Elide write barriers and remove some heap_object->GetHeap() calls on

src/objects-inl.h

 // Copyright 2011 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 72 matching lines @@
 
 #define INT_ACCESSORS(holder, name, offset)                             \
   int holder::name() { 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);    \
+    CONDITIONAL_WRITE_BARRIER(this, offset, value, mode);               \
   }
 
 
 #define SMI_ACCESSORS(holder, name, offset)             \
   int holder::name() {                                  \
     Object* value = READ_FIELD(this, offset);           \
     return Smi::cast(value)->value();                   \
   }                                                     \
   void holder::set_##name(int value) {                  \
     WRITE_FIELD(this, offset, Smi::FromInt(value));     \
@@ skipping 735 matching lines @@
 
 #define FIELD_ADDR(p, offset) \
   (reinterpret_cast<byte*>(p) + offset - kHeapObjectTag)
 
 #define READ_FIELD(p, offset) \
   (*reinterpret_cast<Object**>(FIELD_ADDR(p, offset)))
 
 #define WRITE_FIELD(p, offset, value) \
   (*reinterpret_cast<Object**>(FIELD_ADDR(p, offset)) = value)
 
-#define WRITE_BARRIER(heap, object, offset, value)                      \
-  heap->incremental_marking()->RecordWrite(                             \
-      object, HeapObject::RawField(object, offset), value);             \
-  if (heap->InNewSpace(value)) {                                        \
-    heap->RecordWrite(object->address(), offset);                       \
+#define WRITE_BARRIER(object, offset, value)                            \
+  Address value_addr = reinterpret_cast<HeapObject*>(value)->address(); \
+  if (!value->IsSmi() && Page::FromAddress(value_addr)->IsFlagSet(      \
+        MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING)) {               \
+    Heap* heap = object->GetHeap();                                     \
+    heap->incremental_marking()->RecordWrite(                           \
+        object, HeapObject::RawField(object, offset), value);           \
+    if (heap->InNewSpace(value)) {                                      \
+      heap->RecordWrite(object->address(), offset);                     \
+    }                                                                   \
   }
 
-#define CONDITIONAL_WRITE_BARRIER(heap, object, offset, value, mode)    \
-  if (mode == UPDATE_WRITE_BARRIER) {                                   \
+#define CONDITIONAL_WRITE_BARRIER(object, offset, value, mode)          \
+  Address value_addr = reinterpret_cast<HeapObject*>(value)->address(); \
+  if (mode == UPDATE_WRITE_BARRIER &&                                   \
+      !value->IsSmi() &&                                                \
+      Page::FromAddress(value_addr)->IsFlagSet(                         \
+          MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING)) {             \
+    Heap* heap = object->GetHeap();                                     \
     heap->incremental_marking()->RecordWrite(                           \
       object, HeapObject::RawField(object, offset), value);             \
     if (heap->InNewSpace(value)) {                                      \
       heap->RecordWrite(object->address(), offset);                     \
     }                                                                   \
   }
 
+#define CONDITIONAL_WRITE_BARRIER_WITH_HEAP(heap, object, offset, value, mode) \
+  if (mode == UPDATE_WRITE_BARRIER) {                                          \
+    heap->incremental_marking()->RecordWrite(                                  \
+      object, HeapObject::RawField(object, offset), value);                    \
+    if (heap->InNewSpace(value)) {                                             \
+      heap->RecordWrite(object->address(), offset);                            \
+    }                                                                          \
+  }
+
 #ifndef V8_TARGET_ARCH_MIPS
   #define READ_DOUBLE_FIELD(p, offset) \
     (*reinterpret_cast<double*>(FIELD_ADDR(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) {
     union conversion {
       double d;
       uint32_t u[2];
@@ skipping 376 matching lines @@
           map()->has_fast_smi_only_elements()) ==
          (value->map() == GetHeap()->fixed_array_map() ||
           value->map() == GetHeap()->fixed_cow_array_map()));
   ASSERT(map()->has_fast_double_elements() ==
          value->IsFixedDoubleArray());
   ASSERT(value->HasValidElements());
 #ifdef DEBUG
   ValidateSmiOnlyElements();
 #endif
   WRITE_FIELD(this, kElementsOffset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, kElementsOffset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, kElementsOffset, value, mode);
 }
 
 
 void JSObject::initialize_properties() {
   ASSERT(!GetHeap()->InNewSpace(GetHeap()->empty_fixed_array()));
   WRITE_FIELD(this, kPropertiesOffset, GetHeap()->empty_fixed_array());
 }
 
 
 void JSObject::initialize_elements() {
@@ skipping 102 matching lines @@
 }
 
 
 void JSObject::SetInternalField(int index, Object* value) {
   ASSERT(index < GetInternalFieldCount() && index >= 0);
   // Internal objects do follow immediately after the header, whereas in-object
   // properties are at the end of the object. Therefore there is no need
   // to adjust the index here.
   int offset = GetHeaderSize() + (kPointerSize * index);
   WRITE_FIELD(this, offset, value);
-  WRITE_BARRIER(GetHeap(), this, offset, value);
+  WRITE_BARRIER(this, offset, value);
 }
 
 
 void JSObject::SetInternalField(int index, Smi* value) {
   ASSERT(index < GetInternalFieldCount() && index >= 0);
   // Internal objects do follow immediately after the header, whereas in-object
   // properties are at the end of the object. Therefore there is no need
   // to adjust the index here.
   int offset = GetHeaderSize() + (kPointerSize * index);
   WRITE_FIELD(this, offset, value);
@@ skipping 15 matching lines @@
   }
 }
 
 
 Object* JSObject::FastPropertyAtPut(int index, Object* value) {
   // Adjust for the number of properties stored in the object.
   index -= map()->inobject_properties();
   if (index < 0) {
     int offset = map()->instance_size() + (index * kPointerSize);
     WRITE_FIELD(this, offset, value);
-    WRITE_BARRIER(GetHeap(), this, offset, value);
+    WRITE_BARRIER(this, offset, value);
   } else {
     ASSERT(index < properties()->length());
     properties()->set(index, value);
   }
   return value;
 }
 
 
 int JSObject::GetInObjectPropertyOffset(int index) {
   // Adjust for the number of properties stored in the object.
@@ skipping 13 matching lines @@
 
 
 Object* JSObject::InObjectPropertyAtPut(int index,
                                         Object* value,
                                         WriteBarrierMode mode) {
   // Adjust for the number of properties stored in the object.
   index -= map()->inobject_properties();
   ASSERT(index < 0);
   int offset = map()->instance_size() + (index * kPointerSize);
   WRITE_FIELD(this, offset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, offset, value, mode);
   return value;
 }
 
 
 
 void JSObject::InitializeBody(Map* map,
                               Object* pre_allocated_value,
                               Object* filler_value) {
   ASSERT(!filler_value->IsHeapObject() ||
          !GetHeap()->InNewSpace(filler_value));
@@ skipping 90 matching lines @@
   int offset = kHeaderSize + index * kPointerSize;
   WRITE_FIELD(this, offset, value);
 }
 
 
 void FixedArray::set(int index, Object* value) {
   ASSERT(map() != HEAP->fixed_cow_array_map());
   ASSERT(index >= 0 && index < this->length());
   int offset = kHeaderSize + index * kPointerSize;
   WRITE_FIELD(this, offset, value);
-  WRITE_BARRIER(GetHeap(), this, offset, value);
+  WRITE_BARRIER(this, offset, value);
 }
 
 
 inline bool FixedDoubleArray::is_the_hole_nan(double value) {
   return BitCast<uint64_t, double>(value) == kHoleNanInt64;
 }
 
 
 inline double FixedDoubleArray::hole_nan_as_double() {
   return BitCast<double, uint64_t>(kHoleNanInt64);
@@ skipping 116 matching lines @@
 }
 
 
 void FixedArray::set(int index,
                      Object* value,
                      WriteBarrierMode mode) {
   ASSERT(map() != HEAP->fixed_cow_array_map());
   ASSERT(index >= 0 && index < this->length());
   int offset = kHeaderSize + index * kPointerSize;
   WRITE_FIELD(this, offset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, offset, value, mode);
 }
 
 
 void FixedArray::NoWriteBarrierSet(FixedArray* array,
                                    int index,
                                    Object* value) {
   ASSERT(array->map() != HEAP->raw_unchecked_fixed_cow_array_map());
   ASSERT(index >= 0 && index < array->length());
   ASSERT(!HEAP->InNewSpace(value));
   WRITE_FIELD(array, kHeaderSize + index * kPointerSize, value);
@@ skipping 42 matching lines @@
   WRITE_FIELD(this, offset, value);
 }
 
 
 void FixedArray::set_unchecked(Heap* heap,
                                int index,
                                Object* value,
                                WriteBarrierMode mode) {
   int offset = kHeaderSize + index * kPointerSize;
   WRITE_FIELD(this, offset, value);
-  CONDITIONAL_WRITE_BARRIER(heap, this, offset, value, mode);
+  CONDITIONAL_WRITE_BARRIER_WITH_HEAP(heap, this, offset, value, mode);
 }
 
 
 void FixedArray::set_null_unchecked(Heap* heap, int index) {
   ASSERT(index >= 0 && index < this->length());
   ASSERT(!HEAP->InNewSpace(heap->null_value()));
   WRITE_FIELD(this, kHeaderSize + index * kPointerSize, heap->null_value());
 }
 
 
@@ skipping 494 matching lines @@
 }
 
 
 Object* ConsString::unchecked_first() {
   return READ_FIELD(this, kFirstOffset);
 }
 
 
 void ConsString::set_first(String* value, WriteBarrierMode mode) {
   WRITE_FIELD(this, kFirstOffset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, kFirstOffset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, kFirstOffset, value, mode);
 }
 
 
 String* ConsString::second() {
   return String::cast(READ_FIELD(this, kSecondOffset));
 }
 
 
 Object* ConsString::unchecked_second() {
   return READ_FIELD(this, kSecondOffset);
 }
 
 
 void ConsString::set_second(String* value, WriteBarrierMode mode) {
   WRITE_FIELD(this, kSecondOffset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, kSecondOffset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, kSecondOffset, value, mode);
 }
 
 
 bool ExternalString::is_short() {
   InstanceType type = map()->instance_type();
   return (type & kShortExternalStringMask) == kShortExternalStringTag;
 }
 
 
 const ExternalAsciiString::Resource* ExternalAsciiString::resource() {
@@ skipping 895 matching lines @@
 
 
 Object* Map::prototype() {
   return READ_FIELD(this, kPrototypeOffset);
 }
 
 
 void Map::set_prototype(Object* value, WriteBarrierMode mode) {
   ASSERT(value->IsNull() || value->IsJSReceiver());
   WRITE_FIELD(this, kPrototypeOffset, value);
-  CONDITIONAL_WRITE_BARRIER(GetHeap(), this, kPrototypeOffset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, kPrototypeOffset, value, mode);
 }
 
 
 DescriptorArray* Map::instance_descriptors() {
   Object* object = READ_FIELD(this, kInstanceDescriptorsOrBitField3Offset);
   if (object->IsSmi()) {
     return HEAP->empty_descriptor_array();
   } else {
     return DescriptorArray::cast(object);
   }
@@ skipping 28 matching lines @@
   } else {
     if (object->IsSmi()) {
       value->set_bit_field3_storage(Smi::cast(object)->value());
     } else {
       value->set_bit_field3_storage(
           DescriptorArray::cast(object)->bit_field3_storage());
     }
   }
   ASSERT(!is_shared());
   WRITE_FIELD(this, kInstanceDescriptorsOrBitField3Offset, value);
-  CONDITIONAL_WRITE_BARRIER(
+  CONDITIONAL_WRITE_BARRIER_WITH_HEAP(
       heap, this, kInstanceDescriptorsOrBitField3Offset, value, mode);
 }
 
 
 int Map::bit_field3() {
   Object* object = READ_FIELD(this,
                               kInstanceDescriptorsOrBitField3Offset);
   if (object->IsSmi()) {
     return Smi::cast(object)->value();
   } else {
@@ skipping 351 matching lines @@
 }
 
 
 Code* SharedFunctionInfo::unchecked_code() {
   return reinterpret_cast<Code*>(READ_FIELD(this, kCodeOffset));
 }
 
 
 void SharedFunctionInfo::set_code(Code* value, WriteBarrierMode mode) {
   WRITE_FIELD(this, kCodeOffset, value);
-  CONDITIONAL_WRITE_BARRIER(value->GetHeap(), this, kCodeOffset, value, mode);
+  CONDITIONAL_WRITE_BARRIER(this, kCodeOffset, value, mode);
 }
 
 
 ScopeInfo* SharedFunctionInfo::scope_info() {
   return reinterpret_cast<ScopeInfo*>(READ_FIELD(this, kScopeInfoOffset));
 }
 
 
 void SharedFunctionInfo::set_scope_info(ScopeInfo* value,
                                         WriteBarrierMode mode) {
   WRITE_FIELD(this, kScopeInfoOffset, reinterpret_cast<Object*>(value));
-  CONDITIONAL_WRITE_BARRIER(GetHeap(),
-                            this,
+  CONDITIONAL_WRITE_BARRIER(this,
                             kScopeInfoOffset,
                             reinterpret_cast<Object*>(value),
                             mode);
 }
 
 
 Smi* SharedFunctionInfo::deopt_counter() {
   return reinterpret_cast<Smi*>(READ_FIELD(this, kDeoptCounterOffset));
 }
 
@@ skipping 125 matching lines @@
 
 SharedFunctionInfo* JSFunction::unchecked_shared() {
   return reinterpret_cast<SharedFunctionInfo*>(
       READ_FIELD(this, kSharedFunctionInfoOffset));
 }
 
 
 void JSFunction::set_context(Object* value) {
   ASSERT(value->IsUndefined() || value->IsContext());
   WRITE_FIELD(this, kContextOffset, value);
-  WRITE_BARRIER(GetHeap(), this, kContextOffset, value);
+  WRITE_BARRIER(this, kContextOffset, value);
 }
 
 ACCESSORS(JSFunction, prototype_or_initial_map, Object,
           kPrototypeOrInitialMapOffset)
 
 
 Map* JSFunction::initial_map() {
   return Map::cast(prototype_or_initial_map());
 }
 
@@ skipping 82 matching lines @@
 Object* JSBuiltinsObject::javascript_builtin(Builtins::JavaScript id) {
   ASSERT(id < kJSBuiltinsCount);  // id is unsigned.
   return READ_FIELD(this, OffsetOfFunctionWithId(id));
 }
 
 
 void JSBuiltinsObject::set_javascript_builtin(Builtins::JavaScript id,
                                               Object* value) {
   ASSERT(id < kJSBuiltinsCount);  // id is unsigned.
   WRITE_FIELD(this, OffsetOfFunctionWithId(id), value);
-  WRITE_BARRIER(GetHeap(), this, OffsetOfFunctionWithId(id), value);
+  WRITE_BARRIER(this, OffsetOfFunctionWithId(id), value);
 }
 
 
 Code* JSBuiltinsObject::javascript_builtin_code(Builtins::JavaScript id) {
   ASSERT(id < kJSBuiltinsCount);  // id is unsigned.
   return Code::cast(READ_FIELD(this, OffsetOfCodeWithId(id)));
 }
 
 
 void JSBuiltinsObject::set_javascript_builtin_code(Builtins::JavaScript id,
@@ skipping 785 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_