Members/tobaru/cbc/CbC_llvm: lib/Transforms/InstCombine/InstCombineAddSub.cpp comparison

comparison lib/Transforms/InstCombine/InstCombineAddSub.cpp @ 80:67baa08a3894

update to LLVM 3.6

author	Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
date	Thu, 25 Sep 2014 16:56:18 +0900
parents	54457678186b
children	60c9769439b8

comparison

equal deleted inserted replaced

-:9e74acfe8c42
+:67baa08a3894
 #include "InstCombine.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/IR/DataLayout.h"
-#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/IR/GetElementPtrTypeIterator.h"
-#include "llvm/Support/PatternMatch.h"
+#include "llvm/IR/PatternMatch.h"
 using namespace llvm;
 using namespace PatternMatch;
+#define DEBUG_TYPE "instcombine"
 namespace {
 /// Class representing coefficient of floating-point addend.
 /// This class needs to be highly efficient, which is especially true for
 /// constructor is merely 4-byte-store-zero (Assuming compiler is able to
 /// perform write-merging).
 ///
 class FAddendCoef {
 public:
-// The constructor has to initialize a APFloat, which is uncessary for
+// The constructor has to initialize a APFloat, which is unnecessary for
 // most addends which have coefficient either 1 or -1. So, the constructor
 // is expensive. In order to avoid the cost of the constructor, we should
 // reuse some instances whenever possible. The pre-created instances
 // FAddCombine::Add[0-5] embodies this idea.
 //
 /// represented as <C, V>, where the V is a symbolic value, and C is a
 /// constant coefficient. A constant addend is represented as <C, 0>.
 ///
 class FAddend {
 public:
-FAddend() { Val = 0; }
+FAddend() { Val = nullptr; }
 Value *getSymVal (void) const { return Val; }
 const FAddendCoef &getCoef(void) const { return Coeff; }
-bool isConstant() const { return Val == 0; }
+bool isConstant() const { return Val == nullptr; }
 bool isZero() const { return Coeff.isZero(); }
 void set(short Coefficient, Value *V) { Coeff.set(Coefficient), Val = V; }
 void set(const APFloat& Coefficient, Value *V)
 { Coeff.set(Coefficient); Val = V; }
 /// FAddCombine is the class for optimizing an unsafe fadd/fsub along
 /// with its neighboring at most two instructions.
 ///
 class FAddCombine {
 public:
-FAddCombine(InstCombiner::BuilderTy *B) : Builder(B), Instr(0) {}
+FAddCombine(InstCombiner::BuilderTy *B) : Builder(B), Instr(nullptr) {}
 Value *simplify(Instruction *FAdd);
 private:
 typedef SmallVector<const FAddend*, 4> AddendVect;
 Value *createFAdd(Value *Opnd0, Value *Opnd1);
 Value *createFMul(Value *Opnd0, Value *Opnd1);
 Value *createFDiv(Value *Opnd0, Value *Opnd1);
 Value *createFNeg(Value *V);
 Value *createNaryFAdd(const AddendVect& Opnds, unsigned InstrQuota);
-void createInstPostProc(Instruction *NewInst);
+void createInstPostProc(Instruction *NewInst, bool NoNumber = false);
 InstCombiner::BuilderTy *Builder;
 Instruction *Instr;
 private:
 //
 // Legend: A and B are not constant, C is constant
 //
 unsigned FAddend::drillValueDownOneStep
 (Value *Val, FAddend &Addend0, FAddend &Addend1) {
-Instruction *I = 0;
+Instruction *I = nullptr;
-if (Val == 0 || !(I = dyn_cast<Instruction>(Val)))
+if (!Val || !(I = dyn_cast<Instruction>(Val)))
 return 0;
 unsigned Opcode = I->getOpcode();
 if (Opcode == Instruction::FAdd || Opcode == Instruction::FSub) {
 ConstantFP *C0, *C1;
 Value *Opnd0 = I->getOperand(0);
 Value *Opnd1 = I->getOperand(1);
 if ((C0 = dyn_cast<ConstantFP>(Opnd0)) && C0->isZero())
-Opnd0 = 0;
+Opnd0 = nullptr;
 if ((C1 = dyn_cast<ConstantFP>(Opnd1)) && C1->isZero())
-Opnd1 = 0;
+Opnd1 = nullptr;
 if (Opnd0) {
 if (!C0)
 Addend0.set(1, Opnd0);
 else
-Addend0.set(C0, 0);
+Addend0.set(C0, nullptr);
 }
 if (Opnd1) {
 FAddend &Addend = Opnd0 ? Addend1 : Addend0;
 if (!C1)
 Addend.set(1, Opnd1);
 else
-Addend.set(C1, 0);
+Addend.set(C1, nullptr);
 if (Opcode == Instruction::FSub)
 Addend.negate();
 }
 if (Opnd0 || Opnd1)
 return Opnd0 && Opnd1 ? 2 : 1;
 // Both operands are zero. Weird!
-Addend0.set(APFloat(C0->getValueAPF().getSemantics()), 0);
+Addend0.set(APFloat(C0->getValueAPF().getSemantics()), nullptr);
 return 1;
 }
 if (I->getOpcode() == Instruction::FMul) {
 Value *V0 = I->getOperand(0);
 Instruction *I0 = dyn_cast<Instruction>(I->getOperand(0));
 Instruction *I1 = dyn_cast<Instruction>(I->getOperand(1));
 if (!I0 || !I1 || I0->getOpcode() != I1->getOpcode())
-return 0;
+return nullptr;
 bool isMpy = false;
 if (I0->getOpcode() == Instruction::FMul)
 isMpy = true;
 else if (I0->getOpcode() != Instruction::FDiv)
-return 0;
+return nullptr;
 Value *Opnd0_0 = I0->getOperand(0);
 Value *Opnd0_1 = I0->getOperand(1);
 Value *Opnd1_0 = I1->getOperand(0);
 Value *Opnd1_1 = I1->getOperand(1);
 //  Input Instr I       Factor   AddSub0  AddSub1
 //  ----------------------------------------------
 // (x*y) +/- (x*z)        x        y         z
 // (y/x) +/- (z/x)        x        y         z
 //
-Value *Factor = 0;
+Value *Factor = nullptr;
-Value *AddSub0 = 0, *AddSub1 = 0;
+Value *AddSub0 = nullptr, *AddSub1 = nullptr;
 if (isMpy) {
 if (Opnd0_0 == Opnd1_0 || Opnd0_0 == Opnd1_1)
 Factor = Opnd0_0;
 else if (Opnd0_1 == Opnd1_0 || Opnd0_1 == Opnd1_1)
 AddSub0 = Opnd0_0;
 AddSub1 = Opnd1_0;
 }
 if (!Factor)
-return 0;
+return nullptr;
+FastMathFlags Flags;
+Flags.setUnsafeAlgebra();
+if (I0) Flags &= I->getFastMathFlags();
+if (I1) Flags &= I->getFastMathFlags();
 // Create expression "NewAddSub = AddSub0 +/- AddsSub1"
 Value *NewAddSub = (I->getOpcode() == Instruction::FAdd) ?
 createFAdd(AddSub0, AddSub1) :
 createFSub(AddSub0, AddSub1);
 if (ConstantFP *CFP = dyn_cast<ConstantFP>(NewAddSub)) {
 const APFloat &F = CFP->getValueAPF();
 if (!F.isNormal())
-return 0;
+return nullptr;
-}
+} else if (Instruction *II = dyn_cast<Instruction>(NewAddSub))
+II->setFastMathFlags(Flags);
-if (isMpy)
-return createFMul(Factor, NewAddSub);
+if (isMpy) {
+Value *RI = createFMul(Factor, NewAddSub);
-return createFDiv(NewAddSub, Factor);
+if (Instruction *II = dyn_cast<Instruction>(RI))
+II->setFastMathFlags(Flags);
+return RI;
+}
+Value *RI = createFDiv(NewAddSub, Factor);
+if (Instruction *II = dyn_cast<Instruction>(RI))
+II->setFastMathFlags(Flags);
+return RI;
 }
 Value *FAddCombine::simplify(Instruction *I) {
 assert(I->hasUnsafeAlgebra() && "Should be in unsafe mode");
 // Currently we are not able to handle vector type.
 if (I->getType()->isVectorTy())
-return 0;
+return nullptr;
 assert((I->getOpcode() == Instruction::FAdd ||
 I->getOpcode() == Instruction::FSub) && "Expect add/sub");
 // Save the instruction before calling other member-functions.
 // The input instruction is : "I=0.0 +/- V". If the "V" were able to be
 // splitted into two addends, say "V = X - Y", the instruction would have
 // been optimized into "I = Y - X" in the previous steps.
 //
 const FAddendCoef &CE = Opnd0.getCoef();
-return CE.isOne() ? Opnd0.getSymVal() : 0;
+return CE.isOne() ? Opnd0.getSymVal() : nullptr;
 }
 // step 4: Try to optimize Opnd0 + Opnd1_0 [+ Opnd1_1]
 if (Opnd1_ExpNum) {
 AddendVect AllOpnds;
 // If the resulting expr has constant-addend, this constant-addend is
 // desirable to reside at the top of the resulting expression tree. Placing
 // constant close to supper-expr(s) will potentially reveal some optimization
 // opportunities in super-expr(s).
 //
-const FAddend *ConstAdd = 0;
+const FAddend *ConstAdd = nullptr;
 // Simplified addends are placed <SimpVect>.
 AddendVect SimpVect;
 // The outer loop works on one symbolic-value at a time. Suppose the input
 SameSymIdx < AddendNum; SameSymIdx++) {
 const FAddend *T = Addends[SameSymIdx];
 if (T && T->getSymVal() == Val) {
 // Set null such that next iteration of the outer loop will not process
 // this addend again.
-Addends[SameSymIdx] = 0;
+Addends[SameSymIdx] = nullptr;
 SimpVect.push_back(T);
 }
 }
 // If multiple addends share same symbolic value, fold them together.
 for (unsigned Idx = StartIdx + 1; Idx < SimpVect.size(); Idx++)
 R += *SimpVect[Idx];
 // Pop all addends being folded and push the resulting folded addend.
 SimpVect.resize(StartIdx);
-if (Val != 0) {
+if (Val) {
 if (!R.isZero()) {
 SimpVect.push_back(&R);
 }
 } else {
 // Don't push constant addend at this time. It will be the last element
 // Step 1: Check if the # of instructions needed exceeds the quota.
 //
 unsigned InstrNeeded = calcInstrNumber(Opnds);
 if (InstrNeeded > InstrQuota)
-return 0;
+return nullptr;
 initCreateInstNum();
 // step 2: Emit the N-ary addition.
 // Note that at most three instructions are involved in Fadd-InstCombine: the
 // The resulting optimized addition should have at least one less instruction
 // than the original addition expression tree. This implies that the resulting
 // N-ary addition has at most two instructions, and we don't need to worry
 // about tree-height when constructing the N-ary addition.
-Value *LastVal = 0;
+Value *LastVal = nullptr;
 bool LastValNeedNeg = false;
 // Iterate the addends, creating fadd/fsub using adjacent two addends.
 for (AddendVect::const_iterator I = Opnds.begin(), E = Opnds.end();
 I != E; I++) {
 return V;
 }
 Value *FAddCombine::createFNeg(Value *V) {
 Value *Zero = cast<Value>(ConstantFP::get(V->getType(), 0.0));
-return createFSub(Zero, V);
+Value *NewV = createFSub(Zero, V);
+if (Instruction *I = dyn_cast<Instruction>(NewV))
+createInstPostProc(I, true); // fneg's don't receive instruction numbers.
+return NewV;
 }
 Value *FAddCombine::createFAdd
 (Value *Opnd0, Value *Opnd1) {
 Value *V = Builder->CreateFAdd(Opnd0, Opnd1);
 if (Instruction *I = dyn_cast<Instruction>(V))
 createInstPostProc(I);
 return V;
 }
-void FAddCombine::createInstPostProc(Instruction *NewInstr) {
+void FAddCombine::createInstPostProc(Instruction *NewInstr,
+bool NoNumber) {
 NewInstr->setDebugLoc(Instr->getDebugLoc());
 // Keep track of the number of instruction created.
-incCreateInstNum();
+if (!NoNumber)
+incCreateInstNum();
 // Propagate fast-math flags
 NewInstr->setFastMathFlags(Instr->getFastMathFlags());
 }
 NeedNeg = false;
 return createFMul(OpndVal, Coeff.getValue(Instr->getType()));
 }
-/// AddOne - Add one to a ConstantInt.
+// If one of the operands only has one non-zero bit, and if the other
-static Constant *AddOne(Constant *C) {
+// operand has a known-zero bit in a more significant place than it (not
-return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1));
+// including the sign bit) the ripple may go up to and fill the zero, but
-}
+// won't change the sign. For example, (X & ~4) + 1.
+static bool checkRippleForAdd(const APInt &Op0KnownZero,
-/// SubOne - Subtract one from a ConstantInt.
+const APInt &Op1KnownZero) {
-static Constant *SubOne(ConstantInt *C) {
+APInt Op1MaybeOne = ~Op1KnownZero;
-return ConstantInt::get(C->getContext(), C->getValue()-1);
+// Make sure that one of the operand has at most one bit set to 1.
-}
+if (Op1MaybeOne.countPopulation() != 1)
+return false;
-// dyn_castFoldableMul - If this value is a multiply that can be folded into
+// Find the most significant known 0 other than the sign bit.
-// other computations (because it has a constant operand), return the
+int BitWidth = Op0KnownZero.getBitWidth();
-// non-constant operand of the multiply, and set CST to point to the multiplier.
+APInt Op0KnownZeroTemp(Op0KnownZero);
-// Otherwise, return null.
+Op0KnownZeroTemp.clearBit(BitWidth - 1);
-//
+int Op0ZeroPosition = BitWidth - Op0KnownZeroTemp.countLeadingZeros() - 1;
-static inline Value *dyn_castFoldableMul(Value *V, ConstantInt *&CST) {
-if (!V->hasOneUse() || !V->getType()->isIntegerTy())
+int Op1OnePosition = BitWidth - Op1MaybeOne.countLeadingZeros() - 1;
-return 0;
+assert(Op1OnePosition >= 0);
-Instruction *I = dyn_cast<Instruction>(V);
+// This also covers the case of no known zero, since in that case
-if (I == 0) return 0;
+// Op0ZeroPosition is -1.
+return Op0ZeroPosition >= Op1OnePosition;
-if (I->getOpcode() == Instruction::Mul)
+}
-if ((CST = dyn_cast<ConstantInt>(I->getOperand(1))))
-return I->getOperand(0);
-if (I->getOpcode() == Instruction::Shl)
-if ((CST = dyn_cast<ConstantInt>(I->getOperand(1)))) {
-// The multiplier is really 1 << CST.
-uint32_t BitWidth = cast<IntegerType>(V->getType())->getBitWidth();
-uint32_t CSTVal = CST->getLimitedValue(BitWidth);
-CST = ConstantInt::get(V->getType()->getContext(),
-APInt::getOneBitSet(BitWidth, CSTVal));
-return I->getOperand(0);
-}
-return 0;
-}
 /// WillNotOverflowSignedAdd - Return true if we can prove that:
 ///    (sext (add LHS, RHS))  === (add (sext LHS), (sext RHS))
 /// This basically requires proving that the add in the original type would not
 /// overflow to change the sign bit or have a carry out.
-bool InstCombiner::WillNotOverflowSignedAdd(Value *LHS, Value *RHS) {
+/// TODO: Handle this for Vectors.
+bool InstCombiner::WillNotOverflowSignedAdd(Value *LHS, Value *RHS,
+Instruction *CxtI) {
 // There are different heuristics we can use for this.  Here are some simple
 // ones.
-// Add has the property that adding any two 2's complement numbers can only
+// If LHS and RHS each have at least two sign bits, the addition will look
-// have one carry bit which can change a sign.  As such, if LHS and RHS each
+// like
-// have at least two sign bits, we know that the addition of the two values
+//
-// will sign extend fine.
+// XX..... +
-if (ComputeNumSignBits(LHS) > 1 && ComputeNumSignBits(RHS) > 1)
+// 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, 0, CxtI) > 1 &&
+ComputeNumSignBits(RHS, 0, CxtI) > 1)
 return true;
+if (IntegerType *IT = dyn_cast<IntegerType>(LHS->getType())) {
-// If one of the operands only has one non-zero bit, and if the other operand
+int BitWidth = IT->getBitWidth();
-// has a known-zero bit in a more significant place than it (not including the
+APInt LHSKnownZero(BitWidth, 0);
-// sign bit) the ripple may go up to and fill the zero, but won't change the
+APInt LHSKnownOne(BitWidth, 0);
-// sign.  For example, (X & ~4) + 1.
+computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, CxtI);
-// TODO: Implement.
+APInt RHSKnownZero(BitWidth, 0);
+APInt RHSKnownOne(BitWidth, 0);
+computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, CxtI);
+// Addition of two 2's compliment numbers having opposite signs will never
+// overflow.
+if ((LHSKnownOne[BitWidth - 1] && RHSKnownZero[BitWidth - 1]) ||
+(LHSKnownZero[BitWidth - 1] && RHSKnownOne[BitWidth - 1]))
+return true;
+// Check if carry bit of addition will not cause overflow.
+if (checkRippleForAdd(LHSKnownZero, RHSKnownZero))
+return true;
+if (checkRippleForAdd(RHSKnownZero, LHSKnownZero))
+return true;
+}
 return false;
 }
+/// WillNotOverflowUnsignedAdd - Return true if we can prove that:
+///    (zext (add LHS, RHS))  === (add (zext LHS), (zext RHS))
+bool InstCombiner::WillNotOverflowUnsignedAdd(Value *LHS, Value *RHS,
+Instruction *CxtI) {
+// There are different heuristics we can use for this. Here is a simple one.
+// If the sign bit of LHS and that of RHS are both zero, no unsigned wrap.
+bool LHSKnownNonNegative, LHSKnownNegative;
+bool RHSKnownNonNegative, RHSKnownNegative;
+ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, DL, 0, AT, CxtI, DT);
+ComputeSignBit(RHS, RHSKnownNonNegative, RHSKnownNegative, DL, 0, AT, CxtI, DT);
+if (LHSKnownNonNegative && RHSKnownNonNegative)
+return true;
+return false;
+}
+/// \brief Return true if we can prove that:
+///    (sub LHS, RHS)  === (sub nsw LHS, RHS)
+/// This basically requires proving that the add in the original type would not
+/// overflow to change the sign bit or have a carry out.
+/// TODO: Handle this for Vectors.
+bool InstCombiner::WillNotOverflowSignedSub(Value *LHS, Value *RHS,
+Instruction *CxtI) {
+// If LHS and RHS each have at least two sign bits, the subtraction
+// cannot overflow.
+if (ComputeNumSignBits(LHS, 0, CxtI) > 1 &&
+ComputeNumSignBits(RHS, 0, CxtI) > 1)
+return true;
+if (IntegerType *IT = dyn_cast<IntegerType>(LHS->getType())) {
+unsigned BitWidth = IT->getBitWidth();
+APInt LHSKnownZero(BitWidth, 0);
+APInt LHSKnownOne(BitWidth, 0);
+computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, CxtI);
+APInt RHSKnownZero(BitWidth, 0);
+APInt RHSKnownOne(BitWidth, 0);
+computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, CxtI);
+// Subtraction of two 2's compliment numbers having identical signs will
+// never overflow.
+if ((LHSKnownOne[BitWidth - 1] && RHSKnownOne[BitWidth - 1]) ||
+(LHSKnownZero[BitWidth - 1] && RHSKnownZero[BitWidth - 1]))
+return true;
+// TODO: implement logic similar to checkRippleForAdd
+}
+return false;
+}
+/// \brief Return true if we can prove that:
+///    (sub LHS, RHS)  === (sub nuw LHS, RHS)
+bool InstCombiner::WillNotOverflowUnsignedSub(Value *LHS, Value *RHS,
+Instruction *CxtI) {
+// If the LHS is negative and the RHS is non-negative, no unsigned wrap.
+bool LHSKnownNonNegative, LHSKnownNegative;
+bool RHSKnownNonNegative, RHSKnownNegative;
+ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, DL, 0, AT, CxtI, DT);
+ComputeSignBit(RHS, RHSKnownNonNegative, RHSKnownNegative, DL, 0, AT, CxtI, DT);
+if (LHSKnownNegative && RHSKnownNonNegative)
+return true;
+return false;
+}
+// Checks if any operand is negative and we can convert add to sub.
+// This function checks for following negative patterns
+//   ADD(XOR(OR(Z, NOT(C)), C)), 1) == NEG(AND(Z, C))
+//   ADD(XOR(AND(Z, C), C), 1) == NEG(OR(Z, ~C))
+//   XOR(AND(Z, C), (C + 1)) == NEG(OR(Z, ~C)) if C is even
+static Value *checkForNegativeOperand(BinaryOperator &I,
+InstCombiner::BuilderTy *Builder) {
+Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
+// This function creates 2 instructions to replace ADD, we need at least one
+// of LHS or RHS to have one use to ensure benefit in transform.
+if (!LHS->hasOneUse() && !RHS->hasOneUse())
+return nullptr;
+Value *X = nullptr, *Y = nullptr, *Z = nullptr;
+const APInt *C1 = nullptr, *C2 = nullptr;
+// if ONE is on other side, swap
+if (match(RHS, m_Add(m_Value(X), m_One())))
+std::swap(LHS, RHS);
+if (match(LHS, m_Add(m_Value(X), m_One()))) {
+// if XOR on other side, swap
+if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
+std::swap(X, RHS);
+if (match(X, m_Xor(m_Value(Y), m_APInt(C1)))) {
+// X = XOR(Y, C1), Y = OR(Z, C2), C2 = NOT(C1) ==> X == NOT(AND(Z, C1))
+// ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, AND(Z, C1))
+if (match(Y, m_Or(m_Value(Z), m_APInt(C2))) && (*C2 == ~(*C1))) {
+Value *NewAnd = Builder->CreateAnd(Z, *C1);
+return Builder->CreateSub(RHS, NewAnd, "sub");
+} else if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && (*C1 == *C2)) {
+// X = XOR(Y, C1), Y = AND(Z, C2), C2 == C1 ==> X == NOT(OR(Z, ~C1))
+// ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, OR(Z, ~C1))
+Value *NewOr = Builder->CreateOr(Z, ~(*C1));
+return Builder->CreateSub(RHS, NewOr, "sub");
+}
+}
+}
+// Restore LHS and RHS
+LHS = I.getOperand(0);
+RHS = I.getOperand(1);
+// if XOR is on other side, swap
+if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
+std::swap(LHS, RHS);
+// C2 is ODD
+// LHS = XOR(Y, C1), Y = AND(Z, C2), C1 == (C2 + 1) => LHS == NEG(OR(Z, ~C2))
+// ADD(LHS, RHS) == SUB(RHS, OR(Z, ~C2))
+if (match(LHS, m_Xor(m_Value(Y), m_APInt(C1))))
+if (C1->countTrailingZeros() == 0)
+if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && *C1 == (*C2 + 1)) {
+Value *NewOr = Builder->CreateOr(Z, ~(*C2));
+return Builder->CreateSub(RHS, NewOr, "sub");
+}
+return nullptr;
+}
 Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
 bool Changed = SimplifyAssociativeOrCommutative(I);
 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
-if (Value *V = SimplifyAddInst(LHS, RHS, I.hasNoSignedWrap(),
+if (Value *V = SimplifyVectorOp(I))
-I.hasNoUnsignedWrap(), TD))
+return ReplaceInstUsesWith(I, V);
-return ReplaceInstUsesWith(I, V);
+if (Value *V = SimplifyAddInst(LHS, RHS, I.hasNoSignedWrap(),
-// (A*B)+(A*C) -> A*(B+C) etc
+I.hasNoUnsignedWrap(), DL, TLI, DT, AT))
+return ReplaceInstUsesWith(I, V);
+// (A*B)+(A*C) -> A*(B+C) etc
 if (Value *V = SimplifyUsingDistributiveLaws(I))
 return ReplaceInstUsesWith(I, V);
 if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
 // X + (signbit) --> X ^ signbit
 // zext(bool) + C -> bool ? C + 1 : C
 if (ZExtInst *ZI = dyn_cast<ZExtInst>(LHS))
 if (ZI->getSrcTy()->isIntegerTy(1))
 return SelectInst::Create(ZI->getOperand(0), AddOne(CI), CI);
-Value *XorLHS = 0; ConstantInt *XorRHS = 0;
+Value *XorLHS = nullptr; ConstantInt *XorRHS = nullptr;
 if (match(LHS, m_Xor(m_Value(XorLHS), m_ConstantInt(XorRHS)))) {
 uint32_t TySizeBits = I.getType()->getScalarSizeInBits();
 const APInt &RHSVal = CI->getValue();
 unsigned ExtendAmt = 0;
 // If we have ADD(XOR(AND(X, 0xFF), 0x80), 0xF..F80), it's a sext.
 ExtendAmt = TySizeBits - XorRHS->getValue().logBase2() - 1;
 }
 if (ExtendAmt) {
 APInt Mask = APInt::getHighBitsSet(TySizeBits, ExtendAmt);
-if (!MaskedValueIsZero(XorLHS, Mask))
+if (!MaskedValueIsZero(XorLHS, Mask, 0, &I))
 ExtendAmt = 0;
 }
 if (ExtendAmt) {
 Constant *ShAmt = ConstantInt::get(I.getType(), ExtendAmt);
 // a sub and fuse this add with it.
 if (LHS->hasOneUse() && (XorRHS->getValue()+1).isPowerOf2()) {
 IntegerType *IT = cast<IntegerType>(I.getType());
 APInt LHSKnownOne(IT->getBitWidth(), 0);
 APInt LHSKnownZero(IT->getBitWidth(), 0);
-ComputeMaskedBits(XorLHS, LHSKnownZero, LHSKnownOne);
+computeKnownBits(XorLHS, LHSKnownZero, LHSKnownOne, 0, &I);
 if ((XorRHS->getValue() | LHSKnownZero).isAllOnesValue())
 return BinaryOperator::CreateSub(ConstantExpr::getAdd(XorRHS, CI),
 XorLHS);
 }
 // (X + signbit) + C could have gotten canonicalized to (X ^ signbit) + C,
 if (isa<Constant>(RHS) && isa<PHINode>(LHS))
 if (Instruction *NV = FoldOpIntoPhi(I))
 return NV;
-if (I.getType()->isIntegerTy(1))
+if (I.getType()->getScalarType()->isIntegerTy(1))
 return BinaryOperator::CreateXor(LHS, RHS);
 // X + X --> X << 1
 if (LHS == RHS) {
 BinaryOperator *New =
 // A + -B  -->  A - B
 if (!isa<Constant>(RHS))
 if (Value *V = dyn_castNegVal(RHS))
 return BinaryOperator::CreateSub(LHS, V);
+if (Value *V = checkForNegativeOperand(I, Builder))
-ConstantInt *C2;
+return ReplaceInstUsesWith(I, V);
-if (Value *X = dyn_castFoldableMul(LHS, C2)) {
-if (X == RHS)   // X*C + X --> X * (C+1)
-return BinaryOperator::CreateMul(RHS, AddOne(C2));
-// X*C1 + X*C2 --> X * (C1+C2)
-ConstantInt *C1;
-if (X == dyn_castFoldableMul(RHS, C1))
-return BinaryOperator::CreateMul(X, ConstantExpr::getAdd(C1, C2));
-}
-// X + X*C --> X * (C+1)
-if (dyn_castFoldableMul(RHS, C2) == LHS)
-return BinaryOperator::CreateMul(LHS, AddOne(C2));
 // A+B --> A|B iff A and B have no bits set in common.
 if (IntegerType *IT = dyn_cast<IntegerType>(I.getType())) {
 APInt LHSKnownOne(IT->getBitWidth(), 0);
 APInt LHSKnownZero(IT->getBitWidth(), 0);
-ComputeMaskedBits(LHS, LHSKnownZero, LHSKnownOne);
+computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, &I);
 if (LHSKnownZero != 0) {
 APInt RHSKnownOne(IT->getBitWidth(), 0);
 APInt RHSKnownZero(IT->getBitWidth(), 0);
-ComputeMaskedBits(RHS, RHSKnownZero, RHSKnownOne);
+computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, &I);
 // No bits in common -> bitwise or.
 if ((LHSKnownZero|RHSKnownZero).isAllOnesValue())
 return BinaryOperator::CreateOr(LHS, RHS);
 }
 }
-// W*X + Y*Z --> W * (X+Z)  iff W == Y
+if (Constant *CRHS = dyn_cast<Constant>(RHS)) {
-{
+Value *X;
-Value *W, *X, *Y, *Z;
+if (match(LHS, m_Not(m_Value(X)))) // ~X + C --> (C-1) - X
-if (match(LHS, m_Mul(m_Value(W), m_Value(X))) &&
+return BinaryOperator::CreateSub(SubOne(CRHS), X);
-match(RHS, m_Mul(m_Value(Y), m_Value(Z)))) {
-if (W != Y) {
-if (W == Z) {
-std::swap(Y, Z);
-} else if (Y == X) {
-std::swap(W, X);
-} else if (X == Z) {
-std::swap(Y, Z);
-std::swap(W, X);
-}
-}
-if (W == Y) {
-Value *NewAdd = Builder->CreateAdd(X, Z, LHS->getName());
-return BinaryOperator::CreateMul(W, NewAdd);
-}
-}
 }
 if (ConstantInt *CRHS = dyn_cast<ConstantInt>(RHS)) {
-Value *X = 0;
-if (match(LHS, m_Not(m_Value(X))))    // ~X + C --> (C-1) - X
-return BinaryOperator::CreateSub(SubOne(CRHS), X);
 // (X & FF00) + xx00  -> (X+xx00) & FF00
+Value *X;
+ConstantInt *C2;
 if (LHS->hasOneUse() &&
 match(LHS, m_And(m_Value(X), m_ConstantInt(C2))) &&
 CRHS->getValue() == (CRHS->getValue() & C2->getValue())) {
 // See if all bits from the first bit set in the Add RHS up are included
 // in the mask.  First, get the rightmost bit.
 if (ConstantInt *RHSC = dyn_cast<ConstantInt>(RHS)) {
 Constant *CI =
 ConstantExpr::getTrunc(RHSC, LHSConv->getOperand(0)->getType());
 if (LHSConv->hasOneUse() &&
 ConstantExpr::getSExt(CI, I.getType()) == RHSC &&
-WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI)) {
+WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, &I)) {
 // Insert the new, smaller add.
 Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
 CI, "addconv");
 return new SExtInst(NewAdd, I.getType());
 }
 // single use (so we don't increase the number of sexts), and if the
 // integer add will not overflow.
 if (LHSConv->getOperand(0)->getType()==RHSConv->getOperand(0)->getType()&&
 (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
 WillNotOverflowSignedAdd(LHSConv->getOperand(0),
-RHSConv->getOperand(0))) {
+RHSConv->getOperand(0), &I)) {
 // Insert the new integer add.
 Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
 RHSConv->getOperand(0), "addconv");
 return new SExtInst(NewAdd, I.getType());
 }
 }
 }
-// Check for (x & y) + (x ^ y)
+// (add (xor A, B) (and A, B)) --> (or A, B)
 {
-Value *A = 0, *B = 0;
+Value *A = nullptr, *B = nullptr;
 if (match(RHS, m_Xor(m_Value(A), m_Value(B))) &&
 (match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
 match(LHS, m_And(m_Specific(B), m_Specific(A)))))
 return BinaryOperator::CreateOr(A, B);
 (match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
 match(RHS, m_And(m_Specific(B), m_Specific(A)))))
 return BinaryOperator::CreateOr(A, B);
 }
-return Changed ? &I : 0;
+// (add (or A, B) (and A, B)) --> (add A, B)
+{
+Value *A = nullptr, *B = nullptr;
+if (match(RHS, m_Or(m_Value(A), m_Value(B))) &&
+(match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
+match(LHS, m_And(m_Specific(B), m_Specific(A))))) {
+auto *New = BinaryOperator::CreateAdd(A, B);
+New->setHasNoSignedWrap(I.hasNoSignedWrap());
+New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
+return New;
+}
+if (match(LHS, m_Or(m_Value(A), m_Value(B))) &&
+(match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
+match(RHS, m_And(m_Specific(B), m_Specific(A))))) {
+auto *New = BinaryOperator::CreateAdd(A, B);
+New->setHasNoSignedWrap(I.hasNoSignedWrap());
+New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
+return New;
+}
+}
+// TODO(jingyue): Consider WillNotOverflowSignedAdd and
+// WillNotOverflowUnsignedAdd to reduce the number of invocations of
+// computeKnownBits.
+if (!I.hasNoSignedWrap() && WillNotOverflowSignedAdd(LHS, RHS, &I)) {
+Changed = true;
+I.setHasNoSignedWrap(true);
+}
+if (!I.hasNoUnsignedWrap() && WillNotOverflowUnsignedAdd(LHS, RHS, &I)) {
+Changed = true;
+I.setHasNoUnsignedWrap(true);
+}
+return Changed ? &I : nullptr;
 }
 Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
 bool Changed = SimplifyAssociativeOrCommutative(I);
 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
-if (Value *V = SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), TD))
+if (Value *V = SimplifyVectorOp(I))
+return ReplaceInstUsesWith(I, V);
+if (Value *V = SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), DL,
+TLI, DT, AT))
 return ReplaceInstUsesWith(I, V);
 if (isa<Constant>(RHS)) {
 if (isa<PHINode>(LHS))
 if (Instruction *NV = FoldOpIntoPhi(I))
 return NV;
 }
 // -A + B  -->  B - A
 // -A + -B  -->  -(A + B)
-if (Value *LHSV = dyn_castFNegVal(LHS))
+if (Value *LHSV = dyn_castFNegVal(LHS)) {
-return BinaryOperator::CreateFSub(RHS, LHSV);
+Instruction *RI = BinaryOperator::CreateFSub(RHS, LHSV);
+RI->copyFastMathFlags(&I);
+return RI;
+}
 // A + -B  -->  A - B
 if (!isa<Constant>(RHS))
-if (Value *V = dyn_castFNegVal(RHS))
+if (Value *V = dyn_castFNegVal(RHS)) {
-return BinaryOperator::CreateFSub(LHS, V);
+Instruction *RI = BinaryOperator::CreateFSub(LHS, V);
+RI->copyFastMathFlags(&I);
+return RI;
+}
 // Check for (fadd double (sitofp x), y), see if we can merge this into an
 // integer add followed by a promotion.
 if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
 // (fadd double (sitofp x), fpcst) --> (sitofp (add int x, intcst))
 if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS)) {
 Constant *CI =
 ConstantExpr::getFPToSI(CFP, LHSConv->getOperand(0)->getType());
 if (LHSConv->hasOneUse() &&
 ConstantExpr::getSIToFP(CI, I.getType()) == CFP &&
-WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI)) {
+WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, &I)) {
 // Insert the new integer add.
 Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
 CI, "addconv");
 return new SIToFPInst(NewAdd, I.getType());
 }
 // single use (so we don't increase the number of int->fp conversions),
 // and if the integer add will not overflow.
 if (LHSConv->getOperand(0)->getType()==RHSConv->getOperand(0)->getType()&&
 (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
 WillNotOverflowSignedAdd(LHSConv->getOperand(0),
-RHSConv->getOperand(0))) {
+RHSConv->getOperand(0), &I)) {
 // Insert the new integer add.
 Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
 RHSConv->getOperand(0),"addconv");
 return new SIToFPInst(NewAdd, I.getType());
 }
 {
 Value *A1, *B1, *C1, *A2, *B2, *C2;
 if (match(LHS, m_Select(m_Value(C1), m_Value(A1), m_Value(B1))) &&
 match(RHS, m_Select(m_Value(C2), m_Value(A2), m_Value(B2)))) {
 if (C1 == C2) {
-Constant *Z1=0, *Z2=0;
+Constant *Z1=nullptr, *Z2=nullptr;
 Value *A, *B, *C=C1;
 if (match(A1, m_AnyZero()) && match(B2, m_AnyZero())) {
 Z1 = dyn_cast<Constant>(A1); A = A2;
 Z2 = dyn_cast<Constant>(B2); B = B1;
 } else if (match(B1, m_AnyZero()) && match(A2, m_AnyZero())) {
 if (I.hasUnsafeAlgebra()) {
 if (Value *V = FAddCombine(Builder).simplify(&I))
 return ReplaceInstUsesWith(I, V);
 }
-return Changed ? &I : 0;
+return Changed ? &I : nullptr;
 }
 /// Optimize pointer differences into the same array into a size.  Consider:
 ///  &A[10] - &A[0]: we should compile this to "10".  LHS/RHS are the pointer
 /// operands to the ptrtoint instructions for the LHS/RHS of the subtract.
 ///
 Value *InstCombiner::OptimizePointerDifference(Value *LHS, Value *RHS,
 Type *Ty) {
-assert(TD && "Must have target data info for this");
+assert(DL && "Must have target data info for this");
 // If LHS is a gep based on RHS or RHS is a gep based on LHS, we can optimize
 // this.
 bool Swapped = false;
-GEPOperator *GEP1 = 0, *GEP2 = 0;
+GEPOperator *GEP1 = nullptr, *GEP2 = nullptr;
 // For now we require one side to be the base pointer "A" or a constant
 // GEP derived from it.
 if (GEPOperator *LHSGEP = dyn_cast<GEPOperator>(LHS)) {
 // (gep X, ...) - X
 }
 }
 // Avoid duplicating the arithmetic if GEP2 has non-constant indices and
 // multiple users.
-if (GEP1 == 0 ||
+if (!GEP1 ||
-(GEP2 != 0 && !GEP2->hasAllConstantIndices() && !GEP2->hasOneUse()))
+(GEP2 && !GEP2->hasAllConstantIndices() && !GEP2->hasOneUse()))
-return 0;
+return nullptr;
 // Emit the offset of the GEP and an intptr_t.
 Value *Result = EmitGEPOffset(GEP1);
 // If we had a constant expression GEP on the other side offsetting the
 Instruction *InstCombiner::visitSub(BinaryOperator &I) {
 Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
+if (Value *V = SimplifyVectorOp(I))
+return ReplaceInstUsesWith(I, V);
 if (Value *V = SimplifySubInst(Op0, Op1, I.hasNoSignedWrap(),
-I.hasNoUnsignedWrap(), TD))
+I.hasNoUnsignedWrap(), DL, TLI, DT, AT))
 return ReplaceInstUsesWith(I, V);
 // (A*B)-(A*C) -> A*(B-C) etc
 if (Value *V = SimplifyUsingDistributiveLaws(I))
 return ReplaceInstUsesWith(I, V);
-// If this is a 'B = x-(-A)', change to B = x+A.  This preserves NSW/NUW.
+// If this is a 'B = x-(-A)', change to B = x+A.
 if (Value *V = dyn_castNegVal(Op1)) {
 BinaryOperator *Res = BinaryOperator::CreateAdd(Op0, V);
-Res->setHasNoSignedWrap(I.hasNoSignedWrap());
-Res->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
+if (const auto *BO = dyn_cast<BinaryOperator>(Op1)) {
+assert(BO->getOpcode() == Instruction::Sub &&
+"Expected a subtraction operator!");
+if (BO->hasNoSignedWrap() && I.hasNoSignedWrap())
+Res->setHasNoSignedWrap(true);
+} else {
+if (cast<Constant>(Op1)->isNotMinSignedValue() && I.hasNoSignedWrap())
+Res->setHasNoSignedWrap(true);
+}
 return Res;
 }
 if (I.getType()->isIntegerTy(1))
 return BinaryOperator::CreateXor(Op0, Op1);
 // Replace (-1 - A) with (~A).
 if (match(Op0, m_AllOnes()))
 return BinaryOperator::CreateNot(Op1);
-if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
+if (Constant *C = dyn_cast<Constant>(Op0)) {
 // C - ~X == X + (1+C)
-Value *X = 0;
+Value *X = nullptr;
 if (match(Op1, m_Not(m_Value(X))))
 return BinaryOperator::CreateAdd(X, AddOne(C));
+// Try to fold constant sub into select arguments.
+if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
+if (Instruction *R = FoldOpIntoSelect(I, SI))
+return R;
+// C-(X+C2) --> (C-C2)-X
+Constant *C2;
+if (match(Op1, m_Add(m_Value(X), m_Constant(C2))))
+return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
+if (SimplifyDemandedInstructionBits(I))
+return &I;
+// Fold (sub 0, (zext bool to B)) --> (sext bool to B)
+if (C->isNullValue() && match(Op1, m_ZExt(m_Value(X))))
+if (X->getType()->getScalarType()->isIntegerTy(1))
+return CastInst::CreateSExtOrBitCast(X, Op1->getType());
+// Fold (sub 0, (sext bool to B)) --> (zext bool to B)
+if (C->isNullValue() && match(Op1, m_SExt(m_Value(X))))
+if (X->getType()->getScalarType()->isIntegerTy(1))
+return CastInst::CreateZExtOrBitCast(X, Op1->getType());
+}
+if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
 // -(X >>u 31) -> (X >>s 31)
 // -(X >>s 31) -> (X >>u 31)
 if (C->isZero()) {
 Value *X; ConstantInt *CI;
 if (match(Op1, m_LShr(m_Value(X), m_ConstantInt(CI))) &&
 if (match(Op1, m_AShr(m_Value(X), m_ConstantInt(CI))) &&
 // Verify we are shifting out everything but the sign bit.
 CI->getValue() == I.getType()->getPrimitiveSizeInBits()-1)
 return BinaryOperator::CreateLShr(X, CI);
 }
-// Try to fold constant sub into select arguments.
-if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
-if (Instruction *R = FoldOpIntoSelect(I, SI))
-return R;
-// C-(X+C2) --> (C-C2)-X
-ConstantInt *C2;
-if (match(Op1, m_Add(m_Value(X), m_ConstantInt(C2))))
-return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
-if (SimplifyDemandedInstructionBits(I))
-return &I;
-// Fold (sub 0, (zext bool to B)) --> (sext bool to B)
-if (C->isZero() && match(Op1, m_ZExt(m_Value(X))))
-if (X->getType()->isIntegerTy(1))
-return CastInst::CreateSExtOrBitCast(X, Op1->getType());
-// Fold (sub 0, (sext bool to B)) --> (zext bool to B)
-if (C->isZero() && match(Op1, m_SExt(m_Value(X))))
-if (X->getType()->isIntegerTy(1))
-return CastInst::CreateZExtOrBitCast(X, Op1->getType());
 }
 { Value *Y;
 // X-(X+Y) == -Y    X-(Y+X) == -Y
 if (match(Op0, m_Sub(m_Specific(Op1), m_Value(Y))))
 return BinaryOperator::CreateNeg(Y);
 }
 if (Op1->hasOneUse()) {
-Value *X = 0, *Y = 0, *Z = 0;
+Value *X = nullptr, *Y = nullptr, *Z = nullptr;
-Constant *C = 0;
+Constant *C = nullptr;
-ConstantInt *CI = 0;
+Constant *CI = nullptr;
 // (X - (Y - Z))  -->  (X + (Z - Y)).
 if (match(Op1, m_Sub(m_Value(Y), m_Value(Z))))
 return BinaryOperator::CreateAdd(Op0,
 Builder->CreateSub(Z, Y, Op1->getName()));
 if (match(Op1, m_And(m_Value(Y), m_Specific(Op0))) ||
 match(Op1, m_And(m_Specific(Op0), m_Value(Y))))
 return BinaryOperator::CreateAnd(Op0,
 Builder->CreateNot(Y, Y->getName() + ".not"));
-// 0 - (X sdiv C)  -> (X sdiv -C)
+// 0 - (X sdiv C)  -> (X sdiv -C)  provided the negation doesn't overflow.
-if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) &&
+if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) && match(Op0, m_Zero()) &&
-match(Op0, m_Zero()))
+C->isNotMinSignedValue() && !C->isOneValue())
 return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C));
 // 0 - (X << Y)  -> (-X << Y)   when X is freely negatable.
 if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero()))
 if (Value *XNeg = dyn_castNegVal(X))
 return BinaryOperator::CreateShl(XNeg, Y);
-// X - X*C --> X * (1-C)
-if (match(Op1, m_Mul(m_Specific(Op0), m_ConstantInt(CI)))) {
-Constant *CP1 = ConstantExpr::getSub(ConstantInt::get(I.getType(),1), CI);
-return BinaryOperator::CreateMul(Op0, CP1);
-}
-// X - X<<C --> X * (1-(1<<C))
-if (match(Op1, m_Shl(m_Specific(Op0), m_ConstantInt(CI)))) {
-Constant *One = ConstantInt::get(I.getType(), 1);
-C = ConstantExpr::getSub(One, ConstantExpr::getShl(One, CI));
-return BinaryOperator::CreateMul(Op0, C);
-}
 // X - A*-B -> X + A*B
 // X - -A*B -> X + A*B
 Value *A, *B;
 if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
 match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B))))
 return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B));
 // X - A*CI -> X + A*-CI
 // X - CI*A -> X + A*-CI
-if (match(Op1, m_Mul(m_Value(A), m_ConstantInt(CI))) ||
+if (match(Op1, m_Mul(m_Value(A), m_Constant(CI))) ||
-match(Op1, m_Mul(m_ConstantInt(CI), m_Value(A)))) {
+match(Op1, m_Mul(m_Constant(CI), m_Value(A)))) {
 Value *NewMul = Builder->CreateMul(A, ConstantExpr::getNeg(CI));
 return BinaryOperator::CreateAdd(Op0, NewMul);
 }
 }
-ConstantInt *C1;
-if (Value *X = dyn_castFoldableMul(Op0, C1)) {
-if (X == Op1)  // X*C - X --> X * (C-1)
-return BinaryOperator::CreateMul(Op1, SubOne(C1));
-ConstantInt *C2;   // X*C1 - X*C2 -> X * (C1-C2)
-if (X == dyn_castFoldableMul(Op1, C2))
-return BinaryOperator::CreateMul(X, ConstantExpr::getSub(C1, C2));
-}
 // Optimize pointer differences into the same array into a size.  Consider:
 //  &A[10] - &A[0]: we should compile this to "10".
-if (TD) {
+if (DL) {
 Value *LHSOp, *RHSOp;
 if (match(Op0, m_PtrToInt(m_Value(LHSOp))) &&
 match(Op1, m_PtrToInt(m_Value(RHSOp))))
 if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType()))
 return ReplaceInstUsesWith(I, Res);
 // trunc(p)-trunc(q) -> trunc(p-q)
 if (match(Op0, m_Trunc(m_PtrToInt(m_Value(LHSOp)))) &&
 match(Op1, m_Trunc(m_PtrToInt(m_Value(RHSOp)))))
 if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType()))
 return ReplaceInstUsesWith(I, Res);
 }
-return 0;
+bool Changed = false;
+if (!I.hasNoSignedWrap() && WillNotOverflowSignedSub(Op0, Op1, &I)) {
+Changed = true;
+I.setHasNoSignedWrap(true);
+}
+if (!I.hasNoUnsignedWrap() && WillNotOverflowUnsignedSub(Op0, Op1, &I)) {
+Changed = true;
+I.setHasNoUnsignedWrap(true);
+}
+return Changed ? &I : nullptr;
 }
 Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
 Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
-if (Value *V = SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), TD))
+if (Value *V = SimplifyVectorOp(I))
+return ReplaceInstUsesWith(I, V);
+if (Value *V = SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), DL,
+TLI, DT, AT))
 return ReplaceInstUsesWith(I, V);
 if (isa<Constant>(Op0))
 if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
 if (Instruction *NV = FoldOpIntoSelect(I, SI))
 if (I.hasUnsafeAlgebra()) {
 if (Value *V = FAddCombine(Builder).simplify(&I))
 return ReplaceInstUsesWith(I, V);
 }
-return 0;
+return nullptr;
 }

Mercurial > hg > Members > tobaru > cbc > CbC_llvm

comparison lib/Transforms/InstCombine/InstCombineAddSub.cpp @ 80:67baa08a3894