swift_retain and objc_retain both handle nil already, so we can bypass the generic Optional value witnesses when instantiating Optional on a class type, which happens kind of a lot.
Swift SVN r23613
Generated code on x86_64 for swift_retain and swift_release and
swift_allocObject are unchanged. arm64 is improved by using weaker
memory barriers, fixing rdar://17423624.
Swift SVN r22887
instances of Swift subclasses of ObjC classes.
We were already doing this in the runtime. This patch
unhides the runtime's mask word (swift_isaMask) and makes
IR-gen take advantage of it when it can.
Swift SVN r21592
As part of the evolution toward a one-word array layout, create a type
that can be used to efficiently store Cocoa or Native class instances
and discriminate between them.
Swift SVN r21469
refcounting and take advantage of it.
Also, set the Swift1 flag in classes we generate.
Also, initialize a global cache of the non-pointer-isa
mask and use that instead of object_getClass, at least
within the runtime.
Also, centralize the runtime on a _swift_getSuperclass
function and make that use a direct access while we
await word from Greg on the desired ABI requirements.
Swift SVN r21077
This is the most general dynamic cast operation, permitting
arbitary source and destination types and handling arbitrary
changes in representation. A value of the destination type
is constructed in an address provided by the caller; flags
control the behavior w.r.t. the source value.
Not yet used; probably buggy in various particulars.
Swift SVN r18815
not an alignment value.
Assert that various entrypoints get an alignment mask.
Get everything uniformly passing an assertion about
dealloating an object with the correct allocation
size; don't actually enable the assertion yet, though.
rdar://16989632
Swift SVN r18550
