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Commit dae6e43d authored by ulan's avatar ulan Committed by Commit bot
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Fast body iteration for objects without unboxed fields. 

Currently BodyDescriptorBase::IterateBodyImpl does a run-time check
for obj->map()->HasFastPointerLayout(), which is redundant for all
non-JSObject heap objects.

BUG=chromium:694255

Review-Url: https://codereview.chromium.org/2774553003
Cr-Commit-Position: refs/heads/master@{#44111}
parent 885f0bc4
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Inline Side-by-side
Showing with 39 additions and 27 deletions
src/objects-body-descriptors-inl.h
View file @ dae6e43d
......@@ -17,7 +17,6 @@ int FlexibleBodyDescriptor<start_offset>::SizeOf(Map* map, HeapObject* object) {
return object->SizeFromMap(map);
}
bool BodyDescriptorBase::IsValidSlotImpl(HeapObject* obj, int offset) {
if (!FLAG_unbox_double_fields || obj->map()->HasFastPointerLayout()) {
return true;
......@@ -53,7 +52,6 @@ void BodyDescriptorBase::IterateBodyImpl(HeapObject* obj, int start_offset,
}
}
template <typename StaticVisitor>
void BodyDescriptorBase::IterateBodyImpl(Heap* heap, HeapObject* obj,
int start_offset, int end_offset) {
......@@ -76,39 +74,62 @@ void BodyDescriptorBase::IterateBodyImpl(Heap* heap, HeapObject* obj,
}
}
template <typename ObjectVisitor>
DISABLE_CFI_PERF
void BodyDescriptorBase::IteratePointers(HeapObject* obj, int start_offset,
int end_offset, ObjectVisitor* v) {
DISABLE_CFI_PERF void BodyDescriptorBase::IteratePointers(HeapObject* obj,
int start_offset,
int end_offset,
ObjectVisitor* v) {
v->VisitPointers(HeapObject::RawField(obj, start_offset),
HeapObject::RawField(obj, end_offset));
}
template <typename StaticVisitor>
DISABLE_CFI_PERF
void BodyDescriptorBase::IteratePointers(Heap* heap, HeapObject* obj,
int start_offset, int end_offset) {
DISABLE_CFI_PERF void BodyDescriptorBase::IteratePointers(Heap* heap,
HeapObject* obj,
int start_offset,
int end_offset) {
StaticVisitor::VisitPointers(heap, obj,
HeapObject::RawField(obj, start_offset),
HeapObject::RawField(obj, end_offset));
}
template <typename ObjectVisitor>
void BodyDescriptorBase::IteratePointer(HeapObject* obj, int offset,
ObjectVisitor* v) {
v->VisitPointer(HeapObject::RawField(obj, offset));
}
template <typename StaticVisitor>
void BodyDescriptorBase::IteratePointer(Heap* heap, HeapObject* obj,
int offset) {
StaticVisitor::VisitPointer(heap, obj, HeapObject::RawField(obj, offset));
}
class JSObject::BodyDescriptor final : public BodyDescriptorBase {
public:
static const int kStartOffset = JSReceiver::kPropertiesOffset;
static bool IsValidSlot(HeapObject* obj, int offset) {
if (offset < kStartOffset) return false;
return IsValidSlotImpl(obj, offset);
}
template <typename ObjectVisitor>
static inline void IterateBody(HeapObject* obj, int object_size,
ObjectVisitor* v) {
IterateBodyImpl(obj, kStartOffset, object_size, v);
}
template <typename StaticVisitor>
static inline void IterateBody(HeapObject* obj, int object_size) {
Heap* heap = obj->GetHeap();
IterateBodyImpl<StaticVisitor>(heap, obj, kStartOffset, object_size);
}
static inline int SizeOf(Map* map, HeapObject* object) {
return map->instance_size();
}
};
// Iterates the function object according to the visiting policy.
template <JSFunction::BodyVisitingPolicy body_visiting_policy>
......@@ -160,7 +181,6 @@ class JSFunction::BodyDescriptorImpl final : public BodyDescriptorBase {
}
};
class JSArrayBuffer::BodyDescriptor final : public BodyDescriptorBase {
public:
STATIC_ASSERT(kByteLengthOffset + kPointerSize == kBackingStoreOffset);
......@@ -193,7 +213,6 @@ class JSArrayBuffer::BodyDescriptor final : public BodyDescriptorBase {
}
};
class BytecodeArray::BodyDescriptor final : public BodyDescriptorBase {
public:
static bool IsValidSlot(HeapObject* obj, int offset) {
......@@ -222,7 +241,6 @@ class BytecodeArray::BodyDescriptor final : public BodyDescriptorBase {
}
};
class FixedTypedArrayBase::BodyDescriptor final : public BodyDescriptorBase {
public:
static bool IsValidSlot(HeapObject* obj, int offset) {
......@@ -246,7 +264,6 @@ class FixedTypedArrayBase::BodyDescriptor final : public BodyDescriptorBase {
}
};
template <JSWeakCollection::BodyVisitingPolicy body_visiting_policy>
class JSWeakCollection::BodyDescriptorImpl final : public BodyDescriptorBase {
public:
......@@ -285,7 +302,6 @@ class JSWeakCollection::BodyDescriptorImpl final : public BodyDescriptorBase {
}
};
class Foreign::BodyDescriptor final : public BodyDescriptorBase {
public:
static bool IsValidSlot(HeapObject* obj, int offset) { return false; }
......@@ -306,7 +322,6 @@ class Foreign::BodyDescriptor final : public BodyDescriptorBase {
static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
};
class ExternalOneByteString::BodyDescriptor final : public BodyDescriptorBase {
public:
static bool IsValidSlot(HeapObject* obj, int offset) { return false; }
......@@ -329,7 +344,6 @@ class ExternalOneByteString::BodyDescriptor final : public BodyDescriptorBase {
static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
};
class ExternalTwoByteString::BodyDescriptor final : public BodyDescriptorBase {
public:
static bool IsValidSlot(HeapObject* obj, int offset) { return false; }
......@@ -352,7 +366,6 @@ class ExternalTwoByteString::BodyDescriptor final : public BodyDescriptorBase {
static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
};
class Code::BodyDescriptor final : public BodyDescriptorBase {
public:
STATIC_ASSERT(kRelocationInfoOffset + kPointerSize == kHandlerTableOffset);
......
src/objects-body-descriptors.h
View file @ dae6e43d
......@@ -82,7 +82,7 @@ class FixedBodyDescriptor final : public BodyDescriptorBase {
template <typename ObjectVisitor>
static inline void IterateBody(HeapObject* obj, ObjectVisitor* v) {
IterateBodyImpl(obj, start_offset, end_offset, v);
IteratePointers(obj, start_offset, end_offset, v);
}
template <typename ObjectVisitor>
......@@ -94,7 +94,7 @@ class FixedBodyDescriptor final : public BodyDescriptorBase {
template <typename StaticVisitor>
static inline void IterateBody(HeapObject* obj) {
Heap* heap = obj->GetHeap();
IterateBodyImpl<StaticVisitor>(heap, obj, start_offset, end_offset);
IteratePointers<StaticVisitor>(heap, obj, start_offset, end_offset);
}
template <typename StaticVisitor>
......@@ -113,20 +113,19 @@ class FlexibleBodyDescriptor final : public BodyDescriptorBase {
static const int kStartOffset = start_offset;
static bool IsValidSlot(HeapObject* obj, int offset) {
if (offset < kStartOffset) return false;
return IsValidSlotImpl(obj, offset);
return (offset >= kStartOffset);
}
template <typename ObjectVisitor>
static inline void IterateBody(HeapObject* obj, int object_size,
ObjectVisitor* v) {
IterateBodyImpl(obj, start_offset, object_size, v);
IteratePointers(obj, start_offset, object_size, v);
}
template <typename StaticVisitor>
static inline void IterateBody(HeapObject* obj, int object_size) {
Heap* heap = obj->GetHeap();
IterateBodyImpl<StaticVisitor>(heap, obj, start_offset, object_size);
IteratePointers<StaticVisitor>(heap, obj, start_offset, object_size);
}
static inline int SizeOf(Map* map, HeapObject* object);
......
src/objects.h
View file @ dae6e43d
......@@ -2552,7 +2552,7 @@ class JSObject: public JSReceiver {
STATIC_ASSERT(kHeaderSize == Internals::kJSObjectHeaderSize);
typedef FlexibleBodyDescriptor<JSReceiver::kPropertiesOffset> BodyDescriptor;
class BodyDescriptor;
// Gets the number of currently used elements.
int GetFastElementsUsage();
......
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