https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108601
--- Comment #15 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by hongtao Liu <liuho...@gcc.gnu.org>: https://gcc.gnu.org/g:209f02b0a9e9adc0bf0247cb5eef04e0f175d64e commit r13-5644-g209f02b0a9e9adc0bf0247cb5eef04e0f175d64e Author: liuhongt <hongtao....@intel.com> Date: Wed Feb 1 13:30:12 2023 +0800 Don't peel nonlinear iv(mult or shift) for epilog when vf is not constant. Normally when vf is not constant, it will be prevented by vectorizable_nonlinear_inductions, but for this case, it failed going into if (STMT_VINFO_RELEVANT_P (stmt_info)) { need_to_vectorize = true; if (STMT_VINFO_DEF_TYPE (stmt_info) == vect_induction_def && ! PURE_SLP_STMT (stmt_info)) ok = vectorizable_induction (loop_vinfo, stmt_info, NULL, NULL, &cost_vec); since the iv is never used outside of the loop, and will be dce later, so vectorizer doesn't bother checking if it's vectorizable. it's true but hit gcc_assert in vect_can_peel_nonlinear_iv_p when vf is not constant. One solution is ignoring the nonlinear iv peeling if it's !STMT_VINFO_RELEVANT_P (stmt_info) just like the upper code, the other solution is returning false earlier in the vect_can_peel_nonlinear_iv_p when vf is not constant, the patch chooses the second incase there's other cases using vect_can_advance_ivs_p which calls vect_can_peel_nonlinear_iv_p. Also remove vect_peel_nonlinear_iv_p from vectorizable_nonlinear_inductions. gcc/ChangeLog: PR tree-optimization/108601 * tree-vectorizer.h (vect_can_peel_nonlinear_iv_p): Removed. * tree-vect-loop.cc (vectorizable_nonlinear_induction): Remove vect_can_peel_nonlinear_iv_p. (vect_can_peel_nonlinear_iv_p): Don't peel nonlinear iv(mult or shift) for epilog when vf is not constant and moved the defination to .. * tree-vect-loop-manip.cc (vect_can_peel_nonlinear_iv_p): .. Here. gcc/testsuite/ChangeLog: * gcc.target/aarch64/pr108601.c: New test.
