Factor out handling of mixed objects preprocessing after migration

src/heap/mark-compact.cc

Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index 0da364b621cb997370bbe9298d929146e59006f2..83d819b5d77af4b093882c17f9c1f40c226cf592 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -2793,6 +2793,46 @@ void MarkCompactCollector::RecordMigratedSlot(Object* value, Address slot) {
 }
 
 
+void MarkCompactCollector::MigrateMixedObjectEpilog(HeapObject* dst) {
+  DCHECK(dst->MayContainMixedValues());
+  Address dst_addr = dst->address();
+  if (compacting_ && dst->IsJSFunction()) {
+    Address code_entry_slot = dst_addr + JSFunction::kCodeEntryOffset;
+    Address code_entry = Memory::Address_at(code_entry_slot);
+
+    if (Page::FromAddress(code_entry)->IsEvacuationCandidate()) {
+      SlotsBuffer::AddTo(&slots_buffer_allocator_, &migration_slots_buffer_,
+                         SlotsBuffer::CODE_ENTRY_SLOT, code_entry_slot,
+                         SlotsBuffer::IGNORE_OVERFLOW);
+    }
+  } else if (dst->IsConstantPoolArray()) {
+    // We special case ConstantPoolArrays since they could contain integers
+    // value entries which look like tagged pointers.
+    // TODO(mstarzinger): restructure this code to avoid this special-casing.
+    ConstantPoolArray* array = ConstantPoolArray::cast(dst);
+    ConstantPoolArray::Iterator code_iter(array, ConstantPoolArray::CODE_PTR);
+    while (!code_iter.is_finished()) {
+      Address code_entry_slot =
+          dst_addr + array->OffsetOfElementAt(code_iter.next_index());
+      Address code_entry = Memory::Address_at(code_entry_slot);
+
+      if (Page::FromAddress(code_entry)->IsEvacuationCandidate()) {
+        SlotsBuffer::AddTo(&slots_buffer_allocator_, &migration_slots_buffer_,
+                           SlotsBuffer::CODE_ENTRY_SLOT, code_entry_slot,
+                           SlotsBuffer::IGNORE_OVERFLOW);
+      }
+    }
+    ConstantPoolArray::Iterator heap_iter(array, ConstantPoolArray::HEAP_PTR);
+    while (!heap_iter.is_finished()) {
+      Address heap_slot =
+          dst_addr + array->OffsetOfElementAt(heap_iter.next_index());
+      Object* value = Memory::Object_at(heap_slot);
+      RecordMigratedSlot(value, heap_slot);
+    }
+  }
+}
+
+
 // We scavenge new space simultaneously with sweeping. This is done in two
 // passes.
 //
@@ -2842,41 +2882,7 @@ void MarkCompactCollector::MigrateObject(HeapObject* dst, HeapObject* src,
       src_slot += kPointerSize;
       dst_slot += kPointerSize;
     }
-
-    if (compacting_ && dst->IsJSFunction()) {
-      Address code_entry_slot = dst_addr + JSFunction::kCodeEntryOffset;
-      Address code_entry = Memory::Address_at(code_entry_slot);
-
-      if (Page::FromAddress(code_entry)->IsEvacuationCandidate()) {
-        SlotsBuffer::AddTo(&slots_buffer_allocator_, &migration_slots_buffer_,
-                           SlotsBuffer::CODE_ENTRY_SLOT, code_entry_slot,
-                           SlotsBuffer::IGNORE_OVERFLOW);
-      }
-    } else if (dst->IsConstantPoolArray()) {
-      // We special case ConstantPoolArrays since they could contain integers
-      // value entries which look like tagged pointers.
-      // TODO(mstarzinger): restructure this code to avoid this special-casing.
-      ConstantPoolArray* array = ConstantPoolArray::cast(dst);
-      ConstantPoolArray::Iterator code_iter(array, ConstantPoolArray::CODE_PTR);
-      while (!code_iter.is_finished()) {
-        Address code_entry_slot =
-            dst_addr + array->OffsetOfElementAt(code_iter.next_index());
-        Address code_entry = Memory::Address_at(code_entry_slot);
-
-        if (Page::FromAddress(code_entry)->IsEvacuationCandidate()) {
-          SlotsBuffer::AddTo(&slots_buffer_allocator_, &migration_slots_buffer_,
-                             SlotsBuffer::CODE_ENTRY_SLOT, code_entry_slot,
-                             SlotsBuffer::IGNORE_OVERFLOW);
-        }
-      }
-      ConstantPoolArray::Iterator heap_iter(array, ConstantPoolArray::HEAP_PTR);
-      while (!heap_iter.is_finished()) {
-        Address heap_slot =
-            dst_addr + array->OffsetOfElementAt(heap_iter.next_index());
-        Object* value = Memory::Object_at(heap_slot);
-        RecordMigratedSlot(value, heap_slot);
-      }
-    }
+    if (dst->MayContainMixedValues()) MigrateMixedObjectEpilog(dst);

[Igor Sheludko, 2015/05/13 12:22:59]

Do we need MayContainMixedValues() at all given that we are going to do
different stuff based on instance type anyway.

   } else if (dest == CODE_SPACE) {
     PROFILE(isolate(), CodeMoveEvent(src_addr, dst_addr));
     heap()->MoveBlock(dst_addr, src_addr, size);
@@ -2887,6 +2893,9 @@ void MarkCompactCollector::MigrateObject(HeapObject* dst, HeapObject* src,
   } else {
     DCHECK(dest == NEW_SPACE);
     heap()->MoveBlock(dst_addr, src_addr, size);
+    if (dst->MayContainMixedValues()) {
+      heap()->MigrateMixedObjectInNewSpaceEpilog(dst);
+    }
   }
   heap()->OnMoveEvent(dst, src, size);
   Memory::Address_at(src_addr) = dst_addr;