diff --git a/src/compiler/graph-visualizer.h b/src/compiler/graph-visualizer.h
index 12532ba..3dd66ea 100644
--- a/src/compiler/graph-visualizer.h
+++ b/src/compiler/graph-visualizer.h
@@ -5,25 +5,80 @@
 #ifndef V8_COMPILER_GRAPH_VISUALIZER_H_
 #define V8_COMPILER_GRAPH_VISUALIZER_H_
 
-#include "src/v8.h"
+#include <iosfwd>
 
 namespace v8 {
 namespace internal {
 
-class OStream;
+class CompilationInfo;
 
 namespace compiler {
 
 class Graph;
+class InstructionSequence;
+class RegisterAllocator;
+class Schedule;
+class SourcePositionTable;
+
 
 struct AsDOT {
   explicit AsDOT(const Graph& g) : graph(g) {}
   const Graph& graph;
 };
 
-OStream& operator<<(OStream& os, const AsDOT& ad);
-}
-}
-}  // namespace v8::internal::compiler
+std::ostream& operator<<(std::ostream& os, const AsDOT& ad);
+
+
+struct AsJSON {
+  explicit AsJSON(const Graph& g) : graph(g) {}
+  const Graph& graph;
+};
+
+std::ostream& operator<<(std::ostream& os, const AsJSON& ad);
+
+struct AsRPO {
+  explicit AsRPO(const Graph& g) : graph(g) {}
+  const Graph& graph;
+};
+
+std::ostream& operator<<(std::ostream& os, const AsRPO& ad);
+
+
+struct AsC1VCompilation {
+  explicit AsC1VCompilation(const CompilationInfo* info) : info_(info) {}
+  const CompilationInfo* info_;
+};
+
+
+struct AsC1V {
+  AsC1V(const char* phase, const Schedule* schedule,
+        const SourcePositionTable* positions = NULL,
+        const InstructionSequence* instructions = NULL)
+      : schedule_(schedule),
+        instructions_(instructions),
+        positions_(positions),
+        phase_(phase) {}
+  const Schedule* schedule_;
+  const InstructionSequence* instructions_;
+  const SourcePositionTable* positions_;
+  const char* phase_;
+};
+
+struct AsC1VAllocator {
+  explicit AsC1VAllocator(const char* phase,
+                          const RegisterAllocator* allocator = NULL)
+      : phase_(phase), allocator_(allocator) {}
+  const char* phase_;
+  const RegisterAllocator* allocator_;
+};
+
+std::ostream& operator<<(std::ostream& os, const AsDOT& ad);
+std::ostream& operator<<(std::ostream& os, const AsC1VCompilation& ac);
+std::ostream& operator<<(std::ostream& os, const AsC1V& ac);
+std::ostream& operator<<(std::ostream& os, const AsC1VAllocator& ac);
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_COMPILER_GRAPH_VISUALIZER_H_