Optimize `try_expand_impl_trait_type`
A lot of time was being spent expanding some large `impl Future` types in fuchsia. This PR takes the number of types being visited in one expansion from >3 billion to about a thousand, and eliminates the compile time regression in https://github.com/rust-lang/rust/issues/65147 (in fact, compile times are better than they were before).
Thanks to @Mark-Simulacrum for helping identify the issue and to @matthewjasper for suggesting this change.
Fixes#65147.
r? @matthewjasper,@nikomatsakis
Cleanup librustc mir err codes
Three things are done in this PR:
* Sort error codes
* Uncomment an error code long error explanation (they should **never** be commented)
* Unify explanations
don't assume we can *always* find a return type hint in async fn
In particular, we sometimes cannot if there is an earlier error.
Fixes#65159
r? @cramertj, who reviewed the original PR
Remove last uses of gensyms
Underscore bindings now use unique `SyntaxContext`s to avoid collisions. This was the last use of gensyms in the compiler, so this PR also removes them.
closes#49300
cc #60869
r? @petrochenkov
This commit removes an `Option` check in `BitIter::next()`, avoids
calling `trailing_zeros()` when it's not necessary, and avoids the need
for `enumerate()`. This gives a tiny (0.2%) instruction count win on a
couple of benchmarks.
The commit also adds some comments, which is good because this iteration
code is moderately complex.
add test to for the fix
add descriptive text for the fix
simplified code logics
update descriptive comments
update to cope with the tidyness requirement
merged commit suggestions
Co-Authored-By: varkor <github@varkor.com>
truncated redundant comments
update to cope with tidy-check
Refactor: Rename `db` locals to `diag`
https://github.com/rust-lang/rust/pull/64272 replaced `DiagnosticBuilder` with `Diagnostic` in some places. This PR just renames the db variable from `db` to `diag` where it wasn't renamed.
r? @Mark-Simulacrum
Remove custom `PartialEq` impls for `LocalInternedString`.
This is on-trend with the recent changes simplifying
`LocalInternedString` and reducing its use.
r? @petrochenkov
https://github.com/rust-lang/rust/pull/64272 replaced
`DiagnosticBuilder` with `Diagnostic` in some places. This commit just
renames the DB variable from `db` to `diag` where it wasn't renamed.
Remove an outdated test output file
It was accidentally introduced during some rebase, but it's no longer necessary and `--bless` removes it, but it doesn't fail testing.
syntax: add parser recovery for intersection- / and-patterns `p1 @ p2`
Fixes https://github.com/rust-lang/rust/issues/65400.
The recovery comes in two flavors:
1. We know that `p2` is a binding so we can invert as `p2 @ p1`:
```rust
error: pattern on wrong side of `@`
--> $DIR/intersection-patterns.rs:13:9
|
LL | Some(x) @ y => {}
| -------^^^-
| | |
| | binding on the right, should be to the left
| pattern on the left, should be to the right
| help: switch the order: `y @ Some(x)`
```
2. Otherwise we emit a generic diagnostic for the lack of support for intersection patterns:
```rust
error: left-hand side of `@` must be a binding
--> $DIR/intersection-patterns.rs:23:9
|
LL | Some(x) @ Some(y) => {}
| -------^^^-------
| | |
| | also a pattern
| interpreted as a pattern, not a binding
|
= note: bindings are `x`, `mut x`, `ref x`, and `ref mut x`
```
For more on and-patterns, see e.g. https://docs.microsoft.com/en-us/dotnet/fsharp/language-reference/pattern-matching#and-pattern.
r? @davidtwco
cc @varkor @lzutao
Several changes to the codegen backend organization
* Split functions from values in cg_ssa `BackendTypes`.
* Remove `is_const_integral` function from `ConstMethods`.
* Actually register the invalid monomorphization of intrinsic long diagnostic and remove the `diagnostics` method from `CodegenBackends`, as it was unused.
* Add cg_ssa and cg_utils provided methods to `default_provide`, so codegen backend don't have to do it themself.
std::fmt: reorder docs
This moves the "Formatting Parameters" section up above right after the discussion of named and positional arguments. Then comes the "Syntax" section, summarizing the discussion of format string syntax.
And only *then* we get to "Formatting Traits" -- that section has some *huge* code examples, so it really should not interrupt the discussion of the grammar. Also users are much more likely to come here to learn about the format string grammar than to come here to learn about the `Binary` trait.
