Last snapshot bits to get working precompiled hello_world on x64.

runtime/vm/pages.h

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_PAGES_H_
 #define VM_PAGES_H_
 
 #include "vm/freelist.h"
 #include "vm/globals.h"
 #include "vm/lockers.h"
@@ skipping 24 matching lines @@
   };
 
   HeapPage* next() const { return next_; }
   void set_next(HeapPage* next) { next_ = next; }
 
   bool Contains(uword addr) {
     return memory_->Contains(addr);
   }
 
   uword object_start() const {
-    return (reinterpret_cast<uword>(this) + ObjectStartOffset());
+    return memory_->start() + ObjectStartOffset();
   }
   uword object_end() const {
     return object_end_;
   }
 
   PageType type() const {
     return executable_ ? kExecutable : kData;
   }
 
   void VisitObjects(ObjectVisitor* visitor) const;
@@ skipping 277 matching lines @@
   // and illegal in debug mode.
   uword TryAllocateSmiInitializedLocked(intptr_t size,
                                         GrowthPolicy growth_policy);
 
   // Bump block allocation from generated code.
   uword* TopAddress() { return &bump_top_; }
   uword* EndAddress() { return &bump_end_; }
   static intptr_t top_offset() { return OFFSET_OF(PageSpace, bump_top_); }
   static intptr_t end_offset() { return OFFSET_OF(PageSpace, bump_end_); }
 
+  void SetupInstructionsSnapshotPage(void* pointer, uword size);
+
  private:
   // Ids for time and data records in Heap::GCStats.
   enum {
     // Time
     kMarkObjects = 0,
     kResetFreeLists = 1,
     kSweepPages = 2,
     kSweepLargePages = 3,
     // Data
     kGarbageRatio = 0,
@@ skipping 87 matching lines @@
   friend class HeapIterationScope;
   friend class PageSpaceController;
   friend class SweeperTask;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(PageSpace);
 };
 
 }  // namespace dart
 
 #endif  // VM_PAGES_H_