Implement unaligned allocate and allocate heap numbers in runtime double unaligned.

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 701 matching lines @@
 
   // Returns a deep copy of the JavaScript object.
   // Properties and elements are copied too.
   // Optionally takes an AllocationSite to be appended in an AllocationMemento.
   MUST_USE_RESULT AllocationResult
       CopyJSObject(JSObject* source, AllocationSite* site = NULL);
 
   // This method assumes overallocation of one word. It will store a filler
   // before the object if the given object is not double aligned, otherwise
   // it will place the filler after the object.
-  MUST_USE_RESULT HeapObject* EnsureDoubleAligned(HeapObject* object, int size);
+  MUST_USE_RESULT HeapObject* EnsureAligned(HeapObject* object, int size,
+                                            AllocationAlignment alignment);
+
+  MUST_USE_RESULT HeapObject* PrecedeWithFiller(HeapObject* object);
 
   // Clear the Instanceof cache (used when a prototype changes).
   inline void ClearInstanceofCache();
 
   // Iterates the whole code space to clear all ICs of the given kind.
   void ClearAllICsByKind(Code::Kind kind);
 
   // FreeSpace objects have a null map after deserialization. Update the map.
   void RepairFreeListsAfterDeserialization();
 
@@ skipping 1079 matching lines @@
   // Selects the proper allocation space depending on the given object
   // size and pretenuring decision.
   static AllocationSpace SelectSpace(int object_size,
                                      PretenureFlag pretenure) {
     if (object_size > Page::kMaxRegularHeapObjectSize) return LO_SPACE;
     return (pretenure == TENURED) ? OLD_SPACE : NEW_SPACE;
   }
 
   HeapObject* DoubleAlignForDeserialization(HeapObject* object, int size);
 
-  enum Alignment { kWordAligned, kDoubleAligned };
-
   // Allocate an uninitialized object.  The memory is non-executable if the
   // hardware and OS allow.  This is the single choke-point for allocations
   // performed by the runtime and should not be bypassed (to extend this to
   // inlined allocations, use the Heap::DisableInlineAllocation() support).
   MUST_USE_RESULT inline AllocationResult AllocateRaw(
       int size_in_bytes, AllocationSpace space, AllocationSpace retry_space,
-      Alignment aligment = kWordAligned);
+      AllocationAlignment aligment = kWordAligned);
 
   // Allocates a heap object based on the map.
   MUST_USE_RESULT AllocationResult
       Allocate(Map* map, AllocationSpace space,
                AllocationSite* allocation_site = NULL);
 
   // Allocates a partial map for bootstrapping.
   MUST_USE_RESULT AllocationResult
       AllocatePartialMap(InstanceType instance_type, int instance_size);
 
@@ skipping 807 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_HEAP_H_