https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102124
--- Comment #4 from Tomas Chang <changyp6 at gmail dot com> --- (In reply to Jakub Jelinek from comment #3) > Before vectorization the loop body is: > _1 = a_19(D) + i_29; > _2 = *_1; > _3 = (int) _2; > _4 = b_20(D) + i_29; > _5 = *_4; > _6 = (int) _5; > _7 = _3 - _6; > ab_21 = _7 | ab_25; > _10 = _6 - _3; > ba_22 = _10 | ba_27; > where _2 and _5 are unsigned char and _3, _6, _7, _10 are int. > It is vectorized as > vect_patt_54.17_61 = WIDEN_MINUS_LO_EXPR <vect__2.13_56, vect__5.16_17>; > vect_patt_54.17_62 = WIDEN_MINUS_HI_EXPR <vect__2.13_56, vect__5.16_17>; > vect_patt_53.18_63 = [vec_unpack_lo_expr] vect_patt_54.17_61; > vect_patt_53.18_64 = [vec_unpack_hi_expr] vect_patt_54.17_61; > vect_patt_53.18_65 = [vec_unpack_lo_expr] vect_patt_54.17_62; > vect_patt_53.18_66 = [vec_unpack_hi_expr] vect_patt_54.17_62; > _7 = _3 - _6; > vect_ab_21.19_67 = vect_patt_53.18_63 | vect_ab_25.9_13; > vect_ab_21.19_68 = vect_patt_53.18_64 | vect_ab_21.19_67; > vect_ab_21.19_69 = vect_patt_53.18_65 | vect_ab_21.19_68; > vect_ab_21.19_70 = vect_patt_53.18_66 | vect_ab_21.19_69; > ab_21 = _7 | ab_25; > which means it is vectorized as if it was instead of (int) _2 - (int) _6 > (int) (unsigned short) ((unsigned short) _2 - (unsigned short) _6). Thank you very much for confirming this issue so quicky! Hope this issue can be fixed soon!
