https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93582
--- Comment #40 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:fe19699ae2883b252d30f98481d32dabff00744b commit r10-7035-gfe19699ae2883b252d30f98481d32dabff00744b Author: Jakub Jelinek <ja...@redhat.com> Date: Thu Mar 5 08:00:04 2020 +0100 sccvn: Fix handling of POINTER_PLUS_EXPR in memset offset [PR93582] > > where POINTER_PLUS_EXPR last operand has sizetype type, thus unsigned, > > and in the testcase gimple_assign_rhs2 (def) is thus 0xf000000000000001ULL > > which multiplied by 8 doesn't fit into signed HWI. If it would be treated > > as signed offset instead, it would fit (-0xfffffffffffffffLL, multiplied > > by 8 is -0x7ffffffffffffff8LL). Unfortunately with the poly_int obfuscation > > I'm not sure how to convert it from unsigned to signed poly_int. > > mem_ref_offset provides a boiler-plate for this: > > poly_offset_int::from (wi::to_poly_wide (TREE_OPERAND (t, 1)), SIGNED); Thanks, that seems to work. The test now works on both big-endian and little-endian. 2020-03-05 Richard Biener <rguent...@suse.de> Jakub Jelinek <ja...@redhat.com> PR tree-optimization/93582 * tree-ssa-sccvn.c (vn_reference_lookup_3): Treat POINTER_PLUS_EXPR last operand as signed when looking for memset offset. Formatting fix. * gcc.dg/tree-ssa/pr93582-11.c: New test. Co-authored-by: Richard Biener <rguent...@suse.de>
