Split incremental marking write barrier into fast and slow paths.

src/incremental-marking.h

Index: src/incremental-marking.h
diff --git a/src/incremental-marking.h b/src/incremental-marking.h
index fa7337b78fd5ae822ae787b8f09d00478d530f5e..4542fbd00a3d1d4b8f0a64938064ebe032a48c3d 100644
--- a/src/incremental-marking.h
+++ b/src/incremental-marking.h
@@ -59,7 +59,7 @@ class IncrementalMarking {
 
   inline bool IsStopped() { return state() == STOPPED; }
 
-  inline bool IsMarking() { return state() >= MARKING; }
+  INLINE(bool IsMarking()) { return state() >= MARKING; }
 
   inline bool IsMarkingIncomplete() { return state() == MARKING; }
 
@@ -120,16 +120,23 @@ class IncrementalMarking {
                                                Object** slot,
                                                Isolate* isolate);
 
-  inline bool BaseRecordWrite(HeapObject* obj, Object** slot, Object* value);
+  INLINE(bool BaseRecordWrite(HeapObject* obj, Object** slot, Object* value));
+  INLINE(void RecordWrite(HeapObject* obj, Object** slot, Object* value));
+  INLINE(void RecordWriteIntoCode(HeapObject* obj,
+                                  RelocInfo* rinfo,
+                                  Object* value));
+  INLINE(void RecordWriteOfCodeEntry(JSFunction* host,
+                                     Object** slot,
+                                     Code* value));
 
 
-  inline void RecordWrite(HeapObject* obj, Object** slot, Object* value);
-  inline void RecordWriteIntoCode(HeapObject* obj,
-                                  RelocInfo* rinfo,
-                                  Object* value);
+  void RecordWriteSlow(HeapObject* obj, Object** slot, Object* value);
+  void RecordWriteIntoCodeSlow(HeapObject* obj,
+                               RelocInfo* rinfo,
+                               Object* value);
+  void RecordWriteOfCodeEntrySlow(JSFunction* host, Object** slot, Code* value);
   void RecordCodeTargetPatch(Code* host, Address pc, HeapObject* value);
   void RecordCodeTargetPatch(Address pc, HeapObject* value);
-  void RecordWriteOfCodeEntry(JSFunction* host, Object** slot, Code* value);
 
   inline void RecordWrites(HeapObject* obj);