Explanation: Unowned result conventions do not work well with OSSA. Retain the
result right after the call when we come out of OSSA so we can treat the
returned value as if it was owned when we do optimizations.
This fix a miscompilation due to the DestroyAddrHoisting pass hoisting destroys
above copies with unowned sources. When the destroyed object was the last
reference to the pointed memory the copy is happening too late resulting in
a use after free.
Issues: rdar://160462854
Original PRs: #84612
Risk: We change where retaining of the unowned return values
happen in the optimization pipeline. It is hard to anticipate all the
possible effects but it should make the optimizer more correct.
Testing: Added a compiler test.
Reviewers: @eeckstein, @atrick
When calling a C++ function that takes a reference to a pointer to a foreign reference type, Swift would previously pass a pointer to the foreign reference type as an argument (instead of a reference to a pointer), which resulted in invalid memory accesses.
This was observed when using `std::vector<ImmortalRef*>::push_back`.
rdar://150791778
(cherry picked from commit 0a766e59ce)
`end_borrow` instructions may end the scopes introduced by `load_borrow`
or `store_borrow` instructions, or those introduced by `begin_borrow`
whose operand's guaranteed root includes a `load_borrow`.
Previously, such scope ending instructions which end the scope
associated with a borrowing load or store were not regarded as accessing
the loaded-from or stored-to address. One consequence of this is that
they were not regarded as accessing pointers and thus not as deinit
barriers; that in turn resulted in `destroy_addr`s being hoisted into
such borrow scopes.
Here this is fixed by regarding such `end_borrow`s to access the
loaded-from or stored-to address of the scope-introducing `load_borrow`
or `store_borrow` respectively.
rdar://157772187
Specifically, we write a string out like:
sil [isolation "$REPRESENTATION OF ISOLATION"] @function : $@convention(thin) ...
The idea is that by using a string, we avoid parsing issues of the isolation and
have flexibility. I left in the way we put isolation into the comment above
functions so I did not break any tests that rely on it. I also made it so that
we only accept this with sil tests that pass in the flag
"sil-print-function-isolation-info". I am going to for the next release put in a
full real implementation of this that allows for actor isolation to become a
true first class citizen in SIL. But for now this at least lets us write tests
in the short term.
Since this is temporary and behind a flag, I did not add support for
serialization since this is just for writing textual SIL tests.
(cherry picked from commit ee3027c2ca)
Conflicts:
lib/SIL/Parser/ParseSIL.cpp
C code is highly likely to want to use pointers as references between dependent
structs, and we would like to be able to readily map these to lifetime-dependent
Swift values. Making C types addressable-for-dependencies ensures that any function
producing a dependency on such a value receives a stable in-memory address for that
value, allowing borrows and inout accesses to always be representable as pointers.
rdar://153648393
OSSA lifetime canonicalization can take a very long time in certain
cases in which there are large basic blocks. to mitigate this, add logic
to skip walking the liveness boundary for extending liveness to dead
ends when there aren't any dead ends in the function.
Updates `DeadEndBlocks` with a new `isEmpty` method and cache to
determine if there are any dead-end blocks in a given function.
(cherry picked from commit 1f3f830fc7)
Every `LowerType::visit*` function eventually calls through to a
`LowerType::handle*` function. After
https://github.com/swiftlang/swift/pull/81581, every
`LowerType::handle*` needs to set the `hasPack` flag based on the
passed-in type by calling `mergeHasPack`. Add the missing call in the
`handleAggregateByProperties` function.
rdar://152580661
Initially this declaration is going to be used to determine
per-file default actor isolation i.e. `using @MainActor` and
`using nonisolated` but it could be extended to support other
file-global settings in the future.
(cherry picked from commit aabfebec03)
When hoisting destroys of aggregates, an attempt is made to fold the
destroys of individual fields into the foregoing instructions. If the
aggregate is noncopyable, this transformation is illegal.
When hoisting destroys of aggregates, an attempt is made to fold the
destroys of individual fields into the foregoing instructions. If the
aggregate is nonescapable, this transformation is illegal.
rdar://152195094
Key paths can't reference non-escapable or non-copyable storage declarations,
so we don't need to refer to them resiliently, and can elide their property
descriptors.
However, declarations may still be conditionally Copyable and Escapable, and
if so, then they still need a property descriptor for resilient key path
references. When a property or subscript can be used in a context where it
is fully Copyable and Escapable, emit the property descriptor in a generic
environment constrained by the necessary conditional constraints.
Fixes rdar://151628396.
This prevents simplification and SILCombine passes to remove (alive) `mark_dependence_addr`.
The instruction is conceptually equivalent to
```
%v = load %addr
%d = mark_dependence %v on %base
store %d to %addr
```
Therefore the address operand has to be defined as writing to the address.
- Extend `@_inheritActorContext` attribute to support optional `always` modifier.
The new modifier will make closure context isolated even if the parameter is not
captured by the closure.
- Implementation `@_inheritActorContext` attribute validation - it could only be
used on parameter that have `@Sendable` or `sending` and `@isolated(any)` or
`async` function type (downgraded to a warning until future major Swift mode
to avoid source compatibility issues).
- Add a new language feature that guards use of `@_inheritActorContext(always)` in swift interface files
- Update `getLoweredLocalCaptures` to add an entry for isolation parameter implicitly captured by `@_inheritActorContext(always)`
- Update serialization code to store `always` modifier
(cherry picked from commit 04d46760bb)
(cherry picked from commit c050e8f75a)
(cherry picked from commit c0aca5384b)
(cherry picked from commit a4f6d710cf)
(cherry picked from commit 6c911f5d42)
(cherry picked from commit 17b8f7ef12)
Not used (yet), but needed to implement SIMD.replacing(with:where:)
idiomatically, and probably useful otherwise.
**Explanation:** Makes select available in Swift's builtin module, which
allows implementing concrete SIMD operations more efficiently.
**Risk:** Low. New builtin protected by a feature flag, currently
unused.
**Testing:** New tests added.
**Reviewers:** @eeckstein, @Azoy
**Main branch PR:** https://github.com/swiftlang/swift/pull/81598
Immortal C++ foreign reference types get TrivialTypeLowering instead of ReferenceTypeLowering, since they do not have retain/release lifetime operations. This was tripping up an assertion in SILVerifier.
rdar://147251759 / resolves https://github.com/swiftlang/swift/issues/80065
(cherry picked from commit 2e3df1c0f3)
To determine whether an instruction may require pack metadata, the types
of its operands are examined.
Previously, the top level type was checked for having a pack in its
signature, and the whole type was checked for having a type anywhere in
its layout (via TypeLowering). This didn't account for the case where
the metadata was required for a resilient type which uses a pack in its
signature.
Here, during type lowering, a type having a pack in its signature is
counted towards the type having a pack.
Fixes a compiler crash.
rdar://147207926
We were using the isolation from the witness not from the requirement which we
are supposed to do. The witness thunk thunks the isolation from the requirement
to the witness so from an ABI perspective it should have the interface implied
by the requirement's isolation since that is what callers of the witness method
will expect.
rdar://151394209
(cherry picked from commit 39a013f807)
This will cause tests today to crash since even though we are placing the
isolation now, to make it easier to read, I left in the old isolation selecting
code. This code uses the witness's isolation instead of the requirement's
isolation which is incorrect since the protocol witness thunk needs to look the
requirement from an ABI perspective since the two must be substitutable. The
crash comes from the ABI verification I added in earlier commits.
(cherry picked from commit ff1cbea576)
I just renamed a few variables and eliminated a bunch of unnecessary
indentation.
Just to make it easier to review the actual functional change.
(cherry picked from commit 634435d8cf)
I think this was just an oversight. There is really no reason that this should
not match the rest of the SILVerifier w here we have moved from using #ifndef
NDEBUG to verificationEnabled checking.
(cherry picked from commit e25c664c98)
Also, make it more tolerant to instructions and builtins, which are not explicitly handled.
This avoids crashes when new instructions are added. We got lucky that this didn't happen so far.
Inlinability doesn’t affect the mangling except in function specializations, which are applied after the fact and should never mangle in information from an ABI-only decl. That means we can simply ban these from `@abi` instead of inferring them.
Also adds some assertions to help double-check that SIL never tries to directly mangle or retrieve inlinability info from an ABI-only decl.
Some notes:
1. In most cases, I think we were getting lucky with this by just inferring the
closure's isolation from its decl context. In the specific case that we were
looking at here, this was not true since we are returning from an @concurrent
async function a nonisolated(nonsending) method that closes over self. This
occurs since even when NonisolatedNonsendingByDefault we want to start importing
objc async functions as nonisolated(nonsending).
2. I also discovered that in the ActorIsolationChecker we were not visiting the
inner autoclosure meaning that we never set the ActorIsolation field on the
closure. After some discussion with @xedin about potentially visiting the
function in the ActorIsolationChecker, we came to the conclusion that this was
likely to result in source stability changes. So we put in a targeted fix just
for autoclosures in this specific case by setting their actor isolation in the
type checker.
3. Beyond adding tests to objc_async_from_swift to make sure that when
NonisolatedNonsendingByDefault is disabled we do the right thing, I noticed that
we did not have any tests that actually tested the behavior around
objc_async_from_swift when NonisolatedNonsendingByDefault is enabled. So I added
the relevant test lines so we can be sure that we get correct behavior in such a
case.
rdar://150209093
(cherry picked from commit ced96aa5cd)
In case of ObjectiveC classes, the runtime type can differ from its declared type.
Therefore a cast between (compile-time) unrelated classes may succeed at runtime.
rdar://149810124
Similarly to how https://github.com/swiftlang/swift/pull/70564 configures 'ClangImporter's 'CodeGenerator' using Swift's compilation target triple, we must use the versioned version of the 'isWeakImported' query to determine linkage for imported Clang symbols.
I made a mistake in 47156e006b. There was a
call to call to forAbstract() in SILTypeSubstituter that passed in the
wrong subject ype.
This call was inside SILTypeSubstituter's own implementation of replacing
opaque types with underlying types in a substitution map. This duplicates
an existing utility method in SubstitutionMap anyway, so let's just use
that instead.
Fixes rdar://149353285.
