Merge pull request #15201 from slavapestov/special-init-name

Use a special DeclBaseName for `init`

Author: slavapestov

include/swift/AST/Identifier.h

@@ -215,6 +215,7 @@ class DeclBaseName {
   enum class Kind: uint8_t {
     Normal,
     Subscript,
+    Constructor,
     Destructor
   };
 
@@ -224,6 +225,8 @@ class DeclBaseName {
   /// This is an implementation detail that should never leak outside of
   /// DeclName.
   static void *SubscriptIdentifierData;
+  /// As above, for special constructor DeclNames.
+  static void *ConstructorIdentifierData;
   /// As above, for special destructor DeclNames.
   static void *DestructorIdentifierData;
 
@@ -238,13 +241,19 @@ class DeclBaseName {
     return DeclBaseName(Identifier((const char *)SubscriptIdentifierData));
   }
 
+  static DeclBaseName createConstructor() {
+    return DeclBaseName(Identifier((const char *)ConstructorIdentifierData));
+  }
+
   static DeclBaseName createDestructor() {
     return DeclBaseName(Identifier((const char *)DestructorIdentifierData));
   }
 
   Kind getKind() const {
     if (Ident.get() == SubscriptIdentifierData) {
       return Kind::Subscript;
+    } else if (Ident.get() == ConstructorIdentifierData) {
+      return Kind::Constructor;
     } else if (Ident.get() == DestructorIdentifierData) {
         return Kind::Destructor;
     } else {
@@ -282,6 +291,8 @@ class DeclBaseName {
       return getIdentifier().str();
     case Kind::Subscript:
       return "subscript";
+    case Kind::Constructor:
+      return "init";
     case Kind::Destructor:
       return "deinit";
     }

include/swift/AST/KnownIdentifiers.def

@@ -61,7 +61,6 @@ IDENTIFIER(forKey)
 IDENTIFIER(from)
 IDENTIFIER(fromRaw)
 IDENTIFIER(hashValue)
-IDENTIFIER(init)
 IDENTIFIER(initialize)
 IDENTIFIER(initStorage)
 IDENTIFIER(initialValue)

include/swift/Parse/Parser.h

@@ -1427,7 +1427,8 @@ ParsedDeclName parseDeclName(StringRef name) LLVM_READONLY;
 DeclName formDeclName(ASTContext &ctx,
                       StringRef baseName,
                       ArrayRef<StringRef> argumentLabels,
-                      bool isFunctionName);
+                      bool isFunctionName,
+                      bool isInitializer);
 
 /// Parse a stringified Swift declaration name, e.g. "init(frame:)".
 DeclName parseDeclName(ASTContext &ctx, StringRef name);

include/swift/Serialization/ModuleFormat.h

@@ -55,7 +55,7 @@ const uint16_t VERSION_MAJOR = 0;
 /// describe what change you made. The content of this comment isn't important;
 /// it just ensures a conflict if two people change the module format.
 /// Don't worry about adhering to the 80-column limit for this line.
-const uint16_t VERSION_MINOR = 402; // Last change: effects(releasenone)
+const uint16_t VERSION_MINOR = 403; // Last change: `init` special name
 
 using DeclIDField = BCFixed<31>;
 
@@ -380,6 +380,7 @@ using OptionalTypeKindField = BCFixed<2>;
 enum class DeclNameKind: uint8_t {
   Normal,
   Subscript,
+  Constructor,
   Destructor
 };
 
@@ -394,6 +395,8 @@ enum SpecialIdentifierID : uint8_t {
   OBJC_HEADER_MODULE_ID,
   /// Special value for the special subscript name
   SUBSCRIPT_ID,
+  /// Special value for the special constructor name
+  CONSTRUCTOR_ID,
   /// Special value for the special destructor name
   DESTRUCTOR_ID,
 

lib/AST/Decl.cpp

@@ -2773,7 +2773,7 @@ void ClassDecl::addImplicitDestructor() {
 
 bool ClassDecl::hasMissingDesignatedInitializers() const {
   auto *mutableThis = const_cast<ClassDecl *>(this);
-  (void)mutableThis->lookupDirect(getASTContext().Id_init,
+  (void)mutableThis->lookupDirect(DeclBaseName::createConstructor(),
                                   /*ignoreNewExtensions*/true);
   return Bits.ClassDecl.HasMissingDesignatedInitializers;
 }
@@ -2821,11 +2821,10 @@ bool ClassDecl::inheritsSuperclassInitializers(LazyResolver *resolver) {
 
   // Look at all of the initializers of the subclass to gather the initializers
   // they override from the superclass.
-  auto &ctx = getASTContext();
   llvm::SmallPtrSet<ConstructorDecl *, 4> overriddenInits;
   if (resolver)
     resolver->resolveImplicitConstructors(this);
-  for (auto member : lookupDirect(ctx.Id_init)) {
+  for (auto member : lookupDirect(DeclBaseName::createConstructor())) {
     auto ctor = dyn_cast<ConstructorDecl>(member);
     if (!ctor)
       continue;
@@ -2855,7 +2854,7 @@ bool ClassDecl::inheritsSuperclassInitializers(LazyResolver *resolver) {
   // Note: This should be treated as a lookup for intra-module dependency
   // purposes, but a subclass already depends on its superclasses and any
   // extensions for many other reasons.
-  for (auto member : superclassDecl->lookupDirect(ctx.Id_init)) {
+  for (auto member : superclassDecl->lookupDirect(DeclBaseName::createConstructor())) {
     if (AvailableAttr::isUnavailable(member))
       continue;
 
@@ -5195,6 +5194,8 @@ ConstructorDecl::ConstructorDecl(DeclName Name, SourceLoc ConstructorLoc,
   Bits.ConstructorDecl.HasStubImplementation = 0;
   Bits.ConstructorDecl.InitKind = static_cast<unsigned>(CtorInitializerKind::Designated);
   Bits.ConstructorDecl.Failability = static_cast<unsigned>(Failability);
+
+  assert(Name.getBaseName() == DeclBaseName::createConstructor());
 }
 
 void ConstructorDecl::setParameterLists(ParamDecl *selfDecl,
@@ -5441,7 +5442,7 @@ ConstructorDecl::getDelegatingOrChainedInitKind(DiagnosticEngine *diags,
       } else if (auto *CRE = dyn_cast<ConstructorRefCallExpr>(Callee)) {
         arg = CRE->getArg();
       } else if (auto *dotExpr = dyn_cast<UnresolvedDotExpr>(Callee)) {
-        if (dotExpr->getName().getBaseName() != "init")
+        if (dotExpr->getName().getBaseName() != DeclBaseName::createConstructor())
           return { true, E };
 
         arg = dotExpr->getBase();

lib/AST/Identifier.cpp

@@ -22,6 +22,8 @@ using namespace swift;
 
 void *DeclBaseName::SubscriptIdentifierData =
     &DeclBaseName::SubscriptIdentifierData;
+void *DeclBaseName::ConstructorIdentifierData =
+    &DeclBaseName::ConstructorIdentifierData;
 void *DeclBaseName::DestructorIdentifierData =
     &DeclBaseName::DestructorIdentifierData;
 

lib/AST/NameLookup.cpp

@@ -83,7 +83,6 @@ bool swift::removeOverriddenDecls(SmallVectorImpl<ValueDecl*> &decls) {
   if (decls.empty())
     return false;
 
-  ASTContext &ctx = decls.front()->getASTContext();
   llvm::SmallPtrSet<ValueDecl*, 8> overridden;
   for (auto decl : decls) {
     while (auto overrides = decl->getOverriddenDecl()) {
@@ -95,7 +94,7 @@ bool swift::removeOverriddenDecls(SmallVectorImpl<ValueDecl*> &decls) {
       // C.init overrides B.init overrides A.init, but only C.init and
       // A.init are in the chain. Make sure we still remove A.init from the
       // set in this case.
-      if (decl->getFullName().getBaseName() == ctx.Id_init) {
+      if (decl->getFullName().getBaseName() == DeclBaseName::createConstructor()) {
         /// FIXME: Avoid the possibility of an infinite loop by fixing the root
         ///        cause instead (incomplete circularity detection).
         assert(decl != overrides && "Circular class inheritance?");
@@ -1367,7 +1366,7 @@ TinyPtrVector<ValueDecl *> NominalTypeDecl::lookupDirect(
   // that appears to special-case initializers (clang-imported initializer
   // sorting, implicit initializer synthesis), so for the time being we have to
   // turn it off for them entirely.
-  if (name.getBaseName() == ctx.Id_init)
+  if (name.getBaseName() == DeclBaseName::createConstructor())
     useNamedLazyMemberLoading = false;
 
   DEBUG(llvm::dbgs() << getNameStr() << ".lookupDirect(" << name << ")"
@@ -1753,7 +1752,7 @@ bool DeclContext::lookupQualified(Type type,
 
     // Make sure we've resolved implicit members, if we need them.
     if (typeResolver) {
-      if (member.getBaseName() == ctx.Id_init)
+      if (member.getBaseName() == DeclBaseName::createConstructor())
         typeResolver->resolveImplicitConstructors(current);
 
       typeResolver->resolveImplicitMember(current, member);
@@ -1782,7 +1781,7 @@ bool DeclContext::lookupQualified(Type type,
       // current class permits inheritance. Even then, only find complete
       // object initializers.
       bool visitSuperclass = true;
-      if (member.getBaseName() == ctx.Id_init) {
+      if (member.getBaseName() == DeclBaseName::createConstructor()) {
         if (classDecl->inheritsSuperclassInitializers(typeResolver))
           onlyCompleteObjectInits = true;
         else

lib/ClangImporter/IAMInference.cpp

@@ -212,7 +212,8 @@ class IAMInference {
   IAMResult importAsTypeID(const clang::QualType typeIDTy,
                            EffectiveClangContext effectiveDC) {
     ++SuccessImportAsTypeID;
-    return {formDeclName("typeID"), IAMAccessorKind::Getter, effectiveDC};
+    return {formDeclName("typeID", /*isInitializer=*/false),
+            IAMAccessorKind::Getter, effectiveDC};
   }
 
   // Init
@@ -245,7 +246,7 @@ class IAMInference {
 
       assert(didDrop != 0 && "specifier not present?");
     }
-    return {formDeclName("init", params, prefix), effectiveDC};
+    return {formDeclName("init", true, params, prefix), effectiveDC};
   }
 
   // Instance computed property
@@ -259,7 +260,8 @@ class IAMInference {
         propSpec == "Get" ? IAMAccessorKind::Getter : IAMAccessorKind::Setter;
     assert(kind == IAMAccessorKind::Getter || pairedAccessor && "no set-only");
 
-    return {formDeclName(name), kind, selfIdx, effectiveDC};
+    return {formDeclName(name, /*isInitializer=*/false),
+            kind, selfIdx, effectiveDC};
   }
 
   // Instance method
@@ -268,14 +270,15 @@ class IAMInference {
                          ArrayRef<const clang::ParmVarDecl *> nonSelfParams,
                          EffectiveClangContext effectiveDC) {
     ++SuccessImportAsInstanceMethod;
-    return {formDeclName(name, nonSelfParams), selfIdx, effectiveDC};
+    return {formDeclName(name, /*isInitializer=*/false, nonSelfParams),
+            selfIdx, effectiveDC};
   }
 
   // Static stored property
   IAMResult importAsStaticProperty(StringRef name,
                                    EffectiveClangContext effectiveDC) {
     ++SuccessImportAsStaticProperty;
-    return {formDeclName(name), effectiveDC};
+    return {formDeclName(name, /*isInitializer=*/false), effectiveDC};
   }
 
   // Static computed property
@@ -289,7 +292,8 @@ class IAMInference {
         propSpec == "Get" ? IAMAccessorKind::Getter : IAMAccessorKind::Setter;
     assert(kind == IAMAccessorKind::Getter || pairedAccessor && "no set-only");
 
-    return {formDeclName(name), kind, effectiveDC};
+    return {formDeclName(name, /*isInitializer=*/false),
+            kind, effectiveDC};
   }
 
   // Static method
@@ -298,7 +302,8 @@ class IAMInference {
                        ArrayRef<const clang::ParmVarDecl *> nonSelfParams,
                        EffectiveClangContext effectiveDC) {
     ++SuccessImportAsStaticMethod;
-    return {formDeclName(name, nonSelfParams), effectiveDC};
+    return {formDeclName(name, /*isInitializer=*/false, nonSelfParams),
+            effectiveDC};
   }
 
   Identifier getIdentifier(StringRef str) {
@@ -379,18 +384,20 @@ class IAMInference {
     return clangLookupFunction(pairName);
   }
 
-  Identifier getHumbleIdentifier(StringRef name) {
+  DeclBaseName getHumbleBaseName(StringRef name, bool isInitializer) {
     // Lower-camel-case the incoming name
     NameBuffer buf;
     formHumbleCamelName(name, buf);
+    if (isInitializer && buf == "init")
+      return DeclBaseName::createConstructor();
     return getIdentifier(buf);
   }
 
-  DeclName formDeclName(StringRef baseName) {
-    return {getHumbleIdentifier(baseName)};
+  DeclName formDeclName(StringRef baseName, bool isInitializer) {
+    return {getHumbleBaseName(baseName, isInitializer)};
   }
 
-  DeclName formDeclName(StringRef baseName,
+  DeclName formDeclName(StringRef baseName, bool isInitializer,
                         ArrayRef<const clang::ParmVarDecl *> params,
                         StringRef firstPrefix = "") {
 
@@ -402,7 +409,7 @@ class IAMInference {
       // We need to form an argument label, despite there being no argument
       NameBuffer paramName;
       formHumbleCamelName(firstPrefix, paramName);
-      return {context, getHumbleIdentifier(baseName),
+      return {context, getHumbleBaseName(baseName, isInitializer),
               getIdentifier(paramName)};
     }
 
@@ -426,7 +433,9 @@ class IAMInference {
       SmallVector<Identifier, 8> argLabels;
       for (auto str : argStrs)
         argLabels.push_back(getIdentifier(str));
-      DEBUG((beforeOmit = {context, getHumbleIdentifier(baseName), argLabels}));
+      DEBUG((beforeOmit = {context,
+                           getHumbleBaseName(baseName, isInitializer),
+                           argLabels}));
     }
 
     SmallVector<OmissionTypeName, 8> paramTypeNames;
@@ -435,16 +444,18 @@ class IAMInference {
           clangSema.getASTContext(), param->getType()));
     }
 
-    auto humbleBaseName = getHumbleIdentifier(baseName);
-    baseName = humbleBaseName.str();
+    auto humbleBaseName = getHumbleBaseName(baseName, isInitializer);
+    baseName = humbleBaseName.userFacingName();
     bool didOmit =
         omitNeedlessWords(baseName, argStrs, "", "", "", paramTypeNames, false,
                           false, nullptr, scratch);
     SmallVector<Identifier, 8> argLabels;
     for (auto str : argStrs)
       argLabels.push_back(getIdentifier(str));
 
-    DeclName ret = {context, getHumbleIdentifier(baseName), argLabels};
+    DeclName ret(context,
+                 getHumbleBaseName(baseName, isInitializer),
+                 argLabels);
 
     if (didOmit) {
       ++OmitNumTimes;

lib/ClangImporter/ImportDecl.cpp

@@ -444,7 +444,7 @@ makeEnumRawValueConstructor(ClangImporter::Implementation &Impl,
 
   auto paramPL = ParameterList::createWithoutLoc(param);
 
-  DeclName name(C, C.Id_init, paramPL);
+  DeclName name(C, DeclBaseName::createConstructor(), paramPL);
   auto *ctorDecl =
     new (C) ConstructorDecl(name, enumDecl->getLoc(),
                             OTK_Optional, /*FailabilityLoc=*/SourceLoc(),
@@ -1167,7 +1167,7 @@ createDefaultConstructor(ClangImporter::Implementation &Impl,
   auto emptyPL = ParameterList::createEmpty(context);
 
   // Create the constructor.
-  DeclName name(context, context.Id_init, emptyPL);
+  DeclName name(context, DeclBaseName::createConstructor(), emptyPL);
   auto constructor = new (context) ConstructorDecl(
       name, structDecl->getLoc(), OTK_None, /*FailabilityLoc=*/SourceLoc(),
       /*Throws=*/false, /*ThrowsLoc=*/SourceLoc(), selfDecl, emptyPL,
@@ -1282,7 +1282,7 @@ createValueConstructor(ClangImporter::Implementation &Impl,
       ParameterList::create(context, valueParameters)};
 
   // Create the constructor
-  DeclName name(context, context.Id_init, paramLists[1]);
+  DeclName name(context, DeclBaseName::createConstructor(), paramLists[1]);
   auto constructor = new (context) ConstructorDecl(
       name, structDecl->getLoc(), OTK_None, /*FailabilityLoc=*/SourceLoc(),
       /*Throws=*/false, /*ThrowsLoc=*/SourceLoc(), selfDecl, paramLists[1],
@@ -2264,7 +2264,7 @@ namespace {
 
     bool isFactoryInit(ImportedName &name) {
       return name &&
-             name.getDeclName().getBaseName() == Impl.SwiftContext.Id_init &&
+             name.getDeclName().getBaseName() == DeclBaseName::createConstructor() &&
              (name.getInitKind() == CtorInitializerKind::Factory ||
               name.getInitKind() == CtorInitializerKind::ConvenienceFactory);
     }
@@ -3521,7 +3521,7 @@ namespace {
       DeclName name = accessorInfo ? DeclName() : importedName.getDeclName();
       if (importedName.importAsMember()) {
         // Handle initializers.
-        if (name.getBaseName() == Impl.SwiftContext.Id_init) {
+        if (name.getBaseName() == DeclBaseName::createConstructor()) {
           assert(!accessorInfo);
           return importGlobalAsInitializer(decl, name, dc,
                                            importedName.getInitKind(),
@@ -7234,7 +7234,7 @@ void SwiftDeclConverter::importInheritedConstructors(
   // If we have a superclass, import from it.
   if (auto superclassClangDecl = superclass->getClangDecl()) {
     if (isa<clang::ObjCInterfaceDecl>(superclassClangDecl)) {
-      inheritConstructors(superclass->lookupDirect(Impl.SwiftContext.Id_init),
+      inheritConstructors(superclass->lookupDirect(DeclBaseName::createConstructor()),
                           kind);
     }
   }

lib/ClangImporter/ImportName.cpp

@@ -1712,7 +1712,8 @@ ImportedName NameImporter::importNameImpl(const clang::NamedDecl *D,
     }
   }
 
-  result.declName = formDeclName(swiftCtx, baseName, argumentNames, isFunction);
+  result.declName = formDeclName(swiftCtx, baseName, argumentNames, isFunction,
+                                 isInitializer);
   return result;
 }