Michael Collison <colli...@rivosinc.com> writes: > While working on autovectorizing for the RISCV port I encountered an issue > where can_duplicate_and_interleave_p assumes that GET_MODE_NUNITS is a > evenly divisible by two. The RISC-V target has vector modes (e.g. VNx1DImode), > where GET_MODE_NUNITS is equal to one. > > Tested on RISCV and x86_64-linux-gnu. Okay? > > 2023-03-09 Michael Collison <colli...@rivosinc.com> > > * tree-vect-slp.cc (can_duplicate_and_interleave_p): > Check that GET_MODE_NUNITS is greater than one. > --- > gcc/tree-vect-slp.cc | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc > index 9a4e000925e..add58113fa8 100644 > --- a/gcc/tree-vect-slp.cc > +++ b/gcc/tree-vect-slp.cc > @@ -426,7 +426,8 @@ can_duplicate_and_interleave_p (vec_info *vinfo, unsigned > int count, > if (vector_type > && VECTOR_MODE_P (TYPE_MODE (vector_type)) > && known_eq (GET_MODE_SIZE (TYPE_MODE (vector_type)), > - GET_MODE_SIZE (base_vector_mode))) > + GET_MODE_SIZE (base_vector_mode)) > + && known_gt (GET_MODE_NUNITS (TYPE_MODE (vector_type)), 1)) > { > /* Try fusing consecutive sequences of COUNT / NVECTORS elements > together into elements of type INT_TYPE and using the result
FWIW, I think it'd better to remove: poly_int64 half_nelts = exact_div (nelts, 2); declare: poly_uint64 half_nelts; before the if condition, and use: && multiple_p (GET_MODE_NUNITS (TYPE_MODE (vector_type)), 2, &half_nelts) instead of the known_gt. In other words, now that we can't assert the exact_div, we should check it (using multiple_p) instead. Thanks, Richard