[Bug target/93932] PowerPC vec_extract with variable element number has code regressions for V2DI/V2DF vectors

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93932

--- Comment #2 from Segher Boessenkool <segher at gcc dot gnu.org> ---
So the issue is that input_operand allows too much?

Other patterns that could use such a fix are float<QHI:mode><FP_ISA3:mode>2,
floatuns<QHI:mode><FP_ISA3:mode>2, movsd_store, movsd_load,
*vsx_le_permute_<mode>, vsx_set_v1ti, vsx_extract_<mode>_var,
vsx_extract_v4sf_var, vsx_extract_<mode>_var, 
*vsx_extract_<mode>_<VS_scalar>mode_var, vsx_splat_<mode>.
A few of those are probably safe, the define_expand ones for example; but
those are all uses of input_operand in an insn that isn't a movM (which
is the only place this predicate should be used).