Minor simplification and cleanup of graph builder.

src/compiler/pipeline.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/pipeline.h"
 
 #include "src/base/platform/elapsed-timer.h"
 #include "src/compiler/ast-graph-builder.h"
 #include "src/compiler/code-generator.h"
 #include "src/compiler/graph-replay.h"
@@ skipping 67 matching lines @@
        << AsDOT(*graph);
   }
   if (VerifyGraphs()) Verifier::Run(graph);
 }
 
 
 class AstGraphBuilderWithPositions : public AstGraphBuilder {
  public:
   explicit AstGraphBuilderWithPositions(CompilationInfo* info, JSGraph* jsgraph,
                                         SourcePositionTable* source_positions)
-      : AstGraphBuilder(info, jsgraph, source_positions) {}
+      : AstGraphBuilder(info, jsgraph), source_positions_(source_positions) {}
+
+  bool CreateGraph() V8_OVERRIDE {
+    SourcePositionTable::Scope pos(source_positions_,
+                                   SourcePosition::Unknown());
+    return AstGraphBuilder::CreateGraph();
+  }
 
 #define DEF_VISIT(type)                                               \
   virtual void Visit##type(type* node) V8_OVERRIDE {                  \
-    SourcePositionTable::Scope pos(source_positions(),                \
+    SourcePositionTable::Scope pos(source_positions_,                 \
                                    SourcePosition(node->position())); \
     AstGraphBuilder::Visit##type(node);                               \
   }
   AST_NODE_LIST(DEF_VISIT)
 #undef DEF_VISIT
+
+ private:
+  SourcePositionTable* source_positions_;
 };
 
 
 static void TraceSchedule(Schedule* schedule) {
   if (!FLAG_trace_turbo) return;
   OFStream os(stdout);
   os << "-- Schedule --------------------------------------\n" << *schedule;
 }
 
 
@@ skipping 187 matching lines @@
 }
 
 
 void Pipeline::TearDown() {
   InstructionOperand::TearDownCaches();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8