Preemptively rename @_versioned to @usableFromInline.

Author: dan-zheng

include/swift/AST/DiagnosticsSema.def

@@ -2439,8 +2439,8 @@ ERROR(differentiable_attr_forward_mode_unsupported,none,
       "forward-mode automatic differentiation is not supported yet", ())
 ERROR(differentiable_attr_invalid_access,none,
       "%select{adjoint|primal}2 %0 is required to either be public or "
-      "@_versioned because the original function %1 is public or @_versioned",
-      (DeclName, DeclName, bool))
+      "@usableFromInline because the original function %1 is public or "
+      "@usableFromInline", (DeclName, DeclName, bool))
 
 ERROR(compiler_evaluable_bad_context,none,
       "@compilerEvaluable functions not allowed here", ())

lib/Sema/TypeCheckAttr.cpp

@@ -2249,8 +2249,8 @@ void AttributeChecker::visitDifferentiableAttr(DifferentiableAttr *attr) {
   auto originalParamsTy = originalParams.getInterfaceType(ctx);
 
   // If the original function and the primal/adjoint have different parents, or
-  // if they both have no type context and are in different modules, then
-  // it's an error.
+  // if they both have no type context and are in different modules, then it's
+  // an error.
   // Returns true on error.
   std::function<bool(FuncDecl *)> hasValidTypeContext
     = [&](FuncDecl *func) {
@@ -2268,17 +2268,19 @@ void AttributeChecker::visitDifferentiableAttr(DifferentiableAttr *attr) {
     return original->getParent() == func->getParent();
   };
 
-  // If the original function is exported (i.e. it is public or @_versioned),
-  // then the primal/adjoint must also be exported.
+  // If the original function is exported (i.e. it is public or
+  // @usableFromInline), then the primal/adjoint must also be exported.
   // Returns true on error.
   using FuncSpecifier = DifferentiableAttr::FunctionSpecifier;
   auto checkAccessControl = [&](FuncDecl *func, FuncSpecifier funcSpec,
                                 bool isPrimal) {
-    auto originalAccess = original->getFormalAccess(/*useDC*/ nullptr,
-                                                    /*respectVersioned*/ true);
+    auto originalAccess =
+      original->getFormalAccess(/*useDC*/ nullptr,
+		                /*treatUsableFromInlineAsPublic*/ true);
     if (originalAccess < AccessLevel::Public) return false;
-    auto funcAccess = func->getFormalAccess(/*useDC*/ nullptr,
-                                            /*respectVersioned*/ true);
+    auto funcAccess =
+      func->getFormalAccess(/*useDC*/ nullptr,
+		            /*treatUsableFromInlineAsPublic*/ true);
     if (funcAccess >= AccessLevel::Public) return false;
     TC.diagnose(funcSpec.Loc.getBaseNameLoc(),
                 diag::differentiable_attr_invalid_access,

test/AutoDiff/differentiable_attr_access_control.swift

@@ -1,7 +1,7 @@
 // RUN: %target-swift-frontend -typecheck -verify %s
 
-// If the original function is "exported" (public or @_versioned), then its
-// primal/adjoint must also be exported.
+// If the original function is "exported" (public or @usableFromInline), then
+// its primal/adjoint must also be exported.
 
 // Ok: all public.
 @differentiable(reverse, adjoint: dfoo1(_:primal:seed:))
@@ -21,12 +21,12 @@ private func foo3(_ x: Float) -> Float { return 1 }
 private func dfoo3(_ x: Float, primal: Float, seed: Float) -> Float { return 1 }
 
 // Error: adjoint not exported.
-@differentiable(reverse, adjoint: dbar1(_:primal:seed:)) // expected-error {{adjoint 'dbar1(_:primal:seed:)' is required to either be public or @_versioned because the original function 'bar1' is public or @_versioned}}
+@differentiable(reverse, adjoint: dbar1(_:primal:seed:)) // expected-error {{adjoint 'dbar1(_:primal:seed:)' is required to either be public or @usableFromInline because the original function 'bar1' is public or @usableFromInline}}
 public func bar1(_ x: Float) -> Float { return 1 }
 private func dbar1(_ x: Float, primal: Float, seed: Float) -> Float { return 1 }
 
 // Error: primal not exported.
-@differentiable(reverse, primal: pbar2(_:), adjoint: dbar2(_:checkpoints:originalValue:seed:)) // expected-error {{primal 'pbar2' is required to either be public or @_versioned because the original function 'bar2' is public or @_versioned}}
+@differentiable(reverse, primal: pbar2(_:), adjoint: dbar2(_:checkpoints:originalValue:seed:)) // expected-error {{primal 'pbar2' is required to either be public or @usableFromInline because the original function 'bar2' is public or @usableFromInline}}
 @_versioned func bar2(_ x: Float) -> Float { return 1 }
 func pbar2(_ x: Float) -> (checkpoints: CheckpointsFoo, originalValue: Float) { return (CheckpointsFoo(), 1) }
 func dbar2(_ x: Float, checkpoints: CheckpointsFoo, originalValue: Float, seed: Float) -> Float { return 1 }