diff options
author | Eli Bendersky <eliben@chromium.org> | 2013-07-15 16:09:15 -0700 |
---|---|---|
committer | Eli Bendersky <eliben@chromium.org> | 2013-07-15 16:09:15 -0700 |
commit | c6cf05cb5108f356dde97c01ee4188b0671d4542 (patch) | |
tree | 436fdc2a55296d3c202e7ef11f31be3be53efb5f /lib/Transforms/InstCombine | |
parent | c75199c649c739aade160289d93f257edc798cde (diff) | |
parent | 7dfcb84fc16b3bf6b2379713b53090757f0a45f9 (diff) |
Merge commit '7dfcb84fc16b3bf6b2379713b53090757f0a45f9'
Conflicts:
docs/LangRef.rst
include/llvm/CodeGen/CallingConvLower.h
include/llvm/IRReader/IRReader.h
include/llvm/Target/TargetMachine.h
lib/CodeGen/CallingConvLower.cpp
lib/IRReader/IRReader.cpp
lib/IRReader/LLVMBuild.txt
lib/IRReader/Makefile
lib/LLVMBuild.txt
lib/Makefile
lib/Support/MemoryBuffer.cpp
lib/Support/Unix/PathV2.inc
lib/Target/ARM/ARMBaseInstrInfo.cpp
lib/Target/ARM/ARMISelLowering.cpp
lib/Target/ARM/ARMInstrInfo.td
lib/Target/ARM/ARMSubtarget.cpp
lib/Target/ARM/ARMTargetMachine.cpp
lib/Target/Mips/CMakeLists.txt
lib/Target/Mips/MipsDelaySlotFiller.cpp
lib/Target/Mips/MipsISelLowering.cpp
lib/Target/Mips/MipsInstrInfo.td
lib/Target/Mips/MipsSubtarget.cpp
lib/Target/Mips/MipsSubtarget.h
lib/Target/X86/X86FastISel.cpp
lib/Target/X86/X86ISelDAGToDAG.cpp
lib/Target/X86/X86ISelLowering.cpp
lib/Target/X86/X86InstrControl.td
lib/Target/X86/X86InstrFormats.td
lib/Transforms/IPO/ExtractGV.cpp
lib/Transforms/InstCombine/InstCombineCompares.cpp
lib/Transforms/Utils/SimplifyLibCalls.cpp
test/CodeGen/X86/fast-isel-divrem.ll
test/MC/ARM/data-in-code.ll
tools/Makefile
tools/llvm-extract/llvm-extract.cpp
tools/llvm-link/CMakeLists.txt
tools/opt/CMakeLists.txt
tools/opt/LLVMBuild.txt
tools/opt/Makefile
tools/opt/opt.cpp
Diffstat (limited to 'lib/Transforms/InstCombine')
-rw-r--r-- | lib/Transforms/InstCombine/CMakeLists.txt | 2 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombine.h | 1 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineAddSub.cpp | 279 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 28 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineCalls.cpp | 3 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineCasts.cpp | 16 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineCompares.cpp | 176 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp | 82 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineMulDivRem.cpp | 145 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombinePHI.cpp | 192 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineSelect.cpp | 103 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineVectorOps.cpp | 85 | ||||
-rw-r--r-- | lib/Transforms/InstCombine/InstructionCombining.cpp | 2 |
13 files changed, 790 insertions, 324 deletions
diff --git a/lib/Transforms/InstCombine/CMakeLists.txt b/lib/Transforms/InstCombine/CMakeLists.txt index 72cfe2c985..a25696ec03 100644 --- a/lib/Transforms/InstCombine/CMakeLists.txt +++ b/lib/Transforms/InstCombine/CMakeLists.txt @@ -9,7 +9,7 @@ add_llvm_library(LLVMInstCombine InstCombineMulDivRem.cpp InstCombinePHI.cpp InstCombineSelect.cpp - InstCombineShifts.cpp + InstCombineShifts.cpp InstCombineSimplifyDemanded.cpp InstCombineVectorOps.cpp ) diff --git a/lib/Transforms/InstCombine/InstCombine.h b/lib/Transforms/InstCombine/InstCombine.h index 1f6a3a5e33..2a36074750 100644 --- a/lib/Transforms/InstCombine/InstCombine.h +++ b/lib/Transforms/InstCombine/InstCombine.h @@ -233,6 +233,7 @@ private: Instruction *transformSExtICmp(ICmpInst *ICI, Instruction &CI); bool WillNotOverflowSignedAdd(Value *LHS, Value *RHS); Value *EmitGEPOffset(User *GEP); + Instruction *scalarizePHI(ExtractElementInst &EI, PHINode *PN); public: // InsertNewInstBefore - insert an instruction New before instruction Old diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp index c6d60d6f00..166f8dfdb4 100644 --- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -24,9 +24,9 @@ namespace { /// Class representing coefficient of floating-point addend. /// This class needs to be highly efficient, which is especially true for /// the constructor. As of I write this comment, the cost of the default - /// constructor is merely 4-byte-store-zero (Assuming compiler is able to + /// 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 @@ -37,31 +37,31 @@ namespace { // FAddendCoef() : IsFp(false), BufHasFpVal(false), IntVal(0) {} ~FAddendCoef(); - + void set(short C) { assert(!insaneIntVal(C) && "Insane coefficient"); IsFp = false; IntVal = C; } - + void set(const APFloat& C); - + void negate(); - + bool isZero() const { return isInt() ? !IntVal : getFpVal().isZero(); } Value *getValue(Type *) const; - + // If possible, don't define operator+/operator- etc because these // operators inevitably call FAddendCoef's constructor which is not cheap. void operator=(const FAddendCoef &A); void operator+=(const FAddendCoef &A); void operator-=(const FAddendCoef &A); void operator*=(const FAddendCoef &S); - + bool isOne() const { return isInt() && IntVal == 1; } bool isTwo() const { return isInt() && IntVal == 2; } bool isMinusOne() const { return isInt() && IntVal == -1; } bool isMinusTwo() const { return isInt() && IntVal == -2; } - + private: bool insaneIntVal(int V) { return V > 4 || V < -4; } APFloat *getFpValPtr(void) @@ -74,18 +74,28 @@ namespace { return *getFpValPtr(); } - APFloat &getFpVal(void) - { assert(IsFp && BufHasFpVal && "Incorret state"); return *getFpValPtr(); } - + APFloat &getFpVal(void) { + assert(IsFp && BufHasFpVal && "Incorret state"); + return *getFpValPtr(); + } + bool isInt() const { return !IsFp; } + // If the coefficient is represented by an integer, promote it to a + // floating point. + void convertToFpType(const fltSemantics &Sem); + + // Construct an APFloat from a signed integer. + // TODO: We should get rid of this function when APFloat can be constructed + // from an *SIGNED* integer. + APFloat createAPFloatFromInt(const fltSemantics &Sem, int Val); private: bool IsFp; - + // True iff FpValBuf contains an instance of APFloat. bool BufHasFpVal; - + // The integer coefficient of an individual addend is either 1 or -1, // and we try to simplify at most 4 addends from neighboring at most // two instructions. So the range of <IntVal> falls in [-4, 4]. APInt @@ -94,7 +104,7 @@ namespace { AlignedCharArrayUnion<APFloat> FpValBuf; }; - + /// FAddend is used to represent floating-point addend. An addend is /// 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>. @@ -102,10 +112,10 @@ namespace { class FAddend { public: FAddend() { Val = 0; } - + Value *getSymVal (void) const { return Val; } const FAddendCoef &getCoef(void) const { return Coeff; } - + bool isConstant() const { return Val == 0; } bool isZero() const { return Coeff.isZero(); } @@ -114,17 +124,17 @@ namespace { { Coeff.set(Coefficient); Val = V; } void set(const ConstantFP* Coefficient, Value *V) { Coeff.set(Coefficient->getValueAPF()); Val = V; } - + void negate() { Coeff.negate(); } - + /// Drill down the U-D chain one step to find the definition of V, and /// try to break the definition into one or two addends. static unsigned drillValueDownOneStep(Value* V, FAddend &A0, FAddend &A1); - + /// Similar to FAddend::drillDownOneStep() except that the value being /// splitted is the addend itself. unsigned drillAddendDownOneStep(FAddend &Addend0, FAddend &Addend1) const; - + void operator+=(const FAddend &T) { assert((Val == T.Val) && "Symbolic-values disagree"); Coeff += T.Coeff; @@ -132,12 +142,12 @@ namespace { private: void Scale(const FAddendCoef& ScaleAmt) { Coeff *= ScaleAmt; } - + // This addend has the value of "Coeff * Val". Value *Val; FAddendCoef Coeff; }; - + /// FAddCombine is the class for optimizing an unsafe fadd/fsub along /// with its neighboring at most two instructions. /// @@ -145,27 +155,30 @@ namespace { public: FAddCombine(InstCombiner::BuilderTy *B) : Builder(B), Instr(0) {} Value *simplify(Instruction *FAdd); - + private: typedef SmallVector<const FAddend*, 4> AddendVect; - + Value *simplifyFAdd(AddendVect& V, unsigned InstrQuota); - + + Value *performFactorization(Instruction *I); + /// Convert given addend to a Value Value *createAddendVal(const FAddend &A, bool& NeedNeg); - + /// Return the number of instructions needed to emit the N-ary addition. unsigned calcInstrNumber(const AddendVect& Vect); Value *createFSub(Value *Opnd0, Value *Opnd1); 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); - + InstCombiner::BuilderTy *Builder; Instruction *Instr; - + private: // Debugging stuff are clustered here. #ifndef NDEBUG @@ -177,7 +190,7 @@ namespace { void incCreateInstNum() {} #endif }; -} +} //===----------------------------------------------------------------------===// // @@ -200,10 +213,34 @@ void FAddendCoef::set(const APFloat& C) { } else *P = C; - IsFp = BufHasFpVal = true; + IsFp = BufHasFpVal = true; +} + +void FAddendCoef::convertToFpType(const fltSemantics &Sem) { + if (!isInt()) + return; + + APFloat *P = getFpValPtr(); + if (IntVal > 0) + new(P) APFloat(Sem, IntVal); + else { + new(P) APFloat(Sem, 0 - IntVal); + P->changeSign(); + } + IsFp = BufHasFpVal = true; } -void FAddendCoef::operator=(const FAddendCoef& That) { +APFloat FAddendCoef::createAPFloatFromInt(const fltSemantics &Sem, int Val) { + if (Val >= 0) + return APFloat(Sem, Val); + + APFloat T(Sem, 0 - Val); + T.changeSign(); + + return T; +} + +void FAddendCoef::operator=(const FAddendCoef &That) { if (That.isInt()) set(That.IntVal); else @@ -219,16 +256,16 @@ void FAddendCoef::operator+=(const FAddendCoef &That) { getFpVal().add(That.getFpVal(), RndMode); return; } - + if (isInt()) { const APFloat &T = That.getFpVal(); - set(T); - getFpVal().add(APFloat(T.getSemantics(), IntVal), RndMode); + convertToFpType(T.getSemantics()); + getFpVal().add(T, RndMode); return; } - + APFloat &T = getFpVal(); - T.add(APFloat(T.getSemantics(), That.IntVal), RndMode); + T.add(createAPFloatFromInt(T.getSemantics(), That.IntVal), RndMode); } void FAddendCoef::operator-=(const FAddendCoef &That) { @@ -240,16 +277,16 @@ void FAddendCoef::operator-=(const FAddendCoef &That) { getFpVal().subtract(That.getFpVal(), RndMode); return; } - + if (isInt()) { const APFloat &T = That.getFpVal(); - set(T); - getFpVal().subtract(APFloat(T.getSemantics(), IntVal), RndMode); + convertToFpType(T.getSemantics()); + getFpVal().subtract(T, RndMode); return; } APFloat &T = getFpVal(); - T.subtract(APFloat(T.getSemantics(), IntVal), RndMode); + T.subtract(createAPFloatFromInt(T.getSemantics(), IntVal), RndMode); } void FAddendCoef::operator*=(const FAddendCoef &That) { @@ -268,15 +305,16 @@ void FAddendCoef::operator*=(const FAddendCoef &That) { return; } - const fltSemantics &Semantic = + const fltSemantics &Semantic = isInt() ? That.getFpVal().getSemantics() : getFpVal().getSemantics(); if (isInt()) - set(APFloat(Semantic, IntVal)); + convertToFpType(Semantic); APFloat &F0 = getFpVal(); if (That.isInt()) - F0.multiply(APFloat(Semantic, That.IntVal), APFloat::rmNearestTiesToEven); + F0.multiply(createAPFloatFromInt(Semantic, That.IntVal), + APFloat::rmNearestTiesToEven); else F0.multiply(That.getFpVal(), APFloat::rmNearestTiesToEven); @@ -302,11 +340,11 @@ Value *FAddendCoef::getValue(Type *Ty) const { // A - B <1, A>, <1,B> // 0 - B <-1, B> // C * A, <C, A> -// A + C <1, A> <C, NULL> +// A + C <1, A> <C, NULL> // 0 +/- 0 <0, NULL> (corner case) // // Legend: A and B are not constant, C is constant -// +// unsigned FAddend::drillValueDownOneStep (Value *Val, FAddend &Addend0, FAddend &Addend1) { Instruction *I = 0; @@ -377,7 +415,7 @@ unsigned FAddend::drillAddendDownOneStep return 0; unsigned BreakNum = FAddend::drillValueDownOneStep(Val, Addend0, Addend1); - if (!BreakNum || Coeff.isOne()) + if (!BreakNum || Coeff.isOne()) return BreakNum; Addend0.Scale(Coeff); @@ -388,6 +426,78 @@ unsigned FAddend::drillAddendDownOneStep return BreakNum; } +// Try to perform following optimization on the input instruction I. Return the +// simplified expression if was successful; otherwise, return 0. +// +// Instruction "I" is Simplified into +// ------------------------------------------------------- +// (x * y) +/- (x * z) x * (y +/- z) +// (y / x) +/- (z / x) (y +/- z) / x +// +Value *FAddCombine::performFactorization(Instruction *I) { + assert((I->getOpcode() == Instruction::FAdd || + I->getOpcode() == Instruction::FSub) && "Expect add/sub"); + + 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; + + bool isMpy = false; + if (I0->getOpcode() == Instruction::FMul) + isMpy = true; + else if (I0->getOpcode() != Instruction::FDiv) + return 0; + + 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 *AddSub0 = 0, *AddSub1 = 0; + + if (isMpy) { + if (Opnd0_0 == Opnd1_0 || Opnd0_0 == Opnd1_1) + Factor = Opnd0_0; + else if (Opnd0_1 == Opnd1_0 || Opnd0_1 == Opnd1_1) + Factor = Opnd0_1; + + if (Factor) { + AddSub0 = (Factor == Opnd0_0) ? Opnd0_1 : Opnd0_0; + AddSub1 = (Factor == Opnd1_0) ? Opnd1_1 : Opnd1_0; + } + } else if (Opnd0_1 == Opnd1_1) { + Factor = Opnd0_1; + AddSub0 = Opnd0_0; + AddSub1 = Opnd1_0; + } + + if (!Factor) + return 0; + + // 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() || F.isDenormal()) + return 0; + } + + if (isMpy) + return createFMul(Factor, NewAddSub); + + return createFDiv(NewAddSub, Factor); +} + Value *FAddCombine::simplify(Instruction *I) { assert(I->hasUnsafeAlgebra() && "Should be in unsafe mode"); @@ -398,7 +508,7 @@ Value *FAddCombine::simplify(Instruction *I) { assert((I->getOpcode() == Instruction::FAdd || I->getOpcode() == Instruction::FSub) && "Expect add/sub"); - // Save the instruction before calling other member-functions. + // Save the instruction before calling other member-functions. Instr = I; FAddend Opnd0, Opnd1, Opnd0_0, Opnd0_1, Opnd1_0, Opnd1_1; @@ -409,7 +519,7 @@ Value *FAddCombine::simplify(Instruction *I) { unsigned Opnd0_ExpNum = 0; unsigned Opnd1_ExpNum = 0; - if (!Opnd0.isConstant()) + if (!Opnd0.isConstant()) Opnd0_ExpNum = Opnd0.drillAddendDownOneStep(Opnd0_0, Opnd0_1); // Step 2: Expand the 2nd addend into Opnd1_0 and Opnd1_1. @@ -431,7 +541,7 @@ Value *FAddCombine::simplify(Instruction *I) { Value *V0 = I->getOperand(0); Value *V1 = I->getOperand(1); - InstQuota = ((!isa<Constant>(V0) && V0->hasOneUse()) && + InstQuota = ((!isa<Constant>(V0) && V0->hasOneUse()) && (!isa<Constant>(V1) && V1->hasOneUse())) ? 2 : 1; if (Value *R = simplifyFAdd(AllOpnds, InstQuota)) @@ -471,7 +581,8 @@ Value *FAddCombine::simplify(Instruction *I) { return R; } - return 0; + // step 6: Try factorization as the last resort, + return performFactorization(I); } Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { @@ -479,7 +590,7 @@ Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { unsigned AddendNum = Addends.size(); assert(AddendNum <= 4 && "Too many addends"); - // For saving intermediate results; + // For saving intermediate results; unsigned NextTmpIdx = 0; FAddend TmpResult[3]; @@ -495,7 +606,7 @@ Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { AddendVect SimpVect; // The outer loop works on one symbolic-value at a time. Suppose the input - // addends are : <a1, x>, <b1, y>, <a2, x>, <c1, z>, <b2, y>, ... + // addends are : <a1, x>, <b1, y>, <a2, x>, <c1, z>, <b2, y>, ... // The symbolic-values will be processed in this order: x, y, z. // for (unsigned SymIdx = 0; SymIdx < AddendNum; SymIdx++) { @@ -522,7 +633,7 @@ Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { 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] = 0; SimpVect.push_back(T); } } @@ -535,7 +646,7 @@ Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { R += *SimpVect[Idx]; // Pop all addends being folded and push the resulting folded addend. - SimpVect.resize(StartIdx); + SimpVect.resize(StartIdx); if (Val != 0) { if (!R.isZero()) { SimpVect.push_back(&R); @@ -548,7 +659,7 @@ Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) { } } - assert((NextTmpIdx <= sizeof(TmpResult)/sizeof(TmpResult[0]) + 1) && + assert((NextTmpIdx <= sizeof(TmpResult)/sizeof(TmpResult[0]) + 1) && "out-of-bound access"); if (ConstAdd) @@ -570,7 +681,7 @@ Value *FAddCombine::createNaryFAdd assert(!Opnds.empty() && "Expect at least one addend"); // Step 1: Check if the # of instructions needed exceeds the quota. - // + // unsigned InstrNeeded = calcInstrNumber(Opnds); if (InstrNeeded > InstrQuota) return 0; @@ -591,7 +702,7 @@ Value *FAddCombine::createNaryFAdd // Iterate the addends, creating fadd/fsub using adjacent two addends. for (AddendVect::const_iterator I = Opnds.begin(), E = Opnds.end(); I != E; I++) { - bool NeedNeg; + bool NeedNeg; Value *V = createAddendVal(**I, NeedNeg); if (!LastVal) { LastVal = V; @@ -617,7 +728,7 @@ Value *FAddCombine::createNaryFAdd } #ifndef NDEBUG - assert(CreateInstrNum == InstrNeeded && + assert(CreateInstrNum == InstrNeeded && "Inconsistent in instruction numbers"); #endif @@ -627,7 +738,8 @@ Value *FAddCombine::createNaryFAdd Value *FAddCombine::createFSub (Value *Opnd0, Value *Opnd1) { Value *V = Builder->CreateFSub(Opnd0, Opnd1); - createInstPostProc(cast<Instruction>(V)); + if (Instruction *I = dyn_cast<Instruction>(V)) + createInstPostProc(I); return V; } @@ -639,13 +751,22 @@ Value *FAddCombine::createFNeg(Value *V) { Value *FAddCombine::createFAdd (Value *Opnd0, Value *Opnd1) { Value *V = Builder->CreateFAdd(Opnd0, Opnd1); - createInstPostProc(cast<Instruction>(V)); + if (Instruction *I = dyn_cast<Instruction>(V)) + createInstPostProc(I); return V; } Value *FAddCombine::createFMul(Value *Opnd0, Value *Opnd1) { Value *V = Builder->CreateFMul(Opnd0, Opnd1); - createInstPostProc(cast<Instruction>(V)); + if (Instruction *I = dyn_cast<Instruction>(V)) + createInstPostProc(I); + return V; +} + +Value *FAddCombine::createFDiv(Value *Opnd0, Value *Opnd1) { + Value *V = Builder->CreateFDiv(Opnd0, Opnd1); + if (Instruction *I = dyn_cast<Instruction>(V)) + createInstPostProc(I); return V; } @@ -665,8 +786,8 @@ unsigned FAddCombine::calcInstrNumber(const AddendVect &Opnds) { unsigned OpndNum = Opnds.size(); unsigned InstrNeeded = OpndNum - 1; - // The number of addends in the form of "(-1)*x". - unsigned NegOpndNum = 0; + // The number of addends in the form of "(-1)*x". + unsigned NegOpndNum = 0; // Adjust the number of instructions needed to emit the N-ary add. for (AddendVect::const_iterator I = Opnds.begin(), E = Opnds.end(); @@ -853,6 +974,11 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) { return BinaryOperator::CreateSub(ConstantExpr::getAdd(XorRHS, CI), XorLHS); } + // (X + signbit) + C could have gotten canonicalized to (X ^ signbit) + C, + // transform them into (X + (signbit ^ C)) + if (XorRHS->getValue().isSignBit()) + return BinaryOperator::CreateAdd(XorLHS, + ConstantExpr::getXor(XorRHS, CI)); } } @@ -1111,6 +1237,31 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) { } } + // select C, 0, B + select C, A, 0 -> select C, A, B + { + 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; + 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())) { + Z1 = dyn_cast<Constant>(B1); B = B2; + Z2 = dyn_cast<Constant>(A2); A = A1; + } + + if (Z1 && Z2 && + (I.hasNoSignedZeros() || + (Z1->isNegativeZeroValue() && Z2->isNegativeZeroValue()))) { + return SelectInst::Create(C, A, B); + } + } + } + } + if (I.hasUnsafeAlgebra()) { if (Value *V = FAddCombine(Builder).simplify(&I)) return ReplaceInstUsesWith(I, V); diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 4332467371..ec75dd2e04 100644 --- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -22,8 +22,8 @@ using namespace PatternMatch; /// AddOne - Add one to a ConstantInt. -static Constant *AddOne(Constant *C) { - return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1)); +static Constant *AddOne(ConstantInt *C) { + return ConstantInt::get(C->getContext(), C->getValue() + 1); } /// SubOne - Subtract one from a ConstantInt. static Constant *SubOne(ConstantInt *C) { @@ -266,9 +266,8 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, return 0; } - -/// InsertRangeTest - Emit a computation of: (V >= Lo && V < Hi) if Inside is -/// true, otherwise (V < Lo || V >= Hi). In practice, we emit the more efficient +/// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise +/// (V < Lo || V >= Hi). In practice, we emit the more efficient /// (V-Lo) \<u Hi-Lo. This method expects that Lo <= Hi. isSigned indicates /// whether to treat the V, Lo and HI as signed or not. IB is the location to /// insert new instructions. @@ -935,6 +934,9 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { if (LHS->getPredicate() == FCmpInst::FCMP_ORD && RHS->getPredicate() == FCmpInst::FCMP_ORD) { + if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType()) + return 0; + // (fcmp ord x, c) & (fcmp ord y, c) -> (fcmp ord x, y) if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1))) if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) { @@ -1545,14 +1547,6 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) { switch (RHSCC) { default: llvm_unreachable("Unknown integer condition code!"); case ICmpInst::ICMP_EQ: - if (LHSCst == SubOne(RHSCst)) { - // (X == 13 | X == 14) -> X-13 <u 2 - Constant *AddCST = ConstantExpr::getNeg(LHSCst); - Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off"); - AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst); - return Builder->CreateICmpULT(Add, AddCST); - } - if (LHS->getOperand(0) == RHS->getOperand(0)) { // if LHSCst and RHSCst differ only by one bit: // (A == C1 || A == C2) -> (A & ~(C1 ^ C2)) == C1 @@ -1566,6 +1560,14 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) { } } + if (LHSCst == SubOne(RHSCst)) { + // (X == 13 | X == 14) -> X-13 <u 2 + Constant *AddCST = ConstantExpr::getNeg(LHSCst); + Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off"); + AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst); + return Builder->CreateICmpULT(Add, AddCST); + } + break; // (X == 13 | X == 15) -> no change case ICmpInst::ICMP_UGT: // (X == 13 | X u> 14) -> no change case ICmpInst::ICMP_SGT: // (X == 13 | X s> 14) -> no change diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp index 64cd1bd278..78b4a2c6c9 100644 --- a/lib/Transforms/InstCombine/InstCombineCalls.cpp +++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp @@ -1372,7 +1372,8 @@ InstCombiner::transformCallThroughTrampoline(CallSite CS, NestF->getType() == PointerType::getUnqual(NewFTy) ? NestF : ConstantExpr::getBitCast(NestF, PointerType::getUnqual(NewFTy)); - const AttributeSet &NewPAL = AttributeSet::get(FTy->getContext(), NewAttrs); + const AttributeSet &NewPAL = + AttributeSet::get(FTy->getContext(), NewAttrs); Instruction *NewCaller; if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) { diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index a960ab2499..2ee1278d23 100644 --- a/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -104,6 +104,12 @@ Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI, uint64_t CastElTySize = TD->getTypeAllocSize(CastElTy); if (CastElTySize == 0 || AllocElTySize == 0) return 0; + // If the allocation has multiple uses, only promote it if we're not + // shrinking the amount of memory being allocated. + uint64_t AllocElTyStoreSize = TD->getTypeStoreSize(AllocElTy); + uint64_t CastElTyStoreSize = TD->getTypeStoreSize(CastElTy); + if (!AI.hasOneUse() && CastElTyStoreSize < AllocElTyStoreSize) return 0; + // See if we can satisfy the modulus by pulling a scale out of the array // size argument. unsigned ArraySizeScale; @@ -1604,6 +1610,9 @@ static Value *OptimizeIntegerToVectorInsertions(BitCastInst &CI, /// OptimizeIntToFloatBitCast - See if we can optimize an integer->float/double /// bitcast. The various long double bitcasts can't get in here. static Instruction *OptimizeIntToFloatBitCast(BitCastInst &CI,InstCombiner &IC){ + // We need to know the target byte order to perform this optimization. + if (!IC.getDataLayout()) return 0; + Value *Src = CI.getOperand(0); Type *DestTy = CI.getType(); @@ -1625,7 +1634,10 @@ static Instruction *OptimizeIntToFloatBitCast(BitCastInst &CI,InstCombiner &IC){ VecInput = IC.Builder->CreateBitCast(VecInput, VecTy); } - return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(0)); + unsigned Elt = 0; + if (IC.getDataLayout()->isBigEndian()) + Elt = VecTy->getPrimitiveSizeInBits() / DestWidth - 1; + return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(Elt)); } } @@ -1647,6 +1659,8 @@ static Instruction *OptimizeIntToFloatBitCast(BitCastInst &CI,InstCombiner &IC){ } unsigned Elt = ShAmt->getZExtValue() / DestWidth; + if (IC.getDataLayout()->isBigEndian()) + Elt = VecTy->getPrimitiveSizeInBits() / DestWidth - 1 - Elt; return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(Elt)); } } diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp index 6eca399a40..518a8323b6 100644 --- a/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -139,6 +139,31 @@ static bool isSignBitCheck(ICmpInst::Predicate pred, ConstantInt *RHS, } } +/// Returns true if the exploded icmp can be expressed as a signed comparison +/// to zero and updates the predicate accordingly. +/// The signedness of the comparison is preserved. +static bool isSignTest(ICmpInst::Predicate &pred, const ConstantInt *RHS) { + if (!ICmpInst::isSigned(pred)) + return false; + + if (RHS->isZero()) + return ICmpInst::isRelational(pred); + + if (RHS->isOne()) { + if (pred == ICmpInst::ICMP_SLT) { + pred = ICmpInst::ICMP_SLE; + return true; + } + } else if (RHS->isAllOnesValue()) { + if (pred == ICmpInst::ICMP_SGT) { + pred = ICmpInst::ICMP_SGE; + return true; + } + } + + return false; +} + // isHighOnes - Return true if the constant is of the form 1+0+. // This is the same as lowones(~X). static bool isHighOnes(const ConstantInt *CI) { @@ -443,20 +468,29 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV, } - // If a 32-bit or 64-bit magic bitvector captures the entire comparison state + // If a magic bitvector captures the entire comparison state // of this load, replace it with computation that does: // ((magic_cst >> i) & 1) != 0 - if (ArrayElementCount <= 32 || - (TD && ArrayElementCount <= 64 && TD->isLegalInteger(64))) { - Type *Ty; - if (ArrayElementCount <= 32) + { + Type *Ty = 0; + + // Look for an appropriate type: + // - The type of Idx if the magic fits + // - The smallest fitting legal type if we have a DataLayout + // - Default to i32 + if (ArrayElementCount <= Idx->getType()->getIntegerBitWidth()) + Ty = Idx->getType(); + else if (TD) + Ty = TD->getSmallestLegalIntType(Init->getContext(), ArrayElementCount); + else if (ArrayElementCount <= 32) Ty = Type::getInt32Ty(Init->getContext()); - else - Ty = Type::getInt64Ty(Init->getContext()); - Value *V = Builder->CreateIntCast(Idx, Ty, false); - V = Builder->CreateLShr(ConstantInt::get(Ty, MagicBitvector), V); - V = Builder->CreateAnd(ConstantInt::get(Ty, 1), V); - return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0)); + + if (Ty != 0) { + Value *V = Builder->CreateIntCast(Idx, Ty, false); + V = Builder->CreateLShr(ConstantInt::get(Ty, MagicBitvector), V); + V = Builder->CreateAnd(ConstantInt::get(Ty, 1), V); + return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0)); + } } return 0; @@ -1273,6 +1307,23 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, break; } + case Instruction::Mul: { // (icmp pred (mul X, Val), CI) + ConstantInt *Val = dyn_cast<ConstantInt>(LHSI->getOperand(1)); + if (!Val) break; + + // If this is a signed comparison to 0 and the mul is sign preserving, + // use the mul LHS operand instead. + ICmpInst::Predicate pred = ICI.getPredicate(); + if (isSignTest(pred, RHS) && !Val->isZero() && + cast<BinaryOperator>(LHSI)->hasNoSignedWrap()) + return new ICmpInst(Val->isNegative() ? + ICmpInst::getSwappedPredicate(pred) : pred, + LHSI->getOperand(0), + Constant::getNullValue(RHS->getType())); + + break; + } + case Instruction::Shl: { // (icmp pred (shl X, ShAmt), CI) ConstantInt *ShAmt = dyn_cast<ConstantInt>(LHSI->getOperand(1)); if (!ShAmt) break; @@ -1304,6 +1355,12 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0), ConstantExpr::getLShr(RHS, ShAmt)); + // If the shift is NSW and we compare to 0, then it is just shifting out + // sign bits, no need for an AND either. + if (cast<BinaryOperator>(LHSI)->hasNoSignedWrap() && RHSV == 0) + return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0), + ConstantExpr::getLShr(RHS, ShAmt)); + if (LHSI->hasOneUse()) { // Otherwise strength reduce the shift into an and. uint32_t ShAmtVal = (uint32_t)ShAmt->getLimitedValue(TypeBits); @@ -1318,6 +1375,15 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, } } + // If this is a signed comparison to 0 and the shift is sign preserving, + // use the shift LHS operand instead. + ICmpInst::Predicate pred = ICI.getPredicate(); + if (isSignTest(pred, RHS) && + cast<BinaryOperator>(LHSI)->hasNoSignedWrap()) + return new ICmpInst(pred, + LHSI->getOperand(0), + Constant::getNullValue(RHS->getType())); + // Otherwise, if this is a comparison of the sign bit, simplify to and/test. bool TrueIfSigned = false; if (LHSI->hasOneUse() && @@ -1333,18 +1399,19 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, } // Transform (icmp pred iM (shl iM %v, N), CI) - // -> (icmp pred i(M-N) (trunc %v iM to i(N-N)), (trunc (CI>>N)) - // Transform the shl to a trunc if (trunc (CI>>N)) has no loss. + // -> (icmp pred i(M-N) (trunc %v iM to i(M-N)), (trunc (CI>>N)) + // Transform the shl to a trunc if (trunc (CI>>N)) has no loss and M-N. // This enables to get rid of the shift in favor of a trunc which can be // free on the target. It has the additional benefit of comparing to a // smaller constant, which will be target friendly. unsigned Amt = ShAmt->getLimitedValue(TypeBits-1); - // @LOCALMOD-BEGIN - // We don't want to introduce non-power-of-two integer sizes for PNaCl's - // stable wire format, so modify this transformation for NaCl. - if (Amt != 0 && RHSV.countTrailingZeros() >= Amt && - isPowerOf2_32(TypeBits - Amt) && (TypeBits - Amt) >= 8) { - // @LOCALMOD-END + if (LHSI->hasOneUse() && + // @LOCALMOD-BEGIN + // We don't want to introduce non-power-of-two integer sizes for PNaCl's + // stable wire format, so modify this transformation for NaCl. + isPowerOf2_32(TypeBits - Amt) && (TypeBits - Amt) >= 8 && + // @LOCALMOD-END + Amt != 0 && RHSV.countTrailingZeros() >= Amt) { Type *NTy = IntegerType::get(ICI.getContext(), TypeBits - Amt); Constant *NCI = ConstantExpr::getTrunc( ConstantExpr::getAShr(RHS, @@ -1536,6 +1603,19 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, return new ICmpInst(pred, X, NegX); } } + break; + case Instruction::Mul: + if (RHSV == 0 && BO->hasNoSignedWrap()) { + if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) { + // The trivial case (mul X, 0) is handled by InstSimplify + // General case : (mul X, C) != 0 iff X != 0 + // (mul X, C) == 0 iff X == 0 + if (!BOC->isZero()) + return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), + Constant::getNullValue(RHS->getType())); + } + } + break; default: break; } } else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(LHSI)) { @@ -2416,6 +2496,55 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) { return new ICmpInst(Pred, Y, Z); } + // icmp slt (X + -1), Y -> icmp sle X, Y + if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLT && + match(B, m_AllOnes())) + return new ICmpInst(CmpInst::ICMP_SLE, A, Op1); + + // icmp sge (X + -1), Y -> icmp sgt X, Y + if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGE && + match(B, m_AllOnes())) + return new ICmpInst(CmpInst::ICMP_SGT, A, Op1); + + // icmp sle (X + 1), Y -> icmp slt X, Y + if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLE && + match(B, m_One())) + return new ICmpInst(CmpInst::ICMP_SLT, A, Op1); + + // icmp sgt (X + 1), Y -> icmp sge X, Y + if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGT && + match(B, m_One())) + return new ICmpInst(CmpInst::ICMP_SGE, A, Op1); + + // if C1 has greater magnitude than C2: + // icmp (X + C1), (Y + C2) -> icmp (X + C3), Y + // s.t. C3 = C1 - C2 + // + // if C2 has greater magnitude than C1: + // icmp (X + C1), (Y + C2) -> icmp X, (Y + C3) + // s.t. C3 = C2 - C1 + if (A && C && NoOp0WrapProblem && NoOp1WrapProblem && + (BO0->hasOneUse() || BO1->hasOneUse()) && !I.isUnsigned()) + if (ConstantInt *C1 = dyn_cast<ConstantInt>(B)) + if (ConstantInt *C2 = dyn_cast<ConstantInt>(D)) { + const APInt &AP1 = C1->getValue(); + const APInt &AP2 = C2->getValue(); + if (AP1.isNegative() == AP2.isNegative()) { + APInt AP1Abs = C1->getValue().abs(); + APInt AP2Abs = C2->getValue().abs(); + if (AP1Abs.uge(AP2Abs)) { + ConstantInt *C3 = Builder->getInt(AP1 - AP2); + Value *NewAdd = Builder->CreateNSWAdd(A, C3); + return new ICmpInst(Pred, NewAdd, C); + } else { + ConstantInt *C3 = Builder->getInt(AP2 - AP1); + Value *NewAdd = Builder->CreateNSWAdd(C, C3); + return new ICmpInst(Pred, A, NewAdd); + } + } + } + + // Analyze the case when either Op0 or Op1 is a sub instruction. // Op0 = A - B (or A and B are null); Op1 = C - D (or C and D are null). A = 0; B = 0; C = 0; D = 0; @@ -2549,6 +2678,15 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) { } { Value *A, *B; + // Transform (A & ~B) == 0 --> (A & B) != 0 + // and (A & ~B) != 0 --> (A & B) == 0 + // if A is a power of 2. + if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) && + match(Op1, m_Zero()) && isKnownToBeAPowerOfTwo(A) && I.isEquality()) + return new ICmpInst(I.getInversePredicate(), + Builder->CreateAnd(A, B), + Op1); + // ~x < ~y --> y < x // ~x < cst --> ~cst < x if (match(Op0, m_Not(m_Value(A)))) { diff --git a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp index 337cfe32a8..e2d7966cb3 100644 --- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp +++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp @@ -69,8 +69,8 @@ isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy, if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) { // If the GEP has all zero indices, it doesn't offset the pointer. If it // doesn't, it does. - if (!isOnlyCopiedFromConstantGlobal(GEP, TheCopy, ToDelete, - IsOffset || !GEP->hasAllZeroIndices())) + if (!isOnlyCopiedFromConstantGlobal( + GEP, TheCopy, ToDelete, IsOffset || !GEP->hasAllZeroIndices())) return false; continue; } @@ -166,7 +166,7 @@ Instruction *InstCombiner::visitAllocaInst(AllocaInst &AI) { // Convert: alloca Ty, C - where C is a constant != 1 into: alloca [C x Ty], 1 if (AI.isArrayAllocation()) { // Check C != 1 if (const ConstantInt *C = dyn_cast<ConstantInt>(AI.getArraySize())) { - Type *NewTy = + Type *NewTy = ArrayType::get(AI.getAllocatedType(), C->getZExtValue()); AllocaInst *New = Builder->CreateAlloca(NewTy, 0, AI.getName()); New->setAlignment(AI.getAlignment()); @@ -294,7 +294,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, Type *SrcPTy = SrcTy->getElementType(); - if (DestPTy->isIntegerTy() || DestPTy->isPointerTy() || + if (DestPTy->isIntegerTy() || DestPTy->isPointerTy() || DestPTy->isVectorTy()) { // If the source is an array, the code below will not succeed. Check to // see if a trivial 'gep P, 0, 0' will help matters. Only do this for @@ -311,7 +311,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, } if (IC.getDataLayout() && - (SrcPTy->isIntegerTy() || SrcPTy->isPointerTy() || + (SrcPTy->isIntegerTy() || SrcPTy->isPointerTy() || SrcPTy->isVectorTy()) && // Do not allow turning this into a load of an integer, which is then // casted to a pointer, this pessimizes pointer analysis a lot. @@ -322,7 +322,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, // Okay, we are casting from one integer or pointer type to another of // the same size. Instead of casting the pointer before the load, cast // the result of the loaded value. - LoadInst *NewLoad = + LoadInst *NewLoad = IC.Builder->CreateLoad(CastOp, LI.isVolatile(), CI->getName()); NewLoad->setAlignment(LI.getAlignment()); NewLoad->setAtomic(LI.getOrdering(), LI.getSynchScope()); @@ -359,7 +359,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { // None of the following transforms are legal for volatile/atomic loads. // FIXME: Some of it is okay for atomic loads; needs refactoring. if (!LI.isSimple()) return 0; - + // Do really simple store-to-load forwarding and load CSE, to catch cases // where there are several consecutive memory accesses to the same location, // separated by a few arithmetic operations. @@ -380,7 +380,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { Constant::getNullValue(Op->getType()), &LI); return ReplaceInstUsesWith(LI, UndefValue::get(LI.getType())); } - } + } // load null/undef -> unreachable // TODO: Consider a target hook for valid address spaces for this xform. @@ -399,7 +399,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { if (CE->isCast()) if (Instruction *Res = InstCombineLoadCast(*this, LI, TD)) return Res; - + if (Op->hasOneUse()) { // Change select and PHI nodes to select values instead of addresses: this // helps alias analysis out a lot, allows many others simplifications, and @@ -453,18 +453,18 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { Type *DestPTy = cast<PointerType>(CI->getType())->getElementType(); PointerType *SrcTy = dyn_cast<PointerType>(CastOp->getType()); if (SrcTy == 0) return 0; - + Type *SrcPTy = SrcTy->getElementType(); if (!DestPTy->isIntegerTy() && !DestPTy->isPointerTy()) return 0; - + /// NewGEPIndices - If SrcPTy is an aggregate type, we can emit a "noop gep" /// to its first element. This allows us to handle things like: /// store i32 xxx, (bitcast {foo*, float}* %P to i32*) /// on 32-bit hosts. SmallVector<Value*, 4> NewGEPIndices; - + // If the source is an array, the code below will not succeed. Check to // see if a trivial 'gep P, 0, 0' will help matters. Only do this for // constants. @@ -472,7 +472,7 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { // Index through pointer. Constant *Zero = Constant::getNullValue(Type::getInt32Ty(SI.getContext())); NewGEPIndices.push_back(Zero); - + while (1) { if (StructType *STy = dyn_cast<StructType>(SrcPTy)) { if (!STy->getNumElements()) /* Struct can be empty {} */ @@ -486,24 +486,24 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { break; } } - + SrcTy = PointerType::get(SrcPTy, SrcTy->getAddressSpace()); } if (!SrcPTy->isIntegerTy() && !SrcPTy->isPointerTy()) return 0; - + // If the pointers point into different address spaces or if they point to // values with different sizes, we can't do the transformation. if (!IC.getDataLayout() || - SrcTy->getAddressSpace() != + SrcTy->getAddressSpace() != cast<PointerType>(CI->getType())->getAddressSpace() || IC.getDataLayout()->getTypeSizeInBits(SrcPTy) != IC.getDataLayout()->getTypeSizeInBits(DestPTy)) return 0; // Okay, we are casting from one integer or pointer type to another of - // the same size. Instead of casting the pointer before + // the same size. Instead of casting the pointer before // the store, cast the value to be stored. Value *NewCast; Value *SIOp0 = SI.getOperand(0); @@ -517,12 +517,12 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { if (SIOp0->getType()->isPointerTy()) opcode = Instruction::PtrToInt; } - + // SIOp0 is a pointer to aggregate and this is a store to the first field, // emit a GEP to index into its first field. if (!NewGEPIndices.empty()) CastOp = IC.Builder->CreateInBoundsGEP(CastOp, NewGEPIndices); - + NewCast = IC.Builder->CreateCast(opcode, SIOp0, CastDstTy, SIOp0->getName()+".c"); SI.setOperand(0, NewCast); @@ -541,7 +541,7 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { static bool equivalentAddressValues(Value *A, Value *B) { // Test if the values are trivially equivalent. if (A == B) return true; - + // Test if the values come form identical arithmetic instructions. // This uses isIdenticalToWhenDefined instead of isIdenticalTo because // its only used to compare two uses within the same basic block, which @@ -554,7 +554,7 @@ static bool equivalentAddressValues(Value *A, Value *B) { if (Instruction *BI = dyn_cast<Instruction>(B)) if (cast<Instruction>(A)->isIdenticalToWhenDefined(BI)) return true; - + // Otherwise they may not be equivalent. return false; } @@ -585,7 +585,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { // If the RHS is an alloca with a single use, zapify the store, making the // alloca dead. if (Ptr->hasOneUse()) { - if (isa<AllocaInst>(Ptr)) + if (isa<AllocaInst>(Ptr)) return EraseInstFromFunction(SI); if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) { if (isa<AllocaInst>(GEP->getOperand(0))) { @@ -608,8 +608,8 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { (isa<BitCastInst>(BBI) && BBI->getType()->isPointerTy())) { ScanInsts++; continue; - } - + } + if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) { // Prev store isn't volatile, and stores to the same location? if (PrevSI->isSimple() && equivalentAddressValues(PrevSI->getOperand(1), @@ -621,7 +621,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { } break; } - + // If this is a load, we have to stop. However, if the loaded value is from // the pointer we're loading and is producing the pointer we're storing, // then *this* store is dead (X = load P; store X -> P). @@ -629,12 +629,12 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr) && LI->isSimple()) return EraseInstFromFunction(SI); - + // Otherwise, this is a load from some other location. Stores before it // may not be dead. break; } - + // Don't skip over loads or things that can modify memory. if (BBI->mayWriteToMemory() || BBI->mayReadFromMemory()) break; @@ -664,11 +664,11 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (Instruction *Res = InstCombineStoreToCast(*this, SI)) return Res; - + // If this store is the last instruction in the basic block (possibly // excepting debug info instructions), and if the block ends with an // unconditional branch, try to move it to the successor block. - BBI = &SI; + BBI = &SI; do { ++BBI; } while (isa<DbgInfoIntrinsic>(BBI) || @@ -677,7 +677,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (BI->isUnconditional()) if (SimplifyStoreAtEndOfBlock(SI)) return 0; // xform done! - + return 0; } @@ -691,12 +691,12 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { /// bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BasicBlock *StoreBB = SI.getParent(); - + // Check to see if the successor block has exactly two incoming edges. If // so, see if the other predecessor contains a store to the same location. // if so, insert a PHI node (if needed) and move the stores down. BasicBlock *DestBB = StoreBB->getTerminator()->getSuccessor(0); - + // Determine whether Dest has exactly two predecessors and, if so, compute // the other predecessor. pred_iterator PI = pred_begin(DestBB); @@ -708,7 +708,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { if (++PI == pred_end(DestBB)) return false; - + P = *PI; if (P != StoreBB) { if (OtherBB) @@ -728,7 +728,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BranchInst *OtherBr = dyn_cast<BranchInst>(BBI); if (!OtherBr || BBI == OtherBB->begin()) return false; - + // If the other block ends in an unconditional branch, check for the 'if then // else' case. there is an instruction before the branch. StoreInst *OtherStore = 0; @@ -750,10 +750,10 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { } else { // Otherwise, the other block ended with a conditional branch. If one of the // destinations is StoreBB, then we have the if/then case. - if (OtherBr->getSuccessor(0) != StoreBB && + if (OtherBr->getSuccessor(0) != StoreBB && OtherBr->getSuccessor(1) != StoreBB) return false; - + // Okay, we know that OtherBr now goes to Dest and StoreBB, so this is an // if/then triangle. See if there is a store to the same ptr as SI that // lives in OtherBB. @@ -771,7 +771,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BBI == OtherBB->begin()) return false; } - + // In order to eliminate the store in OtherBr, we have to // make sure nothing reads or overwrites the stored value in // StoreBB. @@ -781,7 +781,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { return false; } } - + // Insert a PHI node now if we need it. Value *MergedVal = OtherStore->getOperand(0); if (MergedVal != SI.getOperand(0)) { @@ -790,7 +790,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { PN->addIncoming(OtherStore->getOperand(0), OtherBB); MergedVal = InsertNewInstBefore(PN, DestBB->front()); } - + // Advance to a place where it is safe to insert the new store and // insert it. BBI = DestBB->getFirstInsertionPt(); @@ -800,7 +800,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { SI.getOrdering(), SI.getSynchScope()); InsertNewInstBefore(NewSI, *BBI); - NewSI->setDebugLoc(OtherStore->getDebugLoc()); + NewSI->setDebugLoc(OtherStore->getDebugLoc()); // If the two stores had the same TBAA tag, preserve it. if (MDNode *TBAATag = SI.getMetadata(LLVMContext::MD_tbaa)) @@ -808,7 +808,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { OtherStore->getMetadata(LLVMContext::MD_tbaa)))) NewSI->setMetadata(LLVMContext::MD_tbaa, TBAATag); - + // Nuke the old stores. EraseInstFromFunction(SI); EraseInstFromFunction(*OtherStore); diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp index 8e4267f898..ecc9fc3e45 100644 --- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp +++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp @@ -28,7 +28,7 @@ static Value *simplifyValueKnownNonZero(Value *V, InstCombiner &IC) { // if this is safe. For example, the use could be in dynamically unreached // code. if (!V->hasOneUse()) return 0; - + bool MadeChange = false; // ((1 << A) >>u B) --> (1 << (A-B)) @@ -41,7 +41,7 @@ static Value *simplifyValueKnownNonZero(Value *V, InstCombiner &IC) { A = IC.Builder->CreateSub(A, B); return IC.Builder->CreateShl(PowerOf2, A); } - + // (PowerOfTwo >>u B) --> isExact since shifting out the result would make it // inexact. Similarly for <<. if (BinaryOperator *I = dyn_cast<BinaryOperator>(V)) @@ -52,12 +52,12 @@ static Value *simplifyValueKnownNonZero(Value *V, InstCombiner &IC) { I->setOperand(0, V2); MadeChange = true; } - + if (I->getOpcode() == Instruction::LShr && !I->isExact()) { I->setIsExact(); MadeChange = true; } - + if (I->getOpcode() == Instruction::Shl && !I->hasNoUnsignedWrap()) { I->setHasNoUnsignedWrap(); MadeChange = true; @@ -67,7 +67,7 @@ static Value *simplifyValueKnownNonZero(Value *V, InstCombiner &IC) { // TODO: Lots more we could do here: // If V is a phi node, we can call this on each of its operands. // "select cond, X, 0" can simplify to "X". - + return MadeChange ? V : 0; } @@ -84,12 +84,12 @@ static bool MultiplyOverflows(ConstantInt *C1, ConstantInt *C2, bool sign) { LHSExt = LHSExt.zext(W * 2); RHSExt = RHSExt.zext(W * 2); } - + APInt MulExt = LHSExt * RHSExt; - + if (!sign) return MulExt.ugt(APInt::getLowBitsSet(W * 2, W)); - + APInt Min = APInt::getSignedMinValue(W).sext(W * 2); APInt Max = APInt::getSignedMaxValue(W).sext(W * 2); return MulExt.slt(Min) || MulExt.sgt(Max); @@ -107,16 +107,16 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { if (match(Op1, m_AllOnes())) // X * -1 == 0 - X return BinaryOperator::CreateNeg(Op0, I.getName()); - + if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) { - + // ((X << C1)*C2) == (X * (C2 << C1)) if (BinaryOperator *SI = dyn_cast<BinaryOperator>(Op0)) if (SI->getOpcode() == Instruction::Shl) if (Constant *ShOp = dyn_cast<Constant>(SI->getOperand(1))) return BinaryOperator::CreateMul(SI->getOperand(0), ConstantExpr::getShl(CI, ShOp)); - + const APInt &Val = CI->getValue(); if (Val.isPowerOf2()) { // Replace X*(2^C) with X << C Constant *NewCst = ConstantInt::get(Op0->getType(), Val.logBase2()); @@ -125,7 +125,7 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { if (I.hasNoUnsignedWrap()) Shl->setHasNoUnsignedWrap(); return Shl; } - + // Canonicalize (X+C1)*CI -> X*CI+C1*CI. { Value *X; ConstantInt *C1; if (Op0->hasOneUse() && @@ -158,9 +158,9 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { } } } - + // Simplify mul instructions with a constant RHS. - if (isa<Constant>(Op1)) { + if (isa<Constant>(Op1)) { // Try to fold constant mul into select arguments. if (SelectInst *SI = dyn_cast<SelectInst>(Op0)) if (Instruction *R = FoldOpIntoSelect(I, SI)) @@ -181,7 +181,7 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { Value *Op1C = Op1; BinaryOperator *BO = dyn_cast<BinaryOperator>(Op0); if (!BO || - (BO->getOpcode() != Instruction::UDiv && + (BO->getOpcode() != Instruction::UDiv && BO->getOpcode() != Instruction::SDiv)) { Op1C = Op0; BO = dyn_cast<BinaryOperator>(Op1); @@ -227,14 +227,14 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { if (match(Op1, m_Shl(m_One(), m_Value(Y)))) return BinaryOperator::CreateShl(Op0, Y); } - + // If one of the operands of the multiply is a cast from a boolean value, then // we know the bool is either zero or one, so this is a 'masking' multiply. // X * Y (where Y is 0 or 1) -> X & (0-Y) if (!I.getType()->isVectorTy()) { // -2 is "-1 << 1" so it is all bits set except the low one. APInt Negative2(I.getType()->getPrimitiveSizeInBits(), (uint64_t)-2, true); - + Value *BoolCast = 0, *OtherOp = 0; if (MaskedValueIsZero(Op0, Negative2)) BoolCast = Op0, OtherOp = Op1; @@ -280,7 +280,7 @@ static void detectLog2OfHalf(Value *&Op, Value *&Y, IntrinsicInst *&Log2) { return; if (I->getOpcode() != Instruction::FMul || !I->hasUnsafeAlgebra()) return; - + ConstantFP *CFP = dyn_cast<ConstantFP>(I->getOperand(0)); if (CFP && CFP->isExactlyValue(0.5)) { Y = I->getOperand(1); @@ -289,14 +289,14 @@ static void detectLog2OfHalf(Value *&Op, Value *&Y, IntrinsicInst *&Log2) { CFP = dyn_cast<ConstantFP>(I->getOperand(1)); if (CFP && CFP->isExactlyValue(0.5)) Y = I->getOperand(0); -} +} /// Helper function of InstCombiner::visitFMul(BinaryOperator(). It returns /// true iff the given value is FMul or FDiv with one and only one operand /// being a normal constant (i.e. not Zero/NaN/Infinity). static bool isFMulOrFDivWithConstant(Value *V) { Instruction *I = dyn_cast<Instruction>(V); - if (!I || (I->getOpcode() != Instruction::FMul && + if (!I || (I->getOpcode() != Instruction::FMul && I->getOpcode() != Instruction::FDiv)) return false; @@ -318,10 +318,10 @@ static bool isNormalFp(const ConstantFP *C) { /// foldFMulConst() is a helper routine of InstCombiner::visitFMul(). /// The input \p FMulOrDiv is a FMul/FDiv with one and only one operand /// being a constant (i.e. isFMulOrFDivWithConstant(FMulOrDiv) == true). -/// This function is to simplify "FMulOrDiv * C" and returns the +/// This function is to simplify "FMulOrDiv * C" and returns the /// resulting expression. Note that this function could return NULL in /// case the constants cannot be folded into a normal floating-point. -/// +/// Value *InstCombiner::foldFMulConst(Instruction *FMulOrDiv, ConstantFP *C, Instruction *InsertBefore) { assert(isFMulOrFDivWithConstant(FMulOrDiv) && "V is invalid"); @@ -351,7 +351,7 @@ Value *InstCombiner::foldFMulConst(Instruction *FMulOrDiv, ConstantFP *C, if (isNormalFp(F)) { R = BinaryOperator::CreateFMul(Opnd0, F); } else { - // (X / C1) * C => X / (C1/C) + // (X / C1) * C => X / (C1/C) Constant *F = ConstantExpr::getFDiv(C1, C); if (isNormalFp(cast<ConstantFP>(F))) R = BinaryOperator::CreateFDiv(Opnd0, F); @@ -402,7 +402,7 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { return ReplaceInstUsesWith(I, V); } - // (MDC +/- C1) * C2 => (MDC * C2) +/- (C1 * C2) + // (MDC +/- C1) * C => (MDC * C) +/- (C1 * C) Instruction *FAddSub = dyn_cast<Instruction>(Op0); if (FAddSub && (FAddSub->getOpcode() == Instruction::FAdd || @@ -415,13 +415,13 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { if (C0) { std::swap(C0, C1); std::swap(Opnd0, Opnd1); - Swap = true; + Swap = true; } if (C1 && C1->getValueAPF().isNormal() && isFMulOrFDivWithConstant(Opnd0)) { - Value *M0 = ConstantExpr::getFMul(C1, C); - Value *M1 = isNormalFp(cast<ConstantFP>(M0)) ? + Value *M1 = ConstantExpr::getFMul(C1, C); + Value *M0 = isNormalFp(cast<ConstantFP>(M1)) ? foldFMulConst(cast<Instruction>(Opnd0), C, &I) : 0; if (M0 && M1) { @@ -495,7 +495,7 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { } // (X*Y) * X => (X*X) * Y where Y != X - // The purpose is two-fold: + // The purpose is two-fold: // 1) to form a power expression (of X). // 2) potentially shorten the critical path: After transformation, the // latency of the instruction Y is amortized by the expression of X*X, @@ -524,6 +524,35 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { } } + // B * (uitofp i1 C) -> select C, B, 0 + if (I.hasNoNaNs() && I.hasNoInfs() && I.hasNoSignedZeros()) { + Value *LHS = Op0, *RHS = Op1; + Value *B, *C; + if (!match(RHS, m_UIToFp(m_Value(C)))) + std::swap(LHS, RHS); + + if (match(RHS, m_UIToFp(m_Value(C))) && C->getType()->isIntegerTy(1)) { + B = LHS; + Value *Zero = ConstantFP::getNegativeZero(B->getType()); + return SelectInst::Create(C, B, Zero); + } + } + + // A * (1 - uitofp i1 C) -> select C, 0, A + if (I.hasNoNaNs() && I.hasNoInfs() && I.hasNoSignedZeros()) { + Value *LHS = Op0, *RHS = Op1; + Value *A, *C; + if (!match(RHS, m_FSub(m_FPOne(), m_UIToFp(m_Value(C))))) + std::swap(LHS, RHS); + + if (match(RHS, m_FSub(m_FPOne(), m_UIToFp(m_Value(C)))) && + C->getType()->isIntegerTy(1)) { + A = LHS; + Value *Zero = ConstantFP::getNegativeZero(A->getType()); + return SelectInst::Create(C, Zero, A); + } + } + if (!isa<Constant>(Op1)) std::swap(Opnd0, Opnd1); else @@ -537,7 +566,7 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { /// instruction. bool InstCombiner::SimplifyDivRemOfSelect(BinaryOperator &I) { SelectInst *SI = cast<SelectInst>(I.getOperand(1)); - + // div/rem X, (Cond ? 0 : Y) -> div/rem X, Y int NonNullOperand = -1; if (Constant *ST = dyn_cast<Constant>(SI->getOperand(1))) @@ -547,36 +576,36 @@ bool InstCombiner::SimplifyDivRemOfSelect(BinaryOperator &I) { if (Constant *ST = dyn_cast<Constant>(SI->getOperand(2))) if (ST->isNullValue()) NonNullOperand = 1; - + if (NonNullOperand == -1) return false; - + Value *SelectCond = SI->getOperand(0); - + // Change the div/rem to use 'Y' instead of the select. I.setOperand(1, SI->getOperand(NonNullOperand)); - + // Okay, we know we replace the operand of the div/rem with 'Y' with no // problem. However, the select, or the condition of the select may have // multiple uses. Based on our knowledge that the operand must be non-zero, // propagate the known value for the select into other uses of it, and // propagate a known value of the condition into its other users. - + // If the select and condition only have a single use, don't bother with this, // early exit. if (SI->use_empty() && SelectCond->hasOneUse()) return true; - + // Scan the current block backward, looking for other uses of SI. BasicBlock::iterator BBI = &I, BBFront = I.getParent()->begin(); - + while (BBI != BBFront) { --BBI; // If we found a call to a function, we can't assume it will return, so // information from below it cannot be propagated above it. if (isa<CallInst>(BBI) && !isa<IntrinsicInst>(BBI)) break; - + // Replace uses of the select or its condition with the known values. for (Instruction::op_iterator I = BBI->op_begin(), E = BBI->op_end(); I != E; ++I) { @@ -589,17 +618,17 @@ bool InstCombiner::SimplifyDivRemOfSelect(BinaryOperator &I) { Worklist.Add(BBI); } } - + // If we past the instruction, quit looking for it. if (&*BBI == SI) SI = 0; if (&*BBI == SelectCond) SelectCond = 0; - + // If we ran out of things to eliminate, break out of the loop. if (SelectCond == 0 && SI == 0) break; - + } return true; } @@ -617,7 +646,7 @@ Instruction *InstCombiner::commonIDivTransforms(BinaryOperator &I) { I.setOperand(1, V); return &I; } - + // Handle cases involving: [su]div X, (select Cond, Y, Z) // This does not apply for fdiv. if (isa<SelectInst>(Op1) && SimplifyDivRemOfSelect(I)) @@ -683,16 +712,16 @@ Instruction *InstCombiner::visitUDiv(BinaryOperator &I) { // Handle the integer div common cases if (Instruction *Common = commonIDivTransforms(I)) return Common; - - { + + { // X udiv 2^C -> X >> C // Check to see if this is an unsigned division with an exact power of 2, // if so, convert to a right shift. const APInt *C; if (match(Op1, m_Power2(C))) { BinaryOperator *LShr = - BinaryOperator::CreateLShr(Op0, - ConstantInt::get(Op0->getType(), + BinaryOperator::CreateLShr(Op0, + ConstantInt::get(Op0->getType(), C->logBase2())); if (I.isExact()) LShr->setIsExact(); return LShr; @@ -732,7 +761,7 @@ Instruction *InstCombiner::visitUDiv(BinaryOperator &I) { return BinaryOperator::CreateLShr(Op0, N); } } - + // udiv X, (Select Cond, C1, C2) --> Select Cond, (shr X, C1), (shr X, C2) // where C1&C2 are powers of two. { Value *Cond; const APInt *C1, *C2; @@ -740,11 +769,11 @@ Instruction *InstCombiner::visitUDiv(BinaryOperator &I) { // Construct the "on true" case of the select Value *TSI = Builder->CreateLShr(Op0, C1->logBase2(), Op1->getName()+".t", I.isExact()); - + // Construct the "on false" case of the select Value *FSI = Builder->CreateLShr(Op0, C2->logBase2(), Op1->getName()+".f", I.isExact()); - + // construct the select instruction and return it. return SelectInst::Create(Cond, TSI, FSI); } @@ -799,7 +828,7 @@ Instruction *InstCombiner::visitSDiv(BinaryOperator &I) { // X sdiv Y -> X udiv Y, iff X and Y don't have sign bit set return BinaryOperator::CreateUDiv(Op0, Op1, I.getName()); } - + if (match(Op1, m_Shl(m_Power2(), m_Value()))) { // X sdiv (1 << Y) -> X udiv (1 << Y) ( -> X u>> Y) // Safe because the only negative value (1 << Y) can take on is @@ -809,13 +838,13 @@ Instruction *InstCombiner::visitSDiv(BinaryOperator &I) { } } } - + return 0; } /// CvtFDivConstToReciprocal tries to convert X/C into X*1/C if C not a special /// FP value and: -/// 1) 1/C is exact, or +/// 1) 1/C is exact, or /// 2) reciprocal is allowed. /// If the convertion was successful, the simplified expression "X * 1/C" is /// returned; otherwise, NULL is returned. @@ -826,7 +855,7 @@ static Instruction *CvtFDivConstToReciprocal(Value *Dividend, const APFloat &FpVal = Divisor->getValueAPF(); APFloat Reciprocal(FpVal.getSemantics()); bool Cvt = FpVal.getExactInverse(&Reciprocal); - + if (!Cvt && AllowReciprocal && FpVal.isNormal()) { Reciprocal = APFloat(FpVal.getSemantics(), 1.0f); (void)Reciprocal.divide(FpVal, APFloat::rmNearestTiesToEven); @@ -870,10 +899,10 @@ Instruction *InstCombiner::visitFDiv(BinaryOperator &I) { Constant *C = ConstantExpr::getFMul(C1, C2); const APFloat &F = cast<ConstantFP>(C)->getValueAPF(); if (F.isNormal() && !F.isDenormal()) { - Res = CvtFDivConstToReciprocal(X, cast<ConstantFP>(C), + Res = CvtFDivConstToReciprocal(X, cast<ConstantFP>(C), AllowReciprocal); if (!Res) - Res = BinaryOperator::CreateFDiv(X, C); + Res = BinaryOperator::CreateFDiv(X, C); } } @@ -911,7 +940,7 @@ Instruction *InstCombiner::visitFDiv(BinaryOperator &I) { if (Fold) { const APFloat &FoldC = cast<ConstantFP>(Fold)->getValueAPF(); if (FoldC.isNormal() && !FoldC.isDenormal()) { - Instruction *R = CreateDiv ? + Instruction *R = CreateDiv ? BinaryOperator::CreateFDiv(Fold, X) : BinaryOperator::CreateFMul(X, Fold); R->setFastMathFlags(I.getFastMathFlags()); @@ -997,7 +1026,7 @@ Instruction *InstCombiner::visitURem(BinaryOperator &I) { if (Instruction *common = commonIRemTransforms(I)) return common; - + // X urem C^2 -> X and C-1 { const APInt *C; if (match(Op1, m_Power2(C))) @@ -1005,7 +1034,7 @@ Instruction *InstCombiner::visitURem(BinaryOperator &I) { ConstantInt::get(I.getType(), *C-1)); } - // Turn A % (C << N), where C is 2^k, into A & ((C << N)-1) + // Turn A % (C << N), where C is 2^k, into A & ((C << N)-1) if (match(Op1, m_Shl(m_Power2(), m_Value()))) { Constant *N1 = Constant::getAllOnesValue(I.getType()); Value *Add = Builder->CreateAdd(Op1, N1); @@ -1041,7 +1070,7 @@ Instruction *InstCombiner::visitSRem(BinaryOperator &I) { // Handle the integer rem common cases if (Instruction *Common = commonIRemTransforms(I)) return Common; - + if (Value *RHSNeg = dyn_castNegVal(Op1)) if (!isa<Constant>(RHSNeg) || (isa<ConstantInt>(RHSNeg) && diff --git a/lib/Transforms/InstCombine/InstCombinePHI.cpp b/lib/Transforms/InstCombine/InstCombinePHI.cpp index b0a998cca7..bd14e81c3f 100644 --- a/lib/Transforms/InstCombine/InstCombinePHI.cpp +++ b/lib/Transforms/InstCombine/InstCombinePHI.cpp @@ -27,10 +27,10 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { unsigned Opc = FirstInst->getOpcode(); Value *LHSVal = FirstInst->getOperand(0); Value *RHSVal = FirstInst->getOperand(1); - + Type *LHSType = LHSVal->getType(); Type *RHSType = RHSVal->getType(); - + bool isNUW = false, isNSW = false, isExact = false; if (OverflowingBinaryOperator *BO = dyn_cast<OverflowingBinaryOperator>(FirstInst)) { @@ -39,7 +39,7 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { } else if (PossiblyExactOperator *PEO = dyn_cast<PossiblyExactOperator>(FirstInst)) isExact = PEO->isExact(); - + // Scan to see if all operands are the same opcode, and all have one use. for (unsigned i = 1; i != PN.getNumIncomingValues(); ++i) { Instruction *I = dyn_cast<Instruction>(PN.getIncomingValue(i)); @@ -54,14 +54,14 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { if (CmpInst *CI = dyn_cast<CmpInst>(I)) if (CI->getPredicate() != cast<CmpInst>(FirstInst)->getPredicate()) return 0; - + if (isNUW) isNUW = cast<OverflowingBinaryOperator>(I)->hasNoUnsignedWrap(); if (isNSW) isNSW = cast<OverflowingBinaryOperator>(I)->hasNoSignedWrap(); if (isExact) isExact = cast<PossiblyExactOperator>(I)->isExact(); - + // Keep track of which operand needs a phi node. if (I->getOperand(0) != LHSVal) LHSVal = 0; if (I->getOperand(1) != RHSVal) RHSVal = 0; @@ -73,9 +73,9 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { // bad when the PHIs are in the header of a loop. if (!LHSVal && !RHSVal) return 0; - + // Otherwise, this is safe to transform! - + Value *InLHS = FirstInst->getOperand(0); Value *InRHS = FirstInst->getOperand(1); PHINode *NewLHS = 0, *NewRHS = 0; @@ -86,7 +86,7 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { InsertNewInstBefore(NewLHS, PN); LHSVal = NewLHS; } - + if (RHSVal == 0) { NewRHS = PHINode::Create(RHSType, PN.getNumIncomingValues(), FirstInst->getOperand(1)->getName() + ".pn"); @@ -94,7 +94,7 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { InsertNewInstBefore(NewRHS, PN); RHSVal = NewRHS; } - + // Add all operands to the new PHIs. if (NewLHS || NewRHS) { for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) { @@ -109,7 +109,7 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { } } } - + if (CmpInst *CIOp = dyn_cast<CmpInst>(FirstInst)) { CmpInst *NewCI = CmpInst::Create(CIOp->getOpcode(), CIOp->getPredicate(), LHSVal, RHSVal); @@ -129,8 +129,8 @@ Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) { Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { GetElementPtrInst *FirstInst =cast<GetElementPtrInst>(PN.getIncomingValue(0)); - - SmallVector<Value*, 16> FixedOperands(FirstInst->op_begin(), + + SmallVector<Value*, 16> FixedOperands(FirstInst->op_begin(), FirstInst->op_end()); // This is true if all GEP bases are allocas and if all indices into them are // constants. @@ -140,9 +140,9 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { // more than one phi, which leads to higher register pressure. This is // especially bad when the PHIs are in the header of a loop. bool NeededPhi = false; - + bool AllInBounds = true; - + // Scan to see if all operands are the same opcode, and all have one use. for (unsigned i = 1; i != PN.getNumIncomingValues(); ++i) { GetElementPtrInst *GEP= dyn_cast<GetElementPtrInst>(PN.getIncomingValue(i)); @@ -151,18 +151,18 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { return 0; AllInBounds &= GEP->isInBounds(); - + // Keep track of whether or not all GEPs are of alloca pointers. if (AllBasePointersAreAllocas && (!isa<AllocaInst>(GEP->getOperand(0)) || !GEP->hasAllConstantIndices())) AllBasePointersAreAllocas = false; - + // Compare the operand lists. for (unsigned op = 0, e = FirstInst->getNumOperands(); op != e; ++op) { if (FirstInst->getOperand(op) == GEP->getOperand(op)) continue; - + // Don't merge two GEPs when two operands differ (introducing phi nodes) // if one of the PHIs has a constant for the index. The index may be // substantially cheaper to compute for the constants, so making it a @@ -171,7 +171,7 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { if (isa<ConstantInt>(FirstInst->getOperand(op)) || isa<ConstantInt>(GEP->getOperand(op))) return 0; - + if (FirstInst->getOperand(op)->getType() !=GEP->getOperand(op)->getType()) return 0; @@ -186,7 +186,7 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { NeededPhi = true; } } - + // If all of the base pointers of the PHI'd GEPs are from allocas, don't // bother doing this transformation. At best, this will just save a bit of // offset calculation, but all the predecessors will have to materialize the @@ -195,11 +195,11 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { // which can usually all be folded into the load. if (AllBasePointersAreAllocas) return 0; - + // Otherwise, this is safe to transform. Insert PHI nodes for each operand // that is variable. SmallVector<PHINode*, 16> OperandPhis(FixedOperands.size()); - + bool HasAnyPHIs = false; for (unsigned i = 0, e = FixedOperands.size(); i != e; ++i) { if (FixedOperands[i]) continue; // operand doesn't need a phi. @@ -207,28 +207,28 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { PHINode *NewPN = PHINode::Create(FirstOp->getType(), e, FirstOp->getName()+".pn"); InsertNewInstBefore(NewPN, PN); - + NewPN->addIncoming(FirstOp, PN.getIncomingBlock(0)); OperandPhis[i] = NewPN; FixedOperands[i] = NewPN; HasAnyPHIs = true; } - + // Add all operands to the new PHIs. if (HasAnyPHIs) { for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) { GetElementPtrInst *InGEP =cast<GetElementPtrInst>(PN.getIncomingValue(i)); BasicBlock *InBB = PN.getIncomingBlock(i); - + for (unsigned op = 0, e = OperandPhis.size(); op != e; ++op) if (PHINode *OpPhi = OperandPhis[op]) OpPhi->addIncoming(InGEP->getOperand(op), InBB); } } - + Value *Base = FixedOperands[0]; - GetElementPtrInst *NewGEP = + GetElementPtrInst *NewGEP = GetElementPtrInst::Create(Base, makeArrayRef(FixedOperands).slice(1)); if (AllInBounds) NewGEP->setIsInBounds(); NewGEP->setDebugLoc(FirstInst->getDebugLoc()); @@ -246,11 +246,11 @@ Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) { /// to a register. static bool isSafeAndProfitableToSinkLoad(LoadInst *L) { BasicBlock::iterator BBI = L, E = L->getParent()->end(); - + for (++BBI; BBI != E; ++BBI) if (BBI->mayWriteToMemory()) return false; - + // Check for non-address taken alloca. If not address-taken already, it isn't // profitable to do this xform. if (AllocaInst *AI = dyn_cast<AllocaInst>(L->getOperand(0))) { @@ -266,11 +266,11 @@ static bool isSafeAndProfitableToSinkLoad(LoadInst *L) { isAddressTaken = true; break; } - + if (!isAddressTaken && AI->isStaticAlloca()) return false; } - + // If this load is a load from a GEP with a constant offset from an alloca, // then we don't want to sink it. In its present form, it will be // load [constant stack offset]. Sinking it will cause us to have to @@ -280,7 +280,7 @@ static bool isSafeAndProfitableToSinkLoad(LoadInst *L) { if (AllocaInst *AI = dyn_cast<AllocaInst>(GEP->getOperand(0))) if (AI->isStaticAlloca() && GEP->hasAllConstantIndices()) return false; - + return true; } @@ -300,41 +300,41 @@ Instruction *InstCombiner::FoldPHIArgLoadIntoPHI(PHINode &PN) { bool isVolatile = FirstLI->isVolatile(); unsigned LoadAlignment = FirstLI->getAlignment(); unsigned LoadAddrSpace = FirstLI->getPointerAddressSpace(); - + // We can't sink the load if the loaded value could be modified between the // load and the PHI. if (FirstLI->getParent() != PN.getIncomingBlock(0) || !isSafeAndProfitableToSinkLoad(FirstLI)) return 0; - + // If the PHI is of volatile loads and the load block has multiple // successors, sinking it would remove a load of the volatile value from // the path through the other successor. - if (isVolatile && + if (isVolatile && FirstLI->getParent()->getTerminator()->getNumSuccessors() != 1) return 0; - + // Check to see if all arguments are the same operation. for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) { LoadInst *LI = dyn_cast<LoadInst>(PN.getIncomingValue(i)); if (!LI || !LI->hasOneUse()) return 0; - - // We can't sink the load if the loaded value could be modified between + + // We can't sink the load if the loaded value could be modified between // the load and the PHI. if (LI->isVolatile() != isVolatile || LI->getParent() != PN.getIncomingBlock(i) || LI->getPointerAddressSpace() != LoadAddrSpace || !isSafeAndProfitableToSinkLoad(LI)) return 0; - + // If some of the loads have an alignment specified but not all of them, // we can't do the transformation. if ((LoadAlignment != 0) != (LI->getAlignment() != 0)) return 0; - + LoadAlignment = std::min(LoadAlignment, LI->getAlignment()); - + // If the PHI is of volatile loads and the load block has multiple // successors, sinking it would remove a load of the volatile value from // the path through the other successor. @@ -342,16 +342,16 @@ Instruction *InstCombiner::FoldPHIArgLoadIntoPHI(PHINode &PN) { LI->getParent()->getTerminator()->getNumSuccessors() != 1) return 0; } - + // Okay, they are all the same operation. Create a new PHI node of the // correct type, and PHI together all of the LHS's of the instructions. PHINode *NewPN = PHINode::Create(FirstLI->getOperand(0)->getType(), PN.getNumIncomingValues(), PN.getName()+".in"); - + Value *InVal = FirstLI->getOperand(0); NewPN->addIncoming(InVal, PN.getIncomingBlock(0)); - + // Add all operands to the new PHI. for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) { Value *NewInVal = cast<LoadInst>(PN.getIncomingValue(i))->getOperand(0); @@ -359,7 +359,7 @@ Instruction *InstCombiner::FoldPHIArgLoadIntoPHI(PHINode &PN) { InVal = 0; NewPN->addIncoming(NewInVal, PN.getIncomingBlock(i)); } - + Value *PhiVal; if (InVal) { // The new PHI unions all of the same values together. This is really @@ -370,14 +370,14 @@ Instruction *InstCombiner::FoldPHIArgLoadIntoPHI(PHINode &PN) { InsertNewInstBefore(NewPN, PN); PhiVal = NewPN; } - + // If this was a volatile load that we are merging, make sure to loop through // and mark all the input loads as non-volatile. If we don't do this, we will // insert a new volatile load and the old ones will not be deletable. if (isVolatile) for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) cast<LoadInst>(PN.getIncomingValue(i))->setVolatile(false); - + LoadInst *NewLI = new LoadInst(PhiVal, "", isVolatile, LoadAlignment); NewLI->setDebugLoc(FirstLI->getDebugLoc()); return NewLI; @@ -395,7 +395,7 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { return FoldPHIArgGEPIntoPHI(PN); if (isa<LoadInst>(FirstInst)) return FoldPHIArgLoadIntoPHI(PN); - + // Scan the instruction, looking for input operations that can be folded away. // If all input operands to the phi are the same instruction (e.g. a cast from // the same type or "+42") we can pull the operation through the PHI, reducing @@ -403,7 +403,7 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { Constant *ConstantOp = 0; Type *CastSrcTy = 0; bool isNUW = false, isNSW = false, isExact = false; - + if (isa<CastInst>(FirstInst)) { CastSrcTy = FirstInst->getOperand(0)->getType(); @@ -414,12 +414,12 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { return 0; } } else if (isa<BinaryOperator>(FirstInst) || isa<CmpInst>(FirstInst)) { - // Can fold binop, compare or shift here if the RHS is a constant, + // Can fold binop, compare or shift here if the RHS is a constant, // otherwise call FoldPHIArgBinOpIntoPHI. ConstantOp = dyn_cast<Constant>(FirstInst->getOperand(1)); if (ConstantOp == 0) return FoldPHIArgBinOpIntoPHI(PN); - + if (OverflowingBinaryOperator *BO = dyn_cast<OverflowingBinaryOperator>(FirstInst)) { isNUW = BO->hasNoUnsignedWrap(); @@ -442,7 +442,7 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { } else if (I->getOperand(1) != ConstantOp) { return 0; } - + if (isNUW) isNUW = cast<OverflowingBinaryOperator>(I)->hasNoUnsignedWrap(); if (isNSW) @@ -486,7 +486,7 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { NewCI->setDebugLoc(FirstInst->getDebugLoc()); return NewCI; } - + if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(FirstInst)) { BinOp = BinaryOperator::Create(BinOp->getOpcode(), PhiVal, ConstantOp); if (isNUW) BinOp->setHasNoUnsignedWrap(); @@ -495,7 +495,7 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) { BinOp->setDebugLoc(FirstInst->getDebugLoc()); return BinOp; } - + CmpInst *CIOp = cast<CmpInst>(FirstInst); CmpInst *NewCI = CmpInst::Create(CIOp->getOpcode(), CIOp->getPredicate(), PhiVal, ConstantOp); @@ -513,7 +513,7 @@ static bool DeadPHICycle(PHINode *PN, // Remember this node, and if we find the cycle, return. if (!PotentiallyDeadPHIs.insert(PN)) return true; - + // Don't scan crazily complex things. if (PotentiallyDeadPHIs.size() == 16) return false; @@ -527,16 +527,16 @@ static bool DeadPHICycle(PHINode *PN, /// PHIsEqualValue - Return true if this phi node is always equal to /// NonPhiInVal. This happens with mutually cyclic phi nodes like: /// z = some value; x = phi (y, z); y = phi (x, z) -static bool PHIsEqualValue(PHINode *PN, Value *NonPhiInVal, +static bool PHIsEqualValue(PHINode *PN, Value *NonPhiInVal, SmallPtrSet<PHINode*, 16> &ValueEqualPHIs) { // See if we already saw this PHI node. if (!ValueEqualPHIs.insert(PN)) return true; - + // Don't scan crazily complex things. if (ValueEqualPHIs.size() == 16) return false; - + // Scan the operands to see if they are either phi nodes or are equal to // the value. for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { @@ -547,7 +547,7 @@ static bool PHIsEqualValue(PHINode *PN, Value *NonPhiInVal, } else if (Op != NonPhiInVal) return false; } - + return true; } @@ -557,10 +557,10 @@ struct PHIUsageRecord { unsigned PHIId; // The ID # of the PHI (something determinstic to sort on) unsigned Shift; // The amount shifted. Instruction *Inst; // The trunc instruction. - + PHIUsageRecord(unsigned pn, unsigned Sh, Instruction *User) : PHIId(pn), Shift(Sh), Inst(User) {} - + bool operator<(const PHIUsageRecord &RHS) const { if (PHIId < RHS.PHIId) return true; if (PHIId > RHS.PHIId) return false; @@ -570,15 +570,15 @@ struct PHIUsageRecord { RHS.Inst->getType()->getPrimitiveSizeInBits(); } }; - + struct LoweredPHIRecord { PHINode *PN; // The PHI that was lowered. unsigned Shift; // The amount shifted. unsigned Width; // The width extracted. - + LoweredPHIRecord(PHINode *pn, unsigned Sh, Type *Ty) : PN(pn), Shift(Sh), Width(Ty->getPrimitiveSizeInBits()) {} - + // Ctor form used by DenseMap. LoweredPHIRecord(PHINode *pn, unsigned Sh) : PN(pn), Shift(Sh), Width(0) {} @@ -621,20 +621,20 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { // PHIUsers - Keep track of all of the truncated values extracted from a set // of PHIs, along with their offset. These are the things we want to rewrite. SmallVector<PHIUsageRecord, 16> PHIUsers; - + // PHIs are often mutually cyclic, so we keep track of a whole set of PHI // nodes which are extracted from. PHIsToSlice is a set we use to avoid // revisiting PHIs, PHIsInspected is a ordered list of PHIs that we need to // check the uses of (to ensure they are all extracts). SmallVector<PHINode*, 8> PHIsToSlice; SmallPtrSet<PHINode*, 8> PHIsInspected; - + PHIsToSlice.push_back(&FirstPhi); PHIsInspected.insert(&FirstPhi); - + for (unsigned PHIId = 0; PHIId != PHIsToSlice.size(); ++PHIId) { PHINode *PN = PHIsToSlice[PHIId]; - + // Scan the input list of the PHI. If any input is an invoke, and if the // input is defined in the predecessor, then we won't be split the critical // edge which is required to insert a truncate. Because of this, we have to @@ -644,85 +644,85 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { if (II == 0) continue; if (II->getParent() != PN->getIncomingBlock(i)) continue; - + // If we have a phi, and if it's directly in the predecessor, then we have // a critical edge where we need to put the truncate. Since we can't // split the edge in instcombine, we have to bail out. return 0; } - - + + for (Value::use_iterator UI = PN->use_begin(), E = PN->use_end(); UI != E; ++UI) { Instruction *User = cast<Instruction>(*UI); - + // If the user is a PHI, inspect its uses recursively. if (PHINode *UserPN = dyn_cast<PHINode>(User)) { if (PHIsInspected.insert(UserPN)) PHIsToSlice.push_back(UserPN); continue; } - + // Truncates are always ok. if (isa<TruncInst>(User)) { PHIUsers.push_back(PHIUsageRecord(PHIId, 0, User)); continue; } - + // Otherwise it must be a lshr which can only be used by one trunc. if (User->getOpcode() != Instruction::LShr || !User->hasOneUse() || !isa<TruncInst>(User->use_back()) || !isa<ConstantInt>(User->getOperand(1))) return 0; - + unsigned Shift = cast<ConstantInt>(User->getOperand(1))->getZExtValue(); PHIUsers.push_back(PHIUsageRecord(PHIId, Shift, User->use_back())); } } - + // If we have no users, they must be all self uses, just nuke the PHI. if (PHIUsers.empty()) return ReplaceInstUsesWith(FirstPhi, UndefValue::get(FirstPhi.getType())); - + // If this phi node is transformable, create new PHIs for all the pieces // extracted out of it. First, sort the users by their offset and size. array_pod_sort(PHIUsers.begin(), PHIUsers.end()); - + DEBUG(errs() << "SLICING UP PHI: " << FirstPhi << '\n'; for (unsigned i = 1, e = PHIsToSlice.size(); i != e; ++i) errs() << "AND USER PHI #" << i << ": " << *PHIsToSlice[i] <<'\n'; ); - + // PredValues - This is a temporary used when rewriting PHI nodes. It is // hoisted out here to avoid construction/destruction thrashing. DenseMap<BasicBlock*, Value*> PredValues; - + // ExtractedVals - Each new PHI we introduce is saved here so we don't // introduce redundant PHIs. DenseMap<LoweredPHIRecord, PHINode*> ExtractedVals; - + for (unsigned UserI = 0, UserE = PHIUsers.size(); UserI != UserE; ++UserI) { unsigned PHIId = PHIUsers[UserI].PHIId; PHINode *PN = PHIsToSlice[PHIId]; unsigned Offset = PHIUsers[UserI].Shift; Type *Ty = PHIUsers[UserI].Inst->getType(); - + PHINode *EltPHI; - + // If we've already lowered a user like this, reuse the previously lowered // value. if ((EltPHI = ExtractedVals[LoweredPHIRecord(PN, Offset, Ty)]) == 0) { - + // Otherwise, Create the new PHI node for this user. EltPHI = PHINode::Create(Ty, PN->getNumIncomingValues(), PN->getName()+".off"+Twine(Offset), PN); assert(EltPHI->getType() != PN->getType() && "Truncate didn't shrink phi?"); - + for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { BasicBlock *Pred = PN->getIncomingBlock(i); Value *&PredVal = PredValues[Pred]; - + // If we already have a value for this predecessor, reuse it. if (PredVal) { EltPHI->addIncoming(PredVal, Pred); @@ -736,7 +736,7 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { EltPHI->addIncoming(PredVal, Pred); continue; } - + if (PHINode *InPHI = dyn_cast<PHINode>(PN)) { // If the incoming value was a PHI, and if it was one of the PHIs we // already rewrote it, just use the lowered value. @@ -746,7 +746,7 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { continue; } } - + // Otherwise, do an extract in the predecessor. Builder->SetInsertPoint(Pred, Pred->getTerminator()); Value *Res = InVal; @@ -756,7 +756,7 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { Res = Builder->CreateTrunc(Res, Ty, "extract.t"); PredVal = Res; EltPHI->addIncoming(Res, Pred); - + // If the incoming value was a PHI, and if it was one of the PHIs we are // rewriting, we will ultimately delete the code we inserted. This // means we need to revisit that PHI to make sure we extract out the @@ -765,22 +765,22 @@ Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) { if (PHIsInspected.count(OldInVal)) { unsigned RefPHIId = std::find(PHIsToSlice.begin(),PHIsToSlice.end(), OldInVal)-PHIsToSlice.begin(); - PHIUsers.push_back(PHIUsageRecord(RefPHIId, Offset, + PHIUsers.push_back(PHIUsageRecord(RefPHIId, Offset, cast<Instruction>(Res))); ++UserE; } } PredValues.clear(); - + DEBUG(errs() << " Made element PHI for offset " << Offset << ": " << *EltPHI << '\n'); ExtractedVals[LoweredPHIRecord(PN, Offset, Ty)] = EltPHI; } - + // Replace the use of this piece with the PHI node. ReplaceInstUsesWith(*PHIUsers[UserI].Inst, EltPHI); } - + // Replace all the remaining uses of the PHI nodes (self uses and the lshrs) // with undefs. Value *Undef = UndefValue::get(FirstPhi.getType()); @@ -818,7 +818,7 @@ Instruction *InstCombiner::visitPHINode(PHINode &PN) { if (DeadPHICycle(PU, PotentiallyDeadPHIs)) return ReplaceInstUsesWith(PN, UndefValue::get(PN.getType())); } - + // If this phi has a single use, and if that use just computes a value for // the next iteration of a loop, delete the phi. This occurs with unused // induction variables, e.g. "for (int j = 0; ; ++j);". Detecting this @@ -847,7 +847,7 @@ Instruction *InstCombiner::visitPHINode(PHINode &PN) { if (InValNo != NumIncomingVals) { Value *NonPhiInVal = PN.getIncomingValue(InValNo); - + // Scan the rest of the operands to see if there are any conflicts, if so // there is no need to recursively scan other phis. for (++InValNo; InValNo != NumIncomingVals; ++InValNo) { @@ -855,7 +855,7 @@ Instruction *InstCombiner::visitPHINode(PHINode &PN) { if (OpVal != NonPhiInVal && !isa<PHINode>(OpVal)) break; } - + // If we scanned over all operands, then we have one unique value plus // phi values. Scan PHI nodes to see if they all merge in each other or // the value. @@ -899,6 +899,6 @@ Instruction *InstCombiner::visitPHINode(PHINode &PN) { !TD->isLegalInteger(PN.getType()->getPrimitiveSizeInBits())) if (Instruction *Res = SliceUpIllegalIntegerPHI(PN)) return Res; - + return 0; } diff --git a/lib/Transforms/InstCombine/InstCombineSelect.cpp b/lib/Transforms/InstCombine/InstCombineSelect.cpp index a262d711d3..59502fb988 100644 --- a/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -127,13 +127,14 @@ Instruction *InstCombiner::FoldSelectOpOp(SelectInst &SI, Instruction *TI, // If this is a non-volatile load or a cast from the same type, // merge. if (TI->isCast()) { - if (TI->getOperand(0)->getType() != FI->getOperand(0)->getType()) + Type *FIOpndTy = FI->getOperand(0)->getType(); + if (TI->getOperand(0)->getType() != FIOpndTy) return 0; // 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() && CondTy->getVectorNumElements() != - FI->getOperand(0)->getType()->getVectorNumElements()) + if (CondTy->isVectorTy() && (!FIOpndTy->isVectorTy() || + CondTy->getVectorNumElements() != FIOpndTy->getVectorNumElements())) return 0; } else { return 0; // unknown unary op. @@ -349,6 +350,68 @@ static Value *SimplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp, return 0; } +/// foldSelectICmpAndOr - 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 SelectInst &SI, Value *TrueVal, + Value *FalseVal, + InstCombiner::BuilderTy *Builder) { + const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition()); + if (!IC || !IC->isEquality()) + return 0; + + Value *CmpLHS = IC->getOperand(0); + Value *CmpRHS = IC->getOperand(1); + + if (!match(CmpRHS, m_Zero())) + return 0; + + Value *X; + const APInt *C1; + if (!match(CmpLHS, m_And(m_Value(X), m_Power2(C1)))) + return 0; + + 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 0; + + Value *V = CmpLHS; + Value *Y = OrOnFalseVal ? TrueVal : FalseVal; + + unsigned C1Log = C1->logBase2(); + unsigned C2Log = C2->logBase2(); + 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()); + + ICmpInst::Predicate Pred = IC->getPredicate(); + if ((Pred == ICmpInst::ICMP_NE && OrOnFalseVal) || + (Pred == ICmpInst::ICMP_EQ && OrOnTrueVal)) + V = Builder->CreateXor(V, *C2); + + return Builder->CreateOr(V, Y); +} + /// visitSelectInstWithICmp - Visit a SelectInst that has an /// ICmpInst as its first operand. /// @@ -520,6 +583,9 @@ Instruction *InstCombiner::visitSelectInstWithICmp(SelectInst &SI, } } + if (Value *V = foldSelectICmpAndOr(SI, TrueVal, FalseVal, Builder)) + return ReplaceInstUsesWith(SI, V); + return Changed ? &SI : 0; } @@ -675,7 +741,8 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { // Change: A = select B, false, C --> A = and !B, C Value *NotCond = Builder->CreateNot(CondVal, "not."+CondVal->getName()); return BinaryOperator::CreateAnd(NotCond, FalseVal); - } else if (ConstantInt *C = dyn_cast<ConstantInt>(FalseVal)) { + } + if (ConstantInt *C = dyn_cast<ConstantInt>(FalseVal)) { if (C->getZExtValue() == false) { // Change: A = select B, C, false --> A = and B, C return BinaryOperator::CreateAnd(CondVal, TrueVal); @@ -689,14 +756,14 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { // select a, a, b -> a|b if (CondVal == TrueVal) return BinaryOperator::CreateOr(CondVal, FalseVal); - else if (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); - else if (match(FalseVal, m_Not(m_Specific(CondVal)))) + if (match(FalseVal, m_Not(m_Specific(CondVal)))) return BinaryOperator::CreateOr(TrueVal, FalseVal); } @@ -837,7 +904,7 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { Value *NewFalseOp = NegVal; if (AddOp != TI) std::swap(NewTrueOp, NewFalseOp); - Value *NewSel = + Value *NewSel = Builder->CreateSelect(CondVal, NewTrueOp, NewFalseOp, SI.getName() + ".p"); @@ -861,7 +928,7 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { Value *LHS, *RHS, *LHS2, *RHS2; if (SelectPatternFlavor SPF = MatchSelectPattern(&SI, LHS, RHS)) { if (SelectPatternFlavor SPF2 = MatchSelectPattern(LHS, LHS2, RHS2)) - if (Instruction *R = FoldSPFofSPF(cast<Instruction>(LHS),SPF2,LHS2,RHS2, + if (Instruction *R = FoldSPFofSPF(cast<Instruction>(LHS),SPF2,LHS2,RHS2, SI, SPF, RHS)) return R; if (SelectPatternFlavor SPF2 = MatchSelectPattern(RHS, LHS2, RHS2)) @@ -907,7 +974,7 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { return &SI; } - if (VectorType *VecTy = dyn_cast<VectorType>(SI.getType())) { + if (VectorType* VecTy = dyn_cast<VectorType>(SI.getType())) { unsigned VWidth = VecTy->getNumElements(); APInt UndefElts(VWidth, 0); APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth)); @@ -917,24 +984,6 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { return &SI; } - if (ConstantVector *CV = dyn_cast<ConstantVector>(CondVal)) { - // Form a shufflevector instruction. - SmallVector<Constant *, 8> Mask(VWidth); - Type *Int32Ty = Type::getInt32Ty(CV->getContext()); - for (unsigned i = 0; i != VWidth; ++i) { - Constant *Elem = cast<Constant>(CV->getOperand(i)); - if (ConstantInt *E = dyn_cast<ConstantInt>(Elem)) - Mask[i] = ConstantInt::get(Int32Ty, i + (E->isZero() ? VWidth : 0)); - else if (isa<UndefValue>(Elem)) - Mask[i] = UndefValue::get(Int32Ty); - else - return 0; - } - Constant *MaskVal = ConstantVector::get(Mask); - Value *V = Builder->CreateShuffleVector(TrueVal, FalseVal, MaskVal); - return ReplaceInstUsesWith(SI, V); - } - if (isa<ConstantAggregateZero>(CondVal)) { return ReplaceInstUsesWith(SI, FalseVal); } diff --git a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp index 4f71db1a4b..4301ddb5aa 100644 --- a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp +++ b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp @@ -105,6 +105,75 @@ static Value *FindScalarElement(Value *V, unsigned EltNo) { return 0; } +// If we have a PHI node with a vector type that has only 2 uses: feed +// itself and be an operand of extractelemnt at a constant location, +// try to replace the PHI of the vector type with a PHI of a scalar type +Instruction *InstCombiner::scalarizePHI(ExtractElementInst &EI, PHINode *PN) { + // Verify that the PHI node has exactly 2 uses. Otherwise return NULL. + if (!PN->hasNUses(2)) + return NULL; + + // If so, it's known at this point that one operand is PHI and the other is + // an extractelement node. Find the PHI user that is not the extractelement + // node. + Value::use_iterator iu = PN->use_begin(); + Instruction *PHIUser = dyn_cast<Instruction>(*iu); + if (PHIUser == cast<Instruction>(&EI)) + PHIUser = cast<Instruction>(*(++iu)); + + // Verify that this PHI user has one use, which is the PHI itself, + // and that it is a binary operation which is cheap to scalarize. + // otherwise return NULL. + if (!PHIUser->hasOneUse() || !(PHIUser->use_back() == PN) || + !(isa<BinaryOperator>(PHIUser)) || + !CheapToScalarize(PHIUser, true)) + return NULL; + + // Create a scalar PHI node that will replace the vector PHI node + // just before the current PHI node. + PHINode * scalarPHI = cast<PHINode>( + InsertNewInstWith(PHINode::Create(EI.getType(), + PN->getNumIncomingValues(), ""), *PN)); + // Scalarize each PHI operand. + for (unsigned i=0; i < PN->getNumIncomingValues(); i++) { + Value *PHIInVal = PN->getIncomingValue(i); + BasicBlock *inBB = PN->getIncomingBlock(i); + Value *Elt = EI.getIndexOperand(); + // If the operand is the PHI induction variable: + if (PHIInVal == PHIUser) { + // Scalarize the binary operation. Its first operand is the + // scalar PHI and the second operand is extracted from the other + // vector operand. + BinaryOperator *B0 = cast<BinaryOperator>(PHIUser); + unsigned opId = (B0->getOperand(0) == PN) ? 1: 0; + Value *Op = Builder->CreateExtractElement( + B0->getOperand(opId), Elt, B0->getOperand(opId)->getName()+".Elt"); + Value *newPHIUser = InsertNewInstWith( + BinaryOperator::Create(B0->getOpcode(), scalarPHI,Op), + *B0); + scalarPHI->addIncoming(newPHIUser, inBB); + } else { + // Scalarize PHI input: + Instruction *newEI = + ExtractElementInst::Create(PHIInVal, Elt, ""); + // Insert the new instruction into the predecessor basic block. + Instruction *pos = dyn_cast<Instruction>(PHIInVal); + BasicBlock::iterator InsertPos; + if (pos && !isa<PHINode>(pos)) { + InsertPos = pos; + ++InsertPos; + } else { + InsertPos = inBB->getFirstInsertionPt(); + } + + InsertNewInstWith(newEI, *InsertPos); + + scalarPHI->addIncoming(newEI, inBB); + } + } + return ReplaceInstUsesWith(EI, scalarPHI); +} + Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) { // If vector val is constant with all elements the same, replace EI with // that element. We handle a known element # below. @@ -149,6 +218,14 @@ Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) { if (Value *Elt = FindScalarElement(BCI->getOperand(0), IndexVal)) return new BitCastInst(Elt, EI.getType()); } + + // If there's a vector PHI feeding a scalar use through this extractelement + // instruction, try to scalarize the PHI. + if (PHINode *PN = dyn_cast<PHINode>(EI.getOperand(0))) { + Instruction *scalarPHI = scalarizePHI(EI, PN); + if (scalarPHI) + return (scalarPHI); + } } if (Instruction *I = dyn_cast<Instruction>(EI.getOperand(0))) { @@ -201,10 +278,10 @@ Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) { } else if (CastInst *CI = dyn_cast<CastInst>(I)) { // Canonicalize extractelement(cast) -> cast(extractelement) // bitcasts can change the number of vector elements and they cost nothing - if (CI->hasOneUse() && EI.hasOneUse() && - (CI->getOpcode() != Instruction::BitCast)) { + if (CI->hasOneUse() && (CI->getOpcode() != Instruction::BitCast)) { Value *EE = Builder->CreateExtractElement(CI->getOperand(0), EI.getIndexOperand()); + Worklist.AddValue(EE); return CastInst::Create(CI->getOpcode(), EE, EI.getType()); } } @@ -336,6 +413,10 @@ static Value *CollectShuffleElements(Value *V, SmallVectorImpl<Constant*> &Mask, if (VecOp == RHS) { Value *V = CollectShuffleElements(EI->getOperand(0), Mask, RHS); + // Update Mask to reflect that `ScalarOp' has been inserted at + // position `InsertedIdx' within the vector returned by IEI. + Mask[InsertedIdx % NumElts] = Mask[ExtractedIdx]; + // Everything but the extracted element is replaced with the RHS. for (unsigned i = 0; i != NumElts; ++i) { if (i != InsertedIdx) diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp index c6115e3e91..ec10751202 100644 --- a/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -1483,7 +1483,7 @@ Instruction *InstCombiner::visitAllocSite(Instruction &MI) { Module *M = II->getParent()->getParent()->getParent(); Function *F = Intrinsic::getDeclaration(M, Intrinsic::donothing); InvokeInst::Create(F, II->getNormalDest(), II->getUnwindDest(), - ArrayRef<Value *>(), "", II->getParent()); + None, "", II->getParent()); } return EraseInstFromFunction(MI); } |