'AnyDifferentiable' and 'AnyDerivative' should conform to 'CustomReflectable' to prevent leaking implementation details. The mirror should reflect its underlying value directly.
Resolves rdar://75496334.
Rename `move(along:)` to `move(by:)` based on the proposal feedback. The main argument for the change is that tangent vectors specify both a direction and a magnitude, whereas `along:` does not indicate that `self` is being moved by the specified magnitude.
Compiler:
- Add `Forward` and `Reverse` to `DifferentiabilityKind`.
- Expand `DifferentiabilityMask` in `ExtInfo` to 3 bits so that it now holds all 4 cases of `DifferentiabilityKind`.
- Parse `@differentiable(reverse)` and `@differentiable(_forward)` declaration attributes and type attributes.
- Emit a warning for `@differentiable` without `reverse`.
- Emit an error for `@differentiable(_forward)`.
- Rename `@differentiable(linear)` to `@differentiable(_linear)`.
- Make `@differentiable(reverse)` type lowering go through today's `@differentiable` code path. We will specialize it to reverse-mode in a follow-up patch.
ABI:
- Add `Forward` and `Reverse` to `FunctionMetadataDifferentiabilityKind`.
- Extend `TargetFunctionTypeFlags` by 1 bit to store the highest bit of differentiability kind (linear). Note that there is a 2-bit gap in `DifferentiabilityMask` which is reserved for `AsyncMask` and `ConcurrentMask`; `AsyncMask` is ABI-stable so we cannot change that.
_Differentiation module:
- Replace all occurrences of `@differentiable` with `@differentiable(reverse)`.
- Delete `_transpose(of:)`.
Resolves rdar://69980056.
`valueWithDerivative(of:)` and `valueWithGradient(of:)` are the curried version of `valueWithDerivative(at:in:)` and `valueWithGradient(at:in:)`, respectively. They are not included the proposal and are not being used by any client that I know of. This patch removes them.
This replaces swiftMSVCRT with swiftCRT. The big difference here is
that the `visualc` module is no longer imported nor exported. The
`visualc` module remains in use for a singular test wrt availability,
but this should effectively remove the need for the `visualc` module.
The difference between the MSVCRT and ucrt module was not well
understood by most. MSVCRT provided ucrt AND visualc, combining pieces
of the old MSVCRT and the newer ucrt. The ucrt module is what you
really wanted most of the time, however, would need to use MSVCRT for
the convenience aliases for type-generic math and the deprecated math
constants.
Unfortunately, we cannot shadow the `ucrt` module and create a Swift SDK
overlay for ucrt as that seems to result in circular dependencies when
processing the `_Concurrency` module.
Although this makes using the C library easier for most people, it has a
more important subtle change: it cleaves the dependency on visualc.
This means that this enables use of Swift without Visual Studio for the
singular purpose of providing 3 header files. Additionally, it removes
the need for the installation of 2 of the 4 support files. This greatly
simplifies the deployment process on Windows.
Make `Optional` conditionally conform to `Differentiable` when the `Wrapped` type does.
`Optional.TangentVector` is a wrapper around `Wrapped.TangentVector?`.
Also, fix `Array.TangentVector.zeroTangentVectorInitializer`.
Resolves TF-1301.
Clean up a few general patterns that are now obviated by canImport
This aligns more generally with the cleanup that the Swift Package
Manager has already done in their automated XCTest-plumbing tool in
apple/swift-package-manager#1826.
Fix `PullbackEmitter::getArrayAdjointElementBuffer` to always lookup
`Array.TangentVector.subscript` from the stdlib.
Resolves compiler crash when user code also defines
`Array.TangentVector.subscript`.
`partial_apply` can be rewritten to `thin_to_thick_function` only if the
specialized callee is `@convention(thin)`.
This condition is newly exercised by the differentiation transform:
`{JVP,VJP}Emitter::visitApplyInst` generates argument-less `partial_apply`
with `@convention(method)` callees.
Resolves SR-12732.
Add `Differentiable.withDerivative(_:)`, a "derivative surgery" API.
`Differentiable.withDerivative(_:)` is an identity function returning `self`.
It takes a closure and applies it to the derivative of the return value, in
contexts where the return value is differentiated with respect to.
- Remove unnecessary imports from test/AutoDiff/stdlib/simd.swift.
- Use platform-correct `Builtin` integer type in
`PullbackEmitter::getArrayAdjointElementBuffer`.
Previously, two conditions were necessary to enable differentiable programming:
- Using the `-enable-experimental-differentiable-programming` frontend flag.
- Importing the `_Differentiation` module.
Importing the `_Differentiation` module is the true condition because it
contains the required compiler-known `Differentiable` protocol. The frontend
flag is redundant and cumbersome.
Now, the frontend flag is removed.
Importing `_Differentiation` is the only condition.
* Add all [differential operators](https://github.com/apple/swift/blob/master/docs/DifferentiableProgramming.md#list-of-differential-operators).
* Add `withoutDerivative(at:)`, used for efficiently stopping the derivative propagation at a value and causing the derivative at the value to be zero.
* Add utility `differentiableFunction(from:)`, used for creating a `@differentiable` function from an original function and a derivative function.
Mostly work done by @marcrasi and @dan-zheng.
Partially resolves TF-843.
TODO:
* Add `AnyDerivative`.
* Add `Array.differentiableMap(_:)` and `differentiableReduce(_:_:)`.
Add test/AutoDiff/lit.local.cfg: run tests only when `differentiable_programming`
is enabled in lit. With this, individual tests no longer need
`REQUIRES: differentiable_programming`.
Move multi-functionality SIL tests from test/AutoDiff/SIL/Serialization to
test/AutoDiff/SIL.
Garden test filenames.