K 10
svn:author
V 8
jhibbits
K 8
svn:date
V 27
2019-11-15T04:33:07.196666Z
K 7
svn:log
V 376
atomic: Add atomic_cmpset_masked to powerpc and use it

Summary:
This is a more optimal way of doing atomic_compset_masked() than the
fallback in sys/_atomic_subword.h.  There's also an override for
_atomic_fcmpset_masked_word(), which may or may not be necessary, and is
unused for powerpc.

Reviewed by:	kevans, kib
Differential Revision:	https://reviews.freebsd.org/D22359

END