diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index b0e017571f6..c00f89267fb 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -2966,8 +2966,11 @@ SDValue DAGCombiner::visitADDCARRYLike(SDValue N0, SDValue N1, SDValue CarryIn, SDNode *N) { // Iff the flag result is dead: // (addcarry (add|uaddo X, Y), 0, Carry) -> (addcarry X, Y, Carry) + // Don't do this if the Carry comes from the uaddo. It won't remove the uaddo + // or the dependency between the instructions. if ((N0.getOpcode() == ISD::ADD || - (N0.getOpcode() == ISD::UADDO && N0.getResNo() == 0)) && + (N0.getOpcode() == ISD::UADDO && N0.getResNo() == 0 && + N0.getValue(1) != CarryIn)) && isNullConstant(N1) && !N->hasAnyUseOfValue(1)) return DAG.getNode(ISD::ADDCARRY, SDLoc(N), N->getVTList(), N0.getOperand(0), N0.getOperand(1), CarryIn); |
