swift234

Optimize the generated == function for enums.

Before it was done with a big switch statement, which remained a switch until the final code.
Now it's done by getting an integer index for both enums and just doing an integer compare.
This results in a simple compare in the final code.

Note that the == function is only generated for enums without payload. Getting the integer
index of such enums is a cheap operation.




Swift SVN r23129