Hi Segher, > > > To implement this, and some closely related transformations, we > > > build upon the existing val_signbit_known_clear_p predicate. In the > > > first chunk, nonzero_bits knows that FFS and ABS can't leave the > > > sign-bit bit set, > > > > Is that guaranteed in all cases? Also at -O0, also for args bigger > > than 64 bits? > > val_signbit_known_clear_p should work for any size/precision arg.
No, you're right! Please forgive/excuse me. Neither val_signbit_p nor nonzero_bits have yet been updated to use "wide_int", so don't work for TImode or wider modes. Doh! I'm shocked. Roger --
