Remove unused function from print-changed=dot-cfg code

[jamieschmeiser]

Summary

Remove unused function from print-changed=dot-cfg code to silence a gcc compiler warning.

[uabelho]

Thanks!

llvm/lib/Passes/StandardInstrumentations.cpp

public:
   const DotCfgDiffNode &getNode(unsigned N) const {
     assert(N < Nodes.size() && "Unexpected index for node reference");
     return Nodes[N];
   }
 
 protected:
   // Return the string surrounded by HTML to make it the appropriate colour.
   std::string colourize(std::string S, IRChangeDiffType T) const;
-  // Return the string containing the colour to use as a Dot attribute.
-  std::string attribute(IRChangeDiffType T) const;
 
   void createNode(StringRef Label, const BlockDataT<DCData> &BD,
                   IRChangeDiffType T) {
     unsigned Pos = Nodes.size();
     Nodes.emplace_back(*this, Pos, BD, T);
     NodePosition.insert({Label, Pos});
   }
 

 }
 
 std::string DotCfgDiff::colourize(std::string S, IRChangeDiffType T) const {
   if (S.length() == 0)
     return S;
   return "<FONT COLOR=\"" + Colours[T] + "\">" + S + "</FONT>";
 }
 
-std::string DotCfgDiff::attribute(IRChangeDiffType T) const {
-  return "color=" + Colours[T];
-}
-
 std::string DotCfgDiffDisplayGraph::attribute(IRChangeDiffType T) const {
   return "color=" + Colours[T];
 }
 
 DotCfgDiff::DotCfgDiff(StringRef Title, const FuncDataT<DCData> &Before,
                        const FuncDataT<DCData> &After)
     : GraphName(Title.str()) {
   StringMap<IRChangeDiffType> EdgesMap;