https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78509
--- Comment #12 from James Greenhalgh <jgreenhalgh at gcc dot gnu.org> --- I tried looking at the generated assembly for that test with the compilers I built before my patch series, and after the patch series + the fix above. I couldn't see any difference in code generated for the testcase you mention for each of the sets of options Jakub gave above (with -m3dnow, -O2, -m32 for the testcase). If this turns out to be my fault, I'll gladly look in to it - but I'll need help getting the x86 flags right again!