Add a verification step which iterates over the heap and verifies that all canonical objects are co…

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/become.h"
@@ skipping 15289 matching lines @@
     } else {
       result ^= this->raw();
     }
     ASSERT(result.IsOld());
     result.SetCanonical();
     return cls.InsertCanonicalConstant(zone, result);
   }
 }
 
 
+#if defined(DEBUG)
+bool Instance::CheckIsCanonical(Thread* thread) const {
+  Zone* zone = thread->zone();
+  Isolate* isolate = thread->isolate();
+  Instance& result = Instance::Handle(zone);
+  const Class& cls = Class::Handle(zone, this->clazz());
+  SafepointMutexLocker ml(isolate->constant_canonicalization_mutex());
+  result ^= cls.LookupCanonicalInstance(zone, *this);
+  return (result.raw() == this->raw());
+}
+#endif  // DEBUG
+
+
 RawAbstractType* Instance::GetType() const {
   if (IsNull()) {
     return Type::NullType();
   }
   const Class& cls = Class::Handle(clazz());
   if (cls.IsClosureClass()) {
     const Function& signature =
         Function::Handle(Closure::Cast(*this).function());
     Type& type = Type::Handle(signature.SignatureType());
     if (type.type_class() == cls.raw()) {
@@ skipping 1788 matching lines @@
       type.SetCanonical();  // Mark object as being canonical.
       bool present = table.Insert(type);
       ASSERT(!present);
     }
     object_store->set_canonical_types(table.Release());
   }
   return type.raw();
 }
 
 
+#if defined(DEBUG)
+bool Type::CheckIsCanonical(Thread* thread) const {
+  if (IsMalformed()) {
+    return true;
+  }
+  if (type_class() == Object::dynamic_class()) {
+    return (raw() == Object::dynamic_type().raw());
+  }
+  Zone* zone = thread->zone();
+  Isolate* isolate = thread->isolate();
+  AbstractType& type = Type::Handle(zone);
+  const Class& cls = Class::Handle(zone, type_class());
+
+  // Fast canonical lookup/registry for simple types.
+  if (!cls.IsGeneric() && !cls.IsClosureClass() && !cls.IsTypedefClass()) {
+    ASSERT(!IsFunctionType());
+    type = cls.CanonicalType();
+    return (raw() == type.raw());
+  }
+
+  ObjectStore* object_store = isolate->object_store();
+  {
+    SafepointMutexLocker ml(isolate->type_canonicalization_mutex());
+    CanonicalTypeSet table(zone, object_store->canonical_types());
+    type ^= table.GetOrNull(CanonicalTypeKey(*this));
+    object_store->set_canonical_types(table.Release());
+  }
+  return (raw() == type.raw());
+}
+#endif  // DEBUG
+
+
 RawString* Type::EnumerateURIs() const {
   if (IsDynamicType() || IsVoidType()) {
     return Symbols::Empty().raw();
   }
   Thread* thread = Thread::Current();
   Zone* zone = thread->zone();
   GrowableHandlePtrArray<const String> pieces(zone, 6);
   if (IsFunctionType()) {
     // The scope class and type arguments do not appear explicitly in the user
     // visible name. The type arguments were used to instantiate the function
@@ skipping 242 matching lines @@
   }
   // TODO(regis): Try to reduce the number of nodes required to represent the
   // referenced recursive type.
   AbstractType& ref_type = AbstractType::Handle(type());
   ref_type = ref_type.Canonicalize(trail);
   set_type(ref_type);
   return raw();
 }
 
 
+#if defined(DEBUG)
+bool TypeRef::CheckIsCanonical(Thread* thread) const {
+  AbstractType& ref_type = AbstractType::Handle(type());
+  return ref_type.CheckIsCanonical(thread);
+}
+#endif  // DEBUG
+
+
 RawString* TypeRef::EnumerateURIs() const {
   Thread* thread = Thread::Current();
   Zone* zone = thread->zone();
   const AbstractType& ref_type = AbstractType::Handle(zone, type());
   ASSERT(!ref_type.IsDynamicType() && !ref_type.IsVoidType());
   GrowableHandlePtrArray<const String> pieces(zone, 6);
   const Class& cls = Class::Handle(zone, ref_type.type_class());
   pieces.Add(Symbols::TwoSpaces());
   pieces.Add(String::Handle(zone, cls.UserVisibleName()));
   // Break cycle by not printing type arguments, but '<optimized out>' instead.
@@ skipping 643 matching lines @@
                                           const char** error_str) const {
   intptr_t cid = GetClassId();
   switch (cid) {
     case kSmiCid:
       return reinterpret_cast<RawSmi*>(raw_value());
     case kMintCid:
       return Mint::NewCanonical(Mint::Cast(*this).value());
     case kDoubleCid:
       return Double::NewCanonical(Double::Cast(*this).value());
     case kBigintCid: {
+      if (this->IsCanonical()) {
+        return this->raw();
+      }
       Zone* zone = thread->zone();
       Isolate* isolate = thread->isolate();
-      if (!CheckAndCanonicalizeFields(thread, error_str)) {
-        return Instance::null();
-      }
       Bigint& result = Bigint::Handle(zone);
       const Class& cls = Class::Handle(zone, this->clazz());
       intptr_t index = 0;
       result ^= cls.LookupCanonicalBigint(zone, Bigint::Cast(*this), &index);
       if (!result.IsNull()) {
         return result.raw();
       }
       {
         SafepointMutexLocker ml(isolate->constant_canonicalization_mutex());
         // Retry lookup.
@@ skipping 19 matching lines @@
         return result.raw();
       }
     }
     default:
       UNREACHABLE();
   }
   return Instance::null();
 }
 
 
+#if defined(DEBUG)
+bool Number::CheckIsCanonical(Thread* thread) const {
+  intptr_t cid = GetClassId();
+  intptr_t idx = 0;
+  Zone* zone = thread->zone();
+  const Class& cls = Class::Handle(zone, this->clazz());
+  switch (cid) {
+    case kSmiCid:
+      return true;
+    case kMintCid: {
+      Mint& result = Mint::Handle(zone);
+      result ^= cls.LookupCanonicalMint(zone, Mint::Cast(*this).value(), &idx);
+      return (result.raw() == this->raw());
+    }
+    case kDoubleCid: {
+      Double& dbl = Double::Handle(zone);
+      dbl ^= cls.LookupCanonicalDouble(zone, Double::Cast(*this).value(), &idx);
+      return (dbl.raw() == this->raw());
+    }
+    case kBigintCid: {
+      Bigint& result = Bigint::Handle(zone);
+      result ^= cls.LookupCanonicalBigint(zone, Bigint::Cast(*this), &idx);
+      return (result.raw() == this->raw());
+    }
+    default:
+      UNREACHABLE();
+  }
+  return false;
+}
+#endif  // DEBUG
+
+
 const char* Number::ToCString() const {
   // Number is an interface. No instances of Number should exist.
   UNREACHABLE();
   return "Number";
 }
 
 
 const char* Integer::ToCString() const {
   // Integer is an interface. No instances of Integer should exist except null.
   ASSERT(IsNull());
@@ skipping 1680 matching lines @@
 
 RawInstance* String::CheckAndCanonicalize(Thread* thread,
                                           const char** error_str) const {
   if (IsCanonical()) {
     return this->raw();
   }
   return Symbols::New(Thread::Current(), *this);
 }
 
 
+#if defined(DEBUG)
+bool String::CheckIsCanonical(Thread* thread) const {
+  Zone* zone = thread->zone();
+  const String& str = String::Handle(zone, Symbols::Lookup(thread, *this));
+  return (str.raw() == this->raw());
+}
+#endif  // DEBUG
+
+
 RawString* String::New(const char* cstr, Heap::Space space) {
   ASSERT(cstr != NULL);
   intptr_t array_len = strlen(cstr);
   const uint8_t* utf8_array = reinterpret_cast<const uint8_t*>(cstr);
   return String::FromUTF8(utf8_array, array_len, space);
 }
 
 
 RawString* String::FromUTF8(const uint8_t* utf8_array,
                             intptr_t array_len,
@@ skipping 1500 matching lines @@
   if (with_type_argument) {
     dest.SetTypeArguments(TypeArguments::Handle(GetTypeArguments()));
   }
 
   return dest.raw();
 }
 
 
 void Array::MakeImmutable() const {
   if (IsImmutable()) return;
+  ASSERT(!IsCanonical());
   NoSafepointScope no_safepoint;
   uword tags = raw_ptr()->tags_;
   uword old_tags;
   do {
     old_tags = tags;
     uword new_tags = RawObject::ClassIdTag::update(kImmutableArrayCid,
                                                    old_tags);
     tags = CompareAndSwapTags(old_tags, new_tags);
   } while (tags != old_tags);
 }
@@ skipping 1294 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart