Will adjust, re-test and commit. Thanks. Aldy
On Tue, Nov 30, 2021 at 10:00 AM Richard Biener <richard.guent...@gmail.com> wrote: > > On Tue, Nov 30, 2021 at 9:51 AM Aldy Hernandez <al...@redhat.com> wrote: > > > > On Tue, Nov 30, 2021 at 8:37 AM Richard Biener > > <richard.guent...@gmail.com> wrote: > > > > > > On Mon, Nov 29, 2021 at 4:24 PM Aldy Hernandez <al...@redhat.com> wrote: > > > > > > > > On Mon, Nov 29, 2021 at 3:48 PM Richard Biener > > > > <richard.guent...@gmail.com> wrote: > > > > > > > > > > On Mon, Nov 29, 2021 at 3:39 PM Jeff Law <jeffreya...@gmail.com> > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > On 11/29/2021 7:00 AM, Aldy Hernandez via Gcc-patches wrote: > > > > > > > As discussed in the PR. The code makes no difference, so > > > > > > > whatever test > > > > > > > we added this special case for has been fixed or is being papered > > > > > > > over. > > > > > > > I think we should fix any fall out upstream. > > > > > > > > > > > > > > [Unless Andrew can remember why we added this and it still > > > > > > > applies.] > > > > > > > > > > > > > > Tested on x86-64 Linux. > > > > > > > > > > > > > > OK for trunk? > > > > > > > > > > > > > > PR 103451 > > > > > > > > > > > > > > gcc/ChangeLog: > > > > > > > > > > > > > > * range-op.cc (operator_div::wi_fold): Remove > > > > > > > can_throw_non_call_exceptions special case. > > > > > > > > > > > > > > gcc/testsuite/ChangeLog: > > > > > > > > > > > > > > * gcc.dg/pr103451.c: New test. > > > > > > I'll defer to Andrew, but it seems wrong to me. The whole point is > > > > > > to > > > > > > set the result to varying so that we don't know the result and never > > > > > > remove the division which is critical for -fnon-call-exceptions. > > > > > > > > > > But that has nothing to do with computing the value range for > > > > > the result which is only accessible when the stmt does _not_ throw ... > > > > > > > > > > That is, if we compute non-VARYING here and because of that > > > > > remove the stmt then _that's_ the place to fix (IMO) > > > > > > > > Ughh, I think you're both right. > > > > > > > > We should fix this upstream AND we should test for the presence of the > > > > division by 0 in the optimized dump. > > > > > > > > Of course doing both opens a can of worms. The division by zero can > > > > be cleaned up by (at least) DCE, DSE, and the code sinking passes. > > > > I've fixed all 3 in the attached (untested) patch. Dunno what y'all > > > > want to do at this point. > > > > > > I think you need to add -fno-delete-dead-exceptions to the testcase. > > > The sinking > > > bug looks real, but just > > > > > > && (cfun->can_delete_dead_exceptions > > > || !stmt_could_throw_p (cfun, stmt)) > > > > > > is needed there. That change is OK. > > > > Did you mean the entire patch (as attached) is OK, or just the sink part? > > The DCE and DSE parts are wrong and not needed. The remaining pieces > are OK. > > Thanks, > Richard. > > > Thanks. > > Aldy >
