Backports VRP fixes from the D front-end implementation to the C++ port,
and fixes errors reported by ubsan build where the conversion from D
didn't include adjusting integer suffixes from 'UL' to 'ULL'.

Fixes https://gcc.gnu.org/PR88366

Reviewed-on: https://github.com/dlang/dmd/pull/9046

From-SVN: r266925