[16] RFR[S]: 8251216: Implement MD5 intrinsics on AArch64

[Bernhard Urban-Forster]

Hey Doug,

replying on behalf for Ludovic, as he is on vacation :-)

Currently we are not planning to implement the intrinsic for Graal. Also we didn't check the generated code by Graal. I believe it will do a better job eliminated array bounds checks, but I'm curious to learn how "compiling the relevant Java code without array bounds checks" works. Is something like that done for other methods already?

This is the relevant Java method for the MD5 intrinsic:
https://github.com/openjdk/jdk/blob/733218137289d6a0eb705103ed7be30f1e68d17a/src/java.base/share/classes/sun/security/provider/MD5.java#L172


-Bernhard

________________________________________
From: Doug Simon <doug.simon at oracle.com>
Sent: Monday, August 10, 2020 11:55
To: Ludovic Henry
Cc: hotspot-compiler-dev at openjdk.java.net; aarch64-port-dev at openjdk.java.net; openjdk-aarch64
Subject: Re: [16] RFR[S]: 8251216: Implement MD5 intrinsics on AArch64

Hi Ludovic,

Are you considering also implementing this intrinsic in Graal?

Is the intrinsification purely about removing the array bounds checks? If so, it may be possible to have the Graal intrinsify the method by compiling the relevant Java code without array bounds checks.

-Doug

> On 9 Aug 2020, at 05:19, Ludovic Henry <luhenry at microsoft.com> wrote:
>
> Hello,
>
> Bug: https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.openjdk.java.net%2Fbrowse%2FJDK-8251216&data=02%7C01%7Cbeurba%40microsoft.com%7C087d5d80f9484f13ddcc08d83d138f3a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637326501506459034&sdata=C7Bi8BTsmtR3HFgWgYTw7jww63BcHGutNXE8o9x2bdY%3D&reserved=0
> Webrev: https://nam06.safelinks.protection.outlook.com/?url=http:%2F%2Fcr.openjdk.java.net%2F~luhenry%2F8251216%2Fwebrev.00&data=02%7C01%7Cbeurba%40microsoft.com%7C087d5d80f9484f13ddcc08d83d138f3a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637326501506459034&sdata=0CZOMfpmtPZiy64za8NYYpVjCdawmjGacEOc3WfADDA%3D&reserved=0
>
> Testing: Linux-AArch64, fastdebug, test/hotspot/jtreg/compiler/intrinsics/sha/ test/hotspot/jtreg:tier1 test/jdk:tier1
>
> This patch implements the MD5 intrinsic on AArch64 following its implementation on x86 [1]. The performance improvements are the following (on Linux-AArch64 on a Marvell TX2):
>
> -XX:-UseMD5Intrinsics
> Benchmark              (digesterName)  (length)  (provider)   Mode  Cnt     Score    Error   Units
> MessageDigests.digest             md5        64     DEFAULT  thrpt   10  1616.238 ± 28.082  ops/ms
> MessageDigests.digest             md5      1024     DEFAULT  thrpt   10   215.030 ±  0.691  ops/ms
> MessageDigests.digest             md5   1048576     DEFAULT  thrpt   10     0.228 ±  0.001  ops/ms
>
> -XX:+UseMD5Intrinsics
> Benchmark              (digesterName)  (length)  (provider)   Mode  Cnt     Score    Error   Units
> MessageDigests.digest             md5        64     DEFAULT  thrpt   10  2005.233 ± 40.513  ops/ms => 24% speedup
> MessageDigests.digest             md5      1024     DEFAULT  thrpt   10   275.979 ±  0.455  ops/ms => 28% speedup
> MessageDigests.digest             md5   1048576     DEFAULT  thrpt   10     0.279 ±  0.001  ops/ms => 22% speedup
>
> Thank you,
> Ludovic
>
> [1] https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.openjdk.java.net%2Fbrowse%2FJDK-8250902&data=02%7C01%7Cbeurba%40microsoft.com%7C087d5d80f9484f13ddcc08d83d138f3a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637326501506459034&sdata=5KcoG5n10rnVMU9y8L076jpCoEd0NBzNqr%2F8M5ghO3c%3D&reserved=0