FalseVal, m_FSub(m_PosZeroFP(), m_Specific(X))))) {
-        Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, X, FCI);
-        return replaceInstUsesWith(SI, Fabs);
-      }
-      // With nsz:
-      // (X <  +/-0.0) ? -X : X --> fabs(X)
-      // (X <= +/-0.0) ? -X : X --> fabs(X)
-      // (X >  +/-0.0) ? X : -X --> fabs(X)
-      // (X >= +/-0.0) ? X : -X --> fabs(X)
-      if (FCI->hasNoSignedZeros() &&
-          ((X == FalseVal && match(TrueVal, m_FNeg(m_Specific(X))) &&
-            (Pred == FCmpInst::FCMP_OLT || Pred == FCmpInst::FCMP_OLE)) ||
-           (X == TrueVal && match(FalseVal, m_FNeg(m_Specific(X))) &&
-            (Pred == FCmpInst::FCMP_OGT || Pred == FCmpInst::FCMP_OGE)))) {
-        Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, X, FCI);
-        return replaceInstUsesWith(SI, Fabs);
-      }
-    }
-  }
-
-  // See if we are selecting two values based on a comparison of the two values.
-  if (ICmpInst *ICI = dyn_cast<ICmpInst>(CondVal))
-    if (Instruction *Result = foldSelectInstWithICmp(SI, ICI))
-      return Result;
-
-  if (Instruction *Add = foldAddSubSelect(SI, Builder))
-    return Add;
-
-  // Turn (select C, (op X, Y), (op X, Z)) -> (op X, (select C, Y, Z))
-  auto *TI = dyn_cast<Instruction>(TrueVal);
-  auto *FI = dyn_cast<Instruction>(FalseVal);
-  if (TI && FI && TI->getOpcode() == FI->getOpcode())
-    if (Instruction *IV = foldSelectOpOp(SI, TI, FI))
-      return IV;
-
-  if (Instruction *I = foldSelectExtConst(SI))
-    return I;
-
-  // See if we can fold the select into one of our operands.
-  if (SelType->isIntOrIntVectorTy() || SelType->isFPOrFPVectorTy()) {
-    if (Instruction *FoldI = foldSelectIntoOp(SI, TrueVal, FalseVal))
-      return FoldI;
-
-    Value *LHS, *RHS;
-    Instruction::CastOps CastOp;
-    SelectPatternResult SPR = matchSelectPattern(&SI, LHS, RHS, &CastOp);
-    auto SPF = SPR.Flavor;
-    if (SPF) {
-      Value *LHS2, *RHS2;
-      if (SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2).Flavor)
-        if (Instruction *R = foldSPFofSPF(cast<Instruction>(LHS), SPF2, LHS2,
-                                          RHS2, SI, SPF, RHS))
-          return R;
-      if (SelectPatternFlavor SPF2 = matchSelectPattern(RHS, LHS2, RHS2).Flavor)
-        if (Instruction *R = foldSPFofSPF(cast<Instruction>(RHS), SPF2, LHS2,
-                                          RHS2, SI, SPF, LHS))
-          return R;
-      // TODO.
-      // ABS(-X) -> ABS(X)
-    }
-
-    if (SelectPatternResult::isMinOrMax(SPF)) {
-      // Canonicalize so that
-      // - type casts are outside select patterns.
-      // - float clamp is transformed to min/max pattern
-
-      bool IsCastNeeded = LHS->getType() != SelType;
-      Value *CmpLHS = cast<CmpInst>(CondVal)->getOperand(0);
-      Value *CmpRHS = cast<CmpInst>(CondVal)->getOperand(1);
-      if (IsCastNeeded ||
-          (LHS->getType()->isFPOrFPVectorTy() &&
-           ((CmpLHS != LHS && CmpLHS != RHS) ||
-            (CmpRHS != LHS && CmpRHS != RHS)))) {
-        CmpInst::Predicate Pred = getMinMaxPred(SPF, SPR.Ordered);
-
-        Value *Cmp;
-        if (CmpInst::isIntPredicate(Pred)) {
-          Cmp = Builder.CreateICmp(Pred, LHS, RHS);
-        } else {
-          IRBuilder<>::FastMathFlagGuard FMFG(Builder);
-          auto FMF = cast<FPMathOperator>(SI.getCondition())->getFastMathFlags();
-          Builder.setFastMathFlags(FMF);
-          Cmp = Builder.CreateFCmp(Pred, LHS, RHS);
-        }
-
-        Value *NewSI = Builder.CreateSelect(Cmp, LHS, RHS, SI.getName(), &SI);
-        if (!IsCastNeeded)
-          return replaceInstUsesWith(SI, NewSI);
-
-        Value *NewCast = Builder.CreateCast(CastOp, NewSI, SelType);
-        return replaceInstUsesWith(SI, NewCast);
-      }
-
-      // MAX(~a, ~b) -> ~MIN(a, b)
-      // MAX(~a, C)  -> ~MIN(a, ~C)
-      // MIN(~a, ~b) -> ~MAX(a, b)
-      // MIN(~a, C)  -> ~MAX(a, ~C)
-      auto moveNotAfterMinMax = [&](Value *X, Value *Y) -> Instruction * {
-        Value *A;
-        if (match(X, m_Not(m_Value(A))) && !X->hasNUsesOrMore(3) &&
-            !IsFreeToInvert(A, A->hasOneUse()) &&
-            // Passing false to only consider m_Not and constants.
-            IsFreeToInvert(Y, false)) {
-          Value *B = Builder.CreateNot(Y);
-          Value *NewMinMax = createMinMax(Builder, getInverseMinMaxFlavor(SPF),
-                                          A, B);
-          // Copy the profile metadata.
-          if (MDNode *MD = SI.getMetadata(LLVMContext::MD_prof)) {
-            cast<SelectInst>(NewMinMax)->setMetadata(LLVMContext::MD_prof, MD);
-            // Swap the metadata if the operands are swapped.
-            if (X == SI.getFalseValue() && Y == SI.getTrueValue())
-              cast<SelectInst>(NewMinMax)->swapProfMetadata();
-          }
-
-          return BinaryOperator::CreateNot(NewMinMax);
-        }
-
-        return nullptr;
-      };
-
-      if (Instruction *I = moveNotAfterMinMax(LHS, RHS))
-        return I;
-      if (Instruction *I = moveNotAfterMinMax(RHS, LHS))
-        return I;
-
-      if (Instruction *I = factorizeMinMaxTree(SPF, LHS, RHS, Builder))
-        return I;
-    }
-  }
-
-  // See if we can fold the select into a phi node if the condition is a select.
-  if (auto *PN = dyn_cast<PHINode>(SI.getCondition()))
-    // The true/false values have to be live in the PHI predecessor's blocks.
-    if (canSelectOperandBeMappingIntoPredBlock(TrueVal, SI) &&
-        canSelectOperandBeMappingIntoPredBlock(FalseVal, SI))
-      if (Instruction *NV = foldOpIntoPhi(SI, PN))
-        return NV;
-
-  if (SelectInst *TrueSI = dyn_cast<SelectInst>(TrueVal)) {
-    if (TrueSI->getCondition()->getType() == CondVal->getType()) {
-      // select(C, select(C, a, b), c) -> select(C, a, c)
-      if (TrueSI->getCondition() == CondVal) {
-        if (SI.getTrueValue() == TrueSI->getTrueValue())
-          return nullptr;
-        SI.setOperand(1, TrueSI->getTrueValue());
-        return &SI;
-      }
-      // select(C0, select(C1, a, b), b) -> select(C0&C1, a, b)
-      // We choose this as normal form to enable folding on the And and shortening
-      // paths for the values (this helps GetUnderlyingObjects() for example).
-      if (TrueSI->getFalseValue() == FalseVal && TrueSI->hasOneUse()) {
-        Value *And = Builder.CreateAnd(CondVal, TrueSI->getCondition());
-        SI.setOperand(0, And);
-        SI.setOperand(1, TrueSI->getTrueValue());
-        return &SI;
-      }
-    }
-  }
-  if (SelectInst *FalseSI = dyn_cast<SelectInst>(FalseVal)) {
-    if (FalseSI->getCondition()->getType() == CondVal->getType()) {
-      // select(C, a, select(C, b, c)) -> select(C, a, c)
-      if (FalseSI->getCondition() == CondVal) {
-        if (SI.getFalseValue() == FalseSI->getFalseValue())
-          return nullptr;
-        SI.setOperand(2, FalseSI->getFalseValue());
-        return &SI;
-      }
-      // select(C0, a, select(C1, a, b)) -> select(C0|C1, a, b)
-      if (FalseSI->getTrueValue() == TrueVal && FalseSI->hasOneUse()) {
-        Value *Or = Builder.CreateOr(CondVal, FalseSI->getCondition());
-        SI.setOperand(0, Or);
-        SI.setOperand(2, FalseSI->getFalseValue());
-        return &SI;
-      }
-    }
-  }
-
-  auto canMergeSelectThroughBinop = [](BinaryOperator *BO) {
-    // The select might be preventing a division by 0.
-    switch (BO->getOpcode()) {
-    default:
-      return true;
-    case Instruction::SRem:
-    case Instruction::URem:
-    case Instruction::SDiv:
-    case Instruction::UDiv:
-      return false;
-    }
-  };
-
-  // Try to simplify a binop sandwiched between 2 selects with the same
-  // condition.
-  // select(C, binop(select(C, X, Y), W), Z) -> select(C, binop(X, W), Z)
-  BinaryOperator *TrueBO;
-  if (match(TrueVal, m_OneUse(m_BinOp(TrueBO))) &&
-      canMergeSelectThroughBinop(TrueBO)) {
-    if (auto *TrueBOSI = dyn_cast<SelectInst>(TrueBO->getOperand(0))) {
-      if (TrueBOSI->getCondition() == CondVal) {
-        TrueBO->setOperand(0, TrueBOSI->getTrueValue());
-        Worklist.Add(TrueBO);
-        return &SI;
-      }
-    }
-    if (auto *TrueBOSI = dyn_cast<SelectInst>(TrueBO->getOperand(1))) {
-      if (TrueBOSI->getCondition() == CondVal) {
-        TrueBO->setOperand(1, TrueBOSI->getTrueValue());
-        Worklist.Add(TrueBO);
-        return &SI;
-      }
-    }
-  }
-
-  // select(C, Z, binop(select(C, X, Y), W)) -> select(C, Z, binop(Y, W))
-  BinaryOperator *FalseBO;
-  if (match(FalseVal, m_OneUse(m_BinOp(FalseBO))) &&
-      canMergeSelectThroughBinop(FalseBO)) {
-    if (auto *FalseBOSI = dyn_cast<SelectInst>(FalseBO->getOperand(0))) {
-      if (FalseBOSI->getCondition() == CondVal) {
-        FalseBO->setOperand(0, FalseBOSI->getFalseValue());
-        Worklist.Add(FalseBO);
-        return &SI;
-      }
-    }
-    if (auto *FalseBOSI = dyn_cast<SelectInst>(FalseBO->getOperand(1))) {
-      if (FalseBOSI->getCondition() == CondVal) {
-        FalseBO->setOperand(1, FalseBOSI->getFalseValue());
-        Worklist.Add(FalseBO);
-        return &SI;
-      }
-    }
-  }
-
-  Value *NotCond;
-  if (match(CondVal, m_Not(m_Value(NotCond)))) {
-    SI.setOperand(0, NotCond);
-    SI.setOperand(1, FalseVal);
-    SI.setOperand(2, TrueVal);
-    SI.swapProfMetadata();
-    return &SI;
-  }
-
-  if (VectorType *VecTy = dyn_cast<VectorType>(SelType)) {
-    unsigned VWidth = VecTy->getNumElements();
-    APInt UndefElts(VWidth, 0);
-    APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
-    if (Value *V = SimplifyDemandedVectorElts(&SI, AllOnesEltMask, UndefElts)) {
-      if (V != &SI)
-        return replaceInstUsesWith(SI, V);
-      return &SI;
-    }
-  }
-
-  // If we can compute the condition, there's no need for a select.
-  // Like the above fold, we are attempting to reduce compile-time cost by
-  // putting this fold here with limitations rather than in InstSimplify.
-  // The motivation for this call into value tracking is to take advantage of
-  // the assumption cache, so make sure that is populated.
-  if (!CondVal->getType()->isVectorTy() && !AC.assumptions().empty()) {
-    KnownBits Known(1);
-    computeKnownBits(CondVal, Known, 0, &SI);
-    if (Known.One.isOneValue())
-      return replaceInstUsesWith(SI, TrueVal);
-    if (Known.Zero.isOneValue())
-      return replaceInstUsesWith(SI, FalseVal);
-  }
-
-  if (Instruction *BitCastSel = foldSelectCmpBitcasts(SI, Builder))
-    return BitCastSel;
-
-  // Simplify selects that test the returned flag of cmpxchg instructions.
-  if (Instruction *Select = foldSelectCmpXchg(SI))
-    return Select;
-
-  if (Instruction *Select = foldSelectBinOpIdentity(SI, TLI))
-    return Select;
-
-  if (Instruction *Rot = foldSelectRotate(SI))
-    return Rot;
-
-  return nullptr;
-}