[Bug target/63521] The AArch64 backend doesn't define REG_ALLOC_ORDER.

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63521

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
For future reference here are the 2 discussions about REG_ALLOC_ORDER for
aarch64
https://inbox.sourceware.org/gcc-patches/n998ucjwgk1....@arm.com/
https://inbox.sourceware.org/gcc-patches/mptjzxhperg....@arm.com/