Add mark compact collector.
The mark compact collector is a 4 phase collection, doing a normal
full mark_sweep, calculating forwarding addresses of objects in the
from space, updating references of objects in the from space, and
moving the objects in the from space.
Support is diabled by default since it needs to have non movable
classes and field arrays. Performance numbers is around 50% as fast.
The main advantage that this has over semispace is that the worst
case memory usage is 50% since we only need one space isntead of two.
TODO: Make field arrays and classes movable. This causes complication
since Object::VisitReferences relies on these, so if we update the
fields of an object but another future object uses this object to
figure out what fields are reference fields it doesn't work.
Bug: 14059466
Change-Id: I661ed3b71ad4dde124ef80312c95696b4a5665a1
diff --git a/runtime/class_linker-inl.h b/runtime/class_linker-inl.h
index f745088..16e0ec3 100644
--- a/runtime/class_linker-inl.h
+++ b/runtime/class_linker-inl.h
@@ -18,6 +18,7 @@
#define ART_RUNTIME_CLASS_LINKER_INL_H_
#include "class_linker.h"
+#include "gc/heap-inl.h"
#include "mirror/art_field.h"
#include "mirror/class_loader.h"
#include "mirror/dex_cache-inl.h"
@@ -186,13 +187,19 @@
inline mirror::IfTable* ClassLinker::AllocIfTable(Thread* self, size_t ifcount) {
return down_cast<mirror::IfTable*>(
- mirror::IfTable::Alloc(self, GetClassRoot(kObjectArrayClass), ifcount * mirror::IfTable::kMax));
+ mirror::IfTable::Alloc(self, GetClassRoot(kObjectArrayClass),
+ ifcount * mirror::IfTable::kMax));
}
inline mirror::ObjectArray<mirror::ArtField>* ClassLinker::AllocArtFieldArray(Thread* self,
size_t length) {
+ gc::Heap* const heap = Runtime::Current()->GetHeap();
+ // Can't have movable field arrays for mark compact since we need these arrays to always be valid
+ // so that we can do Object::VisitReferences in the case where the fields don't fit in the
+ // reference offsets word.
return mirror::ObjectArray<mirror::ArtField>::Alloc(
- self, GetClassRoot(kJavaLangReflectArtFieldArrayClass), length);
+ self, GetClassRoot(kJavaLangReflectArtFieldArrayClass), length,
+ kMoveFieldArrays ? heap->GetCurrentAllocator() : heap->GetCurrentNonMovingAllocator());
}
inline mirror::Class* ClassLinker::GetClassRoot(ClassRoot class_root)