Add support for changing roots through the root visitor callback.
Needed for copying collectors.
Change-Id: Icc4a342a57e0cfb79587edb02ef8c85e08808877
diff --git a/runtime/thread.cc b/runtime/thread.cc
index a454195..d7d4b1f 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -1012,9 +1012,10 @@
}
}
-static void MonitorExitVisitor(const mirror::Object* object, void* arg) NO_THREAD_SAFETY_ANALYSIS {
+static mirror::Object* MonitorExitVisitor(mirror::Object* object, void* arg)
+ NO_THREAD_SAFETY_ANALYSIS {
Thread* self = reinterpret_cast<Thread*>(arg);
- mirror::Object* entered_monitor = const_cast<mirror::Object*>(object);
+ mirror::Object* entered_monitor = object;
if (self->HoldsLock(entered_monitor)) {
LOG(WARNING) << "Calling MonitorExit on object "
<< object << " (" << PrettyTypeOf(object) << ")"
@@ -1022,6 +1023,7 @@
<< *Thread::Current() << " which is detaching";
entered_monitor->MonitorExit(self);
}
+ return object;
}
void Thread::Destroy() {
@@ -1151,8 +1153,12 @@
size_t num_refs = cur->NumberOfReferences();
for (size_t j = 0; j < num_refs; j++) {
mirror::Object* object = cur->GetReference(j);
- if (object != NULL) {
- visitor(object, arg);
+ if (object != nullptr) {
+ const mirror::Object* new_obj = visitor(object, arg);
+ DCHECK(new_obj != nullptr);
+ if (new_obj != object) {
+ cur->SetReference(j, const_cast<mirror::Object*>(new_obj));
+ }
}
}
}
@@ -2019,8 +2025,11 @@
// SIRT for JNI or References for interpreter.
for (size_t reg = 0; reg < num_regs; ++reg) {
mirror::Object* ref = shadow_frame->GetVRegReference(reg);
- if (ref != NULL) {
- visitor_(ref, reg, this);
+ if (ref != nullptr) {
+ mirror::Object* new_ref = visitor_(ref, reg, this);
+ if (new_ref != ref) {
+ shadow_frame->SetVRegReference(reg, new_ref);
+ }
}
}
} else {
@@ -2040,8 +2049,11 @@
for (size_t reg = 0; reg < num_regs; ++reg) {
if (TestBitmap(reg, reg_bitmap)) {
mirror::Object* ref = shadow_frame->GetVRegReference(reg);
- if (ref != NULL) {
- visitor_(ref, reg, this);
+ if (ref != nullptr) {
+ mirror::Object* new_ref = visitor_(ref, reg, this);
+ if (new_ref != ref) {
+ shadow_frame->SetVRegReference(reg, new_ref);
+ }
}
}
}
@@ -2072,19 +2084,25 @@
// Does this register hold a reference?
if (TestBitmap(reg, reg_bitmap)) {
uint32_t vmap_offset;
- mirror::Object* ref;
if (vmap_table.IsInContext(reg, kReferenceVReg, &vmap_offset)) {
- uintptr_t val = GetGPR(vmap_table.ComputeRegister(core_spills, vmap_offset,
- kReferenceVReg));
- ref = reinterpret_cast<mirror::Object*>(val);
+ int vmap_reg = vmap_table.ComputeRegister(core_spills, vmap_offset, kReferenceVReg);
+ mirror::Object* ref = reinterpret_cast<mirror::Object*>(GetGPR(vmap_reg));
+ if (ref != nullptr) {
+ mirror::Object* new_ref = visitor_(ref, reg, this);
+ if (ref != new_ref) {
+ SetGPR(vmap_reg, reinterpret_cast<uintptr_t>(new_ref));
+ }
+ }
} else {
- ref = reinterpret_cast<mirror::Object*>(GetVReg(cur_quick_frame, code_item,
- core_spills, fp_spills, frame_size,
- reg));
- }
-
- if (ref != NULL) {
- visitor_(ref, reg, this);
+ uint32_t* reg_addr =
+ GetVRegAddr(cur_quick_frame, code_item, core_spills, fp_spills, frame_size, reg);
+ mirror::Object* ref = reinterpret_cast<mirror::Object*>(*reg_addr);
+ if (ref != nullptr) {
+ mirror::Object* new_ref = visitor_(ref, reg, this);
+ if (ref != new_ref) {
+ *reg_addr = reinterpret_cast<uint32_t>(new_ref);
+ }
+ }
}
}
}
@@ -2110,8 +2128,8 @@
public:
RootCallbackVisitor(RootVisitor* visitor, void* arg) : visitor_(visitor), arg_(arg) {}
- void operator()(const mirror::Object* obj, size_t, const StackVisitor*) const {
- visitor_(obj, arg_);
+ mirror::Object* operator()(mirror::Object* obj, size_t, const StackVisitor*) const {
+ return visitor_(obj, arg_);
}
private:
@@ -2135,67 +2153,17 @@
void* const arg_;
};
-struct VerifyRootWrapperArg {
- VerifyRootVisitor* visitor;
- void* arg;
-};
-
-static void VerifyRootWrapperCallback(const mirror::Object* root, void* arg) {
- VerifyRootWrapperArg* wrapperArg = reinterpret_cast<VerifyRootWrapperArg*>(arg);
- wrapperArg->visitor(root, wrapperArg->arg, 0, NULL);
-}
-
-void Thread::VerifyRoots(VerifyRootVisitor* visitor, void* arg) {
- // We need to map from a RootVisitor to VerifyRootVisitor, so pass in nulls for arguments we
- // don't have.
- VerifyRootWrapperArg wrapperArg;
- wrapperArg.arg = arg;
- wrapperArg.visitor = visitor;
-
- if (opeer_ != NULL) {
- VerifyRootWrapperCallback(opeer_, &wrapperArg);
- }
- if (exception_ != NULL) {
- VerifyRootWrapperCallback(exception_, &wrapperArg);
- }
- throw_location_.VisitRoots(VerifyRootWrapperCallback, &wrapperArg);
- if (class_loader_override_ != NULL) {
- VerifyRootWrapperCallback(class_loader_override_, &wrapperArg);
- }
- jni_env_->locals.VisitRoots(VerifyRootWrapperCallback, &wrapperArg);
- jni_env_->monitors.VisitRoots(VerifyRootWrapperCallback, &wrapperArg);
-
- SirtVisitRoots(VerifyRootWrapperCallback, &wrapperArg);
-
- // Visit roots on this thread's stack
- Context* context = GetLongJumpContext();
- VerifyCallbackVisitor visitorToCallback(visitor, arg);
- ReferenceMapVisitor<VerifyCallbackVisitor> mapper(this, context, visitorToCallback);
- mapper.WalkStack();
- ReleaseLongJumpContext(context);
-
- std::deque<instrumentation::InstrumentationStackFrame>* instrumentation_stack = GetInstrumentationStack();
- typedef std::deque<instrumentation::InstrumentationStackFrame>::const_iterator It;
- for (It it = instrumentation_stack->begin(), end = instrumentation_stack->end(); it != end; ++it) {
- mirror::Object* this_object = (*it).this_object_;
- if (this_object != NULL) {
- VerifyRootWrapperCallback(this_object, &wrapperArg);
- }
- mirror::ArtMethod* method = (*it).method_;
- VerifyRootWrapperCallback(method, &wrapperArg);
- }
-}
-
void Thread::VisitRoots(RootVisitor* visitor, void* arg) {
- if (opeer_ != NULL) {
- visitor(opeer_, arg);
+ if (opeer_ != nullptr) {
+ opeer_ = visitor(opeer_, arg);
}
- if (exception_ != NULL) {
- visitor(exception_, arg);
+ if (exception_ != nullptr) {
+ exception_ = reinterpret_cast<mirror::Throwable*>(visitor(exception_, arg));
}
throw_location_.VisitRoots(visitor, arg);
- if (class_loader_override_ != NULL) {
- visitor(class_loader_override_, arg);
+ if (class_loader_override_ != nullptr) {
+ class_loader_override_ = reinterpret_cast<mirror::ClassLoader*>(
+ visitor(class_loader_override_, arg));
}
jni_env_->locals.VisitRoots(visitor, arg);
jni_env_->monitors.VisitRoots(visitor, arg);
@@ -2209,24 +2177,26 @@
mapper.WalkStack();
ReleaseLongJumpContext(context);
- for (const instrumentation::InstrumentationStackFrame& frame : *GetInstrumentationStack()) {
- mirror::Object* this_object = frame.this_object_;
- if (this_object != NULL) {
- visitor(this_object, arg);
+ for (instrumentation::InstrumentationStackFrame& frame : *GetInstrumentationStack()) {
+ if (frame.this_object_ != nullptr) {
+ frame.this_object_ = visitor(frame.this_object_, arg);
+ DCHECK(frame.this_object_ != nullptr);
}
- mirror::ArtMethod* method = frame.method_;
- visitor(method, arg);
+ frame.method_ = reinterpret_cast<mirror::ArtMethod*>(visitor(frame.method_, arg));
+ DCHECK(frame.method_ != nullptr);
}
}
-static void VerifyObject(const mirror::Object* root, void* arg) {
- gc::Heap* heap = reinterpret_cast<gc::Heap*>(arg);
- heap->VerifyObject(root);
+static mirror::Object* VerifyRoot(mirror::Object* root, void* arg) {
+ DCHECK(root != nullptr);
+ DCHECK(arg != nullptr);
+ reinterpret_cast<gc::Heap*>(arg)->VerifyObject(root);
+ return root;
}
void Thread::VerifyStackImpl() {
UniquePtr<Context> context(Context::Create());
- RootCallbackVisitor visitorToCallback(VerifyObject, Runtime::Current()->GetHeap());
+ RootCallbackVisitor visitorToCallback(VerifyRoot, Runtime::Current()->GetHeap());
ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context.get(), visitorToCallback);
mapper.WalkStack();
}