Start fixing SR-12526: `@derivative` attribute cross-module deserialization
crash. Remove original `AbstractFunctionDecl *` from `DerivativeAttr` and store
`DeclID` instead, mimicking `DynamicReplacementAttr`.
Type erasure requires a circular construction by its very nature:
@_typeEraser(AnyProto)
protocol Proto { /**/ }
public struct AnyProto : Proto {}
If we eagerly resolve AnyProto, the chain of resolution steps that
deserialization must make goes a little something like this:
Lookup(Proto)
-> Deserialize(@_typeEraser(AnyProto))
-> Lookup(AnyProto)
-> DeserializeInheritedStuff(AnyProto)
-> Lookup(Proto)
This cycle could be broken if the order of incremental inputs was
such that we had already cached the lookup of Proto.
Resolve this cycle in any case by suspending the deserialization of the
type eraser until the point it's demanded by adding
ResolveTypeEraserTypeRequest.
rdar://61270195
Previously, all witnesses of a `@differentiable` protocol requirement were
required to have the same attribute (or one with superset parameter indices).
However, this leads to many annotations on witnesses and is not ideal for
usability. `@differentiable` attributes are really only significant on
public witnesses, so that they are clearly `@differentiable` at a glance (in
source code, interface files, and API documentation), without looking through
protocol conformance hierarchies.
Now, only *public* witnesses of `@differentiable` protocol requirements are
required to have the same attribute (or one with superset parameter indices).
For less-visible witnesses, an implicit `@differentiable` attribute is created
with the same configuration as the requirement's.
Resolves TF-1117.
Upstreams #29771 from tensorflow branch.
Delete `@differentiable` attribute `jvp:` and `vjp:` arguments for derivative
registration. `@derivative` attribute is now the canonical way to register
derivatives.
Resolves TF-1001.
This commit refactors NameBinding.cpp virtually to the point of a rewrite. The goal is to make the import handling code process a struct containing information extracted from an ImportDecl, rather than the ImportDecl itself, so that a future commit can perform the same processing on imports that are not directly represented by an ImportDecl. The result takes more code, but it disentangles a knot of complicated logic into separate threads.
One semi-functional change is that validation of scoped imports (i.e. checking that the declaration actually exists) is now deferred until all of the file’s imports have been processed. Once cross-imports are supported, this will be necessary because scoped imports can select declarations from cross-import overlays, and the full set of cross-import overlays can’t be known until all imports have been seen.
Some comments refer to things that won’t exist until the next commit, like the visibleModules property. I’ll let you in on a litlte secret: I didn’t really do this all in one go.
This will be used for compiler-driven type erasure for dynamic
replacement of functions with an opaque return type. For now, just
parse the attribute and ignore it.
Add a platform kind and availability attributes for macCatalyst. macCatalyst
uses iOS version numbers and inherits availability from iOS attributes unless
a macCatalyst attribute is explicitly provided.
The `@differentiable` attribute marks a function as differentiable.
Example:
```
@differentiable(wrt: x, jvp: derivativeFoo where T: Differentiable)
func id<T>(_ x: T) -> T { x }
```
The `@differentiable` attribute has an optional `wrt:` clause specifying the
parameters that are differentiated "with respect to", i.e. the differentiability
parameters. The differentiability parameters must conform to the
`Differentiable` protocol.
If the `wrt:` clause is unspecified, the differentiability parameters are
currently inferred to be all parameters that conform to `Differentiable`.
The `@differentiable` attribute also has optional `jvp:` and `vjp:` labels
for registering derivative functions. These labels are deprecated in favor of
the `@derivative` attribute and will be removed soon.
The `@differentiable` attribute also has an optional `where` clause, specifying
extra differentiability requirements for generic functions.
The `@differentiable` attribute is gated by the
`-enable-experimental-differentiable-programming` flag.
Code changes:
- Add `DifferentiableAttributeTypeCheckRequest`.
- Currently, the request returns differentiability parameter indices, while
also resolving `JVPFunction`, `VJPFunction`, and
`DerivativeGenericSignature` and mutating them in-place in
`DifferentiableAttr`. This was the simplest approach that worked without
introducing request cycles.
- Add "is type-checked" bit to `DifferentiableAttr`.
- Alternatively, I tried changing `DifferentiableAttributeTypeCheckRequest` to
use `CacheKind::Cache` instead of `CacheKind::SeparatelyCached`, but it did
not seem to work: `@differentiable` attributes in non-primary-files were
left unchecked.
Type-checking rules (summary):
- `@differentiable` attribute must be declared on a function-like "original"
declaration: `func`, `init`, `subscript`, `var` (computed properties only).
- Parsed differentiability parameters must be valid (if they exist).
- Parsed `where` clause must be valid (if it exists).
- Differentiability parameters must all conform to `Differentiable`.
- Original result must all conform to `Differentiable`.
- If JVP/VJP functions are specified, they must match the expected type.
- `@differentiable(jvp:vjp:)` for derivative registration is deprecated in
favor of `@derivative` attribute, and will be removed soon.
- Duplicate `@differentiable` attributes with the same differentiability
parameters are invalid.
- For protocol requirements and class members with `@differentiable` attribute,
conforming types and subclasses must have the same `@differentiable` attribute
(or one with a superset of differentiability parameter indices) on
implementing/overriding declarations.
Store in `DifferentiableAttr` the original declaration on which the attribute
is declared.
The original declaration is resolved during parsing and deserialization
(not yet upstreamed).
Progress towards TF-828: upstream `@differentiable` attribute type-checking.
Enable qualified declaration names in `@derivative` attribute, just like
`@transpose` attribute.
`DerivativeAttr` now stores a base type `TypeRepr *`, which is non-null for
parsed attributes that reference a qualified original declaration.
Add `TypeResolutionFlags::AllowModule` flag to enable module lookup via
`TypeChecker::lookupMember` given a `ModuleType`.
Add tests for type-qualified and module-qualified declaration names.
Resolves TF-1058.
The `@transpose(of:)` attribute registers a function as a transpose of another
function. This patch adds the `@transpose(of:)` attribute definition, syntax,
parsing, and printing.
Resolves TF-827.
Todos:
- Type-checking (TF-830, TF-1060).
- Enable serialization (TF-838).
- Use module-qualified names instead of custom qualified name syntax/parsing
(TF-1066).
The `@derivative` attribute registers a function as a derivative of another
function-like declaration: a `func`, `init`, `subscript`, or `var` computed
property declaration.
The `@derivative` attribute also has an optional `wrt:` clause specifying the
parameters that are differentiated "with respect to", i.e. the differentiation
parameters. The differentiation parameters must conform to the `Differentiable`
protocol.
If the `wrt:` clause is unspecified, the differentiation parameters are inferred
to be all parameters that conform to `Differentiable`.
`@derivative` attribute type-checking verifies that the type of the derivative
function declaration is consistent with the type of the referenced original
declaration and the differentiation parameters.
The `@derivative` attribute is gated by the
`-enable-experimental-differentiable-programming` flag.
Resolves TF-829.
Replaces `ComponentIdentTypeRepr::getIdentifier()` and `getIdLoc()` with `getNameRef()` and `getNameLoc()`, which use `DeclName` and `DeclNameRef` respectively.
State the previously unstated nested type requirement that CodingKeys adds to the witness requirements of a given type. The goal is to make this member cheap to synthesize, and independent of the expensive protocol conformance checks required to append it to the member list.
Further, this makes a clean conceptual separation between what I'm calling "nested type requirements" and actual type and value requirements.
With luck, we'll never have to use this attribute anywhere else.
The `@derivative(of:)` attribute registers a function as a derivative of another
function. This patch adds the `@derivative(of:)` attribute definition, syntax,
parsing, and printing.
Resolves TF-826.
Todos:
- Type-checking (TF-829).
- Serialization (TF-837).
- Move `DifferentiableAttr` definition above `DeclAttributes` in
include/swift/AST/Attr.h, like other attributes.
- Remove unnecessary arguments from `DifferentiableAttr::DifferentiableAttr`
and `DifferentiableAttr::setDerivativeGenericSignature`.
- Add libSyntax test for `@differentiable` attributes.
We need this attribute to teach compiler to use a different name from the current
module name when generating runtime symbol names for a declaration. This is to serve
the workflow of refactoring a symbol from one library to another without breaking the existing
ABI.
This patch focuses on parsing and serializing the attribute, so @_originallyDefinedIn
will show up in AST, swiftinterface files and swiftmodule files.
rdar://55268186
This PR introduces `@differentiable` attribute to mark functions as differentiable. This PR only contains changes related to parsing the attribute. Type checking and other changes will be added in subsequent patches.
See https://github.com/apple/swift/pull/27506/files#diff-f3216f4188fd5ed34e1007e5a9c2490f for examples and tests for the new attribute.
Adds parsing for a type attribute `@differentiable`, which is optionally allowed to have argument `@differentiable(linear)`.
The typechecker currently rejects all uses of `@differentiable` with "error: attribute does not apply to type". Future work (https://bugs.swift.org/browse/TF-871https://bugs.swift.org/browse/TF-873) will update the typechecker to allow this attribute in places where it is allowed.
Resolves https://bugs.swift.org/browse/TF-822.
By convention, most structs and classes in the Swift compiler include a `dump()` method which prints debugging information. This method is meant to be called only from the debugger, but this means they’re often unused and may be eliminated from optimized binaries. On the other hand, some parts of the compiler call `dump()` methods directly despite them being intended as a pure debugging aid. clang supports attributes which can be used to avoid these problems, but they’re used very inconsistently across the compiler.
This commit adds `SWIFT_DEBUG_DUMP` and `SWIFT_DEBUG_DUMPER(<name>(<params>))` macros to declare `dump()` methods with the appropriate set of attributes and adopts this macro throughout the frontend. It does not pervasively adopt this macro in SILGen, SILOptimizer, or IRGen; these components use `dump()` methods in a different way where they’re frequently called from debugging code. Nor does it adopt it in runtime components like swiftRuntime and swiftReflection, because I’m a bit worried about size.
Despite the large number of files and lines affected, this change is NFC.
Structurally prevent a number of common anti-patterns involving generic
signatures by separating the interface into GenericSignature and the
implementation into GenericSignatureBase. In particular, this allows
the comparison operators to be deleted which forces callers to
canonicalize the signature or ask to compare pointers explicitly.
Adding ABIBreakingToAdd and other options for decl attribute kind isn't
sufficient because future attributes may forget to add the ABI/API impact bits.
This patch introduces the opposite options of these breaking bits (ABIStableToAdd, etc)
, and adds several static assertions to ensure one of the opposite ABI/API impact
flags is explicitly specified.
ABI/API checker used to hard-code whether adding or removing of a
decl attribute could break the existing ABI/API. This is not ideal because
new attributes may be added to AST without updating the checker. After this
change, new decl attribute could be specified whether it has ABI/API
impact and the checker could pick up the knowledge instantly.
