[Bug target/121498] long branches requires ra register but not modeled; causes issues sometimes with shrink wrapping and/or leaf functions

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121498

--- Comment #7 from Jeffrey A. Law <law at gcc dot gnu.org> ---
Note that GCC considers RA a fixed register because of its hidden uses.  RA is
not available to the regsiter allocator.  There is special code to save/restore
RA if the function is not a leaf function OR if the function is large enough to
potentially need long branch/call sequences.

If RA is not being saved in a function that has long branches/calls, then
that's a bug and I'd love to have a compilable testcase to investigate why.