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)
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)
If the method is a default witness methods (`selfType` != nil) it has generic self type.
In this case the generic self parameter is at depth 0 and the actual generic parameters of the substitution map are at depth + 1, e.g:
```
@convention(witness_method: P) <τ_0_0><τ_1_0 where τ_0_0 : GenClass<τ_1_0>.T>
^ ^
self params of substitution map at depth + 1
```
* move it from the SIL to the AST module (where it belongs)
* change the signature of `diagnose` from `diagnose(location, .some_error)` to `diagnose(.some_error, at: location)`
* add an overload to allow passing a `SIL.Location` directly to `diagnose`
* add a `Diagnostic : Error` utility struct which allows throwing a `Diagnostic`
Store specialize witness tables in a separate lookup table in the module. This allows that for a normal conformance there can exist the original _and_ a specialized witness table.
Also, add a boolean property `isSpecialized` to `WitnessTable` which indicates whether the witness table is specialized or not.
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.
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
InteriorLiveness has a new "visitInnerUses" mode used by DestroyHoisting. That
mode may visit dependent values, which was not valid for noescape
closures. ClosureLifetimeFixup inserts destroys of noescape closures after the
destroys of the captures. So following such dependent value could result in an
apparent use-after-destroy. This causes DestroyHoisting to insert redundant
destroys.
Fix: InteriorUses will conservatively only follow dependent values if they are
escapable. Non-escapable values, like noescape closures are now considered
escapes of the original value that the non-escapable value depends on. This can
be improved in the future, but we may want to rewrite ClosureLifetimeFixup first.
Fixes the root cause of: rdar://146142041
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.
