RFR(XS): 8223248: [AIX] Remove old xlC 10 workaround for load acquire

[Schmidt, Lutz]

Martin,
this change looks good to me. Please note: I'm not a reviewer!
You may want to think again if it is really necessary to keep the old comment. Your decision...
Thanks,
Lutz

On 02.05.19, 17:38, "hotspot-runtime-dev on behalf of Doerr, Martin" <hotspot-runtime-dev-bounces at openjdk.java.net on behalf of martin.doerr at sap.com> wrote:

    Hi,
    
    the load acquire implementation in orderAccess_aix_ppc.hpp still contains a workaround from the time in which we were using xlC 10.1:
    We use lwsync instead of twi+isync which is used on linux.
    This compiler is no longer supported and the VM has been tested with xlClang++ 16.1 (JDK13) without the workaround.
    (Already JDK8-12 require at least xlC 12.01. Also see https://wiki.openjdk.java.net/display/Build/Supported+Build+Platforms)
    
    I'd like AIX to use the same implementation as linux. Please review:
    http://cr.openjdk.java.net/~mdoerr/8223248_remove_XLC10_workaround/webrev.00/
    
    Best regards,
    Martin