diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 42d163f79b..d4d13884cb 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -924,9 +924,14 @@ SDValue DAGCombiner::visitTokenFactor(SDNode *N) { /// MERGE_VALUES can always be eliminated. SDValue DAGCombiner::visitMERGE_VALUES(SDNode *N) { WorkListRemover DeadNodes(*this); - for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) - DAG.ReplaceAllUsesOfValueWith(SDValue(N, i), N->getOperand(i), - &DeadNodes); + // Replacing results may cause a different MERGE_VALUES to suddenly + // be CSE'd with N, and carry its uses with it. Iterate until no + // uses remain, to ensure that the node can be safely deleted. + do { + for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) + DAG.ReplaceAllUsesOfValueWith(SDValue(N, i), N->getOperand(i), + &DeadNodes); + } while (!N->use_empty()); removeFromWorkList(N); DAG.DeleteNode(N); return SDValue(N, 0); // Return N so it doesn't get rechecked! |