[esnext] prototype runtime implementation for async functions

src/compiler.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler.h"
 
 #include <algorithm>
 
 #include "src/ast/ast-numbering.h"
 #include "src/ast/prettyprinter.h"
@@ skipping 493 matching lines @@
       !(EnsureFeedbackVector(info), FullCodeGenerator::MakeCode(info))) {
     Isolate* isolate = info->isolate();
     if (!isolate->has_pending_exception()) isolate->StackOverflow();
     return false;
   }
   return true;
 }
 
 bool UseIgnition(CompilationInfo* info) {
   // TODO(4681): Generator functions are not yet supported.
-  if (info->shared_info()->is_generator()) {
+  if (info->shared_info()->is_generator() || info->shared_info()->is_async()) {
     return false;
   }
 
   // Checks whether top level functions should be passed by the filter.
   if (info->shared_info()->is_toplevel()) {
     Vector<const char> filter = CStrVector(FLAG_ignition_filter);
     return (filter.length() == 0) || (filter.length() == 1 && filter[0] == '*');
   }
 
   // Finally respect the filter.
@@ skipping 1138 matching lines @@
     MaybeHandle<Code> code;
     if (cached.code != nullptr) code = handle(cached.code);
     Handle<Context> native_context(function->context()->native_context());
     SharedFunctionInfo::AddToOptimizedCodeMap(shared, native_context, code,
                                               literals, BailoutId::None());
   }
 }
 
 }  // namespace internal
 }  // namespace v8