RFR: unsafe oop comparison

[Aleksey Shipilev]

On 09/22/2017 04:43 PM, Zhengyu Gu wrote:
> Crash with -XX:+VerifyStrictOopOperations -XX:+PrintAssembly in debug build.
> 
> Webrev: http://cr.openjdk.java.net/~zgu/shenandoah/unsafe_eq/webrev.00/

Ouch, bad typo:

2384     if (oopDesc::unsafe_equals(0, (oop)Universe::non_oop_word())) {
                                   ^^^--- zero!

-Aleksey