Andrea Canciani 4e7aeaf1b5 Improve char::is_ascii_* code
These methods explicitly check if a char is in a specific ASCII range,
therefore the `is_ascii()` check is not needed, but LLVM seems to be
unable to remove it.

WARNING: this change improves the performance on ASCII `char`s, but
complex checks such as `is_ascii_punctuation` become slower on
non-ASCII `char`s.
2020-02-11 10:22:47 +01:00
..
2020-02-11 10:22:47 +01:00