https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115494
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Andrew Pinski from comment #4) > Hmm. disabling: > > /* x | C -> C if we know that x & ~C == 0. */ > (simplify > (bit_ior SSA_NAME@0 INTEGER_CST@1) > (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) > && wi::bit_and_not (get_nonzero_bits (@0), wi::to_wide (@1)) == 0) > @1)) > > Fixes it. > > So this was caused/exposed by r14-3485-g6df8dcec7196e4 . > > Note that above pattern is hitting during PRE. I have to double check to > make sure that is correct. The match pattern is correct what we get through PRE is: _17 | 1 Where _17's range is [0,1] so obvious this is just 1. So either what pre is sending off to match-and-simplify is wrong or the way pre uses match-and-simplify is wrong. What the match does is correct for what it is given..
