[llvm] r268774 - SDAG: Don't leave dangling dead nodes after SelectCodeCommon

[Justin Bogner via llvm-commits]

Author: bogner
Date: Fri May  6 13:42:16 2016
New Revision: 268774

URL: http://llvm.org/viewvc/llvm-project?rev=268774&view=rev
Log:
SDAG: Don't leave dangling dead nodes after SelectCodeCommon

Relying on the caller to clean up after we've replaced all uses of a
node won't work when we've migrated to the `void Select(...)` API.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp?rev=268774&r1=268773&r2=268774&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp Fri May  6 13:42:16 2016
@@ -2179,7 +2179,7 @@ void SelectionDAGISel::UpdateChains(
       CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain);
 
       // If the node became dead and we haven't already seen it, delete it.
-      if (ChainNode->use_empty() &&
+      if (ChainNode != NodeToMatch && ChainNode->use_empty() &&
           !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), ChainNode))
         NowDeadNodes.push_back(ChainNode);
     }
@@ -2741,6 +2741,7 @@ SelectCodeCommon(SDNode *NodeToMatch, co
   case ISD::AssertZext:
     CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, 0),
                                       NodeToMatch->getOperand(0));
+    CurDAG->RemoveDeadNode(NodeToMatch);
     return nullptr;
   case ISD::INLINEASM: return Select_INLINEASM(NodeToMatch);
   case ISD::READ_REGISTER: return Select_READ_REGISTER(NodeToMatch);
@@ -3474,6 +3475,7 @@ SelectCodeCommon(SDNode *NodeToMatch, co
 
       assert(NodeToMatch->use_empty() &&
              "Didn't replace all uses of the node?");
+      CurDAG->RemoveDeadNode(NodeToMatch);
 
       // FIXME: We just return here, which interacts correctly with SelectRoot
       // above.  We should fix this to not return an SDNode* anymore.