[Compiler] Enable use of seperate zones for parsing and compiling.

src/zone/zone.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_ZONE_ZONE_H_
 #define V8_ZONE_ZONE_H_
 
 #include <limits>
 
 #include "src/base/hashmap.h"
@@ skipping 32 matching lines @@
   // Allocate 'size' bytes of memory in the Zone; expands the Zone by
   // allocating new segments of memory on demand using malloc().
   void* New(size_t size);
 
   template <typename T>
   T* NewArray(size_t length) {
     DCHECK_LT(length, std::numeric_limits<size_t>::max() / sizeof(T));
     return static_cast<T*>(New(length * sizeof(T)));
   }
 
+  // Seals the zone to prevent any further allocation.
+  void Seal() { sealed_ = true; }
+
   // Returns true if more memory has been allocated in zones than
   // the limit allows.
   bool excess_allocation() const {
     return segment_bytes_allocated_ > kExcessLimit;
   }
 
   const char* name() const { return name_; }
 
   size_t allocation_size() const { return allocation_size_; }
 
@@ skipping 36 matching lines @@
   // The free region in the current (front) segment is represented as
   // the half-open interval [position, limit). The 'position' variable
   // is guaranteed to be aligned as dictated by kAlignment.
   Address position_;
   Address limit_;
 
   AccountingAllocator* allocator_;
 
   Segment* segment_head_;
   const char* name_;
+  bool sealed_;
 };
 
 // ZoneObject is an abstraction that helps define classes of objects
 // allocated in the Zone. Use it as a base class; see ast.h.
 class ZoneObject {
  public:
   // Allocate a new ZoneObject of 'size' bytes in the Zone.
   void* operator new(size_t size, Zone* zone) { return zone->New(size); }
 
   // Ideally, the delete operator should be private instead of
@@ skipping 103 matching lines @@
 
 typedef base::PointerTemplateHashMapImpl<ZoneAllocationPolicy> ZoneHashMap;
 
 typedef base::CustomMatcherTemplateHashMapImpl<ZoneAllocationPolicy>
     CustomMatcherZoneHashMap;
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ZONE_ZONE_H_