Revert "Revert "Revert "Revert "Add intrinsic for Reference.get()""""

Fixed TargetReg issue causing build failure for x86.
This reverts commit 9e82bd3f0ce9e5f5777bea2f752ff3e251d32f9f.

Change-Id: I7e6a526954467aaf68deeed999880dfe9aa5f06e
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 1436810..2e51cf8 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -54,6 +54,7 @@
 #include "mirror/object-inl.h"
 #include "mirror/object_array-inl.h"
 #include "mirror/proxy.h"
+#include "mirror/reference-inl.h"
 #include "mirror/stack_trace_element.h"
 #include "mirror/string-inl.h"
 #include "object_utils.h"
@@ -257,6 +258,13 @@
   java_lang_String->SetObjectSize(mirror::String::InstanceSize());
   java_lang_String->SetStatus(mirror::Class::kStatusResolved, self);
 
+  // Setup Reference.
+  Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle(
+      AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize())));
+  mirror::Reference::SetClass(java_lang_ref_Reference.Get());
+  java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize());
+  java_lang_ref_Reference->SetStatus(mirror::Class::kStatusResolved, self);
+
   // Create storage for root classes, save away our work so far (requires descriptors).
   class_roots_ = mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(),
                                                            kClassRootsMax);
@@ -267,6 +275,7 @@
   SetClassRoot(kObjectArrayClass, object_array_class.Get());
   SetClassRoot(kCharArrayClass, char_array_class.Get());
   SetClassRoot(kJavaLangString, java_lang_String.Get());
+  SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get());
 
   // Setup the primitive type classes.
   SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean));
@@ -461,8 +470,12 @@
   SetClassRoot(kJavaLangReflectProxy, java_lang_reflect_Proxy);
 
   // java.lang.ref classes need to be specially flagged, but otherwise are normal classes
-  mirror::Class* java_lang_ref_Reference = FindSystemClass(self, "Ljava/lang/ref/Reference;");
-  SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference);
+  // finish initializing Reference class
+  java_lang_ref_Reference->SetStatus(mirror::Class::kStatusNotReady, self);
+  mirror::Class* Reference_class = FindSystemClass(self, "Ljava/lang/ref/Reference;");
+  CHECK_EQ(java_lang_ref_Reference.Get(), Reference_class);
+  CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize());
+  CHECK_EQ(java_lang_ref_Reference->GetClassSize(), mirror::Reference::ClassSize());
   mirror::Class* java_lang_ref_FinalizerReference =
       FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;");
   java_lang_ref_FinalizerReference->SetAccessFlags(
@@ -1231,6 +1244,7 @@
   array_iftable_ = GetClassRoot(kObjectArrayClass)->GetIfTable();
   DCHECK(array_iftable_ == GetClassRoot(kBooleanArrayClass)->GetIfTable());
   // String class root was set above
+  mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference));
   mirror::ArtField::SetClass(GetClassRoot(kJavaLangReflectArtField));
   mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass));
   mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass));
@@ -1354,6 +1368,7 @@
 ClassLinker::~ClassLinker() {
   mirror::Class::ResetClass();
   mirror::String::ResetClass();
+  mirror::Reference::ResetClass();
   mirror::ArtField::ResetClass();
   mirror::ArtMethod::ResetClass();
   mirror::BooleanArray::ResetArrayClass();
@@ -1600,6 +1615,8 @@
       klass.Assign(GetClassRoot(kJavaLangClass));
     } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) {
       klass.Assign(GetClassRoot(kJavaLangString));
+    } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) {
+      klass.Assign(GetClassRoot(kJavaLangRefReference));
     } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) {
       klass.Assign(GetClassRoot(kJavaLangDexCache));
     } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtField;") == 0) {