Made zone segments aligned in memory and included a pointer to the zone in the header. Larger objec…

src/base/platform/platform.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.
 
 // This module contains the platform-specific code. This make the rest of the
 // code less dependent on operating system, compilers and runtime libraries.
 // This module does specifically not deal with differences between different
 // processor architecture.
 // The platform classes have the same definition for all platforms. The
 // implementation for a particular platform is put in platform_<os>.cc.
@@ skipping 277 matching lines @@
 // from the original object.
 class VirtualMemory {
  public:
   // Empty VirtualMemory object, controlling no reserved memory.
   VirtualMemory();
 
   // Reserves virtual memory with size.
   explicit VirtualMemory(size_t size);
 
   // Reserves virtual memory containing an area of the given size that
-  // is aligned per alignment. This may not be at the position returned
-  // by address().
+  // is aligned per alignment.
   VirtualMemory(size_t size, size_t alignment);
 
   // Construct a virtual memory by assigning it some already mapped address
   // and size.
   VirtualMemory(void* address, size_t size) : address_(address), size_(size) {}
 
   // Releases the reserved memory, if any, controlled by this VirtualMemory
   // object.
   ~VirtualMemory();
 
   // Returns whether the memory has been reserved.
-  bool IsReserved();
+  bool IsReserved() const;
 
   // Initialize or resets an embedded VirtualMemory object.
   void Reset();
 
   // Returns the start address of the reserved memory.
-  // If the memory was reserved with an alignment, this address is not
-  // necessarily aligned. The user might need to round it up to a multiple of
-  // the alignment to get the start of the aligned block.
-  void* address() {
+  void* address() const {
     DCHECK(IsReserved());
     return address_;
   }
 
   // Returns the size of the reserved memory. The returned value is only
   // meaningful when IsReserved() returns true.
-  // If the memory was reserved with an alignment, this size may be larger
-  // than the requested size.
-  size_t size() { return size_; }
+  size_t size() const { return size_; }
 
   // Commits real memory. Returns whether the operation succeeded.
   bool Commit(void* address, size_t size, bool is_executable);
 
   // Uncommit real memory.  Returns whether the operation succeeded.
   bool Uncommit(void* address, size_t size);
 
   // Creates a single guard page at the given address.
   bool Guard(void* address);
 
@@ skipping 172 matching lines @@
   int stack_size_;
   Semaphore* start_semaphore_;
 
   DISALLOW_COPY_AND_ASSIGN(Thread);
 };
 
 }  // namespace base
 }  // namespace v8
 
 #endif  // V8_BASE_PLATFORM_PLATFORM_H_