We could introduce non-nominal-type context descriptors, such as those for opaque declarations,
which are also interesting to be able to look up for reflection or remote purposes. This should be
a backward compatible change with old runtimes, which always ignore any context descriptor kind
they don't know about.
Non-generic classes with resilient ancestry do not have statically-emitted
metadata, so we can now emit an Objective-C resilient class stub instead.
Also, when emitting an Objective-C category, reference the class stub if
the class has resilient ancestry; previously this case would hit an assert.
Note that class stubs always start with a zero word, with the address point
pointing immediately after. This works around a linker issue, where the
linker tries to coalesce categories and gets confused upon encountering a
class stub.
This adds a new tail-allocated field to class context descriptors storing
a pointer to an Objective-C class stub.
When the stub is present, we use the new _objc_realizeClassFromSwift()
entry point to realize the class instead of calling objc_readClassPair().
This should attach categories to the realized class, if they were emitted
to reference the stub.
Recent Swift uses 2 as the is-Swift bit when running on newer versions, and 1 on older versions. Since it's difficult or impossible to know what we'll be running on at build time, make the selection at runtime.
The use of sizeof(void*) in TargetStructMetadata and
TargetEnumMetadata's accessors is incorrect when (e.g.) reading
metadata from a 32-bit process in a 64-bit host. Use
sizeof(StoredPointer) instead to properly account for the runtime
pointer size.
Fixes rdar://problem/47305557.
Translate the metadata for the generic requirements of an extension context
into a demangle tree that is associated with the demangling of an extension.
Teach the ASTDemangler how to handle class layout constraints as well.
With this, RemoteAST can resolve types nested within most constrained
extensions.
Read the extended context mangled name from an extension context descriptor
so we can form a proper demangle tree for extensions. For example, this allows
types nested within extensions of types from different modules to be found.
When an anonymous context descriptor provides a mangled name, use that
mangled name to provide the private declaration name for its child context.
This allows us to resolve private type names correctly when the corresponding
anonymous context has its mangled name.
Fixes rdar://problem/38231646.
When -enable-anonymous-context-mangled-names is provided, emit mangled
names as part of the metadata of an anonymous context. This will allow
us to match textual mangled names to the metadata.
This is a backward-compatible ABI extension. Part of rdar://problem/38231646/.
This is essentially a long-belated follow-up to Arnold's #12606.
The key observation here is that the enum-tag-single-payload witnesses
are strictly more powerful than the XI witnesses: you can simulate
the XI witnesses by using an extra case count that's <= the XI count.
Of course the result is less efficient than the XI witnesses, but
that's less important than overall code size, and we can work on
fast-paths for that.
The extra inhabitant count is stored in a 32-bit field (always present)
following the ValueWitnessFlags, which now occupy a fixed 32 bits.
This inflates non-XI VWTs on 32-bit targets by a word, but the net effect
on XI VWTs is to shrink them by two words, which is likely to be the
more important change. Also, being able to access the XI count directly
should be a nice win.
Use the elaborated type for the type alias that we are creating.
Because the type inherits from `TargetMetadata`, the reference here is
parsed as a reference to the underlying type in MSVC. Use the
elaborated type to resolve to the type itself. The rules for these
changed around C++11, but MSVC defaults to the old style of the name
resolution. NFC.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
IRGen always just emits a simple implementation that immediately
calls swift_relocateClassMetadata(); so allow the function to be
null in this case to save on code size.
Extend the key-path pattern with a representation of the generic environment
of the key-path, which includes the generic parameters and generic
requirements of the environment.
We should also allow references via manglings just to cover the
general case if we need it, but this is useful on its own so that
we can emit a reference to any natively-declared Swift type.
Previously, they would forward their unused spare bits to be used by other multi-payload enums, but
did not implement anything for single-payload extra inhabitants.
TargetGenericParamRef is a specialized structure used to describe the
subject of a generic requirement, e.g., the “T.Assoc” in “T.Assoc: P”.
Replace it with a mangled name, for several reasons:
1) Mangled type names are also fairly concise, can often be shared, and
are a well-tested path
2) Mangled type names can express any type, which might be useful in the
future
3) This structure doesn’t accommodate specifically stating where the
conformances come from (to extract associated type witnesses). Neither
can mangled names, but we’d like to do that work in only one place.
This change exposed an existing bug where we improperly calculated the
generic parameter counts for extensions of nested generic types. Fix that
bug here (which broke an execution test).
Runtime functions need to use the Swift calling convention for any function
returning MetadataResponse, so that we get the two values returned in separate
registers.
Fixes rdar://problem/45042971 and rdar://problem/45851050.
Witness table accessors return a witness table for a given type's
conformance to a protocol. They are called directly from IRGen
(when we need the witness table instance) and from runtime conformance
checking (swift_conformsToProtocol digs the access function out of the
protocol conformance record). They have two interesting functions:
1) For witness tables requiring instantiation, they call
swift_instantiateWitnessTable directly.
2) For synthesized witness tables that might not be unique, they call
swift_getForeignWitnessTable.
Extend swift_instantiateWitnessTable() to handle both runtime
uniquing (for #2) as well as handling witness tables that don't have
a "generic table", i.e., don't need any actual instantiation. Use it
as the universal entry point for "get a witness table given a specific
conformance descriptor and type", eliminating witness table accessors
entirely.
Make a few related simplifications:
* Drop the "pattern" from the generic witness table. Instead, store
the pattern in the main part of the conformance descriptor, always.
* Drop the "conformance kind" from the protocol conformance
descriptor, since it was only there to distinguish between witness
table (pattern) vs. witness table accessor.
* Internalize swift_getForeignWitnessTable(); IRGen no longer needs to
call it.
Reduces the code size of the standard library (+assertions build) by
~149k.
Addresses rdar://problem/45489388.
Add `@autoclosure` to parameter flags associated with
function type metadata, which makes it possible to correctly
round-trip mangled name <-> metadata of function types which
have parameters marked as `@autoclosure`.
Resolves: rdar://problem/45489901
Collapse the generic witness table, which was used only as a uniquing
data structure during witness table instantiation, into the protocol
conformance record. This colocates all of the constant protocol conformance
metadata and makes it possible for us to recover the generic witness table
from the conformance descriptor (including looking at the pattern itself).
Rename swift_getGenericWitnessTable() to swift_instantiateWitnessTable()
to make it clearer what its purpose is, and take the conformance descriptor
directly.
Place resilient witnesses in the protocol conformance descriptor,
tail-allocated after the conditional requirements, so they can be found by
reflection. Drop the resilient witness table and protocol descriptor from
the generic witness table.
Addresses rdar://problem/45228582.
Remove the compiler support for exclusivity warnings.
Leave runtime support for exclusivity warnings in non-release builds
only for unit testing convenience.
Remove a test case that checked the warning log output.
Modify test cases that relied on successful compilation in the
presence of exclusivity violations.
Fixes: <rdar://problem/45146046> Remaining -swift-version 3 tests for exclusivity
Have clients pass the requirement base descriptor to
swift_getAssociatedTypeWitness(), so that the witness index is just one
subtraction away, avoiding several dependent loads (witness table ->
conformance descriptor -> protocol descriptor -> requirement offset)
in the hot path.
The superclass descriptor reference in class context descriptors is only used
for metadata bound computations when the superclass is resilient. Only
include the superclass descriptor reference when the class has a resilient
superclass, using a trailing record. It’s a tiny space savings for
classes that don’t have resilient superclasses.
Encode default associated type witnesses using a sentinel prefix byte
(0xFF) in the mangled name rather than as a second low bit on the
reference. Align all of the mangled names used for type references to
2 bytes (so we get that low bit regardless) and separate the symbol
names for default associated type witnesses vs. other kinds of
metadata or reflection metadata.
