RFR: Fix oop comparisons

[Roman Kennke]

Am Freitag, den 28.10.2016, 22:38 +0200 schrieb Aleksey Shipilev:
> On 10/28/2016 10:30 PM, Roman Kennke wrote:
> > 
> > While debugging, I found 2 little issues. In JVM_StopThread we need
> > to
> > add an == barrier for comparing thread objects, and in
> > stackwalk.cpp we
> > have a redundant comparison.
> > 
> > http://cr.openjdk.java.net/~rkennke/fixoopcomp/webrev.00/
> 
> Looks OK. Can go straight into upstream?

Nope. Because oopDesc::unsafe:equals() is introduced by us.

Roman