Make object accessors more const-correct.

Getting closer to making our IsFOO and FOO::cast methods const-correct...

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/349623002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21897 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects-inl.h

@@ -67,30 +67,30 @@ PropertyDetails PropertyDetails::AsDeleted() const {
   }
 
 
-#define INT_ACCESSORS(holder, name, offset)                             \
-  int holder::name() { return READ_INT_FIELD(this, offset); }           \
+#define INT_ACCESSORS(holder, name, offset)                                   \
+  int holder::name() const { return READ_INT_FIELD(this, offset); }           \
   void holder::set_##name(int value) { WRITE_INT_FIELD(this, offset, value); }
 
 
-#define ACCESSORS(holder, name, type, offset)                           \
-  type* holder::name() { return type::cast(READ_FIELD(this, offset)); } \
-  void holder::set_##name(type* value, WriteBarrierMode mode) {         \
-    WRITE_FIELD(this, offset, value);                                   \
-    CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode);    \
+#define ACCESSORS(holder, name, type, offset)                                 \
+  type* holder::name() const { return type::cast(READ_FIELD(this, offset)); } \
+  void holder::set_##name(type* value, WriteBarrierMode mode) {               \
+    WRITE_FIELD(this, offset, value);                                         \
+    CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode);          \
   }
 
 
 // Getter that returns a tagged Smi and setter that writes a tagged Smi.
-#define ACCESSORS_TO_SMI(holder, name, offset)                          \
-  Smi* holder::name() { return Smi::cast(READ_FIELD(this, offset)); }   \
-  void holder::set_##name(Smi* value, WriteBarrierMode mode) {          \
-    WRITE_FIELD(this, offset, value);                                   \
+#define ACCESSORS_TO_SMI(holder, name, offset)                              \
+  Smi* holder::name() const { return Smi::cast(READ_FIELD(this, offset)); } \
+  void holder::set_##name(Smi* value, WriteBarrierMode mode) {              \
+    WRITE_FIELD(this, offset, value);                                       \
   }
 
 
 // Getter that returns a Smi as an int and writes an int as a Smi.
 #define SMI_ACCESSORS(holder, name, offset)             \
-  int holder::name() {                                  \
+  int holder::name() const {                            \
     Object* value = READ_FIELD(this, offset);           \
     return Smi::cast(value)->value();                   \
   }                                                     \
@@ -99,7 +99,7 @@ PropertyDetails PropertyDetails::AsDeleted() const {
   }
 
 #define SYNCHRONIZED_SMI_ACCESSORS(holder, name, offset)    \
-  int holder::synchronized_##name() {                       \
+  int holder::synchronized_##name() const {                 \
     Object* value = ACQUIRE_READ_FIELD(this, offset);       \
     return Smi::cast(value)->value();                       \
   }                                                         \
@@ -108,7 +108,7 @@ PropertyDetails PropertyDetails::AsDeleted() const {
   }
 
 #define NOBARRIER_SMI_ACCESSORS(holder, name, offset)          \
-  int holder::nobarrier_##name() {                             \
+  int holder::nobarrier_##name() const {                       \
     Object* value = NOBARRIER_READ_FIELD(this, offset);        \
     return Smi::cast(value)->value();                          \
   }                                                            \
@@ -117,13 +117,13 @@ PropertyDetails PropertyDetails::AsDeleted() const {
   }
 
 #define BOOL_GETTER(holder, field, name, offset)           \
-  bool holder::name() {                                    \
+  bool holder::name() const {                              \
     return BooleanBit::get(field(), offset);               \
   }                                                        \
 
 
 #define BOOL_ACCESSORS(holder, field, name, offset)        \
-  bool holder::name() {                                    \
+  bool holder::name() const {                              \
     return BooleanBit::get(field(), offset);               \
   }                                                        \
   void holder::set_##name(bool value) {                    \
@@ -1121,16 +1121,19 @@ bool JSProxy::HasElementWithHandler(Handle<JSProxy> proxy, uint32_t index) {
 #define FIELD_ADDR(p, offset) \
   (reinterpret_cast<byte*>(p) + offset - kHeapObjectTag)
 
+#define FIELD_ADDR_CONST(p, offset) \
+  (reinterpret_cast<const byte*>(p) + offset - kHeapObjectTag)
+
 #define READ_FIELD(p, offset) \
-  (*reinterpret_cast<Object**>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<Object* const*>(FIELD_ADDR_CONST(p, offset)))
 
 #define ACQUIRE_READ_FIELD(p, offset)           \
   reinterpret_cast<Object*>(base::Acquire_Load( \
-      reinterpret_cast<base::AtomicWord*>(FIELD_ADDR(p, offset))))
+      reinterpret_cast<const base::AtomicWord*>(FIELD_ADDR_CONST(p, offset))))
 
 #define NOBARRIER_READ_FIELD(p, offset)           \
   reinterpret_cast<Object*>(base::NoBarrier_Load( \
-      reinterpret_cast<base::AtomicWord*>(FIELD_ADDR(p, offset))))
+      reinterpret_cast<const base::AtomicWord*>(FIELD_ADDR_CONST(p, offset))))
 
 #define WRITE_FIELD(p, offset, value) \
   (*reinterpret_cast<Object**>(FIELD_ADDR(p, offset)) = value)
@@ -1163,17 +1166,17 @@ bool JSProxy::HasElementWithHandler(Handle<JSProxy> proxy, uint32_t index) {
 
 #ifndef V8_TARGET_ARCH_MIPS
   #define READ_DOUBLE_FIELD(p, offset) \
-    (*reinterpret_cast<double*>(FIELD_ADDR(p, offset)))
+    (*reinterpret_cast<const double*>(FIELD_ADDR_CONST(p, offset)))
 #else  // V8_TARGET_ARCH_MIPS
   // Prevent gcc from using load-double (mips ldc1) on (possibly)
   // non-64-bit aligned HeapNumber::value.
-  static inline double read_double_field(void* p, int offset) {
+  static inline double read_double_field(const void* p, int offset) {
     union conversion {
       double d;
       uint32_t u[2];
     } c;
-    c.u[0] = (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset)));
-    c.u[1] = (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset + 4)));
+    c.u[0] = (*reinterpret_cast<uint32_t*>(FIELD_ADDR_CONST(p, offset)));
+    c.u[1] = (*reinterpret_cast<uint32_t*>(FIELD_ADDR_CONST(p, offset + 4)));
     return c.d;
   }
   #define READ_DOUBLE_FIELD(p, offset) read_double_field(p, offset)
@@ -1201,43 +1204,43 @@ bool JSProxy::HasElementWithHandler(Handle<JSProxy> proxy, uint32_t index) {
 
 
 #define READ_INT_FIELD(p, offset) \
-  (*reinterpret_cast<int*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const int*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_INT_FIELD(p, offset, value) \
   (*reinterpret_cast<int*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_INTPTR_FIELD(p, offset) \
-  (*reinterpret_cast<intptr_t*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const intptr_t*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_INTPTR_FIELD(p, offset, value) \
   (*reinterpret_cast<intptr_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_UINT32_FIELD(p, offset) \
-  (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const uint32_t*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_UINT32_FIELD(p, offset, value) \
   (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_INT32_FIELD(p, offset) \
-  (*reinterpret_cast<int32_t*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const int32_t*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_INT32_FIELD(p, offset, value) \
   (*reinterpret_cast<int32_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_INT64_FIELD(p, offset) \
-  (*reinterpret_cast<int64_t*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const int64_t*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_INT64_FIELD(p, offset, value) \
   (*reinterpret_cast<int64_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_SHORT_FIELD(p, offset) \
-  (*reinterpret_cast<uint16_t*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const uint16_t*>(FIELD_ADDR_CONST(p, offset)))
 
 #define WRITE_SHORT_FIELD(p, offset, value) \
   (*reinterpret_cast<uint16_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_BYTE_FIELD(p, offset) \
-  (*reinterpret_cast<byte*>(FIELD_ADDR(p, offset)))
+  (*reinterpret_cast<const byte*>(FIELD_ADDR_CONST(p, offset)))
 
 #define NOBARRIER_READ_BYTE_FIELD(p, offset) \
   static_cast<byte>(base::NoBarrier_Load(    \
@@ -1252,11 +1255,11 @@ bool JSProxy::HasElementWithHandler(Handle<JSProxy> proxy, uint32_t index) {
       static_cast<base::Atomic8>(value));
 
 Object** HeapObject::RawField(HeapObject* obj, int byte_offset) {
-  return &READ_FIELD(obj, byte_offset);
+  return reinterpret_cast<Object**>(FIELD_ADDR(obj, byte_offset));
 }
 
 
-int Smi::value() {
+int Smi::value() const {
   return Internals::SmiValue(this);
 }
 
@@ -1281,7 +1284,7 @@ bool Smi::IsValid(intptr_t value) {
 }
 
 
-MapWord MapWord::FromMap(Map* map) {
+MapWord MapWord::FromMap(const Map* map) {
   return MapWord(reinterpret_cast<uintptr_t>(map));
 }
 
@@ -1319,9 +1322,9 @@ void HeapObject::VerifySmiField(int offset) {
 #endif
 
 
-Heap* HeapObject::GetHeap() {
+Heap* HeapObject::GetHeap() const {
   Heap* heap =
-      MemoryChunk::FromAddress(reinterpret_cast<Address>(this))->heap();
+      MemoryChunk::FromAddress(reinterpret_cast<const byte*>(this))->heap();
   SLOW_ASSERT(heap != NULL);
   return heap;
 }
@@ -1332,7 +1335,7 @@ Isolate* HeapObject::GetIsolate() {
 }
 
 
-Map* HeapObject::map() {
+Map* HeapObject::map() const {
 #ifdef DEBUG
   // Clear mark potentially added by PathTracer.
   uintptr_t raw_value =
@@ -1380,7 +1383,7 @@ void HeapObject::set_map_no_write_barrier(Map* value) {
 }
 
 
-MapWord HeapObject::map_word() {
+MapWord HeapObject::map_word() const {
   return MapWord(
       reinterpret_cast<uintptr_t>(NOBARRIER_READ_FIELD(this, kMapOffset)));
 }
@@ -1392,7 +1395,7 @@ void HeapObject::set_map_word(MapWord map_word) {
 }
 
 
-MapWord HeapObject::synchronized_map_word() {
+MapWord HeapObject::synchronized_map_word() const {
   return MapWord(
       reinterpret_cast<uintptr_t>(ACQUIRE_READ_FIELD(this, kMapOffset)));
 }
@@ -1476,7 +1479,7 @@ bool FixedArray::ContainsOnlySmisOrHoles() {
 }
 
 
-FixedArrayBase* JSObject::elements() {
+FixedArrayBase* JSObject::elements() const {
   Object* array = READ_FIELD(this, kElementsOffset);
   return static_cast<FixedArrayBase*>(array);
 }
@@ -1817,7 +1820,7 @@ void Oddball::set_kind(byte value) {
 }
 
 
-Object* Cell::value() {
+Object* Cell::value() const {
   return READ_FIELD(this, kValueOffset);
 }
 
@@ -1830,7 +1833,7 @@ void Cell::set_value(Object* val, WriteBarrierMode ignored) {
 
 ACCESSORS(PropertyCell, dependent_code, DependentCode, kDependentCodeOffset)
 
-Object* PropertyCell::type_raw() {
+Object* PropertyCell::type_raw() const {
   return READ_FIELD(this, kTypeOffset);
 }
 
@@ -3645,7 +3648,7 @@ void ExternalUint8ClampedArray::set(int index, uint8_t value) {
 }
 
 
-void* ExternalArray::external_pointer() {
+void* ExternalArray::external_pointer() const {
   intptr_t ptr = READ_INTPTR_FIELD(this, kExternalPointerOffset);
   return reinterpret_cast<void*>(ptr);
 }
@@ -4885,7 +4888,7 @@ bool Code::IsWeakObjectInIC(Object* object) {
 }
 
 
-Object* Map::prototype() {
+Object* Map::prototype() const {
   return READ_FIELD(this, kPrototypeOffset);
 }
 
@@ -4961,7 +4964,7 @@ bool Map::HasElementsTransition() {
 }
 
 
-bool Map::HasTransitionArray() {
+bool Map::HasTransitionArray() const {
   Object* object = READ_FIELD(this, kTransitionsOrBackPointerOffset);
   return object->IsTransitionArray();
 }
@@ -5021,7 +5024,7 @@ bool Map::HasPrototypeTransitions() {
 }
 
 
-TransitionArray* Map::transitions() {
+TransitionArray* Map::transitions() const {
   ASSERT(HasTransitionArray());
   Object* object = READ_FIELD(this, kTransitionsOrBackPointerOffset);
   return TransitionArray::cast(object);
@@ -5286,7 +5289,7 @@ SMI_ACCESSORS(SharedFunctionInfo, profiler_ticks, kProfilerTicksOffset)
 
 #define PSEUDO_SMI_ACCESSORS_LO(holder, name, offset)             \
   STATIC_ASSERT(holder::offset % kPointerSize == 0);              \
-  int holder::name() {                                            \
+  int holder::name() const {                                      \
     int value = READ_INT_FIELD(this, offset);                     \
     ASSERT(kHeapObjectTag == 1);                                  \
     ASSERT((value & kHeapObjectTag) == 0);                        \
@@ -5428,7 +5431,7 @@ void SharedFunctionInfo::set_start_position(int start_position) {
 }
 
 
-Code* SharedFunctionInfo::code() {
+Code* SharedFunctionInfo::code() const {
   return Code::cast(READ_FIELD(this, kCodeOffset));
 }
 
@@ -5454,7 +5457,7 @@ void SharedFunctionInfo::ReplaceCode(Code* value) {
 }
 
 
-ScopeInfo* SharedFunctionInfo::scope_info() {
+ScopeInfo* SharedFunctionInfo::scope_info() const {
   return reinterpret_cast<ScopeInfo*>(READ_FIELD(this, kScopeInfoOffset));
 }
 
@@ -5826,7 +5829,7 @@ ACCESSORS(JSMap, table, Object, kTableOffset)
 
 #define ORDERED_HASH_TABLE_ITERATOR_ACCESSORS(name, type, offset)    \
   template<class Derived, class TableType>                           \
-  type* OrderedHashTableIterator<Derived, TableType>::name() {       \
+  type* OrderedHashTableIterator<Derived, TableType>::name() const { \
     return type::cast(READ_FIELD(this, offset));                     \
   }                                                                  \
   template<class Derived, class TableType>                           \
@@ -6042,7 +6045,7 @@ bool Code::contains(byte* inner_pointer) {
 ACCESSORS(JSArray, length, Object, kLengthOffset)
 
 
-void* JSArrayBuffer::backing_store() {
+void* JSArrayBuffer::backing_store() const {
   intptr_t ptr = READ_INTPTR_FIELD(this, kBackingStoreOffset);
   return reinterpret_cast<void*>(ptr);
 }
@@ -6972,6 +6975,7 @@ void FlexibleBodyDescriptor<start_offset>::IterateBody(HeapObject* obj,
 #undef BOOL_GETTER
 #undef BOOL_ACCESSORS
 #undef FIELD_ADDR
+#undef FIELD_ADDR_CONST
 #undef READ_FIELD
 #undef NOBARRIER_READ_FIELD
 #undef WRITE_FIELD

src/objects.h

@@ -845,12 +845,12 @@ enum CompareResult {
 
 
 #define DECL_BOOLEAN_ACCESSORS(name)   \
-  inline bool name();                  \
+  inline bool name() const;            \
   inline void set_##name(bool value);  \
 
 
 #define DECL_ACCESSORS(name, type)                                      \
-  inline type* name();                                                  \
+  inline type* name() const;                                            \
   inline void set_##name(type* value,                                   \
                          WriteBarrierMode mode = UPDATE_WRITE_BARRIER); \
 
@@ -1574,7 +1574,7 @@ class Object {
 class Smi: public Object {
  public:
   // Returns the integer value.
-  inline int value();
+  inline int value() const;
 
   // Convert a value to a Smi object.
   static inline Smi* FromInt(int value);
@@ -1611,7 +1611,7 @@ class MapWord BASE_EMBEDDED {
   // Normal state: the map word contains a map pointer.
 
   // Create a map word from a map pointer.
-  static inline MapWord FromMap(Map* map);
+  static inline MapWord FromMap(const Map* map);
 
   // View this map word as a map pointer.
   inline Map* ToMap();
@@ -1655,7 +1655,7 @@ class HeapObject: public Object {
  public:
   // [map]: Contains a map which contains the object's reflective
   // information.
-  inline Map* map();
+  inline Map* map() const;
   inline void set_map(Map* value);
   // The no-write-barrier version.  This is OK if the object is white and in
   // new space, or if the value is an immortal immutable object, like the maps
@@ -1664,7 +1664,7 @@ class HeapObject: public Object {
 
   // Get the map using acquire load.
   inline Map* synchronized_map();
-  inline MapWord synchronized_map_word();
+  inline MapWord synchronized_map_word() const;
 
   // Set the map using release store
   inline void synchronized_set_map(Map* value);
@@ -1673,11 +1673,11 @@ class HeapObject: public Object {
 
   // During garbage collection, the map word of a heap object does not
   // necessarily contain a map pointer.
-  inline MapWord map_word();
+  inline MapWord map_word() const;
   inline void set_map_word(MapWord map_word);
 
   // The Heap the object was allocated in. Used also to access Isolate.
-  inline Heap* GetHeap();
+  inline Heap* GetHeap() const;
 
   // Convenience method to get current isolate.
   inline Isolate* GetIsolate();
@@ -2868,11 +2868,11 @@ class JSObject: public JSReceiver {
 class FixedArrayBase: public HeapObject {
  public:
   // [length]: length of the array.
-  inline int length();
+  inline int length() const;
   inline void set_length(int value);
 
   // Get and set the length using acquire loads and release stores.
-  inline int synchronized_length();
+  inline int synchronized_length() const;
   inline void synchronized_set_length(int value);
 
   inline static FixedArrayBase* cast(Object* object);
@@ -4891,10 +4891,10 @@ class ByteArray: public FixedArrayBase {
 class FreeSpace: public HeapObject {
  public:
   // [size]: size of the free space including the header.
-  inline int size();
+  inline int size() const;
   inline void set_size(int value);
 
-  inline int nobarrier_size();
+  inline int nobarrier_size() const;
   inline void nobarrier_set_size(int value);
 
   inline int Size() { return size(); }
@@ -5485,7 +5485,7 @@ class Code: public HeapObject {
 #endif  // ENABLE_DISASSEMBLER
 
   // [instruction_size]: Size of the native instructions
-  inline int instruction_size();
+  inline int instruction_size() const;
   inline void set_instruction_size(int value);
 
   // [relocation_info]: Code relocation information
@@ -5522,11 +5522,11 @@ class Code: public HeapObject {
   // [ic_age]: Inline caching age: the value of the Heap::global_ic_age
   // at the moment when this object was created.
   inline void set_ic_age(int count);
-  inline int ic_age();
+  inline int ic_age() const;
 
   // [prologue_offset]: Offset of the function prologue, used for aging
   // FUNCTIONs and OPTIMIZED_FUNCTIONs.
-  inline int prologue_offset();
+  inline int prologue_offset() const;
   inline void set_prologue_offset(int offset);
 
   // Unchecked accessors to be used during GC.
@@ -6287,7 +6287,7 @@ class Map: public HeapObject {
   // map with DICTIONARY_ELEMENTS was found in the prototype chain.
   bool DictionaryElementsInPrototypeChainOnly();
 
-  inline bool HasTransitionArray();
+  inline bool HasTransitionArray() const;
   inline bool HasElementsTransition();
   inline Map* elements_transition_map();
   static Handle<TransitionArray> SetElementsTransitionMap(
@@ -7106,11 +7106,11 @@ class SharedFunctionInfo: public HeapObject {
 
   // [length]: The function length - usually the number of declared parameters.
   // Use up to 2^30 parameters.
-  inline int length();
+  inline int length() const;
   inline void set_length(int value);
 
   // [formal parameter count]: The declared number of parameters.
-  inline int formal_parameter_count();
+  inline int formal_parameter_count() const;
   inline void set_formal_parameter_count(int value);
 
   // Set the formal parameter count so the function code will be
@@ -7118,7 +7118,7 @@ class SharedFunctionInfo: public HeapObject {
   inline void DontAdaptArguments();
 
   // [expected_nof_properties]: Expected number of properties for the function.
-  inline int expected_nof_properties();
+  inline int expected_nof_properties() const;
   inline void set_expected_nof_properties(int value);
 
   // [feedback_vector] - accumulates ast node feedback from full-codegen and
@@ -7147,7 +7147,7 @@ class SharedFunctionInfo: public HeapObject {
   DECL_ACCESSORS(script, Object)
 
   // [num_literals]: Number of literals used by this function.
-  inline int num_literals();
+  inline int num_literals() const;
   inline void set_num_literals(int value);
 
   // [start_position_and_type]: Field used to store both the source code
@@ -7155,7 +7155,7 @@ class SharedFunctionInfo: public HeapObject {
   // and whether or not the function is a toplevel function. The two
   // least significants bit indicates whether the function is an
   // expression and the rest contains the source code position.
-  inline int start_position_and_type();
+  inline int start_position_and_type() const;
   inline void set_start_position_and_type(int value);
 
   // [debug info]: Debug information.
@@ -7172,7 +7172,7 @@ class SharedFunctionInfo: public HeapObject {
   String* DebugName();
 
   // Position of the 'function' token in the script source.
-  inline int function_token_position();
+  inline int function_token_position() const;
   inline void set_function_token_position(int function_token_position);
 
   // Position of this function in the script source.
@@ -7180,7 +7180,7 @@ class SharedFunctionInfo: public HeapObject {
   inline void set_start_position(int start_position);
 
   // End position of this function in the script source.
-  inline int end_position();
+  inline int end_position() const;
   inline void set_end_position(int end_position);
 
   // Is this function a function expression in the source code.
@@ -7191,13 +7191,13 @@ class SharedFunctionInfo: public HeapObject {
 
   // Bit field containing various information collected by the compiler to
   // drive optimization.
-  inline int compiler_hints();
+  inline int compiler_hints() const;
   inline void set_compiler_hints(int value);
 
-  inline int ast_node_count();
+  inline int ast_node_count() const;
   inline void set_ast_node_count(int count);
 
-  inline int profiler_ticks();
+  inline int profiler_ticks() const;
   inline void set_profiler_ticks(int ticks);
 
   // Inline cache age is used to infer whether the function survived a context
@@ -7313,11 +7313,11 @@ class SharedFunctionInfo: public HeapObject {
 
   // Stores deopt_count, opt_reenable_tries and ic_age as bit-fields.
   inline void set_counters(int value);
-  inline int counters();
+  inline int counters() const;
 
   // Stores opt_count and bailout_reason as bit-fields.
   inline void set_opt_count_and_bailout_reason(int value);
-  inline int opt_count_and_bailout_reason();
+  inline int opt_count_and_bailout_reason() const;
 
   void set_bailout_reason(BailoutReason reason) {
     set_opt_count_and_bailout_reason(
@@ -7549,7 +7549,7 @@ class JSGeneratorObject: public JSObject {
   // A positive offset indicates a suspended generator.  The special
   // kGeneratorExecuting and kGeneratorClosed values indicate that a generator
   // cannot be resumed.
-  inline int continuation();
+  inline int continuation() const;
   inline void set_continuation(int continuation);
   inline bool is_closed();
   inline bool is_executing();
@@ -7560,7 +7560,7 @@ class JSGeneratorObject: public JSObject {
 
   // [stack_handler_index]: Index of first stack handler in operand_stack, or -1
   // if the captured activation had no stack handler.
-  inline int stack_handler_index();
+  inline int stack_handler_index() const;
   inline void set_stack_handler_index(int stack_handler_index);
 
   // Casting.
@@ -8121,11 +8121,11 @@ class JSMessageObject: public JSObject {
   DECL_ACCESSORS(stack_frames, Object)
 
   // [start_position]: the start position in the script for the error message.
-  inline int start_position();
+  inline int start_position() const;
   inline void set_start_position(int value);
 
   // [end_position]: the end position in the script for the error message.
-  inline int end_position();
+  inline int end_position() const;
   inline void set_end_position(int value);
 
   // Casting.
@@ -8779,7 +8779,7 @@ class AllocationMemento: public Struct {
 // - all attributes are available as part if the property details
 class AliasedArgumentsEntry: public Struct {
  public:
-  inline int aliased_context_slot();
+  inline int aliased_context_slot() const;
   inline void set_aliased_context_slot(int count);
 
   static inline AliasedArgumentsEntry* cast(Object* obj);
@@ -9116,12 +9116,12 @@ class String: public Name {
   };
 
   // Get and set the length of the string.
-  inline int length();
+  inline int length() const;
   inline void set_length(int value);
 
   // Get and set the length of the string using acquire loads and release
   // stores.
-  inline int synchronized_length();
+  inline int synchronized_length() const;
   inline void synchronized_set_length(int value);
 
   // Returns whether this string has only ASCII chars, i.e. all of them can
@@ -9519,7 +9519,7 @@ class SlicedString: public String {
   inline String* parent();
   inline void set_parent(String* parent,
                          WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
-  inline int offset();
+  inline int offset() const;
   inline void set_offset(int offset);
 
   // Dispatched behavior.
@@ -10901,7 +10901,7 @@ class FunctionTemplateInfo: public TemplateInfo {
   DECL_ACCESSORS(access_check_info, Object)
   DECL_ACCESSORS(flag, Smi)
 
-  inline int length();
+  inline int length() const;
   inline void set_length(int value);
 
   // Following properties use flag bits.

src/spaces.h

@@ -283,6 +283,10 @@ class MemoryChunk {
   static MemoryChunk* FromAddress(Address a) {
     return reinterpret_cast<MemoryChunk*>(OffsetFrom(a) & ~kAlignmentMask);
   }
+  static const MemoryChunk* FromAddress(const byte* a) {
+    return reinterpret_cast<const MemoryChunk*>(
+        OffsetFrom(a) & ~kAlignmentMask);
+  }
 
   // Only works for addresses in pointer spaces, not data or code spaces.
   static inline MemoryChunk* FromAnyPointerAddress(Heap* heap, Address addr);
@@ -627,7 +631,7 @@ class MemoryChunk {
   void InsertAfter(MemoryChunk* other);
   void Unlink();
 
-  inline Heap* heap() { return heap_; }
+  inline Heap* heap() const { return heap_; }
 
   static const int kFlagsOffset = kPointerSize;