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[InstCombine] use 'match' to reduce code; NFCI

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The later uses of dyn_castNotVal in this block are either
incomplete (doesn't handle vector constants) or overstepping
(shouldn't handle constants at all), but this first use is
just unnecessary. 'I' is obviously not a constant, and it 
can't be a not-of-a-not because that would already be
instsimplified.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301088 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Sanjay Patel 2017-04-22 18:05:35 +00:00
parent bb7651ba99
commit 56bf04cfa4
1 changed files with 32 additions and 37 deletions
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69
lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
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@ -2399,44 +2399,39 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
if (Value *V = SimplifyBSwap(I))
return replaceInstUsesWith(I, V);
// Is this a ~ operation?
if (Value *NotOp = dyn_castNotVal(&I)) {
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(NotOp)) {
if (Op0I->getOpcode() == Instruction::And ||
Op0I->getOpcode() == Instruction::Or) {
// ~(~X & Y) --> (X | ~Y) - De Morgan's Law
// ~(~X | Y) === (X & ~Y) - De Morgan's Law
if (dyn_castNotVal(Op0I->getOperand(1)))
Op0I->swapOperands();
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0))) {
Value *NotY =
Builder->CreateNot(Op0I->getOperand(1),
Op0I->getOperand(1)->getName()+".not");
if (Op0I->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(Op0NotVal, NotY);
return BinaryOperator::CreateAnd(Op0NotVal, NotY);
}
// ~(X & Y) --> (~X | ~Y) - De Morgan's Law
// ~(X | Y) === (~X & ~Y) - De Morgan's Law
if (IsFreeToInvert(Op0I->getOperand(0),
Op0I->getOperand(0)->hasOneUse()) &&
IsFreeToInvert(Op0I->getOperand(1),
Op0I->getOperand(1)->hasOneUse())) {
Value *NotX =
Builder->CreateNot(Op0I->getOperand(0), "notlhs");
Value *NotY =
Builder->CreateNot(Op0I->getOperand(1), "notrhs");
if (Op0I->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(NotX, NotY);
return BinaryOperator::CreateAnd(NotX, NotY);
}
} else if (Op0I->getOpcode() == Instruction::AShr) {
// ~(~X >>s Y) --> (X >>s Y)
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0)))
return BinaryOperator::CreateAShr(Op0NotVal, Op0I->getOperand(1));
// Is this a 'not' (~) fed by a binary operator?
BinaryOperator *NotOp;
if (match(&I, m_Not(m_BinOp(NotOp)))) {
if (NotOp->getOpcode() == Instruction::And ||
NotOp->getOpcode() == Instruction::Or) {
// ~(~X & Y) --> (X | ~Y) - De Morgan's Law
// ~(~X | Y) === (X & ~Y) - De Morgan's Law
if (dyn_castNotVal(NotOp->getOperand(1)))
NotOp->swapOperands();
if (Value *Op0NotVal = dyn_castNotVal(NotOp->getOperand(0))) {
Value *NotY = Builder->CreateNot(
NotOp->getOperand(1), NotOp->getOperand(1)->getName() + ".not");
if (NotOp->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(Op0NotVal, NotY);
return BinaryOperator::CreateAnd(Op0NotVal, NotY);
}
// ~(X & Y) --> (~X | ~Y) - De Morgan's Law
// ~(X | Y) === (~X & ~Y) - De Morgan's Law
if (IsFreeToInvert(NotOp->getOperand(0),
NotOp->getOperand(0)->hasOneUse()) &&
IsFreeToInvert(NotOp->getOperand(1),
NotOp->getOperand(1)->hasOneUse())) {
Value *NotX = Builder->CreateNot(NotOp->getOperand(0), "notlhs");
Value *NotY = Builder->CreateNot(NotOp->getOperand(1), "notrhs");
if (NotOp->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(NotX, NotY);
return BinaryOperator::CreateAnd(NotX, NotY);
}
} else if (NotOp->getOpcode() == Instruction::AShr) {
// ~(~X >>s Y) --> (X >>s Y)
if (Value *Op0NotVal = dyn_castNotVal(NotOp->getOperand(0)))
return BinaryOperator::CreateAShr(Op0NotVal, NotOp->getOperand(1));
}
}