- Make Boolean 'true' and 'false' singleton VM isolate objects.

vm/flow_graph_compiler_x64.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_FLOW_GRAPH_COMPILER_X64_H_
 #define VM_FLOW_GRAPH_COMPILER_X64_H_
 
 #ifndef VM_FLOW_GRAPH_COMPILER_H_
 #error Include flow_graph_compiler.h instead of flow_graph_compiler_x64.h.
 #endif
@@ skipping 189 matching lines @@
   void AddSlowPathCode(SlowPathCode* slow_path);
 
   void FinalizeExceptionHandlers(const Code& code);
   void FinalizePcDescriptors(const Code& code);
   void FinalizeDeoptInfo(const Code& code);
   void FinalizeStackmaps(const Code& code);
   void FinalizeVarDescriptors(const Code& code);
   void FinalizeComments(const Code& code);
   void FinalizeStaticCallTargetsTable(const Code& code);
 
-  const Bool& bool_true() const { return bool_true_; }
-  const Bool& bool_false() const { return bool_false_; }
   const Class& double_class() const { return double_class_; }
 
   // Returns true if the compiled function has a finally clause.
   bool HasFinally() const;
 
   static const int kLocalsOffsetFromFP = (-1 * kWordSize);
 
   void SaveLiveRegisters(LocationSummary* locs);
   void RestoreLiveRegisters(LocationSummary* locs);
 
@@ skipping 116 matching lines @@
   StackmapTableBuilder* stackmap_table_builder_;
   GrowableArray<BlockInfo*> block_info_;
   GrowableArray<CompilerDeoptInfo*> deopt_infos_;
   GrowableArray<SlowPathCode*> slow_path_code_;
   // Stores: [code offset, function, null(code)].
   const GrowableObjectArray& static_calls_target_table_;
   const bool is_optimizing_;
   // Set to true if optimized code has IC calls.
   bool may_reoptimize_;
 
-  const Bool& bool_true_;
-  const Bool& bool_false_;
   const Class& double_class_;
 
   ParallelMoveResolver parallel_move_resolver_;
 
   // Currently instructions generate deopt stubs internally by
   // calling AddDeoptStub.  To communicate deoptimization environment
   // that should be used when deoptimizing we store it in this variable.
   // In future AddDeoptStub should be moved out of the instruction template.
   Environment* pending_deoptimization_env_;
 
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_COMPILER_X64_H_