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[InstCombine] Remove explicit code for folding (xor(zext(cmp)), 1) and (xor(sext(cmp)), -1) to ext(!cmp). 

As far as I can tell this should be handled by foldCastedBitwiseLogic which is called later in visitXor.

Differential Revision: https://reviews.llvm.org/D36214

llvm-svn: 309882
This commit is contained in:
Craig Topper 2017-08-02 20:30:27 +00:00
parent c9da8f0f64
commit 4068e4eec5
1 changed files with 0 additions and 15 deletions
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15
llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
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@ -2439,21 +2439,6 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
}
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(Op1)) {
// fold (xor(zext(cmp)), 1) and (xor(sext(cmp)), -1) to ext(!cmp).
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
if (CmpInst *CI = dyn_cast<CmpInst>(Op0C->getOperand(0))) {
if (CI->hasOneUse() && Op0C->hasOneUse()) {
Instruction::CastOps Opcode = Op0C->getOpcode();
if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
(RHSC == ConstantExpr::getCast(Opcode, Builder.getTrue(),
Op0C->getDestTy()))) {
CI->setPredicate(CI->getInversePredicate());
return CastInst::Create(Opcode, CI, Op0C->getType());
}
}
}
}
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
// ~(c-X) == X-c-1 == X+(-c-1)
if (Op0I->getOpcode() == Instruction::Sub && RHSC->isMinusOne())