Simplify `LazyAttrTokenStream`
`LazyAttrTokenStream` is an unpleasant type: `Lrc<Box<dyn ToAttrTokenStream>>`. Why does it look like that?
- There are two `ToAttrTokenStream` impls, one for the lazy case, and one for the case where we already have an `AttrTokenStream`.
- The lazy case (`LazyAttrTokenStreamImpl`) is implemented in `rustc_parse`, but `LazyAttrTokenStream` is defined in `rustc_ast`, which does not depend on `rustc_parse`. The use of the trait lets `rustc_ast` implicitly depend on `rustc_parse`. This explains the `dyn`.
- `LazyAttrTokenStream` must have a `size_of` as small as possible, because it's used in many AST nodes. This explains the `Lrc<Box<_>>`, which keeps it to one word. (It's required `Lrc<dyn _>` would be a fat pointer.)
This PR moves `LazyAttrTokenStreamImpl` (and a few other token stream things) from `rustc_parse` to `rustc_ast`. This lets us replace the `ToAttrTokenStream` trait with a two-variant enum and also remove the `Box`, changing `LazyAttrTokenStream` to `Lrc<LazyAttrTokenStreamInner>`. Plus it does a few cleanups.
r? `@petrochenkov`
This commit does the following.
- Changes it from `Lrc<Box<dyn ToAttrTokenStream>>` to
`Lrc<LazyAttrTokenStreamInner>`.
- Reworks `LazyAttrTokenStreamImpl` as `LazyAttrTokenStreamInner`, which
is a two-variant enum.
- Removes the `ToAttrTokenStream` trait and the two impls of it.
The recursion limit must be increased in some crates otherwise rustdoc
aborts.
Introduce Arena::try_alloc_from_iter.
`alloc_from_iter` already collects the iterator for reentrancy. So adding an early exit for a fallible iterator integrates naturally into the code. This avoids the other solution to allocate and dump the allocation.
The previous implementation was inconsistent about transitions that
apply for an init byte. For example, when answering a query, an init
byte could use corresponding init transition. Init byte could also use
uninit transition, but only when the corresponding init transition was
absent. This behaviour was incompatible with DFA union construction.
Define an uninit transition to match an uninit byte only and update
implementation accordingly. To describe that `Tree::uninit` is valid
for any value, build an automaton that accepts any byte value.
Additionally, represent byte ranges uniformly as a pair of integers to
avoid special case for uninit byte.
Replace the \01__gnu_mcount_nc to LLVM intrinsic for additional ARM targets
This is an extension to #113814 which seems to have missed two targets which also need this patch for instrumentation with `-Z instrument-mcount` to work correctly.
For anyone who might stumble over this issue again in the future: As a workaround one can dump the current target configuration using
```
rustc +nightly -Z unstable-options --target armv7-unknown-linux-gnueabihf --print target-spec-json
```
(assuming `armv7-unknown-linux-gnueabihf` is the target to build for) add the line
```
"llvm-mcount-intrinsic": "llvm.arm.gnu.eabi.mcount",
```
and compile with
```
RUSTFLAGS="-Z instrument-mcount -C passes=ee-instrument<post-inline>" cargo +nightly build -Z build-std --target <path to directory with modified target config>/armv7-unknown-linux-gnueabihf.json
```
It might be necessary to set the compiler for cross compiling using something like
```
export TARGET_CC=arm-linux-gnueabihf-gcc
```
PassWrapper: adapt for llvm/llvm-project@d3d856ad84
LLVM 21 moves to making it more explicit what this function call is doing, but nothing has changed behaviorally, so for now we just adjust to using the new name of the function.
`@rustbot` label llvm-main
Enable `reliable_f16_math` on x86
This has been disabled due to an LLVM misoptimization with `powi.f16` [1]. This was fixed upstream and the fix is included in LLVM20, so tests no longer need to be disabled.
`f16` still remains disabled on MinGW due to the ABI issue.
[1]: https://github.com/llvm/llvm-project/issues/98665
try-job: x86_64-gnu
try-job: x86_64-gnu-llvm-19-1
try-job: x86_64-gnu-llvm-20-1
While profiling Zed's dev build I've noticed that while most of the time `upstream_monomorphizations` takes a lot of time in monomorpization_collector, in some cases (e.g. build of `editor` itself)
the rest of monomorphization_collector_graph_walk dominates it. Most of the time is spent in collect_items_rec.
This PR aims to reduce the number of locks taking place; instead of locking output MonoItems once per children of current node, we do so once per *parent*. We also get to reuse locks for mentioned and used items.
While this commit does not reduce Wall time of Zed's build, it does shave off `cargo build -j1` from 43s to 41.5s.
This has been disabled due to an LLVM misoptimization with `powi.f16`
[1]. This was fixed upstream and the fix is included in LLVM20, so tests
no longer need to be disabled.
`f16` still remains disabled on MinGW due to the ABI issue.
[1]: https://github.com/llvm/llvm-project/issues/98665
Extend the alignment check to borrows
The current alignment check does not include checks for creating misaligned references from raw pointers, which is now added in this patch.
When inserting the check we need to be careful with references to field projections (e.g. `&(*ptr).a`), in which case the resulting reference must be aligned according to the field type and not the type of the pointer.
r? `@saethlin`
cc `@RalfJung,` after our discussion in #134424
Most notably, the `FIXME` for suboptimal printing of `use` groups in
`tests/ui/macros/stringify.rs` is fixed. And all other test output
changes result in pretty printed output being closer to the original
formatting in the source code.
Specifically: `TokenCursor`, `TokenTreeCursor`,
`LazyAttrTokenStreamImpl`, `FlatToken`, `make_attr_token_stream`,
`ParserRange`, `NodeRange`. `ParserReplacement`, and `NodeReplacement`.
These are all related to token streams, rather than actual parsing.
This will facilitate the simplifications in the next commit.
only return nested goals for `Certainty::Yes`
Ambiguous `NormalizesTo` goals can otherwise repeatedly add the same nested goals to the parent.
r? ```@compiler-errors```
Implement the internal feature `cfg_target_has_reliable_f16_f128`
Support for `f16` and `f128` is varied across targets, backends, and backend versions. Eventually we would like to reach a point where all backends support these approximately equally, but until then we have to work around some of these nuances of support being observable.
Introduce the `cfg_target_has_reliable_f16_f128` internal feature, which provides the following new configuration gates:
* `cfg(target_has_reliable_f16)`
* `cfg(target_has_reliable_f16_math)`
* `cfg(target_has_reliable_f128)`
* `cfg(target_has_reliable_f128_math)`
`reliable_f16` and `reliable_f128` indicate that basic arithmetic for the type works correctly. The `_math` versions indicate that anything relying on `libm` works correctly, since sometimes this hits a separate class of codegen bugs.
These options match configuration set by the build script at [1]. The logic for LLVM support is duplicated as-is from the same script. There are a few possible updates that will come as a follow up.
The config introduced here is not planned to ever become stable, it is only intended to replace the build scripts for `std` tests and `compiler-builtins` that don't have any way to configure based on the codegen backend.
MCP: https://github.com/rust-lang/compiler-team/issues/866
Closes: https://github.com/rust-lang/compiler-team/issues/866
[1]: 555e1d0386/library/std/build.rs (L84-L186)
---
The second commit makes use of this config to replace `cfg_{f16,f128}{,_math}` in `library/`. I omitted providing a `cfg(bootstrap)` configuration to keep things simpler since the next beta branch is in two weeks.
try-job: aarch64-gnu
try-job: i686-msvc-1
try-job: test-various
try-job: x86_64-gnu
try-job: x86_64-msvc-ext2
Move inline asm check to typeck, properly handle aliases
Pull `InlineAsmCtxt` down to `rustc_hir_typeck`, and instead of using things like `Ty::is_copy`, use the `InferCtxt`-aware methods. To fix https://github.com/rust-lang/trait-system-refactor-initiative/issues/189, we also add a `try_structurally_resolve_*` call to `expr_ty`.
r? lcnr
