More Sema cleanup

include/swift/AST/Decl.h

@@ -458,8 +458,12 @@ class alignas(1 << DeclAlignInBits) Decl {
 
     /// Whether there is are lazily-loaded conformances for this nominal type.
     unsigned HasLazyConformances : 1;
+
+    /// Whether we have already validated all members of the type that
+    /// affect layout.
+    unsigned HasValidatedLayout : 1;
   };
-  enum { NumNominalTypeDeclBits = NumGenericTypeDeclBits + 3 };
+  enum { NumNominalTypeDeclBits = NumGenericTypeDeclBits + 4 };
   static_assert(NumNominalTypeDeclBits <= 32, "fits in an unsigned");
 
   class ProtocolDeclBitfields {
@@ -2817,6 +2821,7 @@ class NominalTypeDecl : public GenericTypeDecl, public IterableDeclContext {
     NominalTypeDeclBits.AddedImplicitInitializers = false;
     ExtensionGeneration = 0;
     NominalTypeDeclBits.HasLazyConformances = false;
+    NominalTypeDeclBits.HasValidatedLayout = false;
   }
 
   friend class ProtocolType;
@@ -2859,11 +2864,23 @@ class NominalTypeDecl : public GenericTypeDecl, public IterableDeclContext {
     return NominalTypeDeclBits.AddedImplicitInitializers;
   }
 
-  /// Note that we have attempted to
+  /// Note that we have attempted to add implicit initializers.
   void setAddedImplicitInitializers() {
     NominalTypeDeclBits.AddedImplicitInitializers = true;
   }
-
+
+  /// Determine whether we have already validated any members
+  /// which affect layout.
+  bool hasValidatedLayout() const {
+    return NominalTypeDeclBits.HasValidatedLayout;
+  }
+
+  /// Note that we have attempted to validate any members
+  /// which affect layout.
+  void setHasValidatedLayout() {
+    NominalTypeDeclBits.HasValidatedLayout = true;
+  }
+
   /// Compute the type of this nominal type.
   void computeType();
 

lib/Sema/TypeCheckDecl.cpp

@@ -7891,7 +7891,11 @@ static bool shouldValidateMemberDuringFinalization(NominalTypeDecl *nominal,
 }
 
 void TypeChecker::requestClassLayout(ClassDecl *classDecl) {
-  // FIXME: Check a flag in the class...
+  if (classDecl->hasValidatedLayout())
+    return;
+
+  classDecl->setHasValidatedLayout();
+
   if (isa<SourceFile>(classDecl->getModuleScopeContext()))
     DeclsToFinalize.insert(classDecl);
 }
@@ -8157,15 +8161,6 @@ checkExtensionGenericParams(TypeChecker &tc, ExtensionDecl *ext, Type type,
   return { env, extContextType };
 }
 
-// FIXME: In TypeChecker.cpp; only needed because LLDB creates
-// extensions of typealiases to unbound generic types, which is
-// ill-formed but convenient.
-namespace swift {
-GenericParamList *cloneGenericParams(ASTContext &ctx,
-                                     DeclContext *dc,
-                                     GenericParamList *fromParams);
-} // namespace swift
-
 void TypeChecker::validateExtension(ExtensionDecl *ext) {
   // If we're currently validating, or have already validated this extension,
   // there's nothing more to do now.

lib/Sema/TypeChecker.cpp

@@ -261,13 +261,11 @@ Type TypeChecker::lookupBoolType(const DeclContext *dc) {
   return *boolType;
 }
 
-namespace swift {
-
 /// Clone the given generic parameters in the given list. We don't need any
 /// of the requirements, because they will be inferred.
-GenericParamList *cloneGenericParams(ASTContext &ctx,
-                                     DeclContext *dc,
-                                     GenericParamList *fromParams) {
+static GenericParamList *cloneGenericParams(ASTContext &ctx,
+                                            DeclContext *dc,
+                                            GenericParamList *fromParams) {
   // Clone generic parameters.
   SmallVector<GenericTypeParamDecl *, 2> toGenericParams;
   for (auto fromGP : *fromParams) {
@@ -292,12 +290,6 @@ GenericParamList *cloneGenericParams(ASTContext &ctx,
 
   return toParams;
 }
-} // namespace swift
-
-// FIXME: total hack
-GenericParamList *createProtocolGenericParams(ASTContext &ctx,
-                                              ProtocolDecl *proto,
-                                              DeclContext *dc);
 
 static void bindExtensionDecl(ExtensionDecl *ED, TypeChecker &TC) {
   if (ED->getExtendedType())

lib/Sema/TypeChecker.h

@@ -741,12 +741,6 @@ class TypeChecker final : public LazyResolver {
   /// will need to compute captures for.
   std::vector<AnyFunctionRef> ClosuresWithUncomputedCaptures;
 
-  /// Describes an attempt to capture a local function.
-  struct LocalFunctionCapture {
-    FuncDecl *LocalFunction;
-    SourceLoc CaptureLoc;
-  };
-
   /// Local functions that have been captured before their definitions.
   ///
   /// We need this to guard against functions that would transitively capture