On 7/31/23 18:47, Martin Jambor wrote:
> Hello,
> 
> On Tue, Jul 18 2023, Aldy Hernandez wrote:
>> On 7/17/23 15:14, Aldy Hernandez wrote:
>>> Instead of reading the known zero bits in IPA, read the value/mask
>>> pair which is available.
>>>
>>> There is a slight change of behavior here.  I have removed the check
>>> for SSA_NAME, as the ranger can calculate the range and value/mask for
>>> INTEGER_CST.  This simplifies the code a bit, since there's no special
>>> casing when setting the jfunc bits.  The default range for VR is
>>> undefined, so I think it's safe just to check for undefined_p().
>>
>> Final round of tests revealed a regression for which I've adjusted the
>> testcase.
>>
>> It turns out g++.dg/ipa/pure-const-3.C fails because IPA can now pick up
>> value/mask from any pass that has an integrated ranger.  The test was
>> previously disabling evrp and CCP, but now VRP[12], jump threading, and
>> DOM can make value/mask adjustments visible to IPA so they must be
>> disabled as well.
> 
> So can this be then converted into a new testcase that would test that
> we can now derive something we could not in the past?

Good idea.

This is what I'm testing.  I'm basically testing for "Propagated bits" 
in the ipa-cp pass which is where we are able to propagate more things.

I will commit if it succeeds.

Thanks.
Aldy