RFR: JDK-8221751: Shenandoah: Improve SATB enqueueing

[Andrew Haley]

On 4/2/19 4:07 PM, Roman Kennke wrote:
> http://cr.openjdk.java.net/~rkennke/JDK-8221751/webrev.02/
> 
> Testing: Passes hotspot_gc_shenandoah both x86 and aarch64
> 
> Ok?

  54       __ cmp(count, zr);
  55       __ br(Assembler::EQ, done);

should be

  cbz(count, done);

and this

  60       __ mov(rscratch2, ShenandoahHeap::MARKING);
  61       __ tst(rscratch1, rscratch2);
  62       __ br(Assembler::EQ, done);

should be

  62       __ tbz(rscratch1, ShenandoahHeap::MARKING_BITPOS, done);

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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