- Add back various diagnostic methods on `Session`.
It seems unfortunate to duplicate these in so many places, but in the
meantime, making the API inconsistent between `Session` and `Diagnostic`
also seems unfortunate.
- Add back TyCtxtAt methods
These will hopefully be used in the near future.
- Add back `with_const`, it would need to be added soon after anyway.
- Add back `split()` and `get_mut()`, they're useful.
Found with https://github.com/est31/warnalyzer.
Dubious changes:
- Is anyone else using rustc_apfloat? I feel weird completely deleting
x87 support.
- Maybe some of the dead code in rustc_data_structures, in case someone
wants to use it in the future?
- Don't change rustc_serialize
I plan to scrap most of the json module in the near future (see
https://github.com/rust-lang/compiler-team/issues/418) and fixing the
tests needed more work than I expected.
TODO: check if any of the comments on the deleted code should be kept.
Add function core::iter::zip
This makes it a little easier to `zip` iterators:
```rust
for (x, y) in zip(xs, ys) {}
// vs.
for (x, y) in xs.into_iter().zip(ys) {}
```
You can `zip(&mut xs, &ys)` for the conventional `iter_mut()` and
`iter()`, respectively. This can also support arbitrary nesting, where
it's easier to see the item layout than with arbitrary `zip` chains:
```rust
for ((x, y), z) in zip(zip(xs, ys), zs) {}
for (x, (y, z)) in zip(xs, zip(ys, zs)) {}
// vs.
for ((x, y), z) in xs.into_iter().zip(ys).zip(xz) {}
for (x, (y, z)) in xs.into_iter().zip((ys.into_iter().zip(xz)) {}
```
It may also format more nicely, especially when the first iterator is a
longer chain of methods -- for example:
```rust
iter::zip(
trait_ref.substs.types().skip(1),
impl_trait_ref.substs.types().skip(1),
)
// vs.
trait_ref
.substs
.types()
.skip(1)
.zip(impl_trait_ref.substs.types().skip(1))
```
This replaces the tuple-pair `IntoIterator` in #78204.
There is prior art for the utility of this in [`itertools::zip`].
[`itertools::zip`]: https://docs.rs/itertools/0.10.0/itertools/fn.zip.html
make unaligned_references future-incompat lint warn-by-default
and also remove the safe_packed_borrows lint that it replaces.
`std::ptr::addr_of!` has hit beta now and will hit stable in a month, so I propose we start fixing https://github.com/rust-lang/rust/issues/27060 for real: creating a reference to a field of a packed struct needs to eventually become a hard error; this PR makes it a warn-by-default future-incompat lint. (The lint already existed, this just raises its default level.) At the same time I removed the corresponding code from unsafety checking; really there's no reason an `unsafe` block should make any difference here.
For references to packed fields outside `unsafe` blocks, this means `unaligned_refereces` replaces the previous `safe_packed_borrows` warning with a link to https://github.com/rust-lang/rust/issues/82523 (and no more talk about unsafe blocks making any difference). So behavior barely changes, the warning is just worded differently. For references to packed fields inside `unsafe` blocks, this PR shows a new future-incompat warning.
Closes https://github.com/rust-lang/rust/issues/46043 because that lint no longer exists.
combine: stop eagerly evaluating consts
`super_relate_consts` eagerly evaluates constants which doesn't seem too great.
I now also finally understand why all of the unused substs test passed. The reason being
that we just evaluated the constants in `super_relate_consts` 😆
While this change isn't strictly necessary as evaluating consts here doesn't hurt, it still feels a lot cleaner to do it this way
r? `@oli-obk` `@nikomatsakis`
Allow for reading raw bytes from rustc_serialize::Decoder without unsafe code
The current `read_raw_bytes` method requires using `MaybeUninit` and `unsafe`. I don't think this is necessary. Let's see if a safe interface has any performance drawbacks.
This is a followup to #83273 and will make it easier to rebase #82183.
r? `@cjgillot`
Refactor rustc_resolve::late::lifetimes to resolve per-item
There are some changes to tests that I'd like some feedback on; so this is still WIP.
The reason behind this change will (hopefully) allow us to (as part of #76814) be able to essentially use the lifetime resolve code to resolve *all* late bound vars (including those of super traits). Currently, it only resolves those that are *syntactically* in scope. In #76814, I'm essentially finding that I would essentially have to redo the passing of bound vars through scopes (i.e. when instantiating a poly trait ref), and that's what this code does anyways. However, to be able to do this (ask super traits what bound vars are in scope), we have to be able to resolve items separately.
The first commit is actually partially orthogonal. Essentially removing one use of late bound debruijn indices.
Not exactly sure who would be best to review here.
Let r? `@nikomatsakis`
GenericParam does not need to be a HIR owner.
The special case is not required.
Universal impl traits design to regular generic parameters, and their content is owned by the enclosing item.
Existential (and opaque) impl traits generate their own enclosing item, and are collected through it.
coverage bug fixes and optimization support
Adjusted LLVM codegen for code compiled with `-Zinstrument-coverage` to
address multiple, somewhat related issues.
Fixed a significant flaw in prior coverage solution: Every counter
generated a new counter variable, but there should have only been one
counter variable per function. This appears to have bloated .profraw
files significantly. (For a small program, it increased the size by
about 40%. I have not tested large programs, but there is anecdotal
evidence that profraw files were way too large. This is a good fix,
regardless, but hopefully it also addresses related issues.
Fixes: #82144
Invalid LLVM coverage data produced when compiled with -C opt-level=1
Existing tests now work up to at least `opt-level=3`. This required a
detailed analysis of the LLVM IR, comparisons with Clang C++ LLVM IR
when compiled with coverage, and a lot of trial and error with codegen
adjustments.
The biggest hurdle was figuring out how to continue to support coverage
results for unused functions and generics. Rust's coverage results have
three advantages over Clang's coverage results:
1. Rust's coverage map does not include any overlapping code regions,
making coverage counting unambiguous.
2. Rust generates coverage results (showing zero counts) for all unused
functions, including generics. (Clang does not generate coverage for
uninstantiated template functions.)
3. Rust's unused functions produce minimal stubbed functions in LLVM IR,
sufficient for including in the coverage results; while Clang must
generate the complete LLVM IR for each unused function, even though
it will never be called.
This PR removes the previous hack of attempting to inject coverage into
some other existing function instance, and generates dedicated instances
for each unused function. This change, and a few other adjustments
(similar to what is required for `-C link-dead-code`, but with lower
impact), makes it possible to support LLVM optimizations.
Fixes: #79651
Coverage report: "Unexecuted instantiation:..." for a generic function
from multiple crates
Fixed by removing the aforementioned hack. Some "Unexecuted
instantiation" notices are unavoidable, as explained in the
`used_crate.rs` test, but `-Zinstrument-coverage` has new options to
back off support for either unused generics, or all unused functions,
which avoids the notice, at the cost of less coverage of unused
functions.
Fixes: #82875
Invalid LLVM coverage data produced with crate brotli_decompressor
Fixed by disabling the LLVM function attribute that forces inlining, if
`-Z instrument-coverage` is enabled. This attribute is applied to
Rust functions with `#[inline(always)], and in some cases, the forced
inlining breaks coverage instrumentation and reports.
FYI: `@wesleywiser`
r? `@tmandry`
This currently creates a field which is always false on GenericParamDefKind for future use when
consts are permitted to have defaults
Update const_generics:default locations
Previously just ignored them, now actually do something about them.
Fix using type check instead of value
Add parsing
This adds all the necessary changes to lower const-generics defaults from parsing.
Change P<Expr> to AnonConst
This matches the arguments passed to instantiations of const generics, and makes it specific to
just anonymous constants.
Attempt to fix lowering bugs
This saves us both the Freeze/Unpin queries, and avoids placing
noalias attributes, which have a compile-time impact on LLVM
even in optnone builds (due to always_inline functions).
Such structures may contain self-references, in which case the
same location may be accessible through a pointer that is not
based-on the noalias pointer.
This is still grey area as far as language semantics are concerned,
but checking for !Unpin as an indicator for self-referential
sturctures seems like a good approach for the meantime.
The frontend shouldn't be deciding whether or not to use mutable
noalias attributes, as this is a pure LLVM concern. Only provide
the necessary information and do the actual decision in
codegen_llvm.
const_evaluatable_checked: Stop eagerly erroring in `is_const_evaluatable`
Fixes#82279
We don't want to be emitting errors inside of is_const_evaluatable because we may call this during selection where it should be able to fail silently
There were two errors being emitted in `is_const_evaluatable`. The one causing the compile error in #82279 was inside the match arm for `FailureKind::MentionsParam` but I moved the other error being emitted too since it made things cleaner imo
The `NotConstEvaluatable` enum \*should\* have a fourth variant for when we fail to evaluate a concrete const, e.g. `0 - 1` but that cant happen until #81339
cc `@oli-obk` `@lcnr`
r? `@nikomatsakis`
Adjusted LLVM codegen for code compiled with `-Zinstrument-coverage` to
address multiple, somewhat related issues.
Fixed a significant flaw in prior coverage solution: Every counter
generated a new counter variable, but there should have only been one
counter variable per function. This appears to have bloated .profraw
files significantly. (For a small program, it increased the size by
about 40%. I have not tested large programs, but there is anecdotal
evidence that profraw files were way too large. This is a good fix,
regardless, but hopefully it also addresses related issues.
Fixes: #82144
Invalid LLVM coverage data produced when compiled with -C opt-level=1
Existing tests now work up to at least `opt-level=3`. This required a
detailed analysis of the LLVM IR, comparisons with Clang C++ LLVM IR
when compiled with coverage, and a lot of trial and error with codegen
adjustments.
The biggest hurdle was figuring out how to continue to support coverage
results for unused functions and generics. Rust's coverage results have
three advantages over Clang's coverage results:
1. Rust's coverage map does not include any overlapping code regions,
making coverage counting unambiguous.
2. Rust generates coverage results (showing zero counts) for all unused
functions, including generics. (Clang does not generate coverage for
uninstantiated template functions.)
3. Rust's unused functions produce minimal stubbed functions in LLVM IR,
sufficient for including in the coverage results; while Clang must
generate the complete LLVM IR for each unused function, even though
it will never be called.
This PR removes the previous hack of attempting to inject coverage into
some other existing function instance, and generates dedicated instances
for each unused function. This change, and a few other adjustments
(similar to what is required for `-C link-dead-code`, but with lower
impact), makes it possible to support LLVM optimizations.
Fixes: #79651
Coverage report: "Unexecuted instantiation:..." for a generic function
from multiple crates
Fixed by removing the aforementioned hack. Some "Unexecuted
instantiation" notices are unavoidable, as explained in the
`used_crate.rs` test, but `-Zinstrument-coverage` has new options to
back off support for either unused generics, or all unused functions,
which avoids the notice, at the cost of less coverage of unused
functions.
Fixes: #82875
Invalid LLVM coverage data produced with crate brotli_decompressor
Fixed by disabling the LLVM function attribute that forces inlining, if
`-Z instrument-coverage` is enabled. This attribute is applied to
Rust functions with `#[inline(always)], and in some cases, the forced
inlining breaks coverage instrumentation and reports.
Replace closures_captures and upvar_capture with closure_min_captures
Removed all uses of closures_captures and upvar_capture and refactored code to work with closure_min_captures. This also involved removing functions that were no longer needed like the bridge.
Closes https://github.com/rust-lang/project-rfc-2229/issues/18
r? `@nikomatsakis`
make changes to liveness to use closure_min_captures
use different span
borrow check uses new structures
rename to CapturedPlace
stop using upvar_capture in regionck
remove the bridge
cleanup from rebase + remove the upvar_capture reference from mutability_errors.rs
remove line from livenes test
make our unused var checking more consistent
update tests
adding more warnings to the tests
move is_ancestor_or_same_capture to rustc_middle/ty
update names to reflect the closures
add FIXME
check that all captures are immutable borrows before returning
add surrounding if statement like the original
move var out of the loop and rename
Co-authored-by: Logan Mosier <logmosier@gmail.com>
Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
Make source-based code coverage compatible with MIR inlining
When codegenning code coverage use the instance that coverage data was
originally generated for, to ensure basic level of compatibility with
MIR inlining.
Fixes#83061
ast/hir: Rename field-related structures
I always forget what `ast::Field` and `ast::StructField` mean despite working with AST for long time, so this PR changes the naming to less confusing and more consistent.
- `StructField` -> `FieldDef` ("field definition")
- `Field` -> `ExprField` ("expression field", not "field expression")
- `FieldPat` -> `PatField` ("pattern field", not "field pattern")
Various visiting and other methods working with the fields are renamed correspondingly too.
The second commit reduces the size of `ExprKind` by boxing fields of `ExprKind::Struct` in preparation for https://github.com/rust-lang/rust/pull/80080.
Do not insert impl_trait_in_bindings opaque definitions twice.
The reference to the item already appears inside the `OpaqueDef`. It does not need to be repeated as a statement.
Implement (but don't use) valtree and refactor in preparation of use
This PR does not cause any functional change. It refactors various things that are needed to make valtrees possible. This refactoring got big enough that I decided I'd want it reviewed as a PR instead of trying to make one huge PR with all the changes.
cc `@rust-lang/wg-const-eval` on the following commits:
* 2027184 implement valtree
* eeecea9 fallible Scalar -> ScalarInt
* 042f663 ScalarInt convenience methods
cc `@eddyb` on ef04a6d
cc `@rust-lang/wg-mir-opt` for cf1700c (`mir::Constant` can now represent either a `ConstValue` or a `ty::Const`, and it is totally possible to have two different representations for the same value)
2229: Handle patterns within closures correctly when `capture_disjoint_fields` is enabled
This PR fixes several issues related to handling patterns within closures when `capture_disjoint_fields` is enabled.
1. Matching is always considered a use of the place, even with `_` patterns
2. Compiler ICE when capturing fields in closures through `let` assignments
To do so, we
- Introduced new Fake Reads
- Delayed use of `Place` in favor of `PlaceBuilder`
- Ensured that `PlaceBuilder` can be resolved before attempting to extract `Place` in any of the pattern matching code
Closes rust-lang/project-rfc-2229/issues/27
Closes rust-lang/project-rfc-2229/issues/24
r? `@nikomatsakis`
StructField -> FieldDef ("field definition")
Field -> ExprField ("expression field", not "field expression")
FieldPat -> PatField ("pattern field", not "field pattern")
Also rename visiting and other methods working on them.
83054 introduced validation of scalar range attributes, but panicking
code that uses the attribute remained reachable. Use `delay_span_bug`
instead to avoid the ICE.
Consider functions to be reachable for code coverage purposes, either
when they reach the code generation directly, or indirectly as inlined
part of another function.
Don't encode file information for span with a dummy location
Fixes#83112
The location information for a dummy span isn't real, so don't encode
it. This brings the incr comp cache code into line with the Span
`StableHash` impl, which doesn't hash the location information for dummy
spans.
Previously, we would attempt to load the 'original' file from a dummy
span - if the file id changed (e.g. due to being moved on disk), we would get an
ICE, since the Span was still valid due to its hash being unchanged.
Remove unused `opt_local_def_id_to_hir_id` function
Found while investigating #82933 - all LocalDefIds are expected to have
HirIds, there's no point in pretending otherwise.
Update to rustc-rayon 0.3.1
This pulls in rust-lang/rustc-rayon#8 to fix#81425. (h/t `@ammaraskar)`
That revealed weak constraints on `rustc_arena::DropArena`, because its
`DropType` was holding type-erased raw pointers to generic `T`. We can
implement `Send` for `DropType` (under `cfg(parallel_compiler)`) by
requiring all `T: Send` before they're type-erased.
Fixes#83112
The location information for a dummy span isn't real, so don't encode
it. This brings the incr comp cache code into line with the Span
`StableHash` impl, which doesn't hash the location information for dummy
spans.
Previously, we would attempt to load the 'original' file from a dummy
span - if the file id changed (e.g. due to being moved on disk), we would get an
ICE, since the Span was still valid due to its hash being unchanged.
Value trees won't have scalar ptr at all, so we need a scalar int printing method anyway. This way we'll be able to share that method between all const representations.
valtree is a version of constants that is inherently safe to be used within types.
This is in contrast to ty::Const which can have different representations of the same value. These representation differences can show up in hashing or equality comparisons, breaking type equality of otherwise equal types.
valtrees do not have this problem.
Shorten `rustc_middle::ty::mod`
Related to #60302.
This PR moves all `Adt*`, `Assoc*`, `Generic*`, and `UpVar*` types to separate files.
This, alongside some `use` reordering, puts `mod.rs` at ~2,200 lines, thus removing the `// ignore-tidy-filelength`.
The particular groups were chosen as they had 4 or more "substantive" members.
This pulls in rust-lang/rustc-rayon#8 to fix#81425. (h/t @ammaraskar)
That revealed weak constraints on `rustc_arena::DropArena`, because its
`DropType` was holding type-erased raw pointers to generic `T`. We can
implement `Send` for `DropType` (under `cfg(parallel_compiler)`) by
requiring all `T: Send` before they're type-erased.
