[llvm-commits] [llvm] r128730 - /llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

[Evan Cheng]

Author: evancheng
Date: Fri Apr  1 14:57:01 2011
New Revision: 128730

URL: http://llvm.org/viewvc/llvm-project?rev=128730&view=rev
Log:
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Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp?rev=128730&r1=128729&r2=128730&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp Fri Apr  1 14:57:01 2011
@@ -4929,9 +4929,11 @@
                          &ReturnValues[0], ReturnValues.size()));
   }
 
-  // As a special case, a null chain means that a tail call has been emitted and
-  // the DAG root is already updated.
+  // Assign order to nodes here. If the call does not produce a result, it won't
+  // be mapped to a SDNode and visit() will not assign it an order number.
   if (!Result.second.getNode()) {
+    // As a special case, a null chain means that a tail call has been emitted and
+    // the DAG root is already updated.
     HasTailCall = true;
     ++SDNodeOrder;
     AssignOrderingToNode(DAG.getRoot().getNode());