Rollup of 3 perf-sensitive pull requests - #164285

Rollup of 3 perf-sensitive pull requests#164285

rust-bors[bot] merged 22 commits into

rust-lang:mainrust-lang/rust:mainfrom

JonathanBrouwer:rollup-kX2T7LSJonathanBrouwer/rust:rollup-kX2T7LSCopy head branch name to clipboard