Tweak liveness when instructions are used in environments.

Instructions remain live when debuggable, but only instructions
with object types remain live when non-debuggable.

Enable StackVisitor::GetThisObject for optimizing.

Change-Id: Id87b2cbf33a02450059acc9993995782e5f28987
diff --git a/test/461-get-reference-vreg/get_reference_vreg_jni.cc b/test/461-get-reference-vreg/get_reference_vreg_jni.cc
new file mode 100644
index 0000000..f0b78e1
--- /dev/null
+++ b/test/461-get-reference-vreg/get_reference_vreg_jni.cc
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include "arch/context.h"
+#include "jni.h"
+#include "mirror/art_method-inl.h"
+#include "scoped_thread_state_change.h"
+#include "stack.h"
+#include "thread.h"
+
+namespace art {
+
+namespace {
+
+class TestVisitor : public StackVisitor {
+ public:
+  TestVisitor(Thread* thread, Context* context, mirror::Object* this_value)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+      : StackVisitor(thread, context), this_value_(this_value), found_method_index_(0) {}
+
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    mirror::ArtMethod* m = GetMethod();
+    std::string m_name(m->GetName());
+
+    if (m_name.compare("testThisWithInstanceCall") == 0) {
+      found_method_index_ = 1;
+      uint32_t value = 0;
+      CHECK(GetVReg(m, 1, kReferenceVReg, &value));
+      CHECK_EQ(reinterpret_cast<mirror::Object*>(value), this_value_);
+      CHECK_EQ(GetThisObject(), this_value_);
+    } else if (m_name.compare("testThisWithStaticCall") == 0) {
+      found_method_index_ = 2;
+      uint32_t value = 0;
+      CHECK(GetVReg(m, 1, kReferenceVReg, &value));
+    } else if (m_name.compare("testParameter") == 0) {
+      found_method_index_ = 3;
+      uint32_t value = 0;
+      CHECK(GetVReg(m, 1, kReferenceVReg, &value));
+    } else if (m_name.compare("testObjectInScope") == 0) {
+      found_method_index_ = 4;
+      uint32_t value = 0;
+      CHECK(GetVReg(m, 0, kReferenceVReg, &value));
+    }
+
+    return true;
+  }
+
+  mirror::Object* this_value_;
+
+  // Value returned to Java to ensure the methods testSimpleVReg and testPairVReg
+  // have been found and tested.
+  jint found_method_index_;
+};
+
+extern "C" JNIEXPORT jint JNICALL Java_Main_doNativeCallRef(JNIEnv*, jobject value) {
+  ScopedObjectAccess soa(Thread::Current());
+  std::unique_ptr<Context> context(Context::Create());
+  TestVisitor visitor(soa.Self(), context.get(), soa.Decode<mirror::Object*>(value));
+  visitor.WalkStack();
+  return visitor.found_method_index_;
+}
+
+extern "C" JNIEXPORT jint JNICALL Java_Main_doStaticNativeCallRef(JNIEnv*, jclass) {
+  ScopedObjectAccess soa(Thread::Current());
+  std::unique_ptr<Context> context(Context::Create());
+  TestVisitor visitor(soa.Self(), context.get(), nullptr);
+  visitor.WalkStack();
+  return visitor.found_method_index_;
+}
+
+}  // namespace
+
+}  // namespace art