Re: [PATCH] MATCH: Add pattern for `signbit(x) ? x : -x` into abs (and swapped)

[Alexander Monakov via Gcc-patches]

On Sat, 13 May 2023, Andrew Pinski via Gcc-patches wrote:

> +/* signbit(x) != 0 ? -x : x -> abs(x)
> +   signbit(x) == 0 ? -x : x -> -abs(x) */
> +(for sign (SIGNBIT)

Surprised to see a dummy iterator here. Was this meant to include
float and long double versions of the builtin too (SIGNBITF and SIGNBITL)?

> + (for neeq (ne eq)
> +  (simplify
> +   (cond (neeq (sign @0) integer_zerop) (negate @0) @0)
> +    (if (neeq == NE_EXPR)
> +     (abs @0)
> +     (negate (abs @0))))))
> +
>  (simplify
>   /* signbit(x) -> 0 if x is nonnegative.  */
>   (SIGNBIT tree_expr_nonnegative_p@0)

Thanks.
Alexander