[vm/async] Make async transformer use typed variables, make async patch use function types

This gets rid of a slow AssertAssignable (function type test)
in _asyncThenWrapperHelper/_awaitHelper, which currently falls back to the slow table
search:

  AssertAssignable
    ^--> TypeTestingStub
          ^--> SlowTypeTestStub
               ^--> Subtype6TestCacheStub

Issue #37668

Change-Id: I3b6517b7e348e39619e8096d6ac2a4b179bb3242
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142022
Commit-Queue: Martin Kustermann <[email protected]>
Reviewed-by: Alexander Markov <[email protected]>
Reviewed-by: Clement Skau <[email protected]>

Author: mkustermann

pkg/front_end/lib/src/fasta/source/source_loader.dart

@@ -1386,6 +1386,8 @@ class _AsyncAwaitCompleter implements Completer {
   complete([value]) {}
 
   completeError(error, [stackTrace]) {}
+
+  void start(void Function() f) {}
 }
 
 class Stream {}

pkg/front_end/testcases/extensions/deferred_explicit_access.dart.strong.transformed.expect

@@ -18,8 +18,8 @@ static method main() → dynamic /* originally async */ {
   final asy::_AsyncAwaitCompleter<dynamic>* :async_completer = new asy::_AsyncAwaitCompleter::•<dynamic>();
   asy::FutureOr<dynamic>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -41,13 +41,13 @@ static method main() → dynamic /* originally async */ {
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }
 static method expect(dynamic expected, dynamic actual) → dynamic {

pkg/front_end/testcases/extensions/deferred_import_hidden.dart.strong.transformed.expect

@@ -10,8 +10,8 @@ static method main() → dynamic /* originally async */ {
   final asy::_AsyncAwaitCompleter<dynamic>* :async_completer = new asy::_AsyncAwaitCompleter::•<dynamic>();
   asy::FutureOr<dynamic>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -32,13 +32,13 @@ static method main() → dynamic /* originally async */ {
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }
 static method expect(dynamic expected, dynamic actual) → dynamic {

pkg/front_end/testcases/general/async_function.dart.strong.transformed.expect

@@ -11,8 +11,8 @@ static method asyncString() → asy::Future<core::String*>* /* originally async
   final asy::_AsyncAwaitCompleter<core::String*>* :async_completer = new asy::_AsyncAwaitCompleter::•<core::String*>();
   asy::FutureOr<core::String*>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   function :async_op([dynamic :result, dynamic :exception, dynamic :stack_trace]) → dynamic yielding 
@@ -25,21 +25,21 @@ static method asyncString() → asy::Future<core::String*>* /* originally async
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }
 static method asyncString2() → asy::Future<core::String*>* /* originally async */ {
   final asy::_AsyncAwaitCompleter<core::String*>* :async_completer = new asy::_AsyncAwaitCompleter::•<core::String*>();
   asy::FutureOr<core::String*>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   function :async_op([dynamic :result, dynamic :exception, dynamic :stack_trace]) → dynamic yielding 
@@ -52,13 +52,13 @@ static method asyncString2() → asy::Future<core::String*>* /* originally async
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }
 static method syncStarString() → core::Iterable<core::String*>* /* originally sync* */ {
@@ -101,8 +101,8 @@ static method asyncStarString() → asy::Stream<core::String*>* /* originally as
   asy::_AsyncStarStreamController<core::String*>* :controller;
   dynamic :controller_stream;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -128,7 +128,7 @@ static method asyncStarString() → asy::Stream<core::String*>* /* originally as
         }
         return;
       }
-      on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+      on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
         :controller.{asy::_AsyncStarStreamController::addError}(:exception, :stack_trace);
       }
     finally {
@@ -145,8 +145,8 @@ static method asyncStarString2() → asy::Stream<core::String*>* /* originally a
   asy::_AsyncStarStreamController<core::String*>* :controller;
   dynamic :controller_stream;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -163,7 +163,7 @@ static method asyncStarString2() → asy::Stream<core::String*>* /* originally a
         }
         return;
       }
-      on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+      on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
         :controller.{asy::_AsyncStarStreamController::addError}(:exception, :stack_trace);
       }
     finally {
@@ -180,8 +180,8 @@ static method main() → dynamic /* originally async */ {
   final asy::_AsyncAwaitCompleter<dynamic>* :async_completer = new asy::_AsyncAwaitCompleter::•<dynamic>();
   asy::FutureOr<dynamic>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -195,12 +195,12 @@ static method main() → dynamic /* originally async */ {
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }

pkg/front_end/testcases/general/async_nested.dart.strong.transformed.expect

@@ -22,8 +22,8 @@ static method main() → void /* originally async */ {
   final asy::_AsyncAwaitCompleter<dynamic>* :async_completer = new asy::_AsyncAwaitCompleter::•<dynamic>();
   asy::FutureOr<dynamic>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -56,13 +56,13 @@ static method main() → void /* originally async */ {
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }
 

pkg/front_end/testcases/general/await.dart.strong.transformed.expect

@@ -8,8 +8,8 @@ static method main() → dynamic /* originally async */ {
   final asy::_AsyncAwaitCompleter<dynamic>* :async_completer = new asy::_AsyncAwaitCompleter::•<dynamic>();
   asy::FutureOr<dynamic>* :return_value;
   dynamic :async_stack_trace;
-  dynamic :async_op_then;
-  dynamic :async_op_error;
+  (dynamic) →* asy::FutureOr<dynamic>* :async_op_then;
+  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
   core::int* :await_jump_var = 0;
   dynamic :await_ctx_var;
   dynamic :saved_try_context_var0;
@@ -23,12 +23,12 @@ static method main() → dynamic /* originally async */ {
       asy::_completeOnAsyncReturn(:async_completer, :return_value);
       return;
     }
-    on dynamic catch(dynamic :exception, dynamic :stack_trace) {
+    on dynamic catch(dynamic :exception, core::StackTrace* :stack_trace) {
       :async_completer.{asy::Completer::completeError}(:exception, :stack_trace);
     }
   :async_stack_trace = asy::_asyncStackTraceHelper(:async_op);
   :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
   :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
-  :async_completer.start(:async_op);
+  :async_completer.{asy::_AsyncAwaitCompleter::start}(:async_op);
   return :async_completer.{asy::Completer::future};
 }