Interning can skip any inhabited ZST type in general.

Now refers to `wrapping_*`, not `checked_*` for wrapping intrinsics.

These parameters don't get modified.

Add codegen test for issue rust-lang#73827

Closes rust-lang#73827

…, r=oli-obk

Optimize const value interning for ZST types

Interning can skip any inhabited ZST type in general.

Fixes rust-lang#68010

r? @oli-obk

we can test std and core panic macros together

r? @oli-obk

Move orphan module-name/mod.rs files into module-name.rs files

Wrapping intrinsics doc links update.

The links in the wrapping intrinsics docs now refer to the `wrapping_*` functions, not the `checked_*` functions.

Add some MIR-related regression tests

Closes rust-lang#68841
Closes rust-lang#75053
Closes rust-lang#76375
Closes rust-lang#77911

I think they're fixed by rust-lang#77306.

Don't update `entries` in `TypedArena` if T does not need drop

As far as I can tell, `entries` is only used when dropping `TypedArenaChunk`s and their contents. It is already ignored there, if T is not `mem::needs_drop`, this PR just skips updating it's value.

You can see `TypedArenaChunk` ignoring the entry count in L71. The reasoning is similar to what you can find in `DroplessArena`.

r? @oli-obk

…ievink

Drop unneeded `mut`

These parameters don't get modified.

Note that `trailing_comment` is pub and gets exported from `rustc_ast_pretty`. Is that considered to be a stable API? If yes, and you want to reserve the right to modify `self` in `trailing_comment` in the future, that hunk would need to be dropped.

…r=jyn514

Remove unused type from librustdoc

r? @jyn514