Previously SILModule contained two different pathways for the deserializer to
send notifications that it had created functions:
1. A list of function pointers that were called when a function's body was
deserialized. This was added recently so that access enforcement elimination is
run on newly deserialized SIL code if we have already eliminated access
enforcement from the module.
2. SILModule::SerializationCallback. This is an implementation of the full
callback interface and is used by the SILModule to update linkage and other
sorts of book keeping.
To fix the pass manager notification infrastructure, I need to be able to send
notifications to a SILPassManager when deserializing. I also need to be able to
eliminate these callbacks when a SILPassManager is destroyed. These requirements
are incompatible with the current two implementations since: (2) is an
implementation detail of SILModule and (1) only notifies on function bodies
being deserialized instead of the creation of new declarations (what the caller
analysis wants).
Rather than adding a third group of callbacks, this commit refactors the
infrastructure in such a way that all of these use cases can use one
implementation. This is done by:
1. Lifting the interface of SerializedSILLoader::Callback into a base
notification protocol for deserialization called
DeserializationNotificationHandlerBase and its base no-op implementation into an
implementation of the aforementioned protocol:
DeserializationNotificationHandler.
2. Changing SILModule::SerializationCallback to implement
DeserializationNotificationHandler.
3. Creating a class called FunctionBodyDeserializationNotificationHandler that
takes in a function pointer and uses that to just override the
didDeserializeFunctionBody. This eliminates the need for the specific function
body deserialization list.
4. Replacing the state associated with the two other pathways with a single
DeserializationNotificationHandlerSet class that contains a set of
DeserializationNotificationHandler and chains notifications to them. This set
implements DeserializationNotificationHandlerBase so we know that its
implementation will always be in sync with DeserializationNotificationHandler.
rdar://42301529
ConvertFunction and reabstraction thunks need this attribute. Otherwise,
there is no way to identify that withoutActuallyEscaping was used
to explicitly perform a conversion.
The destination of a [without_actually_escaping] conversion always has
an escaping function type. The source may have either an escaping or
@noescape function type. The conversion itself may be a nop, and there
is nothing distinctive about it. The thing that is special about these
conversions is that the source function type may have unboxed
captures. i.e. they have @inout_aliasable parameters. Exclusivity
requires that the compiler enforce a SIL data flow invariant that
nonescaping closures with unboxed captures can never be stored or
passed as an @escaping function argument. Adding this attribute allows
the compiler to enforce the invariant in general with an escape hatch
for withoutActuallyEscaping.
This allowed me to fold all of the weird direct calls to createFunction into a
singular SILSerializationFunctionBuilder::createDeclaration. This is the only
API that is needed by the SILParser so only providing that gives us a
significantly cleaner API.
rdar://42301529
This commit does not modify those APIs or their usage. It just:
1. Moves the APIs onto SILFunctionBuilder and makes SILFunctionBuilder a friend
of SILModule.
2. Hides the APIs on SILModule so all users need to use SILFunctionBuilder to
create/destroy functions.
I am doing this in order to allow for adding/removing function notifications to
be enforced via the type system in the SILOptimizer. In the process of finishing
off CallerAnalysis for FSO, I discovered that we were not doing this everywhere
we need to. After considering various other options such as:
1. Verifying after all passes that the notifications were sent correctly and
asserting. Turned out to be expensive.
2. Putting a callback in SILModule. This would add an unnecessary virtual call.
I realized that by using a builder we can:
1. Enforce that users of SILFunctionBuilder can only construct composed function
builders by making the composed function builder's friends of
SILFunctionBuilder (notice I did not use the word subclass, I am talking
about a pure composition).
2. Refactor a huge amount of code in SILOpt/SILGen that involve function
creation onto a SILGenFunctionBuilder/SILOptFunctionBuilder struct. Many of
the SILFunction creation code in question are straight up copies of each
other with small variations. A builder would be a great way to simplify that
code.
3. Reduce the size of SILModule.cpp by 25% from ~30k -> ~23k making the whole
file easier to read.
NOTE: In this commit, I do not hide the constructor of SILFunctionBuilder since
I have not created the derived builder structs yet. Once I have created those in
a subsequent commit, I will hide that constructor.
rdar://42301529
print and parse as a stable hexadecimal form that isn't interpreted as UTF8.
One use case is in representing serialized protobuf strings (as in the
tensorflow branch: f7ed452eba/lib/SILOptimizer/Mandatory/TFPartition.cpp (L3875)).
The original work was done by @lattner and merged into the tensorflow
branch. This PR is to upstream those changes.
The other side of #17404. Since we don't want to generate up front key path metadata for properties/subscripts with no withheld implementation details, the client should generate a key path component that can be used to represent a key path component based on its public interface.
This is enough to let the test case in rdar://problem/40899824 pass,
and any callers of this function already need to be able to handle a
nullptr result. There's a lot more work to do in this area, but it's
nice to get the simple things working again.
Now that @inlinable is a supported feature, we need to handle cases
where a function is inlinable but it references some type that imports
differently in different Swift versions. To start, handle the case
where a SIL function's type is now invalid and therefore the entire
function can't be imported. This doesn't open up anything interesting
yet, but it's a start.
Part of rdar://problem/40899824
Client code can make a best effort at emitting a key path referencing a property with its publicly exposed API, which in the common case will match what the defining module would produce as the canonical key path component representation of the declaration. We can reduce the code size impact of these descriptors by not emitting them when there's no hidden or possibly-resiliently-changed-in-the-past information about a storage declaration, having the property descriptor symbol reference a sentinel value telling client key paths to use their definition of the key path component.
Upstream has renamed the DEBUG() macro to LLVM_DEBUG. This updates swift
accordingly:
$ find . -name \*.cpp -print -exec sed -i "" -E "s/ DEBUG\(/ LLVM_DEBUG(/g" {} \;
This flag supports promoting KeyPath access violations to an error in
Swift 4+, while building the standard library in Swift 3 mode. This is
only necessary as long as the standard library continues to build in
Swift 3 mode. Once the standard library build migrates, it can all be
ripped out.
<rdar://problem/40115738> [Exclusivity] Enforce Keypath access as an error, not a warning in 4.2.
