This will allow us to run two different completion kinds and deliver results from both of them.
Also: Compute a unified type context for global lookup. Previously, we always used the expected type context of the last lookup. But really, we should be considering all possible types from all constraint system solutions when computing code completion results from the cache.
Store whether a result is async in the `ContextFreeCodeCompletionResult` and determine whether an async method is used in a sync context when promoting the context free result to a contextual result.
rdar://78317170
Computing the type relation for every item in the code completion cache is way to expensive (~4x slowdown for global completion that imports `SwiftUI`). Instead, compute a type’s supertypes (protocol conformances and superclasses) once and write their USRs to the cache. To compute a type relation we can then check if the contextual type is in the completion item’s supertypes.
This reduces the overhead of computing the type relations (again global completion that imports `SwiftUI`) to ~6% – measured by instructions executed.
Technically, we might miss some conversions like
- retroactive conformances inside another module (because we can’t cache them if that other module isn’t imported)
- complex generic conversions (just too complicated to model using USRs)
Because of this, we never report an `unrelated` type relation for global items but always default to `unknown`.
But I believe this change covers the most common cases and is a good tradeoff between accuracy and performance.
rdar://83846531
Computing the type relation for every item in the code completion cache is way to expensive (~4x slowdown for global completion that imports `SwiftUI`). Instead, compute a type’s supertypes (protocol conformances and superclasses) once and write their USRs to the cache. To compute a type relation we can then check if the contextual type is in the completion item’s supertypes.
This reduces the overhead of computing the type relations (again global completion that imports `SwiftUI`) to ~6% – measured by instructions executed.
Technically, we might miss some conversions like
- retroactive conformances inside another module (because we can’t cache them if that other module isn’t imported)
- complex generic conversions (just too complicated to model using USRs)
Because of this, we never report an `unrelated` type relation for global items but always default to `unknown`.
But I believe this change covers the most common cases and is a good tradeoff between accuracy and performance.
rdar://83846531
