[Bug jit/66594] jitted code should use -mtune=native

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66594

--- Comment #2 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> This should be true on all targets which have -mcpu=native (or
> -march=native).  Note x86 options are not always the same on x86 vs arm vs
> aarch64 vs ppc.

Thanks.

Is there a way to express
  "give me the most specialized possible code for the current host"?
in a manner that's consistent across all supported hosts?
(e.g. in the "specs" language?)

e.g. "-march=native -mcpu=native -mtune=native"