Introduce global contexts to represent lexical global scope(s).

src/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 112 matching lines @@
   V(Map, external_int_array_map, ExternalIntArrayMap)                          \
   V(Map, external_unsigned_int_array_map, ExternalUnsignedIntArrayMap)         \
   V(Map, external_float_array_map, ExternalFloatArrayMap)                      \
   V(Map, external_double_array_map, ExternalDoubleArrayMap)                    \
   V(Map, non_strict_arguments_elements_map, NonStrictArgumentsElementsMap)     \
   V(Map, function_context_map, FunctionContextMap)                             \
   V(Map, catch_context_map, CatchContextMap)                                   \
   V(Map, with_context_map, WithContextMap)                                     \
   V(Map, block_context_map, BlockContextMap)                                   \
   V(Map, module_context_map, ModuleContextMap)                                 \
+  V(Map, global_context_map, GlobalContextMap)                                 \
   V(Map, oddball_map, OddballMap)                                              \
   V(Map, message_object_map, JSMessageObjectMap)                               \
   V(Map, foreign_map, ForeignMap)                                              \
   V(HeapNumber, nan_value, NanValue)                                           \
   V(HeapNumber, infinity_value, InfinityValue)                                 \
   V(HeapNumber, minus_zero_value, MinusZeroValue)                              \
   V(Map, neander_map, NeanderMap)                                              \
   V(JSObject, message_listeners, MessageListeners)                             \
   V(Foreign, prototype_accessors, PrototypeAccessors)                          \
   V(UnseededNumberDictionary, code_stubs, CodeStubs)                           \
@@ skipping 676 matching lines @@
       PretenureFlag pretenure = NOT_TENURED);
 
   // AllocateHashTable is identical to AllocateFixedArray except
   // that the resulting object has hash_table_map as map.
   MUST_USE_RESULT MaybeObject* AllocateHashTable(
       int length, PretenureFlag pretenure = NOT_TENURED);
 
   // Allocate a native (but otherwise uninitialized) context.
   MUST_USE_RESULT MaybeObject* AllocateNativeContext();
 
+  // Allocate a global context.
+  MUST_USE_RESULT MaybeObject* AllocateGlobalContext(JSFunction* function,
+                                                     ScopeInfo* scope_info);
+
   // Allocate a module context.
   MUST_USE_RESULT MaybeObject* AllocateModuleContext(ScopeInfo* scope_info);
 
   // Allocate a function context.
   MUST_USE_RESULT MaybeObject* AllocateFunctionContext(int length,
                                                        JSFunction* function);
 
   // Allocate a catch context.
   MUST_USE_RESULT MaybeObject* AllocateCatchContext(JSFunction* function,
                                                     Context* previous,
@@ skipping 1947 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_