[AutoDiff] [stdlib] Rename 'Differentiable.TangentVector' to 'Derivative'

include/swift/AST/KnownIdentifiers.def

@@ -131,8 +131,8 @@ IDENTIFIER(zero)
 IDENTIFIER(Scalar)
 // Differentiable
 IDENTIFIER(AllDifferentiableVariables)
-IDENTIFIER(CotangentVector)
-IDENTIFIER(TangentVector)
+IDENTIFIER(Derivative)
+IDENTIFIER(Gradient)
 IDENTIFIER(allDifferentiableVariables)
 IDENTIFIER(moved)
 IDENTIFIER(tangentVector)

lib/AST/Type.cpp

@@ -4157,10 +4157,10 @@ Optional<VectorSpace> TypeBase::getAutoDiffAssociatedVectorSpace(
   Identifier associatedTypeIdentifier;
   switch (kind) {
   case AutoDiffAssociatedVectorSpaceKind::Tangent:
-    associatedTypeIdentifier = ctx.Id_TangentVector;
+    associatedTypeIdentifier = ctx.Id_Derivative;
     break;
   case AutoDiffAssociatedVectorSpaceKind::Cotangent:
-    associatedTypeIdentifier = ctx.Id_CotangentVector;
+    associatedTypeIdentifier = ctx.Id_Gradient;
     break;
   }
   auto associatedTypeLookup =

lib/Sema/DerivedConformanceDifferentiable.cpp

@@ -134,8 +134,8 @@ bool DerivedConformance::canDeriveDifferentiable(NominalTypeDecl *nominal,
   // Nominal type must not customize `TangentVector`, `CotangentVector`, or
   // `AllDifferentiableVariables` to anything other than `Self`.
   // Otherwise, synthesis is semantically unsupported.
-  auto tangentDecls = nominal->lookupDirect(C.Id_TangentVector);
-  auto cotangentDecls = nominal->lookupDirect(C.Id_CotangentVector);
+  auto tangentDecls = nominal->lookupDirect(C.Id_Derivative);
+  auto cotangentDecls = nominal->lookupDirect(C.Id_Gradient);
   auto allDiffableVarsDecls =
       nominal->lookupDirect(C.Id_AllDifferentiableVariables);
   auto nominalTypeInContext =
@@ -435,7 +435,7 @@ static ValueDecl *deriveDifferentiable_moved(DerivedConformance &derived) {
   auto parentDC = derived.getConformanceContext();
   auto selfInterfaceType = parentDC->getDeclaredInterfaceType();
 
-  auto *tangentDecl = getAssociatedStructDecl(parentDC, C.Id_TangentVector);
+  auto *tangentDecl = getAssociatedStructDecl(parentDC, C.Id_Derivative);
   auto tangentType = tangentDecl->getDeclaredInterfaceType();
 
   return deriveDifferentiable_method(
@@ -450,10 +450,10 @@ deriveDifferentiable_tangentVector(DerivedConformance &derived) {
   auto parentDC = derived.getConformanceContext();
   auto &C = derived.TC.Context;
 
-  auto *tangentDecl = getAssociatedStructDecl(parentDC, C.Id_TangentVector);
+  auto *tangentDecl = getAssociatedStructDecl(parentDC, C.Id_Derivative);
   auto tangentType = tangentDecl->getDeclaredInterfaceType();
 
-  auto *cotangentDecl = getAssociatedStructDecl(parentDC, C.Id_CotangentVector);
+  auto *cotangentDecl = getAssociatedStructDecl(parentDC, C.Id_Gradient);
   auto cotangentType = cotangentDecl->getDeclaredInterfaceType();
 
   return deriveDifferentiable_method(
@@ -657,7 +657,7 @@ getOrSynthesizeSingleAssociatedStruct(DerivedConformance &derived,
   auto nominal = derived.Nominal;
   auto &C = nominal->getASTContext();
 
-  assert(id == C.Id_TangentVector || id == C.Id_CotangentVector ||
+  assert(id == C.Id_Derivative || id == C.Id_Gradient ||
          id == C.Id_AllDifferentiableVariables);
 
   // If the associated struct already exists, return it.
@@ -689,7 +689,7 @@ getOrSynthesizeSingleAssociatedStruct(DerivedConformance &derived,
 
   // If the associated type is `TangentVector` or `CotangentVector`, make it
   // also conform to `AdditiveArithmetic`.
-  if (id == C.Id_TangentVector || id == C.Id_CotangentVector)
+  if (id == C.Id_Derivative || id == C.Id_Gradient)
     inherited.push_back(addArithType);
 
   // Associated struct can derive `AdditiveArithmetic` if the associated types
@@ -919,14 +919,14 @@ getOrSynthesizeAssociatedStructType(DerivedConformance &derived,
   bool freshlySynthesized = allDiffableVarsStructSynthesis.second;
 
   auto tangentStructSynthesis =
-      getOrSynthesizeSingleAssociatedStruct(derived, C.Id_TangentVector);
+      getOrSynthesizeSingleAssociatedStruct(derived, C.Id_Derivative);
   auto *tangentStruct = tangentStructSynthesis.first;
   if (!tangentStruct)
     return nullptr;
   freshlySynthesized |= tangentStructSynthesis.second;
 
   auto cotangentStructSynthesis =
-      getOrSynthesizeSingleAssociatedStruct(derived, C.Id_CotangentVector);
+      getOrSynthesizeSingleAssociatedStruct(derived, C.Id_Gradient);
   auto *cotangentStruct = cotangentStructSynthesis.first;
   if (!cotangentStruct)
     return nullptr;
@@ -940,18 +940,18 @@ getOrSynthesizeAssociatedStructType(DerivedConformance &derived,
     checkAndDiagnoseImplicitNoDerivative(TC, nominal, parentDC);
 
   // Add associated typealiases for structs.
-  addAssociatedTypeAliasDecl(C.Id_TangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Derivative,
                              tangentStruct, tangentStruct, TC);
-  addAssociatedTypeAliasDecl(C.Id_TangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Derivative,
                              cotangentStruct, cotangentStruct, TC);
-  addAssociatedTypeAliasDecl(C.Id_TangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Derivative,
                              allDiffableVarsStruct, tangentStruct, TC);
 
-  addAssociatedTypeAliasDecl(C.Id_CotangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Gradient,
                              tangentStruct, cotangentStruct, TC);
-  addAssociatedTypeAliasDecl(C.Id_CotangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Gradient,
                              cotangentStruct, tangentStruct, TC);
-  addAssociatedTypeAliasDecl(C.Id_CotangentVector,
+  addAssociatedTypeAliasDecl(C.Id_Gradient,
                              allDiffableVarsStruct, cotangentStruct, TC);
 
   addAssociatedTypeAliasDecl(C.Id_AllDifferentiableVariables,
@@ -983,9 +983,9 @@ getOrSynthesizeAssociatedStructType(DerivedConformance &derived,
 
   // Return the requested associated struct type.
   StructDecl *requestedStructDecl = nullptr;
-  if (id == C.Id_TangentVector)
+  if (id == C.Id_Derivative)
     requestedStructDecl = tangentStruct;
-  else if (id == C.Id_CotangentVector)
+  else if (id == C.Id_Gradient)
     requestedStructDecl = cotangentStruct;
   else if (id == C.Id_AllDifferentiableVariables)
     requestedStructDecl = allDiffableVarsStruct;
@@ -1074,9 +1074,9 @@ deriveDifferentiable_AssociatedStruct(DerivedConformance &derived,
   bool allMembersAssocTypesEqualsSelf =
       llvm::all_of(diffProperties, [&](VarDecl *member) {
         auto tangentType =
-            getAssociatedType(member, parentDC, C.Id_TangentVector);
+            getAssociatedType(member, parentDC, C.Id_Derivative);
         auto cotangentType =
-            getAssociatedType(member, parentDC, C.Id_CotangentVector);
+            getAssociatedType(member, parentDC, C.Id_Gradient);
         auto allDiffableVarsType =
             getAssociatedType(member, parentDC, C.Id_AllDifferentiableVariables);
         return tangentType->isEqual(cotangentType) &&
@@ -1106,13 +1106,13 @@ deriveDifferentiable_AssociatedStruct(DerivedConformance &derived,
       checkAndDiagnoseImplicitNoDerivative(TC, nominal, parentDC);
     addAssociatedTypeAliasDecl(C.Id_AllDifferentiableVariables,
         allDiffableVarsStruct, allDiffableVarsStruct, TC);
-    addAssociatedTypeAliasDecl(C.Id_TangentVector,
+    addAssociatedTypeAliasDecl(C.Id_Derivative,
         allDiffableVarsStruct, allDiffableVarsStruct, TC);
-    addAssociatedTypeAliasDecl(C.Id_CotangentVector,
+    addAssociatedTypeAliasDecl(C.Id_Gradient,
         allDiffableVarsStruct, allDiffableVarsStruct, TC);
-    addAssociatedTypeAliasDecl(C.Id_TangentVector,
+    addAssociatedTypeAliasDecl(C.Id_Derivative,
         parentDC, allDiffableVarsStruct, TC);
-    addAssociatedTypeAliasDecl(C.Id_CotangentVector,
+    addAssociatedTypeAliasDecl(C.Id_Gradient,
         parentDC, allDiffableVarsStruct, TC);
     TC.validateDecl(allDiffableVarsStruct);
     return parentDC->mapTypeIntoContext(
@@ -1135,12 +1135,12 @@ ValueDecl *DerivedConformance::deriveDifferentiable(ValueDecl *requirement) {
 }
 
 Type DerivedConformance::deriveDifferentiable(AssociatedTypeDecl *requirement) {
-  if (requirement->getBaseName() == TC.Context.Id_TangentVector)
+  if (requirement->getBaseName() == TC.Context.Id_Derivative)
     return deriveDifferentiable_AssociatedStruct(
-        *this, TC.Context.Id_TangentVector);
-  if (requirement->getBaseName() == TC.Context.Id_CotangentVector)
+        *this, TC.Context.Id_Derivative);
+  if (requirement->getBaseName() == TC.Context.Id_Gradient)
     return deriveDifferentiable_AssociatedStruct(
-        *this, TC.Context.Id_CotangentVector);
+        *this, TC.Context.Id_Gradient);
   if (requirement->getBaseName() == TC.Context.Id_AllDifferentiableVariables)
     return deriveDifferentiable_AssociatedStruct(
         *this, TC.Context.Id_AllDifferentiableVariables);

lib/Sema/DerivedConformances.cpp

@@ -326,11 +326,11 @@ ValueDecl *DerivedConformance::getDerivableRequirement(TypeChecker &tc,
       return getRequirement(KnownProtocolKind::KeyPathIterable);
 
     // SWIFT_ENABLE_TENSORFLOW
-    // Differentiable.TangentVector
-    // Differentiable.CotangentVector
+    // Differentiable.Derivative
+    // Differentiable.Gradient
     // Differentiable.AllDifferentiableVariables
-    if (name.isSimpleName(ctx.Id_TangentVector) ||
-        name.isSimpleName(ctx.Id_CotangentVector) ||
+    if (name.isSimpleName(ctx.Id_Derivative) ||
+        name.isSimpleName(ctx.Id_Gradient) ||
         name.isSimpleName(ctx.Id_AllDifferentiableVariables))
       return getRequirement(KnownProtocolKind::__Differentiable);
 

lib/Sema/TypeCheckAttr.cpp

@@ -3035,10 +3035,10 @@ void AttributeChecker::visitDifferentiatingAttr(DifferentiatingAttr *attr) {
   }
   if (funcResultElt.getName().str() == "differential") {
     kind = AutoDiffAssociatedFunctionKind::JVP;
-    autoDiffAssocTyId = ctx.Id_TangentVector;
+    autoDiffAssocTyId = ctx.Id_Derivative;
   } else if (funcResultElt.getName().str() == "pullback") {
     kind = AutoDiffAssociatedFunctionKind::VJP;
-    autoDiffAssocTyId = ctx.Id_CotangentVector;
+    autoDiffAssocTyId = ctx.Id_Derivative;
   } else {
     TC.diagnose(attr->getLocation(),
                 diag::differentiating_attr_expected_result_tuple_func_label);

stdlib/public/TensorFlow/Gradients.swift

@@ -48,29 +48,29 @@ public extension Differentiable {
   @inlinable
   func gradient<R : TensorFlowFloatingPoint>(
     in f: @differentiable (Self) -> Tensor<R>
-  ) -> CotangentVector {
+  ) -> Gradient {
     return self.pullback(in: f)(Tensor<R>(1))
   }
 
   @inlinable
   func valueWithGradient<R : TensorFlowFloatingPoint>(
     in f: @differentiable (Self) -> Tensor<R>
-  ) -> (value: Tensor<R>, gradient: CotangentVector) {
+  ) -> (value: Tensor<R>, gradient: Gradient) {
     let (y, pb) = self.valueWithPullback(in: f)
     return (y, pb(Tensor<R>(1)))
   }
 
   @inlinable
   func gradient<T : Differentiable, R : TensorFlowFloatingPoint>(
     at x: T, in f: @differentiable (Self, T) -> Tensor<R>
-  ) -> (CotangentVector, T.CotangentVector) {
+  ) -> (Gradient, T.Gradient) {
     return self.pullback(at: x, in: f)(Tensor<R>(1))
   }
 
   @inlinable
   func valueWithGradient<T : Differentiable, R : TensorFlowFloatingPoint>(
     at x: T, in f: @differentiable (Self, T) -> Tensor<R>
-  ) -> (value: Tensor<R>, gradient: (CotangentVector, T.CotangentVector)) {
+  ) -> (value: Tensor<R>, gradient: (Gradient, T.Gradient)) {
     let (y, pb) = self.valueWithPullback(at: x, in: f)
     return (y, pb(Tensor<R>(1)))
   }
@@ -85,7 +85,7 @@ public extension Differentiable {
 @inlinable
 public func valueWithGradient<T, R>(
   at x: T, in f: @differentiable (T) -> Tensor<R>
-) -> (value: Tensor<R>, gradient: T.CotangentVector)
+) -> (value: Tensor<R>, gradient: T.Gradient)
 where T : Differentiable, R : TensorFlowFloatingPoint {
   let (y, pullback) = valueWithPullback(at: x, in: f)
   return (y, pullback(Tensor<R>(1)))
@@ -94,7 +94,7 @@ where T : Differentiable, R : TensorFlowFloatingPoint {
 @inlinable
 public func valueWithGradient<T, U, R>(
   at x: T, _ y: U, in f: @differentiable (T, U) -> Tensor<R>
-) -> (value: Tensor<R>, gradient: (T.CotangentVector, U.CotangentVector))
+) -> (value: Tensor<R>, gradient: (T.Gradient, U.Gradient))
   where T : Differentiable, U : Differentiable,
         R : TensorFlowFloatingPoint {
   let (y, pullback) = valueWithPullback(at: x, y, in: f)
@@ -105,7 +105,7 @@ public func valueWithGradient<T, U, R>(
 public func valueWithGradient<T, U, V, R>(
   at x: T, _ y: U, _ z: V, in f: @differentiable (T, U, V) -> Tensor<R>
 ) -> (value: Tensor<R>,
-      gradient: (T.CotangentVector, U.CotangentVector, V.CotangentVector))
+      gradient: (T.Gradient, U.Gradient, V.Gradient))
   where T : Differentiable, U : Differentiable, V : Differentiable,
         R : TensorFlowFloatingPoint {
   let (y, pullback) = valueWithPullback(at: x, y, z, in: f)
@@ -117,7 +117,7 @@ public func valueWithGradient<T, U, V, R>(
 @inlinable
 public func valueWithGradient<T, R>(
   of f: @escaping @differentiable (T) -> Tensor<R>
-) -> (T) -> (value: Tensor<R>, gradient: T.CotangentVector)
+) -> (T) -> (value: Tensor<R>, gradient: T.Gradient)
   where T : Differentiable, R : TensorFlowFloatingPoint {
   return { x in valueWithGradient(at: x, in: f) }
 }
@@ -126,7 +126,7 @@ public func valueWithGradient<T, R>(
 public func valueWithGradient<T, U, R>(
   of f: @escaping @differentiable (T, U) -> Tensor<R>
 ) -> (T, U)
-    -> (value: Tensor<R>, gradient: (T.CotangentVector, U.CotangentVector))
+    -> (value: Tensor<R>, gradient: (T.Gradient, U.Gradient))
   where T : Differentiable, U : Differentiable,
         R : TensorFlowFloatingPoint {
   return { x, y in valueWithGradient(at: x, y, in: f) }
@@ -137,7 +137,7 @@ public func valueWithGradient<T, U, V, R>(
   of f: @escaping @differentiable (T, U, V) -> Tensor<R>
 ) -> (T, U, V)
     -> (value: Tensor<R>,
-        gradient: (T.CotangentVector, U.CotangentVector, V.CotangentVector))
+        gradient: (T.Gradient, U.Gradient, V.Gradient))
   where T : Differentiable, U : Differentiable, V : Differentiable,
         R : TensorFlowFloatingPoint {
   return { x, y, z in valueWithGradient(at: x, y, z, in: f) }
@@ -148,15 +148,15 @@ public func valueWithGradient<T, U, V, R>(
 @inlinable
 public func gradient<T, R>(
   at x: T, in f: @differentiable (T) -> Tensor<R>
-) -> T.CotangentVector
+) -> T.Gradient
   where T : Differentiable, R : TensorFlowFloatingPoint {
   return pullback(at: x, in: f)(Tensor<R>(1))
 }
 
 @inlinable
 public func gradient<T, U, R>(
   at x: T, _ y: U, in f: @differentiable (T, U) -> Tensor<R>
-) -> (T.CotangentVector, U.CotangentVector)
+) -> (T.Gradient, U.Gradient)
   where T : Differentiable, U : Differentiable,
         R : TensorFlowFloatingPoint {
   return pullback(at: x, y, in: f)(Tensor<R>(1))
@@ -165,7 +165,7 @@ public func gradient<T, U, R>(
 @inlinable
 public func gradient<T, U, V, R>(
   at x: T, _ y: U, _ z: V, in f: @differentiable (T, U, V) -> Tensor<R>
-) -> (T.CotangentVector, U.CotangentVector, V.CotangentVector)
+) -> (T.Gradient, U.Gradient, V.Gradient)
   where T : Differentiable, U : Differentiable, V : Differentiable,
         R : TensorFlowFloatingPoint {
   return pullback(at: x, y, z, in: f)(Tensor<R>(1))
@@ -176,15 +176,15 @@ public func gradient<T, U, V, R>(
 @inlinable
 public func gradient<T, R>(
   of f: @escaping @differentiable (T) -> Tensor<R>
-) -> (T) -> T.CotangentVector
+) -> (T) -> T.Gradient
   where T : Differentiable, R : TensorFlowFloatingPoint {
   return { x in gradient(at: x, in: f) }
 }
 
 @inlinable
 public func gradient<T, U, R>(
   of f: @escaping @differentiable (T, U) -> Tensor<R>
-) -> (T, U) -> (T.CotangentVector, U.CotangentVector)
+) -> (T, U) -> (T.Gradient, U.Gradient)
   where T : Differentiable, U : Differentiable,
         R : TensorFlowFloatingPoint {
   return { x, y in gradient(at: x, y, in: f) }
@@ -193,7 +193,7 @@ public func gradient<T, U, R>(
 @inlinable
 public func gradient<T, U, V, R>(
   of f: @escaping @differentiable (T, U, V) -> Tensor<R>
-) -> (T, U, V) -> (T.CotangentVector, U.CotangentVector, V.CotangentVector)
+) -> (T, U, V) -> (T.Gradient, U.Gradient, V.Gradient)
   where T : Differentiable, U : Differentiable, V : Differentiable,
         R : TensorFlowFloatingPoint {
   return { x, y, z in gradient(at: x, y, z, in: f) }

stdlib/public/TensorFlow/Ops.swift

@@ -120,11 +120,11 @@ extension Tensor : VectorNumeric where Scalar : Numeric {
 extension Tensor : ShapedVectorNumeric where Scalar : Numeric {}
 
 extension Tensor : Differentiable where Scalar : TensorFlowFloatingPoint {
-  public typealias TangentVector = Tensor
-  public typealias CotangentVector = Tensor
+  public typealias Derivative = Tensor
+  public typealias Gradient = Tensor
   public typealias AllDifferentiableVariables = Tensor
   @inlinable @inline(__always)
-  public func tangentVector(from cotangent: CotangentVector) -> TangentVector {
+  public func tangentVector(from cotangent: Gradient) -> Derivative {
     return cotangent
   }
 }