swift234

Extend SILModule with an API for linking of SILFunctions by their SILDeclRef.

Before, providing a full SILFunction declaration object with a proper SILType was the only way to link a function. And constructing such a SILFunction declaration by hand using low-level SIL APIs is very annoying and requires a lot of code to be written. This new linkFunction API allows for a lookup using SILDeclRef and essentially performs linking of a SILFunction by its mangled name (assuming this name is unique), which is much easier to invoke. The new API is useful, e.g. when you need to link a well-known function from a standard library.

Swift SVN r26252