https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60969
--- Comment #17 from H.J. Lu <hjl.tools at gmail dot com> --- As long as both MMX and X87 registers are available to register allocator, they may be used at the same time even if MMX usage is disparaged. Can we disable MMX registers when x87 registers used on a per-function basis?
