https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64317
--- Comment #8 from Jeffrey A. Law <law at redhat dot com> --- And for GCC 5, ISTM the question that hasn't been answered, particularly with regard to the second reproducer is whether or this is a regression for the overall performance of that code. It's certainly possible that IRA determined that %ebx was better used to hold a different value and that the PIC register might end up in a call-clobbered register. If the object in %ebx is heavily used, the benefits of keeping that value in %ebx may outweigh the cost of having the PIC value in a different register (say perhaps one that is call-clobbered).
