Disable stack promotion for classes with isolated deinit

[nickolas-pohilets]

This provides a proper fix of the issue, reverting workaround implemented in #76960

[ktoso]

@swift-ci please smoke test

[ktoso]

Hah, great observation, fix sounds good to me.

[eeckstein]

lgtm

[eeckstein]

Thinking about this again, a better fix would be to make this check in EscapeWalker.handleDestroy, because then it would also be correct for other optimizations which use EscapeInfo:

swift/SwiftCompilerSources/Sources/Optimizer/Utilities/EscapeUtils.swift

Line 598 in fc52e27

// The object to destroy (= the argument of the destructor) cannot escape itself.

Though, it's a bit more complicated because it also needs to handle structs/tuples/enums which contain a class reference. This can be done by adding a flag in TypeLowering.RecursiveProperties, like done for SILType::isOrContainsRawPointer (which is called by SIL.Type.isTrivialNonPointer).

[ktoso]

@eeckstein @nickolas-pohilets shall we merge this to resolve the crashes and investigate the follow up alternative approach you’re suggesting, or hold off merging and do the alternative approach instead immediately — wdyt @eeckstein?

[eeckstein]

I'm fine with merging this and doing it the right way in a follow-up. But it would be nice to first file a github issue and reference it in a to-do comment in the stack promotion