[Bug tree-optimization/79547] duplicate strlen calls with same argument not folded

["jakub at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79547

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #3)
> +      /* Pure functions that return something not based on any object.  */
> +      case BUILT_IN_STRLEN:
> +       /* We don't need to do anything here.  No constraints are necessary
> +          for the return value and call handling for pure functions is
> +          special-cased in the alias oracle.  */
> +       return true;
>        /* Trampolines are special - they set up passing the static
>          frame.  */
>        case BUILT_IN_INIT_TRAMPOLINE:
> 
> 
> any other similar (pure/const) builtins?

strcmp, strncmp, strcasecmp, strncasecmp, memcmp, strchr, strrchr, index,
rindex?