This PR reverts #29543 and instead implements proper support for "=*m" and "+*m" indirect output operands. This provides a framework on top of which support for plain memory operands ("m", "=m" and "+m") can be implemented.
This also fixes the liveness analysis pass not handling read/write operands correctly.
Instead of `ast::Ident`, bindings, paths and labels in HIR now keep a new structure called `hir::Ident` containing mtwt-renamed `name` and the original not-renamed `unhygienic_name`. `name` is supposed to be used by default, `unhygienic_name` is rarely used.
This is not ideal, but better than the status quo for two reasons:
- MTWT tables can be cleared immediately after lowering to HIR
- This is less bug-prone, because it is impossible now to forget applying `mtwt::resolve` to a name. It is still possible to use `name` instead of `unhygienic_name` by mistake, but `unhygienic_name`s are used only in few very special circumstances, so it shouldn't be a problem.
Besides name resolution `unhygienic_name` is used in some lints and debuginfo. `unhygienic_name` can be very well approximated by "reverse renaming" `token::intern(name.as_str())` or even plain string `name.as_str()`, except that it would break gensyms like `iter` in desugared `for` loops. This approximation is likely good enough for lints and debuginfo, but not for name resolution, unfortunately (see https://github.com/rust-lang/rust/issues/27639), so `unhygienic_name` has to be kept.
cc https://github.com/rust-lang/rust/issues/29782
r? @nrc
nodes in statement position.
Extended #[cfg] folder to allow removal of statements, and
of expressions in optional positions like expression lists and trailing
block expressions.
Extended lint checker to recognize lint levels on expressions and
locals.
rather being stored inline. Refactor (and rename) the visitor so that
(by default) it only visits the interior content of an item not nested
items.
This is a [breaking-change] for anyone who uses the HIR visitor. Besides
changing `visit::` to `intravisit::`, you need to refactor your visitor
in one of two ways, depending on what it requires:
1. If you just want to visit all items (most common), you should call
`krate.visit_all_items(&mut visitor)`.
2. If you need to visit nested items in the middle of the parent items,
you should override `visit_nested_item` with something like:
`self.visit_item(self.tcx.map.expect_item(item.id))`, presuming you
have access to a tcx (or at least a HIR map).
[breaking change]
I'm not sure if those renames are ok. [TokenType::Tt* to TokenType::*](https://github.com/rust-lang/rust/pull/29582) was obvious, but for all those Item-enums it's less obvious to me what the right way forward is due to the underscore.
The public set is expanded with trait items, impls and their items, foreign items, exported macros, variant fields, i.e. all the missing parts. Now it's a subset of the exported set.
This is needed for https://github.com/rust-lang/rust/pull/29083 because stability annotation pass uses the public set and all things listed above need to be annotated.
Rustdoc can now be migrated to the public set as well, I guess.
Exported set is now slightly more correct with regard to exported items in blocks - 1) blocks in foreign items are considered and 2) publicity is not inherited from the block's parent - if a function is public it doesn't mean structures defined in its body are public.
r? @alexcrichton or maybe someone else
This PR removes random remaining `Ident`s outside of libsyntax and performs general cleanup
In particular, interfaces of `Name` and `Ident` are tidied up, `Name`s and `Ident`s being small `Copy` aggregates are always passed to functions by value, and `Ident`s are never used as keys in maps, because `Ident` comparisons are tricky.
Although this PR closes https://github.com/rust-lang/rust/issues/6993 there's still work related to it:
- `Name` can be made `NonZero` to compress numerous `Option<Name>`s and `Option<Ident>`s but it requires const unsafe functions.
- Implementation of `PartialEq` on `Ident` should be eliminated and replaced with explicit hygienic, non-hygienic or member-wise comparisons.
- Finally, large parts of AST can potentially be converted to `Name`s in the same way as HIR to clearly separate identifiers used in hygienic and non-hygienic contexts.
r? @nrc
Make sure Name, SyntaxContext and Ident are passed by value
Make sure Idents don't serve as keys (or parts of keys) in maps, Ident comparison is not well defined
