Reimplement std's thread parker on top of events on SGX
Mutex and Condvar are being replaced by more efficient implementations, which need thread parking themselves (see #93740). Therefore, the generic `Parker` needs to be replaced on all platforms where the new lock implementation will be used.
SGX enclaves have a per-thread event state, which allows waiting for and setting specific bits. This is already used by the current mutex implementation. The thread parker can however be much more efficient, as it only needs to store the `TCS` address of one thread. This address is stored in a state variable, which can also be set to indicate the thread was already notified.
`park_timeout` does not guard against spurious wakeups like the current condition variable does. This is allowed by the API of `Parker`, and I think it is better to let users handle these wakeups themselves as the guarding is quite expensive and might not be necessary.
`@jethrogb` as you wrote the initial SGX support for `std`, I assume you are the target maintainer? Could you help me test this, please? Lacking a x86_64 chip, I can't run SGX.
They *are* representable by traits, even if the short-circuiting
behaviour requires a different approach than the non-short-circuiting
operators. For an example proposal, see the postponed RFC 2722.
As it is not accurate, reword the note.
Rollup of 9 pull requests
Successful merges:
- #102406 (Make `missing_copy_implementations` more cautious)
- #105265 (Add `rustc_on_unimplemented` to `Sum` and `Product` trait.)
- #105385 (Skip test on s390x as LLD does not support the platform)
- #105453 (Make `VecDeque::from_iter` O(1) from `vec(_deque)::IntoIter`)
- #105468 (Mangle "main" as "__main_void" on wasm32-wasi)
- #105480 (rustdoc: remove no-op mobile CSS `#sidebar-toggle { text-align }`)
- #105489 (Fix typo in apple_base.rs)
- #105504 (rustdoc: make stability badge CSS more consistent)
- #105506 (Tweak `rustc_must_implement_one_of` diagnostic output)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: remove no-op mobile CSS `#sidebar-toggle { text-align }`
Since 8b001b4da0 make the sidebar toggle a flex container, and already centers its content in desktop mode, this rule doesn't do anything.
Mangle "main" as "__main_void" on wasm32-wasi
On wasm, the age-old C trick of having a main function which can either have no arguments or argc+argv doesn't work, because wasm requires caller and callee signatures to match. WASI's current strategy is to have compilers mangle main's name to indicate which signature they're using. Rust uses the no-argument form, which should be mangled as `__main_void`.
This is needed on wasm32-wasi as of #105395.
Make `VecDeque::from_iter` O(1) from `vec(_deque)::IntoIter`
As suggested in https://github.com/rust-lang/rust/pull/105046#issuecomment-1330371695 by
r? ``@the8472``
`Vec` & `VecDeque`'s `IntoIter`s own the allocations, and even if advanced can be turned into `VecDeque`s in O(1).
This is just a specialization, not an API or doc commitment, so I don't think it needs an FCP.
Skip test on s390x as LLD does not support the platform
test/run-make/issue-71519 requires use of lld as linker, but lld does not currently support the s390x architecture.
Make `missing_copy_implementations` more cautious
- Fixes https://github.com/rust-lang/rust/issues/98348
- Also makes the lint not fire on large types and types containing raw pointers. Thoughts?
Shrink `rustc_parse_format::Piece`
This makes both variants closer together in size (previously they were different by 208 bytes -- 16 vs 224). This may make things worse, but it's worth a try.
r? `@nnethercote`
* They all get rounded corners now. A test case has been added for this, too.
* There are now broadly two kinds of stability badge, where there used to be
three: item-info "fat badge", and the "thin badge" in both item tables and
in docblocks (which got merged). The fat badges can have icons, while the
thin badges can't.
Clippy: backport ICE fix before beta branch
r? `@Manishearth`
Before beta is branched tomorrow we should backport the fix from https://github.com/rust-lang/rust-clippy/pull/10027 for an ICE. That way we'll get this into stable one release sooner.
This only cherry-picks the fix, not the tests for it. The proper sync of this will be done next week Thursday.
use the correct `Reveal` during validation
supersedes #105454. Deals with https://github.com/rust-lang/rust/issues/105009#issuecomment-1342395333, not closing #105009 as the ICE may leak into beta
The issue was the following:
- we optimize the mir, using `Reveal::All`
- some optimization relies on the hidden type of an opaque type
- we then validate using `Reveal::UserFacing` again which is not able to observe the hidden type
r? `@jackh726`
Move some queries and methods
Each commit's title should be self-explanatory. Motivated to break up some large, general files and move queries into leaf crates.
Dont silently ignore rustdoc errors
I applied the suggestions from https://github.com/rust-lang/rust/pull/104995 and also checked the rustdoc-ui error but couldn't reproduce it.
r? `@notriddle`
Enable profiler in dist-powerpc64le-linux
Build the profiler runtime to allow using -C profile-generate and -C instrument-coverage on POWER little endian systems.
I have verified locally that the runtime builds and the profiler is working fine on the platform.
Similar pull request for a different system: https://github.com/rust-lang/rust/pull/104304
Improve Rustdoc scrape-examples UI
This PR combines a few different improvements to the scrape-examples UI. See a live demo here: https://willcrichton.net/misc/scrape-examples/small-first-example/clap/struct.Arg.html
### 1. The first scraped example now takes up significantly less screen height.
Inserting the first scraped example takes up a lot of vertical screen space. I don't want this addition to overwhelm users, so I decided to reduce the height of the initial example in two ways: (A) the default un-expanded height is reduced from 240px (10 LOC) to 120px (5 LOC), and (B) the link to the example is now positioned *over* the example instead of *atop* the example (only on desktop though, not mobile). The changes to `scrape-examples.js` and `rustdoc.css` implement this fix.
Here is what an example docblock now looks like:
![Screen Shot 2022-12-06 at 10 02 21 AM](https://user-images.githubusercontent.com/663326/205987450-3940063c-5973-4a34-8579-baff6a43aa9b.png)
### 2. Expanding all docblocks will not expand "More examples".
The "More examples blocks" are huge, so fully expanding everything on the page would take up too much vertical space. The changes to `main.js` implement this fix. This is tested in `scrape-examples-toggle.goml`.
### 3. Examples from binary crates are sorted higher than examples from library crates.
Code that is written as an example of an API is probably better for learning than code that happens to use an API, but isn't intended for pedagogic purposes. Unfortunately Rustc doesn't know whether a particular crate comes from an example target (only Cargo knows this). But we can at least create a proxy that prefers examples from binary crates over library crates, which we know from `--crate-type`.
This change is implemented by adding a new field `bin_crate` in `Options` (see `config.rs`). An `is_bin` field has been added to the scraped examples metadata (see `scrape_examples.rs`). Then the example sorting metric uses `is_bin` as the first entry of a lexicographic sort on `(is_bin, example_size, display_name)` (see `render/mod.rs`).
Note that in the future we can consider adding another flag like `--scrape-examples-cargo-target` that would pass target information from Cargo into the example metadata. But I'm proposing a less intrusive change for now.
### 4. The scrape-examples help page has been updated to reflect the latest Cargo interface.
See `scrape-examples-help.md`.
r? `@notriddle`
P.S. once this PR and rust-lang/cargo#11450 are merged, then I think the scrape-examples feature is officially ready for deployment on docs.rs!
attempt to clarify align_to docs
This is not intended the change the docs at all, but `@workingjubilee` said the current docs are incomprehensible to some people so this is an attempt to fix that. No idea if it helps, so -- feedback welcome.
(Please let's not use this to discuss *changing* the spec. Whoever wants to change the spec should please make a separate PR for that.)
Rollup of 10 pull requests
Successful merges:
- #104922 (Detect long types in E0308 and write them to disk)
- #105120 (kmc-solid: `std::sys` code maintenance)
- #105255 (Make nested RPIT inherit the parent opaque's generics.)
- #105317 (make retagging work even with 'unstable' places)
- #105405 (Stop passing -export-dynamic to wasm-ld.)
- #105408 (Add help for `#![feature(impl_trait_in_fn_trait_return)]`)
- #105423 (Use `Symbol` for the crate name instead of `String`/`str`)
- #105433 (CI: add missing line continuation marker)
- #105434 (Fix warning when libcore is compiled with no_fp_fmt_parse)
- #105441 (Remove `UnsafetyState`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
In order for LLVM to correctly generate debuginfo for msvc, we sometimes
need to spill arguments to the stack and perform some direct & indirect
offsets into the value. Previously, this code always performed those
actions, even when not required as LLVM would clean it up during
optimization.
However, when MIR inlining is enabled, this can cause problems as the
operations occur prior to the spilled value being initialized. To solve
this, we first calculate the necessary offsets using just the type which
is side-effect free and does not alter the LLVM IR. Then, if we are in a
situation which requires us to generate the LLVM IR (and this situation
only occurs for arguments, not local variables) then we perform the same
calculation again, this time generating the appropriate LLVM IR as we
go.