The function move_by_pieces in expr.c enters to endless loop when the backend defines the sizes of all data types to be the same size (aka CHAR_TYPE_SIZE = SHORT_TYPE_SIZE = INT_TYPE_SIZE = anyvalue …). The loop itself occurs in this code section - while (max_size > 1) { for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode; tmode = GET_MODE_WIDER_MODE (tmode)) if (GET_MODE_SIZE (tmode) < max_size) mode = tmode; if (mode == VOIDmode) break; icode = mov_optab->handlers[(int) mode].insn_code; if (icode != CODE_FOR_nothing && align >= GET_MODE_ALIGNMENT (mode)) move_by_pieces_1 (GEN_FCN (icode), mode, &data); max_size = GET_MODE_SIZE (mode); } The idea here is to decrease the sizes of copying insn, or something like that, But what if it isn’t decreasing? Thanks.
Created attachment 23422 [details] Fixes problem (resubmit, lost due to collision)
(In reply to comment #1) > Created attachment 23422 [details] > Fixes problem (resubmit, lost due to collision) Sorry, bugzilla confused me, this attachment was intended for 42722.
>CHAR_TYPE_SIZE = SHORT_TYPE_SIZE = INT_TYPE_SIZE Won't matter in this loop. what matters is QImode == 1. But if the target overrides machmode.def I doubt this can happen INT_MODE (QI, 1); INT_MODE (HI, 2); INT_MODE (SI, 4); INT_MODE (DI, 8); INT_MODE (TI, 16);