https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59461
--- Comment #7 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- > There is a reasonable chance that this patch broke mips64 n64 but I do not > have confirmation yet. See PR target/78660. The quoted hunk only reverted a recent pessimization (r205550), the current code is the correct approach as explained in the comment. > I can vaguely see how this patch may affect MIPS64 in terms of how 32-bit > values are handled on a MIPS64 architecture with the sign bit replicated to > the upper-32 bits. This presumably is somehow not accounted for in the > nonzero_bits logic. Probably yes, maybe in conjunction with WORD_REGISTER_OPERATIONS. > I'm yet to get my head around what the issue is but if anyone has a pointer > based on the potential impact on MIPS64 as described above then I'd be > grateful. Is WORD_REGISTER_OPERATIONS correct for MIPS64, i.e. do all instructions operate on the full 64-bit itneger registers?
