| Message ID | 1449685589-10628-2-git-send-email-s.pop@samsung.com |
|---|---|
| State | New |
| Headers | show |
On 09/12/15 19:26, Sebastian Pop wrote: > we used to add the access functions in the wrong order, Fortran style, leading to unprofitable interchanges. > --- > gcc/graphite-sese-to-poly.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/gcc/graphite-sese-to-poly.c b/gcc/graphite-sese-to-poly.c > index 887c212..480c552 100644 > --- a/gcc/graphite-sese-to-poly.c > +++ b/gcc/graphite-sese-to-poly.c > @@ -912,7 +912,7 @@ pdr_add_memory_accesses (isl_map *acc, dr_info &dri) > for (i = 0; i < nb_subscripts; i++) > { > isl_pw_aff *aff; > - tree afn = DR_ACCESS_FN (dr, nb_subscripts - 1 - i); > + tree afn = DR_ACCESS_FN (dr, i); > > aff = extract_affine (scop, afn, > isl_space_domain (isl_map_get_space (acc))); > Hi, I think the fix for PR68953 ( https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=234851 ) undoes this fix. What problem was this patch intending to address? In other words, have I re-introduced a problem by fixing PR68953 ? Thanks, - Tom
On Sat, Apr 9, 2016 at 11:00 AM, Tom de Vries <Tom_deVries@mentor.com> wrote: > On 09/12/15 19:26, Sebastian Pop wrote: >> >> we used to add the access functions in the wrong order, Fortran style, >> leading to unprofitable interchanges. >> --- >> gcc/graphite-sese-to-poly.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/gcc/graphite-sese-to-poly.c b/gcc/graphite-sese-to-poly.c >> index 887c212..480c552 100644 >> --- a/gcc/graphite-sese-to-poly.c >> +++ b/gcc/graphite-sese-to-poly.c >> @@ -912,7 +912,7 @@ pdr_add_memory_accesses (isl_map *acc, dr_info &dri) >> for (i = 0; i < nb_subscripts; i++) >> { >> isl_pw_aff *aff; >> - tree afn = DR_ACCESS_FN (dr, nb_subscripts - 1 - i); >> + tree afn = DR_ACCESS_FN (dr, i); >> >> aff = extract_affine (scop, afn, >> isl_space_domain (isl_map_get_space (acc))); >> > > Hi, > > I think the fix for PR68953 ( > https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=234851 ) undoes this > fix. > > What problem was this patch intending to address? > > In other words, have I re-introduced a problem by fixing PR68953 ? > From the commit message of r234851, it was an interchange profitability that triggered the change. I think there is still a problem in the way we are parsing arrays in C vs. Fortran. It is good that now we have the correctness testcase that you added with the patch. Thanks, Sebastian
diff --git a/gcc/graphite-sese-to-poly.c b/gcc/graphite-sese-to-poly.c index 887c212..480c552 100644 --- a/gcc/graphite-sese-to-poly.c +++ b/gcc/graphite-sese-to-poly.c @@ -912,7 +912,7 @@ pdr_add_memory_accesses (isl_map *acc, dr_info &dri) for (i = 0; i < nb_subscripts; i++) { isl_pw_aff *aff; - tree afn = DR_ACCESS_FN (dr, nb_subscripts - 1 - i); + tree afn = DR_ACCESS_FN (dr, i); aff = extract_affine (scop, afn, isl_space_domain (isl_map_get_space (acc)));