RFR (M) 8175368: [s390] Provide intrinsic implementation for CRC32C

[Schmidt, Lutz]

Thank you, Vladimir, for looking at this. 

Regards, Lutz


On 27.02.17, 22:30, "Vladimir Kozlov" <vladimir.kozlov at oracle.com> wrote:

    Shared changes are good. I assume s390 code will be reviewed by experts.
    
    Thanks,
    Vladimir
    
    On 2/27/17 9:34 AM, Schmidt, Lutz wrote:
    > Hi all,
    >
    >
    >
    > the webrev URL below was incorrect. It displayed the correct location,
    > but pointed elsewhere. The issue is fixed now and the URLs are correct.
    >
    >
    >
    > Thank you!
    >
    > Lutz
    >
    >
    >
    > *From: *Lutz Schmidt <lutz.schmidt at sap.com>
    > *Date: *Montag, 27. Februar 2017 um 15:55
    > *To: *"hotspot-compiler-dev at openjdk.java.net"
    > <hotspot-compiler-dev at openjdk.java.net>
    > *Subject: *RFR (M) 8175368: [s390] Provide intrinsic implementation for
    > CRC32C
    >
    >
    >
    > Hi all,
    >
    >
    >
    > may I kindly request reviews for my medium enhancement? Further down the
    > road, I would need a sponsor, too.
    >
    >
    >
    > Bug: https://bugs.openjdk.java.net/browse/JDK-8175368
    >
    > Webrev: http://cr.openjdk.java.net/~lucy/webrevs/8175368/
    >
    >
    >
    > Description:
    >
    > This intrinsic implementation provides some performance benefit over the
    > standard Java implementation. It uses only well-known “standard”
    > instructions, available on all supported IBM System z hardware. Being
    > very similar to the CRC32 intrinsics, it was tried to share as much code
    > as possible between these two.
    >
    >
    >
    > Performance may be expected to increase up to 2.0x, compared to a run
    > with –XX:-UseCRC32CIntrinsics. Actual speedup depends on the length of
    > the byte array fed into CRC32C and, to some extent, on the H/W
    > generation the test runs on.
    >
    >
    >
    > Thanks,
    >
    > Lutz
    >
    >
    >