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

[Rickard Bäckman]

Looks good.

/R

On 03/23, Patric Hedlin wrote:
> Hi,
> 
> Please review this minor change/fix:
> 
>     https://bugs.openjdk.java.net/browse/JDK-8011352
> 
> Rationale:
> 
>     Replacing assumption on '_younger_window' being available when
> performing lookup on OUT-register part (in window), in order to
> handle such access in the same manner as other "out-of-scope" lookup
> (i.e. by returning NULL).
> 
> Regards,
> Patric
> 
> 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");
>