| Message ID | 6cbe0075-0250-ae99-7a2b-2198cecd40c4@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add value_range_base::contains_p | expand |
On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> wrote: > > This patch cleans up the various contains, may_contain, and > value_inside_range variants we have throughout, in favor of one-- > contains_p. There should be no changes in functionality. > > I have added a note to range_includes_zero_p, perhaps as a personal > question than anything else. This function was/is returning true for > UNDEFINED. From a semantic sense, that doesn't make sense. UNDEFINED > is really the empty set. Is the functionality wrong, or should we call > this function something else? Either way, I'm fine removing the comment > but I'm genuinely curious. So this affects for example this hunk: - if (vr && !range_includes_p (vr, 1)) + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) + && !vr->undefined_p ())) { I think it's arbitrary how we compute X in UNDEFINED and I'm fine with changing the affected predicates to return false. This means not testing for !vr->undefined_p here. Note I very much dislike the build_one_cst () call here so please provide an overload hiding this. Not sure why you keep range_includes_zero_p. Richard. > > OK?
On 6/11/19 9:45 AM, Richard Biener wrote: > On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> wrote: >> >> This patch cleans up the various contains, may_contain, and >> value_inside_range variants we have throughout, in favor of one-- >> contains_p. There should be no changes in functionality. >> >> I have added a note to range_includes_zero_p, perhaps as a personal >> question than anything else. This function was/is returning true for >> UNDEFINED. From a semantic sense, that doesn't make sense. UNDEFINED >> is really the empty set. Is the functionality wrong, or should we call >> this function something else? Either way, I'm fine removing the comment >> but I'm genuinely curious. > > So this affects for example this hunk: > > - if (vr && !range_includes_p (vr, 1)) > + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) > + && !vr->undefined_p ())) > { > > I think it's arbitrary how we compute X in UNDEFINED and I'm fine > with changing the affected predicates to return false. This means > not testing for !vr->undefined_p here. Excellent. > > Note I very much dislike the build_one_cst () call here so please > provide an overload hiding this. Good idea. I love it. > > Not sure why you keep range_includes_zero_p. I wasn't sure if there was some subtle reason why we were including undefined. OK pending tests?
On 6/11/19 9:05 AM, Aldy Hernandez wrote: > > > On 6/11/19 9:45 AM, Richard Biener wrote: >> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> wrote: >>> >>> This patch cleans up the various contains, may_contain, and >>> value_inside_range variants we have throughout, in favor of one-- >>> contains_p. There should be no changes in functionality. >>> >>> I have added a note to range_includes_zero_p, perhaps as a personal >>> question than anything else. This function was/is returning true for >>> UNDEFINED. From a semantic sense, that doesn't make sense. UNDEFINED >>> is really the empty set. Is the functionality wrong, or should we call >>> this function something else? Either way, I'm fine removing the comment >>> but I'm genuinely curious. >> >> So this affects for example this hunk: >> >> - if (vr && !range_includes_p (vr, 1)) >> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >> + && !vr->undefined_p ())) >> { >> >> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >> with changing the affected predicates to return false. This means >> not testing for !vr->undefined_p here. > > Excellent. > >> >> Note I very much dislike the build_one_cst () call here so please >> provide an overload hiding this. > > Good idea. I love it. > >> >> Not sure why you keep range_includes_zero_p. > > I wasn't sure if there was some subtle reason why we were including > undefined. > > OK pending tests? Should the second overload: + bool contains_p (tree) const; + bool contains_p (int) const; take something like HOST_WIDE_INT or even one of those poly_ints like build_int_cst does? (With the former, contains_p (0) will likely be ambiguous since 0 is int and HOST_WIDE_INT is long). Martin
On 6/11/19 12:17 PM, Martin Sebor wrote: > On 6/11/19 9:05 AM, Aldy Hernandez wrote: >> >> >> On 6/11/19 9:45 AM, Richard Biener wrote: >>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> >>> wrote: >>>> >>>> This patch cleans up the various contains, may_contain, and >>>> value_inside_range variants we have throughout, in favor of one-- >>>> contains_p. There should be no changes in functionality. >>>> >>>> I have added a note to range_includes_zero_p, perhaps as a personal >>>> question than anything else. This function was/is returning true for >>>> UNDEFINED. From a semantic sense, that doesn't make sense. UNDEFINED >>>> is really the empty set. Is the functionality wrong, or should we call >>>> this function something else? Either way, I'm fine removing the >>>> comment >>>> but I'm genuinely curious. >>> >>> So this affects for example this hunk: >>> >>> - if (vr && !range_includes_p (vr, 1)) >>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >>> + && !vr->undefined_p ())) >>> { >>> >>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >>> with changing the affected predicates to return false. This means >>> not testing for !vr->undefined_p here. >> >> Excellent. >> >>> >>> Note I very much dislike the build_one_cst () call here so please >>> provide an overload hiding this. >> >> Good idea. I love it. >> >>> >>> Not sure why you keep range_includes_zero_p. >> >> I wasn't sure if there was some subtle reason why we were including >> undefined. >> >> OK pending tests? > > Should the second overload: > > + bool contains_p (tree) const; > + bool contains_p (int) const; > > take something like HOST_WIDE_INT or even one of those poly_ints > like build_int_cst does? (With the former, contains_p (0) will > likely be ambiguous since 0 is int and HOST_WIDE_INT is long). We have a type, so there should be no confusion: + return contains_p (build_int_cst (type (), val)); (UNDEFINED and VARYING don't have a type, so they are special cased prior). Aldy
On 6/11/19 10:26 AM, Aldy Hernandez wrote: > > > On 6/11/19 12:17 PM, Martin Sebor wrote: >> On 6/11/19 9:05 AM, Aldy Hernandez wrote: >>> >>> >>> On 6/11/19 9:45 AM, Richard Biener wrote: >>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> >>>> wrote: >>>>> >>>>> This patch cleans up the various contains, may_contain, and >>>>> value_inside_range variants we have throughout, in favor of one-- >>>>> contains_p. There should be no changes in functionality. >>>>> >>>>> I have added a note to range_includes_zero_p, perhaps as a personal >>>>> question than anything else. This function was/is returning true for >>>>> UNDEFINED. From a semantic sense, that doesn't make sense. UNDEFINED >>>>> is really the empty set. Is the functionality wrong, or should we >>>>> call >>>>> this function something else? Either way, I'm fine removing the >>>>> comment >>>>> but I'm genuinely curious. >>>> >>>> So this affects for example this hunk: >>>> >>>> - if (vr && !range_includes_p (vr, 1)) >>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >>>> + && !vr->undefined_p ())) >>>> { >>>> >>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >>>> with changing the affected predicates to return false. This means >>>> not testing for !vr->undefined_p here. >>> >>> Excellent. >>> >>>> >>>> Note I very much dislike the build_one_cst () call here so please >>>> provide an overload hiding this. >>> >>> Good idea. I love it. >>> >>>> >>>> Not sure why you keep range_includes_zero_p. >>> >>> I wasn't sure if there was some subtle reason why we were including >>> undefined. >>> >>> OK pending tests? >> >> Should the second overload: >> >> + bool contains_p (tree) const; >> + bool contains_p (int) const; >> >> take something like HOST_WIDE_INT or even one of those poly_ints >> like build_int_cst does? (With the former, contains_p (0) will >> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). > > We have a type, so there should be no confusion: > > + return contains_p (build_int_cst (type (), val)); > > (UNDEFINED and VARYING don't have a type, so they are special cased prior). I didn't mean the overloads are confusing, just that there the one that takes an int doesn't make it possible to test whether a value outside the range of an int is in the range. For example, in the call contains_p (SIZE_MAX) the argument will get sliced (and trigger a -Woverflow). One will need to go back to the more verbose way of calling it. Changing the argument type to HOST_WIDE_INT would avoid the slicing and warning but then make contains_p (0) ambiguous because 0 isn't a perfect match for either void* or long (so it requires a conversion). Martin > > Aldy
On 6/11/19 12:52 PM, Martin Sebor wrote: > On 6/11/19 10:26 AM, Aldy Hernandez wrote: >> >> >> On 6/11/19 12:17 PM, Martin Sebor wrote: >>> On 6/11/19 9:05 AM, Aldy Hernandez wrote: >>>> >>>> >>>> On 6/11/19 9:45 AM, Richard Biener wrote: >>>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> >>>>> wrote: >>>>>> >>>>>> This patch cleans up the various contains, may_contain, and >>>>>> value_inside_range variants we have throughout, in favor of one-- >>>>>> contains_p. There should be no changes in functionality. >>>>>> >>>>>> I have added a note to range_includes_zero_p, perhaps as a personal >>>>>> question than anything else. This function was/is returning true for >>>>>> UNDEFINED. From a semantic sense, that doesn't make sense. >>>>>> UNDEFINED >>>>>> is really the empty set. Is the functionality wrong, or should we >>>>>> call >>>>>> this function something else? Either way, I'm fine removing the >>>>>> comment >>>>>> but I'm genuinely curious. >>>>> >>>>> So this affects for example this hunk: >>>>> >>>>> - if (vr && !range_includes_p (vr, 1)) >>>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >>>>> + && !vr->undefined_p ())) >>>>> { >>>>> >>>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >>>>> with changing the affected predicates to return false. This means >>>>> not testing for !vr->undefined_p here. >>>> >>>> Excellent. >>>> >>>>> >>>>> Note I very much dislike the build_one_cst () call here so please >>>>> provide an overload hiding this. >>>> >>>> Good idea. I love it. >>>> >>>>> >>>>> Not sure why you keep range_includes_zero_p. >>>> >>>> I wasn't sure if there was some subtle reason why we were including >>>> undefined. >>>> >>>> OK pending tests? >>> >>> Should the second overload: >>> >>> + bool contains_p (tree) const; >>> + bool contains_p (int) const; >>> >>> take something like HOST_WIDE_INT or even one of those poly_ints >>> like build_int_cst does? (With the former, contains_p (0) will >>> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). >> >> We have a type, so there should be no confusion: >> >> + return contains_p (build_int_cst (type (), val)); >> >> (UNDEFINED and VARYING don't have a type, so they are special cased >> prior). > > I didn't mean the overloads are confusing, just that there the one > that takes an int doesn't make it possible to test whether a value > outside the range of an int is in the range. For example, in > the call > > contains_p (SIZE_MAX) > > the argument will get sliced (and trigger a -Woverflow). One will > need to go back to the more verbose way of calling it. The int version is not really meant to pass anything but simple constants. For anything fancy, one should really be using the tree version. But I can certainly change the argument to HOST_WIDE_INT if preferred. > > Changing the argument type to HOST_WIDE_INT would avoid the slicing > and warning but then make contains_p (0) ambiguous because 0 isn't > a perfect match for either void* or long (so it requires a conversion). Just a plain 0 will match the int version, instead of the tree version, right? Nobody should be passing NULL to the tree version, so that seems like a non-issue. Aldy
On 6/11/19 3:02 PM, Aldy Hernandez wrote: > > > On 6/11/19 12:52 PM, Martin Sebor wrote: >> On 6/11/19 10:26 AM, Aldy Hernandez wrote: >>> >>> >>> On 6/11/19 12:17 PM, Martin Sebor wrote: >>>> On 6/11/19 9:05 AM, Aldy Hernandez wrote: >>>>> >>>>> >>>>> On 6/11/19 9:45 AM, Richard Biener wrote: >>>>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> >>>>>> wrote: >>>>>>> >>>>>>> This patch cleans up the various contains, may_contain, and >>>>>>> value_inside_range variants we have throughout, in favor of one-- >>>>>>> contains_p. There should be no changes in functionality. >>>>>>> >>>>>>> I have added a note to range_includes_zero_p, perhaps as a personal >>>>>>> question than anything else. This function was/is returning true >>>>>>> for >>>>>>> UNDEFINED. From a semantic sense, that doesn't make sense. >>>>>>> UNDEFINED >>>>>>> is really the empty set. Is the functionality wrong, or should >>>>>>> we call >>>>>>> this function something else? Either way, I'm fine removing the >>>>>>> comment >>>>>>> but I'm genuinely curious. >>>>>> >>>>>> So this affects for example this hunk: >>>>>> >>>>>> - if (vr && !range_includes_p (vr, 1)) >>>>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >>>>>> + && !vr->undefined_p ())) >>>>>> { >>>>>> >>>>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >>>>>> with changing the affected predicates to return false. This means >>>>>> not testing for !vr->undefined_p here. >>>>> >>>>> Excellent. >>>>> >>>>>> >>>>>> Note I very much dislike the build_one_cst () call here so please >>>>>> provide an overload hiding this. >>>>> >>>>> Good idea. I love it. >>>>> >>>>>> >>>>>> Not sure why you keep range_includes_zero_p. >>>>> >>>>> I wasn't sure if there was some subtle reason why we were including >>>>> undefined. >>>>> >>>>> OK pending tests? >>>> >>>> Should the second overload: >>>> >>>> + bool contains_p (tree) const; >>>> + bool contains_p (int) const; >>>> >>>> take something like HOST_WIDE_INT or even one of those poly_ints >>>> like build_int_cst does? (With the former, contains_p (0) will >>>> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). >>> >>> We have a type, so there should be no confusion: >>> >>> + return contains_p (build_int_cst (type (), val)); >>> >>> (UNDEFINED and VARYING don't have a type, so they are special cased >>> prior). >> >> I didn't mean the overloads are confusing, just that there the one >> that takes an int doesn't make it possible to test whether a value >> outside the range of an int is in the range. For example, in >> the call >> >> contains_p (SIZE_MAX) >> >> the argument will get sliced (and trigger a -Woverflow). One will >> need to go back to the more verbose way of calling it. > > The int version is not really meant to pass anything but simple > constants. For anything fancy, one should really be using the tree > version. But I can certainly change the argument to HOST_WIDE_INT if > preferred. > >> >> Changing the argument type to HOST_WIDE_INT would avoid the slicing >> and warning but then make contains_p (0) ambiguous because 0 isn't >> a perfect match for either void* or long (so it requires a conversion). > > Just a plain 0 will match the int version, instead of the tree version, > right? Nobody should be passing NULL to the tree version, so that seems > like a non-issue. Right, NULL isn't a problem, but I would expect any integer to work (I thought that's what Richard was asking for) So my suggestion was to have contains_p() a poly_int64 and provide just as robust an API as build_int_cst. The argument ends up converted to the poly_int64 anyway when it's passed to the latter. I.e., why not define contains_p simply like this: bool value_range_base::contains_p (poly_int64 val) const { if (varying_p ()) return true; if (undefined_p ()) return false; return contains_p (build_int_cst (type (), val)); } Martin
On Wed, Jun 12, 2019 at 1:57 AM Martin Sebor <msebor@gmail.com> wrote: > > On 6/11/19 3:02 PM, Aldy Hernandez wrote: > > > > > > On 6/11/19 12:52 PM, Martin Sebor wrote: > >> On 6/11/19 10:26 AM, Aldy Hernandez wrote: > >>> > >>> > >>> On 6/11/19 12:17 PM, Martin Sebor wrote: > >>>> On 6/11/19 9:05 AM, Aldy Hernandez wrote: > >>>>> > >>>>> > >>>>> On 6/11/19 9:45 AM, Richard Biener wrote: > >>>>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> > >>>>>> wrote: > >>>>>>> > >>>>>>> This patch cleans up the various contains, may_contain, and > >>>>>>> value_inside_range variants we have throughout, in favor of one-- > >>>>>>> contains_p. There should be no changes in functionality. > >>>>>>> > >>>>>>> I have added a note to range_includes_zero_p, perhaps as a personal > >>>>>>> question than anything else. This function was/is returning true > >>>>>>> for > >>>>>>> UNDEFINED. From a semantic sense, that doesn't make sense. > >>>>>>> UNDEFINED > >>>>>>> is really the empty set. Is the functionality wrong, or should > >>>>>>> we call > >>>>>>> this function something else? Either way, I'm fine removing the > >>>>>>> comment > >>>>>>> but I'm genuinely curious. > >>>>>> > >>>>>> So this affects for example this hunk: > >>>>>> > >>>>>> - if (vr && !range_includes_p (vr, 1)) > >>>>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) > >>>>>> + && !vr->undefined_p ())) > >>>>>> { > >>>>>> > >>>>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine > >>>>>> with changing the affected predicates to return false. This means > >>>>>> not testing for !vr->undefined_p here. > >>>>> > >>>>> Excellent. > >>>>> > >>>>>> > >>>>>> Note I very much dislike the build_one_cst () call here so please > >>>>>> provide an overload hiding this. > >>>>> > >>>>> Good idea. I love it. > >>>>> > >>>>>> > >>>>>> Not sure why you keep range_includes_zero_p. > >>>>> > >>>>> I wasn't sure if there was some subtle reason why we were including > >>>>> undefined. > >>>>> > >>>>> OK pending tests? > >>>> > >>>> Should the second overload: > >>>> > >>>> + bool contains_p (tree) const; > >>>> + bool contains_p (int) const; > >>>> > >>>> take something like HOST_WIDE_INT or even one of those poly_ints > >>>> like build_int_cst does? (With the former, contains_p (0) will > >>>> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). > >>> > >>> We have a type, so there should be no confusion: > >>> > >>> + return contains_p (build_int_cst (type (), val)); > >>> > >>> (UNDEFINED and VARYING don't have a type, so they are special cased > >>> prior). > >> > >> I didn't mean the overloads are confusing, just that there the one > >> that takes an int doesn't make it possible to test whether a value > >> outside the range of an int is in the range. For example, in > >> the call > >> > >> contains_p (SIZE_MAX) > >> > >> the argument will get sliced (and trigger a -Woverflow). One will > >> need to go back to the more verbose way of calling it. > > > > The int version is not really meant to pass anything but simple > > constants. For anything fancy, one should really be using the tree > > version. But I can certainly change the argument to HOST_WIDE_INT if > > preferred. > > > >> > >> Changing the argument type to HOST_WIDE_INT would avoid the slicing > >> and warning but then make contains_p (0) ambiguous because 0 isn't > >> a perfect match for either void* or long (so it requires a conversion). > > > > Just a plain 0 will match the int version, instead of the tree version, > > right? Nobody should be passing NULL to the tree version, so that seems > > like a non-issue. > > Right, NULL isn't a problem, but I would expect any integer to work > (I thought that's what Richard was asking for) So my suggestion was > to have contains_p() a poly_int64 and provide just as robust an API > as build_int_cst. The argument ends up converted to the poly_int64 > anyway when it's passed to the latter. I.e., why not define > contains_p simply like this: > > bool > value_range_base::contains_p (poly_int64 val) const > { > if (varying_p ()) > return true; > if (undefined_p ()) > return false; > > return contains_p (build_int_cst (type (), val)); > } I agree that plain 'int' is bad. Given we currently store INTEGER_CSTs only (and not POLY_INT_CSTs) a widest_int argument should be fine. Note widest because when interpreted signed all unsigned values fit. The existing contains_p check is also a bit fishy for the cases TREE_TYPE of the value has a value-range not covered in the value-ranges type... I guess it could do if (!int_fits_type_p (val, this->type ()) return false; but that changes existing behavior which happily throws different sign constants into tree_int_cst_lt for example... Do we want to allow non-INTEGER_CST val arguments at all? That is, you make contains_p return a bool and say "yes" when we couldn't really decide. This is why previously it was named may_contain_p (and we didn't have must_contain_p). I think making the result explicitely clear is a must since contains_p reads like !contains_p means it does _not_ contain. So, either change back the name (and provide the must variant) or make it return the tri-state from value_inside_range. Richard. > Martin
On 6/12/19 5:33 AM, Richard Biener wrote: > On Wed, Jun 12, 2019 at 1:57 AM Martin Sebor <msebor@gmail.com> wrote: >> >> On 6/11/19 3:02 PM, Aldy Hernandez wrote: >>> >>> >>> On 6/11/19 12:52 PM, Martin Sebor wrote: >>>> On 6/11/19 10:26 AM, Aldy Hernandez wrote: >>>>> >>>>> >>>>> On 6/11/19 12:17 PM, Martin Sebor wrote: >>>>>> On 6/11/19 9:05 AM, Aldy Hernandez wrote: >>>>>>> >>>>>>> >>>>>>> On 6/11/19 9:45 AM, Richard Biener wrote: >>>>>>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> >>>>>>>> wrote: >>>>>>>>> >>>>>>>>> This patch cleans up the various contains, may_contain, and >>>>>>>>> value_inside_range variants we have throughout, in favor of one-- >>>>>>>>> contains_p. There should be no changes in functionality. >>>>>>>>> >>>>>>>>> I have added a note to range_includes_zero_p, perhaps as a personal >>>>>>>>> question than anything else. This function was/is returning true >>>>>>>>> for >>>>>>>>> UNDEFINED. From a semantic sense, that doesn't make sense. >>>>>>>>> UNDEFINED >>>>>>>>> is really the empty set. Is the functionality wrong, or should >>>>>>>>> we call >>>>>>>>> this function something else? Either way, I'm fine removing the >>>>>>>>> comment >>>>>>>>> but I'm genuinely curious. >>>>>>>> >>>>>>>> So this affects for example this hunk: >>>>>>>> >>>>>>>> - if (vr && !range_includes_p (vr, 1)) >>>>>>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) >>>>>>>> + && !vr->undefined_p ())) >>>>>>>> { >>>>>>>> >>>>>>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine >>>>>>>> with changing the affected predicates to return false. This means >>>>>>>> not testing for !vr->undefined_p here. >>>>>>> >>>>>>> Excellent. >>>>>>> >>>>>>>> >>>>>>>> Note I very much dislike the build_one_cst () call here so please >>>>>>>> provide an overload hiding this. >>>>>>> >>>>>>> Good idea. I love it. >>>>>>> >>>>>>>> >>>>>>>> Not sure why you keep range_includes_zero_p. >>>>>>> >>>>>>> I wasn't sure if there was some subtle reason why we were including >>>>>>> undefined. >>>>>>> >>>>>>> OK pending tests? >>>>>> >>>>>> Should the second overload: >>>>>> >>>>>> + bool contains_p (tree) const; >>>>>> + bool contains_p (int) const; >>>>>> >>>>>> take something like HOST_WIDE_INT or even one of those poly_ints >>>>>> like build_int_cst does? (With the former, contains_p (0) will >>>>>> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). >>>>> >>>>> We have a type, so there should be no confusion: >>>>> >>>>> + return contains_p (build_int_cst (type (), val)); >>>>> >>>>> (UNDEFINED and VARYING don't have a type, so they are special cased >>>>> prior). >>>> >>>> I didn't mean the overloads are confusing, just that there the one >>>> that takes an int doesn't make it possible to test whether a value >>>> outside the range of an int is in the range. For example, in >>>> the call >>>> >>>> contains_p (SIZE_MAX) >>>> >>>> the argument will get sliced (and trigger a -Woverflow). One will >>>> need to go back to the more verbose way of calling it. >>> >>> The int version is not really meant to pass anything but simple >>> constants. For anything fancy, one should really be using the tree >>> version. But I can certainly change the argument to HOST_WIDE_INT if >>> preferred. >>> >>>> >>>> Changing the argument type to HOST_WIDE_INT would avoid the slicing >>>> and warning but then make contains_p (0) ambiguous because 0 isn't >>>> a perfect match for either void* or long (so it requires a conversion). >>> >>> Just a plain 0 will match the int version, instead of the tree version, >>> right? Nobody should be passing NULL to the tree version, so that seems >>> like a non-issue. >> >> Right, NULL isn't a problem, but I would expect any integer to work >> (I thought that's what Richard was asking for) So my suggestion was >> to have contains_p() a poly_int64 and provide just as robust an API >> as build_int_cst. The argument ends up converted to the poly_int64 >> anyway when it's passed to the latter. I.e., why not define >> contains_p simply like this: >> >> bool >> value_range_base::contains_p (poly_int64 val) const >> { >> if (varying_p ()) >> return true; >> if (undefined_p ()) >> return false; >> >> return contains_p (build_int_cst (type (), val)); >> } > > I agree that plain 'int' is bad. Given we currently store > INTEGER_CSTs only (and not POLY_INT_CSTs) a > widest_int argument should be fine. Note widest > because when interpreted signed all unsigned values > fit. > > The existing contains_p check is also a bit fishy > for the cases TREE_TYPE of the value has a > value-range not covered in the value-ranges type... > I guess it could do > > if (!int_fits_type_p (val, this->type ()) > return false; > > but that changes existing behavior which happily > throws different sign constants into tree_int_cst_lt > for example... Do we want to allow non-INTEGER_CST > val arguments at all? That is, you make contains_p > return a bool and say "yes" when we couldn't really > decide. This is why previously it was named > may_contain_p (and we didn't have must_contain_p). > I think making the result explicitely clear is a must > since contains_p reads like !contains_p means > it does _not_ contain. So, either change back the > name (and provide the must variant) > or make it return the tri-state from value_inside_range. The only reason I added the int overload was because you didn't like the build_one_cst call. However, if we make it HOST_WIDE_INT or even widest_int, it will cause a conflict resolution with the tree version. I think it's best we only provide a tree version, and make due with the one call to build_one_cst. There is still the range_includes_zero_p() convenience function that takes care of the common case. I see what you mean with the may/must problem. We don't have that problem in the ranger because we only deal with constants, and there is never ambiguity. Since we don't have any consumers of must_contain_p yet, let's leave this bit for later discussion when it's actually needed. What I propose then is a general clean up of may_contain_p, making value_inside_range a member function that deals with the range in THIS. We can remove value_inside_range, as it's only used from the one build_on-cst place, and range_includes_zero_p (which I've adjusted accordingly). Note. I've changed existing functionality to so that may_contains_p (and range_includes_zero_p accordingly) returns FALSE for VR_UNDEFINED. AFAIU, VR_UNDEFINED is the empty set, so we absolutely know it's not inside the range. I've tested my patch both with and without this VR_UNDEFINED changelet, and there are no regressions. With this cleanup, particularly with rewriting may_contain_p in terms of the now value_inside_range method, we can later provide must_contain_p when needed with just: bool value_range_base::must_contain_p (tree val) const { return value_inside_range (val) == 1; } OK?
On Wed, Jun 12, 2019 at 11:33 PM Aldy Hernandez <aldyh@redhat.com> wrote: > > On 6/12/19 5:33 AM, Richard Biener wrote: > > On Wed, Jun 12, 2019 at 1:57 AM Martin Sebor <msebor@gmail.com> wrote: > >> > >> On 6/11/19 3:02 PM, Aldy Hernandez wrote: > >>> > >>> > >>> On 6/11/19 12:52 PM, Martin Sebor wrote: > >>>> On 6/11/19 10:26 AM, Aldy Hernandez wrote: > >>>>> > >>>>> > >>>>> On 6/11/19 12:17 PM, Martin Sebor wrote: > >>>>>> On 6/11/19 9:05 AM, Aldy Hernandez wrote: > >>>>>>> > >>>>>>> > >>>>>>> On 6/11/19 9:45 AM, Richard Biener wrote: > >>>>>>>> On Tue, Jun 11, 2019 at 12:40 PM Aldy Hernandez <aldyh@redhat.com> > >>>>>>>> wrote: > >>>>>>>>> > >>>>>>>>> This patch cleans up the various contains, may_contain, and > >>>>>>>>> value_inside_range variants we have throughout, in favor of one-- > >>>>>>>>> contains_p. There should be no changes in functionality. > >>>>>>>>> > >>>>>>>>> I have added a note to range_includes_zero_p, perhaps as a personal > >>>>>>>>> question than anything else. This function was/is returning true > >>>>>>>>> for > >>>>>>>>> UNDEFINED. From a semantic sense, that doesn't make sense. > >>>>>>>>> UNDEFINED > >>>>>>>>> is really the empty set. Is the functionality wrong, or should > >>>>>>>>> we call > >>>>>>>>> this function something else? Either way, I'm fine removing the > >>>>>>>>> comment > >>>>>>>>> but I'm genuinely curious. > >>>>>>>> > >>>>>>>> So this affects for example this hunk: > >>>>>>>> > >>>>>>>> - if (vr && !range_includes_p (vr, 1)) > >>>>>>>> + if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name))) > >>>>>>>> + && !vr->undefined_p ())) > >>>>>>>> { > >>>>>>>> > >>>>>>>> I think it's arbitrary how we compute X in UNDEFINED and I'm fine > >>>>>>>> with changing the affected predicates to return false. This means > >>>>>>>> not testing for !vr->undefined_p here. > >>>>>>> > >>>>>>> Excellent. > >>>>>>> > >>>>>>>> > >>>>>>>> Note I very much dislike the build_one_cst () call here so please > >>>>>>>> provide an overload hiding this. > >>>>>>> > >>>>>>> Good idea. I love it. > >>>>>>> > >>>>>>>> > >>>>>>>> Not sure why you keep range_includes_zero_p. > >>>>>>> > >>>>>>> I wasn't sure if there was some subtle reason why we were including > >>>>>>> undefined. > >>>>>>> > >>>>>>> OK pending tests? > >>>>>> > >>>>>> Should the second overload: > >>>>>> > >>>>>> + bool contains_p (tree) const; > >>>>>> + bool contains_p (int) const; > >>>>>> > >>>>>> take something like HOST_WIDE_INT or even one of those poly_ints > >>>>>> like build_int_cst does? (With the former, contains_p (0) will > >>>>>> likely be ambiguous since 0 is int and HOST_WIDE_INT is long). > >>>>> > >>>>> We have a type, so there should be no confusion: > >>>>> > >>>>> + return contains_p (build_int_cst (type (), val)); > >>>>> > >>>>> (UNDEFINED and VARYING don't have a type, so they are special cased > >>>>> prior). > >>>> > >>>> I didn't mean the overloads are confusing, just that there the one > >>>> that takes an int doesn't make it possible to test whether a value > >>>> outside the range of an int is in the range. For example, in > >>>> the call > >>>> > >>>> contains_p (SIZE_MAX) > >>>> > >>>> the argument will get sliced (and trigger a -Woverflow). One will > >>>> need to go back to the more verbose way of calling it. > >>> > >>> The int version is not really meant to pass anything but simple > >>> constants. For anything fancy, one should really be using the tree > >>> version. But I can certainly change the argument to HOST_WIDE_INT if > >>> preferred. > >>> > >>>> > >>>> Changing the argument type to HOST_WIDE_INT would avoid the slicing > >>>> and warning but then make contains_p (0) ambiguous because 0 isn't > >>>> a perfect match for either void* or long (so it requires a conversion). > >>> > >>> Just a plain 0 will match the int version, instead of the tree version, > >>> right? Nobody should be passing NULL to the tree version, so that seems > >>> like a non-issue. > >> > >> Right, NULL isn't a problem, but I would expect any integer to work > >> (I thought that's what Richard was asking for) So my suggestion was > >> to have contains_p() a poly_int64 and provide just as robust an API > >> as build_int_cst. The argument ends up converted to the poly_int64 > >> anyway when it's passed to the latter. I.e., why not define > >> contains_p simply like this: > >> > >> bool > >> value_range_base::contains_p (poly_int64 val) const > >> { > >> if (varying_p ()) > >> return true; > >> if (undefined_p ()) > >> return false; > >> > >> return contains_p (build_int_cst (type (), val)); > >> } > > > > I agree that plain 'int' is bad. Given we currently store > > INTEGER_CSTs only (and not POLY_INT_CSTs) a > > widest_int argument should be fine. Note widest > > because when interpreted signed all unsigned values > > fit. > > > > The existing contains_p check is also a bit fishy > > for the cases TREE_TYPE of the value has a > > value-range not covered in the value-ranges type... > > I guess it could do > > > > if (!int_fits_type_p (val, this->type ()) > > return false; > > > > but that changes existing behavior which happily > > throws different sign constants into tree_int_cst_lt > > for example... Do we want to allow non-INTEGER_CST > > val arguments at all? That is, you make contains_p > > return a bool and say "yes" when we couldn't really > > decide. This is why previously it was named > > may_contain_p (and we didn't have must_contain_p). > > I think making the result explicitely clear is a must > > since contains_p reads like !contains_p means > > it does _not_ contain. So, either change back the > > name (and provide the must variant) > > or make it return the tri-state from value_inside_range. > > The only reason I added the int overload was because you didn't like the > build_one_cst call. However, if we make it HOST_WIDE_INT or even > widest_int, it will cause a conflict resolution with the tree version. > I think it's best we only provide a tree version, and make due with the > one call to build_one_cst. There is still the range_includes_zero_p() > convenience function that takes care of the common case. > > I see what you mean with the may/must problem. We don't have that > problem in the ranger because we only deal with constants, and there is > never ambiguity. Since we don't have any consumers of must_contain_p > yet, let's leave this bit for later discussion when it's actually needed. > > What I propose then is a general clean up of may_contain_p, making > value_inside_range a member function that deals with the range in THIS. > We can remove value_inside_range, as it's only used from the one > build_on-cst place, and range_includes_zero_p (which I've adjusted > accordingly). > > Note. I've changed existing functionality to so that may_contains_p > (and range_includes_zero_p accordingly) returns FALSE for VR_UNDEFINED. > AFAIU, VR_UNDEFINED is the empty set, so we absolutely know it's not > inside the range. I've tested my patch both with and without this > VR_UNDEFINED changelet, and there are no regressions. > > With this cleanup, particularly with rewriting may_contain_p in terms of > the now value_inside_range method, we can later provide must_contain_p > when needed with just: > > bool > value_range_base::must_contain_p (tree val) const > { > return value_inside_range (val) == 1; > } > > OK? OK. This is definitely an obvious improvement. As you say we can do more adjustments later. Richard.
commit eac5cbfa507146166498e395d9347efdf46d3ef4
Author: Aldy Hernandez <aldyh@redhat.com>
Date: Tue Jun 4 09:11:22 2019 +0200
value_range_base::contains_p and may_contains_p.
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bee0a75a000..4f5c1798751 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2019-06-11 Aldy Hernandez <aldyh@redhat.com>
+
+ * gimple-loop-versioning.cc (prune_loop_conditions): Use
+ value_range_base::contains_p.
+ * tree-vrp.c (value_range_base::may_contain_p): Remove.
+ (value_inside_range): Make private to value_range_base class.
+ (value_range_base::contains_p): New.
+ * tree-vrp.h (value_range_base): Remove may_contain_p. Add
+ contains_p. Add value_inside_range.
+ (range_includes_p): Remove.
+ (value_inside_range): Remove.
+ (range_includes_p): Use value_range_base::contains_p.
+ * vr-values.c (compare_range_with_value): Same.
+
2019-06-11 Aldy Hernandez <aldyh@redhat.com>
* gimple-ssa-evrp.c (evrp_dom_walker::before_dom_children): Use
diff --git a/gcc/gimple-loop-versioning.cc b/gcc/gimple-loop-versioning.cc
index a2f68bf08db..85468fa06c4 100644
--- a/gcc/gimple-loop-versioning.cc
+++ b/gcc/gimple-loop-versioning.cc
@@ -1489,7 +1489,8 @@ loop_versioning::prune_loop_conditions (struct loop *loop, vr_values *vrs)
{
tree name = ssa_name (i);
value_range *vr = vrs->get_value_range (name);
- if (vr && !range_includes_p (vr, 1))
+ if (vr && (!vr->contains_p (build_one_cst (TREE_TYPE (name)))
+ && !vr->undefined_p ()))
{
if (dump_enabled_p ())
dump_printf_loc (MSG_NOTE, find_loop_location (loop),
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 08e6c6b6111..58ca9fa0d34 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -292,25 +292,6 @@ value_range::set_varying (tree type)
equiv_clear ();
}
-/* Return TRUE if it is possible that range contains VAL. */
-
-bool
-value_range_base::may_contain_p (tree val) const
-{
- if (varying_p ())
- return true;
-
- if (undefined_p ())
- return true;
-
- if (m_kind == VR_ANTI_RANGE)
- {
- int res = value_inside_range (val, min (), max ());
- return res == 0 || res == -2;
- }
- return value_inside_range (val, min (), max ()) != 0;
-}
-
void
value_range::equiv_clear ()
{
@@ -1160,7 +1141,7 @@ compare_values (tree val1, tree val2)
function. */
int
-value_inside_range (tree val, tree min, tree max)
+value_range_base::value_inside_range (tree val, tree min, tree max) const
{
int cmp1, cmp2;
@@ -1177,15 +1158,23 @@ value_inside_range (tree val, tree min, tree max)
return !cmp2;
}
-
-/* Return TRUE if *VR includes the value X. */
+/* Return TRUE if range contains VAL. */
bool
-range_includes_p (const value_range_base *vr, HOST_WIDE_INT x)
+value_range_base::contains_p (tree val) const
{
- if (vr->varying_p () || vr->undefined_p ())
+ if (varying_p ())
return true;
- return vr->may_contain_p (build_int_cst (vr->type (), x));
+
+ if (undefined_p ())
+ return false;
+
+ if (m_kind == VR_ANTI_RANGE)
+ {
+ int res = value_inside_range (val, min (), max ());
+ return res == 0 || res == -2;
+ }
+ return value_inside_range (val, min (), max ()) != 0;
}
/* Value range wrapper for wide_int_range_set_zero_nonzero_bits.
diff --git a/gcc/tree-vrp.h b/gcc/tree-vrp.h
index e48cc37bafc..3abe0f7fe98 100644
--- a/gcc/tree-vrp.h
+++ b/gcc/tree-vrp.h
@@ -70,7 +70,7 @@ public:
/* Misc methods. */
tree type () const;
- bool may_contain_p (tree) const;
+ bool contains_p (tree) const;
void set_and_canonicalize (enum value_range_kind, tree, tree);
bool zero_p () const;
bool nonzero_p () const;
@@ -97,6 +97,9 @@ protected:
friend void gt_ggc_mx (value_range_base *&);
friend void gt_pch_nx (value_range_base &);
friend void gt_pch_nx (value_range_base *, gt_pointer_operator, void *);
+
+private:
+ int value_inside_range (tree, tree, tree) const;
};
/* Note value_range cannot currently be used with GC memory, only
@@ -254,7 +257,6 @@ struct assert_info
extern void register_edge_assert_for (tree, edge, enum tree_code,
tree, tree, vec<assert_info> &);
extern bool stmt_interesting_for_vrp (gimple *);
-extern bool range_includes_p (const value_range_base *, HOST_WIDE_INT);
extern bool infer_value_range (gimple *, tree, tree_code *, tree *);
extern bool vrp_bitmap_equal_p (const_bitmap, const_bitmap);
@@ -267,7 +269,6 @@ extern int compare_values_warnv (tree, tree, bool *);
extern int operand_less_p (tree, tree);
extern bool vrp_val_is_min (const_tree);
extern bool vrp_val_is_max (const_tree);
-extern int value_inside_range (tree, tree, tree);
extern tree vrp_val_min (const_tree);
extern tree vrp_val_max (const_tree);
@@ -300,7 +301,11 @@ extern value_range_kind determine_value_range (tree, wide_int *, wide_int *);
inline bool
range_includes_zero_p (const value_range_base *vr)
{
- return range_includes_p (vr, 0);
+ /* ?? I'm not convinced we should return TRUE for undefined. */
+ /* Short-circuit these because they don't have a type. */
+ if (vr->undefined_p () || vr->varying_p ())
+ return true;
+ return vr->contains_p (build_zero_cst (vr->type ()));
}
#endif /* GCC_TREE_VRP_H */
diff --git a/gcc/vr-values.c b/gcc/vr-values.c
index 1c05ffb7f17..77b036a8ae6 100644
--- a/gcc/vr-values.c
+++ b/gcc/vr-values.c
@@ -1626,8 +1626,7 @@ compare_range_with_value (enum tree_code comp, value_range *vr, tree val,
|| comp == LE_EXPR)
return NULL_TREE;
- /* ~[VAL_1, VAL_2] OP VAL is known if VAL_1 <= VAL <= VAL_2. */
- if (value_inside_range (val, vr->min (), vr->max ()) == 1)
+ if (!vr->contains_p (val))
return (comp == NE_EXPR) ? boolean_true_node : boolean_false_node;
return NULL_TREE;