RFR(XS): 8209684: Intrinsics that assume some input non null should use GraphKit::must_be_not_null()

[Tobias Hartmann]

Hi Roland,

looks good to me (I think you can remove the double new line at 5813).

Best regards,
Tobias

On 20.08.2018 10:21, Roland Westrelin wrote:
> 
> http://cr.openjdk.java.net/~roland/8209684/webrev.00/
> 
> A number of intrinsics omit null checks on inputs that are known to be
> not null. They should mark these inputs as not null instead with
> GraphKit::must_be_not_null().
> 
> This change is from the shenandoah repo where it's required:
> shenandoah's barrier read a field from the object. If the object is not
> registered to be not null then this field load can turn on some path
> into a load from a null object which causes C2 to crash.
> 
> Roland.
>