On 11/8/18 7:44 AM, Aldy Hernandez wrote: > > > On 11/8/18 9:41 AM, Richard Biener wrote: >> On Thu, Nov 8, 2018 at 3:05 PM Aldy Hernandez <al...@redhat.com> wrote: >>> >>> >>> >>> On 11/8/18 8:59 AM, Richard Biener wrote: >>>> On Thu, Nov 8, 2018 at 12:52 PM Aldy Hernandez <al...@redhat.com> >>>> wrote: >>>>> >>>>> get/set_range_info() currently returns the extremes of a range. I >>>>> have >>>>> implemented overloaded variants that return a proper range. In the >>>>> future we should use actual ranges throughout, and not depend on range >>>>> extremes, as depending on this behavior could causes us to lose >>>>> precision. >>>>> >>>>> I am also including changes to size_must_be_zero_p() to show how we >>>>> should be using the range API, as opposed to performing error prone >>>>> ad-hoc calculations on ranges and anti-ranges. >>>> >>>> Yeah, I've been talking this all along but not being heard... >>> >>> My girlfriend says I don't listen. It could be related. >>> >>>>> Martin, I'm not saying your code is wrong. There are numerous other >>>>> places in the compiler where we manipulate ranges/anti-ranges >>>>> directly, >>>>> all of which should be adapted in the future. Everywhere there is a >>>>> mention of VR_RANGE/VR_ANTI_RANGE in the compiler is suspect. We >>>>> should >>>>> ideally be using intersect/union/may_contain_p/null_p, etc. >>>> >>>> null_p is a bad name btw, I just confused it with empty_p ... (which >>>> we have >>>> as undefined_p). contains_only_zero_p would be less confusing. >>> >>> Yes, a horrible name. I noticed so as I debugged precisely this bit. >>> How about zero_p? >> >> Probably the same ambiguous connotation? But yes, way better than >> null_p. > > Well...for starters I started with the nomenclature already in VRP which > was range_is_null. Probably due to using it for NULL pointer test elimination. But yea, in retrospect it's an awful name.
> > Also, how is zero_p() ambiguous? We want to know if the range is [0, > 0]. That reads pretty obvious to me. Seems reasonable to me. THe question is will we push that name into all the other places that use "null" when discussing ranges like ~[0,0] or ranges that ultimately include [0,0]. Not all of these are in [E]VRP IIRC. jeff
