[Bug target/70814] atomic store of __int128 is not lock free on aarch64

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70814

--- Comment #5 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
I don't think so.  It's to do with whether the CPU is permitted to 'crack' the
operation into multiple micro-ops that proceed independently down the pipeline.
 LDAXP could still be cracked in this way provided that from that CPU's
perspective other memory operations from that core were not re-ordered with
respect to that operation in an incompatible manner.  However, external memory
operations could still cause the separate micro-ops to see different values.