This removes it from the AST and largely replaces it with AnyObject
at the SIL and IRGen layers. Some notes:
- Reflection still uses the notion of "unknown object" to mean an
object with unknown refcounting. There's no real reason to make
this different from AnyObject (an existential containing a
single object with unknown refcounting), but this way nothing
changes for clients of Reflection, and it's consistent with how
native objects are represented.
- The value witness table and reflection descriptor for AnyObject
use the mangling "BO" instead of "yXl".
- The demangler and remangler continue to support "BO" because it's
still in use as a type encoding, even if it's not an AST-level
Type anymore.
- Type-based alias analysis for Builtin.UnknownObject was incorrect,
so it's a good thing we weren't using it.
- Same with enum layout. (This one assumed UnknownObject never
referred to an Objective-C tagged pointer. That certainly wasn't how
we were using it!)
TypeRefBuilder and MetadataReader had nearly identical symbolic reference resolvers,
but diverged because TypeRefBuilder had its own local/remote address management mechanism,
and because TypeRefBuilder tries to resolve opaque types to their underlying types, whereas
other MetadataReader clients want to preserve them as written in source. The first problem
has been addressed by making TypeRefBuilder use `RemoteRef` everywhere, and the second
can be handled with a flag (and might be able to be handled more elegantly with some more
refactoring of general opaque type handling in MetadataReader).
Instead of passing around raw local pointers and references, and spreading
tricky offset arithmetic around with the Local/RemoteAddress fields in
ReflectionInfo, have the TypeRefBuilder code use RemoteRefs everywhere,
which keep the remote/local mapping together in one unit and provide
centralized API for this logic.
This doesn't yet change how code uses the RemoteRef address data to
follow pointers across objects, for things like reading type refs, but
that should be much easier to do after this lands.
These are now always zero, because memory readers handle virtual address mapping.
The `swift_reflection_info_t` structure used by the C RemoteMirror API keeps
its offset fields because it's supposed to be a stable API, but we now assert that
the values are always zero.
This reverts commit efaf1fbefa.
Add a much more palatable workaround for the unit tests. Rather than
adding the dllimport for the symbols, locally define the required
symbols. This list is sufficient to restore the ability to build tests
for Windows.
The runtime tests will statically link the runtime and dynamically link
to the standard library. This fails to build on Windows. This is a
horrible workaround for the time being.
Mangling these common types takes only two bytes, which is shorter than a symbolic reference. We
know where their metadata is in the standard library, too, so we don't need to search the lookup
tables for them.
This makes for a cleaner and less implicit-context-heavy API, and makes it easier for symbolic
reference resolvers to do context-dependent things (like map the in-memory base address back to a
remote address in MetadataReader).
The introduction of += and -= default implementations on
AdditiveArithmetic introduces an ambiguity with the += and -=
implementations on SIMD (where Scalar: FloatingPoint). Break the
ambiguity by adding another set of definitions of += and -= on
AdditiveArithmetic & SIMD where Self.Scalar: FloatingPoint.
Fixes rdar://problem/55278156.
When building swift as a part of LLVM (as opposed to standalone) the components
related to swift headers should explicitly depend on the clang target to produce
those. On LLVM 9 and up, that would be `clang-resource-headers` and on lower
versions it would be `clang-headers`. It is important that we check for
`clang-resource-headers` first because `clang-headers` refers to something
different in LLVM 9 and up.
We don't want objc_getClass and NSClassFromString to be able to feed arbitrary symbolic reference
pointers into the Swift runtime. Fixes rdar://problem/54724618.
Returns `true` if `T.Type` is known to refer to a concrete type. The
implementation allows for the optimizer to specialize this at -O and
eliminate conditional code.
Includes `Swift._isConcrete<T>(T.Type) -> Bool` wrapper function.
