Kenneth Zadeck <zad...@naturalbridge.com> writes: >> Changing the representation of unsigned constants is only worthwhile >> if we can avoid the force_to_size for some unsigned cases. I think we can >> avoid it for precision >= xprecision && !small_prec. Either we should take >> the hit of doing that comparison (but see below) or the change isn't >> worthwhile. > i think that it is something closer to precision >= xprecision + > HOST_BITS_PER_WIDE_INT && ... > The problem is that the tree cst may have one extra block beyond the > precision.
Ah, OK. >> I was thinking that we should always be able to use the constant as-is >> for max_wide_int-based and addr_wide_int-based operations. The small_prec > again, you can get edge cased to death here. i think it would work > for max because that really is bigger than anything else, but it is > possible (though unlikely) to have something big converted to an address > by truncation. But I'd have expected that conversion to be represented by an explicit CONVERT_EXPR or NOP_EXPR. It seems wrong to use addr_wide_int directly on something that isn't bit- or byte-address-sized. It'd be the C equivalent of int + long -> int rather than the expected int + long -> long. Same goes for wide_int. If we're doing arithmetic at a specific precision, it seems odd for one of the inputs to be wider and yet not have an explicit truncation. Thanks, Richard
