https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107096
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to rsand...@gcc.gnu.org from comment #8) > (In reply to rguent...@suse.de from comment #7) > > more like precision but x86 uses QImode for two-element, four-element > > and eight-element masks (rather than two partial integer modes with > > two and four bits precision). > Ah, OK. So yeah, maybe the precision of the vector boolean element * > the number of elements. For SVE the following holds: diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index 1996ecfee7a..9b24b481867 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -10097,6 +10097,12 @@ vect_get_loop_mask (gimple_stmt_iterator *gsi, vec_loop_masks *masks, TYPE_VECTOR_SUBPARTS (vectype))); gimple_seq seq = NULL; mask_type = truth_type_for (vectype); + /* Assert that both mask types have the same total number of value + bits. */ + gcc_assert (known_eq (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (mask))) + * TYPE_VECTOR_SUBPARTS (TREE_TYPE (mask)), + TYPE_PRECISION (TREE_TYPE (mask_type)) + * TYPE_VECTOR_SUBPARTS (mask_type))); mask = gimple_build (&seq, VIEW_CONVERT_EXPR, mask_type, mask); if (seq) gsi_insert_seq_before (gsi, seq, GSI_SAME_STMT); for AVX the TYPE_PRECISION is always 1 so for unequal subparts we cannot directly share masks. I'm going to change LOOP_VINFO_MASKS from an array indexed by nV to a two-dimensional indexed by nV and bit-precision * subparts. Well, probably using a hash_map instead since this will be quite sparse. Or maybe not, but at least dynamically growing as we do now is difficult and subparts can be non-constant.