[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 411 matching lines @@
   }
 
   // It's very important that recompiles do not alter the structure of the type
   // feedback vector. Verify that the structure fits the function literal.
   CHECK(!info->shared_info()->feedback_vector()->metadata()->SpecDiffersFrom(
       info->literal()->feedback_vector_spec()));
 }
 
 bool UseIgnition(CompilationInfo* info) {
   if (info->is_debug()) return false;
-  if (info->shared_info()->is_generator() && !FLAG_ignition_generators) {
-    return false;
+  if (info->shared_info()->is_resumable()) {
+    return FLAG_ignition_generators;
   }

[neis, 2016/05/11 09:45:16]

This looks wrong, it's not the same as

if (info->shared_info()->is_resumable() && !FLAG_ignition_generators) {
  return false;
}

so you are changing the logic by skipping the filter tests below.

 
   // 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.
   return info->shared_info()->PassesFilter(FLAG_ignition_filter);
 }
@@ skipping 1315 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