This includes global generic and non-generic global access
functions, protocol associated type access functions,
swift_getGenericMetadata, and generic type completion functions.
The main part of this change is that the functions now need to take
a MetadataRequest and return a MetadataResponse, which is capable
of expressing that the request can fail. The state of the returned
metadata is reported as an second, independent return value; this
allows the caller to easily check the possibility of failure without
having to mask it out from the returned metadata pointer, as well
as allowing it to be easily ignored.
Also, change metadata access functions to use swiftcc to ensure that
this return value is indeed returned in two separate registers.
Also, change protocol associated conformance access functions to use
swiftcc. This isn't really related, but for some reason it snuck in.
Since it's clearly the right thing to do, and since I really didn't
want to retroactively tease that back out from all the rest of the
test changes, I've left it in.
Also, change generic metadata access functions to either pass all
the generic arguments directly or pass them all indirectly. I don't
know how we ended up with the hybrid approach. I needed to change all
the code-generation and calls here anyway in order to pass the request
parameter, and I figured I might as well change the ABI to something
sensible.
I was trying to make the entry-delegation thing do *way* too much.
Just give the entry access to the lock/queue and introduce subclasses
which simplify most of the work.
Also, fix some bad reasoning around the attempts to avoid acquiring
locks in the absence of waiters. It really is always necessary to
acquire the lock when notifying; waiters cannot atomically set the
has-waiters flag and wait, so we have to protect against the
possibility that we notify before they can wait.
Now that every foreign type has a type context descriptor, we can use that for a uniquing key instead of a dedicated mangled string, saving some code size especially in code that makes heavy use of imported types. rdar://problem/37537241
The logic here is causing leaks in some situations, and it's likely we'll want
bridging calls to go back to +1 again anyway, so do the minimum adaptation to
the +0 convention for now.
rdar://34222540
Future Swifts may add new metadata kinds, so it isn't appropriate to crash when
we see one. In the case of reflection, we can fall back to opaque behavior.
rdar://34222540
The runtime hash table for protocol conformances is keyed by (type, protocol),
where the type can be either a type metadata pointer or a type context
descriptor. The latter is preferred for generic and resilient types, because
a single entry in the cache can work for any instantiation.
However, not all type metadata has a corresponding type context descriptor.
For example, a class that is dynamically subclassed by the Objective-C
runtime won't have a type context descriptor. In such cases, our key
into the hash table was (NULL, protocol) leading to mistaken
conformances for different dynamically-subclassed types.
Introduce a NULL check for the type of the hash table key, which
illustrates the problem in a number of existing tests that exercise
the runtime, and teach the runtime to use the type context descriptor
as the key only when it's non-NULL, falling back to the type metadata
pointer otherwise.
Fixes rdar://problem/38053213.
Change generic witness table instantiation to use a more lightweight
entry scheme that allocates the witness table as part of the entry.
In contrast, change generic metadata instantiation to use a more
straightforward allocation scheme where the metadata is a totally
independent allocation.
This is preparation for proper cyclic-dependency handling.
Check that an ``withoutActuallyEscaping(noescape_closure) { // scope}`` closure
has not escaped in the scope using the ``is_escaping_closure %closure``
instruction.
rdar://35525730
Will be used to verify that withoutActuallyEscaping's block does not
escape the closure.
``%escaping = is_escaping_closure %closure`` tests the reference count. If the
closure is not uniquely referenced it prints out and error message and
returns true. Otherwise, it returns false. The returned result can be
used with a ``cond_fail %escaping`` instruction to abort the program.
rdar://35525730
This regression wasn't caught by normal testing because the emission
pattern substantially changed anyway, breaking tests that were looking for
the field-offset vector, and because normal execution testing doesn't
actually use the field-offset vector and enum payload size fields.
Reflection, which does use these fields, was skating by for common types
because metadata is typically allocated out of freshly zeroed pages and
most such types have only one field.
Also, don't emit a completion function for value metadata with fixed layout.
We really shouldn't have to emit field-offset vectors for fixed-layout types;
the layout should just go in the type descriptor. But for now, this is what
we have to do.
