Fraction class prototype and test (not to be committed).

runtime/vm/clustered_snapshot.cc

Index: runtime/vm/clustered_snapshot.cc
diff --git a/runtime/vm/clustered_snapshot.cc b/runtime/vm/clustered_snapshot.cc
index 6f958fd5cb3693e34ccef21399d6f54f3788b0c4..6a6bd11634061b1e453aad7ef8d2983a13ae5cfe 100644
--- a/runtime/vm/clustered_snapshot.cc
+++ b/runtime/vm/clustered_snapshot.cc
@@ -3278,6 +3278,84 @@ class BigintDeserializationCluster : public DeserializationCluster {
 };
 
 
+class FractionSerializationCluster : public SerializationCluster {
+ public:
+  FractionSerializationCluster() { }
+  virtual ~FractionSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawFraction* fraction = Fraction::RawCast(object);
+    objects_.Add(fraction);
+
+    RawObject** from = fraction->from();
+    RawObject** to = fraction->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kFractionCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawFraction* fraction = objects_[i];
+      s->AssignRef(fraction);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawFraction* fraction = objects_[i];
+      s->Write<bool>(fraction->IsCanonical());
+      RawObject** from = fraction->from();
+      RawObject** to = fraction->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawFraction*> objects_;
+};
+
+
+class FractionDeserializationCluster : public DeserializationCluster {
+ public:
+  FractionDeserializationCluster() { }
+  virtual ~FractionDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Fraction::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawFraction* fraction = reinterpret_cast<RawFraction*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(fraction, kFractionCid,
+                                     Fraction::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      RawObject** from = fraction->from();
+      RawObject** to = fraction->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+
 class DoubleSerializationCluster : public SerializationCluster {
  public:
   DoubleSerializationCluster() { }
@@ -4198,6 +4276,7 @@ SerializationCluster* Serializer::NewClusterForClass(intptr_t cid) {
     case kClosureCid: return new (Z) ClosureSerializationCluster();
     case kMintCid: return new (Z) MintSerializationCluster();
     case kBigintCid: return new (Z) BigintSerializationCluster();
+    case kFractionCid: return new (Z) FractionSerializationCluster();
     case kDoubleCid: return new (Z) DoubleSerializationCluster();
     case kGrowableObjectArrayCid:
       return new (Z) GrowableObjectArraySerializationCluster();
@@ -4521,6 +4600,7 @@ DeserializationCluster* Deserializer::ReadCluster() {
     case kClosureCid: return new (Z) ClosureDeserializationCluster();
     case kMintCid: return new (Z) MintDeserializationCluster();
     case kBigintCid: return new (Z) BigintDeserializationCluster();
+    case kFractionCid: return new (Z) FractionDeserializationCluster();
     case kDoubleCid: return new (Z) DoubleDeserializationCluster();
     case kGrowableObjectArrayCid:
       return new (Z) GrowableObjectArrayDeserializationCluster();