When a type (class, enum, or struct) is annotated @main, it is required
to provide a function with the following signature:
static func main() -> ()
That function will be called when the executable the type is defined
within is launched.
This simplifies fixing the master-next build. Upstream LLVM already
has a copy of this function, so on master-next we only need to delete
the Swift copy, reducing the potential for merge conflicts.
Make `SynthesizedFileUnit` attached to a `SourceFile`. This seemed like the
least ad-hoc approach to avoid doing unnecessary work for other `FileUnit`s.
TBDGen: when visiting a `SourceFile`, also visit its `SynthesizedFileUnit` if
it exists.
Serialization: do not treat `SynthesizedFileUnit` declarations as xrefs when
serializing the companion `SourceFile`.
Resolves TF-1239: AutoDiff test failures.
Add implicit declarations generated by the differentiation transform to a
`SynthesizedFileUnit` instead of an ad-hoc pre-existing `SourceFile`.
Resolves TF-1232: type reconstruction for AutoDiff-generated declarations.
Previously, type reconstruction failed because retroactively adding declarations
to a `SourceFile` did not update name lookup caches.
`SynthesizedFileUnit` is a container for synthesized declarations. Currently, it
only supports module-level declarations.
It is used by the SIL differentiation transform, which generates implicit struct
and enum declarations.
Convert most of the name lookup requests and a few other ancillary typechecking requests into dependency sinks.
Some requests are also combined sinks and sources in order to emulate the current scheme, which performs scope changes based on lookup flags. This is generally undesirable, since it means those requests cannot immediately be generalized to a purely context-based scheme because they depend on some client-provided entropy source. In particular, the few callers that are providing the "known private" name lookup flag need to be converted to perform lookups in the appropriate private context.
Clients that are passing "no known dependency" are currently considered universally incorrect and are outside the scope of the compatibility guarantees. This means that request-based dependency tracking registers strictly more edges than manual dependency tracking. It also means that once we fixup the clients that are passing "known private", we can completely remove these name lookup flags.
Finally, some tests had to change to accomodate the new scheme. Currently, we go out of our way to register a dependency edge for extensions that declare protocol conformances. However, we were also asserting in at least one test that extensions without protocol conformances weren't registering dependency edges. This is blatantly incorrect and has been undone now that the request-based scheme is automatically registering this edge.
Request-based incremental dependencies are enabled by default. For the time being, add a flag that will turn them off and switch back to manual dependency tracking.
Switch the direct operator lookup logic over to
querying the SourceLookupCache, then switch the
main operator lookup logic over to calling the
direct lookup logic rather than querying the
operator maps on the SourceFile.
This then allows us to remove the SourceFile
operator maps, in addition to the logic from
NameBinding that populated them. This requires
redeclaration checking to be implemented
separately.
Finally, to compensate for the caching that the old
operator maps were providing for imported results,
turn the operator lookup requests into cached
requests.
Query the SourceLookupCache for the operator decls,
and use ModuleDecl::getOperatorDecls for both
frontend stats and to clean up some code
completion logic.
In addition, this commit switches getPrecedenceGroups
over to querying SourceLookupCache.
A request is intended to be a pure function of its inputs. That function could, in theory, fail. In practice, there were basically no requests taking advantage of this ability - the few that were using it to explicitly detect cycles can just return reasonable defaults instead of forwarding the error on up the stack.
This is because cycles are checked by *the Evaluator*, and are unwound by the Evaluator.
Therefore, restore the idea that the evaluate functions are themselves pure, but keep the idea that *evaluation* of those requests may fail. This model enables the best of both worlds: we not only keep the evaluator flexible enough to handle future use cases like cancellation and diagnostic invalidation, but also request-based dependencies using the values computed at the evaluation points. These aforementioned use cases would use the llvm::Expected interface and the regular evaluation-point interface respectively.
Factor out the lookup side of TypeChecker::conformsToProtocol so we have
a dependency registration point available for evaluator-based
dependencies that doesn't have re-entrancy problems.
Introduce DirectOperatorLookupRequest &
DirectPrecedenceGroupLookupRequest that lookup
operator and precedence groups within a given
file or module without looking through imports.
These will eventually be used as the basis for the
new operator lookup implementation, but for now
just use them when querying lookup results from
serialized module files.
Turn macro metaprogramming into template metaprogramming by defining a new kind of request that runs operator lookups.
This is the final piece of the puzzle for requestification of the current referenced name tracker system.
If a cross-import overlay shadows another module and has a name starting with
'_', don't present that overlay in places where module name completions are
offered and present symbols comining from that module as if they came from
the shadowed module instead.
Resolves rdar://problem/59445688
We previously computed cross-imports by comparing N transitive imports against N transitive imports. This is wasteful, because at least one of the two modules in a pair has to actually declare a cross-import overlay for us to discover one, and the vast majority of modules don’t declare any.
This commit makes us instead compare N transitive imports against M transitive imports which are known to declare at least one cross-import overlay. Since N is potentailly in the thousands while M is perhaps in the double digits, this should be good for a substantial time savings.
However, this optimization has made a test of another cross-import performance optimization fail—not because we have regressed on that, but because it skips work the test case expects us to perform. I have XFAILed that test for now.
Fixes <rdar://problem/59538458>.
Add flags for whether delayed body parsing or #if
condition evaluation is disabled, as well as
whether warnings should be suppressed. Then pass
down these flags from the frontend.
This is in preparation for the requestification of
source file parsing where the SourceFile will need
to be able to parse itself on demand.
