Walk internal ArtField/ArtMethod pointers

During structural class redefinition we sometimes need to update some
of the ArtMethod/ArtField pointers held by runtime frames. This adds
support for doing this through a StackReflectiveHandleScope similar to
the StackHandleScope used for holding object references. This also
updates various places where reflective-handles to ArtMethods and
ArtFields are needed, for example the JniIdManager, field Read/Write
operations and events, field resolution, and the old debugger.

Test: ./test.py --host
Bug: 134162467

Change-Id: I4ea73e85956a07735c6d7b125c5828a4233670bc

1 files changed, 71 insertions, 0 deletions

diff --git a/runtime/reflective_reference.h b/runtime/reflective_reference.h
new file mode 100644
index 0000000000..f57c0301bc
--- /dev/null
+++ b/runtime/reflective_reference.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_RUNTIME_REFLECTIVE_REFERENCE_H_
+#define ART_RUNTIME_REFLECTIVE_REFERENCE_H_
+
+#include "android-base/macros.h"
+#include "base/macros.h"
+#include "mirror/object_reference.h"
+
+namespace art {
+
+class ArtField;
+class ArtMethod;
+// A reference to a ArtField or ArtMethod.
+template <class ReflectiveType>
+class ReflectiveReference {
+ public:
+  static_assert(std::is_same_v<ReflectiveType, ArtMethod> ||
+                    std::is_same_v<ReflectiveType, ArtField>,
+                "Uknown type!");
+  ReflectiveReference() : val_(nullptr) {}
+  explicit ReflectiveReference(ReflectiveType* r) : val_(r) {}
+  ReflectiveReference<ReflectiveType>& operator=(const ReflectiveReference<ReflectiveType>& t) =
+      default;
+
+  ReflectiveType* Ptr() {
+    return val_;
+  }
+
+  void Assign(ReflectiveType* r) {
+    val_ = r;
+  }
+
+  bool IsNull() const {
+    return val_ == nullptr;
+  }
+
+  bool operator==(const ReflectiveReference<ReflectiveType>& rr) const {
+    return val_ == rr.val_;
+  }
+  bool operator!=(const ReflectiveReference<ReflectiveType>& rr) const {
+    return !operator==(rr);
+  }
+  bool operator==(std::nullptr_t) const {
+    return IsNull();
+  }
+  bool operator!=(std::nullptr_t) const {
+    return !IsNull();
+  }
+
+ private:
+  ReflectiveType* val_;
+};
+
+}  // namespace art
+
+#endif  // ART_RUNTIME_REFLECTIVE_REFERENCE_H_