2 files changed, 36 insertions, 4 deletions
diff --git a/include/llvm/Support/DOTGraphTraits.h b/include/llvm/Support/DOTGraphTraits.h
index 080c09b5f4..2367c0e260 100644
--- a/include/llvm/Support/DOTGraphTraits.h
+++ b/include/llvm/Support/DOTGraphTraits.h
@@ -100,6 +100,24 @@ struct DefaultDOTGraphTraits {
     return I;
   }
 
+  /// hasEdgeDestLabels - If this function returns true, the graph is able
+  /// to provide labels for edge destinations.
+  static bool hasEdgeDestLabels() {
+    return false;
+  }
+
+  /// numEdgeDestLabels - If hasEdgeDestLabels, this function returns the
+  /// number of incoming edge labels the given node has.
+  static unsigned numEdgeDestLabels(const void *Node) {
+    return 0;
+  }
+
+  /// getEdgeDestLabel - If hasEdgeDestLabels, this function returns the
+  /// incoming edge label with the given index in the given node.
+  static std::string getEdgeDestLabel(const void *Node, unsigned i) {
+    return "";
+  }
+
   /// addCustomGraphFeatures - If a graph is made up of more than just
   /// straight-forward nodes and edges, this is the place to put all of the
   /// custom stuff necessary.  The GraphWriter object, instantiated with your
diff --git a/include/llvm/Support/GraphWriter.h b/include/llvm/Support/GraphWriter.h
index afb2f545bb..20e85cce7d 100644
--- a/include/llvm/Support/GraphWriter.h
+++ b/include/llvm/Support/GraphWriter.h
@@ -146,11 +146,11 @@ public:
 
       for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i) {
         if (i) O << "|";
-        O << "<g" << i << ">" << DOTTraits::getEdgeSourceLabel(Node, EI);
+        O << "<s" << i << ">" << DOTTraits::getEdgeSourceLabel(Node, EI);
       }
 
       if (EI != EE)
-        O << "|<g64>truncated...";
+        O << "|<s64>truncated...";
       O << "}";
       if (DOTTraits::renderGraphFromBottomUp()) O << "|";
     }
@@ -163,6 +163,20 @@ public:
         O << "|" << (void*)Node;
     }
 
+    if (DOTTraits::hasEdgeDestLabels()) {
+      O << "|{";
+
+      unsigned i = 0, e = DOTTraits::numEdgeDestLabels(Node);
+      for (; i != e && i != 64; ++i) {
+        if (i) O << "|";
+        O << "<d" << i << ">" << DOTTraits::getEdgeDestLabel(Node, i);
+      }
+
+      if (i != e)
+        O << "|<d64>truncated...";
+      O << "}";
+    }
+
     O << "}\"];\n";   // Finish printing the "node" line
 
     // Output all of the edges now
@@ -223,10 +237,10 @@ public:
 
     O << "\tNode" << SrcNodeID;
     if (SrcNodePort >= 0)
-      O << ":g" << SrcNodePort;
+      O << ":s" << SrcNodePort;
     O << " -> Node" << reinterpret_cast<const void*>(DestNodeID);
     if (DestNodePort >= 0)
-      O << ":g" << DestNodePort;
+      O << ":d" << DestNodePort;
 
     if (!Attrs.empty())
       O << "[" << Attrs << "]";