Merged String subclasses into String.

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/bigint_operations.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/snapshot.h"
 #include "vm/symbols.h"
 #include "vm/visitor.h"
@@ skipping 1610 matching lines @@
 
 void RawString::WriteTo(SnapshotWriter* writer,
                         intptr_t object_id,
                         Snapshot::Kind kind) {
   UNREACHABLE();  // String is an abstract class.
 }
 
 
 template<typename HandleType, typename CharacterType>
 void String::ReadFromImpl(SnapshotReader* reader,
-                          HandleType* str_obj,
+                          String* str_obj,
                           intptr_t len,
                           intptr_t tags,
                           Snapshot::Kind kind) {
   ASSERT(reader != NULL);
   if (RawObject::IsCanonical(tags)) {
     // Set up canonical string object.
     ASSERT(reader != NULL);
     CharacterType* ptr =
         Isolate::Current()->current_zone()->Alloc<CharacterType>(len);
     for (intptr_t i = 0; i < len; i++) {
       ptr[i] = reader->Read<CharacterType>();
     }
     *str_obj ^= Symbols::New(ptr, len);
   } else {
     // Set up the string object.
     *str_obj = HandleType::New(len, HEAP_SPACE(kind));
     str_obj->set_tags(tags);
     str_obj->SetHash(0);  // Will get computed when needed.
+    CharacterType* dst_chars =
+        const_cast<CharacterType*>(HandleType::CharAddr(*str_obj, 0));
     for (intptr_t i = 0; i < len; i++) {
-      *str_obj->CharAddr(i) = reader->Read<CharacterType>();
+      dst_chars[i] = reader->Read<CharacterType>();

[siva, 2012/11/02 01:15:25]

dst_chars is pointing to a raw pointer and we are looping through without any
NOGCScope here.

why not leave the loop as is, that should work right?  

[Tom Ball, 2012/11/02 23:31:50]

Restored original loop, updated it.

     }
   }
 }
 
 
 RawOneByteString* OneByteString::ReadFrom(SnapshotReader* reader,
                                           intptr_t object_id,
                                           intptr_t tags,
                                           Snapshot::Kind kind) {
   // Read the length so that we can determine instance size to allocate.
   ASSERT(reader != NULL);
   intptr_t len = reader->ReadSmiValue();
   intptr_t hash = reader->ReadSmiValue();
-  OneByteString& str_obj = OneByteString::ZoneHandle(reader->isolate(),
-                                                     OneByteString::null());
+  String& str_obj = OneByteString::ZoneHandle(reader->isolate(),

[siva, 2012/11/02 01:15:25]

Should be String::ZoneHandle(.....);

[Tom Ball, 2012/11/02 23:31:50]

Done.

+                                              String::null());
 
   if (kind == Snapshot::kFull) {
     ASSERT(reader->isolate()->no_gc_scope_depth() != 0);
     RawOneByteString* obj = reader->NewOneByteString(len);
     str_obj = obj;
     str_obj.set_tags(tags);
     obj->ptr()->hash_ = Smi::New(hash);
     if (len > 0) {
-      uint8_t* raw_ptr = str_obj.CharAddr(0);
+      uint8_t* raw_ptr =
+          const_cast<uint8_t*>(OneByteString::CharAddr(str_obj, 0));

[siva, 2012/11/02 01:15:25]

why is this const_cast needed?

[Tom Ball, 2012/11/02 23:31:50]

Removed.

       reader->ReadBytes(raw_ptr, len);
     }
     ASSERT((hash == 0) || (String::Hash(str_obj, 0, str_obj.Length()) == hash));
   } else {
     ReadFromImpl<OneByteString, uint8_t>(reader, &str_obj, len, tags, kind);
   }
   reader->AddBackRef(object_id, &str_obj, kIsDeserialized);
-  return str_obj.raw();
+  return reinterpret_cast<RawOneByteString*>(str_obj.raw());

[siva, 2012/11/02 01:15:25]

I am not sure how many places you are having to do this
kind of cast , it might make sense to have a
OneByteString::raw(str_obj);
which does the case inside and returns.

[Tom Ball, 2012/11/02 23:31:50]

Good idea -- done.

 }
 
 
 RawTwoByteString* TwoByteString::ReadFrom(SnapshotReader* reader,
                                           intptr_t object_id,
                                           intptr_t tags,
                                           Snapshot::Kind kind) {
   // Read the length so that we can determine instance size to allocate.
   ASSERT(reader != NULL);
   intptr_t len = reader->ReadSmiValue();
   intptr_t hash = reader->ReadSmiValue();
-  TwoByteString& str_obj = TwoByteString::ZoneHandle(reader->isolate(),
-                                                     TwoByteString::null());
+  String& str_obj = TwoByteString::ZoneHandle(reader->isolate(),

[siva, 2012/11/02 01:15:25]

Should be String::ZoneHandle(...);

[Tom Ball, 2012/11/02 23:31:50]

Done.

+                                              String::null());
 
   if (kind == Snapshot::kFull) {
     RawTwoByteString* obj = reader->NewTwoByteString(len);
     str_obj = obj;
     str_obj.set_tags(tags);
     obj->ptr()->hash_ = Smi::New(hash);
-    uint16_t* raw_ptr = (len > 0)? str_obj.CharAddr(0) : NULL;
+    uint16_t* raw_ptr = (len > 0)?
+        const_cast<uint16_t*>(TwoByteString::CharAddr(str_obj, 0)) : NULL;

[siva, 2012/11/02 01:15:25]

Why is this const_cast needed?

[Tom Ball, 2012/11/02 23:31:50]

Removed.

     for (intptr_t i = 0; i < len; i++) {
-      ASSERT(str_obj.CharAddr(i) == raw_ptr);  // Will trigger assertions.
+      // Will trigger assertions.
+      ASSERT(TwoByteString::CharAddr(str_obj, i) == raw_ptr);
       *raw_ptr = reader->Read<uint16_t>();
       raw_ptr += 1;
     }
     ASSERT(String::Hash(str_obj, 0, str_obj.Length()) == hash);
   } else {
     ReadFromImpl<TwoByteString, uint16_t>(reader, &str_obj, len, tags, kind);
   }
   reader->AddBackRef(object_id, &str_obj, kIsDeserialized);
-  return str_obj.raw();
+  return reinterpret_cast<RawTwoByteString*>(str_obj.raw());

[siva, 2012/11/02 01:15:25]

Ditto comment for TwoByteString::raw(str_obj);

[Tom Ball, 2012/11/02 23:31:50]

Done.

 }
 
 
 template<typename T>
 static void StringWriteTo(SnapshotWriter* writer,
                           intptr_t object_id,
                           Snapshot::Kind kind,
                           intptr_t class_id,
                           intptr_t tags,
                           RawSmi* length,
@@ skipping 509 matching lines @@
   // Write out the class and tags information.
   writer->WriteIndexedObject(kWeakPropertyCid);
   writer->WriteIntptrValue(writer->GetObjectTags(this));
 
   // Write out all the other fields.
   writer->Write<RawObject*>(ptr()->key_);
   writer->Write<RawObject*>(ptr()->value_);
 }
 
 }  // namespace dart