[interpreter, debugger] support debug breaks via bytecode array copy

src/objects.h

 // Copyright 2015 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.
 
 #ifndef V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 4484 matching lines @@
   inline int instruction_size();
 
   int SourcePosition(int offset);
   int SourceStatementPosition(int offset);
 
   DECLARE_PRINTER(BytecodeArray)
   DECLARE_VERIFIER(BytecodeArray)
 
   void Disassemble(std::ostream& os);
 
+  void CopyTo(BytecodeArray* to);
+
   // Layout description.
   static const int kFrameSizeOffset = FixedArrayBase::kHeaderSize;
   static const int kParameterSizeOffset = kFrameSizeOffset + kIntSize;
   static const int kConstantPoolOffset = kParameterSizeOffset + kIntSize;
   static const int kHandlerTableOffset = kConstantPoolOffset + kPointerSize;
   static const int kSourcePositionTableOffset =
       kHandlerTableOffset + kPointerSize;
   static const int kHeaderSize = kSourcePositionTableOffset + kPointerSize;
 
   // Maximal memory consumption for a single BytecodeArray.
@@ skipping 6147 matching lines @@
                             int source_position, int statement_position,
                             Handle<Object> break_point_object);
   // Get the break point objects for a code offset.
   Handle<Object> GetBreakPointObjects(int code_offset);
   // Find the break point info holding this break point object.
   static Handle<Object> FindBreakPointInfo(Handle<DebugInfo> debug_info,
                                            Handle<Object> break_point_object);
   // Get the number of break points for this function.
   int GetBreakPointCount();
 
+  static Smi* uninitialized() { return Smi::FromInt(0); }
+
   DECLARE_CAST(DebugInfo)
 
   // Dispatched behavior.
   DECLARE_PRINTER(DebugInfo)
   DECLARE_VERIFIER(DebugInfo)
 
   static const int kSharedFunctionInfoIndex = Struct::kHeaderSize;
   static const int kAbstractCodeIndex = kSharedFunctionInfoIndex + kPointerSize;
   static const int kBreakPointsStateIndex = kAbstractCodeIndex + kPointerSize;
   static const int kSize = kBreakPointsStateIndex + kPointerSize;
@@ skipping 174 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_