replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Fold setcc of MVT::i1 operands into logical operations 

llvm-svn: 21319
This commit is contained in:
Chris Lattner 2005-04-18 04:48:12 +00:00
parent 6d40fd01fe
commit b61ecb5875
1 changed files with 39 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
View File

@ -597,6 +597,45 @@ SDOperand SelectionDAG::getSetCC(ISD::CondCode Cond, MVT::ValueType VT,
}
}
// Fold away ALL boolean setcc's.
if (N1.getValueType() == MVT::i1) {
switch (Cond) {
default: assert(0 && "Unknown integer setcc!");
case ISD::SETEQ: // X == Y -> (X^Y)^1
N1 = getNode(ISD::XOR, MVT::i1,
getNode(ISD::XOR, MVT::i1, N1, N2),
getConstant(1, MVT::i1));
break;
case ISD::SETNE: // X != Y --> (X^Y)
N1 = getNode(ISD::XOR, MVT::i1, N1, N2);
break;
case ISD::SETGT: // X >s Y --> X == 0 & Y == 1 --> X^1 & Y
case ISD::SETULT: // X <u Y --> X == 0 & Y == 1 --> X^1 & Y
N1 = getNode(ISD::AND, MVT::i1, N2,
getNode(ISD::XOR, MVT::i1, N1, getConstant(1, MVT::i1)));
break;
case ISD::SETLT: // X <s Y --> X == 1 & Y == 0 --> Y^1 & X
case ISD::SETUGT: // X >u Y --> X == 1 & Y == 0 --> Y^1 & X
N1 = getNode(ISD::AND, MVT::i1, N1,
getNode(ISD::XOR, MVT::i1, N2, getConstant(1, MVT::i1)));
break;
case ISD::SETULE: // X <=u Y --> X == 0 | Y == 1 --> X^1 | Y
case ISD::SETGE: // X >=s Y --> X == 0 | Y == 1 --> X^1 | Y
N1 = getNode(ISD::OR, MVT::i1, N2,
getNode(ISD::XOR, MVT::i1, N1, getConstant(1, MVT::i1)));
break;
case ISD::SETUGE: // X >=u Y --> X == 1 | Y == 0 --> Y^1 | X
case ISD::SETLE: // X <=s Y --> X == 1 | Y == 0 --> Y^1 | X
N1 = getNode(ISD::OR, MVT::i1, N1,
getNode(ISD::XOR, MVT::i1, N2, getConstant(1, MVT::i1)));
break;
}
if (VT != MVT::i1)
N1 = getNode(ISD::ZERO_EXTEND, VT, N1);
return N1;
}
SetCCSDNode *&N = SetCCs[std::make_pair(std::make_pair(N1, N2),
std::make_pair(Cond, VT))];
if (N) return SDOperand(N, 0);