Don't rely on doubles comparing identical to each other, which doesn't work

for 0.0 and -0.0.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20230 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-02-17 20:17:32 +00:00
parent b29cb29364
commit d8658616cf

View File

@ -196,10 +196,15 @@ void SelectionDAG::DeleteNodeIfDead(SDNode *N, void *NodeSet) {
Constants.erase(std::make_pair(cast<ConstantSDNode>(N)->getValue(),
N->getValueType(0)));
break;
case ISD::ConstantFP:
ConstantFPs.erase(std::make_pair(cast<ConstantFPSDNode>(N)->getValue(),
N->getValueType(0)));
case ISD::ConstantFP: {
union {
double DV;
uint64_t IV;
};
DV = cast<ConstantFPSDNode>(N)->getValue();
ConstantFPs.erase(std::make_pair(IV, N->getValueType(0)));
break;
}
case ISD::GlobalAddress:
GlobalValues.erase(cast<GlobalAddressSDNode>(N)->getGlobal());
break;
@ -299,7 +304,17 @@ SDOperand SelectionDAG::getConstantFP(double Val, MVT::ValueType VT) {
if (VT == MVT::f32)
Val = (float)Val; // Mask out extra precision.
SDNode *&N = ConstantFPs[std::make_pair(Val, VT)];
// Do the map lookup using the actual bit pattern for the floating point
// value, so that we don't have problems with 0.0 comparing equal to -0.0, and
// we don't have issues with SNANs.
union {
double DV;
uint64_t IV;
};
DV = Val;
SDNode *&N = ConstantFPs[std::make_pair(IV, VT)];
if (N) return SDOperand(N, 0);
N = new ConstantFPSDNode(Val, VT);
AllNodes.push_back(N);