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Differential D4253 Diff 10881 llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp

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llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp

Show First 20 Lines • Show All 1,125 Lines • ▼ Show 20 Lines if (LHSKnownZero != 0) {
computeKnownBits(RHS, RHSKnownZero, RHSKnownOne); computeKnownBits(RHS, RHSKnownZero, RHSKnownOne);
// No bits in common -> bitwise or. // No bits in common -> bitwise or.
if ((LHSKnownZero|RHSKnownZero).isAllOnesValue()) if ((LHSKnownZero|RHSKnownZero).isAllOnesValue())
return BinaryOperator::CreateOr(LHS, RHS); return BinaryOperator::CreateOr(LHS, RHS);
} }
} }
// W*X + Y*Z --> W * (X+Z) iff W == Y
{
Value *W, *X, *Y, *Z;
if (match(LHS, m_Mul(m_Value(W), m_Value(X))) &&
match(RHS, m_Mul(m_Value(Y), m_Value(Z)))) {
if (W != Y) {
if (W == Z) {
std::swap(Y, Z);
} else if (Y == X) {
std::swap(W, X);
} else if (X == Z) {
std::swap(Y, Z);
std::swap(W, X);
}
}
if (W == Y) {
Value *NewAdd = Builder->CreateAdd(X, Z, LHS->getName());
return BinaryOperator::CreateMul(W, NewAdd);
}
}
}
if (Constant *CRHS = dyn_cast<Constant>(RHS)) { if (Constant *CRHS = dyn_cast<Constant>(RHS)) {
Value *X; Value *X;
if (match(LHS, m_Not(m_Value(X)))) // ~X + C --> (C-1) - X if (match(LHS, m_Not(m_Value(X)))) // ~X + C --> (C-1) - X
return BinaryOperator::CreateSub(SubOne(CRHS), X); return BinaryOperator::CreateSub(SubOne(CRHS), X);
} }
if (ConstantInt *CRHS = dyn_cast<ConstantInt>(RHS)) { if (ConstantInt *CRHS = dyn_cast<ConstantInt>(RHS)) {
// (X & FF00) + xx00 -> (X+xx00) & FF00 // (X & FF00) + xx00 -> (X+xx00) & FF00
▲ Show 20 Lines • Show All 402 Lines • ▼ Show 20 Lines if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) &&
match(Op0, m_Zero())) match(Op0, m_Zero()))
return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C)); return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C));
// 0 - (X << Y) -> (-X << Y) when X is freely negatable. // 0 - (X << Y) -> (-X << Y) when X is freely negatable.
if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero())) if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero()))
if (Value *XNeg = dyn_castNegVal(X)) if (Value *XNeg = dyn_castNegVal(X))
return BinaryOperator::CreateShl(XNeg, Y); return BinaryOperator::CreateShl(XNeg, Y);
// X - X*C --> X * (1-C)
if (match(Op1, m_Mul(m_Specific(Op0), m_Constant(CI)))) {
Constant *CP1 = ConstantExpr::getSub(ConstantInt::get(I.getType(),1), CI);
return BinaryOperator::CreateMul(Op0, CP1);
}
// X - X<<C --> X * (1-(1<<C))
if (match(Op1, m_Shl(m_Specific(Op0), m_Constant(CI)))) {
Constant *One = ConstantInt::get(I.getType(), 1);
C = ConstantExpr::getSub(One, ConstantExpr::getShl(One, CI));
return BinaryOperator::CreateMul(Op0, C);
}
// X - A*-B -> X + A*B // X - A*-B -> X + A*B
// X - -A*B -> X + A*B // X - -A*B -> X + A*B
Value *A, *B; Value *A, *B;
if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) || if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B)))) match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B))))
return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B)); return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B));
// X - A*CI -> X + A*-CI // X - A*CI -> X + A*-CI
▲ Show 20 Lines • Show All 71 Lines • Show Last 20 Lines