JDK10/RFR(XXS): 8011352: C1: TraceCodeBlobStacks crashes fastdebug solaris sparc

[Roland Westrelin]

> Patch below:
>
> -----8<-----
>
> --- old/src/cpu/sparc/vm/frame_sparc.cpp	Wed Mar 22 16:47:13 2017
> +++ new/src/cpu/sparc/vm/frame_sparc.cpp	Wed Mar 22 16:47:12 2017
> @@ -123,8 +123,8 @@
>       reg = regname->as_Register();
>     }
>     if (reg->is_out()) {
> -    assert(_younger_window != NULL, "Younger window should be available");
> -    return second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];
> +    return _younger_window == NULL ? NULL :
> +      second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];
>     }
>     if (reg->is_local() || reg->is_in()) {
>       assert(_window != NULL, "Window should be available");

That looks reasonable to me.

Roland.