https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89853
--- Comment #7 from Peter Bergner <bergner at gcc dot gnu.org> --- (In reply to Martin Jambor from comment #6) > Hi, the assembly of the most affected function does not change at all, just > its offset (is 0x10 bytes bigger). Aligning the loops in the function a bit > more avoids most of the slowdown but not quite all of it. In any event, > this is a microarchitectural problem that we probably cannot do anything > about. Sorry for the noise, I will check for this the next time before I > report a problem. We've seen similar issues on POWER, where a particular revision causes slight size changes in a function that changes the function offset of some other later function and that causes a performance change. Unfortunately, just increasing function alignment to eliminate that has other unintended performance issues. Thanks for isolating the issue.
