*** old/src/share/vm/c1/c1_GraphBuilder.cpp	Tue Feb 14 20:36:20 2017
--- new/src/share/vm/c1/c1_GraphBuilder.cpp	Tue Feb 14 20:36:19 2017

*** 1915,1958 ****
--- 1915,1952 ----
      if ((code == Bytecodes::_invokevirtual && callee_holder->is_initialized()) ||
          (code == Bytecodes::_invokeinterface && callee_holder->is_initialized() && !actual_recv->is_interface())) {
        // Use CHA on the receiver to select a more precise method.
        cha_monomorphic_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv);
      } else if (code == Bytecodes::_invokeinterface && callee_holder->is_loaded() && receiver != NULL) {
        // if there is only one implementor of this interface then we
+       assert(callee_holder->is_interface(), "invokeinterface to non interface?");
+       // If there is only one implementor of this interface then we
        // may be able bind this invoke directly to the implementing
        // klass but we need both a dependence on the single interface
        // and on the method we bind to.  Additionally since all we know
        // about the receiver type is the it's supposed to implement the
        // interface we have to insert a check that it's the class we
        // expect.  Interface types are not checked by the verifier so
        // they are roughly equivalent to Object.
        ciInstanceKlass* singleton = NULL;
        if (target->holder()->nof_implementors() == 1) {
          singleton = target->holder()->implementor();
          assert(singleton != NULL && singleton != target->holder(),
                 "just checking");
  
          assert(holder->is_interface(), "invokeinterface to non interface?");
          ciInstanceKlass* decl_interface = (ciInstanceKlass*)holder;
          // the number of implementors for decl_interface is less or
+       // The number of implementors for declared_interface is less or
        // equal to the number of implementors for target->holder() so
        // if number of implementors of target->holder() == 1 then
        // number of implementors for decl_interface is 0 or 1. If
        // it's 0 then no class implements decl_interface and there's
        // no point in inlining.
          if (!holder->is_loaded() || decl_interface->nof_implementors() != 1 || decl_interface->has_nonstatic_concrete_methods()) {
!           singleton = NULL;
          }
        }
        if (singleton) {
!         cha_monomorphic_target = target->find_monomorphic_target(calling_klass, target->holder(), singleton);
+       ciInstanceKlass* singleton = NULL;
!       ciInstanceKlass* declared_interface = callee_holder;
+       if (declared_interface->nof_implementors() == 1 &&
+           (!target->is_default_method() || target->is_overpass()) /* CHA doesn't support default methods yet. */) {
+         singleton = declared_interface->implementor();
!         assert(singleton != NULL && singleton != declared_interface, "");
+         cha_monomorphic_target = target->find_monomorphic_target(calling_klass, declared_interface, singleton);
          if (cha_monomorphic_target != NULL) {
            // If CHA is able to bind this invoke then update the class
            // to match that class, otherwise klass will refer to the
            // interface.
            klass = cha_monomorphic_target->holder();
!           actual_recv = target->holder();
!           actual_recv = declared_interface;
  
            // insert a check it's really the expected class.
            CheckCast* c = new CheckCast(klass, receiver, copy_state_for_exception());
            c->set_incompatible_class_change_check();
            c->set_direct_compare(klass->is_final());

*** 1963,1979 ****
--- 1957,1967 ----
        }
      }
    }
  
    if (cha_monomorphic_target != NULL) {
      if (cha_monomorphic_target->is_abstract()) {
        // Do not optimize for abstract methods
        cha_monomorphic_target = NULL;
      }
    }
  
    if (cha_monomorphic_target != NULL) {
+     assert(!cha_monomorphic_target->is_abstract(), "");
      if (!(target->is_final_method())) {
        // If we inlined because CHA revealed only a single target method,
        // then we are dependent on that target method not getting overridden
        // by dynamic class loading.  Be sure to test the "static" receiver
        // dest_method here, as opposed to the actual receiver, which may