https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105532

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot 
gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I am going to take care of this at least for GCC 13.

There is another invalid use here too:
/* Common POPCOUNT/PARITY simplifications.  */
/* popcount(X&C1) is (X>>C2)&1 when C1 == 1<<C2.  Same for parity(X&C1).  */
(for pfun (POPCOUNT PARITY)
  (simplify
    (pfun @0)
    (with { wide_int nz = tree_nonzero_bits (@0); }
      (switch
        (if (nz == 1)
          (convert @0))
        (if (wi::popcount (nz) == 1)
          (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
            (convert (rshift:utype (convert:utype @0)
                                   { build_int_cst (integer_type_node,
                                                    wi::ctz (nz)); }))))))))

Found while running the testsuite on x86_64.

Another one:
/* POPCOUNT simplifications.  */
/* popcount(X) + popcount(Y) is popcount(X|Y) when X&Y must be zero.  */
(simplify
  (plus (POPCOUNT:s @0) (POPCOUNT:s @1))
  (if (wi::bit_and (tree_nonzero_bits (@0), tree_nonzero_bits (@1)) == 0)
    (POPCOUNT (bit_ior @0 @1))))


Those 3 are only ones I see in match.pd (the other uses of tree_nonzero_bits
checks the type before the call).

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