https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106019
rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Assignee|unassigned at gcc dot gnu.org |rsandifo at gcc dot
gnu.org
Status|NEW |ASSIGNED
--- Comment #2 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org>
---
Created attachment 53172
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53172&action=edit
Candidate patch
Huh, yeah, surprising this has been present so long.
Running aff_combination_expand on off2 before the query in
(from dr_may_alias_p):
aff_tree off1, off2;
poly_widest_int size1, size2;
get_inner_reference_aff (DR_REF (a), &off1, &size1);
get_inner_reference_aff (DR_REF (b), &off2, &size2);
aff_combination_scale (&off1, -1);
aff_combination_add (&off2, &off1);
if (aff_comb_cannot_overlap_p (&off2, size1, size2))
return false;
seems to fix it, but I guess that then adds the burden of
maintaining the cache. Since we've already done similar
SSA_NAME expansion for DR_BASE_ADDRESS/DR_OFFSET, perhaps
we should just try to use that instead? The attached patch
does that and fixes the testcase.
But maybe there are cases that aff_combination_expand
would handle and this patch wouldn't -- not sure.
