simd_fmin/fmax: make semantics and name consistent with scalar intrinsics
This is the SIMD version of https://github.com/rust-lang/rust/pull/153343: change the documented semantics of the SIMD float min/max intrinsics to that of the scalar intrinsics, and also make the name consistent. The overall semantic change this amounts to is that we restrict the non-determinism: the old semantics effectively mean "when one input is an SNaN, the result non-deterministically is a NaN or the other input"; the new semantics say that in this case the other input must be returned. For all other cases, old and new semantics are equivalent. This means all users of these intrinsics that were correct with the old semantics are still correct: the overall set of possible behaviors has become smaller, no new possible behaviors are being added.
In terms of providers of this API:
- Miri, GCC, and cranelift already implement the new semantics, so no changes are needed.
- LLVM is adjusted to use `minimumnum nsz` instead of `minnum`, thus giving us the new semantics.
In terms of consumers of this API:
- Portable SIMD almost certainly wants to match the scalar behavior, so this is strictly a bugfix here.
- Stdarch mostly stopped using the intrinsic, except on nvptx, where arguably the new semantics are closer to what we actually want than the old semantics (https://github.com/rust-lang/stdarch/issues/2056).
Q: Should there be an `f` in the intrinsic name to indicate that it is for floats? E.g., `simd_fminimum_number_nsz`?
Also see https://github.com/rust-lang/rust/issues/153395.
Unimplement unsized_locals
Implements https://github.com/rust-lang/compiler-team/issues/630
Tracking issue here: https://github.com/rust-lang/rust/issues/111942
Note that this just removes the feature, not the implementation, and does not touch `unsized_fn_params`. This is because it is required to support `Box<dyn FnOnce()>: FnOnce()`.
There may be more that should be removed (possibly in follow up prs)
- the `forget_unsized` function and `forget` intrinsic.
- the `unsized_locals` test directory; I've just fixed up the tests for now
- various codegen support for unsized values and allocas
cc ``@JakobDegen`` ``@oli-obk`` ``@Noratrieb`` ``@programmerjake`` ``@bjorn3``
``@rustbot`` label F-unsized_locals
Fixesrust-lang/rust#79409
make abi_unsupported_vector_types a hard error
Fixes https://github.com/rust-lang/rust/issues/116558 by completing the transition; see that issue for context. The lint was introduced with Rust 1.84 and this has been shown in cargo's future breakage reports since Rust 1.85, released 6 weeks ago, and so far we got 0 complaints by users. There's not even a backlink on the tracking issue. We did a [crater run](https://github.com/rust-lang/rust/pull/127731#issuecomment-2286736295) when the lint was originally added and found no breakage. So I don't think we need another crater run now, but I can do one if the team prefers that.
https://github.com/rust-lang/rust/issues/131800 is done, so for most current targets (in particular, all tier 1 and tier 2 targets) we have the information to implement this check (modulo the targets where we don't properly support SIMD vectors yet, see the sub-issues of https://github.com/rust-lang/rust/issues/116558). If a new target gets added in the future, it will default to reject all SIMD vector types until proper information is added, which is the default we want.
This will need approval by for `@rust-lang/lang.` Cc `@workingjubilee` `@veluca93`
try-job: test-various
try-job: armhf-gnu
try-job: dist-i586-gnu-i586-i686-musl
As a rule, the application of `unsafe` to a declaration requires that use-sites
of that declaration also require `unsafe`. For example, a field declared
`unsafe` may only be read in the lexical context of an `unsafe` block.
For nearly all safe traits, the safety obligations of fields are explicitly
discharged when they are mentioned in method definitions. For example,
idiomatically implementing `Clone` (a safe trait) for a type with unsafe fields
will require `unsafe` to clone those fields.
Prior to this commit, `Copy` violated this rule. The trait is marked safe, and
although it has no explicit methods, its implementation permits reads of `Self`.
This commit resolves this by making `Copy` conditionally safe to implement. It
remains safe to implement for ADTs without unsafe fields, but unsafe to
implement for ADTs with unsafe fields.
Tracking: #132922
As part of the "arbitrary self types v2" project, we are going to
replace the current `Receiver` trait with a new mechanism based on a
new, different `Receiver` trait.
This PR renames the old trait to get it out the way. Naming is hard.
Options considered included:
* HardCodedReceiver (because it should only be used for things in the
standard library, and hence is sort-of hard coded)
* LegacyReceiver
* TargetLessReceiver
* OldReceiver
These are all bad names, but fortunately this will be temporary.
Assuming the new mechanism proceeds to stabilization as intended, the
legacy trait will be removed altogether.
Although we expect this trait to be used only in the standard library,
we suspect it may be in use elsehwere, so we're landing this change
separately to identify any surprising breakages.
It's known that this trait is used within the Rust for Linux project; a
patch is in progress to remove their dependency.
This is a part of the arbitrary self types v2 project,
https://github.com/rust-lang/rfcs/pull/3519https://github.com/rust-lang/rust/issues/44874
r? @wesleywiser
- fix for divergence
- fix error message
- fix another cranelift test
- fix some cranelift things
- don't set the NORETURN option for naked asm
- fix use of naked_asm! in doc comment
- fix use of naked_asm! in run-make test
- use `span_bug` in unreachable branch
Subtree sync for rustc_codegen_cranelift
This fixes a crash when compiling the standard library. In addition the Cranelift update fixes all the 128bit int abi incompatibility between cg_clif and cg_llvm.
r? ``@ghost``
``@rustbot`` label +A-codegen +A-cranelift +T-compiler
Oli Scherer