http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54114
--- Comment #4 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-08-07 20:28:05 UTC --- It seems quite clear to me that the new cost arises due to clobber_overlapping_mems, a relatively expensive operation that fixes a debug info correctness bug and that we just didn't do before. I'm afraid I can't think of a way to do it in a way that is significantly more efficient, so we'll have to choose between this additional cost, or living with debug locations that are no longer valid due to overlapping stores :-( I'm tempted to mark this as WONTFIX, but I thought I'd leave this open for a bit in case anyone else wants to give it a try.
