diff options
Diffstat (limited to 'lib/Transforms/InstCombine')
5 files changed, 106 insertions, 13 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp index c6d60d6..3c5781c 100644 --- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -150,7 +150,9 @@ namespace { 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); @@ -159,6 +161,7 @@ namespace { 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); @@ -388,6 +391,78 @@ 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"); @@ -471,7 +546,8 @@ 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) { @@ -627,7 +703,8 @@ 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 +716,22 @@ 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; } diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 4332467..990cbc3 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) { diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index a960ab2..d162223 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; diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp index bad46b4..32fdb9b 100644 --- a/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -1333,13 +1333,14 @@ 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); - if (Amt != 0 && RHSV.countTrailingZeros() >= Amt) { + if (LHSI->hasOneUse() && + Amt != 0 && RHSV.countTrailingZeros() >= Amt) { Type *NTy = IntegerType::get(ICI.getContext(), TypeBits - Amt); Constant *NCI = ConstantExpr::getTrunc( ConstantExpr::getAShr(RHS, diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp index 8e4267f..173f2bf 100644 --- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp +++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp @@ -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 || @@ -420,8 +420,8 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) { 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) { |