Rollup of 7 pull requests
Successful merges:
- #109395 (Fix issue when there are multiple candidates for edit_distance_with_substrings)
- #109755 (Implement support for `GeneratorWitnessMIR` in new solver)
- #109782 (Don't leave a comma at the start of argument list when removing arguments)
- #109977 (rustdoc: avoid including line numbers in Google SERP snippets)
- #109980 (Derive String's PartialEq implementation)
- #109984 (Remove f32 & f64 from MemDecoder/MemEncoder)
- #110004 (add `dont_check_failure_status` option in the compiler test)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Make `rustc_query_system` take `QueryConfig` by instance.
This allows for easy switching between virtual tables and specialized instances for queries. It also has the benefit of less turbofish. `QueryStorage` has also been merged with `QueryCache`.
Split out from https://github.com/rust-lang/rust/pull/107937.
r? `@cjgillot`
Convert all the crates that have had their diagnostic migration
completed (except save_analysis because that will be deleted soon and
apfloat because of the licensing problem).
This may introduce additional mono _but_ may help const fold things
better and especially may help not constructing a `QueryVTable` anymore
which is cheap but not free.
Allow to feed a value in another query's cache
Restricted version of https://github.com/rust-lang/rust/pull/96840
A query can create new definitions.
If those definitions are created after HIR lowering, they do not appear in the initial HIR map, and information for them cannot be provided in the normal pull-based way.
In order to make those definitions useful, we allow to feed values as query results for the newly created definition.
The API is as follows:
```rust
let feed = tcx.create_def(<parent def id>, <DefPathData>);
// `feed` is a TyCtxtFeed<'tcx>.
// Access the created definition.
let def_id: LocalDefId = feed.def_id;
// Assign `my_query(def_id) := my_value`.
feed.my_query(my_value).
```
This PR keeps the consistency checks introduced by https://github.com/rust-lang/rust/pull/96840, even if they are not reachable. This allows to extend the behaviour later without forgetting them.
cc `@oli-obk` `@spastorino`
Unsupported query error now specifies if its unsupported for local or external crate
Fixes#101666.
I had to move `keys.rs` from `rustc_query_impl` to `rustc_middle`. I don't know if that is problematic. I couldn't think of any other way to get the needed information inside `rustc_middle`.
r? ```@jyn514```
Initial pass at expr/abstract const/s
Address comments
Switch to using a list instead of &[ty::Const], rm `AbstractConst`
Remove try_unify_abstract_consts
Update comments
Add edits
Recurse more
More edits
Prevent equating associated consts
Move failing test to ui
Changes this test from incremental to ui, and mark it as failing and a known bug.
Does not cause the compiler to ICE, so should be ok.
indirect immutable freeze by-value function parameters.
Right now, `rustc` only examines function signatures and the platform ABI when
determining the LLVM attributes to apply to parameters. This results in missed
optimizations, because there are some attributes that can be determined via
analysis of the MIR making up the function body. In particular, `readonly`
could be applied to most indirectly-passed by-value function arguments
(specifically, those that are freeze and are observed not to be mutated), but
it currently is not.
This patch introduces the machinery that allows `rustc` to determine those
attributes. It consists of a query, `deduced_param_attrs`, that, when
evaluated, analyzes the MIR of the function to determine supplementary
attributes. The results of this query for each function are written into the
crate metadata so that the deduced parameter attributes can be applied to
cross-crate functions. In this patch, we simply check the parameter for
mutations to determine whether the `readonly` attribute should be applied to
parameters that are indirect immutable freeze by-value. More attributes could
conceivably be deduced in the future: `nocapture` and `noalias` come to mind.
Adding `readonly` to indirect function parameters where applicable enables some
potential optimizations in LLVM that are discussed in [issue 103103] and [PR
103070] around avoiding stack-to-stack memory copies that appear in functions
like `core::fmt::Write::write_fmt` and `core::panicking::assert_failed`. These
functions pass a large structure unchanged by value to a subfunction that also
doesn't mutate it. Since the structure in this case is passed as an indirect
parameter, it's a pointer from LLVM's perspective. As a result, the
intermediate copy of the structure that our codegen emits could be optimized
away by LLVM's MemCpyOptimizer if it knew that the pointer is `readonly
nocapture noalias` in both the caller and callee. We already pass `nocapture
noalias`, but we're missing `readonly`, as we can't determine whether a
by-value parameter is mutated by examining the signature in Rust. I didn't have
much success with having LLVM infer the `readonly` attribute, even with fat
LTO; it seems that deducing it at the MIR level is necessary.
No large benefits should be expected from this optimization *now*; LLVM needs
some changes (discussed in [PR 103070]) to more aggressively use the `noalias
nocapture readonly` combination in its alias analysis. I have some LLVM patches
for these optimizations and have had them looked over. With all the patches
applied locally, I enabled LLVM to remove all the `memcpy`s from the following
code:
```rust
fn main() {
println!("Hello {}", 3);
}
```
which is a significant codegen improvement over the status quo. I expect that
if this optimization kicks in in multiple places even for such a simple
program, then it will apply to Rust code all over the place.
[issue 103103]: https://github.com/rust-lang/rust/issues/103103
[PR 103070]: https://github.com/rust-lang/rust/pull/103070
Queries can provide an arbitrary expression for their description and
their caching behavior. Before, these expressions where stored in a
`rustc_query_description` macro emitted by the `rustc_queries` macro,
and then used in `rustc_query_impl` to fill out the methods for the
`QueryDescription` trait.
Instead, we now emit two new modules from `rustc_queries` containing the
functions with the expressions. `rustc_query_impl` calls these functions
now instead of invoking the macro.
Since we are now defining some of the functions in
`rustc_middle::query`, we now need all the imports for the key types
there as well.
