Remove saving/restoring of the context at function entry.

runtime/vm/parser.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_PARSER_H_
 #define VM_PARSER_H_
 
 #include "include/dart_api.h"
 
 #include "platform/assert.h"
@@ skipping 27 matching lines @@
 // The class ParsedFunction holds the result of parsing a function.
 class ParsedFunction : public ZoneAllocated {
  public:
   ParsedFunction(Isolate* isolate, const Function& function)
       : function_(function),
         code_(Code::Handle(isolate, function.unoptimized_code())),
         node_sequence_(NULL),
         instantiator_(NULL),
         default_parameter_values_(Array::ZoneHandle(isolate, Array::null())),
         current_context_var_(NULL),
-        saved_entry_context_var_(NULL),
         expression_temp_var_(NULL),
         finally_return_temp_var_(NULL),
         deferred_prefixes_(new ZoneGrowableArray<const LibraryPrefix*>()),
         first_parameter_index_(0),
         first_stack_local_index_(0),
         num_copied_params_(0),
         num_stack_locals_(0),
         have_seen_await_expr_(false),
         saved_try_ctx_(NULL),
         async_saved_try_ctx_name_(String::ZoneHandle(isolate, String::null())),
@@ skipping 26 matching lines @@
   void set_default_parameter_values(const Array& default_parameter_values) {
     ASSERT(default_parameter_values.IsZoneHandle() ||
            default_parameter_values.InVMHeap());
     default_parameter_values_ = default_parameter_values.raw();
   }
 
   LocalVariable* current_context_var() const {
     return current_context_var_;
   }
 
-  LocalVariable* saved_entry_context_var() const {
-    return saved_entry_context_var_;
-  }
-  void set_saved_entry_context_var(LocalVariable* saved_entry_context_var) {
-    ASSERT(saved_entry_context_var != NULL);
-    saved_entry_context_var_ = saved_entry_context_var;
-  }
-
   LocalVariable* expression_temp_var() const {
     ASSERT(has_expression_temp_var());
     return expression_temp_var_;
   }
   void set_expression_temp_var(LocalVariable* value) {
     ASSERT(!has_expression_temp_var());
     expression_temp_var_ = value;
   }
   bool has_expression_temp_var() const {
     return expression_temp_var_ != NULL;
@@ skipping 53 matching lines @@
 
   Isolate* isolate() const { return isolate_; }
 
  private:
   const Function& function_;
   Code& code_;
   SequenceNode* node_sequence_;
   LocalVariable* instantiator_;
   Array& default_parameter_values_;
   LocalVariable* current_context_var_;
-  LocalVariable* saved_entry_context_var_;
   LocalVariable* expression_temp_var_;
   LocalVariable* finally_return_temp_var_;
   ZoneGrowableArray<const LibraryPrefix*>* deferred_prefixes_;
 
   int first_parameter_index_;
   int first_stack_local_index_;
   int num_copied_params_;
   int num_stack_locals_;
   bool have_seen_await_expr_;
   LocalVariable* saved_try_ctx_;
@@ skipping 625 matching lines @@
   bool unregister_pending_function_;
 
   LocalScope* async_temp_scope_;
 
   DISALLOW_COPY_AND_ASSIGN(Parser);
 };
 
 }  // namespace dart
 
 #endif  // VM_PARSER_H_