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
- Calls to variadic-generic protocol requirements weren't applying
substitutions properly, so expansion-sensitive types in the callee
signature weren't pairing properly with their expansions in the
caller.
- emitPackTransform had an over-destroy if the transformation function
actually emitted into the temporary element directly.
- There were some MV ownership assertions that were wrong, which
revealed that the corresponding code really didn't handle consuming/
borrowing mismatches properly at all.
- We were completely mishandled consuming packs.
Fixes#81002, #80995, and #81600.
Specifically:
1. When we convert a function to nonisolated(nonsending), we need to
make sure that in the thunk we hop upon return since nonisolated(nonsending)
functions are assumed to preserve the caller's isolation.
2. When we convert a function from nonisolated(nonsending), we need to
make sure that in the thunk we hop onto the actor that we are passing in as the
isolated parameter of the nonisolated(nonsending) function. This ensures that
the nonisolated(nonsending) function can assume that it is already on its
isolated parameter's actor at function entry.
rdar://155905383
SILGen thunks.
Also, I discovered that we don't apply nonisolated(nonsending) to
function types in the new mode. That's one for a different patch.
Fixes rdar://154401813
This ensures that when we generate the vtable thunk for a
nonisolated(nonsending) override (or vis-a-versa), we get the ABI correct. I
also added tests for all of the relevant cases for vtables that we check for
protocols.
rdar://151394209
(cherry picked from commit ef23f97071)
This involved cleaning up and generalizing the work from
f245389bb3. I followed the same approach: hide the
implicit parameter while we run things through translateArgument and friends and
then put it back in manually.
As an additional benefit, I think I found a good place to put FunctionIsolation
onto lowered AnyFunctionTypes that will not cause cycles in the evaluator since
it is done in TypeLowering.
rdar://148785846
(cherry picked from commit 04b845cc97)
Now that coroutine kind (and consequently ABI) for the accessors is
keyed off a SIL option, it's no longer possible to read whether a given
SILFunction arose from a read/modify coroutine just by checking its
coroutine kind. Regardless of ABI, read/modify coroutines may only
unwind (i.e. are only permitted not to "run to completion") if the
relevant experimental (soon to be deleted) feature is enabled.
Specifically:
1. I made it so that thunks from caller -> concurrent properly ignore the
isolated parameter of the thunk when calling the concurrent function.
rdar://148112362
2. I made it so that thunks from concurrent -> caller properly create a
Optional<any Actor>.none and pass that into the caller function.
rdar://148112384
3. I made it so that in cases where we are assigning an @Sendable caller to a
non-sendable caller variable, we allow for the conversion as long as the
parameters/results are sendable as well.
rdar://148112532
4. I made it so that when we generate a thunk from @execution(caller) ->
@GlobalActor, we mangle in @GlobalActor into the thunk.
rdar://148112569
5. I discovered that due to the way we handle function conversion expr/decl ref
expr, we were emitted two thunks when we assigned a global @caller function to a
local @caller variable. The result is that we would first cast from @caller ->
@concurrent and then back to @caller. The result of this would be that the
@caller function would always be called on the global queue.
rdar://148112646
I also added a bunch of basic tests as well that showed that this behavior was
broken.
This just ensures that all thunks are verified right when they are created. This
is necessary since some thunks do not go through function post processing.
This would make sure that async function types marked as `@execution(caller)`
have correct isolation.
Also defines all of the possible conversions to and from `caller`
isolated function types.
If the conformance generic signature fixes all generic parameters,
F.getForwardingSubstitutionMap() is empty. Instead, map the
replacement types of the substitution map into the generic
environment earlier, before we strip off a fully-concrete generic
signature.
When the CoroutineAccessors feature is enabled, `begin_apply`
instructions produce an additional result representing the allocation
done by the callee. Fix a couple of cases where this additional result
was not being handled.
This corresponds to the parameter-passing convention of the Itanium C++
ABI, in which the argument is passed indirectly and possibly modified,
but not destroyed, by the callee.
@in_cxx is handled the same way as @in in callers and @in_guaranteed in
callees. OwnershipModelEliminator emits the call to destroy_addr that is
needed to destroy the argument in the caller.
rdar://122707697
The reason why I am fixing this is that otherwise, we get a warning when one
creates an actor isolated closure and pass it into a task, e.x.:
```swift
@MainActor func test() {
// We would get a warning on the closure below saying that we are sending
// a closure that is MainActor isolated.
Task {
...
}
}
```
Create two versions of the following functions:
isConsumedParameter
isGuaranteedParameter
SILParameterInfo::isConsumed
SILParameterInfo::isGuaranteed
SILArgumentConvention::isOwnedConvention
SILArgumentConvention::isGuaranteedConvention
These changes will be needed when we add a new convention for
non-trivial C++ types as the functions will return different answers
depending on whether they are called for the caller or the callee. This
commit doesn't change any functionality.
This reverts commit aa5dddb952.
Fixes `preset=buildbot,tools=RA,stdlib=DA` CI job, which without this revert fails on `AutoDiff/SILGen/nil_coalescing.swift` test.
Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
[serialized_for_package] if Package CMO is enabled. The latter kind
allows a function to be serialized even if it contains loadable types,
if Package CMO is enabled. Renamed IsSerialized_t as SerializedKind_t.
The tri-state serialization kind requires validating inlinability
depending on the serialization kinds of callee vs caller; e.g. if the
callee is [serialized_for_package], the caller must be _not_ [serialized].
Renamed `hasValidLinkageForFragileInline` as `canBeInlinedIntoCaller`
that takes in its caller's SerializedKind as an argument. Another argument
`assumeFragileCaller` is also added to ensure that the calle sites of
this function know the caller is serialized unless it's called for SIL
inlining optimization passes.
The [serialized_for_package] attribute is allowed for SIL function, global var,
v-table, and witness-table.
Resolves rdar://128406520
We do this by pushing the conversion down to the emission of the
closure expression, then teaching closure emission to apply the isolation
to the closure. Ideally, we combine the isolation along with the rest of
the conversion peephole, but if necessary, we make sure we emit the
isolation.
The main piece that's still missing here is support for closures;
they actually mostly work, but they infer the wrong isolation for
actor-isolated closures (it's not expressed in the type, so obviously
they're non-isolated), so it's not really functional. We also have
a significant problem where reabstraction thunks collide incorrectly
because we don't mangle (or represent!) formal isolation into
SILFunctionType; that's another follow-up. Otherwise, I think SILGen
is working.
In preparation for inserting mark_dependence instructions for lifetime
dependencies early, immediately after SILGen. That will simplify the
implementation of borrowed arguments.
Marking them unresolved is needed to make OSSA verification
conservative until lifetime dependence diagnostics runs.
The thunk is a reabstraction thunk with a custom prolog that
has a runtime precondition check that makes sure that concurrent
environment where the thunk is run matches that of a global
actor associated with the thunked type.