Incremental changes from background compilation work

runtime/vm/object.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/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 9573 matching lines @@
 
 
 // Returns true if the name is found in the cache, false no cache hit.
 // obj is set to the cached entry. It may be null, indicating that the
 // name does not resolve to anything in this library.
 bool Library::LookupResolvedNamesCache(const String& name,
                                        Object* obj) const {
   ResolvedNamesMap cache(resolved_names());
   bool present = false;
   *obj = cache.GetOrNull(name, &present);
-  ASSERT(cache.Release().raw() == resolved_names());
+  // Mutator compiler thread may add entries and therefore
+  // change 'resolved_names()' while running a background compilation;
+  // do not ASSERT that 'resolved_names()' has not changed.

[siva, 2015/12/22 19:43:46]

The background compiler will only add entries and not remove them, maybe there
is a way of asserting that, currently count_ is not exposed by hash map. We
could expose it and store old_count initially and then
add an assert to ensure the count doesn't become less than old_count.

[srdjan, 2015/12/22 20:23:10]

I agreed with you originally, but realized that the count is tied to the local
stack object, not to the array. Not doing anything for the moment.

+  cache.Release();
   return present;
 }
 
 
 // Add a name to the resolved name cache. This name resolves to the
 // given object in this library scope. obj may be null, which means
 // the name does not resolve to anything in this library scope.
 void Library::AddToResolvedNamesCache(const String& name,
                                       const Object& obj) const {
   if (!FLAG_use_lib_cache) {
@@ skipping 12388 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart