Ensure that we don't mark weak heap references in the constant pool array.

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3164 matching lines @@
 // The format of the pool is:
 //   [0]: Field holding the first index which is a raw code target pointer entry
 //   [1]: Field holding the first index which is a heap pointer entry
 //   [2]: Field holding the first index which is a int32 entry
 //   [3]                      ... [first_code_ptr_index() - 1] : 64 bit entries
 //   [first_code_ptr_index()] ... [first_heap_ptr_index() - 1] : code pointers
 //   [first_heap_ptr_index()] ... [first_int32_index() - 1]    : heap pointers
 //   [first_int32_index()]    ... [length - 1]                 : 32 bit entries
 class ConstantPoolArray: public FixedArrayBase {
  public:
+  enum WeakObjectState {
+    NO_WEAK_OBJECTS,
+    WEAK_OBJECTS_IN_OPTIMIZED_CODE
+  };
+
   // Getters for the field storing the first index for different type entries.
   inline int first_code_ptr_index();
   inline int first_heap_ptr_index();
   inline int first_int64_index();
   inline int first_int32_index();
 
   // Getters for counts of different type entries.
   inline int count_of_code_ptr_entries();
   inline int count_of_heap_ptr_entries();
   inline int count_of_int64_entries();
   inline int count_of_int32_entries();
 
   // Setter and getter for pool elements.
   inline Address get_code_ptr_entry(int index);
   inline Object* get_heap_ptr_entry(int index);
   inline int64_t get_int64_entry(int index);
   inline int32_t get_int32_entry(int index);
   inline double get_int64_entry_as_double(int index);
 
+  // Setter and getter for weak objects state
+  inline void set_weak_object_state(WeakObjectState state);
+  inline WeakObjectState get_weak_object_state();
+
   inline void set(int index, Address value);
   inline void set(int index, Object* value);
   inline void set(int index, int64_t value);
   inline void set(int index, double value);
   inline void set(int index, int32_t value);
 
   // Set up initial state.
-  inline void SetEntryCounts(int number_of_int64_entries,
-                             int number_of_code_ptr_entries,
-                             int number_of_heap_ptr_entries,
-                             int number_of_int32_entries);
+  inline void Init(int number_of_int64_entries,
+                   int number_of_code_ptr_entries,
+                   int number_of_heap_ptr_entries,
+                   int number_of_int32_entries);
 
   // Copy operations
   MUST_USE_RESULT inline MaybeObject* Copy();
 
   // Garbage collection support.
   inline static int SizeFor(int number_of_int64_entries,
                             int number_of_code_ptr_entries,
                             int number_of_heap_ptr_entries,
                             int number_of_int32_entries) {
     return RoundUp(OffsetAt(number_of_int64_entries,
@@ skipping 22 matching lines @@
 
   // Casting.
   static inline ConstantPoolArray* cast(Object* obj);
 
   // Garbage collection support.
   Object** RawFieldOfElementAt(int index) {
     return HeapObject::RawField(this, OffsetOfElementAt(index));
   }
 
   // Layout description.
-  static const int kFirstCodePointerIndexOffset = FixedArray::kHeaderSize;
-  static const int kFirstHeapPointerIndexOffset =
-      kFirstCodePointerIndexOffset + kPointerSize;
-  static const int kFirstInt32IndexOffset =
-      kFirstHeapPointerIndexOffset + kPointerSize;
-  static const int kFirstOffset = kFirstInt32IndexOffset + kPointerSize;
+  static const int kArrayLayoutOffset = FixedArray::kHeaderSize;
+  static const int kFirstOffset = kArrayLayoutOffset + kPointerSize;
+
+  class NumberOfInt64EntriesField: public BitField<int, 0, 10> {};

[ulan, 2014/04/01 19:09:14]

How do we guarantee that the number of entries does not overflow?

[rmcilroy, 2014/04/07 14:03:55]

Good point (on Arm we never would due to checks in assembler-arm.cc, but we
should ensure this is always the case).  Added checks in heap.cc which return
FatalProcessOutOfMemory if length is wrong.

+  class NumberOfCodePtrEntriesField: public BitField<int, 10, 10> {};
+  class NumberOfHeapPtrEntriesField: public BitField<int, 20, 10> {};
+  class WeakObjectStateField: public BitField<WeakObjectState, 30, 2> {};
 
   // Dispatched behavior.
   void ConstantPoolIterateBody(ObjectVisitor* v);
 
   DECLARE_PRINTER(ConstantPoolArray)
   DECLARE_VERIFIER(ConstantPoolArray)
 
  private:
-  inline void set_first_code_ptr_index(int value);
-  inline void set_first_heap_ptr_index(int value);
-  inline void set_first_int32_index(int value);
-
   inline static int OffsetAt(int number_of_int64_entries,
                              int number_of_code_ptr_entries,
                              int number_of_heap_ptr_entries,
                              int number_of_int32_entries) {
     return kFirstOffset
         + (number_of_int64_entries * kInt64Size)
         + (number_of_code_ptr_entries * kPointerSize)
         + (number_of_heap_ptr_entries * kPointerSize)
         + (number_of_int32_entries * kInt32Size);
   }
@@ skipping 2260 matching lines @@
   bool CanDeoptAt(Address pc);
 
 #ifdef VERIFY_HEAP
   void VerifyEmbeddedObjectsDependency();
 #endif
 
   inline bool IsWeakObject(Object* object) {
     return is_optimized_code() && IsWeakObjectInOptimizedCode(object);
   }
 
-  inline bool IsWeakObjectInOptimizedCode(Object* object);
+  static inline bool IsWeakObjectInOptimizedCode(Object* object);
 
   // Max loop nesting marker used to postpose OSR. We don't take loop
   // nesting that is deeper than 5 levels into account.
   static const int kMaxLoopNestingMarker = 6;
 
   // Layout description.
   static const int kInstructionSizeOffset = HeapObject::kHeaderSize;
   static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize;
   static const int kHandlerTableOffset = kRelocationInfoOffset + kPointerSize;
   static const int kDeoptimizationDataOffset =
@@ skipping 5220 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_