Fix async machinery (issue 22445 and possibly others to be triaged later).

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 39 matching lines @@
         default_parameter_values_(Array::ZoneHandle(zone(), Array::null())),
         current_context_var_(NULL),
         expression_temp_var_(NULL),
         finally_return_temp_var_(NULL),
         deferred_prefixes_(new ZoneGrowableArray<const LibraryPrefix*>()),
         guarded_fields_(new ZoneGrowableArray<const Field*>()),
         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(zone(), String::null())) {
+        have_seen_await_expr_(false) {
     ASSERT(function.IsZoneHandle());
     // Every function has a local variable for the current context.
     LocalVariable* temp = new(zone()) LocalVariable(
         function.token_pos(),
         Symbols::CurrentContextVar(),
         Type::ZoneHandle(zone(), Type::DynamicType()));
     ASSERT(temp != NULL);
     current_context_var_ = temp;
   }
 
@@ skipping 72 matching lines @@
     return (num_copied_params_ == 0)
         ? function().num_fixed_parameters() : 0;
   }
 
   void AllocateVariables();
   void AllocateIrregexpVariables(intptr_t num_stack_locals);
 
   void record_await() { have_seen_await_expr_ = true; }
   bool have_seen_await() const { return have_seen_await_expr_; }
 
-  void set_saved_try_ctx(LocalVariable* saved_try_ctx) {
-    ASSERT((saved_try_ctx == NULL) || !saved_try_ctx->is_captured());
-    saved_try_ctx_ = saved_try_ctx;
-  }
-  LocalVariable* saved_try_ctx() const { return saved_try_ctx_; }
-
-  void set_async_saved_try_ctx_name(const String& async_saved_try_ctx_name) {
-    async_saved_try_ctx_name_ = async_saved_try_ctx_name.raw();
-  }
-  RawString* async_saved_try_ctx_name() const {
-    return async_saved_try_ctx_name_.raw();
-  }
-
-  void reset_saved_try_ctx_vars() {
-    saved_try_ctx_ = NULL;
-    async_saved_try_ctx_name_ = String::null();
-  }
-
   Thread* thread() const { return thread_; }
   Isolate* isolate() const { return thread()->isolate(); }
   Zone* zone() const { return thread()->zone(); }
 
  private:
   Thread* thread_;
   const Function& function_;
   Code& code_;
   SequenceNode* node_sequence_;
   RegExpCompileData* regexp_compile_data_;
   LocalVariable* instantiator_;
   Array& default_parameter_values_;
   LocalVariable* current_context_var_;
   LocalVariable* expression_temp_var_;
   LocalVariable* finally_return_temp_var_;
   ZoneGrowableArray<const LibraryPrefix*>* deferred_prefixes_;
   ZoneGrowableArray<const Field*>* guarded_fields_;
 
   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_;
-  String& async_saved_try_ctx_name_;
 
   friend class Parser;
   DISALLOW_COPY_AND_ASSIGN(ParsedFunction);
 };
 
 
 class Parser : public ValueObject {
  public:
   // Parse the top level of a whole script file and register declared classes
   // in the given library.
@@ skipping 387 matching lines @@
   RawClass* CheckCaseExpressions(const GrowableArray<LiteralNode*>& values);
   CaseNode* ParseCaseClause(LocalVariable* switch_expr_value,
                             GrowableArray<LiteralNode*>* case_expr_values,
                             SourceLabel* case_label);
   AstNode* ParseSwitchStatement(String* label_name);
 
   // try/catch/finally parsing.
   void AddCatchParamsToScope(CatchParamDesc* exception_param,
                              CatchParamDesc* stack_trace_param,
                              LocalScope* scope);
-  void AddSavedExceptionAndStacktraceToScope(LocalVariable* exception_var,
-                                             LocalVariable* stack_trace_var,
-                                             LocalScope* scope);
+  void SetupSavedExceptionAndStacktrace();
+  void SaveExceptionAndStacktrace(LocalVariable* exception_var,
+                                  LocalVariable* stack_trace_var);
   // Parse all the catch clause of a try.
   SequenceNode* ParseCatchClauses(intptr_t handler_pos,
                                   LocalVariable* exception_var,
                                   LocalVariable* stack_trace_var,
                                   const GrowableObjectArray& handler_types,
                                   bool* needs_stack_trace);
   // Parse finally block and create an AST for it.
   SequenceNode* ParseFinallyBlock();
   // Adds try block to the list of try blocks seen so far.
   void PushTryBlock(Block* try_block);
   // Pops the inner most try block from the list.
   TryBlocks* PopTryBlock();
+  // Collect try block scopes and indices if await or yield is in try block.
+  void CheckAsyncOpInTryBlock(LocalScope** try_scope,
+                              int16_t* try_index,
+                              LocalScope** outer_try_scope,
+                              int16_t* outer_try_index) const;
   // Add specified node to try block list so that it can be patched with
   // inlined finally code if needed.
   void AddNodeForFinallyInlining(AstNode* node);
   // Add the inlined finally block to the specified node.
   void AddFinallyBlockToNode(AstNode* node, InlinedFinallyNode* finally_node);
   AstNode* ParseTryStatement(String* label_name);
   RawAbstractType* ParseConstFinalVarOrType(
       ClassFinalizer::FinalizationKind finalization);
   AstNode* ParseVariableDeclaration(const AbstractType& type,
                                     bool is_final,
@@ skipping 115 matching lines @@
   AstNode* ThrowTypeError(intptr_t type_pos, const AbstractType& type);
   AstNode* ThrowNoSuchMethodError(intptr_t call_pos,
                                   const Class& cls,
                                   const String& function_name,
                                   ArgumentListNode* function_arguments,
                                   InvocationMirror::Call call,
                                   InvocationMirror::Type type,
                                   const Function* func);
 
   void SetupSavedTryContext(LocalVariable* saved_try_context);
-  void RestoreSavedTryContext(LocalScope* saved_try_context_scope,
-                              int16_t try_index,
-                              SequenceNode* target);
 
   void CheckOperatorArity(const MemberDesc& member);
 
   void EnsureExpressionTemp();
   bool IsLegalAssignableSyntax(AstNode* expr, intptr_t end_pos);
   AstNode* CreateAssignmentNode(AstNode* original,
                                 AstNode* rhs,
                                 const String* left_ident,
                                 intptr_t left_pos);
   AstNode* InsertClosureCallNodes(AstNode* condition);
@@ skipping 76 matching lines @@
 
   // Indentation of parser trace.
   intptr_t trace_indent_;
 
   DISALLOW_COPY_AND_ASSIGN(Parser);
 };
 
 }  // namespace dart
 
 #endif  // VM_PARSER_H_