From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2136) id 4944238515DE; Tue, 15 Jun 2021 16:41:23 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4944238515DE MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Aldy Hernandez To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-1484] range-ops: (nonzero | X) is nonzero X-Act-Checkin: gcc X-Git-Author: Aldy Hernandez X-Git-Refname: refs/heads/master X-Git-Oldrev: 913b13fcb1dceea0e57a04cb77b11097b132cbf6 X-Git-Newrev: 4602714382f7a4603290b1ceb3121d9187debdb9 Message-Id: <20210615164123.4944238515DE@sourceware.org> Date: Tue, 15 Jun 2021 16:41:23 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Jun 2021 16:41:23 -0000 https://gcc.gnu.org/g:4602714382f7a4603290b1ceb3121d9187debdb9 commit r12-1484-g4602714382f7a4603290b1ceb3121d9187debdb9 Author: Aldy Hernandez Date: Mon Jun 14 12:51:48 2021 +0200 range-ops: (nonzero | X) is nonzero For bitwise or, nonzero|X is always nonzero. Make sure we don't drop to varying in this case. gcc/ChangeLog: * range-op.cc (operator_bitwise_or::wi_fold): Make sure nonzero|X is nonzero. (range_op_bitwise_and_tests): Add tests for above. Diff: --- gcc/range-op.cc | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/gcc/range-op.cc b/gcc/range-op.cc index 742e54686b4..e805f26a333 100644 --- a/gcc/range-op.cc +++ b/gcc/range-op.cc @@ -2534,11 +2534,20 @@ operator_bitwise_or::wi_fold (irange &r, tree type, new_lb = wi::max (new_lb, lh_lb, sign); if (wi::lt_p (rh_ub, 0, sign)) new_lb = wi::max (new_lb, rh_lb, sign); - // If the limits got swapped around, return varying. - if (wi::gt_p (new_lb, new_ub,sign)) - r.set_varying (type); - else - value_range_with_overflow (r, type, new_lb, new_ub); + // If the limits got swapped around, return a conservative range. + if (wi::gt_p (new_lb, new_ub, sign)) + { + // Make sure that nonzero|X is nonzero. + if (wi::gt_p (lh_lb, 0, sign) + || wi::gt_p (rh_lb, 0, sign) + || wi::lt_p (lh_ub, 0, sign) + || wi::lt_p (rh_ub, 0, sign)) + r.set_nonzero (type); + else + r.set_varying (type); + return; + } + value_range_with_overflow (r, type, new_lb, new_ub); } bool @@ -3744,6 +3753,18 @@ range_op_bitwise_and_tests () i1 = int_range<1> (integer_type_node); op_bitwise_and.op1_range (res, integer_type_node, i1, i2); ASSERT_TRUE (res == int_range<1> (integer_type_node)); + + // (NONZERO | X) is nonzero. + i1.set_nonzero (integer_type_node); + i2.set_varying (integer_type_node); + op_bitwise_or.fold_range (res, integer_type_node, i1, i2); + ASSERT_TRUE (res.nonzero_p ()); + + // (NEGATIVE | X) is nonzero. + i1 = int_range<1> (INT (-5), INT (-3)); + i2.set_varying (integer_type_node); + op_bitwise_or.fold_range (res, integer_type_node, i1, i2); + ASSERT_FALSE (res.contains_p (INT (0))); } void