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| author | Richard Biener <rguenther@suse.de> | 2015-02-18 09:48:57 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2015-02-18 09:48:57 +0000 |
| commit | 6f423f4c894fe9dada8ad862b237001c99aa6150 (patch) | |
| tree | 2c4fcab7f1604b9e1c836636fcbeee0400944e23 /gcc/tree-ssa-dom.c | |
| parent | c7400e2fecfd0cc44c553517a59f8a70951cf6cf (diff) | |
| download | gcc-6f423f4c894fe9dada8ad862b237001c99aa6150.zip gcc-6f423f4c894fe9dada8ad862b237001c99aa6150.tar.gz gcc-6f423f4c894fe9dada8ad862b237001c99aa6150.tar.bz2 | |
re PR tree-optimization/62217 (DOM confuses complete unrolling which in turn causes VRP to warn)
2015-02-18 Richard Biener <rguenther@suse.de>
PR tree-optimization/62217
* tree-ssa-dom.c (cprop_operand): Avoid propagating copies
into BIVs.
* gcc.dg/tree-ssa/cunroll-11.c: New testcase.
From-SVN: r220785
Diffstat (limited to 'gcc/tree-ssa-dom.c')
| -rw-r--r-- | gcc/tree-ssa-dom.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index 9f0b2a5..096e471 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -2291,11 +2291,16 @@ cprop_operand (gimple stmt, use_operand_p op_p) if (!may_propagate_copy (op, val)) return; - /* Do not propagate copies into simple IV increment statements. - See PR23821 for how this can disturb IV analysis. */ - if (TREE_CODE (val) != INTEGER_CST - && simple_iv_increment_p (stmt)) - return; + /* Do not propagate copies into BIVs. + See PR23821 and PR62217 for how this can disturb IV and + number of iteration analysis. */ + if (TREE_CODE (val) != INTEGER_CST) + { + gimple def = SSA_NAME_DEF_STMT (op); + if (gimple_code (def) == GIMPLE_PHI + && gimple_bb (def)->loop_father->header == gimple_bb (def)) + return; + } /* Dump details. */ if (dump_file && (dump_flags & TDF_DETAILS)) |