https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110832
--- Comment #10 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Hongtao.liu from comment #9) > for mov<mode>_internal, we can just set alternative (v,v) with mode DI, then > it will use vmovq, for other alternatives which set sse_regs, the > instructions has already cleared the upper bits. Move instructions can be sanitized in ix86_expand_vector_move. If the target is in V2SFmode and the source is a subreg register, then movq_v2sf_to_sse should be emitted. However, we would still like to emit MOVAPS reg, reg for V2SF to V2SF moves, because MOVAPS may be eliminated by hardware, while MOVQ won't be.
