diff options
Diffstat (limited to 'gcc/tree-vect-loop.c')
| -rw-r--r-- | gcc/tree-vect-loop.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c index 83fb848..005fa30 100644 --- a/gcc/tree-vect-loop.c +++ b/gcc/tree-vect-loop.c @@ -3291,6 +3291,32 @@ vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo, si->kind, si->stmt_info, si->misalign, vect_epilogue); } + + /* Calculate how many masks we need to generate. */ + unsigned int num_masks = 0; + rgroup_masks *rgm; + unsigned int num_vectors_m1; + FOR_EACH_VEC_ELT (LOOP_VINFO_MASKS (loop_vinfo), num_vectors_m1, rgm) + if (rgm->mask_type) + num_masks += num_vectors_m1 + 1; + gcc_assert (num_masks > 0); + + /* In the worst case, we need to generate each mask in the prologue + and in the loop body. One of the loop body mask instructions + replaces the comparison in the scalar loop, and since we don't + count the scalar comparison against the scalar body, we shouldn't + count that vector instruction against the vector body either. + + Sometimes we can use unpacks instead of generating prologue + masks and sometimes the prologue mask will fold to a constant, + so the actual prologue cost might be smaller. However, it's + simpler and safer to use the worst-case cost; if this ends up + being the tie-breaker between vectorizing or not, then it's + probably better not to vectorize. */ + (void) add_stmt_cost (target_cost_data, num_masks, vector_stmt, + NULL, 0, vect_prologue); + (void) add_stmt_cost (target_cost_data, num_masks - 1, vector_stmt, + NULL, 0, vect_body); } else if (npeel < 0) { |