RFR: 8266845: Shenandoah: Simplify SBS::load_reference_barrier implementation [v2]

[Aleksey Shipilev]

On Tue, 11 May 2021 12:22:09 GMT, Zhengyu Gu <zgu at openjdk.org> wrote:

>> Early return on null obj simplifies implementation and makes code more readable.
>> 
>> Test:
>> - [x] hotspot_gc_shenandoah
>
> Zhengyu Gu has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Aleksey's comments

Provisionally approving, modulo the nit.

src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.inline.hpp line 130:

> 128: 
> 129:   oop fwd = load_reference_barrier(obj);
> 130:   assert(fwd != nullptr, "Sanity");

`nullptr` -> `NULL` here too. Actually, why do we need this assert? I don't mind leaving it, if there is a reason.

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

Marked as reviewed by shade (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3956