Create only one closure for the body of an async* function.

runtime/vm/parser.cc

 // 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.
 
 #include "vm/parser.h"
 
 #include "lib/invocation_mirror.h"
 #include "platform/utils.h"
 #include "vm/ast_transformer.h"
 #include "vm/bootstrap.h"
@@ skipping 6718 matching lines @@
 // Generate the Ast nodes for the implicit code of the async* function.
 //
 // f(...) async* {
 //   var :controller;
 //   var :await_jump_var = -1;
 //   var :await_context_var;
 //   f_async_body() {
 //     ... source code of f ...
 //   }
 //   var :async_op = f_async_body;
-//   :controller = new _AsyncStarStreamController(f_async_body);
+//   :controller = new _AsyncStarStreamController(:async_op);
 //   return :controller.stream;
 // }
-SequenceNode* Parser::CloseAsyncGeneratorFunction(const Function& closure,
+SequenceNode* Parser::CloseAsyncGeneratorFunction(const Function& closure_func,
                                                   SequenceNode* closure_body) {
   TRACE_PARSER("CloseAsyncGeneratorFunction");
-  ASSERT(!closure.IsNull());
+  ASSERT(!closure_func.IsNull());
   ASSERT(closure_body != NULL);
 
   // The block for the async closure body has already been closed. Close the
   // corresponding function block.
   CloseBlock();
 
   // Make sure the implicit variables of the async generator function
   // are captured.
   closure_body->scope()->LookupVariable(Symbols::AwaitJumpVar(), false);
   closure_body->scope()->LookupVariable(Symbols::AwaitContextVar(), false);
@@ skipping 12 matching lines @@
       current_block_->scope->LookupVariable(Symbols::AwaitJumpVar(), false);
   LiteralNode* init_value =
       new(Z) LiteralNode(Scanner::kNoSourcePos, Smi::ZoneHandle(Smi::New(-1)));
   current_block_->statements->Add(
       new(Z) StoreLocalNode(Scanner::kNoSourcePos, jump_var, init_value));
 
   // Add to AST:
   //   :async_op = <closure>;  (containing the original body)
   LocalVariable* async_op_var =
       current_block_->scope->LookupVariable(Symbols::AsyncOperation(), false);
-  ClosureNode* cn = new(Z) ClosureNode(
-      Scanner::kNoSourcePos, closure, NULL, closure_body->scope());
+  ClosureNode* closure_obj = new(Z) ClosureNode(
+      Scanner::kNoSourcePos, closure_func, NULL, closure_body->scope());
   StoreLocalNode* store_async_op = new (Z) StoreLocalNode(
       Scanner::kNoSourcePos,
       async_op_var,
-      cn);
+      closure_obj);
   current_block_->statements->Add(store_async_op);
 
   // :controller = new _AsyncStarStreamController(body_closure);
   ArgumentListNode* arguments = new(Z) ArgumentListNode(Scanner::kNoSourcePos);
-  ClosureNode* closure_obj = new(Z) ClosureNode(
-      Scanner::kNoSourcePos, closure, NULL, closure_body->scope());
-  arguments->Add(closure_obj);
+  arguments->Add(new (Z) LoadLocalNode(Scanner::kNoSourcePos, async_op_var));
   ConstructorCallNode* controller_constructor_call =
       new(Z) ConstructorCallNode(Scanner::kNoSourcePos,
                                  TypeArguments::ZoneHandle(Z),
                                  controller_constructor,
                                  arguments);
   LocalVariable* controller_var =
      current_block_->scope->LookupVariable(Symbols::Controller(), false);
   StoreLocalNode* store_controller =
       new(Z) StoreLocalNode(Scanner::kNoSourcePos,
                             controller_var,
@@ skipping 6826 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart