https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106574
--- Comment #7 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- I'd suggest looking at the generated assembly. I don't know exactly what you mean by "putting a math_opt_barrier on this line"; it would need to be used in a way that ensures a dependency for all the code after SET_RESTORE_ROUNDL (for example, "xx = math_opt_barrier (xx);").
