https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69161
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2016-01-07
CC| |jakub at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
IMHO this is just invalid RTL.
@findex vec_duplicate
@item (vec_duplicate:@var{m} @var{x})
This operation converts a scalar into a vector or a small vector into a
larger one by duplicating the input values. The output vector mode must have
the same submodes as the input vector mode or the scalar modes, and the
number of output parts must be an integer multiple of the number of input
parts.
So, for (vec_duplicate:V4SI ()) the operand can be e.g SImode or V2SImode, but
not some CCmode or similar.
Thus, I'd expect you want:
(vec_duplicate:V4SI (eq:SI (reg:CC_NZ 66 cc)
(const_int 0 [0])))
Now, before combine the RTL is correct, but I think the bug is that e.g.
aarch64_cstore<mode> predicate uses aarch64_comparison_predicate predicate,
which is define_special_predicate and thus ignores mode.
On say if_then_else ignoring the mode is fine, but not when you have a SET,
which should have the same modes on SET_DEST and SET_SRC (unless the latter is
VOIDmode).
