This is a follow up report to bug 82989 The comment bug 82989, comment 12 details about the need for early decisions to be made about choosing to take either NEON code or ARM code. This means that at the expand phase, we should be able to make a clear choice and avoid mixing the two.
Confirmed.
GCC 9.1 has been released.
GCC 9.2 has been released.
GCC 9.3.0 has been released, adjusting target milestone.
GCC 9.4 is being released, retargeting bugs to GCC 9.5.
This was ultimately addressed by deciding not to use neon at all for 64-bit operations. Too many cases lead to very poor performance and with better optimization on the general regs expansions (which is only possible if a hard choice is made early) we generally end up with better code overall.