[13] RFR (S): 8223171: Redundant nmethod dependencies for effectively final methods

[dean.long at oracle.com]

Can you also add check_unique_method(ctxk, uniqm) to the version of 
assert_unique_concrete_method that takes a Method*?
Otherwise, the changes look good to me.

dl

On 5/1/19 9:52 AM, Vladimir Ivanov wrote:
>
>> Does this allow us to assert !uniqm->can_be_statically_bound() in 
>> Dependencies::assert_unique_concrete_method?
>
> In general, no. It doesn't hold for final methods: dependency is still 
> needed when context is broad enough, since an overriding method can be 
> loaded in a different part of the hierarchy (under the same context 
> class).
>
> In case of the adjusted checks it's safe, since context == method 
> holder when actual_receiver->is_final() == true.
>
>    if (!callee->is_final_method() && !callee->is_private() && 
> !actual_receiver->is_final()) {
> dependencies()->assert_unique_concrete_method(actual_receiver, 
> cha_monomorphic_target);
>     }
>
> I refactored the patch a bit:
>   http://cr.openjdk.java.net/~vlivanov/8223171/webrev.01/
>
>>> Moreover, C2 does add dependencies for private methods.
>
> I take it back. Earlier checks handle private methods. Only methods on 
> final classes get redundant dependencies.
>
> Best regards,
> Vladimir Ivanov