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| author | Richard Biener <rguenther@suse.de> | 2018-08-29 06:47:14 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2018-08-29 06:47:14 +0000 |
| commit | e37f7da9c4b77aac0690c190206b286b9c82becd (patch) | |
| tree | 208e7818f50e91587a3afe639d1449e2bde8a351 /gcc/tree-ssa-sccvn.c | |
| parent | efc601240c12628df7ec467ac07a322306f80b71 (diff) | |
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re PR tree-optimization/87126 (ICE on valid code at -Os and above on x86_64-linux-gnu: in vn_reference_insert, at tree-ssa-sccvn.c:2698)
2018-08-29 Richard Biener <rguenther@suse.de>
PR tree-optimization/87126
* tree-ssa-sccvn.c (vn_reference_insert): Remove assert.
* gcc.dg/tree-ssa/pr87126.c: New testcase.
From-SVN: r263944
Diffstat (limited to 'gcc/tree-ssa-sccvn.c')
| -rw-r--r-- | gcc/tree-ssa-sccvn.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index 2556b0c..aaac430 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -2696,7 +2696,17 @@ vn_reference_insert (tree op, tree result, tree vuse, tree vdef) but save a lookup if we deal with already inserted refs here. */ if (*slot) { - gcc_assert (operand_equal_p ((*slot)->result, vr1->result, 0)); + /* We cannot assert that we have the same value either because + when disentangling an irreducible region we may end up visiting + a use before the corresponding def. That's a missed optimization + only though. See gcc.dg/tree-ssa/pr87126.c for example. */ + if (dump_file && (dump_flags & TDF_DETAILS) + && !operand_equal_p ((*slot)->result, vr1->result, 0)) + { + fprintf (dump_file, "Keeping old value "); + print_generic_expr (dump_file, (*slot)->result); + fprintf (dump_file, " because of collision\n"); + } free_reference (vr1); obstack_free (&vn_tables_obstack, vr1); return; |