https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113831
--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <rgue...@gcc.gnu.org>: https://gcc.gnu.org/g:938a419182f8c43bd1212ffb98f8aa6077cf8326 commit r14-8929-g938a419182f8c43bd1212ffb98f8aa6077cf8326 Author: Richard Biener <rguent...@suse.de> Date: Fri Feb 9 10:16:38 2024 +0100 tree-optimization/113831 - wrong VN with structurally identical ref When we use get_ref_base_and_extent during VN and that ends up using global ranges to restrict the range of a ref we have to take care of not using the same expression in the hashtable as for a ref that could not use that global range. The following attempts to ensure this by applying similar logic as get_ref_base_and_extent to copy_reference_ops_from_ref so they behave consistent. PR tree-optimization/113831 PR tree-optimization/108355 * tree-ssa-sccvn.cc (copy_reference_ops_from_ref): When we see variable array indices and get_ref_base_and_extent can resolve those to constants fix up the ops to constants as well. (ao_ref_init_from_vn_reference): Use 'off' member for ARRAY_REF and ARRAY_RANGE_REF instead of recomputing it. (valueize_refs_1): Also fixup 'off' of ARRAY_RANGE_REF. * gcc.dg/torture/pr113831.c: New testcase. * gcc.dg/tree-ssa/ssa-fre-104.c: Likewise.