Split up attribute parsing code and move data types to rustc_attr_data_structures

[jdonszelmann]

This change renames rustc_attr to rustc_attr_parsing, and splits up the parsing code. At the same time, all the data types used move to rustc_attr_data_structures. This is in preparation of also having a third crate: rustc_attr_validation

I initially envisioned this as two separate PRs, but I think doing it in one go reduces the number of ways others would have to rebase their changes on this. However, I can still split them.

r? @oli-obk (we already discussed how this is a first step in a larger plan)

For a more detailed plan on how attributes are going to change, see #131229

Edit: this looks like a giant PR, but the changes are actually rather trivial. Each commit is reviewable on its own, and mostly moves code around. No new logic is added.

[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

Some changes occurred to the CTFE machinery

cc @rust-lang/wg-const-eval

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

The Miri subtree was changed

cc @rust-lang/miri

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

Some changes occurred in compiler/rustc_codegen_gcc

cc @antoyo, @GuillaumeGomez

[jdonszelmann]

@rustbot label +A-attributes

For the rustdoc changes, I only made that code depend on rustc_attr_parsing instead of rustc_attr. No actual logic changed.

[jdonszelmann]

well, my last rebase had no conflicts, but clearly it didn't work very well anyway... 1s

[oli-obk]

accidentally committed a test file

[oli-obk]

(even though it was removed in the second commit)

[jdonszelmann]

oops, yea I had noticed but should've removed it from the first one haha

[oli-obk]

I reviewed some changes and the overall change. I'm just gonna assume all the individual parts have been moved correctly (as no tests have been touched, and the downstream usages are all just import changes, this appears so)

@bors delegate+

r=me with the nit for a clean history

[bors]

✌️ @jdonszelmann, you can now approve this pull request!

If @oli-obk told you to "r=me" after making some further change, please make that change, then do @bors r=@oli-obk

[jdonszelmann]

@bors r=@oli-obk

[bors]

📌 Commit efb98b6 has been approved by oli-obk

It is now in the queue for this repository.

[jieyouxu]

@bors p=6 (conflict-prone)

[jieyouxu]

(conflict-check)

[jieyouxu]

@bors r=@oli-obk

[bors]

📌 Commit efb98b6 has been approved by oli-obk

It is now in the queue for this repository.