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)
When performing a dynamic cast to an existential type that satisfies
(Metatype)Sendable, it is unsafe to allow isolated conformances of any
kind to satisfy protocol requirements for the existential. Identify
these cases and mark the corresponding cast instructions with a new flag,
`[prohibit_isolated_conformances]` that will be used to indicate to the
runtime that isolated conformances need to be rejected.
I am doing this in preparation for adding the ability to represent in the SIL
type system that a function is global actor isolated. Since we have isolated
parameters in SIL, we do not need to represent parameter, nonisolated, or
nonisolated caller in the type system. So this should be sufficient for our
purposes.
I am adding this since I need to ensure that we mangle into thunks that convert
execution(caller) functions to `global actor` functions what the global actor
is. Otherwise, we cannot tell the difference in between such a thunk and a thunk
that converts execution(caller) to execution(concurrent).
With this approach, you cannot tell whether a parameter is addressable only
from the function type. Instead you need the SILValue that will be passed to the
call site.
Preserve conditionallyAddressableParamIndices independent of any
addressableParamIndices. The conditional dependencies are subject to change
based on type substitution.
The Protocol field isn't really necessary, because the conformance
stores the protocol. But we do need the substituted subject type
of the requirement, just temporarily, until an abstract conformance
stores its own subject type too.
* let `SIL.Type` conform to `TypeProperties` to share the implementation of common type properties between the AST types and `SIL.Type`
* call references to an `AST.Type` `rawType` (instead of just `type`)
* remove unneeded stuff
* add comments
The `unchecked_ref_cast` is designed to be able to cast between
`Optional<ClassType>` and `ClassType`. We need to handle these cases by
checking if the type is optional and adjust the path accordingly.
* factor out common methods of AST Type/CanonicalType into a `TypeProperties` protocol.
* add more APIs to AST Type/CanoncialType.
* move `MetatypeRepresentation` from SIL.Type to AST.Type and implement it with a swift enum.
* let `Builder.createMetatype` get a CanonicalType as instance type, because the instance type must not be a lowered type.
The optional C++ type was bridged to a non-optional Swift type.
The correct way is to bridged the non-optional C++ type to the non-optional Swift type.
* getting the formal source and target types of casts
* `isFromVarDecl` and `usesMoveableValueDebugInfo` for AllocStackInst
* WitnessMethod APIs
* `TryApply.isNonAsync`
Check if an operand's instruction has been deleted in `UseList.next()`.
This allows to delete an instruction, which has two uses of a value, during use-list iteration.
This is necessary to fix a recent OSSA bug that breaks common occurrences on
mark_dependence [nonescaping]. Rather than reverting that change above, we make
forward progress toward implicit borrows scopes, as was the original intention.
In the near future, all InteriorPointer instructions will create an implicit
borrow scope. This means we have the option of not emitting extraneous
begin/end_borrow instructions around intructions like ref_element_addr,
open_existential, and project_box. After that, we can also migrate
GuaranteedForwarding instructions like tuple_extract and struct_extract.
We use the formal source type do decide whether a checked_cast_br is
known to succeed/fail. If we don't update it we loose that optimization
That is:
```
checked_cast_br AnyObject in %2 : X to X, bb1, bb2
```
Will not be simplified even though the operand and the destintation type
matches.
And move the implementation of `SIL.Type.canBeClass` to the AST Type. The SIL Type just calls the AST Type implementation.
Also rename `SIL.Type.canonicalASTType` -> `SIL.Type.astType`.
