If the block is passed to another function - either as closure argument or as closure capture - it's "converted" to a swift closure with the help of a thunk. The thunk just calls the block.
If this is done with a non-escaping partial_apply, the block does not escape.
rdar://149095630
As SourceKit explicitly disables WMO, silence the diagnostic in this case (but leave it enabled for explicit non-WMO builds otherwise).
rdar://150596807
This utility is used by DependentAddressUseDefWalker which now conservatively
follows all possible uses. This could result in the same address being reached
multiple times during a def-use walk. Ensure that we don't infinitely recurse.
There is no small test case for this, but the fix is trivial and standard
practice for such walkers, and this is hit quickly in real usage, so there is no
danger of it regressing.
Fixes rdar://150403948 ([nonescapable] Infinite recursion compiler crash in
lifetime dependence checking)
(cherry picked from commit 4512927d2b)
Fix ownership issues with sequences of partial_apply's in AutoDiff closure specialization pass (#80662)
Each partial_apply consumes its arguments, therefore we should never release intermediate ones in the sequence of closures.
Fixes#78847
(cherry picked from commit 87ca0f8680)
Correctly generate dependency tracking for functions that return a non-Escapable
existential, such as:
func getMutableSpanWithOpaqueReturn(_ array: inout [Int]) -> any PAny & ~Copyable & ~Escapable
Previously, dependency insertion assumed that @out storage always initialized an
alloc_stack. But existentials are always boxed.
First, add a diagnostic to catch any missing dependency insertions now that
we're past the bootstrapping phase.
Then, generalize handling of dependency insertion to handle any access base as
long as it has a recognizable address source.
Fixes rdar://150388126 (Missing mark_dependence for opaque lifetime dependent
value)
(cherry picked from commit 9d8e8d3f05)
Array/ArraySlice/ContiguousArray have support for mutableSpan property.
These types are "optimized COW" types, we use compiler builtins begin_cow_mutation/end_cow_mutation to
optimize uniqueness checks. Since mutableSpan is a property and not a coroutine there is
no way to schedule the end_cow_mutaton operation at the end of the access.
This can lead to miscompiles in rare cases where we can end up using a stale storage buffer after a cow.
This PR inserts end_cow_mutation_addr to avoid this issue.
Note: We can end up with unnecessary end_cow_mutation_addr. But it is just a barrier to prevent invalid optimizations
and has no impact.
When a coroutine is extended because of a dependent lifetime, extend all scopes
that enclose that coroutine even if the coroutine itself has no lifetime
dependencies.
Fixes rdar://150275147 (Invalid SIL after lifetime dependence fixup involving
coroutines)
(cherry picked from commit 4a65be8074)
Add a note explaining that dependence on closure captures is not
supported. Otherwise, the diagnostics are very confusing:
"it depends on a closure capture; this is not yet supported"
(cherry picked from commit 83b0ce1098)
Ensure that we always issue a diagnostic on error, but avoid emitting any notes that don't have source locations.
With implicit accessors and thunks, report the correct line number and indicate which accessor generates the error.
Always check for debug_value users.
Consistently handle access scopes across diagnostic analysis and diagnostic messages.
(cherry picked from commit ec512864eb)
Fix a simple typo that results in infinite recursion on invalid code.
Fixes rdar://147470493 ([nonescapable] LifetimeDependenceInsertion: infinite
recursion in VariableUseDefWalker.walkup with immortal setter)
(cherry picked from commit c891d8ade4)
For example:
```
%0 = load %1
copy_addr %1 to %2
```
->
```
%0 = load %1
store %0 to %2
```
This is important for MandatoryRedundantLoadElimination to be able to create statically initialized globals in the mandatory pipeline.
For example:
```
public struct MyStruct {
public static let r: Range<Int> = 1 ..< 3
}
```
gets a statically initialized global, even at Onone, with this improvement.
rdar://149356742
Briefly (April 2025), RawSpan._extracting, Span._extracting, and UTF8Span.span
returned a borrowed value that depended on a copied argument. Continue to
support those interfaces. The implementations were correct but needed an
explicit _overrideLifetime.
(cherry picked from commit 8a48cd979b)
Diagnose a scoped dependence on an argument that inherits its lifetime as an
error:
@lifetime(borrow arg)
func reborrowSpan<T>(_ arg: Span<T>) -> Span<T> { arg }
@lifetime(copy span)
public func testBorrowInheritedArg<T>(_ span: Span<T>) -> Span<T> {
reborrowSpan(span) // expected-error {{lifetime-dependent value escapes its scope}}
}
Fixes: rdar://146319009 ([nonescapable] enforce borrow constraint narrowing of inherited lifetime)
(cherry picked from commit 4f470a1d34)
Add a case to LifetimeDependence.Scope to support dependencies on address-only
'let' variables. This comes up with C++ interop.
Fixes rdar://147500193 (Spurious lifetime error with closures)
(cherry picked from commit 5831777407)
This adds support to handle unsafe addressors, which generate mark_dependence
instructions with an address base. This case does not arise with lifetime
dependencies. Nonetheless, the lifetime dependence diagnostics kick in to
attempt to promote the unsafe addressor's mark_dependence to noescape, so we
need to handle it.
rdar://149784450 (Compiler crash with non-escapable deinit dereferencing)
(cherry picked from commit 3b08592ed2)
Allow a dependency on a local [read] access scope to be transfered to the
caller's [modify] access.
Fixes rdar://149560133 (Invalid lifetime dependence error when
trying to return Span from an inout argument)
(cherry picked from commit 33fbe11bf8)
Add support for returnValue phis (e.g. to return an Optional .some or .none).
Fixes rdar://149397018 (Wrapping non escapable in an Optional
(or any copy lifetime wrapper) is an escape)
(cherry picked from commit a1aaed9159)
Add support for extending owned temporary values in addition to access scopes
and borrow scopes. Required for _read accessors in which the coroutine depends
on an owned value.
(cherry picked from commit 62454f42fd)
We sometimes use LocalVariableUtils to analyze temporary storage in which the
store_borrow is not already enclosed by an access scope.
(cherry picked from commit 4e35d255ad)
Refactor VariableIntroducerUseDefWalker into a general
LifetimeDependenceUseDefWalker for use with LifetimeDependenceScopeFixup.
(cherry picked from commit b80bd16eea)
This allows further extension of access scopes.
Fixes rdar://143992296 (Use of `RawSpan` in switch context causes compiler crash
in AddressOwnershipLiveRange)
(cherry picked from commit c9279d9899)
This is only used for lifetime dependence diagnostics.
Fix a couple of obvious problems with data flow propagation that crept in during
"cleanup" because no unit tests existed.
(cherry picked from commit 37ecd0e9bd)
An address-type parameter may escape via an indirect argument if the function's
result depends on the argument's address.
(cherry picked from commit 05a9acbb40)
