On Tue, 19 Sep 2023, Jiufu Guo wrote:
> Hi,
>
> In r14-3582, an "overflow_free_p" interface is added.
> The pattern of "(t * 2) / 2" in match.pd can be simplified
> by using this interface.
>
> Bootstrap & regtest pass on ppc64{,le} and x86_64.
> Is this ok for trunk?
>
> BR,
> Jeff (Jiufu)
>
> gcc/ChangeLog:
>
> * match.pd ((t * 2) / 2): Update to use overflow_free_p.
>
> ---
> gcc/match.pd | 37 +++++++------------------------------
> 1 file changed, 7 insertions(+), 30 deletions(-)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index 87edf0e75c3..8bba7056000 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -926,36 +926,13 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> (if (TYPE_OVERFLOW_UNDEFINED (type))
> @0
> #if GIMPLE
> - (with
> - {
> - bool overflowed = true;
> - value_range vr0, vr1;
> - if (INTEGRAL_TYPE_P (type)
> - && get_range_query (cfun)->range_of_expr (vr0, @0)
> - && get_range_query (cfun)->range_of_expr (vr1, @1)
> - && !vr0.varying_p () && !vr0.undefined_p ()
> - && !vr1.varying_p () && !vr1.undefined_p ())
> - {
> - wide_int wmin0 = vr0.lower_bound ();
> - wide_int wmax0 = vr0.upper_bound ();
> - wide_int wmin1 = vr1.lower_bound ();
> - wide_int wmax1 = vr1.upper_bound ();
> - /* If the multiplication can't overflow/wrap around, then
> - it can be optimized too. */
> - wi::overflow_type min_ovf, max_ovf;
> - wi::mul (wmin0, wmin1, TYPE_SIGN (type), &min_ovf);
> - wi::mul (wmax0, wmax1, TYPE_SIGN (type), &max_ovf);
> - if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> - {
> - wi::mul (wmin0, wmax1, TYPE_SIGN (type), &min_ovf);
> - wi::mul (wmax0, wmin1, TYPE_SIGN (type), &max_ovf);
> - if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> - overflowed = false;
> - }
> - }
> - }
> - (if (!overflowed)
> - @0))
> + (with {value_range vr0, vr1;}
> + (if (INTEGRAL_TYPE_P (type)
> + && get_range_query (cfun)->range_of_expr (vr0, @0)
> + && get_range_query (cfun)->range_of_expr (vr1, @1)
> + && !vr0.varying_p () && !vr1.varying_p ()
>From your other uses checking !varying_p doesn't seem necessary?
OK with omitting.
Richard.
> + && range_op_handler (MULT_EXPR).overflow_free_p (vr0, vr1))
> + @0))
> #endif
> ))))
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
