Requestify the computation of the list of memberwise initialized properties.

Fixes rdar://110776763, a case where initialized stored properties
introduced by peer macros weren't working alongside declared stored
properties.

Author: DougGregor

include/swift/AST/Decl.h

@@ -3995,6 +3995,10 @@ class NominalTypeDecl : public GenericTypeDecl, public IterableDeclContext {
   /// this type.
   ArrayRef<VarDecl *> getInitAccessorProperties() const;
 
+  /// Return a collection of all properties that will be part of the memberwise
+  ///  initializer.
+  ArrayRef<VarDecl *> getMemberwiseInitProperties() const;
+  
   /// Establish a mapping between properties that could be iniitalized
   /// via other properties by means of init accessors. This mapping is
   /// one-to-many because we allow intersecting `initializes(...)`.

include/swift/AST/DeclContext.h

@@ -850,9 +850,23 @@ class IterableDeclContext {
     HasNestedClassDeclarations = 1;
   }
 
-  /// Retrieve the set of members in this context.
+  /// Retrieve the current set of members in this context.
+  ///
+  /// NOTE: This operation is an alias of \c getCurrentMembers() that is considered
+  /// deprecated. Most clients should not use this or \c getCurrentMembers(), but
+  /// instead should use one of the projections of members that provides a semantic
+  /// view, e.g., \c getParsedMembers(), \c getABIMembers(), \c getAllMembers(), and so
+  /// on.
   DeclRange getMembers() const;
 
+  /// Retrieve the current set of members in this context, without triggering the
+  /// creation of new members via code synthesis, macro expansion, etc.
+  ///
+  /// This operation should only be used in narrow places where any side-effect
+  /// producing operations have been done earlier. For the most part, this means that
+  /// it should only be used in the implementation of
+  DeclRange getCurrentMembers() const;
+
   /// Get the members that were syntactically present in the source code,
   /// and will not contain any members that are implicitly synthesized by
   /// the implementation.

include/swift/AST/TypeCheckRequests.h

@@ -1693,6 +1693,28 @@ class InitAccessorPropertiesRequest :
   bool isCached() const { return true; }
 };
 
+/// Request to obtain a list of properties that will be reflected in the parameters of a
+/// memberwise initializer.
+class MemberwiseInitPropertiesRequest :
+    public SimpleRequest<MemberwiseInitPropertiesRequest,
+                         ArrayRef<VarDecl *>(NominalTypeDecl *),
+                         RequestFlags::Cached> {
+public:
+  using SimpleRequest::SimpleRequest;
+
+private:
+  friend SimpleRequest;
+
+  ArrayRef<VarDecl *>
+  evaluate(Evaluator &evaluator, NominalTypeDecl *decl) const;
+
+  // Evaluation.
+  bool evaluate(Evaluator &evaluator, AbstractStorageDecl *decl) const;
+
+public:
+  bool isCached() const { return true; }
+};
+
 class HasStorageRequest :
     public SimpleRequest<HasStorageRequest,
                          bool(AbstractStorageDecl *),

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -312,6 +312,9 @@ SWIFT_REQUEST(TypeChecker, StoredPropertiesRequest,
 SWIFT_REQUEST(TypeChecker, InitAccessorPropertiesRequest,
               ArrayRef<VarDecl *>(NominalTypeDecl *),
               Cached, NoLocationInfo)
+SWIFT_REQUEST(TypeChecker, MemberwiseInitPropertiesRequest,
+              ArrayRef<VarDecl *>(NominalTypeDecl *),
+              Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, StructuralTypeRequest, Type(TypeAliasDecl *), Cached,
               NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, SuperclassTypeRequest,

include/swift/AST/TypeMemberVisitor.h

@@ -61,10 +61,7 @@ class TypeMemberVisitor : public DeclVisitor<ImplClass, RetTy> {
 
   /// A convenience method to visit all the members.
   void visitMembers(NominalTypeDecl *D) {
-    for (Decl *member : D->getMembers()) {
-      member->visitAuxiliaryDecls([&](Decl *decl) {
-        asImpl().visit(decl);
-      });
+    for (Decl *member : D->getAllMembers()) {
       asImpl().visit(member);
     }
   }

lib/AST/Decl.cpp

@@ -4920,6 +4920,16 @@ NominalTypeDecl::getInitAccessorProperties() const {
       {});
 }
 
+ArrayRef<VarDecl *>
+NominalTypeDecl::getMemberwiseInitProperties() const {
+  auto &ctx = getASTContext();
+  auto mutableThis = const_cast<NominalTypeDecl *>(this);
+  return evaluateOrDefault(
+      ctx.evaluator,
+      MemberwiseInitPropertiesRequest{mutableThis},
+      {});
+}
+
 void NominalTypeDecl::collectPropertiesInitializableByInitAccessors(
     std::multimap<VarDecl *, VarDecl *> &result) const {
   for (auto *property : getInitAccessorProperties()) {

lib/AST/DeclContext.cpp

@@ -920,6 +920,10 @@ DeclRange IterableDeclContext::getCurrentMembersWithoutLoading() const {
 }
 
 DeclRange IterableDeclContext::getMembers() const {
+  return getCurrentMembers();
+}
+
+DeclRange IterableDeclContext::getCurrentMembers() const {
   loadAllMembers();
 
   return getCurrentMembersWithoutLoading();

lib/Refactoring/Refactoring.cpp

@@ -3415,7 +3415,7 @@ collectMembersForInit(ResolvedCursorInfoPtr CursorInfo,
 
   SourceManager &SM = nominalDecl->getASTContext().SourceMgr;
 
-  for (auto member : nominalDecl->getMembers()) {
+  for (auto member : nominalDecl->getMemberwiseInitProperties()) {
     auto varDecl = dyn_cast<VarDecl>(member);
     if (!varDecl) {
       continue;

lib/SILGen/SILGenConstructor.cpp

@@ -406,7 +406,7 @@ static void emitImplicitValueConstructor(SILGenFunction &SGF,
       storedProperties.insert(properties.begin(), properties.end());
     }
 
-    for (auto *member : decl->getMembers()) {
+    for (auto *member : decl->getAllMembers()) {
       auto *field = dyn_cast<VarDecl>(member);
       if (!field)
         continue;

lib/Sema/CodeSynthesis.cpp

@@ -297,14 +297,7 @@ static ConstructorDecl *createImplicitConstructor(NominalTypeDecl *decl,
     std::multimap<VarDecl *, VarDecl *> initializedViaAccessor;
     decl->collectPropertiesInitializableByInitAccessors(initializedViaAccessor);
 
-    for (auto member : decl->getMembers()) {
-      auto var = dyn_cast<VarDecl>(member);
-      if (!var)
-        continue;
-
-      if (!var->isMemberwiseInitialized(/*preferDeclaredProperties=*/true))
-        continue;
-
+    for (auto var : decl->getMemberwiseInitProperties()) {
       if (initializedViaAccessor.count(var))
         continue;