[Bug target/79964] Cortex A53 codegen still not optimal

[tulipawn at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79964

--- Comment #2 from PeteVine <tulipawn at gmail dot com> ---
I can confirm the first part of the issue gets fixed with this patch:

https://gcc.gnu.org/ml/gcc-patches/2017-04/msg01415.html

but there's a regression in gcc8 concerning the second part. (or rather the
workarounds don't work any more) 

http://openbenchmarking.org/result/1704298-RI-CRAYREGRE13

("basic flags" didn't deactivate -mfix-cortex-a53-843419, hence the difference)