Simplify reload error reporting

runtime/vm/isolate_reload.cc

 // Copyright (c) 2016, 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/isolate_reload.h"
 
 #include "vm/become.h"
 #include "vm/bit_vector.h"
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
@@ skipping 30 matching lines @@
 #define I (isolate())
 #define Z (thread->zone())
 
 #define TIMELINE_SCOPE(name)                                                   \
     TimelineDurationScope tds##name(Thread::Current(),                         \
                                    Timeline::GetIsolateStream(),               \
                                    #name)
 
 
 InstanceMorpher::InstanceMorpher(Zone* zone, const Class& from, const Class& to)
-  : from_(from), to_(to), mapping_() {
+  : from_(from), to_(to), mapping_(zone, 0) {
   ComputeMapping();
-  before_ = new ZoneGrowableArray<const Instance*>(zone, 0);
-  after_ = new ZoneGrowableArray<const Instance*>(zone, 0);
+  before_ = new(zone) ZoneGrowableArray<const Instance*>(zone, 0);
+  after_ = new(zone) ZoneGrowableArray<const Instance*>(zone, 0);
   ASSERT(from_.id() == to_.id());
   cid_ = from_.id();
 }
 
 
 void InstanceMorpher::AddObject(RawObject* object) const {
   ASSERT(object->GetClassId() == cid());
   const Instance& instance = Instance::Cast(Object::Handle(object));
   before_->Add(&instance);
 }
@@ skipping 297 matching lines @@
     : zone_(Thread::Current()->zone()),
       start_time_micros_(OS::GetCurrentMonotonicMicros()),
       reload_timestamp_(OS::GetCurrentTimeMillis()),
       isolate_(isolate),
       reload_skipped_(false),
       reload_aborted_(false),
       js_(js),
       saved_num_cids_(-1),
       saved_class_table_(NULL),
       num_saved_libs_(-1),
-      instance_morphers_(),
-      reasons_to_cancel_reload_(),
+      instance_morphers_(zone_, 0),
+      reasons_to_cancel_reload_(zone_, 0),
       cid_mapper_(),
       modified_libs_(NULL),
       script_uri_(String::null()),
       error_(Error::null()),
       old_classes_set_storage_(Array::null()),
       class_map_storage_(Array::null()),
       old_libraries_set_storage_(Array::null()),
       library_map_storage_(Array::null()),
       become_map_storage_(Array::null()),
       become_enum_mappings_(GrowableObjectArray::null()),
@@ skipping 92 matching lines @@
   {
     TransitionVMToNative transition(thread);
     Api::Scope api_scope(thread);
 
     Dart_Handle retval =
         (I->library_tag_handler())(Dart_kScriptTag,
                                    Api::NewHandle(thread, Library::null()),
                                    Api::NewHandle(thread, root_lib_url.raw()));
     result = Api::UnwrapHandle(retval);
   }
+  if (result.IsUnwindError()) {
+    // Ignore an unwind error because the isolate is dead.
+    return;
+  }
   if (result.IsError()) {
-    const Error& error = Error::Cast(result);
-    AddReasonForCancelling(new Aborted(zone_, error));
-    // We call report on JSON here because we won't ever execute
-    // FinalizeLoading.
-    ReportOnJSON(js_);
+    FinalizeFailedLoad(Error::Cast(result));
   }
 }
 
 
 void IsolateReloadContext::RegisterClass(const Class& new_cls) {
   const Class& old_cls = Class::Handle(OldClassOrNull(new_cls));
   if (old_cls.IsNull()) {
     I->class_table()->Register(new_cls);
 
     if (FLAG_identity_reload) {
@@ skipping 10 matching lines @@
   isolate()->class_table()->SetAt(old_cls.id(), new_cls.raw());
   if (!old_cls.is_enum_class()) {
     new_cls.CopyCanonicalConstants(old_cls);
   }
   new_cls.CopyCanonicalType(old_cls);
   AddBecomeMapping(old_cls, new_cls);
   AddClassMapping(new_cls, old_cls);
 }
 
 
-// FinalizeLoading will be called *before* Reload() returns.
+// FinalizeLoading will be called *before* Reload() returns but will not be
+// called if the embedder fails to load sources.
 void IsolateReloadContext::FinalizeLoading() {
   if (reload_skipped_) {
     return;
   }
   BuildLibraryMapping();
   TIR_Print("---- DONE FINALIZING\n");
   if (ValidateReload()) {
     Commit();
     PostCommit();
     isolate()->set_last_reload_timestamp(reload_timestamp_);
   } else {
     ReportReasonsForCancelling();
     Rollback();
   }
   // ValidateReload mutates the direct subclass information and does
   // not remove dead subclasses.  Rebuild the direct subclass
   // information from scratch.
   RebuildDirectSubclasses();
 
-  BackgroundCompiler::Enable();
+  CommonFinalizeTail();
 }
 
 
+// FinalizeFailedLoad will be called *before* Reload() returns and will only
+// be called if the embedder fails to load sources.
+void IsolateReloadContext::FinalizeFailedLoad(const Error& error) {
+  AddReasonForCancelling(new Aborted(zone_, error));
+  ReportReasonsForCancelling();
+  Rollback();
+  CommonFinalizeTail();
+}
+
+
+void IsolateReloadContext::CommonFinalizeTail() {
+  BackgroundCompiler::Enable();
+  ReportOnJSON(js_);
+}
+
 void IsolateReloadContext::ReportOnJSON(JSONStream* stream) {
   JSONObject jsobj(stream);
   jsobj.AddProperty("type", "ReloadReport");
   jsobj.AddProperty("success", !HasReasonsForCancelling());
   {
     JSONObject details(&jsobj, "details");
     if (HasReasonsForCancelling()) {
       // Reload was rejected.
       JSONArray array(&jsobj, "notices");
       for (intptr_t i = 0; i < reasons_to_cancel_reload_.length(); i++) {
@@ skipping 12 matching lines @@
       details.AddProperty("finalLibraryCount", final_library_count);
       JSONArray array(&jsobj, "shapeChangeMappings");
       for (intptr_t i = 0; i < instance_morphers_.length(); i++) {
         instance_morphers_.At(i)->AppendTo(&array);
       }
     }
   }
 }
 
 
-void IsolateReloadContext::AbortReload(const Error& error) {
-  AddReasonForCancelling(new Aborted(zone_, error));
-  ReportReasonsForCancelling();
-  Rollback();
-}
-
-
 void IsolateReloadContext::EnsuredUnoptimizedCodeForStack() {
   TIMELINE_SCOPE(EnsuredUnoptimizedCodeForStack);
   StackFrameIterator it(StackFrameIterator::kDontValidateFrames);
 
   Function& func = Function::Handle();
   while (it.HasNextFrame()) {
     StackFrame* frame = it.NextFrame();
     if (frame->IsDartFrame()) {
       func = frame->LookupDartFunction();
       ASSERT(!func.IsNull());
@@ skipping 116 matching lines @@
 
   const GrowableObjectArray& libs =
       GrowableObjectArray::Handle(object_store()->libraries());
   Library& lib = Library::Handle();
   Array& scripts = Array::Handle();
   Script& script = Script::Handle();
   intptr_t num_libs = libs.Length();
 
   // Construct the imported-by graph.
   ZoneGrowableArray<ZoneGrowableArray<intptr_t>* >* imported_by =
-      new ZoneGrowableArray<ZoneGrowableArray<intptr_t>* >(zone_, num_libs);
+      new(zone_) ZoneGrowableArray<ZoneGrowableArray<intptr_t>* >(
+          zone_, num_libs);
   imported_by->SetLength(num_libs);
   for (intptr_t i = 0; i < num_libs; i++) {
-    (*imported_by)[i] = new ZoneGrowableArray<intptr_t>(zone_, 0);
+    (*imported_by)[i] = new(zone_) ZoneGrowableArray<intptr_t>(zone_, 0);
   }
   Array& ports = Array::Handle();
   Namespace& ns = Namespace::Handle();
   Library& target = Library::Handle();
 
   for (intptr_t lib_idx = 0; lib_idx < num_libs; lib_idx++) {
     lib ^= libs.At(lib_idx);
     ASSERT(lib_idx == lib.index());
     if (lib.is_dart_scheme()) {
       // We don't care about imports among dart scheme libraries.
@@ skipping 858 matching lines @@
         ASSERT(!super_cls.IsNull());
         super_cls.AddDirectSubclass(cls);
       }
     }
   }
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart