https://www.reddit.com/r/programming/comments/8js69n/validating_utf8_strings_using_as_little_as_07/
D doesn't seem to have C definitions for the x86 SIMD intrinsics, which is a bummer
https://issues.dlang.org/show_bug.cgi?id=18865 It's too bad that nothing came of std.simd.
