Sema: Use ExportedLevel for ExportContext services

Author: xymus

lib/Sema/TypeCheckAvailability.cpp

@@ -86,12 +86,12 @@ ExportContext::ExportContext(DeclContext *DC,
                              AvailabilityContext availability,
                              FragileFunctionKind kind,
                              llvm::SmallVectorImpl<UnsafeUse> *unsafeUses,
-                             bool spi, bool exported,
+                             bool spi, ExportedLevel exported,
                              bool implicit)
     : DC(DC), Availability(availability), FragileKind(kind),
       UnsafeUses(unsafeUses) {
   SPI = spi;
-  Exported = exported;
+  Exported = unsigned(exported);
   Implicit = implicit;
   Reason = unsigned(ExportabilityReason::General);
 }
@@ -178,7 +178,7 @@ ExportContext ExportContext::forDeclSignature(Decl *D) {
     computeExportContextBits(Ctx, D, &spi, &implicit);
   });
 
-  bool exported = ::isExported(D) != ExportedLevel::None;
+  ExportedLevel exported = ::isExported(D);
 
   return ExportContext(DC, availabilityContext, fragileKind, nullptr,
                        spi, exported, implicit);
@@ -194,7 +194,7 @@ ExportContext ExportContext::forFunctionBody(DeclContext *DC, SourceLoc loc) {
   forEachOuterDecl(
       DC, [&](Decl *D) { computeExportContextBits(Ctx, D, &spi, &implicit); });
 
-  bool exported = false;
+  ExportedLevel exported = ExportedLevel::None;
 
   return ExportContext(DC, availabilityContext, fragileKind, nullptr,
                        spi, exported, implicit);
@@ -205,8 +205,9 @@ ExportContext ExportContext::forConformance(DeclContext *DC,
   assert(isa<ExtensionDecl>(DC) || isa<NominalTypeDecl>(DC));
   auto where = forDeclSignature(DC->getInnermostDeclarationDeclContext());
 
-  where.Exported &= proto->getFormalAccessScope(
-      DC, /*usableFromInlineAsPublic*/true).isPublic();
+  if (!proto->getFormalAccessScope(
+        DC, /*usableFromInlineAsPublic*/true).isPublic())
+    where.Exported = unsigned(ExportedLevel::None);
 
   return where;
 }
@@ -219,7 +220,7 @@ ExportContext ExportContext::withReason(ExportabilityReason reason) const {
 
 ExportContext ExportContext::withExported(bool exported) const {
   auto copy = *this;
-  copy.Exported = isExported() && exported;
+  copy.Exported = exported ? Exported : unsigned(ExportedLevel::None);
   return copy;
 }
 

lib/Sema/TypeCheckAvailability.h

@@ -17,6 +17,7 @@
 #include "swift/AST/AvailabilityConstraint.h"
 #include "swift/AST/AvailabilityContext.h"
 #include "swift/AST/DeclContext.h"
+#include "swift/AST/DeclExportabilityVisitor.h"
 #include "swift/AST/Identifier.h"
 #include "swift/Basic/LLVM.h"
 #include "swift/Basic/OptionSet.h"
@@ -115,14 +116,14 @@ class ExportContext {
   FragileFunctionKind FragileKind;
   llvm::SmallVectorImpl<UnsafeUse> *UnsafeUses;
   unsigned SPI : 1;
-  unsigned Exported : 1;
+  unsigned Exported : 2;
   unsigned Implicit : 1;
   unsigned Reason : 3;
 
   ExportContext(DeclContext *DC, AvailabilityContext availability,
                 FragileFunctionKind kind,
                 llvm::SmallVectorImpl<UnsafeUse> *unsafeUses,
-                bool spi, bool exported, bool implicit);
+                bool spi, ExportedLevel exported, bool implicit);
 
 public:
 
@@ -184,9 +185,12 @@ class ExportContext {
   /// If true, the context is SPI and can reference SPI declarations.
   bool isSPI() const { return SPI; }
 
-  /// If true, the context is exported and cannot reference SPI declarations
-  /// or declarations from `@_implementationOnly` imports.
-  bool isExported() const { return Exported; }
+  /// If true, the context is exported explicitly and cannot reference
+  /// restricted decls.
+  bool isExported() const { return Exported != unsigned(ExportedLevel::None); }
+
+  /// Get the export level of the context.
+  ExportedLevel getExportedLevel() const { return ExportedLevel(Exported); }
 
   /// If true, the context can only reference exported declarations, either
   /// because it is the signature context of an exported declaration, or