https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109971
--- Comment #2 from JuzheZhong <juzhe.zhong at rivai dot ai> --- It seems this condition: + /* If we're vectorizing a loop that uses length "controls" and + can iterate more than once, we apply decrementing IV approach + in loop control. */ + if (LOOP_VINFO_CAN_USE_PARTIAL_VECTORS_P (loop_vinfo) + && !LOOP_VINFO_LENS (loop_vinfo).is_empty () + && LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo) == 0 + && !(LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo) + && known_le (LOOP_VINFO_INT_NITERS (loop_vinfo), + LOOP_VINFO_VECT_FACTOR (loop_vinfo)))) + LOOP_VINFO_USING_DECREMENTING_IV_P (loop_vinfo) = true; dit not disable decrement IV in powerPC. Sorry for creating this issue since I only tested on X86. Should I add target hook for decrement IV? I am waiting for Richard's comments.
