Add "algebraic" fast-math intrinsics, based on fast-math ops that cannot return poison
Setting all of LLVM's fast-math flags makes our fast-math intrinsics very dangerous, because some inputs are UB. This set of flags permits common algebraic transformations, but according to the [LangRef](https://llvm.org/docs/LangRef.html#fastmath), only the flags `nnan` (no nans) and `ninf` (no infs) can produce poison.
And this uses the algebraic float ops to fix https://github.com/rust-lang/rust/issues/120720
cc `@orlp`
match lowering: simplify empty candidate selection
In match lowering, `match_simplified_candidates` is tasked with removing candidates that are fully matched and linking them up properly. The code that does that was needlessly complicated; this PR simplifies it.
The overall change isn't big but I split it up into tiny commits to convince myself that I was correctly preserving behavior. The test changes are all due to the first commit. Let me know if you'd prefer me to split up the PR to make reviewing easier.
r? `@matthewjasper`
match lowering: eagerly simplify match pairs
This removes one important complication from match lowering. Before this, match pair simplification (which includes collecting bindings and type ascriptions) was intertwined with the whole match lowering algorithm.
I'm avoiding this by storing in each `MatchPair` the sub-`MatchPair`s that correspond to its subfields. This makes it possible to simplify everything (except or-patterns) in `Candidate::new()`.
This should open up further simplifications. It will also give us proper control over the order of bindings.
r? `@matthewjasper`
Use intrinsics::debug_assertions in debug_assert_nounwind
This is the first item in https://github.com/rust-lang/rust/issues/120848.
Based on the benchmarking in this PR, it looks like, for the programs in our benchmark suite, enabling all these additional checks does not introduce significant compile-time overhead, with the single exception of `Alignment::new_unchecked`. Therefore, I've added `#[cfg(debug_assertions)]` to that one call site, so that it remains compiled out in the distributed standard library.
The trailing commas in the previous calls to `debug_assert_nounwind!` were causing the macro to expand to `panic_nouwnind_fmt`, which requires more work to set up its arguments, and that overhead alone is measured between this perf run and the next: https://github.com/rust-lang/rust/pull/120863#issuecomment-1937423502
Overhaul `Diagnostic` and `DiagnosticBuilder`
Implements the first part of https://github.com/rust-lang/compiler-team/issues/722, which moves functionality and use away from `Diagnostic`, onto `DiagnosticBuilder`.
Likely follow-ups:
- Move things around, because this PR was written to minimize diff size, so some things end up in sub-optimal places. E.g. `DiagnosticBuilder` has impls in both `diagnostic.rs` and `diagnostic_builder.rs`.
- Rename `Diagnostic` as `DiagInner` and `DiagnosticBuilder` as `Diag`.
r? `@davidtwco`
Always evaluate free constants and statics, even if previous errors occurred
work towards https://github.com/rust-lang/rust/issues/79738
We will need to evaluate static items before the `definitions.freeze()` below, as we will start creating new `DefId`s (for nested allocations) within the `eval_static_initializer` query.
But even without that motivation, this is a good change. Hard errors should always be reported and not silenced if other errors happened earlier.
Rollup of 10 pull requests
Successful merges:
- #120716 (Change leak check and suspicious auto trait lint warning messages)
- #121195 (unstable-book: Separate testing and production sanitizers)
- #121205 (Merge `CompilerError::CompilationFailed` and `CompilerError::ICE`.)
- #121233 (Move the extra directives for `Mode::CoverageRun` into `iter_header`)
- #121256 (Allow AST and HIR visitors to return `ControlFlow`)
- #121307 (Drive-by `DUMMY_SP` -> `Span` and fmt changes)
- #121308 (Add regression test for #103369)
- #121310 (Remove an old hack for rustdoc)
- #121311 (Make `is_nonoverlapping` `#[inline]`)
- #121319 (return `ty::Error` when equating `ty::Error`)
r? `@ghost`
`@rustbot` modify labels: rollup
return `ty::Error` when equating `ty::Error`
This helps iron out a difference in diagnostics between `Sub` and `Equate` relations, which I'm currently trying to unify.
r? oli-obk
Drive-by `DUMMY_SP` -> `Span` and fmt changes
Noticed these while doing something else. There's no practical change, but it's preferable to use `DUMMY_SP` as little as possible, particularly when we have perfectlly useful `Span`s available.
Allow AST and HIR visitors to return `ControlFlow`
Alternative to #108598.
Since rust-lang/libs-team#187 was rejected, this implements our own version of the `Try` trait (`VisitorResult`) and the `try` macro (`try_visit`). Since this change still allows visitors to return `()`, no changes have been made to the existing ones. They can be done in a separate PR.
Move the extra directives for `Mode::CoverageRun` into `iter_header`
When these extra directives were ported over as part of #112300, it made sense to introduce `iter_header_extra` and pass them in as an extra argument.
But now that #120881 has added a `mode` parameter to `iter_header` for its own purposes, it's slightly simpler to move the coverage special-case code directly into `iter_header` as well. This lets us get rid of `iter_header_extra`.
Merge `CompilerError::CompilationFailed` and `CompilerError::ICE`.
`CompilerError` has `CompilationFailed` and `ICE` variants, which seems reasonable at first. But the way it identifies them is flawed:
- If compilation errors out, i.e. `RunCompiler::run` returns an `Err`, it uses `CompilationFailed`, which is reasonable.
- If compilation panics with `FatalError`, it catches the panic and uses `ICE`. This is sometimes right, because ICEs do cause `FatalError` panics, but sometimes wrong, because certain compiler errors also cause `FatalError` panics. (The compiler/rustdoc/clippy/whatever just catches the `FatalError` with `catch_with_exit_code` in `main`.)
In other words, certain non-ICE compilation failures get miscategorized as ICEs. It's not possible to reliably distinguish the two cases, so this commit merges them. It also renames the combined variant as just `Failed`, to better match the existing `Interrupted` and `Skipped` variants.
Here is an example of a non-ICE failure that causes a `FatalError` panic, from `tests/ui/recursion_limit/issue-105700.rs`:
```
#![recursion_limit="4"]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
//~^ERROR recursion limit reached while expanding
fn main() {{}}
```
r? ``@spastorino``
unstable-book: Separate testing and production sanitizers
This is a redo of [this PR](https://github.com/rust-lang/rust/pull/108942). Left the commit as before (except for reflowing to 80-width), since it already got approved.
Change leak check and suspicious auto trait lint warning messages
The leak check lint message "this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!" is misleading as some cases may not be phased out and could end being accepted. This is under discussion still.
The suspicious auto trait lint the change in behavior already happened, so the new message is probably more accurate.
r? `@lcnr`
Closes#93367
pattern_analysis: Move constructor selection logic to `PlaceInfo`
This is a small refactor PR. There was a dense bit of constructor-related logic in `compute_exhaustiveness_and_usefulness`. I'm moving it out into a `PlaceInfo` method to make it easier to follow both separately. I also have plans that will complicate it further so it's good that it's somewhat encapsulated.
r? `@compiler-errors`
Reimpl meaningful test name lint MCP658
This reintroduces the tidy rule originally proposed in https://github.com/rust-lang/rust/pull/113583 that then became an MCP in https://github.com/rust-lang/compiler-team/issues/658 which eventually surfaced a quite-reasonable request for a diagnostic enhancement. I have added that to the rule. It produces output like this:
```
tidy error: file `ui/unsized/issue-115809.rs` must begin with a descriptive name, try `{reason}-issue-115809.rs`
tidy error: file `ui/unsized/issue-115203.rs` must begin with a descriptive name, try `{reason}-issue-115203.rs`
tidy error: file `ui/privacy/issue-113860-2.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/privacy/issue-117997.rs` must begin with a descriptive name, try `{reason}-issue-117997.rs`
tidy error: file `ui/privacy/issue-119463.rs` must begin with a descriptive name, try `{reason}-issue-119463.rs`
tidy error: file `ui/privacy/auxiliary/issue-117997.rs` must begin with a descriptive name, try `{reason}-issue-117997.rs`
tidy error: file `ui/privacy/auxiliary/issue-119463-extern.rs` must begin with a descriptive name, try `{reason}-issue-119463.rs`
tidy error: file `ui/privacy/issue-113860-1.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/privacy/issue-113860.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/const-generics/generic_const_exprs/const_kind_expr/issue_114151.rs` must begin with a descriptive name, try `{reason}-issue-114151.rs`
tidy error: file `ui/did_you_mean/issue-114112.rs` must begin with a descriptive name, try `{reason}-issue-114112.rs`
tidy error: file `ui/did_you_mean/issue-105225.rs` must begin with a descriptive name, try `{reason}-issue-105225.rs`
tidy error: file `ui/did_you_mean/issue-105225-named-args.rs` must begin with a descriptive name, try `{reason}-issue-105225.rs`
```
You get the idea.
There are some tests which merely would require reordering of the name according to the rule. I could modify the diagnostic further to identify those, but doing such would make it prone to bad suggestions. I have opted to trust contributors to recognize the diagnostic is robotic, as the pattern we are linting on is easier to match if we do not speculate on what parts of the name are meaningful: sometimes a word is a reason, but sometimes it is a mere "tag", such as with a pair like:
- issue-314159265-blue.rs
- issue-314159265-red.rs
Starting them with `red-` and `blue-` means they do not sort together, despite being related, and the color names are still not very descriptive. Recognizing a good name is an open-ended task, though this pair might be:
- colored-circle-gen-blue.rs
- colored-circle-gen-red.rs
Deciding exactly *how* to solve this is not the business of tidy, only recognizing a what.
r? `@compiler-errors`
deduplicate infer var instantiation
Having 3 separate implementations of one of the most subtle parts of our type system is not a good strategy if we want to maintain a sound type system ✨ while working on this I already found some subtle bugs in the existing code, so that's awesome 🎉 cc #121159
This was necessary as I am not confident in my nll changes in #119106, so I am first cleaning this up in a separate PR.
r? `@BoxyUwU`
distribute tool documentations and avoid file conflicts on `x install`
I suggest reading commits one-by-one with the descriptions for more context about the changes.
Fixes#115213
Specialize some methods of `io::Chain`
This PR specializes the implementation of some methods of `io::Chain`, which could bring performance improvements when using it.
Portable SIMD subtree update
Syncs nightly to the latest changes from rust-lang/portable-simd
r? `@rust-lang/libs`
Also, fixes#119904 which is now fixed upstream.
macro_rules: Preserve all metavariable spans in a global side table
This PR preserves spans of `tt` metavariables used to pass tokens to declarative macros.
Such metavariable spans can then be used in span combination operations like `Span::to` to improve all kinds of diagnostics.
Spans of non-`tt` metavariables are currently kept in nonterminal tokens, but the long term plan is remove all nonterminal tokens from rustc parser and rely on the proc macro model with invisible delimiters (#114647, #67062).
In particular, `NtIdent` nonterminal (corresponding to `ident` metavariables) becomes easy to remove when this PR lands (#119412 does it).
The metavariable spans are kept in a global side table keyed by `Span`s of original tokens.
The alternative to the side table is keeping them in `SpanData` instead, but the performance regressions would be large because any spans from tokens passed to declarative macros would stop being inline and would work through span interner instead, and the penalty would be paid even if we never use the metavar span for the given original span.
(But also see the comment on `fn maybe_use_metavar_location` describing the map collision issues with the side table approach.)
There are also other alternatives - keeping the metavar span in `Token` or `TokenTree`, but associating it with `Span` itsel is the most natural choice because metavar spans are used in span combining operations, and those operations are not necessarily tied to tokens.
Tracking import use types for more accurate redundant import checking
fixes#117448
By tracking import use types to check whether it is scope uses or the other situations like module-relative uses, we can do more accurate redundant import checking.
For example unnecessary imports in std::prelude that can be eliminated:
```rust
use std::option::Option::Some;//~ WARNING the item `Some` is imported redundantly
use std::option::Option::None; //~ WARNING the item `None` is imported redundantly
```
fixes#117448
For example unnecessary imports in std::prelude that can be eliminated:
```rust
use std::option::Option::Some;//~ WARNING the item `Some` is imported redundantly
use std::option::Option::None; //~ WARNING the item `None` is imported redundantly
```
Properly deal with weak alias types as self types of impls
Fixes#114216.
Fixes#116100.
Not super happy about the two ad hoc “normalization” implementations for weak alias types:
1. In `inherent_impls`: The “peeling”, normalization to [“WHNF”][whnf]: Semantically that's exactly what we want (neither proper normalization nor shallow normalization would be correct here). Basically a weak alias type is “nominal” (well...^^) if the WHNF is nominal. [#97974](https://github.com/rust-lang/rust/pull/97974) followed the same approach.
2. In `constrained_generic_params`: Generic parameters are constrained by a weak alias type if the corresp. “normalized” type constrains them (where we only normalize *weak* alias types not arbitrary ones). Weak alias types are injective if the corresp. “normalized” type is injective.
Both have ad hoc overflow detection mechanisms.
**Coherence** is handled in #117164.
r? `@oli-obk` or types
[whnf]: https://en.wikipedia.org/wiki/Lambda_calculus_definition#Weak_head_normal_form
Make `io::BorrowedCursor::advance` safe
This also keeps the old `advance` method under `advance_unchecked` name.
This makes pattern like `std::io::default_read_buf` safe to write.
Support configuring the set of codegen backends to build per host triple
This allows building the compiler itself with one backend while using another backend at runtime. For example this allows compiling rustc to wasm using LLVM, while using Cranelift at runtime to produce actual code. Cranelift can't compile to wasm, but is perfectly capable of running on wasm. LLVM can compile to wasm, but can't run on wasm. [^1]
[^1]: The prototype of this still requires a couple of other patches.
fix: Fix snippets being placed leftwards of where they should be
Snippet bits were being escaped before placing snippets, shifting snippets leftwards. Snippets were also being shifted leftwards on files with CRLF line endings since they were placed done after the Unix -> DOS line ending conversion.
Hoping this fixes all of the little bugs related to snippet rendering 😅
internal: Parse (nightly) `const` and `async` trait bounds
Both of these bound modifiers were added recently:
* `const` trait bounds: https://github.com/rust-lang/rust/pull/119099
* `async` trait bounds: https://github.com/rust-lang/rust/pull/120392
The latter will certainly will not do the right thing; namely, `async Fn` needs to be mapped to the `AsyncFn` trait. IDK how to do that, so advice would be appreciated, though perhaps we could land this first so the parser isn't complaining about these bounds?
ci: Update GitHub Actions and Node version
Use newer versions of actions; Node 16 -> 18
Fix several warnings in the actions tab regarding usage of the EOL Node 16
Rename MaybeUninit::write_slice
A step to push #79995 forward.
https://github.com/rust-lang/libs-team/issues/122 also suggested to make them inherent methods, but they can't be — they'd conflict with slice's regular methods.
fix: Don't show type mismatches for `{unknown}` to non-`{unknown}` mismatches
Fixes https://github.com/rust-lang/rust-analyzer/issues/15704
Basically we zip the two types, inspecting their substitutions if the constructors are the same, if we encounter a zip step with an `{unknown}` on one side and a non-`{unknown}` on the other we error out and discard the diagnostic. Otherwise we keep it.
