mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-19 02:52:53 +02:00
A bunch of cleanups and simplifications using the new PatternMatch predicates
and generally tidying things up. Only very trivial functionality changes like now doing (-1 - A) -> (~A) for vectors too. InstCombineAddSub.cpp | 296 +++++++++++++++++++++----------------------------- 1 file changed, 126 insertions(+), 170 deletions(-) llvm-svn: 125264
This commit is contained in:
Chris Lattner
parent
c741c5d744
commit
b974ff0c57
@ -95,35 +95,26 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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if (Value *V = SimplifyUsingDistributiveLaws(I))
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return ReplaceInstUsesWith(I, V);
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if (Constant *RHSC = dyn_cast<Constant>(RHS)) {
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if (ConstantInt *CI = dyn_cast<ConstantInt>(RHSC)) {
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// X + (signbit) --> X ^ signbit
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const APInt& Val = CI->getValue();
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uint32_t BitWidth = Val.getBitWidth();
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if (Val == APInt::getSignBit(BitWidth))
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return BinaryOperator::CreateXor(LHS, RHS);
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// See if SimplifyDemandedBits can simplify this. This handles stuff like
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// (X & 254)+1 -> (X&254)|1
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if (SimplifyDemandedInstructionBits(I))
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return &I;
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// zext(bool) + C -> bool ? C + 1 : C
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if (ZExtInst *ZI = dyn_cast<ZExtInst>(LHS))
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if (ZI->getSrcTy() == Type::getInt1Ty(I.getContext()))
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return SelectInst::Create(ZI->getOperand(0), AddOne(CI), CI);
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}
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if (isa<PHINode>(LHS))
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if (Instruction *NV = FoldOpIntoPhi(I))
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return NV;
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if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
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// X + (signbit) --> X ^ signbit
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const APInt &Val = CI->getValue();
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if (Val.isSignBit())
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return BinaryOperator::CreateXor(LHS, RHS);
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ConstantInt *XorRHS = 0;
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Value *XorLHS = 0;
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if (isa<ConstantInt>(RHSC) &&
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match(LHS, m_Xor(m_Value(XorLHS), m_ConstantInt(XorRHS)))) {
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// See if SimplifyDemandedBits can simplify this. This handles stuff like
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// (X & 254)+1 -> (X&254)|1
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if (SimplifyDemandedInstructionBits(I))
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return &I;
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// zext(bool) + C -> bool ? C + 1 : C
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if (ZExtInst *ZI = dyn_cast<ZExtInst>(LHS))
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if (ZI->getSrcTy()->isIntegerTy(1))
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return SelectInst::Create(ZI->getOperand(0), AddOne(CI), CI);
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Value *XorLHS = 0; ConstantInt *XorRHS = 0;
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if (match(LHS, m_Xor(m_Value(XorLHS), m_ConstantInt(XorRHS)))) {
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uint32_t TySizeBits = I.getType()->getScalarSizeInBits();
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const APInt& RHSVal = cast<ConstantInt>(RHSC)->getValue();
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const APInt &RHSVal = CI->getValue();
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unsigned ExtendAmt = 0;
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// If we have ADD(XOR(AND(X, 0xFF), 0x80), 0xF..F80), it's a sext.
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// If we have ADD(XOR(AND(X, 0xFF), 0xF..F80), 0x80), it's a sext.
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@ -133,13 +124,13 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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else if (XorRHS->getValue().isPowerOf2())
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ExtendAmt = TySizeBits - XorRHS->getValue().logBase2() - 1;
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}
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if (ExtendAmt) {
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APInt Mask = APInt::getHighBitsSet(TySizeBits, ExtendAmt);
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if (!MaskedValueIsZero(XorLHS, Mask))
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ExtendAmt = 0;
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}
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if (ExtendAmt) {
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Constant *ShAmt = ConstantInt::get(I.getType(), ExtendAmt);
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Value *NewShl = Builder->CreateShl(XorLHS, ShAmt, "sext");
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@ -148,23 +139,23 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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}
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}
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if (isa<Constant>(RHS) && isa<PHINode>(LHS))
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if (Instruction *NV = FoldOpIntoPhi(I))
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return NV;
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if (I.getType()->isIntegerTy(1))
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return BinaryOperator::CreateXor(LHS, RHS);
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if (I.getType()->isIntegerTy()) {
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// X + X --> X << 1
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if (LHS == RHS)
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return BinaryOperator::CreateShl(LHS, ConstantInt::get(I.getType(), 1));
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}
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// X + X --> X << 1
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if (LHS == RHS && I.getType()->isIntegerTy())
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return BinaryOperator::CreateShl(LHS, ConstantInt::get(I.getType(), 1));
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// -A + B --> B - A
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// -A + -B --> -(A + B)
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if (Value *LHSV = dyn_castNegVal(LHS)) {
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if (LHS->getType()->isIntOrIntVectorTy()) {
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if (Value *RHSV = dyn_castNegVal(RHS)) {
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Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum");
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return BinaryOperator::CreateNeg(NewAdd);
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}
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if (Value *RHSV = dyn_castNegVal(RHS)) {
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Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum");
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return BinaryOperator::CreateNeg(NewAdd);
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}
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return BinaryOperator::CreateSub(RHS, LHSV);
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@ -209,7 +200,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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}
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// W*X + Y*Z --> W * (X+Z) iff W == Y
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if (I.getType()->isIntOrIntVectorTy()) {
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{
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Value *W, *X, *Y, *Z;
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if (match(LHS, m_Mul(m_Value(W), m_Value(X))) &&
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match(RHS, m_Mul(m_Value(Y), m_Value(Z)))) {
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@ -238,24 +229,22 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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// (X & FF00) + xx00 -> (X+xx00) & FF00
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if (LHS->hasOneUse() &&
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match(LHS, m_And(m_Value(X), m_ConstantInt(C2)))) {
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Constant *Anded = ConstantExpr::getAnd(CRHS, C2);
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if (Anded == CRHS) {
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// See if all bits from the first bit set in the Add RHS up are included
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// in the mask. First, get the rightmost bit.
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const APInt &AddRHSV = CRHS->getValue();
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match(LHS, m_And(m_Value(X), m_ConstantInt(C2))) &&
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CRHS->getValue() == (CRHS->getValue() & C2->getValue())) {
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// See if all bits from the first bit set in the Add RHS up are included
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// in the mask. First, get the rightmost bit.
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const APInt &AddRHSV = CRHS->getValue();
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// Form a mask of all bits from the lowest bit added through the top.
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APInt AddRHSHighBits(~((AddRHSV & -AddRHSV)-1));
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// Form a mask of all bits from the lowest bit added through the top.
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APInt AddRHSHighBits(~((AddRHSV & -AddRHSV)-1));
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// See if the and mask includes all of these bits.
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APInt AddRHSHighBitsAnd(AddRHSHighBits & C2->getValue());
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// See if the and mask includes all of these bits.
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APInt AddRHSHighBitsAnd(AddRHSHighBits & C2->getValue());
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if (AddRHSHighBits == AddRHSHighBitsAnd) {
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// Okay, the xform is safe. Insert the new add pronto.
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Value *NewAdd = Builder->CreateAdd(X, CRHS, LHS->getName());
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return BinaryOperator::CreateAnd(NewAdd, C2);
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}
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if (AddRHSHighBits == AddRHSHighBitsAnd) {
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// Okay, the xform is safe. Insert the new add pronto.
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Value *NewAdd = Builder->CreateAdd(X, CRHS, LHS->getName());
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return BinaryOperator::CreateAnd(NewAdd, C2);
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}
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}
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@ -280,12 +269,11 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
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// Can we fold the add into the argument of the select?
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// We check both true and false select arguments for a matching subtract.
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if (match(FV, m_Zero()) &&
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match(TV, m_Sub(m_Value(N), m_Specific(A))))
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if (match(FV, m_Zero()) && match(TV, m_Sub(m_Value(N), m_Specific(A))))
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// Fold the add into the true select value.
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return SelectInst::Create(SI->getCondition(), N, A);
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if (match(TV, m_Zero()) &&
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match(FV, m_Sub(m_Value(N), m_Specific(A))))
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if (match(TV, m_Zero()) && match(FV, m_Sub(m_Value(N), m_Specific(A))))
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// Fold the add into the false select value.
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return SelectInst::Create(SI->getCondition(), A, N);
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}
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@ -550,12 +538,12 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
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if (I.getType()->isIntegerTy(1))
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return BinaryOperator::CreateXor(Op0, Op1);
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// Replace (-1 - A) with (~A).
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if (match(Op0, m_AllOnes()))
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return BinaryOperator::CreateNot(Op1);
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if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
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// Replace (-1 - A) with (~A).
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if (C->isAllOnesValue())
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return BinaryOperator::CreateNot(Op1);
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// C - ~X == X + (1+C)
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Value *X = 0;
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if (match(Op1, m_Not(m_Value(X))))
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@ -564,29 +552,16 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
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// -(X >>u 31) -> (X >>s 31)
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// -(X >>s 31) -> (X >>u 31)
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if (C->isZero()) {
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if (BinaryOperator *SI = dyn_cast<BinaryOperator>(Op1)) {
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if (SI->getOpcode() == Instruction::LShr) {
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if (ConstantInt *CU = dyn_cast<ConstantInt>(SI->getOperand(1))) {
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// Check to see if we are shifting out everything but the sign bit.
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if (CU->getLimitedValue(SI->getType()->getPrimitiveSizeInBits()) ==
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SI->getType()->getPrimitiveSizeInBits()-1) {
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// Ok, the transformation is safe. Insert AShr.
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return BinaryOperator::Create(Instruction::AShr,
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SI->getOperand(0), CU, SI->getName());
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}
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}
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} else if (SI->getOpcode() == Instruction::AShr) {
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if (ConstantInt *CU = dyn_cast<ConstantInt>(SI->getOperand(1))) {
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// Check to see if we are shifting out everything but the sign bit.
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if (CU->getLimitedValue(SI->getType()->getPrimitiveSizeInBits()) ==
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SI->getType()->getPrimitiveSizeInBits()-1) {
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// Ok, the transformation is safe. Insert LShr.
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return BinaryOperator::CreateLShr(
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SI->getOperand(0), CU, SI->getName());
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}
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}
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}
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}
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Value *X; ConstantInt *CI;
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if (match(Op1, m_LShr(m_Value(X), m_ConstantInt(CI))) &&
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// Verify we are shifting out everything but the sign bit.
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CI->getValue() == I.getType()->getPrimitiveSizeInBits()-1)
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return BinaryOperator::CreateAShr(X, CI);
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if (match(Op1, m_AShr(m_Value(X), m_ConstantInt(CI))) &&
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// Verify we are shifting out everything but the sign bit.
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CI->getValue() == I.getType()->getPrimitiveSizeInBits()-1)
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return BinaryOperator::CreateLShr(X, CI);
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}
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// Try to fold constant sub into select arguments.
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@ -596,99 +571,80 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
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// C - zext(bool) -> bool ? C - 1 : C
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if (ZExtInst *ZI = dyn_cast<ZExtInst>(Op1))
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if (ZI->getSrcTy() == Type::getInt1Ty(I.getContext()))
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if (ZI->getSrcTy()->isIntegerTy(1))
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return SelectInst::Create(ZI->getOperand(0), SubOne(C), C);
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// C-(X+C2) --> (C-C2)-X
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ConstantInt *C2;
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if (match(Op1, m_Add(m_Value(X), m_ConstantInt(C2))))
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return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
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}
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if (BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1)) {
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if (Op1I->getOpcode() == Instruction::Add) {
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if (Op1I->getOperand(0) == Op0) // X-(X+Y) == -Y
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return BinaryOperator::CreateNeg(Op1I->getOperand(1),
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I.getName());
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else if (Op1I->getOperand(1) == Op0) // X-(Y+X) == -Y
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return BinaryOperator::CreateNeg(Op1I->getOperand(0),
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I.getName());
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else if (ConstantInt *CI1 = dyn_cast<ConstantInt>(I.getOperand(0))) {
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if (ConstantInt *CI2 = dyn_cast<ConstantInt>(Op1I->getOperand(1)))
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// C1-(X+C2) --> (C1-C2)-X
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return BinaryOperator::CreateSub(
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ConstantExpr::getSub(CI1, CI2), Op1I->getOperand(0));
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}
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{ Value *Y;
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// X-(X+Y) == -Y X-(Y+X) == -Y
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if (match(Op1, m_Add(m_Specific(Op0), m_Value(Y))) ||
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match(Op1, m_Add(m_Value(Y), m_Specific(Op0))))
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return BinaryOperator::CreateNeg(Y);
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// (X-Y)-X == -Y
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if (match(Op0, m_Sub(m_Specific(Op1), m_Value(Y))))
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return BinaryOperator::CreateNeg(Y);
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}
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if (Op1->hasOneUse()) {
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Value *X = 0, *Y = 0, *Z = 0;
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Constant *C = 0;
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ConstantInt *CI = 0;
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// (X - (Y - Z)) --> (X + (Z - Y)).
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if (match(Op1, m_Sub(m_Value(Y), m_Value(Z))))
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return BinaryOperator::CreateAdd(Op0,
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Builder->CreateSub(Z, Y, Op1->getName()));
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// (X - (X & Y)) --> (X & ~Y)
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//
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if (match(Op1, m_And(m_Value(Y), m_Specific(Op0))) ||
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match(Op1, m_And(m_Specific(Op0), m_Value(Y))))
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return BinaryOperator::CreateAnd(Op0,
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Builder->CreateNot(Y, Y->getName() + ".not"));
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// 0 - (X sdiv C) -> (X sdiv -C)
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if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) &&
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match(Op0, m_Zero()))
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return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C));
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// 0 - (X << Y) -> (-X << Y) when X is freely negatable.
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if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero()))
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if (Value *XNeg = dyn_castNegVal(X))
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return BinaryOperator::CreateShl(XNeg, Y);
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// X - X*C --> X * (1-C)
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if (match(Op1, m_Mul(m_Specific(Op0), m_ConstantInt(CI)))) {
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Constant *CP1 = ConstantExpr::getSub(ConstantInt::get(I.getType(),1), CI);
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return BinaryOperator::CreateMul(Op0, CP1);
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}
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if (Op1I->hasOneUse()) {
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// Replace (x - (y - z)) with (x + (z - y)) if the (y - z) subexpression
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// is not used by anyone else...
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//
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if (Op1I->getOpcode() == Instruction::Sub) {
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// Swap the two operands of the subexpr...
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Value *IIOp0 = Op1I->getOperand(0), *IIOp1 = Op1I->getOperand(1);
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Op1I->setOperand(0, IIOp1);
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Op1I->setOperand(1, IIOp0);
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// Create the new top level add instruction...
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return BinaryOperator::CreateAdd(Op0, Op1);
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}
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// Replace (A - (A & B)) with (A & ~B) if this is the only use of (A&B)...
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//
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if (Op1I->getOpcode() == Instruction::And &&
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(Op1I->getOperand(0) == Op0 || Op1I->getOperand(1) == Op0)) {
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Value *OtherOp = Op1I->getOperand(Op1I->getOperand(0) == Op0);
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Value *NewNot = Builder->CreateNot(OtherOp, "B.not");
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return BinaryOperator::CreateAnd(Op0, NewNot);
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}
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// 0 - (X sdiv C) -> (X sdiv -C)
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if (Op1I->getOpcode() == Instruction::SDiv)
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if (ConstantInt *CSI = dyn_cast<ConstantInt>(Op0))
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if (CSI->isZero())
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if (Constant *DivRHS = dyn_cast<Constant>(Op1I->getOperand(1)))
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return BinaryOperator::CreateSDiv(Op1I->getOperand(0),
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ConstantExpr::getNeg(DivRHS));
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// 0 - (C << X) -> (-C << X)
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if (Op1I->getOpcode() == Instruction::Shl)
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if (ConstantInt *CSI = dyn_cast<ConstantInt>(Op0))
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if (CSI->isZero())
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if (Value *ShlLHSNeg = dyn_castNegVal(Op1I->getOperand(0)))
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return BinaryOperator::CreateShl(ShlLHSNeg, Op1I->getOperand(1));
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// X - X*C --> X * (1-C)
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ConstantInt *C2 = 0;
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if (dyn_castFoldableMul(Op1I, C2) == Op0) {
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Constant *CP1 =
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ConstantExpr::getSub(ConstantInt::get(I.getType(), 1),
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C2);
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return BinaryOperator::CreateMul(Op0, CP1);
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}
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// X - A*-B -> X + A*B
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// X - -A*B -> X + A*B
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Value *A, *B;
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if (match(Op1I, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
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match(Op1I, m_Mul(m_Neg(m_Value(A)), m_Value(B)))) {
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Value *NewMul = Builder->CreateMul(A, B);
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return BinaryOperator::CreateAdd(Op0, NewMul);
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}
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// X - X<<C --> X * (1-(1<<C))
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if (match(Op1, m_Shl(m_Specific(Op0), m_ConstantInt(CI)))) {
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Constant *One = ConstantInt::get(I.getType(), 1);
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C = ConstantExpr::getSub(One, ConstantExpr::getShl(One, CI));
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return BinaryOperator::CreateMul(Op0, C);
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}
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// X - A*-B -> X + A*B
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// X - -A*B -> X + A*B
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Value *A, *B;
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if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
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match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B))))
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return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B));
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// X - A*Cst -> X + A*-Cst
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// X - Cst*A -> X + A*-Cst
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ConstantInt *BCst;
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if (match(Op1I, m_Mul(m_Value(A), m_ConstantInt(BCst))) ||
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match(Op1I, m_Mul(m_ConstantInt(BCst), m_Value(A)))) {
|
||||
Value *NewMul = Builder->CreateMul(A, ConstantExpr::getNeg(BCst));
|
||||
return BinaryOperator::CreateAdd(Op0, NewMul);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
|
||||
if (Op0I->getOpcode() == Instruction::Sub) {
|
||||
if (Op0I->getOperand(0) == Op1) // (X-Y)-X == -Y
|
||||
return BinaryOperator::CreateNeg(Op0I->getOperand(1),
|
||||
I.getName());
|
||||
// X - A*CI -> X + A*-CI
|
||||
// X - CI*A -> X + A*-CI
|
||||
if (match(Op1, m_Mul(m_Value(A), m_ConstantInt(CI))) ||
|
||||
match(Op1, m_Mul(m_ConstantInt(CI), m_Value(A)))) {
|
||||
Value *NewMul = Builder->CreateMul(A, ConstantExpr::getNeg(CI));
|
||||
return BinaryOperator::CreateAdd(Op0, NewMul);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user