[10] RFR: 8186915 - AARCH64: Intrinsify squareToLen and mulAdd

[Dmitrij Pochepko]

Hi,

Andrew, do you believe this is ok to push?

Thanks,

Dmitrij


....

On 06.09.2017 20:39, Dmitrij wrote:
>
> I've compared it by calling square and multiply methods and got 
> following results(ThunderX):
>
>
> Benchmark                                        (size, ints) Mode 
> Cnt      Score     Error  Units
> BigIntegerBench.implMutliplyToLenReflect       1  avgt    5 186.930 ?  
> 14.933  ns/op  (26% slower)
> BigIntegerBench.implMutliplyToLenReflect       2  avgt    5 194.095 ?  
> 11.857  ns/op  (12% slower)
> BigIntegerBench.implMutliplyToLenReflect       3  avgt    5 233.912 
> ?   4.229  ns/op   (24% slower)
> BigIntegerBench.implMutliplyToLenReflect       5  avgt    5 308.349 ?  
> 20.383  ns/op  (22% slower)
> BigIntegerBench.implMutliplyToLenReflect      10  avgt    5 475.839 
> ?   6.232  ns/op  (same)
> BigIntegerBench.implMutliplyToLenReflect      50  avgt    5 6514.691 
> ?  76.934  ns/op (same)
> BigIntegerBench.implMutliplyToLenReflect      90  avgt    5 20347.040 
> ? 224.290  ns/op (3% slower)
> BigIntegerBench.implMutliplyToLenReflect     127  avgt    5 41929.302 
> ? 181.053  ns/op (9% slower)
>
> BigIntegerBench.implSquareToLenReflect         1  avgt    5 147.751 ?  
> 12.760  ns/op
> BigIntegerBench.implSquareToLenReflect         2  avgt    5 173.804 
> ?   4.850  ns/op
> BigIntegerBench.implSquareToLenReflect         3  avgt    5 187.822 ?  
> 34.027  ns/op
> BigIntegerBench.implSquareToLenReflect         5  avgt    5 251.995 ?  
> 19.711  ns/op
> BigIntegerBench.implSquareToLenReflect        10  avgt    5 474.489 
> ?   1.040  ns/op
> BigIntegerBench.implSquareToLenReflect        50  avgt    5 6493.768 
> ?  33.809  ns/op
> BigIntegerBench.implSquareToLenReflect        90  avgt    5 19766.524 
> ?  88.398  ns/op
> BigIntegerBench.implSquareToLenReflect       127  avgt    5 38448.202 
> ? 180.095  ns/op
>
>
> As we can see, squareToLen is faster than multiplyToLen.
>
> (I've updated benchmark code at 
> http://cr.openjdk.java.net/~dpochepk/8186915/BigIntegerBench.java)
>
> Thanks,
> Dmitrij