RFR(xs): 8211387: [Zero] atomic_copy64: Use ldrexd for atomic reads on ARMv7

[Andrew Haley]

On 10/06/2018 10:52 PM, David Holmes wrote:
> Bottom line seems to be:
> - clrex is not essential
> - clrex is probably not harmful to performance
> - clrex may benefit performance

clrex may also make performance worse: it's another instruction, after all.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671