https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115517
--- Comment #2 from Hongtao Liu <liuhongt at gcc dot gnu.org> --- (In reply to Richard Biener from comment #1) > Btw, I had opened PR115490 with my results for this already. Some mitigation > should be from optimizing ISEL expansion to vcond_mask and I'd start with > looking at some of the fallout from that side (note that might require > the backend reject not natively implemented vec_cmp via its operand 1 > predicate) w/o AVX512, vector integer comparison only supports EQ/GT, others comparison rtx_cost is transformed to that. (.i.e GTU is emulated with us_minus + eq + negative the vector mask) If we restrict the predicate of operand 1, would middle-end reject vectorization (or lower it to scalar version)?
