[aarch64-port-dev ] RFR: 8129426: aarch64: add support for PopCount in C2

Andrew Dinn adinn at redhat.com
Mon Jun 22 14:34:05 UTC 2015

On 22/06/15 15:04, Andrew Haley wrote:
> On 06/22/2015 02:23 PM, Edward Nevill wrote:
>> Aarch64 currently does not support the PopCountI and PopCountL nodes in aarch64.ad
>> Please review and if OK I will push,
> Shouldn't mov in the IregI case be movw?  And iRegI be iRegIorL2I?

Agreed on both counts.

Strictly, for the PopCountI encoding /both/ mov operations -- i.e. to
and fro -- should be a movw (I assume that means passing enum tag T1F in
place of T1D?). However, using mov for the restore to $dst is safe as we
know the top 32 bits will be zero.

> I'm guessing that C2 won't do the MOVs itself if you specify the
> instruction as vRegD src.

I believe you guess right.


Andrew Dinn

More information about the hotspot-dev mailing list