diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineAddSub.cpp')
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineAddSub.cpp | 88 |
1 files changed, 19 insertions, 69 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp index 05e702f..99b62f8 100644 --- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -170,10 +170,11 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) { // -A + B --> B - A // -A + -B --> -(A + B) if (Value *LHSV = dyn_castNegVal(LHS)) { - if (Value *RHSV = dyn_castNegVal(RHS)) { - Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum"); - return BinaryOperator::CreateNeg(NewAdd); - } + if (!isa<Constant>(RHS)) + if (Value *RHSV = dyn_castNegVal(RHS)) { + Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum"); + return BinaryOperator::CreateNeg(NewAdd); + } return BinaryOperator::CreateSub(RHS, LHSV); } @@ -329,6 +330,20 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) { } } + // Check for (x & y) + (x ^ y) + { + Value *A = 0, *B = 0; + if (match(RHS, m_Xor(m_Value(A), m_Value(B))) && + (match(LHS, m_And(m_Specific(A), m_Specific(B))) || + match(LHS, m_And(m_Specific(B), m_Specific(A))))) + return BinaryOperator::CreateOr(A, B); + + if (match(LHS, m_Xor(m_Value(A), m_Value(B))) && + (match(RHS, m_And(m_Specific(A), m_Specific(B))) || + match(RHS, m_And(m_Specific(B), m_Specific(A))))) + return BinaryOperator::CreateOr(A, B); + } + return Changed ? &I : 0; } @@ -406,66 +421,6 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) { } -/// EmitGEPOffset - Given a getelementptr instruction/constantexpr, emit the -/// code necessary to compute the offset from the base pointer (without adding -/// in the base pointer). Return the result as a signed integer of intptr size. -Value *InstCombiner::EmitGEPOffset(User *GEP) { - TargetData &TD = *getTargetData(); - gep_type_iterator GTI = gep_type_begin(GEP); - Type *IntPtrTy = TD.getIntPtrType(GEP->getContext()); - Value *Result = Constant::getNullValue(IntPtrTy); - - // If the GEP is inbounds, we know that none of the addressing operations will - // overflow in an unsigned sense. - bool isInBounds = cast<GEPOperator>(GEP)->isInBounds(); - - // Build a mask for high order bits. - unsigned IntPtrWidth = TD.getPointerSizeInBits(); - uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth); - - for (User::op_iterator i = GEP->op_begin() + 1, e = GEP->op_end(); i != e; - ++i, ++GTI) { - Value *Op = *i; - uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType()) & PtrSizeMask; - if (ConstantInt *OpC = dyn_cast<ConstantInt>(Op)) { - if (OpC->isZero()) continue; - - // Handle a struct index, which adds its field offset to the pointer. - if (StructType *STy = dyn_cast<StructType>(*GTI)) { - Size = TD.getStructLayout(STy)->getElementOffset(OpC->getZExtValue()); - - if (Size) - Result = Builder->CreateAdd(Result, ConstantInt::get(IntPtrTy, Size), - GEP->getName()+".offs"); - continue; - } - - Constant *Scale = ConstantInt::get(IntPtrTy, Size); - Constant *OC = - ConstantExpr::getIntegerCast(OpC, IntPtrTy, true /*SExt*/); - Scale = ConstantExpr::getMul(OC, Scale, isInBounds/*NUW*/); - // Emit an add instruction. - Result = Builder->CreateAdd(Result, Scale, GEP->getName()+".offs"); - continue; - } - // Convert to correct type. - if (Op->getType() != IntPtrTy) - Op = Builder->CreateIntCast(Op, IntPtrTy, true, Op->getName()+".c"); - if (Size != 1) { - // We'll let instcombine(mul) convert this to a shl if possible. - Op = Builder->CreateMul(Op, ConstantInt::get(IntPtrTy, Size), - GEP->getName()+".idx", isInBounds /*NUW*/); - } - - // Emit an add instruction. - Result = Builder->CreateAdd(Op, Result, GEP->getName()+".offs"); - } - return Result; -} - - - - /// Optimize pointer differences into the same array into a size. Consider: /// &A[10] - &A[0]: we should compile this to "10". LHS/RHS are the pointer /// operands to the ptrtoint instructions for the LHS/RHS of the subtract. @@ -589,11 +544,6 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { if (Instruction *R = FoldOpIntoSelect(I, SI)) return R; - // C - zext(bool) -> bool ? C - 1 : C - if (ZExtInst *ZI = dyn_cast<ZExtInst>(Op1)) - if (ZI->getSrcTy()->isIntegerTy(1)) - return SelectInst::Create(ZI->getOperand(0), SubOne(C), C); - // C-(X+C2) --> (C-C2)-X ConstantInt *C2; if (match(Op1, m_Add(m_Value(X), m_ConstantInt(C2)))) |