[interpreter, debugger] abstraction for source position calculation.

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 109 matching lines @@
 //       - Bool32x4
 //       - Int16x8
 //       - Uint16x8
 //       - Bool16x8
 //       - Int8x16
 //       - Uint8x16
 //       - Bool8x16
 //     - Cell
 //     - PropertyCell
 //     - Code
+//     - AbstractCode, a wrapper around Code or BytecodeArray
 //     - Map
 //     - Oddball
 //     - Foreign
 //     - SharedFunctionInfo
 //     - Struct
 //       - Box
 //       - AccessorInfo
 //       - AccessorPair
 //       - AccessCheckInfo
 //       - InterceptorInfo
@@ skipping 800 matching lines @@
   V(FixedDoubleArray)              \
   V(WeakFixedArray)                \
   V(ArrayList)                     \
   V(Context)                       \
   V(ScriptContextTable)            \
   V(NativeContext)                 \
   V(ScopeInfo)                     \
   V(JSBoundFunction)               \
   V(JSFunction)                    \
   V(Code)                          \
+  V(AbstractCode)                  \
   V(Oddball)                       \
   V(SharedFunctionInfo)            \
   V(JSValue)                       \
   V(JSDate)                        \
   V(JSMessageObject)               \
   V(StringWrapper)                 \
   V(Foreign)                       \
   V(Boolean)                       \
   V(JSArray)                       \
   V(JSArrayBuffer)                 \
@@ skipping 3464 matching lines @@
 
   // Accessors for source position table containing mappings between byte code
   // offset and source position.
   DECL_ACCESSORS(source_position_table, FixedArray)
 
   DECLARE_CAST(BytecodeArray)
 
   // Dispatched behavior.
   inline int BytecodeArraySize();
 
+  inline int instruction_size();
+
+  int SourcePosition(int offset);
+
   DECLARE_PRINTER(BytecodeArray)
   DECLARE_VERIFIER(BytecodeArray)
 
   void Disassemble(std::ostream& os);
 
   // 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;
@@ skipping 893 matching lines @@
 
   // Code aging -- platform-specific
   static void PatchPlatformCodeAge(Isolate* isolate,
                                    byte* sequence, Age age,
                                    MarkingParity parity);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Code);
 };
 
 
+class AbstractCode : public HeapObject {
+ public:
+  int SourcePosition(int offset);
+
+  DECLARE_CAST(AbstractCode)
+  inline Code* GetCode();
+  inline BytecodeArray* GetBytecodeArray();
+};
+
+
 // Dependent code is a singly linked list of fixed arrays. Each array contains
 // code objects in weak cells for one dependent group. The suffix of the array
 // can be filled with the undefined value if the number of codes is less than
 // the length of the array.
 //
 // +------+-----------------+--------+--------+-----+--------+-----------+-----+
 // | next | count & group 1 | code 1 | code 2 | ... | code n | undefined | ... |
 // +------+-----------------+--------+--------+-----+--------+-----------+-----+
 //    |
 //    V
@@ skipping 1020 matching lines @@
   // this through. Encoded in the 'flags' field.
   inline v8::ScriptOriginOptions origin_options();
   inline void set_origin_options(ScriptOriginOptions origin_options);
 
   DECLARE_CAST(Script)
 
   // If script source is an external string, check that the underlying
   // resource is accessible. Otherwise, always return true.
   inline bool HasValidSource();
 
-  // Convert code position into column number.
-  static int GetColumnNumber(Handle<Script> script, int code_pos);
+  // Convert code offset into column number.
+  static int GetColumnNumber(Handle<Script> script, int code_offset);
 
-  // Convert code position into (zero-based) line number.
+  // Convert code offset into (zero-based) line number.
   // The non-handlified version does not allocate, but may be much slower.
-  static int GetLineNumber(Handle<Script> script, int code_pos);
+  static int GetLineNumber(Handle<Script> script, int code_offset);
   int GetLineNumber(int code_pos);
 
   static Handle<Object> GetNameOrSourceURL(Handle<Script> script);
 
-  // Init line_ends array with code positions of line ends inside script source.
+  // Init line_ends array with source code positions of line ends.
   static void InitLineEnds(Handle<Script> script);
 
   // Get the JS object wrapping the given script; create it if none exists.
   static Handle<JSObject> GetWrapper(Handle<Script> script);
 
   // Look through the list of existing shared function infos to find one
   // that matches the function literal.  Return empty handle if not found.
   MaybeHandle<SharedFunctionInfo> FindSharedFunctionInfo(FunctionLiteral* fun);
 
   // Iterate over all script objects on the heap.
@@ skipping 115 matching lines @@
 
 // SharedFunctionInfo describes the JSFunction information that can be
 // shared by multiple instances of the function.
 class SharedFunctionInfo: public HeapObject {
  public:
   // [name]: Function name.
   DECL_ACCESSORS(name, Object)
 
   // [code]: Function code.
   DECL_ACCESSORS(code, Code)
+
+  // Retrieve interpreter bytecode or unoptimized function code.
+  inline AbstractCode* AbstractCode();
+
   inline void ReplaceCode(Code* code);
 
   // [optimized_code_map]: Map from native context to optimized code
   // and a shared literals array.
   DECL_ACCESSORS(optimized_code_map, FixedArray)
 
   // Returns entry from optimized code map for specified context and OSR entry.
   // Note that {code == nullptr, literals == nullptr} indicates no matching
   // entry has been found, whereas {code, literals == nullptr} indicates that
   // code is context-independent.
@@ skipping 4027 matching lines @@
 class DebugInfo: public Struct {
  public:
   // The shared function info for the source being debugged.
   DECL_ACCESSORS(shared, SharedFunctionInfo)
   // Code object for the patched code. This code object is the code object
   // currently active for the function.
   DECL_ACCESSORS(code, Code)
   // Fixed array holding status information for each active break point.
   DECL_ACCESSORS(break_points, FixedArray)
 
-  // Check if there is a break point at a code position.
-  bool HasBreakPoint(int code_position);
-  // Get the break point info object for a code position.
-  Object* GetBreakPointInfo(int code_position);
+  // Check if there is a break point at a code offset.
+  bool HasBreakPoint(int code_offset);
+  // Get the break point info object for a code offset.
+  Object* GetBreakPointInfo(int code_offset);
   // Clear a break point.
-  static void ClearBreakPoint(Handle<DebugInfo> debug_info,
-                              int code_position,
+  static void ClearBreakPoint(Handle<DebugInfo> debug_info, int code_offset,
                               Handle<Object> break_point_object);
   // Set a break point.
-  static void SetBreakPoint(Handle<DebugInfo> debug_info, int code_position,
+  static void SetBreakPoint(Handle<DebugInfo> debug_info, int code_offset,
                             int source_position, int statement_position,
                             Handle<Object> break_point_object);
-  // Get the break point objects for a code position.
-  Handle<Object> GetBreakPointObjects(int code_position);
+  // 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();
 
   DECLARE_CAST(DebugInfo)
 
   // Dispatched behavior.
   DECLARE_PRINTER(DebugInfo)
   DECLARE_VERIFIER(DebugInfo)
 
   static const int kSharedFunctionInfoIndex = Struct::kHeaderSize;
   static const int kCodeIndex = kSharedFunctionInfoIndex + kPointerSize;
   static const int kBreakPointsStateIndex = kCodeIndex + kPointerSize;
   static const int kSize = kBreakPointsStateIndex + kPointerSize;
 
   static const int kEstimatedNofBreakPointsInFunction = 16;
 
  private:
   static const int kNoBreakPointInfo = -1;
 
-  // Lookup the index in the break_points array for a code position.
-  int GetBreakPointInfoIndex(int code_position);
+  // Lookup the index in the break_points array for a code offset.
+  int GetBreakPointInfoIndex(int code_offset);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(DebugInfo);
 };
 
 
 // The BreakPointInfo class holds information for break points set in a
 // function. The DebugInfo object holds a BreakPointInfo object for each code
 // position with one or more break points.
 class BreakPointInfo: public Struct {
  public:
-  // The position in the code for the break point.
-  DECL_INT_ACCESSORS(code_position)
+  // The code offset for the break point.
+  DECL_INT_ACCESSORS(code_offset)
   // The position in the source for the break position.
   DECL_INT_ACCESSORS(source_position)
   // The position in the source for the last statement before this break
   // position.
   DECL_INT_ACCESSORS(statement_position)
   // List of related JavaScript break points.
   DECL_ACCESSORS(break_point_objects, Object)
 
   // Removes a break point.
   static void ClearBreakPoint(Handle<BreakPointInfo> info,
                               Handle<Object> break_point_object);
   // Set a break point.
   static void SetBreakPoint(Handle<BreakPointInfo> info,
                             Handle<Object> break_point_object);
   // Check if break point info has this break point object.
   static bool HasBreakPointObject(Handle<BreakPointInfo> info,
                                   Handle<Object> break_point_object);
-  // Get the number of break points for this code position.
+  // Get the number of break points for this code offset.
   int GetBreakPointCount();
 
   DECLARE_CAST(BreakPointInfo)
 
   // Dispatched behavior.
   DECLARE_PRINTER(BreakPointInfo)
   DECLARE_VERIFIER(BreakPointInfo)
 
-  static const int kCodePositionIndex = Struct::kHeaderSize;
-  static const int kSourcePositionIndex = kCodePositionIndex + kPointerSize;
+  static const int kCodeOffsetIndex = Struct::kHeaderSize;
+  static const int kSourcePositionIndex = kCodeOffsetIndex + kPointerSize;
   static const int kStatementPositionIndex =
       kSourcePositionIndex + kPointerSize;
   static const int kBreakPointObjectsIndex =
       kStatementPositionIndex + kPointerSize;
   static const int kSize = kBreakPointObjectsIndex + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(BreakPointInfo);
 };
 
@@ skipping 115 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_