Intrinsics for Math.min and max

[Martin Grajcar]

Done and attached. The results are pretty clear:

Benchmark                             Mode   Samples         Mean   Mean
error    Units
o.o.j.s.JmhMaxBenchmark.intrinsic     avgt       100        0.922
 0.001    ns/op
o.o.j.s.JmhMaxBenchmark.own           avgt       100        0.408
 0.005    ns/op

openjdk version "1.9.0-internal"
OpenJDK Runtime Environment (build
1.9.0-internal-maaartin_2014_02_18_06_05-b00)
OpenJDK 64-Bit Server VM (build 25.0-b62, mixed mode)
model name      : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz

Regards,
Martin.



On Tue, Apr 1, 2014 at 10:42 AM, Andrew Haley <aph at redhat.com> wrote:

> On 04/01/2014 07:02 AM, Martin Grajcar wrote:
> > I wonder if these intrinsics still make sense when the compiler can
> > generate movcc itself. According to this SO question
> >
> http://stackoverflow.com/questions/22752198/java-math-min-max-performance
> > it can lead to a factor two slowdown (I guess a JMH benchmark would
> confirm
> > this).
>
> Exactly.  Will you do it?
>
> Andrew.
>
>
>
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