Hi,
Richard Biener <rguent...@suse.de> writes:
> 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?
Thanks for pointing out this!!
Yes, !varying_p is not needed, overflow_free_p could cover it.
Committed via r14-4191.
BR,
Jeff (Jiufu Guo)
>
> OK with omitting.
>
> Richard.
>
>> + && range_op_handler (MULT_EXPR).overflow_free_p (vr0, vr1))
>> + @0))
>> #endif
>> ))))
>>
>>
