Ignore NLL boring locals in polonius diagnostics
Another easy one ``@jackh726`` (the diff is inflated by blessed test expectations don't worry :)
NLLs don't compute liveness for boring locals, and therefore cannot find them in causes explaining borrows. In polonius, we don't have this liveness optimization (we may be able to do something partially similar in the future, e.g. for function parameters and the like), so we do encounter these in diagnostics even though we don't want to. This PR:
- restructures the polonius context into per-phase data, in spirit as you requested in an earlier review
- stores the locals NLLs would consider boring into the errors/diagnostics data
- ignores these if a boring local is found when trying to explain borrows
This PR fixes around 80 cases of diagnostics differences between `-Zpolonius=next` and NLLs. I've also added explicit revisions to a few polonius tests (both for the in-tree implementation as well as the datalog implementation -- even if we'll eventually remove them). I didn't do this for all the "dead" expectations that were removed from #136112 for that same reason, it's fine. I'll soon/eventually add explicit revisions where they're needed: there's only a handful of tests left to fix.
r? ``@jackh726``
diagnostics: fix borrowck suggestions for if/while let conditionals
This code detects the case where one of the borrows is inside the let init expr while the other end is not. If that happens, we don't want to suggest adding a semicolon, because it won't work.
Fixes#133941
Make comma separated lists of anything easier to make for errors
Provide a new function `listify`, meant to be used in cases similar to `pluralize!`. When you have a slice of arbitrary elements that need to be presented to the user, `listify` allows you to turn that into a list of comma separated strings.
This reduces a lot of redundant logic that happens often in diagnostics.
Rework "long type names" printing logic
Make it so more type-system types can be printed in a shortened version (like `Predicate`s).
Centralize printing the information about the "full type name path".
Make the "long type path" for the file where long types are written part of `Diag`, so that it becomes easier to keep track of it, and ensure it will always will be printed out last in the diagnostic by making its addition to the output implicit.
Tweak the shortening of types in "expected/found" labels.
Remove dead file `note.rs`.
This code detects the case where one of the borrows is inside the
let init expr while the other end is not. If that happens, we don't
want to suggest adding a semicolon, because it won't work.
Implement MIR lowering for unsafe binders
This is the final bit of the unsafe binders puzzle. It implements MIR, CTFE, and codegen for unsafe binders, and enforces that (for now) they are `Copy`. Later on, I'll introduce a new trait that relaxes this requirement to being "is `Copy` or `ManuallyDrop<T>`" which more closely models how we treat union fields.
Namely, wrapping unsafe binders is now `Rvalue::WrapUnsafeBinder`, which acts much like an `Rvalue::Aggregate`. Unwrapping unsafe binders are implemented as a MIR projection `ProjectionElem::UnwrapUnsafeBinder`, which acts much like `ProjectionElem::Field`.
Tracking:
- https://github.com/rust-lang/rust/issues/130516
Make it so more type-system types can be printed in a shortened version (like `Predicate`s).
Centralize printing the information about the "full type name path".
Make the "long type path" for the file where long types are written part of `Diag`, so that it becomes easier to keep track of it, and ensure it will always will be printed out last in the diagnostic by making its addition to the output implicit.
Tweak the shortening of types in "expected/found" labels.
Remove dead file `note.rs`.
Provide a new function `listify`, meant to be used in cases similar to `pluralize!`. When you have a slice of arbitrary elements that need to be presented to the user, `listify` allows you to turn that into a list of comma separated strings.
This reduces a lot of redundant logic that happens often in diagnostics.
add constraint graph to polonius MIR dump
Another easy one while I work on diagnostics. This PR adds a mermaid visualization of the polonius constraint graph to the polonius MIR dump.
Adding kills is left to a future PR (until they're encoded in edges directly or I set up recording debugging info in and out of the analysis), because right now they're only computed during traversal.
[Here's](https://gistpreview.github.io/?096b0131e8258f9a3125c55c7ac369bc) how that looks.
r? `@matthewjasper` but as always feel free to reroll.
It's a function that does stuff with MIR and yet it weirdly has its own
module in `rustc_middle::util`. This commit moves it into
`rustc_middle::mir`, a more sensible home.
Simplify and consolidate the way we handle construct `OutlivesEnvironment` for lexical region resolution
This is best reviewed commit-by-commit. I tried to consolidate the API for lexical region resolution *first*, then change the API when it was finally behind a single surface.
r? lcnr or reassign
Tweak `&mut self` suggestion span
```
error[E0596]: cannot borrow `*self.s` as mutable, as it is behind a `&` reference
--> $DIR/issue-38147-1.rs:17:9
|
LL | self.s.push('x');
| ^^^^^^ `self` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: consider changing this to be a mutable reference
|
LL | fn f(&mut self) {
| +++
```
Note the suggestion to add `mut` instead of replacing the entire `&self` with `&mut self`.
Add mermaid graphs of NLL regions and SCCs to polonius MIR dump
This PR expands the polonius MIR dump again with a couple of mermaid charts ported from the graphviz version:
- the NLL region graph
- and the NLL SCCs
I still have done zero visual design on this until now, but [here's](https://gistpreview.github.io/?fbbf900fed2ad21108c7ca0353456398) how it looks (i.e. still bad) just to give an idea of the result.
r? `````@matthewjasper````` (feel free to reassign) or anyone
```
error[E0596]: cannot borrow `*self.s` as mutable, as it is behind a `&` reference
--> $DIR/issue-38147-1.rs:17:9
|
LL | self.s.push('x');
| ^^^^^^ `self` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: consider changing this to be a mutable reference
|
LL | fn f(&mut self) {
| +++
```
Note the suggestion to add `mut` instead of replacing the entire `&self` with `&mut self`.
Pass spans to `perform_locally_in_new_solver`
Nothing changes yet, but we may be able to use these spans in the future once we start dealing w the response region constraints better.
r? lcnr
Expand polonius MIR dump
This PR starts expanding the polonius MIR:
- switches to an HTML file, to show graphs in the same document as the MIR dump, share them more easily since it's a single file that can be hosted as a gist, and also to allow for interactivity in the near future.
- adds the regular NLL MIR + polonius constraints
- embeds a mermaid version of the CFG, similar to the graphviz one, but that needs a smaller js than `dot`'s emscripten js from graphvizonline
[Here's an example](https://gistpreview.github.io/?0c18f2a59b5e24ac0f96447aa34ffe00) of how it looks.
---
In future PRs: mermaid graphs of the NLL region graph, of the NLL SCCs, of the polonius localized outlives constraints, and the interactive polonius MIR dump.
r? ```@matthewjasper```
Use short ty string for move errors
```
error[E0382]: use of moved value: `x`
--> bay.rs:14:14
|
12 | fn foo(x: D) {
| - move occurs because `x` has type `(((..., ..., ..., ...), ..., ..., ...), ..., ..., ...)`, which does not implement the `Copy` trait
13 | let _a = x;
| - value moved here
14 | let _b = x; //~ ERROR use of moved value
| ^ value used here after move
|
= note: the full type name has been written to 'bay.long-type-14349227078439097973.txt'
= note: consider using `--verbose` to print the full type name to the console
help: consider cloning the value if the performance cost is acceptable
|
13 | let _a = x.clone();
| ++++++++
```
Address 4th case in #135919.
```
error[E0382]: use of moved value: `x`
--> bay.rs:14:14
|
12 | fn foo(x: D) {
| - move occurs because `x` has type `(((..., ..., ..., ...), ..., ..., ...), ..., ..., ...)`, which does not implement the `Copy` trait
13 | let _a = x;
| - value moved here
14 | let _b = x; //~ ERROR use of moved value
| ^ value used here after move
|
= note: the full type name has been written to 'bay.long-type-14349227078439097973.txt'
= note: consider using `--verbose` to print the full type name to the console
help: consider cloning the value if the performance cost is acceptable
|
13 | let _a = x.clone();
| ++++++++
```
Rollup of 7 pull requests
Successful merges:
- #133700 (const-eval: detect more pointers as definitely not-null)
- #135290 (Encode constraints that hold at all points as logical edges in location-sensitive polonius)
- #135478 (Run clippy for rustc_codegen_gcc on CI)
- #135583 (Move `std::pipe::*` into `std::io`)
- #135612 (Include x scripts in tarballs)
- #135624 (ci: mirror buildkit image to ghcr)
- #135661 (Stabilize `float_next_up_down`)
r? `@ghost`
`@rustbot` modify labels: rollup
Instead of materializing `Locations::All` constraints as physical edges
at all the points in the CFG, we record them as logical edges and only
materialize them during traversal as successors for a given node.
This fixes the slowness/hang in the `saturating-float-casts.rs` test.
