a fixed size of 16 bytes. 3 pointers is the magic value in
swift: many, many things are better if we can handle three
pointers efficiently.
Swift SVN r2147
type is either a protocol type or a protocol composition type. The
long form of this query returns the minimal set of protocol
declarations required by that existential type.
Use the new isExistentialType() everywhere that we previously checked
just for ProtocolType, implementing the appropriate rules. Among other
things, this includes:
- Type coercion
- Subtyping relationship
- Checking of explicit protocol conformance
- Member name lookup
Note the FIXME for IR generation; we need to decide how we want to
encode the witnesses for the different protocols.
This is most of <rdar://problem/11548207>.
Swift SVN r2086
swift_retain calls. The pertinent difference is that the former can be
marked nocapture, allowing general LLVM optimizations more flexibility.
With this change, early-cse is able to zap 9 more instructions, and 3
more functions are able to be marked nocapture by functionattrs in the
stdlib.
Swift SVN r2043
doesn't die if the same witness is required on multiple lines.
The right solution here is to find some way to re-use the
previous functions.
Swift SVN r1994
of protocol types to correctly handle self-assignment.
This ends up creating such a large amount of code that it's
worth extracting into its own helper function. Fortunately,
this can be the same helper function for every protocol type.
Swift SVN r1905
pointer TypeInfo more conveniently. Have this class return true for
isSingleRetainablePointer(). Further specialize the implementations
of the value witnesses so that we no longer ever require type-specific
witnesses for reference types.
Swift SVN r1900
value witnesses goes.
There are three major remaining things to do to support protocols:
- laying out the actual protocol members
- emitting witnesse for the actual protocol members
- detecting uses of the actual protocol members and funnelling
them through the witnesses as appropriate
All this work was just to let us treat protocol types as
first-class values.
Swift SVN r1899
