[oilpan] Rename visit to mark.

Source/heap/Heap.cpp

Index: Source/heap/Heap.cpp
diff --git a/Source/heap/Heap.cpp b/Source/heap/Heap.cpp
index 0910d5e38091d95133926bcf0433eb24b6fc4b00..0eaa9f29fdf90305fc653f406b25bf51abc6d949 100644
--- a/Source/heap/Heap.cpp
+++ b/Source/heap/Heap.cpp
@@ -471,29 +471,29 @@ bool LargeHeapObject<Header>::isMarked()
 }
 
 template<typename Header>
-bool LargeHeapObject<Header>::checkAndVisitPointer(Visitor* visitor, Address address)
+bool LargeHeapObject<Header>::checkAndMarkPointer(Visitor* visitor, Address address)
 {
     if (contains(address)) {
 #if defined(TRACE_GC_MARKING) && TRACE_GC_MARKING
         visitor->setHostInfo(&address, "stack");
 #endif
-        visit(visitor);
+        trace(visitor);
         return true;
     }
     return false;
 }
 
 template<>
-void LargeHeapObject<FinalizedHeapObjectHeader>::visit(Visitor* visitor)
+void LargeHeapObject<FinalizedHeapObjectHeader>::trace(Visitor* visitor)
 {
-    visitor->visit(heapObjectHeader(), heapObjectHeader()->traceCallback());
+    visitor->mark(heapObjectHeader(), heapObjectHeader()->traceCallback());
 }
 
 template<>
-void LargeHeapObject<HeapObjectHeader>::visit(Visitor* visitor)
+void LargeHeapObject<HeapObjectHeader>::trace(Visitor* visitor)
 {
     ASSERT(gcInfo());
-    visitor->visit(heapObjectHeader(), gcInfo()->m_trace);
+    visitor->mark(heapObjectHeader(), gcInfo()->m_trace);
 }
 
 template<>
@@ -605,13 +605,13 @@ bool Heap::contains(Address address)
     return false;
 }
 
-Address Heap::checkAndVisitPointer(Visitor* visitor, Address address)
+Address Heap::checkAndMarkPointer(Visitor* visitor, Address address)
 {
     ASSERT(ThreadState::isAnyThreadInGC());
     ThreadState::AttachedThreadStateSet& threads = ThreadState::attachedThreads();
     for (ThreadState::AttachedThreadStateSet::iterator it = threads.begin(), end = threads.end(); it != end; ++it) {
-        if ((*it)->checkAndVisitPointer(visitor, address)) {
-            // Pointer found and visited
+        if ((*it)->checkAndMarkPointer(visitor, address)) {
+            // Pointer found and marked.
             return address;
         }
     }
@@ -639,10 +639,10 @@ BaseHeapPage* ThreadHeap<Header>::largeHeapObjectFromAddress(Address address)
 }
 
 template<typename Header>
-bool ThreadHeap<Header>::checkAndVisitLargeHeapObjects(Visitor* visitor, Address address)
+bool ThreadHeap<Header>::checkAndMarkLargeHeapObjects(Visitor* visitor, Address address)
 {
     for (LargeHeapObject<Header>* current = m_firstLargeHeapObject; current; current = current->next()) {
-        if (current->checkAndVisitPointer(visitor, address))
+        if (current->checkAndMarkPointer(visitor, address))
             return true;
     }
     return false;
@@ -880,157 +880,6 @@ void Heap::getStats(HeapStats* stats)
     }
 }
 
-#ifndef NDEBUG
-// #define ENABLE_TRACE_CHECKER
-#endif
-
-#ifdef ENABLE_TRACE_CHECKER
-class TraceChecker {
-public:
-    TraceChecker(void* object, TraceCallback callback, TraceRequirement requirement)
-        : m_object(object)
-        , m_callback(callback)
-        , m_traceRequirement(requirement)
-        , m_previous(s_current)
-    {
-        s_current = this;
-        // Unmark the object pointed to by each intra-heap pointer we find by
-        // conservative scanning.
-        iteratePointers(clearMarksAction);
-    }
-
-    ~TraceChecker()
-    {
-        // Check the marks on the objects pointed to by each intra-heap pointer
-        // we find by conservative scanning.
-        if (m_traceRequirement == AllPointersMustBeVisited)
-            iteratePointers(checkDebugMarksAction);
-        else if (m_traceRequirement == AllPointersMustBeMarked)
-            iteratePointers(checkMarkedAction);
-        s_current = m_previous;
-    }
-
-    static void rememberedToVisit(HeapObjectHeader* header)
-    {
-        header->setDebugMark();
-    }
-
-    static void registerWeakPointers()
-    {
-        s_current->m_traceRequirement = NoRequirement;
-    }
-
-    static void init()
-    {
-        s_current = 0;
-    }
-
-private:
-    typedef void (*IntraHeapPointerAction)(TraceChecker* self, Address);
-
-    // Find the intra-heap pointers by scanning the allocated object
-    // conservatively.
-    void iteratePointers(IntraHeapPointerAction action)
-    {
-        HeapObjectHeader* header = HeapObjectHeader::fromPayload(m_object);
-        Address* start = reinterpret_cast<Address*>(m_object);
-        Address* limit = reinterpret_cast<Address*>(header->payloadEnd());
-
-        for (Address* p = start; p < limit; p++) {
-            Address address = *p;
-            Address* castAddress = reinterpret_cast<Address*>(address);
-            // Find out whether the pointer looks like a pointer to another
-            // object on the heap. We ignore pointers within the object itself.
-            // We assume that things that are not object aligned are not
-            // actually pointers.
-            if ((castAddress < start || castAddress >= limit)
-                && Heap::contains(address) && isObjectAligned(address))
-                action(this, address);
-        }
-    }
-
-    static void clearMarksAction(TraceChecker* self, Address address)
-    {
-        HeapObjectHeader* header = HeapObjectHeader::fromPayload(address);
-        // Unmark the object (if it was already marked) so that we can check
-        // the mark after the trace method to see if it has been marked again.
-        header->clearDebugMark();
-    }
-
-    static void checkDebugMarksAction(TraceChecker* self, Address address)
-    {
-        HeapObjectHeader* header = HeapObjectHeader::fromPayload(address);
-        if (!header->hasDebugMark()) {
-            self->reportMishandledPointer(
-                address,
-                "Failure to visit all intra-heap pointers in trace method");
-        }
-    }
-
-    static void checkMarkedAction(TraceChecker* self, Address address)
-    {
-        HeapObjectHeader* header = HeapObjectHeader::fromPayload(address);
-        if (!header->isMarked()) {
-            self->reportMishandledPointer(
-                address,
-                "Failure to visit all strong pointers or clear all weak pointers to dead objects");
-        }
-    }
-
-
-    void reportMishandledPointer(Address unvisitedAddress, const char* reason)
-    {
-        // Getting an assert in this method means either the trace method
-        // failed to visit a strong pointer, or the weak pointer callback failed
-        // to clear a weak pointer to an object that is dead.
-        class YouForgotToVisitAllPointersVisitor : public Visitor {
-        public:
-            virtual void visit(const void* objectPointer, TraceCallback callback)
-            {
-                ASSERT_NOT_REACHED(); // See comment below.
-            }
-        };
-
-        YouForgotToVisitAllPointersVisitor youForgotToVisitAllPointersVisitor;
-        // If the callback calls the visitor at least once it will assert, and
-        // we can catch the assert in the debugger with the offending callback
-        // on the stack, and the object that was insufficiently visited/cleared
-        // as its argument. In this frame, 'address' will tell you the pointer
-        // that was in the object, but which was not visited.
-        m_callback(&youForgotToVisitAllPointersVisitor, m_object);
-        // If we get here the callback did not even visit one pointer. Cause an
-        // assert here, and in the debugger you can get the address of the
-        // offending callback from the this->m_callback variable, and the
-        // unvisited/uncleared pointer from the 'address' argument. The object that
-        // contained the unvisited pointer is in this->m_object.
-        ASSERT_NOT_REACHED();
-    }
-
-    static bool isObjectAligned(Address address)
-    {
-        return !(reinterpret_cast<uintptr_t>(address) & allocationMask);
-    }
-
-    void* m_object;
-    TraceCallback m_callback;
-    TraceRequirement m_traceRequirement;
-    TraceChecker* m_previous;
-    static TraceChecker* s_current;
-};
-
-TraceChecker* TraceChecker::s_current;
-
-#else // !ENABLE_TRACE_CHECKER
-
-class TraceChecker {
-public:
-    TraceChecker(void*, TraceCallback, TraceRequirement) { }
-    static void rememberedToVisit(const HeapObjectHeader*) { }
-    static void init() { }
-    static void registerWeakPointers() { }
-};
-#endif // ENABLE_TRACE_CHECKER
-
 #if TRACE_GC_USING_CLASSOF
 static const char* classOf(const void* object)
 {
@@ -1058,7 +907,6 @@ public:
     {
         ASSERT(header);
         ASSERT(objectPointer);
-        TraceChecker::rememberedToVisit(header);
         if (header->isMarked())
             return;
         header->mark();
@@ -1071,21 +919,21 @@ public:
             Heap::pushTraceCallback(const_cast<void*>(objectPointer), callback);
     }
 
-    virtual void visit(HeapObjectHeader* header, TraceCallback callback)
+    virtual void mark(HeapObjectHeader* header, TraceCallback callback)
     {
         // We need both the HeapObjectHeader and FinalizedHeapObjectHeader version to
         // correctly find the payload.
         visitHeader(header, header->payload(), callback);
     }
 
-    virtual void visit(FinalizedHeapObjectHeader* header, TraceCallback callback)
+    virtual void mark(FinalizedHeapObjectHeader* header, TraceCallback callback)
     {
         // We need both the HeapObjectHeader and FinalizedHeapObjectHeader version to
         // correctly find the payload.
         visitHeader(header, header->payload(), callback);
     }
 
-    virtual void visit(const void* objectPointer, TraceCallback callback)
+    virtual void mark(const void* objectPointer, TraceCallback callback)
     {
         if (!objectPointer)
             return;
@@ -1095,7 +943,6 @@ public:
 
     virtual void registerWeakPointers(const void* containingObject, WeakPointerCallback callback)
     {
-        TraceChecker::registerWeakPointers();
         Heap::pushWeakCallback(const_cast<void*>(containingObject), callback);
     }
 
@@ -1106,7 +953,7 @@ public:
 
 // Macro to help defining the necessary visitor methods for typed heaps
 #define DEFINE_VISITOR_METHODS(Type)                                             \
-    virtual void visit(const Type* objectPointer, TraceCallback callback)       \
+    virtual void mark(const Type* objectPointer, TraceCallback callback)         \
     {                                                                            \
         if (!objectPointer)                                                      \
             return;                                                              \
@@ -1280,7 +1127,7 @@ static int numberOfLeadingZeroes(uint8_t byte)
 }
 
 template<typename Header>
-bool HeapPage<Header>::checkAndVisitPointer(Visitor* visitor, Address addr)
+bool HeapPage<Header>::checkAndMarkPointer(Visitor* visitor, Address addr)
 {
     if (addr < payload())
         return false;
@@ -1307,7 +1154,7 @@ bool HeapPage<Header>::checkAndVisitPointer(Visitor* visitor, Address addr)
 #if defined(TRACE_GC_MARKING) && TRACE_GC_MARKING
     visitor->setHostInfo(&addr, "stack");
 #endif
-    visitor->visit(header, traceCallback(header));
+    visitor->mark(header, traceCallback(header));
     return true;
 }
 
@@ -1407,7 +1254,7 @@ static void markingTrampoline(VisitorCallback callback, Visitor* visitor, void*
 
 bool Heap::popAndTraceMarkingStack(Visitor* visitor)
 {
-    return s_markingStack->popAndTrace(&s_markingStack, visitor, AllPointersMustBeVisited, markingTrampoline);
+    return s_markingStack->popAndTrace(&s_markingStack, visitor, markingTrampoline);
 }
 
 static void weakTrampoline(VisitorCallback callback, Visitor* visitor, void* p)
@@ -1417,7 +1264,7 @@ static void weakTrampoline(VisitorCallback callback, Visitor* visitor, void* p)
 
 bool Heap::popAndCallbackWeakPointer(Visitor* visitor)
 {
-    return s_weakCallbackStack->popAndTrace(&s_weakCallbackStack, visitor, AllPointersMustBeMarked, weakTrampoline);
+    return s_weakCallbackStack->popAndTrace(&s_weakCallbackStack, visitor, weakTrampoline);
 }
 
 class GCScope {
@@ -1539,7 +1386,7 @@ void Heap::collectGarbage(ThreadState::StackState stackState, CollectionType col
         // objects.
         while (popAndCallbackWeakPointer(&marker)) { }
     }
-    // It is not permitted to visit pointers of live objects in the weak
+    // It is not permitted to trace pointers of live objects in the weak
     // callback phase, so the marking stack should still be empty here.
     s_markingStack->assertIsEmpty();
 }
@@ -1560,7 +1407,6 @@ void Heap::pushWeakCallback(void* object, WeakPointerCallback callback)
 bool CallbackStack::popAndTrace(
     CallbackStack** first,
     Visitor* visitor,
-    TraceRequirement requirement,
     TraceTrampoline trampoline)
 {
     if (m_current == &(m_buffer[0])) {
@@ -1573,10 +1419,9 @@ bool CallbackStack::popAndTrace(
         CallbackStack* nextStack = m_next;
         *first = nextStack;
         delete this;
-        return nextStack->popAndTrace(first, visitor, requirement, trampoline);
+        return nextStack->popAndTrace(first, visitor, trampoline);
     }
     Item* item = --m_current;
-    TraceChecker checker(item->object(), item->callback(), requirement);
     trampoline(item->callback(), visitor, item->object());
 
     return true;