swift234

SILGen: Avoid using a stdlib function to get optional values.

When we've already established that the optional has a value, using unchecked_take_enum_data_addr to directly extract the enum payload is sufficient and avoids a redundant call and check at -Onone. Keep using the _getOptionalValue stdlib function for checked optional wrapping operations such as "x!", so that the stdlib can remain in control of trap handling policy.

The test/SIL/Serialization failures on the bot seem to be happening sporadically independent of this patch, and I can't reproduce failures in any configuration I've tried.

Swift SVN r22537