RFR: 8189107 - AARCH64: create intrinsic for pow

[Andrew Dinn]

Hello Dmitrij,

On 26/10/18 13:21, Dmitrij Pochepko wrote:
> I prepared new patch with all your comments addressed.

Excellent. Thank you very much for putting in all the required work.

> Changes:
> 
> - fixed huge y case
> 
> - updated scalbn block to use approach you suggested
> 
> - updated optimized algorithm pseudo code to reflect all changes, also
> fixed few minor pseudo code issues
> 
> - rearranged assembly code:
> 
> -- renamed registers variables to have names correlating to C-code where
> applicable
> 
> -- introduced local blocks with local labels and register mappings where
> applicable
> 
> -- removed unnecessary register remappings
> 
> -- moved odd/even check code generation to separate function
> 
> -- removed K_IS_0 and K_IS_1 branches code repetition
> 
> 
> - added simple jtreg test

Ok. I'll try to work through this as quick as possible but it may take a
day or two.

> I found that one of tests I was using (
> http://hg.openjdk.java.net/jdk/jdk/file/tip/test/jdk/java/lang/Math/PowTests.java)
> actually skip non-corner-case testing. Still, this test has very good
> set of input values, which can be re-used. I created enhancement for
> this test to actually test non-corner-case values (
> https://bugs.openjdk.java.net/browse/JDK-8211002 ). I modified this test
> locally to have everything testing and it passed.

I have already talked to Joe Darcy about PowTests.java and he explained
where this test came from and why it only covers the current set of
inputs. I am sure he will be happy to have it extended to cover extra
corner cases.

regards,


Andrew Dinn
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