diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index e61cb0c1e5a..59197baeb0c 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -6431,7 +6431,6 @@ void SelectionDAGLegalize::ExpandOp(SDValue Op, SDValue &Lo, SDValue &Hi){ break; } } - // Expand the subcomponents. SDValue LHSL, LHSH, RHSL, RHSH; ExpandOp(Node->getOperand(0), LHSL, LHSH); @@ -6442,16 +6441,41 @@ void SelectionDAGLegalize::ExpandOp(SDValue Op, SDValue &Lo, SDValue &Hi){ LoOps[1] = RHSL; HiOps[0] = LHSH; HiOps[1] = RHSH; - if (Node->getOpcode() == ISD::ADD) { - Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2); - HiOps[2] = Lo.getValue(1); - Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3); + if(TLI.isOperationLegal(ISD::ADDC, NVT)) { + if (Node->getOpcode() == ISD::ADD) { + Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2); + HiOps[2] = Lo.getValue(1); + Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3); + } else { + Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2); + HiOps[2] = Lo.getValue(1); + Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3); + } + break; } else { - Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2); - HiOps[2] = Lo.getValue(1); - Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3); + 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 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 Carry2 = DAG.getNode(ISD::SELECT, NVT, Cmp2, + DAG.getConstant(1, NVT), + Carry1); + Hi = DAG.getNode(ISD::ADD, NVT, Hi, Carry2); + } else { + Lo = DAG.getNode(ISD::SUB, VTList, LoOps, 2); + Hi = DAG.getNode(ISD::SUB, VTList, HiOps, 2); + SDValue Cmp = DAG.getSetCC(NVT, LoOps[0], LoOps[1], ISD::SETULT); + SDValue Borrow = DAG.getNode(ISD::SELECT, NVT, Cmp, + DAG.getConstant(1, NVT), + DAG.getConstant(0, NVT)); + Hi = DAG.getNode(ISD::SUB, NVT, Hi, Borrow); + } + break; } - break; } case ISD::ADDC: diff --git a/test/CodeGen/Alpha/add128.ll b/test/CodeGen/Alpha/add128.ll index 6432b2d9a84..61d020890e8 100644 --- a/test/CodeGen/Alpha/add128.ll +++ b/test/CodeGen/Alpha/add128.ll @@ -1,7 +1,6 @@ ;test for ADDC and ADDE expansion ; ; RUN: llvm-as < %s | llc -march=alpha -; XFAIL: * define i128 @add128(i128 %x, i128 %y) { entry: diff --git a/test/CodeGen/Alpha/sub128.ll b/test/CodeGen/Alpha/sub128.ll new file mode 100644 index 00000000000..cb18559e532 --- /dev/null +++ b/test/CodeGen/Alpha/sub128.ll @@ -0,0 +1,9 @@ +;test for SUBC and SUBE expansion +; +; RUN: llvm-as < %s | llc -march=alpha + +define i128 @sub128(i128 %x, i128 %y) { +entry: + %tmp = sub i128 %y, %x + ret i128 %tmp +}