Instead it is a bit on ParamDecl and SILParameterInfo. I preserve the consuming
behavior by making it so that the type checker changes the ParamSpecifier to
ImplicitlyCopyableConsuming if we have a default param specifier and
transferring is set. NOTE: The user can never write ImplicitlyCopyableConsuming.
NOTE: I had to expand the amount of flags that can be stored in ParamDecl so I
stole bits from TypeRepr and added some logic for packing option bits into
TyRepr and DefaultValue.
rdar://121324715
Ad-hoc requirements are now obsolete by making `remoteCall`,
`record{Argument, ReturnType}`, `decodeNextArgument` protocols
requirements and injecting witness tables for `SerializationRequirement`
conformances during IRGen.
I thought that we would never actually hit this test case, but since we do not
have opaque values this pattern is treated like a projection in certain cases. I
updated the code as appropriate and added a test.
We should make this as a transfer... but this is just temporary until I get
around to it. For now this is always an out parameter, so we should be safe.
I was correct that it is lookthrough, but it has multiple parameters, so the
normal "baked" implementation cannot be used since the "baked" implementation
assumes that any insts it handles has a single operand.
I also made ref_to_unmanaged and unmanaged_to_ref look through. They should have
always been look through, but I believe early on they were marked assign and I
never touched fixed it. To get the test for strong_copy_unmanaged_value to work,
I needed them to obey these semantics so I fixed them at the same time.
Specifically, if we access a Sendable type from a ref_element_addr and the field
is mutable, we need to treat the use as a require since we could race on writing
to the field. If the field is a let though (and thus immutable), we can still
ignore it.
I also used this as an opportunity to add SIL tests for ref_element_addr.
This commit makes it so that we treat values captured by an actor isolated
closure as being transferred to that closure. I also introduced a new diagnostic
for these warnings that puts the main warning on the capture point of the value
so the user is able to see the actual capture that causes the transfer to occur:
```swift
nonisolated func testLocal2() async {
let l = NonSendableKlass()
// This is not safe since we use l later.
self.assumeIsolated { isolatedSelf in
isolatedSelf.ns = l
}
useValue(l) // expected-note {{access here could race}}
}
```
```
test.swift:74:14: warning: main actor-isolated closure captures value of non-Sendable type 'NonSendableKlass' from nonisolated context; later accesses to value could race
useValue(x) // expected-warning {{main actor-isolated closure captures value of non-Sendable type 'NonSendableKlass' from nonisolated context; later accesses to value could race}}
^
test.swift:76:12: note: access here could race
useValue(x) // expected-note {{access here could race}}
^
```
One thing to keep in mind is that if we have a function argument being captured
in this way, we still emit the "call site passes `self`" error. I am going to
begin cleaning that up in the next commit in this PR so that we emit a better
error here. But it makes sense to split these into two separate commits since
they are doing different things.
rdar://121345525