coverage: Rename `mir::coverage::BranchInfo` to `CoverageInfoHi`
This opens the door to collecting and storing coverage information that is unrelated to branch coverage or MC/DC, during MIR building.
There is no change to the output of coverage instrumentation, but one deliberate change is that functions now *always* have an attached `CoverageInfoHi` (if coverage is enabled and they are eligible), even if they didn't collect any interesting branch information.
---
`@rustbot` label +A-code-coverage
DependencyList: removed outdated comment
Comment was outdated. Didn't updated description, as `Linkage` enum have descriptive names.
Also added fixme about moving this file to rustc_metadata.
Match ergonomics 2024: Implement TC's match ergonomics proposal
Under gate `ref_pat_eat_one_layer_2024_structural`. Enabling `ref_pat_eat_one_layer_2024` at the same time allows the union of what the individual gates allow. `@traviscross`
r? `@Nadrieril`
cc https://github.com/rust-lang/rust/issues/123076
`@rustbot` label A-edition-2024 A-patterns
Miri function identity hack: account for possible inlining
Having a non-lifetime generic is not the only reason a function can be duplicated. Another possibility is that the function may be eligible for cross-crate inlining. So also take into account the inlining attribute in this Miri hack for function pointer identity.
That said, `cross_crate_inlinable` will still sometimes return true even for `inline(never)` functions:
- when they are `DefKind::Ctor(..) | DefKind::Closure` -- I assume those cannot be `InlineAttr::Never` anyway?
- when `cross_crate_inline_threshold == InliningThreshold::Always`
so maybe this is still not quite the right criterion to use for function pointer identity.
cache type sizes in type-size limit visitor
This is basically https://github.com/rust-lang/rust/pull/125507#issuecomment-2206813779 as lcnr can't open the PR now.
Locally it reduces the `itertools` regression by quite a bit, to "only +50%" compared to nightly (that includes overhead from the local lack of artifact post-processing, and is just a data point to compare to the 10-20x timings without the cache).
```console
Benchmark 1: cargo +stage1 build --release
Time (mean ± σ): 2.721 s ± 0.009 s [User: 2.446 s, System: 0.325 s]
Range (min … max): 2.710 s … 2.738 s 10 runs
Benchmark 2: cargo +nightly build --release
Time (mean ± σ): 1.784 s ± 0.005 s [User: 1.540 s, System: 0.279 s]
Range (min … max): 1.778 s … 1.792 s 10 runs
Summary
cargo +nightly build --release ran
1.52 ± 0.01 times faster than cargo +stage1 build --release
```
On master, it's from 34s to the 2.7s above.
r? compiler-errors
Rollup of 9 pull requests
Successful merges:
- #123043 (Disable dead variant removal for `#[repr(C)]` enums.)
- #126405 (Migrate some rustc_builtin_macros to SessionDiagnostic)
- #127037 (Remove some duplicated tests)
- #127283 (Reject SmartPointer constructions not serving the purpose)
- #127301 (Tweak some structured suggestions to be more verbose and accurate)
- #127307 (Allow to have different types for arguments of `Rustc::remap_path_prefix`)
- #127309 (jsondocck: add `$FILE` built-in variable)
- #127314 (Trivial update on tidy bless note)
- #127319 (Remove a use of `StructuredDiag`, which is incompatible with automatic error tainting and error translations)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove a use of `StructuredDiag`, which is incompatible with automatic error tainting and error translations
fixes#127219
I want to remove all of `StructuredDiag`, but it's a bit more involved as it is also used from the `ItemCtxt`, which doesn't support tainting yet.
Tweak some structured suggestions to be more verbose and accurate
Addressing some issues I found while working on #127282.
```
error: this URL is not a hyperlink
--> $DIR/auxiliary/include-str-bare-urls.md:1:11
|
LL | HEADS UP! https://example.com MUST SHOW UP IN THE STDERR FILE!
| ^^^^^^^^^^^^^^^^^^^
|
= note: bare URLs are not automatically turned into clickable links
note: the lint level is defined here
--> $DIR/include-str-bare-urls.rs:14:9
|
LL | #![deny(rustdoc::bare_urls)]
| ^^^^^^^^^^^^^^^^^^
help: use an automatic link instead
|
LL | HEADS UP! <https://example.com> MUST SHOW UP IN THE STDERR FILE!
| + +
```
```
error[E0384]: cannot assign twice to immutable variable `v`
--> $DIR/assign-imm-local-twice.rs:7:5
|
LL | v = 1;
| ----- first assignment to `v`
LL | println!("v={}", v);
LL | v = 2;
| ^^^^^ cannot assign twice to immutable variable
|
help: consider making this binding mutable
|
LL | let mut v: isize;
| +++
```
```
error[E0393]: the type parameter `Rhs` must be explicitly specified
--> $DIR/issue-22560.rs:9:23
|
LL | trait Sub<Rhs=Self> {
| ------------------- type parameter `Rhs` must be specified for this
...
LL | type Test = dyn Add + Sub;
| ^^^
|
= note: because of the default `Self` reference, type parameters must be specified on object types
help: set the type parameter to the desired type
|
LL | type Test = dyn Add + Sub<Rhs>;
| +++++
```
```
error[E0596]: cannot borrow `v` as mutable, as it is not declared as mutable
--> $DIR/issue-33819.rs:4:34
|
LL | Some(ref v) => { let a = &mut v; },
| ^^^^^^ cannot borrow as mutable
|
help: try removing `&mut` here
|
LL - Some(ref v) => { let a = &mut v; },
LL + Some(ref v) => { let a = v; },
|
```
```
help: remove the invocation before committing it to a version control system
|
LL - dbg!();
|
```
```
error[E0308]: mismatched types
--> $DIR/issue-39974.rs:1:21
|
LL | const LENGTH: f64 = 2;
| ^ expected `f64`, found integer
|
help: use a float literal
|
LL | const LENGTH: f64 = 2.0;
| ++
```
```
error[E0529]: expected an array or slice, found `Vec<i32>`
--> $DIR/match-ergonomics.rs:8:9
|
LL | [&v] => {},
| ^^^^ pattern cannot match with input type `Vec<i32>`
|
help: consider slicing here
|
LL | match x[..] {
| ++++
```
```
error[E0609]: no field `0` on type `[u32; 1]`
--> $DIR/parenthesized-deref-suggestion.rs:10:21
|
LL | (x as [u32; 1]).0;
| ^ unknown field
|
help: instead of using tuple indexing, use array indexing
|
LL | (x as [u32; 1])[0];
| ~ +
```
Reject SmartPointer constructions not serving the purpose
Tracking issue: #123430
With this PR we will reject a row of malformed `SmartPointer` implementor candidates.
cc `@Darksonn` `@davidtwco` for context.
Migrate some rustc_builtin_macros to SessionDiagnostic
<!--
If this PR is related to an unstable feature or an otherwise tracked effort,
please link to the relevant tracking issue here. If you don't know of a related
tracking issue or there are none, feel free to ignore this.
This PR will get automatically assigned to a reviewer. In case you would like
a specific user to review your work, you can assign it to them by using
r? <reviewer name>
-->
Part of https://github.com/rust-lang/rust/issues/100717.
pick up abandoned pr: #101935
`@rustbot` label +A-translation
Disable dead variant removal for `#[repr(C)]` enums.
This prevents removing dead branches from a `#[repr(C)]` enum (they now get discriminants allocated as if they were inhabited).
Implementation notes: ABI of something like
```rust
#[repr(C)]
enum Foo {
Foo(!),
}
```
is still `Uninhabited`, but its layout is now computed as if all the branches were inhabited.
This seemed to me like a proper way to do it, especially given that ABI sanity check explicitly asserts that type-level uninhabitedness implies ABI uninhabitedness.
This probably needs some sort of FCP (given that it changes `#[repr(C)]` layout, which is a stable guarantee), but I’m not sure how to call for one or which team is the most relevant.
See https://github.com/rust-lang/unsafe-code-guidelines/issues/500.
The rules for casting `*mut X<dyn A>` -> `*mut Y<dyn B>` are as follows:
- If `B` has a principal
- `A` must have exactly the same principal (including generics)
- Auto traits of `B` must be a subset of autotraits in `A`
Note that `X<_>` and `Y<_>` can be identity, or arbitrary structs with last field being the dyn type.
The lifetime of the trait object itself (`dyn ... + 'a`) is not checked.
This prevents a few soundness issues with `#![feature(arbitrary_self_types)]` and trait upcasting.
Namely, these checks make sure that vtable is always valid for the pointee.
Stop using specialization in rustc_index and rustc_borrowck
For rustc_borrowck the version with specialization isn't much more readable anyway IMO. For rustc_index it probably doesn't affect perf in any noticeable way anyway.
Optimize SipHash by reordering compress instructions
This PR optimizes hashing by changing the order of instructions in the sip.rs `compress` macro so the CPU can parallelize it better. The new order is taken directly from Fig 2.1 in [the SipHash paper](https://eprint.iacr.org/2012/351.pdf) (but with the xors moved which makes it a little faster). I attempted to optimize it some more after this, but I think this might be the optimal instruction order. Note that this shouldn't change the behavior of hashing at all, only statements that don't depend on each other were reordered.
It appears like the current order hasn't changed since its [original implementation from 2012](fada46c421 (diff-b751133c229259d7099bbbc7835324e5504b91ab1aded9464f0c48cd22e5e420R35)) which doesn't look like it was written with data dependencies in mind.
Running `./x bench library/core --stage 0 --test-args hash` before and after this change shows the following results:
Before:
```
benchmarks:
hash::sip::bench_bytes_4 7.20/iter +/- 0.70
hash::sip::bench_bytes_7 9.01/iter +/- 0.35
hash::sip::bench_bytes_8 8.12/iter +/- 0.10
hash::sip::bench_bytes_a_16 10.07/iter +/- 0.44
hash::sip::bench_bytes_b_32 13.46/iter +/- 0.71
hash::sip::bench_bytes_c_128 37.75/iter +/- 0.48
hash::sip::bench_long_str 121.18/iter +/- 3.01
hash::sip::bench_str_of_8_bytes 11.20/iter +/- 0.25
hash::sip::bench_str_over_8_bytes 11.20/iter +/- 0.26
hash::sip::bench_str_under_8_bytes 9.89/iter +/- 0.59
hash::sip::bench_u32 9.57/iter +/- 0.44
hash::sip::bench_u32_keyed 6.97/iter +/- 0.10
hash::sip::bench_u64 8.63/iter +/- 0.07
```
After:
```
benchmarks:
hash::sip::bench_bytes_4 6.64/iter +/- 0.14
hash::sip::bench_bytes_7 8.19/iter +/- 0.07
hash::sip::bench_bytes_8 8.59/iter +/- 0.68
hash::sip::bench_bytes_a_16 9.73/iter +/- 0.49
hash::sip::bench_bytes_b_32 12.70/iter +/- 0.06
hash::sip::bench_bytes_c_128 32.38/iter +/- 0.20
hash::sip::bench_long_str 102.99/iter +/- 0.82
hash::sip::bench_str_of_8_bytes 10.71/iter +/- 0.21
hash::sip::bench_str_over_8_bytes 11.73/iter +/- 0.17
hash::sip::bench_str_under_8_bytes 10.33/iter +/- 0.41
hash::sip::bench_u32 10.41/iter +/- 0.29
hash::sip::bench_u32_keyed 9.50/iter +/- 0.30
hash::sip::bench_u64 8.44/iter +/- 1.09
```
I ran this on my computer so there's some noise, but you can tell at least `bench_long_str` is significantly faster (~18%).
Also, I noticed the same compress function from the library is used in the compiler as well, so I took the liberty of copy-pasting this change to there as well.
Thanks `@semisol` for porting SipHash for another project which led me to notice this issue in Rust, and for helping investigate. <3
rustdoc: update to pulldown-cmark 0.11
r? rustdoc
This pull request updates rustdoc to the latest version of pulldown-cmark. Along with adding new markdown extensions (which this PR doesn't enable), the new pulldown-cmark version also fixes a large number of bugs. Because all text files successfully parse as markdown, these bugfixes change the output, which can break people's existing docs.
A crater run, https://github.com/rust-lang/rust/pull/121659, has already been run for this change.
The first commit upgrades and fixes rustdoc. The second commit adds a lint for the footnote and block quote parser changes, which break the largest numbers of docs in the Crater run. The strikethrough change was mitigated in pulldown-cmark itself.
Unblocks https://github.com/rust-lang/rust-clippy/pull/12876
Fix incorrect suggestion for extra argument with a type error
Fixes#126246
I tried to fix it in the `find_errors` of ArgMatrix, but seems it's hard to avoid breaking some other test cases.
The root cause is we eliminate the first argument even with a type error at here:
6292b2af62/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs (L664)
So the left argument is always treated as extra one.
But if there is already a type error, an error message will be generated firstly, which make this issue a trivial one.
