Enable ConstGoto and SeparateConstSwitch passes by default
These 2 passes implement a limited form of jump-threading.
Filing this PR to see if enabling them would be lighter than https://github.com/rust-lang/rust/pull/107009.
Enable ScalarReplacementOfAggregates in optimized builds
Like MatchBranchSimplification, this pass is known to produce significant runtime improvements in Cranelift artifacts, and I believe based on the perf runs here that the primary effect of this pass is to empower MatchBranchSimplification. ScalarReplacementOfAggregates on its own has little effect on anything, but when this was rebased up to include https://github.com/rust-lang/rust/pull/112001 we started seeing significant and majority-positive results.
Based on the fact that we see most of the regressions in debug builds (https://github.com/rust-lang/rust/pull/112002#issuecomment-1566270144) and some rather significant ones in cycles and wall time, I'm only enabling this in optimized builds at the moment.
remove reference to Into in ? operator core/std docs, fix#111655
remove the text stating that `?` uses `Into::into` and add text stating it uses `From::from` instead. This closes#111655.
Don't compute inlining status of mono items in advance.
We record inlining status for mono items in `MonoItems`, and then transfer it to `InliningMap`, for later use in
`InliningMap::with_inlining_candidates`.
But we can just compute inlining status directly in `InliningMap::with_inlining_candidates`, because the mono item is right there. There's no need to compute it in advance.
This commit changes the code to do that, removing the need for `MonoItems` and `InliningMap::inlines`. This does result in more calls to `instantiation_mode` (one per static occurrence) but the performance effect is negligible.
r? ``@wesleywiser``
Preserve substs in opaques recorded in typeck results
This means that we now prepopulate MIR with opaques with the right substs.
The first commit is a hack that I think we discussed, having to do with `DefiningAnchor::Bubble` basically being equivalent to `DefiningAnchor::Error` in the new solver, so having to use `DefiningAnchor::Bind` instead, lol.
r? `@lcnr`
rustdoc: add interaction delays for tooltip popovers
Preview:
* [notable traits](http://notriddle.com/rustdoc-demo-html-3/delay-tooltip/testing/struct.Vec.html#method.iter)
* [panicking code block](http://notriddle.com/rustdoc-demo-html-3/delay-tooltip/testing/struct.Vec.html#indexing)
Designing a good hover microinteraction is a matter of guessing user intent from what are, literally, vague gestures. In this case, guessing if hovering in our out of the tooltip base is intentional or not.
To figure this out, a few different techniques are used:
* When the mouse pointer enters a tooltip anchor point, its hitbox is grown on the bottom, where the popover is/will appear. This was already there before this commit: search "hover tunnel" in rustdoc.css for the implementation.
* This commit adds a delay when the mouse pointer enters the base anchor, in case the mouse pointer was just passing through and the user didn't want to open it.
* This commit also adds a delay when the mouse pointer exits the tooltip's base anchor or its popover, before hiding it.
* A fade-out animation is layered onto the pointer exit delay to immediately inform the user that they successfully dismissed the popover, while still providing a way for them to cancel it if it was a mistake and they still wanted to interact with it.
* No animation is used for revealing it, because we don't want people to try to interact with an element while it's in the middle of fading in: either they're allowed to interact with it while it's fading in, meaning it can't serve as mistake- proofing for opening the popover, or they can't, but they might try and be frustrated.
See also:
* https://www.nngroup.com/articles/timing-exposing-content/
* https://www.nngroup.com/articles/tooltip-guidelines/
* https://bjk5.com/post/44698559168/breaking-down-amazons-mega-dropdown
Add a distinct `OperandValue::ZeroSized` variant for ZSTs
These tend to have special handling in a bunch of places anyway, so the variant helps remember that. And I think it's easier to grok than `Aggregate`s sometimes being `Immediates` (after all, I previously got that wrong and caused #109992). As a minor bonus, it means we don't need to generate poison LLVM values for ZSTs to pass around in `OperandValue::Immediate`s.
Inspired by https://github.com/rust-lang/rust/pull/110021#discussion_r1160486991, so
r? `@compiler-errors`
rustdoc: Fix LinkReplacer link matching
It currently just uses the first link with the same href which might not necessarily be the matching one.
This fixes replacements when there are several links to the same item but with different text (e.g. `[X] and [struct@X]`). It also fixes replacements in summaries since those use a links list with empty hrefs, so currently all links would always match the first link by href but then not match its text. This could also lead to a panic in the `original_lext[1..len() - 1]` part when the first link only has a single character, which is why the new code uses `.get(..)` instead.
Replace const eval limit by a lint and add an exponential backoff warning
The lint triggers at the first power of 2 that comes after 1 million function calls or traversed back-edges (takes less than a second on usual programs). After the first emission, an unsilenceable warning is repeated at every following power of 2 terminators, causing it to get reported less and less the longer the evaluation runs.
cc `@rust-lang/wg-const-eval`
fixes#93481closes#67217
These tend to have special handling in a bunch of places anyway, so the variant helps remember that. And I think it's easier to grok than non-Scalar Aggregates sometimes being `Immediates` (like I got wrong and caused 109992). As a minor bonus, it means we don't need to generate poison LLVM values for them to pass around in `OperandValue::Immediate`s.
Uplift `clippy::cast_ref_to_mut` lint
This PR aims at uplifting the `clippy::cast_ref_to_mut` lint into rustc.
## `cast_ref_to_mut`
(deny-by-default)
The `cast_ref_to_mut` lint checks for casts of `&T` to `&mut T` without using interior mutability.
### Example
```rust,compile_fail
fn x(r: &i32) {
unsafe {
*(r as *const i32 as *mut i32) += 1;
}
}
```
### Explanation
Casting `&T` to `&mut T` without interior mutability is undefined behavior, as it's a violation of Rust reference aliasing requirements.
-----
Mostly followed the instructions for uplifting a clippy lint described here: https://github.com/rust-lang/rust/pull/99696#pullrequestreview-1134072751
`@rustbot` label: +I-lang-nominated
r? compiler
-----
For Clippy:
changelog: Moves: Uplifted `clippy::cast_ref_to_mut` into rustc
linker: Report linker flavors incompatible with the current target
The linker flavor is checked for target compatibility even if linker is never used (e.g. we are producing a rlib).
If it causes trouble, we can move the check to `link.rs` so it will run if the linker (flavor) is actually used.
And also feature gate explicitly specifying linker flavors for tier 3 targets.
The next step is supporting all the internal linker flavors in user-visible interfaces (command line and json).
Only rewrite valtree-constants to patterns and keep other constants opaque
Now that we can reliably fall back to comparing constants with `PartialEq::eq` to the match scrutinee, we can
1. eagerly try to convert constants to valtrees
2. then deeply convert the valtree to a pattern
3. if the to-valtree conversion failed, create an "opaque constant" pattern.
This PR specifically avoids any behavioral changes or major cleanups. What we can now do as follow ups is
* move the two remaining call sites to `destructure_mir_constant` off that query
* make valtree to pattern conversion infallible
* this needs to be done after careful analysis of the effects. There may be user visible changes from that.
based on https://github.com/rust-lang/rust/pull/111768
We record inlining status for mono items in `MonoItems`, and then
transfer it to `InliningMap`, for later use in
`InliningMap::with_inlining_candidates`.
But we can just compute inlining status directly in
`InliningMap::with_inlining_candidates`, because the mono item is right
there. There's no need to compute it in advance.
This commit changes the code to do that, removing the need for
`MonoItems` and `InliningMap::inlines`. This does result in more calls
to `instantiation_mode` (one per static occurrence) but the performance
effect is negligible.
Rollup of 5 pull requests
Successful merges:
- #111772 (Fix linkage for large binaries on mips64 platforms)
- #111975 (Stop normalizing so many different prefixes)
- #111979 (Respect CARGOFLAGS in bootstrap.py)
- #112089 (Add `--warnings warn` flag to `x.py`)
- #112103 (Bootstrap update to 1.71 beta)
r? `@ghost`
`@rustbot` modify labels: rollup
Add `--warnings warn` flag to `x.py`
So that bootstrap itself can be built with warnings not being treated as errors.
Fixes: https://github.com/rust-lang/rust/issues/76805
r? ```@jyn514```
Respect CARGOFLAGS in bootstrap.py
This makes it possible to pass flags to bootstrap itself, for consistency with std/rustc: 04265621f9/src/bootstrap/builder.rs (L1446-L1447)
Like RUSTFLAGS, this doesn't support CARGOFLAGS_BOOTSTRAP: 6674dcda7a/src/bootstrap/bootstrap.py (L883-L884)
I found this useful recently when I wanted to pass `-Zsparse-registry` to an old checkout of the compiler from before it was stabilized in cargo.
Stop normalizing so many different prefixes
Previously, we would normalize *all* of
- the absolute path to the repository checkout
- the /rustc/$sha for stage1 (if `remap-debuginfo` was enabled)
- the /rustc/$sha for download-rustc
- the sysroot for download-rustc
Now, we consistently only normalize /rustc/FAKE_PREFIX. Not only is this much simpler, but it also avoids ongoing maintenance for download-rustc and makes it much less likely that tests break by accident.
- Change `tests/ui/track-diagnostics/track6.rs` to use a relative path instead of an absolute one. I am not actually sure why `track_caller` works here, but it does seem to work 🤷
- Pass `-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX` to all suites, not just UI. In particular, mir-opt tests emit /rustc/ paths in their output.
r? ```@cjgillot``` since you reviewed https://github.com/rust-lang/rust/pull/110699 - this is the test that it doesn't regress :)
Fix linkage for large binaries on mips64 platforms
This pull request fixes the linkage for large binaries on mips64 platforms by enabling the `xgot` feature in LLVM.
It is well understood that the generated binary will gain a hefty performance penalty where the external symbol jumps now cost at least three instructions each.
Also, this pull request does not address the same issue on the mips32 counterparts (due to being unable to test the changes thoroughly).
Should fix#52108
