- Add a size field to the header.

vm/object.cc

Index: vm/object.cc
===================================================================
--- vm/object.cc	(revision 2918)
+++ vm/object.cc	(working copy)
@@ -703,6 +703,8 @@
 
 
 void Object::InitializeObject(uword address, intptr_t size) {
+  // TODO(iposva): Get a proper halt instruction from the assembler which
+  // would be needed here for code objects.
   uword initial_value = reinterpret_cast<uword>(null_);
   uword cur = address;
   uword end = address + size;
@@ -716,16 +718,18 @@
 RawObject* Object::Allocate(const Class& cls,
                             intptr_t size,
                             Heap::Space space) {
+  ASSERT(Utils::IsAligned(size, kObjectAlignment));
   Isolate* isolate = Isolate::Current();
   Heap* heap = isolate->heap();
 
-  // TODO(iposva): Get a proper halt instruction from the assembler.
   uword address = heap->Allocate(size, space);
   NoGCScope no_gc;
   InitializeObject(address, size);
   RawObject* raw_obj = reinterpret_cast<RawObject*>(address + kHeapObjectTag);
   raw_obj->ptr()->class_ = cls.raw();
-  raw_obj->ptr()->tags_ = 0;
+  uword tags = 0;
+  tags = RawObject::SizeTag::update(size, tags);
+  raw_obj->ptr()->tags_ = tags;
   return raw_obj;
 }