MIR-borrowck: moves of prefixes invalidate uses too
I overlooked the fact that when we check if a path is moved, we need to check for interference between the (shallow) prefixes and the use in question.
~~Long term, we may want to revise how this computation is done. For example, it might be better to represent the set of invalidated prefixes in the dataflow computation (the `maybe_uninitialized` dataflow), and thus avoid one of the loops in the code here.~~
* Update: I was wrong in my original recollection of the dataflow code, which actually does the right thing, in terms of precisely tracking substructure initialization and movement.
Fix#44833
----
Update: The initial version of this PR's description (and the code as well) erroneously focused on supporting prefixes. ~~But the two main cases of interest are: 1. the *shallow* prefixes, and 2. the deref-free prefix built off a local (if the lvalue is indeed built off a local)~~
Update 2: The main cases of interest are in fact: 1. the nearest prefix with a MovePath, and 2. the suffixes.
Extend mir dump to dump each region
Building on #44878, implement the feature discussed in #44872.
Through discussions on the WG-nll-gitter, @nikomatsakis and I decided to implement this by extending `dump_mir` and all functions that it calls to take a callback of signature `FnMut(PassWhere, &mut Write) -> io::Result<()>` where `PassWhere` is an enum that represents possible locations that we may want to print out extra data in the process of dumping the MIR.
I'm not particularly wedded to the name `PassWhere`, but I felt that simply calling the enum `Where` wasn't the right thing to name it.
This work depends strongly on #44878, and should be rebased on the final version of that tree, whatever that may be.
Fix PEP8 style issues in bootstrap code
This fixes PEP8 style issues (other than line-length) in the bootstrap Python code.
The most important fix is in the `set` function where the code was indented with 6 spaces instead of 4.
let rustdoc print the crate version into docs
This PR adds a new unstable flag to rustdoc, `--crate-version`, which when present will add a new entry to the sidebar of the root module, printing the given version number:
Closes#24336
(The WIP status is because i don't want to merge this until i can get the std docs to use it, which i need help from rustbuild people to make sure i get right.)
Optimize comparison functions of Iterator
Replaced matching on tuples which led to less performant code generation. Testing on microbenchmarks consistently showed ~1.35x improvement in performance on my machine.
Fixes#44729.
MIR borrowck: print lvalues in error messages in the same way that the AST borrowck
Fix#44974
- Print fields with `.name` rather than `.<num>`
- Autoderef values if followed by a field or an index
- Output `[..]` when borrowing inside a slice
(There are other tests that this PR also improves, but were not
completely synchronized. I chose to wait until later to pull those
into the `revisions: ast mir` testing pattern; later being either when
they *are* synchronized, or in some PR where we migrate all borrowck
tests, regardless of whether MIR-borrowck is "finished" for them or
not.)
Fix#44833 (a very specific instance of a very broad bug).
In `check_if_path_is_moved(L)`, check nearest prefix of L with
MovePath, and suffixes of L with MovePaths.
Over the course of review, ariel pointed out a number of issues that
led to this version of the commit:
1. Looking solely at supporting prefixes does not suffice: it
overlooks checking if the path was ever actually initialized in the
first place. So you need to be willing to consider non-supporting
prefixes. Once you are looking at all prefixes, you *could* just
look at the local that forms the base of the projection, but to
handle partial initialization (which still needs to be formally
specified), this code instead looks at the nearest prefix of L that
has an associated MovePath (which, in the limit, will end up being
a local).
2. You also need to consider the suffixes of the given Lvalue, due to
how dataflow is representing partial moves of individual fields out
of struct values.
3. (There was originally a third search, but ariel pointed out that
the first and third could be folded into one.)
Also includes some drive-by refactorings to simplify some method
signatures and prefer `for _ in _` over `loop { }` (at least when it
comes semi-naturally).
Improve performance of spsc_queue and stream.
This PR makes two main changes:
1. It switches the `spsc_queue` node caching strategy from keeping a shared
counter of the number of nodes in the cache to keeping a consumer only counter
of the number of node eligible to be cached.
2. It separates the consumer and producers fields of `spsc_queue` and `stream` into
a producer cache line and consumer cache line.
Overall, it speeds up `mpsc` in `spsc` mode by 2-10x.
Variance is higher than I'd like (that 2-10x speedup is on one benchmark), I believe this is due to the drop check in `send` (`fn stream::Queue::send:107`). I think this check can be combined with the sleep detection code into a version which only uses 1 shared variable, and only one atomic access per `send`, but I haven't looked through the select implementation enough to be sure.
The code currently assumes a cache line size of 64 bytes. I added a CacheAligned newtype in `mpsc` which I expect to reuse for `shared`. It doesn't really belong there, it would probably be best put in `core::sync::atomic`, but putting it in `core` would involve making it public, which I thought would require an RFC.
Benchmark runner is [here](3eca46279c/shootout), benchmarks [here](3eca46279c/queue_bench/src/lib.rs (L170-L293)).
Fixes#44512.
Refactor fmt::Display and fmt::Debug impls in ppaux
Also fixes#44887.
There was a problem that unnamed late-bound regions are *always* named `'r` while they are displayed using `std::fmt::Display`.
---
```rust
fn main() {
f(|_: (), _: ()| {});
}
fn f<F>(_: F) where F: Fn(&(), for<'r> fn(&'r ())) {}
```
Before (incorrectly shadows lifetime, `for<'r>` omitted for the second argument):
```
error[E0631]: type mismatch in closure arguments
--> test.rs:2:5
|
2 | f(|_: (), _: ()| {});
| ^ ----------------- found signature of `fn((), ()) -> _`
| |
| expected signature of `for<'r> fn(&'r (), fn(&'r ())) -> _`
|
= note: required by `f`
```
After:
```
error[E0631]: type mismatch in closure arguments
--> test.rs:2:5
|
2 | f(|_: (), _: ()| {});
| ^ ----------------- found signature of `fn((), ()) -> _`
| |
| expected signature of `for<'s> fn(&'s (), for<'r> fn(&'r ())) -> _`
|
= note: required by `f`
```
r? @nikomatsakis
ci: Fix installing the Android SDK
Apparently the https urls are broken due to some certificate validation
whatnots, and so far the least intrusive solution I've found is to just disable
that.
Apparently the https urls are broken due to some certificate validation
whatnots, and so far the least intrusive solution I've found is to just disable
that.
Fix path to x.py in bootstrap/configure.py script
We may see a help message in the end of the output of the ./configure script:
```
$ ./configure
configure: processing command line
configure:
configure: build.configure-args := []
configure:
configure: writing `config.toml` in current directory
configure:
configure: run `python ./src/bootstrap/x.py --help`
configure:
```
but the `x.py` script is actually in the rust root directory and
executing of such help string will give us error:
```
$ python ./src/bootstrap/x.py --help
python: can't open file './src/bootstrap/x.py': [Errno 2] No such file
or directory
```
This patch fixes path to the x.py script in the output of the ./configure
Update let-expressions.rs with DepNode labels
As a part of #44924, the PR has tests verified for the following dependency nodes for **let-expressions**
```
- MirValidated
- MirOptimized
- TypeCheckTables
- TypeOfItem
- GenericsOfItem
- PredicatesOfItem
- FnSignature
```
As we are more concerned with the function body, the following fingerprints do not change over compilation sessions.
```- TypeOfItem
- GenericsOfItem
- PredicatesOfItem
- FnSignature
```
r? @nikomatsakis
cc @michaelwoerister
P.S. Will add more tests as and when possible :)
Implement display_hint in gdb pretty printers
A few pretty-printers were returning a quoted string from their
to_string method. It's preferable in gdb to return a lazy string and to
let gdb handle the display by having a "display_hint" method that
returns "string" -- it lets gdb settings (like "set print ...") work, it
handles corrupted strings a bit better, and it passes the information
along to IDEs.
We may see a help message in the end of the output of the ./configure script:
$ ./configure
configure: processing command line
configure:
configure: build.configure-args := []
configure:
configure: writing `config.toml` in current directory
configure:
configure: run `python ./src/bootstrap/x.py --help`
configure:
but the x.py script is actually in the rust root directory and
executing of such help string will give us error:
$ python ./src/bootstrap/x.py --help
python: can't open file './src/bootstrap/x.py': [Errno 2] No such file
or directory
This patch fixes path to the x.py script in the output of the ./configure
incr.comp.: Move macro-export test case to src/test/incremental.
`compile-fail/incr_comp_with_macro_export.rs` was trying to role its own incremental compilation setup. This started to cause problems. There's no reason to not just make this a regular `src/test/incremental` test.
Fixes#45062.
Fix data-layout field in x86_64-unknown-linux-gnu.json test file
The current data-layout causes the following error:
> rustc: /checkout/src/llvm/lib/CodeGen/MachineFunction.cpp:151: void llvm::MachineFunction::init(): Assertion `Target.isCompatibleDataLayout(getDataLayout()) && "Can't create a MachineFunction using a Module with a " "Target-incompatible DataLayout attached\n"' failed.
The new value was generated according to [this comment by @japaric](https://github.com/rust-lang/rust/issues/31367#issuecomment-213595571).
Update comments referring to old check_method_self_type
I was browsing the code base, trying to figure out how #44874 could be implemented, and noticed some comments that were out of date and a bit misleading (`check_method_self_type` has since been renamed to `check_method_receiver`). Thought it would be an easy first contribution to Rust!
Ensure std::mem::Discriminant is Send + Sync
`PhantomData<*const T>` has the implication of Send / Syncness following
the *const T type, but the discriminant should always be Send and Sync.
Use `PhantomData<fn() -> T>` which has the same variance in T, but is Send + Sync
