https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93781
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Andrew Macleod <amacl...@gcc.gnu.org>: https://gcc.gnu.org/g:d0d8b5d83614d8f0d0e40c0520d4f40ffa01f8d9 commit r11-5185-gd0d8b5d83614d8f0d0e40c0520d4f40ffa01f8d9 Author: Andrew MacLeod <amacl...@redhat.com> Date: Thu Nov 19 17:41:30 2020 -0500 Process only valid shift ranges. When shifting outside the valid range of [0, precision-1], we can choose to process just the valid ones since the rest is undefined. this allows us to produce results for x << [0,2][+INF, +INF] by discarding the invalid ranges and processing just [0,2]. gcc/ PR tree-optimization/93781 * range-op.cc (get_shift_range): Rename from undefined_shift_range_check and now return valid shift ranges. (operator_lshift::fold_range): Use result from get_shift_range. (operator_rshift::fold_range): Ditto. gcc/testsuite/ * gcc.dg/tree-ssa/pr93781-1.c: New. * gcc.dg/tree-ssa/pr93781-2.c: New. * gcc.dg/tree-ssa/pr93781-3.c: New.
