x86/x86-64 read barrier support for concurrent GC in Optimizing.
This first implementation uses slow paths to instrument heap
reference loads and GC root loads for the concurrent copying
collector, respectively calling the artReadBarrierSlow and
artReadBarrierForRootSlow (new) runtime entry points.
Notes:
- This implementation does not instrument HInvokeVirtual
nor HInvokeInterface instructions (for class reference
loads), as the corresponding read barriers are not stricly
required with the current concurrent copying collector.
- Intrinsics which may eventually call (on slow path) are
disabled when read barriers are enabled, as the current
slow path infrastructure does not support this case.
- When read barriers are enabled, the code generated for a
HArraySet instruction always go into the array set slow
path for object arrays (delegating the operation to the
runtime), as we are lacking a mechanism to keep a
temporary register live accross a runtime call (needed for
the instrumentation of type checking code, which requires
two successive read barriers).
Bug: 12687968
Change-Id: I14cd6107233c326389120336f93955b28ffbb329
diff --git a/runtime/mirror/array.h b/runtime/mirror/array.h
index b27a884..7458424 100644
--- a/runtime/mirror/array.h
+++ b/runtime/mirror/array.h
@@ -122,7 +122,7 @@
T Get(int32_t i) ALWAYS_INLINE SHARED_REQUIRES(Locks::mutator_lock_);
T GetWithoutChecks(int32_t i) ALWAYS_INLINE SHARED_REQUIRES(Locks::mutator_lock_) {
- DCHECK(CheckIsValidIndex(i));
+ DCHECK(CheckIsValidIndex(i)) << "i=" << i << " length=" << GetLength();
return GetData()[i];
}
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index c4339b9..80e136c 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -1185,7 +1185,7 @@
bool ProxyDescriptorEquals(const char* match) SHARED_REQUIRES(Locks::mutator_lock_);
- // Check that the pointer size mathces the one in the class linker.
+ // Check that the pointer size matches the one in the class linker.
ALWAYS_INLINE static void CheckPointerSize(size_t pointer_size);
static MemberOffset EmbeddedImTableOffset(size_t pointer_size);
diff --git a/runtime/mirror/string.h b/runtime/mirror/string.h
index fbee2d7..80ebd2c 100644
--- a/runtime/mirror/string.h
+++ b/runtime/mirror/string.h
@@ -27,6 +27,7 @@
template<class T> class Handle;
struct StringOffsets;
class StringPiece;
+class StubTest_ReadBarrierForRoot_Test;
namespace mirror {
@@ -179,7 +180,7 @@
static GcRoot<Class> java_lang_String_;
friend struct art::StringOffsets; // for verifying offset information
- ART_FRIEND_TEST(ObjectTest, StringLength); // for SetOffset and SetCount
+ ART_FRIEND_TEST(art::StubTest, ReadBarrierForRoot); // For java_lang_String_.
DISALLOW_IMPLICIT_CONSTRUCTORS(String);
};