Simplify VM internal representation of a mixin application clause (MixinAppType

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 27361)
+++ runtime/vm/object.cc	(working copy)
@@ -11593,13 +11593,33 @@
 }
 
 
+intptr_t MixinAppType::token_pos() const {
+  return Class::Handle(MixinAppAt(0)).token_pos();
+}
+
+
+intptr_t MixinAppType::Depth() const {
+  const Array& mixin_apps = Array::Handle(mixins());
+  return mixin_apps.Length();
+}
+
+
 RawString* MixinAppType::Name() const {
-  return String::New("MixinApplication");
+  return String::New("MixinAppType");
 }
 
 
 const char* MixinAppType::ToCString() const {
-  return "MixinAppType";
+  const char* format = "MixinAppType: super type: %s; first mixin app: %s";
+  const char* super_type_cstr = String::Handle(AbstractType::Handle(
+      SuperType()).Name()).ToCString();
+  const char* first_mixin_app_cstr = String::Handle(Class::Handle(
+      MixinAppAt(0)).Name()).ToCString();
+  intptr_t len = OS::SNPrint(
+      NULL, 0, format, super_type_cstr, first_mixin_app_cstr) + 1;
+  char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
+  OS::SNPrint(chars, len, format, super_type_cstr, first_mixin_app_cstr);
+  return chars;
 }
 
 
@@ -11608,16 +11628,23 @@
 }
 
 
-void MixinAppType::set_super_type(const AbstractType& value) const {
-  StorePointer(&raw_ptr()->super_type_, value.raw());
+RawAbstractType* MixinAppType::SuperType() const {
+  return Class::Handle(MixinAppAt(0)).super_type();
 }
 
 
-void MixinAppType::set_mixin_types(const Array& value) const {
-  StorePointer(&raw_ptr()->mixin_types_, value.raw());
+RawClass* MixinAppType::MixinAppAt(intptr_t depth) const {
+  Class& mixin_app = Class::Handle();
+  mixin_app ^= Array::Handle(mixins()).At(depth);
+  return mixin_app.raw();
 }
 
 
+void MixinAppType::set_mixins(const Array& value) const {
+  StorePointer(&raw_ptr()->mixins_, value.raw());
+}
+
+
 RawMixinAppType* MixinAppType::New() {
   ASSERT(Isolate::Current()->object_store()->mixin_app_type_class() !=
          Class::null());
@@ -11630,11 +11657,9 @@
 }
 
 
-RawMixinAppType* MixinAppType::New(const AbstractType& super_type,
-                                   const Array& mixin_types) {
+RawMixinAppType* MixinAppType::New(const Array& mixins) {
   const MixinAppType& result = MixinAppType::Handle(MixinAppType::New());
-  result.set_super_type(super_type);
-  result.set_mixin_types(mixin_types);
+  result.set_mixins(mixins);
   return result.raw();
 }