Use ADDC if it is valid at any smaller size. fixes test/Codegen/Generic/i128-addsub.ll on x86

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57247 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Lenharth 2008-10-07 17:03:15 +00:00
parent ae436cecca
commit 5c9cc1392c

View File

@ -6441,7 +6441,20 @@ void SelectionDAGLegalize::ExpandOp(SDValue Op, SDValue &Lo, SDValue &Hi){
LoOps[1] = RHSL;
HiOps[0] = LHSH;
HiOps[1] = RHSH;
if(TLI.isOperationLegal(ISD::ADDC, NVT)) {
//cascaded check to see if any smaller size has a a carry flag.
unsigned OpV = Node->getOpcode() == ISD::ADD ? ISD::ADDC : ISD::SUBC;
bool hasCarry = false;
if (NVT == MVT::i64)
hasCarry |= TLI.isOperationLegal(OpV, MVT::i32)
| TLI.isOperationLegal(OpV, MVT::i16)
| TLI.isOperationLegal(OpV, MVT::i8);
if (NVT == MVT::i32)
hasCarry |= TLI.isOperationLegal(OpV, MVT::i16)
| TLI.isOperationLegal(OpV, MVT::i8);
if (NVT == MVT::i16)
hasCarry |= TLI.isOperationLegal(OpV, MVT::i8);
if(hasCarry) {
if (Node->getOpcode() == ISD::ADD) {
Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
HiOps[2] = Lo.getValue(1);
@ -6456,11 +6469,13 @@ void SelectionDAGLegalize::ExpandOp(SDValue Op, SDValue &Lo, SDValue &Hi){
if (Node->getOpcode() == ISD::ADD) {
Lo = DAG.getNode(ISD::ADD, VTList, LoOps, 2);
Hi = DAG.getNode(ISD::ADD, VTList, HiOps, 2);
SDValue Cmp1 = DAG.getSetCC(NVT, Lo, LoOps[0], ISD::SETULT);
SDValue Cmp1 = DAG.getSetCC(TLI.getSetCCResultType(Lo),
Lo, LoOps[0], ISD::SETULT);
SDValue Carry1 = DAG.getNode(ISD::SELECT, NVT, Cmp1,
DAG.getConstant(1, NVT),
DAG.getConstant(0, NVT));
SDValue Cmp2 = DAG.getSetCC(NVT, Lo, LoOps[1], ISD::SETULT);
SDValue Cmp2 = DAG.getSetCC(TLI.getSetCCResultType(Lo),
Lo, LoOps[1], ISD::SETULT);
SDValue Carry2 = DAG.getNode(ISD::SELECT, NVT, Cmp2,
DAG.getConstant(1, NVT),
Carry1);