8069263: assert(fm == NULL || fm->method_holder() == _participants[n]) failed: sanity

Summary: default methods added to classes confuse dependency processing
Reviewed-by: kvn

src/share/vm/code/dependencies.cpp

@@ -811,7 +811,13 @@ class ClassHierarchyWalker {
     assert((uint)n <= (uint)_num_participants, "oob");
     Method* fm = _found_methods[n];
     assert(n == _num_participants || fm != NULL, "proper usage");
-    assert(fm == NULL || fm->method_holder() == _participants[n], "sanity");
+    if (fm != NULL && fm->method_holder() != _participants[n]) {
+      // Default methods from interfaces can be added to classes. In
+      // that case the holder of the method is not the class but the
+      // interface where it's defined.
+      assert(fm->is_default_method(), "sanity");
+      return NULL;
+    }
     return fm;
   }
 

test/compiler/inlining/DefaultMethodsDependencies.java

+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8069263
+ * @summary Deoptimization between array allocation and arraycopy may result in non initialized array
+ * @run main/othervm -XX:-BackgroundCompilation -XX:CompileOnly=DefaultMethodsDependencies::test -XX:CompileOnly=DefaultMethodsDependencies$I2::m1 DefaultMethodsDependencies
+ *
+ */
+
+public class DefaultMethodsDependencies {
+
+    interface I1 {
+        void m1();
+        // triggers processing of default methods in C1
+        default void m2() {
+        }
+    }
+
+    interface I2 extends I1 {
+        // added to C2 as default method
+        default void m1() {
+        }
+    }
+
+    static abstract class C1 implements I1 {
+    }
+
+    static class C2 extends C1 implements I2 {
+    }
+
+    static void test(C1 obj) {
+        obj.m1();
+    }
+
+    static public void main(String[] args) {
+        C2 obj = new C2();
+        for (int i = 0; i < 20000; i++) {
+            test(obj);
+        }
+    }
+}