[Bug tree-optimization/107009] [13 Regression] massive unnecessary code blowup in vectorizer

rguenth at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Fri Sep 23 06:43:53 GMT 2022


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107009

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
           Priority|P3                          |P1
                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
  # RANGE [irange] size_t [1, +INF]
  size_t n_12(D) = n;

the nonzero bits info on 'n' is gone.  DOM2 used to produce that and
CCP3 elides the __builtin_unreachable () but if DOM2 is disabled that
doesn't produce the nonzero bits.

DOM2 from trunk no longer sets nonzero bits.  CCP doesn't do any
conditional non-zero bits (or constant equivalence) propagation.


More information about the Gcc-bugs mailing list