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@ -26,7 +26,7 @@
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- [Part 2: How rustc works](./part-2-intro.md)
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- [High-level overview of the compiler source](./high-level-overview.md)
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- [The Rustc Driver](./rustc-driver.md)
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- [The Rustc Driver and Interface](./rustc-driver.md)
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- [Rustdoc](./rustdoc.md)
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- [Queries: demand-driven compilation](./query.md)
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- [The Query Evaluation Model in Detail](./queries/query-evaluation-model-in-detail.md)
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@ -7,7 +7,7 @@ compiler.
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Item | Kind | Short description | Chapter | Declaration
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----------------|----------|-----------------------------|--------------------|-------------------
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`BodyId` | struct | One of four types of HIR node identifiers | [Identifiers in the HIR] | [src/librustc/hir/mod.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/hir/struct.BodyId.html)
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`CompileState` | struct | State that is passed to a callback at each compiler pass | [The Rustc Driver] | [src/librustc_driver/driver.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/driver/struct.CompileState.html)
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`Compiler` | struct | Represents a compiler session and can be used to drive a compilation. | [The Rustc Driver and Interface] | [src/librustc_interface/interface.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/interface/struct.Compiler.html)
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`ast::Crate` | struct | A syntax-level representation of a parsed crate | [The parser] | [src/librustc/hir/mod.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ast/struct.Crate.html)
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`hir::Crate` | struct | A more abstract, compiler-friendly form of a crate's AST | [The Hir] | [src/librustc/hir/mod.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/hir/struct.Crate.html)
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`DefId` | struct | One of four types of HIR node identifiers | [Identifiers in the HIR] | [src/librustc/hir/def_id.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/hir/def_id/struct.DefId.html)
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@ -18,8 +18,9 @@ Item | Kind | Short description | Chapter |
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`P` | struct | An owned immutable smart pointer. By contrast, `&T` is not owned, and `Box<T>` is not immutable. | None | [src/syntax/ptr.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ptr/struct.P.html)
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`ParamEnv` | struct | Information about generic parameters or `Self`, useful for working with associated or generic items | [Parameter Environment] | [src/librustc/ty/mod.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/ty/struct.ParamEnv.html)
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`ParseSess` | struct | This struct contains information about a parsing session | [The parser] | [src/libsyntax/parse/mod.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/parse/struct.ParseSess.html)
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`Query` | struct | Represents the result of query to the `Compiler` interface and allows stealing, borrowing, and returning the results of compiler passes. | [The Rustc Driver and Interface] | [src/librustc_interface/queries.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/queries/struct.Query.html)
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`Rib` | struct | Represents a single scope of names | [Name resolution] | [src/librustc_resolve/lib.rs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_resolve/struct.Rib.html)
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`Session` | struct | The data associated with a compilation session | [The parser], [The Rustc Driver] | [src/librustc/session/mod.html](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/session/struct.Session.html)
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`Session` | struct | The data associated with a compilation session | [The parser], [The Rustc Driver and Interface] | [src/librustc/session/mod.html](https://doc.rust-lang.org/nightly/nightly-rustc/rustc/session/struct.Session.html)
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`SourceFile` | struct | Part of the `SourceMap`. Maps AST nodes to their source code for a single source file. Was previously called FileMap | [The parser] | [src/libsyntax_pos/lib.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.SourceFile.html)
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`SourceMap` | struct | Maps AST nodes to their source code. It is composed of `SourceFile`s. Was previously called CodeMap | [The parser] | [src/libsyntax/source_map.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.SourceMap.html)
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`Span` | struct | A location in the user's source code, used for error reporting primarily | [Emitting Diagnostics] | [src/libsyntax_pos/span_encoding.rs](https://doc.rust-lang.org/nightly/nightly-rustc/syntax_pos/struct.Span.html)
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@ -33,7 +34,7 @@ Item | Kind | Short description | Chapter |
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[The HIR]: ../hir.html
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[Identifiers in the HIR]: ../hir.html#hir-id
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[The parser]: ../the-parser.html
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[The Rustc Driver]: ../rustc-driver.html
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[The Rustc Driver and Interface]: ../rustc-driver.html
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[Type checking]: ../type-checking.html
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[The `ty` modules]: ../ty.html
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[Rustdoc]: ../rustdoc.html
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@ -1,9 +1,14 @@
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# Appendix A: A tutorial on creating a drop-in replacement for rustc
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> **Note:** This is a copy of `@nrc`'s amazing [stupid-stats]. You should find
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> a copy of the code on the GitHub repository although due to the compiler's
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> constantly evolving nature, there is no guarantee it'll compile on the first
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> go.
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> a copy of the code on the GitHub repository.
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>
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> Due to the compiler's constantly evolving nature, the `rustc_driver`
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> mechanisms described in this chapter have changed. In particular, the
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> `CompilerCalls` and `CompileController` types have been replaced by
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> [`Callbacks`][cb]. Also, there is a new query-based interface in the
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> [`rustc_interface`] crate. See [The Rustc Driver and Interface] for more
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> information.
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Many tools benefit from being a drop-in replacement for a compiler. By this, I
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mean that any user of the tool can use `mytool` in all the ways they would
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@ -92,7 +97,7 @@ translation).
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> and [`librustc_codegen_utils`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_utils/index.html).
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All these phases are coordinated by the driver. To see the exact sequence, look
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at [the `compile_input` function in `librustc_driver`][compile-input].
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at the `compile_input` function in `librustc_driver`.
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The driver handles all the highest level coordination of compilation -
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1. handling command-line arguments
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2. maintaining compilation state (primarily in the `Session`)
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@ -101,9 +106,6 @@ The driver handles all the highest level coordination of compilation -
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To create a drop-in compiler replacement or a compiler replacement,
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we leave most of compilation alone and customise the driver using its APIs.
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[compile-input]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/driver/fn.compile_input.html
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## The driver customisation APIs
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There are two primary ways to customise compilation - high level control of the
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@ -409,4 +411,7 @@ analysis, rather than doing its own analysis). Other parts of the compiler
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internally (I already changed save-analysis to use `CompilerController`). I've
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been experimenting with a prototype rustfmt which also uses these APIs.
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[cb]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/trait.Callbacks.html
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[stupid-stats]: https://github.com/nrc/stupid-stats
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[`rustc_interface`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/index.html
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[The Rustc Driver and Interface]: ../rustc-driver.html
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@ -1,46 +1,32 @@
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# The Rustc Driver
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# The Rustc Driver and Interface
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The [`rustc_driver`] is essentially `rustc`'s `main()` function. It acts as
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the glue for running the various phases of the compiler in the correct order,
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managing state such as the [`SourceMap`] \(maps AST nodes to source code),
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[`Session`] \(general build context and error messaging) and the [`TyCtxt`]
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\(the "typing context", allowing you to query the type system and other cool
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stuff). The `rustc_driver` crate also provides external users with a method
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using the interface defined in the [`rustc_interface`] crate.
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The `rustc_interface` crate provides external users with an (unstable) API
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for running code at particular times during the compilation process, allowing
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third parties to effectively use `rustc`'s internals as a library for
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analysing a crate or emulating the compiler in-process (e.g. the RLS).
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analysing a crate or emulating the compiler in-process (e.g. the RLS or rustdoc).
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For those using `rustc` as a library, the `run_compiler()` function is the main
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entrypoint to the compiler. Its main parameters are a list of command-line
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arguments and a reference to something which implements the `CompilerCalls`
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trait. A `CompilerCalls` creates the overall `CompileController`, letting it
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govern which compiler passes are run and attach callbacks to be fired at the end
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of each phase.
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For those using `rustc` as a library, the `interface::run_compiler()` function is the main
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entrypoint to the compiler. It takes a configuration for the compiler and a closure that
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takes a [`Compiler`]. `run_compiler` creates a `Compiler` from the configuration and passes
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it to the closure. Inside the closure, you can use the `Compiler` to drive queries to compile
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a crate and get the results. This is what the `rustc_driver` does too.
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From `rustc_driver`'s perspective, the main phases of the compiler are:
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You can see what queries are currently available through the rustdocs for [`Compiler`].
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You can see an example of how to use them by looking at the `rustc_driver` implementation,
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specifically the [`rustc_driver::run_compiler` function][rd_rc] (not to be confused with
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`interface::run_compiler`). The `rustc_driver::run_compiler` function takes a bunch of
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command-line args and some other configurations and drives the compilation to completion.
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1. *Parse Input:* Initial crate parsing
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2. *Configure and Expand:* Resolve `#[cfg]` attributes, name resolution, and
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expand macros
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3. *Run Analysis Passes:* Run trait resolution, typechecking, region checking
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and other miscellaneous analysis passes on the crate
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4. *Translate to LLVM:* Translate to the in-memory form of LLVM IR and turn it
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into an executable/object files
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The `CompileController` then gives users the ability to inspect the ongoing
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compilation process
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- after parsing
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- after AST expansion
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- after HIR lowering
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- after analysis, and
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- when compilation is done
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The `CompileState`'s various `state_after_*()` constructors can be inspected to
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determine what bits of information are available to which callback.
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For a more detailed explanation on using `rustc_driver`, check out the
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[stupid-stats] guide by `@nrc` (attached as [Appendix A]).
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`rustc_driver::run_compiler` also takes a [`Callbacks`][cb]. In the past, when
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the `rustc_driver::run_compiler` was the primary way to use the compiler as a
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library, these callbacks were used to have some custom code run after different
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phases of the compilation. If you read [Appendix A], you may notice the use of the
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types `CompilerCalls` and `CompileController`, which no longer exist. `Callbacks`
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replaces this functionality.
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> **Warning:** By its very nature, the internal compiler APIs are always going
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> to be unstable. That said, we do try not to break things unnecessarily.
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@ -54,21 +40,16 @@ manifests itself in the way people can plug into the compiler, preferring a
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"push"-style API (callbacks) instead of the more Rust-ic "pull" style (think
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the `Iterator` trait).
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For example the [`CompileState`], the state passed to callbacks after each
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phase, is essentially just a box of optional references to pieces inside the
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compiler. The lifetime bound on the `CompilerCalls` trait then helps to ensure
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compiler internals don't "escape" the compiler (e.g. if you tried to keep a
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reference to the AST after the compiler is finished), while still letting users
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record *some* state for use after the `run_compiler()` function finishes.
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Thread-local storage and interning are used a lot through the compiler to reduce
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duplication while also preventing a lot of the ergonomic issues due to many
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pervasive lifetimes. The `rustc::ty::tls` module is used to access these
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thread-locals, although you should rarely need to touch it.
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[cb]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/trait.Callbacks.html
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[rd_rc]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/fn.run_compiler.html
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[`rustc_interface`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/index.html
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[`rustc_driver`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/
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[`CompileState`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/driver/struct.CompileState.html
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[`Compiler`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/interface/struct.Compiler.html
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[`Session`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc/session/struct.Session.html
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[`TyCtxt`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc/ty/struct.TyCtxt.html
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[`SourceMap`]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.SourceMap.html
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|
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@ -172,7 +172,7 @@ Chalk's functionality is broken up into the following crates:
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- `coherence`, which implements coherence rules
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- Also includes [chalki][chalki], chalk's REPL.
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[Browse source code on GitHub](https://github.com/rust-lang-nursery/chalk)
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[Browse source code on GitHub](https://github.com/rust-lang/chalk)
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## Testing
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@ -202,8 +202,8 @@ Likewise, lowering tests use the [`lowering_success!` and
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## More Resources
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* [Chalk Source Code](https://github.com/rust-lang-nursery/chalk)
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* [Chalk Glossary](https://github.com/rust-lang-nursery/chalk/blob/master/GLOSSARY.md)
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* [Chalk Source Code](https://github.com/rust-lang/chalk)
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* [Chalk Glossary](https://github.com/rust-lang/chalk/blob/master/GLOSSARY.md)
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### Blog Posts
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@ -224,34 +224,34 @@ Likewise, lowering tests use the [`lowering_success!` and
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[wf-checking]: ./wf.html
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[ast]: https://en.wikipedia.org/wiki/Abstract_syntax_tree
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[chalk]: https://github.com/rust-lang-nursery/chalk
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[rustc-issues]: https://github.com/rust-lang-nursery/rustc-guide/issues
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[chalk]: https://github.com/rust-lang/chalk
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[rustc-issues]: https://github.com/rust-lang/rustc-guide/issues
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[universal quantification]: https://en.wikipedia.org/wiki/Universal_quantification
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|
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[`ProgramClause`]: https://rust-lang-nursery.github.io/chalk/doc/chalk_ir/enum.ProgramClause.html
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[`ProgramEnvironment`]: https://rust-lang-nursery.github.io/chalk/doc/chalk_ir/struct.ProgramEnvironment.html
|
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[chalk_engine]: https://rust-lang-nursery.github.io/chalk/doc/chalk_engine/index.html
|
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[chalk_ir]: https://rust-lang-nursery.github.io/chalk/doc/chalk_ir/index.html
|
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[chalk_parse]: https://rust-lang-nursery.github.io/chalk/doc/chalk_parse/index.html
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[chalk_solve]: https://rust-lang-nursery.github.io/chalk/doc/chalk_solve/index.html
|
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[doc-chalk]: https://rust-lang-nursery.github.io/chalk/doc/chalk/index.html
|
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[engine-context]: https://rust-lang-nursery.github.io/chalk/doc/chalk_engine/context/index.html
|
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[rust_ir-program]: https://rust-lang-nursery.github.io/chalk/doc/chalk/rust_ir/struct.Program.html
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[rust_ir]: https://rust-lang-nursery.github.io/chalk/doc/chalk/rust_ir/index.html
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[`ProgramClause`]: https://rust-lang.github.io/chalk/doc/chalk_ir/enum.ProgramClause.html
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[`ProgramEnvironment`]: https://rust-lang.github.io/chalk/doc/chalk_ir/struct.ProgramEnvironment.html
|
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[chalk_engine]: https://rust-lang.github.io/chalk/doc/chalk_engine/index.html
|
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[chalk_ir]: https://rust-lang.github.io/chalk/doc/chalk_ir/index.html
|
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[chalk_parse]: https://rust-lang.github.io/chalk/doc/chalk_parse/index.html
|
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[chalk_solve]: https://rust-lang.github.io/chalk/doc/chalk_solve/index.html
|
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[doc-chalk]: https://rust-lang.github.io/chalk/doc/chalk/index.html
|
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[engine-context]: https://rust-lang.github.io/chalk/doc/chalk_engine/context/index.html
|
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[rust_ir-program]: https://rust-lang.github.io/chalk/doc/chalk/rust_ir/struct.Program.html
|
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[rust_ir]: https://rust-lang.github.io/chalk/doc/chalk/rust_ir/index.html
|
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|
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[binders-struct]: https://github.com/rust-lang-nursery/chalk/blob/94a1941a021842a5fcb35cd043145c8faae59f08/src/ir.rs#L661
|
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[chalk-ast]: https://github.com/rust-lang-nursery/chalk/blob/master/chalk-parse/src/ast.rs
|
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[chalk-test-example]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L115
|
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[chalk-test-lowering-example]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rust_ir/lowering/test.rs#L8-L31
|
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[chalk-test-lowering]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rust_ir/lowering/test.rs
|
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[chalk-test-wf]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules/wf/test.rs#L1
|
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[chalki]: https://rust-lang-nursery.github.io/chalk/doc/chalki/index.html
|
||||
[clause]: https://github.com/rust-lang-nursery/chalk/blob/master/GLOSSARY.md#clause
|
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[coherence-src]: https://github.com/rust-lang-nursery/chalk/blob/master/src/coherence.rs
|
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[ir-code]: https://github.com/rust-lang-nursery/chalk/blob/master/src/rust_ir.rs
|
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[rules-environment]: https://github.com/rust-lang-nursery/chalk/blob/94a1941a021842a5fcb35cd043145c8faae59f08/src/rules.rs#L9
|
||||
[rules-src]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules.rs
|
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[rules-wf-src]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules/wf.rs
|
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[solve_goal]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L85
|
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[test-lowering-macros]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test_util.rs#L21-L54
|
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[test-macro]: https://github.com/rust-lang-nursery/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L33
|
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[binders-struct]: https://github.com/rust-lang/chalk/blob/94a1941a021842a5fcb35cd043145c8faae59f08/src/ir.rs#L661
|
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[chalk-ast]: https://github.com/rust-lang/chalk/blob/master/chalk-parse/src/ast.rs
|
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[chalk-test-example]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L115
|
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[chalk-test-lowering-example]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rust_ir/lowering/test.rs#L8-L31
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[chalk-test-lowering]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rust_ir/lowering/test.rs
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[chalk-test-wf]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules/wf/test.rs#L1
|
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[chalki]: https://rust-lang.github.io/chalk/doc/chalki/index.html
|
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[clause]: https://github.com/rust-lang/chalk/blob/master/GLOSSARY.md#clause
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[coherence-src]: https://github.com/rust-lang/chalk/blob/master/src/coherence.rs
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[ir-code]: https://github.com/rust-lang/chalk/blob/master/src/rust_ir.rs
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[rules-environment]: https://github.com/rust-lang/chalk/blob/94a1941a021842a5fcb35cd043145c8faae59f08/src/rules.rs#L9
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[rules-src]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules.rs
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[rules-wf-src]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/rules/wf.rs
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[solve_goal]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L85
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[test-lowering-macros]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test_util.rs#L21-L54
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[test-macro]: https://github.com/rust-lang/chalk/blob/4bce000801de31bf45c02f742a5fce335c9f035f/src/test.rs#L33
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|
|
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|
@ -47,7 +47,7 @@ well as the various *strands*, which are basically suspended
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computations that may be used to find more answers. Tables are
|
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interdependent: solving one query may require solving others.
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|
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[`Forest`]: https://rust-lang-nursery.github.io/chalk/doc/chalk_engine/forest/struct.Forest.html
|
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[`Forest`]: https://rust-lang.github.io/chalk/doc/chalk_engine/forest/struct.Forest.html
|
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### Walkthrough
|
||||
|
||||
|
|
@ -150,7 +150,7 @@ is the subgoal after the turnstile (`:-`) that we are currently trying
|
|||
to prove in this strand. Initally, when a strand is first created,
|
||||
there is no selected subgoal.
|
||||
|
||||
[`ExClause`]: https://rust-lang-nursery.github.io/chalk/doc/chalk_engine/struct.ExClause.html
|
||||
[`ExClause`]: https://rust-lang.github.io/chalk/doc/chalk_engine/struct.ExClause.html
|
||||
|
||||
**Activating a strand.** Now that we have created the table T0 and
|
||||
initialized it with strands, we have to actually try and produce an answer.
|
||||
|
|
@ -187,7 +187,7 @@ Here, we write `selected(L, An)` to indicate that (a) the literal `L`
|
|||
is the selected subgoal and (b) which answer `An` we are looking for. We
|
||||
start out looking for `A0`.
|
||||
|
||||
[`ensure_root_answer`]: https://rust-lang-nursery.github.io/chalk/doc/chalk_engine/forest/struct.Forest.html#method.ensure_root_answer
|
||||
[`ensure_root_answer`]: https://rust-lang.github.io/chalk/doc/chalk_engine/forest/struct.Forest.html#method.ensure_root_answer
|
||||
|
||||
**Processing the selected subgoal.** Next, we have to try and find an
|
||||
answer to this selected goal. To do that, we will u-canonicalize it
|
||||
|
|
@ -297,6 +297,6 @@ more answers later on.
|
|||
- [Negative Reasoning in Chalk][negative-reasoning-blog] explains the need
|
||||
for negative reasoning, but not how the SLG solver does it
|
||||
|
||||
[readme]: https://github.com/rust-lang-nursery/chalk/blob/239e4ae4e69b2785b5f99e0f2b41fc16b0b4e65e/chalk-engine/src/README.md
|
||||
[readme]: https://github.com/rust-lang/chalk/blob/239e4ae4e69b2785b5f99e0f2b41fc16b0b4e65e/chalk-engine/src/README.md
|
||||
[slg-blog]: http://smallcultfollowing.com/babysteps/blog/2018/01/31/an-on-demand-slg-solver-for-chalk/
|
||||
[negative-reasoning-blog]: http://aturon.github.io/blog/2017/04/24/negative-chalk/
|
||||
|
|
|
|||
Loading…
Reference in New Issue