From 07bf5349eede1fb207a462d19743cc10135996ca Mon Sep 17 00:00:00 2001 From: Justin Bogner Date: Fri, 3 Jun 2016 20:47:40 +0000 Subject: Re-apply "SDAG: Update ChainNodesMatched as nodes are deleted" My first attempt at this had an overly aggressive assert - chain nodes will only be removed, but we could hit the assert if a non-chain node was CSE'd (NodeToMatch, for instance). This reapplies r271706 by reverting r271713 and fixing an assert. Original message: Avoid relying on UB by looking into deleted nodes for a marker value. Instead, update the list of chain nodes as we go. llvm-svn: 271733 --- llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index 359919e14b2..0ae1a95b875 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -2163,10 +2163,8 @@ void SelectionDAGISel::UpdateChains( // Replace all the chain results with the final chain we ended up with. for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) { SDNode *ChainNode = ChainNodesMatched[i]; - - // If this node was already deleted, don't look at it. - if (ChainNode->getOpcode() == ISD::DELETED_NODE) - continue; + assert(ChainNode->getOpcode() != ISD::DELETED_NODE && + "Deleted node left in chain"); // Don't replace the results of the root node if we're doing a // MorphNodeTo. @@ -3368,6 +3366,13 @@ void SelectionDAGISel::SelectCodeCommon(SDNode *NodeToMatch, } else { assert(NodeToMatch->getOpcode() != ISD::DELETED_NODE && "NodeToMatch was removed partway through selection"); + SelectionDAG::DAGNodeDeletedListener NDL(*CurDAG, [&](SDNode *N, + SDNode *E) { + auto &Chain = ChainNodesMatched; + assert((!E || llvm::find(Chain, N) == Chain.end()) && + "Chain node replaced during MorphNode"); + Chain.erase(std::remove(Chain.begin(), Chain.end(), N), Chain.end()); + }); Res = MorphNode(NodeToMatch, TargetOpc, VTList, Ops, EmitNodeInfo); } -- cgit v1.2.3