> -----Original Message----- > From: Eric Botcazou [mailto:ebotca...@adacore.com] > Sent: 27 November 2013 18:27 > To: Paulo Matos > Cc: gcc@gcc.gnu.org > Subject: Re: reg_nonzero_bits_for_combine misunderstood > > > But the problem is that if the mode of the register is larger than the mode > > of the register when last set then we can't know anything about > > nonzero_bits. > > Right, this case is handled for nonzero_sign_valid a few lines below. > > > Fixed the problem. Any comments? > > Why not duplicate the treatment applied for nonzero_sign_valid? >
Right, didn't notice nonzero_sign_valid below. I think restricting mode == last_set_mode is too restrictive. nonzero_bits is still valid if the new mode has less precision than the old mode. -- Paulo Matos
