Mitigation of performance loss for Intel CPUs due JCC Erratum changes in microcode

[Erik Österlund]

Hi Andriy,

> On 17 Feb 2020, at 18:55, Andriy Plokhotnyuk <plokhotnyuk at gmail.com> wrote:
> 
> My question is: would be the HotSpot Dev team interested in mitigation of
> the issue in the Hotspot C2 compiler?
> 
> I found a bug report for the issue, but it is scoped for ZGC only:
> https://bugs.openjdk.java.net/browse/JDK-8234160

I made the fix general enough for basic C2 IR as well, with good results. Waiting for reviews ATM. Maybe I should remove ”ZGC” from the bug name...

Thanks,
/Erik