* [IRGen+Runtime] Layout string getEnumTag for fixed size enums subset
getEnumTag impl for layout strings of fixed sized enums that use a function to fetch the enum tag
* Fix potential UB in IRGen
* [IRGen] Implement support for multi payload enums in layout strings
rdar://105837114
* Implement multi payload enum cases in swift_resolve_resilientAccessors
* Add missing const
* [IRGen] Handle complex single payload enum cases
rdar://110138498
Handles single payload enum cases with more complex bit patterns (e.g. >64 bits or scattered) by storing a relative pointer to a function that reads the tag.
* Use proper symbol for enum tag helper
* [IRGen] Support additional single payload enum cases in layout strings
rdar://105837101
Adds layout string support for single payload enums with simple (non-scattered) extra inhabitant patterns
* Add more test cases
* [IRGen] Make pointers to accessor functions in layout strings relative
rdar://106319336
Pointers embedded in static layout strings should always be relative, so layout strings can reside in read-only memory.
* Properly handle reference storage ownership
* Pass layout tag and metadata / type layout ppointers separately
* Layout string instantiation fully working
* Fix cases where hasLayoutString flag was not set when it should have
* Update include/swift/ABI/Metadata.h
* [IRGen] Add layout strings for generic and resilient types
rdar://105837048
* Add some corner cases
* Add flag to enable generic instantiation and some fixes
* Fix resilient types
* Fix metadata accessor function pointers in combined layout strings
