This results in wrong argument/return calling conventions.
First, the method call must be specialized. Only then the call can be de-virtualized.
Usually, it's done in this order anyway, because the `class_method` instruction is located before the `apply`.
But when inlining functions, the order (in the worklist) can be the other way round.
Fixes a compiler crash.
rdar://154631438
Originally, `FunctionWorklist` was a private utility in MandatoryPerformanceOptimizations.
Moved this to `Worklist.swift` to make it generally available.
Also, simplify the `pop()` function which changes the popping order - therefore some test changes were necessary.
The LeastValidPointerValue is hard-coded in the runtime.
Therefore this option is only available in embedded swift - which doesn't have a runtime.
rdar://151755654
When de-serializing a function and this function allocates a class, the methods of the de-serialized vtable must be handled, too.
Fixes an IRGen crash
rdar://152311945
This is important to get diagnostics for errors which are located in imported modules.
Such errors can sometimes only be detected when building the client module, because the error can be in a generic function which is specialized in the client module.
rdar://151162353
This changes the isIsolatingCurrentContext function to return `Bool?`
and removes all the witness table trickery we did previously to detect
if it was implemented or not. This comes at a cost of trying to invoke
it always, before `checkIsolated`, but it makes for an simpler
implementation and more checkable even by third party Swift code which
may want to ask this question.
Along with the `withSerialExecutor` function, this now enables us to
check the isolation at runtime when we have an `any Actor` e.g. from
`#isolation`.
Updates SE-0471 according to
https://forums.swift.org/t/se-0471-improved-custom-serialexecutor-isolation-checking-for-concurrency-runtime/78834/
review discussions
1. move embedded diagnostics out of the PerformanceDiagnostics pass. It was completely separated from the other logic in this pass, anyway.
2. rewrite it in swift
3. fix several bugs, that means: missed diagnostics, which led to IRGen crashes
* look at all methods in witness tables, including base protocols and associated conformances
* visit all functions in the call tree, including generic functions with class bound generic arguments
* handle all instructions, e.g. concurrency builtins
4. improve error messages by adding meaningful call-site information. For example:
* if the error is in a specialized function, report where the generic function is originally specialized with concrete types
* if the error is in a protocol witness method, report where the existential is created
For example:
```
protocol P: AnyObject {
func foo()
}
extension P {
func foo() {}
}
class C: P {}
let e: any P = C()
```
Such default methods are SILGen'd with a generic self argument. Therefore we need to specialize such witness methods, even if the conforming type is not generic.
rdar://145855851
Function types aren't always trivially copyable, e.g. with address-discriminated signed pointers on ARM64e. Introduce a function_cast helper and use that instead.
