Pattern Migration 2024: fix incorrect messages/suggestions when errors arise in macro expansions
See the diff between the two commits for how this affected the error message and suggestion. In order to decide how to format those, the pattern migration diagnostic keeps track of which parts of the user's pattern cause problems in Edition 2024. However, it neglected to do some of this bookkeeping when pointing to macro expansion sites. This fixes that.
Do not ICE on default_field_value const with lifetimes
`#![feature(default_field_values)]` uses a `const` body that should be treated as inline `const`s, but is actually being detected otherwise. This is similar to the situation in #78174, so we take the same solution: we check if the const actually comes from a field, and if it does, we use that logic to get the appropriate lifetimes and not ICE during borrowck.
Fix#135649.
improve cold_path()
#120370 added a new instrinsic `cold_path()` and used it to fix `likely` and `unlikely`
However, in order to limit scope, the information about cold code paths is only used in 2-target switch instructions. This is sufficient for `likely` and `unlikely`, but limits usefulness of `cold_path` for idiomatic rust. For example, code like this:
```
if let Some(x) = y { ... }
```
may generate 3-target switch:
```
switch y.discriminator:
0 => true branch
1 = > false branch
_ => unreachable
```
and therefore marking a branch as cold will have no effect.
This PR improves `cold_path()` to work with arbitrary switch instructions.
Note that for 2-target switches, we can use `llvm.expect`, but for multiple targets we need to manually emit branch weights. I checked Clang and it also emits weights in this situation. The Clang's weight calculation is more complex that this PR, which I believe is mainly because `switch` in `C/C++` can have multiple cases going to the same target.
Move methods from `Map` to `TyCtxt`, part 2.
Continuing the work started in #136466.
Every method gains a `hir_` prefix, though for the ones that already have a `par_` or `try_par_` prefix I added the `hir_` after that.
r? Zalathar
It's currently lacking comments. This commit adds some, which is useful
because there are some methods with non-obvious behaviour.
The commit also renames two things:
- `patch_map` becomes `term_patch_map`, because it's only about
terminators.
- `is_patched` becomes `is_term_patched`, for the same reason.
(I would guess that originally `MirPatch` only handled terminators, and
then over time it expanded to allow other modifications, but these names
weren't updated.)
Instead of `expand_statements`. This makes the code shorter and
consistent with other MIR transform passes.
The tests require updating because there is a slight change in
MIR output:
- the old code replaced the original statement with twelve new
statements.
- the new code inserts converts the original statement to a `nop` and
then insert twelve new statements in front of it.
I.e. we now end up with an extra `nop`, which doesn't matter at all.
Continuing the work started in #136466.
Every method gains a `hir_` prefix, though for the ones that already
have a `par_` or `try_par_` prefix I added the `hir_` after that.
Rollup of 7 pull requests
Successful merges:
- #137095 (Replace some u64 hashes with Hash64)
- #137100 (HIR analysis: Remove unnecessary abstraction over list of clauses)
- #137105 (Restrict DerefPure for Cow<T> impl to T = impl Clone, [impl Clone], str.)
- #137120 (Enable `relative-path-include-bytes-132203` rustdoc-ui test on Windows)
- #137125 (Re-add missing empty lines in the releases notes)
- #137145 (use add-core-stubs / minicore for a few more tests)
- #137149 (Remove SSE ABI from i586-pc-windows-msvc)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove SSE ABI from i586-pc-windows-msvc
As an i586 target, it should not have SSE. This caused the following warning to be emitted:
```
warning: target feature `sse2` must be enabled to ensure that the ABI of the current target can be implemented correctly
|
= note: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #116344 <https://github.com/rust-lang/rust/issues/116344>
warning: 1 warning emitted
```
see #116344.
r? RalfJung
HIR analysis: Remove unnecessary abstraction over list of clauses
`rustc_hir_analysis::bounds::Bounds` with its methods is nowadays a paper-thin wrapper around `Vec<(Clause, Span)>`s and `Vec::push` essentially.
Its existence slightly annoyed me (and I keep opening its corresp. file instead of the identically named `bounds.rs` in `hir_ty_lowering/` that I actually want most of the time :P).
Opening to check if you agree with inlining it.
r? compiler-errors or reassign
Replace some u64 hashes with Hash64
I introduced the Hash64 and Hash128 types in https://github.com/rust-lang/rust/pull/110083, essentially as a mechanism to prevent hashes from landing in our leb128 encoding paths. If you just have a u64 or u128 field in a struct then derive Encodable/Decodable, that number gets leb128 encoding. So if you need to store a hash or some other value which behaves very close to a hash, don't store it as a u64.
This reverts part of https://github.com/rust-lang/rust/pull/117603, which turned an encoded Hash64 into a u64.
Based on https://github.com/rust-lang/rust/pull/110083, I don't expect this to be perf-sensitive on its own, though I expect that it may help stabilize some of the small rmeta size fluctuations we currently see in perf reports.
Fix const items not being allowed to be called `r#move` or `r#static`
Because of an ambiguity with const closures, the parser needs to ensure that for a const item, the `const` keyword isn't followed by a `move` or `static` keyword, as that would indicate a const closure:
```rust
fn main() {
const move // ...
}
```
This check did not take raw identifiers into account, therefore being unable to distinguish between `const move` and `const r#move`. The latter is obviously not a const closure, so it should be allowed as a const item.
This fixes the check in the parser to only treat `const ...` as a const closure if it's followed by the *proper keyword*, and not a raw identifier.
Additionally, this adds a large test that tests for all raw identifiers in all kinds of positions, including `const`, to prevent issues like this one from occurring again.
fixes#137128
Pattern Migration 2024: clean up and comment
This follows up on #136577 by moving the pattern migration logic to its own module, removing a bit of unnecessary complexity, and adding comments. Since there's quite a bit of pattern migration logic now (and potentially more in #136496), I think it makes sense to keep it separate from THIR construction, at least as much as is convenient.
r? ``@Nadrieril``
Overhaul `rustc_middle::limits`
In particular, to make `pattern_complexity` work more like other limits, which then enables some other simplifications.
r? ``@Nadrieril``
Start removing `rustc_middle::hir::map::Map`
`rustc_middle::hir::map::Map` is now just a low-value wrapper around `TyCtxt`. This PR starts removing it.
r? `@cjgillot`
First of all, note that `Map` has three different relevant meanings.
- The `intravisit::Map` trait.
- The `map::Map` struct.
- The `NestedFilter::Map` associated type.
The `intravisit::Map` trait is impl'd twice.
- For `!`, where the methods are all unreachable.
- For `map::Map`, which gets HIR stuff from the `TyCtxt`.
As part of getting rid of `map::Map`, this commit changes `impl
intravisit::Map for map::Map` to `impl intravisit::Map for TyCtxt`. It's
fairly straightforward except various things are renamed, because the
existing names would no longer have made sense.
- `trait intravisit::Map` becomes `trait intravisit::HirTyCtxt`, so named
because it gets some HIR stuff from a `TyCtxt`.
- `NestedFilter::Map` assoc type becomes `NestedFilter::MaybeTyCtxt`,
because it's always `!` or `TyCtxt`.
- `Visitor::nested_visit_map` becomes `Visitor::maybe_tcx`.
I deliberately made the new trait and associated type names different to
avoid the old `type Map: Map` situation, which I found confusing. We now
have `type MaybeTyCtxt: HirTyCtxt`.
The end goal is to eliminate `Map` altogether.
I added a `hir_` prefix to all of them, that seemed simplest. The
exceptions are `module_items` which became `hir_module_free_items` because
there was already a `hir_module_items`, and `items` which became
`hir_free_items` for consistency with `hir_module_free_items`.
It's always good to make `rustc_middle` smaller. `rustc_interface` is
the best destination, because it's the only crate that calls
`get_recursive_limit`.
