swift234

[sil-cse] Fix a bug in the CSE of open_existential_ref instructions

When performing a CSE of open_existential_ref instructions, we replace the new archetype by the old archetype by cloning the uses and re-mapping the archetypes. But we also need to consider that some of the uses of a open_existential_ref instruction (e.g. loads) may produce results depending on the opened archetype being replaced. Therefore, for every such use its own uses (and their uses) should be eventually recursively cloned and type-remapped as well if they depend on the opened archetype being replaced.

Fixes rdar://28136015 and https://bugs.swift.org/browse/SR-2545