https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79245
--- Comment #9 from James Greenhalgh <jgreenhalgh at gcc dot gnu.org> --- > I'm curious how that benchmarks for you (with -ftree-loop-distribution vs. > without). Taking trunk as 100%, I see a 2% gain on trunk with -fno-tree-loop-distribution-patterns , and 1% gain with your patch applied. I'm not sure where the other 1% is going. There are a few more examples of new memcpy calls in MAIN_ and inital_ , but they don't look hot so it may just be a second-order effect. Thanks for the fix.