Improve tracing of hydrogen stub compilation.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 58 matching lines @@
 
  private:
   SmartArrayPointer<HParameter*> parameters_;
   CompilationInfoWithZone info_;
   HContext* context_;
 };
 
 
 bool CodeStubGraphBuilderBase::BuildGraph() {
   if (FLAG_trace_hydrogen) {
+    const char* name = CodeStub::MajorName(stub()->MajorKey(), false);
     PrintF("-----------------------------------------------------------\n");
-    PrintF("Compiling stub using hydrogen\n");
+    PrintF("Compiling stub %s using hydrogen\n", name);
     HTracer::Instance()->TraceCompilation(&info_);
   }
   HBasicBlock* next_block = graph()->CreateBasicBlock();
   next_block->SetInitialEnvironment(graph()->start_environment());
   HGoto* jump = new(zone()) HGoto(next_block);
   graph()->entry_block()->Finish(jump);
   set_current_block(next_block);
 
   int major_key = stub()->MajorKey();
   CodeStubInterfaceDescriptor* descriptor =
@@ skipping 153 matching lines @@
 
 
 Handle<Code> TransitionElementsKindStub::GenerateCode() {
   CodeStubGraphBuilder<TransitionElementsKindStub> builder(this);
   LChunk* chunk = OptimizeGraph(builder.CreateGraph());
   return chunk->Codegen(Code::COMPILED_STUB);
 }
 
 
 } }  // namespace v8::internal