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| author | Richard Biener <rguenther@suse.de> | 2018-03-14 08:07:45 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2018-03-14 08:07:45 +0000 |
| commit | ec64ffc8501c20efdebefb494f3c90ab44199b60 (patch) | |
| tree | 579ef57ef3cf179c52ec685a1460b1bab0a52192 /gcc/tree-ssa-pre.c | |
| parent | 8fef0dc6a9479bdd4f82e52f7b7e1e678a817b75 (diff) | |
| download | gcc-ec64ffc8501c20efdebefb494f3c90ab44199b60.zip gcc-ec64ffc8501c20efdebefb494f3c90ab44199b60.tar.gz gcc-ec64ffc8501c20efdebefb494f3c90ab44199b60.tar.bz2 | |
re PR tree-optimization/84830 (ICE in compute_antic, at tree-ssa-pre.c:2388)
2018-03-14 Richard Biener <rguenther@suse.de>
PR tree-optimization/84830
* tree-ssa-pre.c (compute_antic_aux): Intersect the new ANTIC_IN
with the old one to avoid oscillations.
* gcc.dg/torture/pr84830.c: New testcase.
From-SVN: r258514
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; |