From 7cc2824e39440dd71a9d2832c51ef260bb36d8ca Mon Sep 17 00:00:00 2001 From: Andrew MacLeod Date: Mon, 31 Oct 2022 09:53:01 -0400 Subject: [PATCH 1/3] Intersect with nonzero bits can indicate change incorrectly. * value-range.cc (irange::intersect_nonzero_bits): If new non-zero mask is the same as original, flag no change. --- gcc/value-range.cc | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/gcc/value-range.cc b/gcc/value-range.cc index 03b3c4b4a65..3743ec714b3 100644 --- a/gcc/value-range.cc +++ b/gcc/value-range.cc @@ -3017,6 +3017,10 @@ irange::intersect_nonzero_bits (const irange &r) if (mask_to_wi (m_nonzero_mask, t) != mask_to_wi (r.m_nonzero_mask, t)) { wide_int nz = get_nonzero_bits () & r.get_nonzero_bits (); + // If the nonzero bits did not change, return false. + if (nz == get_nonzero_bits ()) + return false; + m_nonzero_mask = wide_int_to_tree (t, nz); if (set_range_from_nonzero_bits ()) return true; -- 2.37.3