Re: [COMMITTED] PR c++/106654 - Add assume support to VRP.

[Jakub Jelinek <jakub@redhat.com>]

On Wed, Oct 19, 2022 at 08:37:57PM -0400, Andrew MacLeod wrote:
> This patch adds basic support for ASSUME functions to VRP.
> 
> Based on the previous set of patches, Ive cleaned them up, and this provides
> the basic support from rangers generalized model. It does not support
> non-ssa name parameters, I think you might be on your own for that.
> 
> I modified Jakubs assumption pass to use GORI to query parameter rangers in
> assumption functions and set the global range for those, and then ranger's
> infer infrastructure is used to inject these rangers at assume call
> locations in VRP.
> 
> I also added an optimization testcase that tests the basic functionality in
> VRP2.  For instance it can reduce:
> 
> int
> f2 (int x, int y, int z)
> {
>   [[assume (x+12 == 14 && y >= 0 && y + 10 < 13 && z + 4 >= 4 && z - 2 <
> 18)]];
>   unsigned q = x + y + z;
>   if (q*2 > 46)
>     return 0;
>   return 1;
> }
> 
> to:
> 
> return 1;
> 
> 
> Its good to get us going, bt I think theres still lots of room for
> improvement.
> 
> Bootstraps on x86_64-pc-linux-gnu with no regressions.  Pushed.

Thanks.

	Jakub