Handle GlobalCtxt directly from librustc_interface query system
This PR constructs the `GlobalCtxt` as a member of the `Queries` in librustc_interface.
This simplifies the code to construct it, at the expense of added complexity in the query control flow.
This allows to handle the arenas directly from librustc_interface.
Based on #66707
r? @Zoxc
The construction of the GlobalCtxt is moved from a generator's stack to
the Queries struct. Since the GlobalCtxt requires the HIR Forest and the
arenas to live longer, those are moved into Queries the same way.
The resulting handling of objects is more brittle, because consumers of
the Once objects need to be careful of their initialisation.
Remove pretty printing of specific nodes in AST
The ability to print a specific item as identified by NodeId or path
seems not particularly useful, and certainly carries quite a bit of
complexity with it.
This is intended to simplify our CLI parsing a bit and remove a
non-uncomplicated piece of it; I largely did this to remove the
dependency on NodeId from librustc/session but it's not really
necessary to do so in this invasive a way. The alternative is
moving it to librustc_interface or driver, probably.
Move process_configure_mod to rustc_parse
This removes the hack in favor of perhaps a less principled, but less painful, approach.
This also supports my work to decouple `Session` from librustc, as `ParseSess` currently has `Attribute` as "part" of it but after this PR will no longer do so.
The ability to print a specific item as identified by NodeId or path
seems not particularly useful, and certainly carries quite a bit of
complexity with it.
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.
