Use the caller's class loader when walking inlined frames.

We should not use the outer most class loader. JLS specification
is to use the caller's class loader.

Change-Id: I736f36c9b6a44fab213ad0c01cf1efc975b9b3a6

8 files changed, 221 insertions, 13 deletions

diff --git a/runtime/entrypoints/entrypoint_utils-inl.h b/runtime/entrypoints/entrypoint_utils-inl.h
index b0cbd02880..298b826307 100644
--- a/runtime/entrypoints/entrypoint_utils-inl.h
+++ b/runtime/entrypoints/entrypoint_utils-inl.h
@@ -39,9 +39,12 @@
 namespace art {
 
 inline ArtMethod* GetResolvedMethod(ArtMethod* outer_method,
-                                    uint32_t method_index,
-                                    InvokeType invoke_type)
+                                    const InlineInfo& inline_info,
+                                    uint8_t inlining_depth)
   SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+  uint32_t method_index = inline_info.GetMethodIndexAtDepth(inlining_depth);
+  InvokeType invoke_type = static_cast<InvokeType>(
+        inline_info.GetInvokeTypeAtDepth(inlining_depth));
   ArtMethod* caller = outer_method->GetDexCacheResolvedMethod(method_index, sizeof(void*));
   if (!caller->IsRuntimeMethod()) {
     return caller;
@@ -50,11 +53,20 @@ inline ArtMethod* GetResolvedMethod(ArtMethod* outer_method,
   // The method in the dex cache can be the runtime method responsible for invoking
   // the stub that will then update the dex cache. Therefore, we need to do the
   // resolution ourselves.
-
+  
+  // We first find the class loader of our caller. If it is the outer method, we can directly
+  // use its class loader. Otherwise, we also need to resolve our caller.
   StackHandleScope<2> hs(Thread::Current());
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
-  Handle<mirror::ClassLoader> class_loader(hs.NewHandle(outer_method->GetClassLoader()));
+  MutableHandle<mirror::ClassLoader> class_loader(hs.NewHandle<mirror::Class>(nullptr));
   Handle<mirror::DexCache> dex_cache(hs.NewHandle(outer_method->GetDexCache()));
+  if (inlining_depth == 0) {
+    class_loader.Assign(outer_method->GetClassLoader());
+  } else {
+    caller = GetResolvedMethod(outer_method, inline_info, inlining_depth - 1);
+    class_loader.Assign(caller->GetClassLoader());
+  }
+
   return class_linker->ResolveMethod(
       *outer_method->GetDexFile(), method_index, dex_cache, class_loader, nullptr, invoke_type);
 }
@@ -82,10 +94,7 @@ inline ArtMethod* GetCalleeSaveMethodCaller(ArtMethod** sp,
     DCHECK(stack_map.IsValid());
     if (stack_map.HasInlineInfo(encoding)) {
       InlineInfo inline_info = code_info.GetInlineInfoOf(stack_map, encoding);
-      uint32_t method_index = inline_info.GetMethodIndexAtDepth(inline_info.GetDepth() - 1);
-      InvokeType invoke_type = static_cast<InvokeType>(
-          inline_info.GetInvokeTypeAtDepth(inline_info.GetDepth() - 1));
-      caller = GetResolvedMethod(outer_method, method_index, invoke_type);
+      caller = GetResolvedMethod(outer_method, inline_info, inline_info.GetDepth() - 1);
     }
   }
 
diff --git a/runtime/stack.cc b/runtime/stack.cc
index 5aeca98a88..11c94dbbb8 100644
--- a/runtime/stack.cc
+++ b/runtime/stack.cc
@@ -126,10 +126,7 @@ ArtMethod* StackVisitor::GetMethod() const {
     if (IsInInlinedFrame()) {
       size_t depth_in_stack_map = current_inlining_depth_ - 1;
       InlineInfo inline_info = GetCurrentInlineInfo();
-      uint32_t method_index = inline_info.GetMethodIndexAtDepth(depth_in_stack_map);
-      InvokeType invoke_type =
-          static_cast<InvokeType>(inline_info.GetInvokeTypeAtDepth(depth_in_stack_map));
-      return GetResolvedMethod(*GetCurrentQuickFrame(), method_index, invoke_type);
+      return GetResolvedMethod(*GetCurrentQuickFrame(), inline_info, depth_in_stack_map);
     } else {
       return *cur_quick_frame_;
     }
diff --git a/test/497-inlining-and-class-loader/clear_dex_cache.cc b/test/497-inlining-and-class-loader/clear_dex_cache.cc
new file mode 100644
index 0000000000..f9b33a2874
--- /dev/null
+++ b/test/497-inlining-and-class-loader/clear_dex_cache.cc
@@ -0,0 +1,46 @@
+/*
+ * 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 "art_method-inl.h"
+#include "jni.h"
+#include "scoped_thread_state_change.h"
+#include "stack.h"
+#include "thread.h"
+
+namespace art {
+
+namespace {
+
+extern "C" JNIEXPORT jobject JNICALL Java_Main_cloneResolvedMethods(JNIEnv*, jclass, jclass cls) {
+  ScopedObjectAccess soa(Thread::Current());
+  return soa.Vm()->AddGlobalRef(
+      soa.Self(),
+      soa.Decode<mirror::Class*>(cls)->GetDexCache()->GetResolvedMethods()->Clone(soa.Self()));
+}
+
+extern "C" JNIEXPORT void JNICALL Java_Main_restoreResolvedMethods(
+    JNIEnv*, jclass, jclass cls, jobject old_cache) {
+  ScopedObjectAccess soa(Thread::Current());
+  mirror::PointerArray* now = soa.Decode<mirror::Class*>(cls)->GetDexCache()->GetResolvedMethods();
+  mirror::PointerArray* old = soa.Decode<mirror::PointerArray*>(old_cache);
+  for (size_t i = 0, e = old->GetLength(); i < e; ++i) {
+    now->SetElementPtrSize(i, old->GetElementPtrSize<void*>(i, sizeof(void*)), sizeof(void*));
+  }
+}
+
+}  // namespace
+
+}  // namespace art
diff --git a/test/497-inlining-and-class-loader/expected.txt b/test/497-inlining-and-class-loader/expected.txt
new file mode 100644
index 0000000000..18d2f2da12
--- /dev/null
+++ b/test/497-inlining-and-class-loader/expected.txt
@@ -0,0 +1,7 @@
+java.lang.Exception
+	at Main.$noinline$bar(Main.java:139)
+	at Level2.$inline$bar(Main.java:88)
+	at Level1.$inline$bar(Main.java:82)
+	at LoadedByMyClassLoader.bar(Main.java:94)
+	at java.lang.reflect.Method.invoke(Native Method)
+	at Main.main(Main.java:113)
diff --git a/test/497-inlining-and-class-loader/info.txt b/test/497-inlining-and-class-loader/info.txt
new file mode 100644
index 0000000000..e7f02aaf34
--- /dev/null
+++ b/test/497-inlining-and-class-loader/info.txt
@@ -0,0 +1,2 @@
+Regression test for optimizing to ensure it is using
+the correct class loader when walking inlined frames.
diff --git a/test/497-inlining-and-class-loader/src/Main.java b/test/497-inlining-and-class-loader/src/Main.java
new file mode 100644
index 0000000000..bb8da6d3a0
--- /dev/null
+++ b/test/497-inlining-and-class-loader/src/Main.java
@@ -0,0 +1,145 @@
+/*
+ * 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.
+ */
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.List;
+
+class MyClassLoader extends ClassLoader {
+  MyClassLoader() throws Exception {
+    super(MyClassLoader.class.getClassLoader());
+
+    // Some magic to get access to the pathList field of BaseDexClassLoader.
+    ClassLoader loader = getClass().getClassLoader();
+    Class<?> baseDexClassLoader = loader.getClass().getSuperclass();
+    Field f = baseDexClassLoader.getDeclaredField("pathList");
+    f.setAccessible(true);
+    Object pathList = f.get(loader);
+
+    // Some magic to get access to the dexField field of pathList.
+    f = pathList.getClass().getDeclaredField("dexElements");
+    f.setAccessible(true);
+    dexElements = (Object[]) f.get(pathList);
+    dexFileField = dexElements[0].getClass().getDeclaredField("dexFile");
+    dexFileField.setAccessible(true);
+  }
+
+  Object[] dexElements;
+  Field dexFileField;
+
+  static ClassLoader level1ClassLoader;
+
+  protected Class<?> loadClass(String className, boolean resolve) throws ClassNotFoundException {
+    if (this != level1ClassLoader) {
+      if (className.equals("Level1")) {
+        return level1ClassLoader.loadClass(className);
+      } else if (className.equals("Level2")) {
+        throw new ClassNotFoundException("None of my methods require Level2!");
+      } else if (!className.equals("LoadedByMyClassLoader")) {
+        // We're only going to handle LoadedByMyClassLoader.
+        return getParent().loadClass(className);
+      }
+    } else {
+      if (className != "Level1" && className != "Level2") {
+        return getParent().loadClass(className);
+      }
+    }
+
+    // Mimic what DexPathList.findClass is doing.
+    try {
+      for (Object element : dexElements) {
+        Object dex = dexFileField.get(element);
+        Method method = dex.getClass().getDeclaredMethod(
+            "loadClassBinaryName", String.class, ClassLoader.class, List.class);
+
+        if (dex != null) {
+          Class clazz = (Class)method.invoke(dex, className, this, null);
+          if (clazz != null) {
+            return clazz;
+          }
+        }
+      }
+    } catch (Exception e) { /* Ignore */ }
+    return null;
+  }
+}
+
+class Level1 {
+  public static void $inline$bar() {
+    Level2.$inline$bar();
+  }
+}
+
+class Level2 {
+  public static void $inline$bar() {
+    Main.$noinline$bar();
+  }
+}
+
+class LoadedByMyClassLoader {
+  public static void bar() {
+    Level1.$inline$bar();
+  }
+}
+
+class Main {
+  static {
+    System.loadLibrary("arttest");
+  }
+
+  public static void main(String[] args) throws Exception {
+    // Clone resolved methods, to restore the original version just
+    // before we walk the stack in $noinline$bar.
+    savedResolvedMethods = cloneResolvedMethods(Main.class);
+
+    MyClassLoader o = new MyClassLoader();
+    MyClassLoader.level1ClassLoader = new MyClassLoader();
+    Class foo = o.loadClass("LoadedByMyClassLoader");
+    Method m = foo.getDeclaredMethod("bar");
+    try {
+      m.invoke(null);
+    } catch (Error e) { /* Ignore */ }
+  }
+
+  public static void $inline$bar() {
+  }
+
+  public static void $noinline$bar() {
+    try {
+      // Be evil and clear all dex cache entries.
+      Field f = Class.class.getDeclaredField("dexCache");
+      f.setAccessible(true);
+      Object dexCache = f.get(Main.class);
+      f = dexCache.getClass().getDeclaredField("resolvedTypes");
+      f.setAccessible(true);
+      Object[] array = (Object[]) f.get(dexCache);
+      for (int i = 0; i < array.length; i++) {
+        array[i] = null;
+      }
+      restoreResolvedMethods(Main.class, savedResolvedMethods);
+    } catch (Throwable t) { /* Ignore */ }
+
+    // This will walk the stack, trying to resolve methods in it.
+    // Because we cleared dex cache entries, we will have to find
+    // classes again, which require to use the correct class loader
+    // in the presence of inlining.
+    new Exception().printStackTrace();
+  }
+  static Object savedResolvedMethods;
+
+  static native Object cloneResolvedMethods(Class<?> cls);
+  static native void restoreResolvedMethods(Class<?> cls, Object saved);
+}
diff --git a/test/Android.libarttest.mk b/test/Android.libarttest.mk
index 847ad0d2f7..fcb9f8a779 100644
--- a/test/Android.libarttest.mk
+++ b/test/Android.libarttest.mk
@@ -34,7 +34,8 @@ LIBARTTEST_COMMON_SRC_FILES := \
   455-set-vreg/set_vreg_jni.cc \
   457-regs/regs_jni.cc \
   461-get-reference-vreg/get_reference_vreg_jni.cc \
-  466-get-live-vreg/get_live_vreg_jni.cc
+  466-get-live-vreg/get_live_vreg_jni.cc \
+  497-inlining-and-class-loader/clear_dex_cache.cc
 
 ART_TARGET_LIBARTTEST_$(ART_PHONY_TEST_TARGET_SUFFIX) += $(ART_TARGET_TEST_OUT)/$(TARGET_ARCH)/libarttest.so
 ifdef TARGET_2ND_ARCH
diff --git a/test/Android.run-test.mk b/test/Android.run-test.mk
index 82a62953d5..469df1f2b6 100644
--- a/test/Android.run-test.mk
+++ b/test/Android.run-test.mk
@@ -338,6 +338,7 @@ TEST_ART_BROKEN_NDEBUG_TESTS := \
   457-regs \
   461-get-reference-vreg \
   466-get-live-vreg \
+  497-inlining-and-class-loader \
 
 ifneq (,$(filter ndebug,$(RUN_TYPES)))
   ART_TEST_KNOWN_BROKEN += $(call all-run-test-names,$(TARGET_TYPES),ndebug,$(PREBUILD_TYPES), \