Compute generator saved locals on MIR
Generators are currently type-checked by introducing a `witness` type variable, which is unified with a `GeneratorWitness(captured types)` whose purpose is to ensure that the auto traits correctly migrate from the captured types to the `witness` type. This requires computing the captured types on HIR during type-checking, only to re-do it on MIR later.
This PR proposes to drop the HIR-based computation, and only keep the MIR one. This is done in 3 steps.
1. During type-checking, the `witness` type variable is never unified. This allows to stall all the obligations that depend on it until the end of type-checking. Then, the stalled obligations are marked as successful, and saved into the typeck results for later verification.
2. At type-checking writeback, `witness` is replaced by `GeneratorWitnessMIR(def_id, substs)`. From this point on, all trait selection involving `GeneratorWitnessMIR` will fetch the MIR-computed locals, similar to what opaque types do. There is no lifetime to be preserved here: we consider all the lifetimes appearing in this witness type to be higher-ranked.
3. After borrowck, the stashed obligations are verified against the actually computed types, in the `check_generator_obligations` query. If any obligation was wrongly marked as fulfilled in step 1, it should be reported here.
There are still many issues:
- ~I am not too happy having to filter out some locals from the checked bounds, I think this is MIR building that introduces raw pointers polluting the analysis;~ solved by a check specific to static variables.
- the diagnostics for captured types don't show where they are used/dropped;
- I do not attempt to support chalk.
cc `@eholk` `@jyn514` for the drop-tracking work
r? `@oli-obk` as you warned me of potential unsoundness
solver comments + remove `TyCtxt::evaluate_goal`
from the `RustcContributor::explore` session yesterday.
This also removes `TyCtxt::evaluate_goal` because to canonicalize you have to use an `InferCtxt` anyways at which point we should just always get people to use `evaluate_root_goal`.
r? ``@spastorino``
Replace format flags u32 by enums and bools.
This gets rid of the `flags: u32` field where each bit has a special meaning, and replaces it by simple enums and booleans.
Part of #99012
rustdoc: Collect "rustdoc-reachable" items during early doc link resolution
This pass only needs to know about visibilities, attributes and reexports, so it can be run early, similarly to `compute_effective_visibilities` in rustc.
Results of this pass can be used to prune the list of extern impls early thus improving performance of https://github.com/rust-lang/rust/pull/94857.
rustc_metadata: Fix `encode_attrs`
This function didn't do what the authors intended it to do.
- Due to `move` in the closure `is_public` wasn't captured by mutalbe reference and wasn't used as a cache.
- Due to iterator cloning all the `should_encode_attr` logic run for the second time to calculate `may_have_doc_links`
This PR fixes these issues, and calculates all the needed attribute flags in one go.
(Noticed while implementing https://github.com/rust-lang/rust/pull/107136.)
core: Support variety of atomic widths in width-agnostic functions
Before this change, the following functions and macros were annotated with `#[cfg(target_has_atomic = "8")]` or
`#[cfg(target_has_atomic_load_store = "8")]`:
* `atomic_int`
* `strongest_failure_ordering`
* `atomic_swap`
* `atomic_add`
* `atomic_sub`
* `atomic_compare_exchange`
* `atomic_compare_exchange_weak`
* `atomic_and`
* `atomic_nand`
* `atomic_or`
* `atomic_xor`
* `atomic_max`
* `atomic_min`
* `atomic_umax`
* `atomic_umin`
However, none of those functions and macros actually depend on 8-bit width and they are needed for all atomic widths (16-bit, 32-bit, 64-bit etc.). Some targets might not support 8-bit atomics (i.e. BPF, if we would enable atomic CAS for it).
This change fixes that by removing the `"8"` argument from annotations, which results in accepting the whole variety of widths.
Fixes#106845Fixes#106795
Signed-off-by: Michal Rostecki <vadorovsky@gmail.com>
Sync rustc_codegen_cranelift
For cg_clif itself there have been a couple of bug fixes since the last sync, a Cranelift update and implemented all remaining simd platform intrinsics used by `std::simd`. (`std::arch` still misses a lot though) Most of the diff is from reworking of the cg_clif build system though.
r? `@ghost`
`@rustbot` label +A-codegen +A-cranelift +T-compiler
make `output_filenames` a real query
part of #105462
This may be a perf regression and is not obviously the right way forward. We may store this information in the resolver after freezing it for example.
Rollup of 8 pull requests
Successful merges:
- #106904 (Preserve split DWARF files when building archives.)
- #106971 (Handle diagnostics customization on the fluent side (for one specific diagnostic))
- #106978 (Migrate mir_build's borrow conflicts)
- #107150 (`ty::tls` cleanups)
- #107168 (Use a type-alias-impl-trait in `ObligationForest`)
- #107189 (Encode info for Adt in a single place.)
- #107322 (Custom mir: Add support for some remaining, easy to support constructs)
- #107323 (Disable ConstGoto opt in cleanup blocks)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Disable ConstGoto opt in cleanup blocks
Fixes#107315 .
There is probably a smaller hammer that we could use here, but none that is super obviously correct. We can always revisit this in the future.
Could not add a test because custom mir does not support cleanup blocks. However, did check that the fallible_iterator crate no longer ICEs with the other PR cherry picked.
r? `@tmiasko`
Custom mir: Add support for some remaining, easy to support constructs
Some documentation for previous changes and support for `Deinit`, checked binops, len, and array repetition
r? ```@oli-obk``` or ```@tmiasko```
`ty::tls` cleanups
Pull it out into a separate file, make the conditional compilation more obvious and give the internal functions better names.
Pulled out of #106311
r? cjgillot
Migrate mir_build's borrow conflicts
This also changes the error message slightly, for two reasons:
- I'm not a fan of saying "value borrowed, by `x`, here"
- it simplifies the error implementation significantly.
Move format_args!() into AST (and expand it during AST lowering)
Implements https://github.com/rust-lang/compiler-team/issues/541
This moves FormatArgs from rustc_builtin_macros to rustc_ast_lowering. For now, the end result is the same. But this allows for future changes to do smarter things with format_args!(). It also allows Clippy to directly access the ast::FormatArgs, making things a lot easier.
This change turns the format args types into lang items. The builtin macro used to refer to them by their path. After this change, the path is no longer relevant, making it easier to make changes in `core`.
This updates clippy to use the new language items, but this doesn't yet make clippy use the ast::FormatArgs structure that's now available. That should be done after this is merged.
