maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[TargetLowering] Move the setBooleanContents check on (xor (setcc), (setcc)) == / != 1 -> (setcc) != / == (setcc) to the right place 

We need to be checking the value types for the inner setccs not
the outer setcc. We need to ensure those setccs produce a 0/1
value or that the xor is on the i1 type. I think at the time
this code was originally written, getBooleanContents didn't
take any arguments so this was probably correct. But now we can
have a different boolean contents for integer and floating point.

Not sure why the other combines below the xor were also checking
the boolean contents. None of them involve any setccs other than
the outer one and they only produce a new setcc.

Differential Revision: https://reviews.llvm.org/D69480
This commit is contained in:
Craig Topper 2019-11-01 14:09:08 -07:00
parent 42d77461f3
commit 96bb076621
1 changed files with 13 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
View File

@ -3423,10 +3423,7 @@ SDValue TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1,
return DAG.getSetCC(dl, VT, Val, N1,
Cond == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ);
}
} else if (N1C->isOne() &&
(VT == MVT::i1 ||
getBooleanContents(N0.getValueType()) ==
ZeroOrOneBooleanContent)) {
} else if (N1C->isOne()) {
SDValue Op0 = N0;
if (Op0.getOpcode() == ISD::TRUNCATE)
Op0 = Op0.getOperand(0);
@ -3434,10 +3431,18 @@ SDValue TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1,
if ((Op0.getOpcode() == ISD::XOR) &&
Op0.getOperand(0).getOpcode() == ISD::SETCC &&
Op0.getOperand(1).getOpcode() == ISD::SETCC) {
// (xor (setcc), (setcc)) == / != 1 -> (setcc) != / == (setcc)
Cond = (Cond == ISD::SETEQ) ? ISD::SETNE : ISD::SETEQ;
return DAG.getSetCC(dl, VT, Op0.getOperand(0), Op0.getOperand(1),
Cond);
SDValue XorLHS = Op0.getOperand(0);
SDValue XorRHS = Op0.getOperand(1);
// Ensure that the input setccs return an i1 type or 0/1 value.
if (Op0.getValueType() == MVT::i1 ||
(getBooleanContents(XorLHS.getOperand(0).getValueType()) ==
ZeroOrOneBooleanContent &&
getBooleanContents(XorRHS.getOperand(0).getValueType()) ==
ZeroOrOneBooleanContent)) {
// (xor (setcc), (setcc)) == / != 1 -> (setcc) != / == (setcc)
Cond = (Cond == ISD::SETEQ) ? ISD::SETNE : ISD::SETEQ;
return DAG.getSetCC(dl, VT, XorLHS, XorRHS, Cond);
}
}
if (Op0.getOpcode() == ISD::AND &&
isa<ConstantSDNode>(Op0.getOperand(1)) &&