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| author | Richard Guenther <rguenther@suse.de> | 2006-05-15 17:35:48 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2006-05-15 17:35:48 +0000 |
| commit | 7136db7ac5b31e9b7ade5a740bb7201bbf0faebd (patch) | |
| tree | 346efb9b7010a61806bedde644eb95404dec240d /gcc/tree-ssa-loop-niter.c | |
| parent | b6398823e7ff715272f35ceae58da3d3219523cc (diff) | |
| download | gcc-7136db7ac5b31e9b7ade5a740bb7201bbf0faebd.zip gcc-7136db7ac5b31e9b7ade5a740bb7201bbf0faebd.tar.gz gcc-7136db7ac5b31e9b7ade5a740bb7201bbf0faebd.tar.bz2 | |
re PR tree-optimization/27603 (wrong code, apparently due to bad VRP (-O2))
2006-05-15 Richard Guenther <rguenther@suse.de>
PR tree-optimization/27603
* tree-ssa-loop-niter.c (infer_loop_bounds_from_undefined):
Do computations in original type.
* gcc.dg/torture/pr27603.c: New testcase.
From-SVN: r113797
Diffstat (limited to 'gcc/tree-ssa-loop-niter.c')
| -rw-r--r-- | gcc/tree-ssa-loop-niter.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c index a3c5791..4dd05ea 100644 --- a/gcc/tree-ssa-loop-niter.c +++ b/gcc/tree-ssa-loop-niter.c @@ -1587,7 +1587,6 @@ infer_loop_bounds_from_undefined (struct loop *loop) tree scev = instantiate_parameters (loop, analyze_scalar_evolution (loop, op0)); tree type = chrec_type (scev); - tree utype; if (chrec_contains_undetermined (scev) || TYPE_UNSIGNED (type)) @@ -1604,20 +1603,23 @@ infer_loop_bounds_from_undefined (struct loop *loop) || TYPE_MAX_VALUE (type) == NULL_TREE) break; - utype = unsigned_type_for (type); - if (tree_int_cst_lt (step, integer_zero_node)) - diff = fold_build2 (MINUS_EXPR, utype, init, - TYPE_MIN_VALUE (type)); - else - diff = fold_build2 (MINUS_EXPR, utype, - TYPE_MAX_VALUE (type), init); - - if (!integer_zerop (step)) + if (integer_nonzerop (step)) { - estimation = fold_build2 (CEIL_DIV_EXPR, utype, diff, + tree utype; + + if (tree_int_cst_lt (step, integer_zero_node)) + diff = fold_build2 (MINUS_EXPR, type, init, + TYPE_MIN_VALUE (type)); + else + diff = fold_build2 (MINUS_EXPR, type, + TYPE_MAX_VALUE (type), init); + + utype = unsigned_type_for (type); + estimation = fold_build2 (CEIL_DIV_EXPR, type, diff, step); - record_estimate (loop, estimation, boolean_true_node, - stmt); + record_estimate (loop, + fold_convert (utype, estimation), + boolean_true_node, stmt); } } |