[Interpreter] Add BytecodeArray class and add to SharedFunctionInfo.

src/objects.h

 // Copyright 2012 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 55 matching lines @@
 //           - JSGlobalObject
 //           - JSBuiltinsObject
 //         - JSGlobalProxy
 //         - JSValue
 //           - JSDate
 //         - JSMessageObject
 //       - JSProxy
 //         - JSFunctionProxy
 //     - FixedArrayBase
 //       - ByteArray
+//       - BytecodeArray
 //       - FixedArray
 //         - DescriptorArray
 //         - HashTable
 //           - Dictionary
 //           - StringTable
 //           - CompilationCacheTable
 //           - CodeCacheHashTable
 //           - MapCache
 //         - OrderedHashTable
 //           - OrderedHashSet
@@ skipping 305 matching lines @@
   V(CODE_TYPE)                                                  \
   V(ODDBALL_TYPE)                                               \
   V(CELL_TYPE)                                                  \
   V(PROPERTY_CELL_TYPE)                                         \
                                                                 \
   V(HEAP_NUMBER_TYPE)                                           \
   V(MUTABLE_HEAP_NUMBER_TYPE)                                   \
   V(FLOAT32X4_TYPE)                                             \
   V(FOREIGN_TYPE)                                               \
   V(BYTE_ARRAY_TYPE)                                            \
+  V(BYTECODE_ARRAY_TYPE)                                        \
   V(FREE_SPACE_TYPE)                                            \
   /* Note: the order of these external array */                 \
   /* types is relied upon in */                                 \
   /* Object::IsExternalArray(). */                              \
   V(EXTERNAL_INT8_ARRAY_TYPE)                                   \
   V(EXTERNAL_UINT8_ARRAY_TYPE)                                  \
   V(EXTERNAL_INT16_ARRAY_TYPE)                                  \
   V(EXTERNAL_UINT16_ARRAY_TYPE)                                 \
   V(EXTERNAL_INT32_ARRAY_TYPE)                                  \
   V(EXTERNAL_UINT32_ARRAY_TYPE)                                 \
@@ skipping 276 matching lines @@
   CODE_TYPE,
   ODDBALL_TYPE,
 
   // "Data", objects that cannot contain non-map-word pointers to heap
   // objects.
   HEAP_NUMBER_TYPE,
   MUTABLE_HEAP_NUMBER_TYPE,
   FLOAT32X4_TYPE,  // FIRST_SIMD_TYPE, LAST_SIMD_TYPE
   FOREIGN_TYPE,
   BYTE_ARRAY_TYPE,
+  BYTECODE_ARRAY_TYPE,
   FREE_SPACE_TYPE,
   EXTERNAL_INT8_ARRAY_TYPE,  // FIRST_EXTERNAL_ARRAY_TYPE
   EXTERNAL_UINT8_ARRAY_TYPE,
   EXTERNAL_INT16_ARRAY_TYPE,
   EXTERNAL_UINT16_ARRAY_TYPE,
   EXTERNAL_INT32_ARRAY_TYPE,
   EXTERNAL_UINT32_ARRAY_TYPE,
   EXTERNAL_FLOAT32_ARRAY_TYPE,
   EXTERNAL_FLOAT64_ARRAY_TYPE,
   EXTERNAL_UINT8_CLAMPED_ARRAY_TYPE,  // LAST_EXTERNAL_ARRAY_TYPE
@@ skipping 246 matching lines @@
   V(FixedInt8Array)                \
   V(FixedUint16Array)              \
   V(FixedInt16Array)               \
   V(FixedUint32Array)              \
   V(FixedInt32Array)               \
   V(FixedFloat32Array)             \
   V(FixedFloat64Array)             \
   V(FixedUint8ClampedArray)        \
   V(Float32x4)                     \
   V(ByteArray)                     \
+  V(BytecodeArray)                 \
   V(FreeSpace)                     \
   V(JSReceiver)                    \
   V(JSObject)                      \
   V(JSContextExtensionObject)      \
   V(JSGeneratorObject)             \
   V(JSModule)                      \
   V(LayoutDescriptor)              \
   V(Map)                           \
   V(DescriptorArray)               \
   V(TransitionArray)               \
@@ skipping 3280 matching lines @@
   // Maximal memory consumption for a single ByteArray.
   static const int kMaxSize = 512 * MB;
   // Maximal length of a single ByteArray.
   static const int kMaxLength = kMaxSize - kHeaderSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(ByteArray);
 };
 
 
+// BytecodeArray represents a sequence of interpreter bytecodes.
+class BytecodeArray : public FixedArrayBase {
+ public:
+  static int SizeFor(int length) {
+    return OBJECT_POINTER_ALIGN(kHeaderSize + length);
+  }
+
+  // Setter and getter
+  inline byte get(int index);
+  inline void set(int index, byte value);
+
+  // Returns data start address.
+  inline Address GetFirstBytecodeAddress();
+
+  // Accessors for frame size and the number of locals
+  inline int frame_size() const;
+  inline void set_frame_size(int value);
+  inline int number_of_locals() const;
+  inline void set_number_of_locals(int value);
+
+  DECLARE_CAST(BytecodeArray)
+
+  // Dispatched behavior.
+  inline int BytecodeArraySize() { return SizeFor(this->length()); }
+
+  DECLARE_PRINTER(BytecodeArray)
+  DECLARE_VERIFIER(BytecodeArray)
+
+  void Disassemble(std::ostream& os);
+
+  // Layout description.
+  static const int kFrameSizeOffset = ByteArray::kHeaderSize;
+  static const int kNumberOfLocalsOffset = kFrameSizeOffset + kIntSize;
+  static const int kHeaderSize = kNumberOfLocalsOffset + kIntSize;
+
+  static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize);
+
+  // Maximal memory consumption for a single BytecodeArray.
+  static const int kMaxSize = ByteArray::kMaxSize;
+  // Maximal length of a single BytecodeArray.
+  static const int kMaxLength = kMaxSize - kHeaderSize;
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(BytecodeArray);
+};
+
+
 // FreeSpace are fixed-size free memory blocks used by the heap and GC.
 // They look like heap objects (are heap object tagged and have a map) so that
 // the heap remains iterable.  They have a size and a next pointer.
 // The next pointer is the raw address of the next FreeSpace object (or NULL)
 // in the free list.
 class FreeSpace: public HeapObject {
  public:
   // [size]: size of the free space including the header.
   inline int size() const;
   inline void set_size(int value);
@@ skipping 2379 matching lines @@
   // (increasingly) from crankshafted code where sufficient feedback isn't
   // available.
   DECL_ACCESSORS(feedback_vector, TypeFeedbackVector)
 
   // Unconditionally clear the type feedback vector (including vector ICs).
   void ClearTypeFeedbackInfo();
 
   // Clear the type feedback vector with a more subtle policy at GC time.
   void ClearTypeFeedbackInfoAtGCTime();
 
+  // [bytecode_array]: Interpreter bytecodes.
+  DECL_ACCESSORS(bytecode_array, BytecodeArray)

[Michael Starzinger, 2015/07/22 07:20:54]

nit: These declarations have become obsolete, let's drop them. The getter is
declared below and if we ever need a setter, we should also explicitly declare
it below.

[oth, 2015/07/22 08:50:00]

Done.

+
 #if TRACE_MAPS
   // [unique_id] - For --trace-maps purposes, an identifier that's persistent
   // even if the GC moves this SharedFunctionInfo.
   inline int unique_id() const;
   inline void set_unique_id(int value);
 #endif
 
   // [instance class name]: class name for instances.
   DECL_ACCESSORS(instance_class_name, Object)
 
   // [function data]: This field holds some additional data for function.
-  // Currently it either has FunctionTemplateInfo to make benefit the API
-  // or Smi identifying a builtin function.
+  // Currently it has one of:
+  //  - a FunctionTemplateInfo to make benefit the API [IsApiFunction()].
+  //  - a Smi identifying a builtin function [HasBuiltinFunctionId()].
+  //  - a bytecode array for the interpreter [HasBytecodeArray()].

[rmcilroy, 2015/07/22 07:44:00]

nit /s/bytecode array/BytecodeArray

[oth, 2015/07/22 08:50:00]

Done.

   // In the long run we don't want all functions to have this field but
   // we can fix that when we have a better model for storing hidden data
   // on objects.
   DECL_ACCESSORS(function_data, Object)
 
   inline bool IsApiFunction();
   inline FunctionTemplateInfo* get_api_func_data();
   inline bool HasBuiltinFunctionId();
   inline BuiltinFunctionId builtin_function_id();
+  inline bool HasBytecodeArray();
+  inline BytecodeArray* bytecode_array();
 
   // [script info]: Script from which the function originates.
   DECL_ACCESSORS(script, Object)
 
   // [num_literals]: Number of literals used by this function.
   inline int num_literals() const;
   inline void set_num_literals(int value);
 
   // [start_position_and_type]: Field used to store both the source code
   // position, whether or not the function is a function expression,
@@ skipping 4130 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_