This handles using deref patterns to choose the correct match arm. This
does not handle bindings or guards.
Co-authored-by: Deadbeef <ent3rm4n@gmail.com>
PatRangeBoundary::compare_with: als add a fast-path for signed integers
Not sure if we have a benchmark that hits this... but it seems odd to only do this for unsigned integers.
Match hyphen in multi-revision comment matchers
Currently, the matcher `//[rev-foo,rev-bar]~` does not get selected by the regex. Change the matcher to include `-`.
Fix capturing duplicated lifetimes via parent in `precise_captures` (`impl use<'...>`)
For technical reasons related to the way that `Self` and `T::Assoc` are lowered from HIR -> `rustc_middle::ty`, an opaque may mention in its bounds both the original early-bound lifetime from the parent `impl`/`fn`, *and* the *duplicated* early-bound lifetime on the opaque.
This is fine -- and has been fine since `@cjgillot` rewrote the way we handled opaque lifetime captures, and we went further to allow this behavior explicitly in https://github.com/rust-lang/rust/pull/115659. It's worthwhile to read this PR's technical section to recall how this duplication works and when it acts surprisingly.
The problem here is that the check that make sure that `impl use<'a, 'b>` lists all of the opaque's captured lifetimes wasn't smart enough to consider both these captured lifetimes and the original lifetimes they're duplicated from to be equal. This PR fixes that.
r? oli-obk
Implement Modified Condition/Decision Coverage
This is an implementation based on llvm backend support (>= 18) by `@evodius96` and branch coverage support by `@Zalathar.`
### Major changes:
* Add -Zcoverage-options=mcdc as switch. Now coverage options accept either `no-branch`, `branch`, or `mcdc`. `mcdc` also enables `branch` because it is essential to work.
* Add coverage mapping for MCDCBranch and MCDCDecision. Note that MCDCParameter evolves from llvm 18 to llvm 19. The mapping in rust side mainly references to 19 and is casted to 18 types in llvm wrapper.
* Add wrapper for mcdc instrinc functions from llvm. And inject associated statements to mir.
* Add BcbMappingKind::Decision, I'm not sure is it proper but can't find a better way temporarily.
* Let coverage-dump support parsing MCDCBranch and MCDCDecision from llvm ir.
* Add simple tests to check whether mcdc works.
* Same as clang, currently rustc does not generate instrument for decision with more than 6 condtions or only 1 condition due to considerations of resource.
### Implementation Details
1. To get information about conditions and decisions, `MCDCState` in `BranchInfoBuilder` is used during hir lowering to mir. For expressions with logical op we call `Builder::visit_coverage_branch_operation` to record its sub conditions, generate condition ids for them and save their spans (to construct the span of whole decision). This process mainly references to the implementation in clang and is described in comments over `MCDCState::record_conditions`. Also true marks and false marks introduced by branch coverage are used to detect where the decision evaluation ends: the next id of the condition == 0.
2. Once the `MCDCState::decision_stack` popped all recorded conditions, we can ensure that the decision is checked over and push it into `decision_spans`. We do not manually insert decision span to avoid complexity from then_else_break in nested if scopes.
3. When constructing CoverageSpans, add condition info to BcbMappingKind::Branch and decision info to BcbMappingKind::Decision. If the branch mapping has non-zero condition id it will be transformed to MCDCBranch mapping and insert `CondBitmapUpdate` statements to its evaluated blocks. While decision bcb mapping will insert `TestVectorBitmapUpdate` in all its end blocks.
### Usage
```bash
echo "[build]\nprofiler=true" >> config.toml
./x build --stage 1
./x test tests/coverage/mcdc_if.rs
```
to build the compiler and run tests.
```shell
export PATH=path/to/llvm-build:$PATH
rustup toolchain link mcdc build/host/stage1
cargo +mcdc rustc --bin foo -- -Cinstrument-coverage -Zcoverage-options=mcdc
cd target/debug
LLVM_PROFILE_FILE="foo.profraw" ./foo
llvm-profdata merge -sparse foo.profraw -o foo.profdata
llvm-cov show ./foo -instr-profile=foo.profdata --show-mcdc
```
to check "foo" code.
### Problems to solve
For now decision mapping will insert statements to its all end blocks, which may be optimized by inserting a final block of the decision. To do this we must also trace the evaluated value at each end of the decision and join them separately.
This implementation is not heavily tested so there should be some unrevealed issues. We are going to check our rust products in the next. Please let me know if you had any suggestions or comments.
Disable SimplifyToExp in MatchBranchSimplification
Due to the miscompilation mentioned in #124150, We need to disable MatchBranchSimplification temporarily.
To fully resolve this issue, my plan is:
1. Disable SimplifyToExp in MatchBranchSimplification (this PR).
2. Remove all potentially unclear transforms in #124122.
3. Gradually add back the removed transforms (possibly multiple PRs).
r? `@Nilstrieb` or `@oli-obk`
This adds a dedicated check for the lower bound
(if it is outside of ASCII range) to the output of the `unicode-table-generator` tool.
This generalized the ASCII-only fast-path, but only for the `Grapheme_Extend` property for now,
as that is the only one with a lower bound outside of ASCII.
Make `checked` ops emit *unchecked* LLVM operations where feasible
For things with easily pre-checked overflow conditions -- shifts and unsigned subtraction -- write the checked methods in such a way that we stop emitting wrapping versions of them.
For example, today <https://rust.godbolt.org/z/qM9YK8Txb> neither
```rust
a.checked_sub(b).unwrap()
```
nor
```rust
a.checked_sub(b).unwrap_unchecked()
```
actually optimizes to `sub nuw`. After this PR they do.
cc #103299
Update cargo
8 commits in 6f06fe908a5ee0f415c187f868ea627e82efe07d..80d5b607dde6ef97dfff4e23923822c01d2bb036
2024-04-16 18:47:44 +0000 to 2024-04-19 18:39:22 +0000
- fix 13773 - 'cargo build' fails when list_files() with gix is triggered (rust-lang/cargo#13777)
- fix(toml): Don't crash on parse errors that point to multi-byte character (rust-lang/cargo#13780)
- fix(toml)!: Disallow source-less dependencies (rust-lang/cargo#13775)
- fix(msrv): Put MSRV-aware resolver behind a config (rust-lang/cargo#13769)
- fix(msrv): Error, rather than panic, on rust-version 'x' (rust-lang/cargo#13771)
- fix(credential): trim newlines in tokens from stdin (rust-lang/cargo#13770)
- test(msrv): Re-organize MSRV tests (rust-lang/cargo#13767)
- feat(install): Including Locking message (rust-lang/cargo#13764)
r? ghost
Address reuse improvements and fixes
- when an address gets reused, establish a happens-before link in the data race model
- do not reuse stack addresses, and make the reuse rate configurable
Fixes https://github.com/rust-lang/miri/issues/3450
Rollup of 5 pull requests
Successful merges:
- #123571 (Correctly change type when adding adjustments on top of `NeverToAny`)
- #123729 (run-make: refactor out command wrappers for `clang` and `llvm-readobj`)
- #124106 (Don't repeatedly duplicate TAIT lifetimes for each subsequently nested TAIT)
- #124149 (rustdoc-search: fix description on aliases in results)
- #124155 (bootstrap: don't use rayon for sysinfo)
r? `@ghost`
`@rustbot` modify labels: rollup
