Revert of Revert of Simplify and compact transitions storage

test/cctest/test-heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2124 matching lines @@
     v8::Handle<v8::Function> g =
         v8::Handle<v8::Function>::Cast(global->Get(v8_str("g")));
     g->Call(global, 0, NULL);
   }
 
   CcTest::heap()->incremental_marking()->set_should_hurry(true);
   CcTest::heap()->CollectGarbage(OLD_POINTER_SPACE);
 }
 
 
+static int NumberOfProtoTransitions(Map* map) {
+  return TransitionArray::NumberOfPrototypeTransitions(
+      TransitionArray::GetPrototypeTransitions(map));
+}
+
+
 TEST(PrototypeTransitionClearing) {
   if (FLAG_never_compact) return;
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
   Factory* factory = isolate->factory();
   v8::HandleScope scope(CcTest::isolate());
 
   CompileRun("var base = {};");
   Handle<JSObject> baseObject =
       v8::Utils::OpenHandle(
           *v8::Handle<v8::Object>::Cast(
               CcTest::global()->Get(v8_str("base"))));
-  int initialTransitions = baseObject->map()->NumberOfProtoTransitions();
+  int initialTransitions = NumberOfProtoTransitions(baseObject->map());
 
   CompileRun(
       "var live = [];"
       "for (var i = 0; i < 10; i++) {"
       "  var object = {};"
       "  var prototype = {};"
       "  object.__proto__ = prototype;"
       "  if (i >= 3) live.push(object, prototype);"
       "}");
 
   // Verify that only dead prototype transitions are cleared.
   CHECK_EQ(initialTransitions + 10,
-      baseObject->map()->NumberOfProtoTransitions());
+           NumberOfProtoTransitions(baseObject->map()));
   CcTest::heap()->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
   const int transitions = 10 - 3;
   CHECK_EQ(initialTransitions + transitions,
-      baseObject->map()->NumberOfProtoTransitions());
+           NumberOfProtoTransitions(baseObject->map()));
 
   // Verify that prototype transitions array was compacted.
-  FixedArray* trans = baseObject->map()->GetPrototypeTransitions();
+  FixedArray* trans =
+      TransitionArray::GetPrototypeTransitions(baseObject->map());
   for (int i = initialTransitions; i < initialTransitions + transitions; i++) {
-    int j = Map::kProtoTransitionHeaderSize + i;
+    int j = TransitionArray::kProtoTransitionHeaderSize + i;
     CHECK(trans->get(j)->IsMap());
   }
 
   // Make sure next prototype is placed on an old-space evacuation candidate.
   Handle<JSObject> prototype;
   PagedSpace* space = CcTest::heap()->old_pointer_space();
   {
     AlwaysAllocateScope always_allocate(isolate);
     SimulateFullSpace(space);
     prototype = factory->NewJSArray(32 * KB, FAST_HOLEY_ELEMENTS, TENURED);
   }
 
   // Add a prototype on an evacuation candidate and verify that transition
   // clearing correctly records slots in prototype transition array.
   i::FLAG_always_compact = true;
   Handle<Map> map(baseObject->map());
   CHECK(!space->LastPage()->Contains(
-      map->GetPrototypeTransitions()->address()));
+      TransitionArray::GetPrototypeTransitions(*map)->address()));
   CHECK(space->LastPage()->Contains(prototype->address()));
 }
 
 
 TEST(ResetSharedFunctionInfoCountersDuringIncrementalMarking) {
   i::FLAG_stress_compaction = false;
   i::FLAG_allow_natives_syntax = true;
 #ifdef VERIFY_HEAP
   i::FLAG_verify_heap = true;
 #endif
@@ skipping 662 matching lines @@
            v8::Object::Cast(*res)->Get(v8_str("0"))->Int32Value());
 
   Handle<JSObject> o =
       v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
 
   CHECK(CcTest::heap()->InNewSpace(o->elements()));
 }
 
 
 static int CountMapTransitions(Map* map) {
-  return map->transitions()->number_of_transitions();
+  return TransitionArray::NumberOfTransitions(map->raw_transitions());
 }
 
 
 // Test that map transitions are cleared and maps are collected with
 // incremental marking as well.
 TEST(Regress1465) {
   i::FLAG_stress_compaction = false;
   i::FLAG_allow_natives_syntax = true;
   i::FLAG_trace_incremental_marking = true;
   i::FLAG_retain_maps_for_n_gc = 0;
@@ skipping 160 matching lines @@
   CompileRun("var root = new F;");
   Handle<JSObject> root = GetByName("root");
 
   // Count number of live transitions before marking.
   int transitions_before = CountMapTransitions(root->map());
   CHECK_EQ(transitions_count, transitions_before);
 
   CompileRun("o = new F;"
              "root = new F");
   root = GetByName("root");
-  DCHECK(root->map()->transitions()->IsSimpleTransition());
+  DCHECK(TransitionArray::IsSimpleTransition(root->map()->raw_transitions()));
   AddPropertyTo(2, root, "happy");
 
   // Count number of live transitions after marking.  Note that one transition
   // is left, because 'o' still holds an instance of one transition target.
   int transitions_after = CountMapTransitions(
       Map::cast(root->map()->GetBackPointer()));
   CHECK_EQ(1, transitions_after);
 }
 #endif  // DEBUG
 
@@ skipping 2059 matching lines @@
 
 TEST(WritableVsImmortalRoots) {
   for (int i = 0; i < Heap::kStrongRootListLength; ++i) {
     Heap::RootListIndex root_index = static_cast<Heap::RootListIndex>(i);
     bool writable = Heap::RootCanBeWrittenAfterInitialization(root_index);
     bool immortal = Heap::RootIsImmortalImmovable(root_index);
     // A root value can be writable, immortal, or neither, but not both.
     CHECK(!immortal || !writable);
   }
 }