Double the default heap size on 64-bit platforms to account for all pointers taking up twice the am…

runtime/vm/heap.h

 // Copyright (c) 2012, 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_HEAP_H_
 #define VM_HEAP_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/flags.h"
@@ skipping 37 matching lines @@
   enum GCReason {
     kNewSpace,
     kPromotionFailure,
     kOldSpace,
     kFull,
     kGCAtAlloc,
     kGCTestCase,
   };
 
   // Default allocation sizes in MB for the old gen and code heaps.
-  static const intptr_t kHeapSizeInMB = 512;
+  static const intptr_t kHeapSizeInMWords = 128;
+  static const intptr_t kHeapSizeInMB = kHeapSizeInMWords * kWordSize;
   static const intptr_t kCodeHeapSizeInMB = 18;
 
   ~Heap();
 
   uword Allocate(intptr_t size, Space space) {
     ASSERT(!read_only_);
     switch (space) {
       case kNew:
         // Do not attempt to allocate very large objects in new space.
         if (!IsAllocatableInNewSpace(size)) {
@@ skipping 252 matching lines @@
   NoHeapGrowthControlScope();
   ~NoHeapGrowthControlScope();
  private:
   bool current_growth_controller_state_;
   DISALLOW_COPY_AND_ASSIGN(NoHeapGrowthControlScope);
 };
 
 }  // namespace dart
 
 #endif  // VM_HEAP_H_