Improve async code in VM by not unnecessarily capturing parameters of async and

runtime/vm/flow_graph_builder.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_FLOW_GRAPH_BUILDER_H_
 #define VM_FLOW_GRAPH_BUILDER_H_
 
 #include "platform/assert.h"
 #include "platform/globals.h"
 #include "vm/allocation.h"
@@ skipping 146 matching lines @@
   // Manage the currently active try index.
   void set_try_index(intptr_t value) { try_index_ = value; }
   intptr_t try_index() const { return try_index_; }
 
   // Manage the currently active catch-handler try index.
   void set_catch_try_index(intptr_t value) { catch_try_index_ = value; }
   intptr_t catch_try_index() const { return catch_try_index_; }
 
   intptr_t next_await_counter() { return jump_count_++; }
 
-  ZoneGrowableArray<intptr_t>* await_levels() const { return await_levels_; }
   ZoneGrowableArray<JoinEntryInstr*>* await_joins() const {
     return await_joins_;
   }
 
   void AddCatchEntry(CatchBlockEntryInstr* entry);
 
   intptr_t num_copied_params() const {
     return num_copied_params_;
   }
   intptr_t num_non_copied_params() const {
@@ skipping 69 matching lines @@
 
   // A stack of enclosing nested statements.
   NestedStatement* nesting_stack_;
 
   // The deopt id of the OSR entry or Isolate::kNoDeoptId if not compiling
   // for OSR.
   const intptr_t osr_id_;
 
   intptr_t jump_count_;
   ZoneGrowableArray<JoinEntryInstr*>* await_joins_;
-  ZoneGrowableArray<intptr_t>* await_levels_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(FlowGraphBuilder);
 };
 
 
 // Translate an AstNode to a control-flow graph fragment for its effects
 // (e.g., a statement or an expression in an effect context).  Implements a
 // function from an AstNode and next temporary index to a graph fragment
 // with a single entry and at most one exit.  The fragment is represented by
 // an (entry, exit) pair of Instruction pointers:
@@ skipping 190 matching lines @@
                         const AbstractType& dst_type,
                         const String& dst_name);
 
   // Helpers for allocating and deallocating temporary locals on top of the
   // expression stack.
   LocalVariable* EnterTempLocalScope(Value* value);
   Definition* ExitTempLocalScope(LocalVariable* var);
 
   void BuildLetTempExpressions(LetNode* node);
 
-  void BuildSyncYieldJump(LocalVariable* old_context,
-                          LocalVariable* iterator_param,
-                          const intptr_t old_ctx_level,
-                          JoinEntryInstr* target);
-
-  void BuildAsyncJump(LocalVariable* old_context,
-                      LocalVariable* continuation_result,
-                      LocalVariable* continuation_error,
-                      LocalVariable* continuation_stack_trace,
-                      const intptr_t old_ctx_level,
-                      JoinEntryInstr* target);
-
   void BuildInstanceGetterConditional(InstanceGetterNode* node);
   void BuildInstanceCallConditional(InstanceCallNode* node);
 
   Isolate* isolate() const { return owner()->isolate(); }
   Zone* zone() const { return owner()->zone(); }
 
  private:
   friend class TempLocalScope;  // For ReturnDefinition.
 
   // Helper to drop the result value.
@@ skipping 124 matching lines @@
   // Output parameters.
   GrowableArray<TargetEntryInstr**> true_successor_addresses_;
   GrowableArray<TargetEntryInstr**> false_successor_addresses_;
 
   intptr_t condition_token_pos_;
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_BUILDER_H_