Changes to prepare for allowing script snapshots to be taken after running the main application

runtime/vm/raw_object_snapshot.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 "vm/object_store.h"
 #include "vm/snapshot.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 #include "vm/visitor.h"
 
 namespace dart {
 
+DECLARE_FLAG(int, optimization_counter_threshold);
+
 #define NEW_OBJECT(type)                                                       \
   ((kind == Snapshot::kFull) ? reader->New##type() : type::New())
 
 #define NEW_OBJECT_WITH_LEN(type, len)                                         \
   ((kind == Snapshot::kFull) ? reader->New##type(len) : type::New(len))
 
 #define NEW_OBJECT_WITH_LEN_SPACE(type, len, kind)                             \
   ((kind == Snapshot::kFull) ?                                                 \
   reader->New##type(len) : type::New(len, HEAP_SPACE(kind)))
 
@@ skipping 707 matching lines @@
   // Write out the serialization header value for this object.
   writer->WriteInlinedObjectHeader(object_id);
 
   // Write out the class and tags information.
   writer->WriteVMIsolateObject(kFunctionCid);
   writer->WriteTags(writer->GetObjectTags(this));
 
   // Write out all the non object fields.
   writer->Write<int32_t>(ptr()->token_pos_);
   writer->Write<int32_t>(ptr()->end_token_pos_);
-  writer->Write<int32_t>(ptr()->usage_counter_);
+  if (Code::IsOptimized(ptr()->instructions_->ptr()->code_)) {
+    writer->Write<int32_t>(FLAG_optimization_counter_threshold);
+  } else {
+    writer->Write<int32_t>(0);
+  }
   writer->Write<int16_t>(ptr()->num_fixed_parameters_);
   writer->Write<int16_t>(ptr()->num_optional_parameters_);
   writer->Write<int16_t>(ptr()->deoptimization_counter_);
   writer->Write<uint32_t>(ptr()->kind_tag_);
   writer->Write<uint16_t>(ptr()->optimized_instruction_count_);
   writer->Write<uint16_t>(ptr()->optimized_call_site_count_);
 
   // Write out all the object pointer fields.
   SnapshotWriterVisitor visitor(writer);
   visitor.VisitPointers(from(), writer->snapshot_code() ? to()
@@ skipping 275 matching lines @@
                             is_in_fullsnapshot);
     // The native resolver and symbolizer are not serialized.
     library.set_native_entry_resolver(NULL);
     library.set_native_entry_symbol_resolver(NULL);
     // The cache of loaded scripts is not serialized.
     library.StorePointer(&library.raw_ptr()->loaded_scripts_, Array::null());
 
     // Set all the object fields.
     // TODO(5411462): Need to assert No GC can happen here, even though
     // allocations may happen.
-    intptr_t num_flds = (library.raw()->to() - library.raw()->from());
+    RawObject** toobj = (kind == Snapshot::kFull) ?
+        library.raw()->to() : library.raw()->to_snapshot();
+    intptr_t num_flds = (toobj - library.raw()->from());
     for (intptr_t i = 0; i <= num_flds; i++) {
       (*reader->PassiveObjectHandle()) = reader->ReadObjectImpl(kAsReference);
       library.StorePointer((library.raw()->from() + i),
                            reader->PassiveObjectHandle()->raw());
     }
     if (kind != Snapshot::kFull) {
+      // The cache of resolved names in library scope is not serialized.
+      const intptr_t kInitialNameCacheSize = 64;
+      library.InitResolvedNamesCache(kInitialNameCacheSize);
       library.Register();
     }
   }
   return library.raw();
 }
 
 
 void RawLibrary::WriteTo(SnapshotWriter* writer,
                          intptr_t object_id,
                          Snapshot::Kind kind) {
@@ skipping 25 matching lines @@
     writer->Write<bool>(ptr()->corelib_imported_);
     writer->Write<bool>(ptr()->is_dart_scheme_);
     writer->Write<bool>(ptr()->debuggable_);
     // We do not serialize the native resolver or symbolizer. These need to be
     // explicitly set after deserialization.
     // We do not write the loaded_scripts_ cache to the snapshot. It gets
     // set to NULL when reading the library from the snapshot, and will
     // be rebuilt lazily.
 
     // Write out all the object pointer fields.
+    RawObject** toobj = (kind == Snapshot::kFull) ? to() : to_snapshot();
     SnapshotWriterVisitor visitor(writer);
-    visitor.VisitPointers(from(), to());
+    visitor.VisitPointers(from(), toobj);
   }
 }
 
 
 RawLibraryPrefix* LibraryPrefix::ReadFrom(SnapshotReader* reader,
                                           intptr_t object_id,
                                           intptr_t tags,
                                           Snapshot::Kind kind) {
   ASSERT(reader != NULL);
   ASSERT((kind == Snapshot::kScript) || (kind == Snapshot::kFull));
@@ skipping 2204 matching lines @@
     // We do not allow objects with native fields in an isolate message.
     writer->SetWriteException(Exceptions::kArgument,
                               "Illegal argument in isolate message"
                               " : (object is a UserTag)");
   } else {
     UNREACHABLE();
   }
 }
 
 }  // namespace dart