Add a special case for align_offset /w stride != 1
This generalizes the previous `stride == 1` special case to apply to any
situation where the requested alignment is divisible by the stride. This
in turn allows the test case from #98809 produce ideal assembly, along
the lines of:
leaq 15(%rdi), %rax
andq $-16, %rax
This also produces pretty high quality code for situations where the
alignment of the input pointer isn’t known:
pub unsafe fn ptr_u32(slice: *const u32) -> *const u32 {
slice.offset(slice.align_offset(16) as isize)
}
// =>
movl %edi, %eax
andl $3, %eax
leaq 15(%rdi), %rcx
andq $-16, %rcx
subq %rdi, %rcx
shrq $2, %rcx
negq %rax
sbbq %rax, %rax
orq %rcx, %rax
leaq (%rdi,%rax,4), %rax
Here LLVM is smart enough to replace the `usize::MAX` special case with
a branch-less bitwise-OR approach, where the mask is constructed using
the neg and sbb instructions. This appears to work across various
architectures I’ve tried.
This change ends up introducing more branches and code in situations
where there is less knowledge of the arguments. For example when the
requested alignment is entirely unknown. This use-case was never really
a focus of this function, so I’m not particularly worried, especially
since llvm-mca is saying that the new code is still appreciably faster,
despite all the new branching.
Fixes#98809.
Sadly, this does not help with #72356.
This generalizes the previous `stride == 1` special case to apply to any
situation where the requested alignment is divisible by the stride. This
in turn allows the test case from #98809 produce ideal assembly, along
the lines of:
leaq 15(%rdi), %rax
andq $-16, %rax
This also produces pretty high quality code for situations where the
alignment of the input pointer isn’t known:
pub unsafe fn ptr_u32(slice: *const u32) -> *const u32 {
slice.offset(slice.align_offset(16) as isize)
}
// =>
movl %edi, %eax
andl $3, %eax
leaq 15(%rdi), %rcx
andq $-16, %rcx
subq %rdi, %rcx
shrq $2, %rcx
negq %rax
sbbq %rax, %rax
orq %rcx, %rax
leaq (%rdi,%rax,4), %rax
Here LLVM is smart enough to replace the `usize::MAX` special case with
a branch-less bitwise-OR approach, where the mask is constructed using
the neg and sbb instructions. This appears to work across various
architectures I’ve tried.
This change ends up introducing more branches and code in situations
where there is less knowledge of the arguments. For example when the
requested alignment is entirely unknown. This use-case was never really
a focus of this function, so I’m not particularly worried, especially
since llvm-mca is saying that the new code is still appreciably faster,
despite all the new branching.
Fixes#98809.
Sadly, this does not help with #72356.
Fix flakyness of GUI tests
Fixes#98163.
All flaky tests seemed to be linked to the search. Since the search JS is loaded when we focus the search input, I think it's possible that we enter faster than the JS is actually loaded. The solution for that would be to do it in two steps: first we write into the search input (`browser-ui-test` adds a small sleep time after such commands) and then we press enter to be sure that it wasn't missed.
cc `@JohnTitor`
r? `@Dylan-DPC`
Borrow Vec<T, A> as [T]
Hello all,
When `Vec` was parametrized with `A`, the `Borrow` impls were omitted and currently `Vec<T, A>` can't be borrowed as `[T]`. This PR fixes that.
This was probably missed, because the `Borrow` impls are in a different file - `src/alloc/slice.rs`.
We briefly discussed this here: https://github.com/rust-lang/wg-allocators/issues/96 and I was told to go ahead and make a PR :)
I tested this by building the toolchain and building my code that needed the `Borrow` impl against it, but let me know if I should add any tests to this PR.
Revert "Highlight conflicting param-env candidates"
This reverts #98794, commit 08135254dc.
Seems to have caused an incremental compilation bug. The root cause of the incr comp bug is somewhat unrelated but is triggered by this PR, so I don't feel comfortable with having this PR in the codebase until it can be investigated further. Fixes#99233.
[rustdoc-json] JSON no longer inlines
Fixes#98007.
Fixes#96161.
Fixes https://github.com/rust-lang/rust/issues/83057.
Fixes https://github.com/rust-lang/rust/issues/83720.
I took over #93518 and applied the comments and added more tests.
There was one thing missing (which is in the second commit): if a non-exported item was used in a public API but not reexported, it was still missing.
cc `@CraftSpider` `@Urgau` `@Enselic`
r? `@notriddle`
interpret/visitor: support visiting with a PlaceTy
Finally we can visit a `PlaceTy` in a way that will only do `force_allocation` when needed ti visit a field. :)
r? `@oli-obk`
migrate some of `rustc_passes::check_attr`'s diagnostics and derive improvements
- Implements `IntoDiagnosticArg` for `char` using its `Debug` implementation and introduces a macro for those types which just delegate the implementation to `ToString`.
- Apply the `#[rustc_lint_diagnostics]` attribute to `LintDiagnosticBuilder::build` so that diagnostic migration lints will trigger for it - some diagnostics in `rustc_privacy` need updated after this since the lints apply to that crate.
- Add support for `MultiSpan` with any of the attributes that work on a `Span` in the diagnostic derive (`SessionDiagnostic` + `LintDiagnostic`). Requires that diagnostic logic generated for these attributes are emitted in the by-move block rather than the by-ref block that they would normally have been generated in.
- Both diagnostic and subdiagnostic derives were missing the ability to add warnings to diagnostics - this is made more difficult by the `warn` attribute already existing, so this name being unavailable for the derives to use. `#[warn_]` is used instead, which requires special-casing so that `{span_,}warn` is called instead of `{span_,}warn_`.
- Migrate half of the `rustc_passes::check_attr` diagnostics to using diagnostic derives and being translatable. I got tired after a while. I modified some diagnostic output for consistency while doing this, nothing too crazy.
r? `@compiler-errors`
Allow destructuring opaque types in their defining scopes
fixes#96572
Before this PR, the following code snippet failed with an incomprehensible error, and similar code just ICEd in mir borrowck.
```rust
type T = impl Copy;
let foo: T = (1u32, 2u32);
let (a, b) = foo;
```
The problem was that the last line created MIR projections of the form `foo.0` and `foo.1`, but `foo`'s type is `T`, which doesn't have fields (only its hidden type does). But the pattern supplies enough type information (a tuple of two different inference types) to bind a hidden type.
Update highlight.js
changelog: none
With [highlight.js v11.6.0](https://github.com/highlightjs/highlight.js/releases/tag/11.6.0), the lint list can finally update from `9.5.0`. No more EOL warning in console! 😄
I also made it switch to the `github-dark` theme when using `coal`, instead of just always using the normal github light theme.
r? `@xFrednet`
Fix ICE in `named_arguments_used_positionally` lint
Fixes#99261Fixes#99289Fixes#99284Fixes#99273Fixes#99297Fixes#99271
This match pattern:
```
FormatSpec { width: Count::CountIsName(s, _), .. }
| FormatSpec { precision: Count::CountIsName(s, _), .. }
```
does not account for when both `width` and `precision` are both `Count::CountIsName`, so split the check for these two fields into two separate `if let`.
Also, remove any future potential for ICEs by removing the index operator altogether.
---
It is still suspicious that this indexing was broken and caused the ICE, as opposed to just causing a spurious lint message.
cc `@PrestonFrom,` who may be familiar with this code because of implementing the lint this touches, perhaps you'd like to look into why named arguments in `FormatSpec.precision` seem to have indices that don't correspond to a span in `Context.arg_spans`?
Edit: Opened #99265 to track a (related?) incorrect argument indexing issue.
Add Output = expected type trait obligation for known binary operators
This PR is a follow-on to #94034 that addresses #96442. That is, after replacing the trait-suggestion logic in `op.rs` with a more generic path that analyzes a general set of `Obligation`s, then we lost some specificity in the suggestions where the bounds on the associated type `Output=` would not get suggested.
This PR fixes this issue by changing `FnCtxt::construct_obligation_for_trait` to include a new `ProjectionPredicate` obligation for binary operators that obliges that `Output` is the same as the expected type of the expression. Additionally, to get the expected type of the expression, this PR threads the `Expectation<'tcx>` structure throughout several functions.
See src/test/ui/generic-associated-types/missing-bounds.stderr for an example of how this works.
One side effect of this change is it causes type-check failures with binops to include additional information. Specifically, many now say
```
error: type mismatch resolving `<Lhs as TheBinop>::Output == ExpectedTy`
```
It's up for discussion whether this added context is worth it to the user.
r? `@estebank`
Stabilize `core::ffi::CStr`, `alloc::ffi::CString`, and friends
Stabilize the `core_c_str` and `alloc_c_string` feature gates.
Change `std::ffi` to re-export these types rather than creating type
aliases, since they now have matching stability.
Revert "Work around invalid DWARF bugs for fat LTO"
Since September, the toolchain has not been generating reliable DWARF
information for static variables when LTO is on. This has affected
projects in the embedded space where the use of LTO is typical. In our
case, it has kept us from bumping past the 2021-09-22 nightly toolchain
lest our debugger break. This has been a pretty dramatic regression for
people using debuggers and static variables. See #90357 for more info
and a repro case.
This commit is a mechanical revert of
d5de680e20 from PR #89041, which caused
the issue. (Note on that PR that the commit's author has requested it be
reverted.)
I have locally verified that this fixes#90357 by restoring the
functionality of both the repro case I posted on that bug, and debugger
behavior on real programs. There do not appear to be test cases for this
in the toolchain; if I've missed them, point me at 'em and I'll update
them.
Mark stabilized intrinsics with `rustc_allowed_through_unstable_modules`
Fixes#99286
PR #95956 accidentally made these intrinsics unstable when
accessed through the unstable path segment 'std::intrinsics'
