From 7136db7ac5b31e9b7ade5a740bb7201bbf0faebd Mon Sep 17 00:00:00 2001 From: Richard Guenther Date: Mon, 15 May 2006 17:35:48 +0000 Subject: re PR tree-optimization/27603 (wrong code, apparently due to bad VRP (-O2)) 2006-05-15 Richard Guenther 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 --- gcc/tree-ssa-loop-niter.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) (limited to 'gcc/tree-ssa-loop-niter.c') 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); } } -- cgit v1.1