[Bug tree-optimization/119402] [14/15 Regression] `((-bool) & _6) & (~_6)` is not optimized to 0 on some targets since r14-5673

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119402

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
```
(simplify
 (bit_and:c (mult:c zero_one_valued_p @0) @1)
 (with { bool wascmp; }
  (if (bitwise_inverted_equal_p (@0, @1, wascmp))
   { build_zero_cst (type); })))
```


Or maybe just
```
(simplify
 (bit_and:c (mult:c zero_one_valued_p@2 @0) @1)
 (mult @2 (bit_and @0 @1))
```

Still deciding if we want ! on the bit_and or not.


Is enough and allows to optimize even:
```
unsigned x(_Bool iftmp, unsigned _6)
{
        return (iftmp * _6) & (_6);
}
```

Most likely also should handle this inside re-association and turn
zero_one_valued_p*b into (-zero_one_valued_p) & b to allow re-association too
so that:
unsigned x(_Bool iftmp, unsigned _6, unsigned _7)
{
        return (iftmp * _6) & ((_7) & ~_6);
}

Is optimized too.