RFR: 8259020: null-check of g1 write_ref_field_pre_entry is not necessary

[Xin Liu]

On Mon, 4 Jan 2021 23:58:13 GMT, Paul Hohensee <phh at openjdk.org> wrote:

>> orig is not null because G1BarrierSetC2 won't invoke write_ref_field_pre_entry 
>> if pre_val is NULL.
>
> Marked as reviewed by phh (Reviewer).

Thank you all reviewers and @phohensee for sponsoring it.

-------------

PR: https://git.openjdk.java.net/jdk/pull/1913