Auto merge of #49321 - ishitatsuyuki:compile-pass, r=alexcrichton
Introduce compile-pass
r? @alexcrichton
The plan is to move things that cannot fail (no assert, unwrap, etc) out so we don't have to run them, and in the long term we can also stop running LLVM for them.
Out of 3215 tests...
```
Language Files Lines Code Comments Blanks
Rust 3215 119254 64688 35135 19431
```
16% of them has an empty main (which is already moved in this PR).
```
grep -rnPzl 'fn main\(\)\s*{\s*}' | xargs rg --files-without-match cfg | wc -l
547
```
And only 50% of the tests contains assertions:
```
rg -e assert -e unwrap -e expect -e panic -l | wc -l
1600
```
The remainder is likely able to get moved, but they need check by a human so I didn't touch them in PR.
cc @rust-lang/compiler
* [ ] Update documentation