Rollup of 8 pull requests
Successful merges:
- #67585 (Improve `char::is_ascii_*` codegen)
- #68914 (Speed up `SipHasher128`.)
- #68994 (rustbuild: include channel in sanitizers installed name)
- #69032 (ICE in nightly-2020-02-08: handle TerminatorKind::Yield in librustc_mir::transform::promote_consts::Validator method)
- #69034 (parser: Remove `Parser::prev_token_kind`)
- #69042 (Remove backtrace header text)
- #69059 (Remove a few unused objects)
- #69089 (Properly use the darwin archive format on Apple targets)
Failed merges:
r? @ghost
2d2be57097