diff options
Diffstat (limited to 'gcc/tree-ssa-pre.c')
| -rw-r--r-- | gcc/tree-ssa-pre.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index f165a1e..c3d2bba 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -2154,6 +2154,35 @@ compute_antic_aux (basic_block block, bool block_has_abnormal_pred_edge) /* clean (ANTIC_IN (block)) is defered to after the iteration converged because it can cause non-convergence, see for example PR81181. */ + /* Intersect ANTIC_IN with the old ANTIC_IN. This is required until + we properly represent the maximum expression set, thus not prune + values without expressions during the iteration. */ + if (was_visited + && bitmap_and_into (&ANTIC_IN (block)->values, &old->values)) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "warning: intersecting with old ANTIC_IN " + "shrinks the set\n"); + /* Prune expressions not in the value set. */ + bitmap_iterator bi; + unsigned int i; + unsigned int to_clear = -1U; + FOR_EACH_EXPR_ID_IN_SET (ANTIC_IN (block), i, bi) + { + if (to_clear != -1U) + { + bitmap_clear_bit (&ANTIC_IN (block)->expressions, to_clear); + to_clear = -1U; + } + pre_expr expr = expression_for_id (i); + unsigned int value_id = get_expr_value_id (expr); + if (!bitmap_bit_p (&ANTIC_IN (block)->values, value_id)) + to_clear = i; + } + if (to_clear != -1U) + bitmap_clear_bit (&ANTIC_IN (block)->expressions, to_clear); + } + if (!bitmap_set_equal (old, ANTIC_IN (block))) { changed = true; |