ART: Balanced locking

Change the verifier to check for balanced locking. When balanced
locking can't be guaranteed, use a new failure kind to punt to
the interpreter.

Add smali tests, with JNI code to check the balanced-locking result.

Bug: 23502994
Change-Id: Icd7db0be20ef2f69f0ac784de43dcba990035cd8
diff --git a/test/088-monitor-verification/stack_inspect.cc b/test/088-monitor-verification/stack_inspect.cc
new file mode 100644
index 0000000..e2899c3
--- /dev/null
+++ b/test/088-monitor-verification/stack_inspect.cc
@@ -0,0 +1,81 @@
+/*
+ * 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 "jni.h"
+
+#include "base/logging.h"
+#include "dex_file-inl.h"
+#include "mirror/class-inl.h"
+#include "nth_caller_visitor.h"
+#include "runtime.h"
+#include "scoped_thread_state_change.h"
+#include "stack.h"
+#include "thread-inl.h"
+
+namespace art {
+
+// public static native void assertCallerIsInterpreted();
+
+extern "C" JNIEXPORT void JNICALL Java_Main_assertCallerIsInterpreted(JNIEnv* env, jclass) {
+  LOG(INFO) << "assertCallerIsInterpreted";
+
+  ScopedObjectAccess soa(env);
+  NthCallerVisitor caller(soa.Self(), 1, false);
+  caller.WalkStack();
+  CHECK(caller.caller != nullptr);
+  LOG(INFO) << PrettyMethod(caller.caller);
+  CHECK(caller.GetCurrentShadowFrame() != nullptr);
+}
+
+// public static native void assertCallerIsManaged();
+
+extern "C" JNIEXPORT void JNICALL Java_Main_assertCallerIsManaged(JNIEnv* env, jclass cls) {
+  // Note: needs some smarts to not fail if there is no managed code, at all.
+  LOG(INFO) << "assertCallerIsManaged";
+
+  ScopedObjectAccess soa(env);
+
+  mirror::Class* klass = soa.Decode<mirror::Class*>(cls);
+  const DexFile& dex_file = klass->GetDexFile();
+  const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile();
+  if (oat_dex_file == nullptr) {
+    // No oat file, this must be a test configuration that doesn't compile at all. Ignore that the
+    // result will be that we're running the interpreter.
+    return;
+  }
+
+  NthCallerVisitor caller(soa.Self(), 1, false);
+  caller.WalkStack();
+  CHECK(caller.caller != nullptr);
+  LOG(INFO) << PrettyMethod(caller.caller);
+
+  if (caller.GetCurrentShadowFrame() == nullptr) {
+    // Not a shadow frame, this looks good.
+    return;
+  }
+
+  // This could be an interpret-only or a verify-at-runtime compilation, or a read-barrier variant,
+  // or... It's not really safe to just reject now. Let's look at the access flags. If the method
+  // was successfully verified, its access flags should be set to mark it preverified, except when
+  // we're running soft-fail tests.
+  if (Runtime::Current()->IsVerificationSoftFail()) {
+    // Soft-fail config. Everything should be running with interpreter access checks, potentially.
+    return;
+  }
+  CHECK(caller.caller->IsPreverified());
+}
+
+}  // namespace art