[Bug target/102107] protocol register (r12) corrupted before a tail call

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102107

--- Comment #13 from Segher Boessenkool <segher at gcc dot gnu.org> ---
  /* If we need to save CR, put it into r12 or r11.  Choose r12 except when
     r12 will be needed by out-of-line gpr save.  */
  cr_save_regno = ((DEFAULT_ABI == ABI_AIX || DEFAULT_ABI == ABI_ELFv2)
                   && !(strategy & (SAVE_INLINE_GPRS
                                    | SAVE_NOINLINE_GPRS_SAVES_LR))
                   ? 11 : 12);