`ResultsCursor` currently owns its `Results`. But sometimes the
`Results` is needed again afterwards. So there is
`ResultsCursor::into_results` for extracting the `Results`, which leads
to some awkwardness.
This commit adds `ResultsHandle`, a `Cow`-like type that can either
borrow or own a a `Results`. `ResultsCursor` now uses it. This is good
because some `ResultsCursor`s really want to own their `Results`, while
others just want to borrow it.
We end with with a few more lines of code, but get some nice cleanups.
- `ResultsCursor::into_results` and `Formatter::into_results` are
removed.
- `write_graphviz_results` now just borrows a `Results`, instead of the
awkward "take ownership of a `Results` and then return it unchanged"
pattern.
This reinstates the cursor flexibility that was lost in #118230 -- which
removed the old `ResultsRefCursor` and `ResultsCloneCursor` types -- but
in a much simpler way. Hooray!
In `MaybeRequiresStorage::apply_before_statement_effect`, call
`transfer_function` directly, as is already done in
`MaybeRequiresStorage::apply_before_terminator_effect`. This makes it clear
that the operation doesn't rely on the `MaybeBorrowedLocals` results.
Foreword
========
Let us begin the journey to rediscover what the `//@ pretty-expanded`
directive does, brave traveller --
"My good friend, [..] when I wrote that passage, God and I knew what
it meant. It is possible that God knows it still; but as for me, I
have totally forgotten."
-- Johann Paul Friedrich Richter, 1826
We must retrace the steps of those before us, for history shall guide us
in the present and inform us of the future.
The Past
========
Originally there was some effort to introduce more test coverage for `-Z
unpretty=expanded` (in 2015 this was called `--pretty=expanded`). In
[Make it an error to not declare used features #23598][pr-23598], there
was a flip from `//@ no-pretty-expanded` (opt-out of `-Z
unpretty=expanded` test) to `//@ pretty-expanded` (opt-in to `-Z
unpretty=expanded` test). This was needed because back then the
dedicated `tests/pretty` ("pretty") test suite did not existed, and the
pretty tests were grouped together under `run-pass` tests (I believe
`ui` test suite didn't exist back then either). Unfortunately, in this
process the replacement `//@ pretty-expanded` directives contained a
`FIXME #23616` linking to [There are very few tests for `-Z unpretty`
expansion #23616][issue-23616]. But this was arguably backwards and
somewhat misleading, as noted in
<https://github.com/rust-lang/rust/issues/23616#issuecomment-484999901>:
The attribute is off by default and things just work if you don't
test it, people have not been adding the `pretty-expanded`
annotation to new tests even if it would work.
Which basically renders this useless.
The Present
===========
As of Nov 2024, we have a dedicated `pretty` test suite, and some time
over the years the split between `run-pass` into `ui` and `pretty` test
suites caused all of the `//@ pretty-expanded` in `ui` tests to do
absolutely nothing -- the compiletest logic for `pretty-expanded` only
triggered in the *pretty* test suite, but none of the pretty tests use
it. Oops.
The Future
==========
Nobody remembers this, nobody uses this, it's misleading in ui tests.
Let's get rid of this directive altogether.
[pr-23598]: https://github.com/rust-lang/rust/pull/23598
[issue-23616]: https://github.com/rust-lang/rust/issues/23616
The test was checking for two `ptr` arguments by matching commas (or
non-commas), however after
https://github.com/llvm/llvm-project/pull/117104 LLVM adds an
`initializes((0, 16))` attribute, which includes a comma.
So instead, we make the test check for two LLVM values, i.e. something
prefixed by %.
(See also https://crbug.com/380707238)
Reduce integer `Display` implementation size
I was thinking about #128204 and how we could reduce the size of the code and just realized that we didn't need the `_fmt` method to be implemented on signed integers, which in turns allow to simplify greatly the macro call.
r? `@workingjubilee`
Rollup of 8 pull requests
Successful merges:
- #131523 (Fix asm goto with outputs and move it to a separate feature gate)
- #131664 (Support input/output in vector registers of s390x inline assembly (under asm_experimental_reg feature))
- #132432 (Add a test to verify that libstd doesn't use protected symbols)
- #132502 (Document possibility to set core features in example config.toml)
- #132529 (ci(triagebot): add more top-level files to A-meta)
- #132533 (Add BorrowedBuf::into_filled{,_mut} methods to allow returning buffer with original lifetime)
- #132803 (Fix broken url)
- #132982 (alloc: fix `Allocator` method names in `alloc` free function docs)
r? `@ghost`
`@rustbot` modify labels: rollup
I implemented that with a separate trait and not within `SliceIndex`, because doing that via `SliceIndex` requires adding support for range types that are (almost) always overlapping e.g. `RangeFrom`, and also adding fake support code for `impl SliceIndex<str>`.
An inconvenience that I ran into was that slice indexing takes the index by value, but I only have it by reference. I could change slice indexing to take by ref, but this is pretty much the hottest code ever so I'm afraid to touch it. Instead I added a requirement for `Clone` (which all index types implement anyway) and cloned. This is an internal requirement the user won't see and the clone should always be optimized away.
I also implemented `Clone`, `PartialEq` and `Eq` for the error type, since I noticed it does not do that when writing the tests and other errors in std seem to implement them. I didn't implement `Copy` because maybe we will want to put something non-`Copy` there.
alloc: fix `Allocator` method names in `alloc` free function docs
It looks like these got renamed in 9274b37d99 but the docs never updated.
I couldn't find any history for `Allocator::realloc`. The `grow` API is not 1:1 (e.g., it returns a result), so this may not be the correct change - let me know and I can change the method or even remove this entirely.
ci(triagebot): add more top-level files to A-meta
It didn't exist so I changed it with its new versions: `COPYRIGHT`, `LICENSE-APACHE` and `LICENSE-MIT`
I also added some other files I found appropriate under the related label.
Support input/output in vector registers of s390x inline assembly (under asm_experimental_reg feature)
This extends currently clobber-only vector registers (`vreg`) support to allow passing `#[repr(simd)]` types, floats (f32/f64/f128), and integers (i32/i64/i128) as input/output.
This is unstable and gated under new `#![feature(asm_experimental_reg)]` (tracking issue: https://github.com/rust-lang/rust/issues/133416). If the feature is not enabled, only clober is supported as before.
| Architecture | Register class | Target feature | Allowed types |
| ------------ | -------------- | -------------- | -------------- |
| s390x | `vreg` | `vector` | `i32`, `f32`, `i64`, `f64`, `i128`, `f128`, `i8x16`, `i16x8`, `i32x4`, `i64x2`, `f32x4`, `f64x2` |
This matches the list of types that are supported by the vector registers in LLVM:
https://github.com/llvm/llvm-project/blob/llvmorg-19.1.0/llvm/lib/Target/SystemZ/SystemZRegisterInfo.td#L301-L313
In addition to `core::simd` types and floats listed above, custom `#[repr(simd)]` types of the same size and type are also allowed. All allowed types other than i32/f32/i64/f64/i128, and relevant target features are currently unstable.
Currently there is no SIMD type for s390x in `core::arch`, but this is tracked in https://github.com/rust-lang/rust/issues/130869.
cc https://github.com/rust-lang/rust/issues/130869 about vector facility support in s390x
cc https://github.com/rust-lang/rust/issues/125398 & https://github.com/rust-lang/rust/issues/116909 about f128 support in asm
`@rustbot` label +O-SystemZ +A-inline-assembly
Fix asm goto with outputs and move it to a separate feature gate
Tracking issue: #119364
This PR addresses 3 aspects of asm goto with outputs:
* Codegen is fixed. My initial implementation has an oversight which cause the output to be only stored in fallthrough path, but not in label blocks.
* Outputs can now be used with `options(noreturn)` if a label block is given.
* All of this is moved to a new feature gate, because we likely want to stabilise `asm_goto` before asm goto with outputs.
`@rustbot` labels: +A-inline-assembly +F-asm
There is a not-very-useful layering in the lexer, where
`TokenTreesReader` contains a `StringReader`. This commit combines them
and names the result `Lexer`, which is a more obvious name for it.
The methods of `Lexer` are now split across `mod.rs` and `tokentrees.rs`
which isn't ideal, but it doesn't seem worth moving a bunch of code to
avoid it.
