Fix a bug in instance canonicalization and add debug mode checks that we are not missing any fields.

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 9184 matching lines @@
       if ((*reinterpret_cast<RawObject**>(this_addr + offset)) !=
           (*reinterpret_cast<RawObject**>(other_addr + offset))) {
         return false;
       }
     }
   }
   return true;
 }
 
 
+#if defined(DEBUG)
+class CheckForPointers : public ObjectPointerVisitor {
+ public:
+  explicit CheckForPointers(Isolate* isolate)
+      : ObjectPointerVisitor(isolate), has_pointers_(false) {}
+
+  bool has_pointers() const { return has_pointers_; }
+
+  void VisitPointers(RawObject** first, RawObject** last) {
+    if (first != last) {
+      has_pointers_ = true;
+    }
+  }
+
+ private:
+  bool has_pointers_;
+
+  DISALLOW_COPY_AND_ASSIGN(CheckForPointers);
+};
+#endif  // DEBUG
+
+
 RawInstance* Instance::CheckAndCanonicalize(const char** error_str) const {
   ASSERT(!IsNull());
   if (this->IsCanonical()) {
     return this->raw();
   }
   Instance& result = Instance::Handle();
   const Class& cls = Class::Handle(this->clazz());
   // TODO(srdjan): Check that predefined classes do not have fields that need
   // to be checked/canonicalized as well.
-  if ((cls.id() >= kNumPredefinedCids) || cls.IsArray()) {
+  if ((cls.id() >= kNumPredefinedCids) || IsArray()) {
     // Iterate over all fields, canonicalize numbers and strings, expect all
     // other instances to be canonical otherwise report error (return
     // Instance::null()).
     Object& obj = Object::Handle();
     const intptr_t end_field_offset = cls.instance_size() - kWordSize;

[siva, 2013/06/14 21:04:03]

cls.instance_size() is not the right size for ObjectArray.
You would have to do Array::InstanceSize(length) to get the
right size.

[srdjan, 2013/06/14 21:43:45]

Done.

     for (intptr_t field_offset = 0;
          field_offset <= end_field_offset;
          field_offset += kWordSize) {
       obj = *this->FieldAddrAtOffset(field_offset);
       if (obj.IsInstance() && !obj.IsSmi() && !obj.IsCanonical()) {
         if (obj.IsNumber() || obj.IsString()) {
           obj = Instance::Cast(obj).CheckAndCanonicalize(NULL);
           ASSERT(!obj.IsNull());
           this->SetFieldAtOffset(field_offset, obj);
         } else {
           ASSERT(error_str != NULL);
           const char* kFormat = "field: %s\n";
           const intptr_t len =
               OS::SNPrint(NULL, 0, kFormat, obj.ToCString()) + 1;
           char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
           OS::SNPrint(chars, len, kFormat, obj.ToCString());
           *error_str = chars;
           return Instance::null();
         }
       }
     }
+  } else {
+#if defined(DEBUG)
+    // Make sure that we are not missing any fields.
+    CheckForPointers has_pointers(Isolate::Current());
+    this->raw()->VisitPointers(&has_pointers);
+    ASSERT(!has_pointers.has_pointers());
+#endif  // DEBUG
   }
   Array& constants = Array::Handle(cls.constants());
   const intptr_t constants_len = constants.Length();
   // Linear search to see whether this value is already present in the
   // list of canonicalized constants.
   intptr_t index = 0;
   while (index < constants_len) {
     result ^= constants.At(index);
     if (result.IsNull()) {
       break;
@@ skipping 4288 matching lines @@
                                     space);
   return reinterpret_cast<RawWeakProperty*>(raw);
 }
 
 
 const char* WeakProperty::ToCString() const {
   return "_WeakProperty";
 }
 
 }  // namespace dart