From a7d82b45edeed99a850595eee0e59d16c4df7aff Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 23 Nov 2023 09:49:59 +0100 Subject: [PATCH] tree-optimization/112344 - relax final value-replacement fix The following tries to reduce the number of cases we use an unsigned type for the addition when we know the original signed increment was OK which is when the total unsigned increment computed fits the signed type as well. This fixes the observed testsuite fallout. PR tree-optimization/112344 * tree-chrec.cc (chrec_apply): Only use an unsigned add when the overall increment doesn't fit the signed type. --- gcc/tree-chrec.cc | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/gcc/tree-chrec.cc b/gcc/tree-chrec.cc index f4ba130ba200..e2864e8d1310 100644 --- a/gcc/tree-chrec.cc +++ b/gcc/tree-chrec.cc @@ -646,9 +646,21 @@ chrec_apply (unsigned var, res = chrec_fold_multiply (utype, chrec_convert (utype, chrecr, NULL), res); - res = chrec_fold_plus (utype, - chrec_convert (utype, chrecl, NULL), res); - res = chrec_convert (type, res, NULL); + /* When the resulting increment fits the original type + do the increment in it. */ + if (TREE_CODE (res) == INTEGER_CST + && int_fits_type_p (res, TREE_TYPE (chrecr))) + { + res = chrec_convert (TREE_TYPE (chrecr), res, NULL); + res = chrec_fold_plus (type, chrecl, res); + } + else + { + res = chrec_fold_plus (utype, + chrec_convert (utype, chrecl, NULL), + res); + res = chrec_convert (type, res, NULL); + } } } else if (TREE_CODE (x) == INTEGER_CST -- 2.47.2