[Bug target/117599] LoongArch support for BitInt

[yangyujie at loongson dot cn via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117599

--- Comment #12 from Yang Yujie <yangyujie at loongson dot cn> ---
Correction: The regression was caused by r16-3036-ga76a032354ee48. :P

Now I am running tests on this patch.  Will post if it's OK.