https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123271
--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Up to you, I think right now the {add,sub,mul}v<mode>3 and negv<mode>2 patterns
are only used on targets with conditional traps, all other targets just defer
to libgcc (i.e. call __subvsi3 etc.). Though, if the sub insn with setting
flags and conditional jump and trap elsewhere together are smaller or equal to
calling that function + preparing the arguments for it, perhaps it might be a
good idea to do it like that.
I'd just recommend to do it in two steps, one which just renames the one named
pattern (so that you can easily backport it) and another one which introduces
whatever you decide to use.
