[Bug tree-optimization/115484] [13/14/15 regression] if-to-switch prevents AVX vectorization

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115484

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Sam James from comment #2)
> GCC 8 vectorises it: https://godbolt.org/z/Y8Pvxsh5c.

The if-to-switch was not until GCC 11: r11-5605-g03eb09292ef228.
What made GCC 9 fail was the conversion from bool to int though:
/app/example.c:2:5: missed:   not vectorized: relevant stmt not supported:
patt_29 = (int) patt_30;

But that worked in GCC 8. Though that was fixed in GCC 11.

If you replace `c|=` with:
```
                c |=  (*s == ',' | *s == '|' | *s == '!' | *s == '*');
```

GCC 11+ is able to vectorize it again. But the original testcase fails now due
to if-to-switch .