Move `DIAGNOSTICS` usage to `rustc_driver`
Remove `rustc_interface`'s dependency on `rustc_error_codes` and centralize all usages of `DIAGNOSTICS` in `rustc_driver`. Once we remove all references to `rustc_error_codes` in all other crates but `rustc_driver`, this should allow for incremental recompilation of the compiler to be smoother when tweaking error codes. This works towards https://github.com/rust-lang/rust/issues/66210#issuecomment-551862528.
(May include traces of minor drive-by cleanup.)
r? @Mark-Simulacrum
Move self-profile infrastructure to data structures
The single dependency on queries (QueryName) can be fairly easily
abstracted via a trait and this further decouples Session from librustc
(the primary goal).
This is intended as a precursor to moving Session out of librustc, but since that involves lots of smaller steps that move around code I'm splitting it up into separate PRs.
Split libsyntax apart
In this PR the general idea is to separate the AST, parser, and friends by a more data / logic structure (tho not fully realized!) by separating out the parser and macro expansion code from libsyntax. Specifically have now three crates instead of one (libsyntax):
- libsyntax:
- concrete syntax tree (`syntax::ast`)
- definition of tokens and token-streams (`syntax::{token, tokenstream}`) -- used by `syntax::ast`
- visitors (`syntax::visit`, `syntax::mut_visit`)
- shared definitions between `libsyntax_expand`
- feature gating (`syntax::feature_gate`) -- we could possibly move this out to its own crater later.
- attribute and meta item utilities, including used-marking (`syntax::attr`)
- pretty printer (`syntax::print`) -- this should possibly be moved out later. For now I've reduced down the dependencies to a single essential one which could be broken via `ParseSess`. This entails that e.g. `Debug` impls for `Path` cannot reference the pretty printer.
- definition of `ParseSess` (`syntax::sess`) -- this is used by `syntax::{attr, print, feature_gate}` and is a common definition used by the parser and other things like librustc.
- the `syntax::source_map` -- this includes definitions used by `syntax::ast` and other things but could ostensibly be moved `syntax_pos` since that is more related to this module.
- a smattering of misc utilities not sufficiently important to itemize -- some of these could be moved to where they are used (often a single place) but I wanted to limit the scope of this PR.
- librustc_parse:
- parser (`rustc_parse::parser`) -- reading a file and such are defined in the crate root tho.
- lexer (`rustc_parse::lexer`)
- validation of meta grammar (post-expansion) in (`rustc_parse::validate_attr`)
- libsyntax_expand -- this defines the infra for macro expansion and conditional compilation but this is not libsyntax_ext; we might want to merge them later but currently libsyntax_expand is depended on by librustc_metadata which libsyntax_ext is not.
- conditional compilation (`syntax_expand::config`) -- moved from `syntax::config` to here
- the bulk of this crate is made up of the old `syntax::ext`
r? @estebank
We also sever syntax's dependency on rustc_target as a result.
This should slightly improve pipe-lining.
Moreover, some cleanup is done in related code.
Lockless LintStore
This removes mutability from the lint store after registration. Each commit stands alone, for the most part, though they don't make sense out of sequence.
The intent here is to move LintStore to a more parallel-friendly architecture, although also just a cleaner one from an implementation perspective. Specifically, this has the following changes:
* We no longer implicitly register lints when registering lint passes
* For the most part this means that registration calls now likely want to call something like:
`lint_store.register_lints(&Pass::get_lints())` as well as `register_*_pass`.
* In theory this is a simplification as it's much easier for folks to just register lints and then have passes that implement whichever lint however they want, rather than necessarily tying passes to lints.
* Lint passes still have a list of associated lints, but a followup PR could plausibly change that
* This list must be known for a given pass type, not instance, i.e., `fn get_lints()` is the signature instead of `fn get_lints(&self)` as before.
* We do not store pass objects, instead storing constructor functions. This means we always get new passes when running lints (this happens approximately once though for a given compiler session, so no behavior change is expected).
* Registration API is _much_ simpler: generally all functions are just taking `Fn() -> PassObject` rather than several different `bool`s.
Move to using Box<dyn Fn() -> ...> so that we can let plugins register
state.
This also adds a callback that'll get called from plugin registration so
that Clippy and other tools can register lints without using the plugin
API. The plugin API still works, but this new API is more compatible
with drivers other than rustc.
Access through tcx is fine -- by that point, the lint store is frozen,
but direct access through Session will go away in future commits, as
lint store is still mutable in early stages of Session, and will be
removed completely.
Several changes to the codegen backend organization
* Split functions from values in cg_ssa `BackendTypes`.
* Remove `is_const_integral` function from `ConstMethods`.
* Actually register the invalid monomorphization of intrinsic long diagnostic and remove the `diagnostics` method from `CodegenBackends`, as it was unused.
* Add cg_ssa and cg_utils provided methods to `default_provide`, so codegen backend don't have to do it themself.