Merge pull request swiftlang#63228 from DougGregor/freestanding-macro-attr-cleanup

Author: DougGregor

include/swift/AST/Attr.h

@@ -2307,69 +2307,38 @@ class ObjCImplementationAttr final : public DeclAttribute {
   }
 };
 
-class DeclarationAttr final
+/// A macro role attribute, spelled with either @attached or @freestanding,
+/// which declares one of the roles that a given macro can inhabit.
+class MacroRoleAttr final
     : public DeclAttribute,
-      private llvm::TrailingObjects<DeclarationAttr, MacroIntroducedDeclName> {
-  friend TrailingObjects;
-
-  MacroRole role;
-  unsigned numPeerNames, numMemberNames;
-
-  DeclarationAttr(SourceLoc atLoc, SourceRange range, MacroRole role,
-                  ArrayRef<MacroIntroducedDeclName> peerNames,
-                  ArrayRef<MacroIntroducedDeclName> memberNames,
-                  bool implicit);
-
-public:
-  static DeclarationAttr *create(ASTContext &ctx, SourceLoc atLoc,
-                                 SourceRange range, MacroRole role,
-                                 ArrayRef<MacroIntroducedDeclName> peerNames,
-                                 ArrayRef<MacroIntroducedDeclName> memberNames,
-                                 bool implicit);
-
-  size_t numTrailingObjects(OverloadToken<MacroIntroducedDeclName>) const {
-    return numPeerNames + numMemberNames;
-  }
-
-  MacroRole getMacroRole() const { return role; }
-  ArrayRef<MacroIntroducedDeclName> getPeerAndMemberNames() const;
-  ArrayRef<MacroIntroducedDeclName> getPeerNames() const;
-  ArrayRef<MacroIntroducedDeclName> getMemberNames() const;
-
-  static bool classof(const DeclAttribute *DA) {
-    return DA->getKind() == DAK_Declaration;
-  }
-};
-
-/// The @attached attribute, which declares that a given macro can be
-/// "attached" as an attribute to declarations.
-class AttachedAttr final
-    : public DeclAttribute,
-      private llvm::TrailingObjects<AttachedAttr, MacroIntroducedDeclName> {
+      private llvm::TrailingObjects<MacroRoleAttr, MacroIntroducedDeclName> {
   friend TrailingObjects;
 
+  MacroSyntax syntax;
   MacroRole role;
   unsigned numNames;
 
-  AttachedAttr(SourceLoc atLoc, SourceRange range, MacroRole role,
-               ArrayRef<MacroIntroducedDeclName> names,
-               bool implicit);
+  MacroRoleAttr(SourceLoc atLoc, SourceRange range, MacroSyntax syntax,
+                MacroRole role, ArrayRef<MacroIntroducedDeclName> names,
+                bool implicit);
 
 public:
-  static AttachedAttr *create(ASTContext &ctx, SourceLoc atLoc,
-                              SourceRange range, MacroRole role,
-                              ArrayRef<MacroIntroducedDeclName> names,
-                              bool implicit);
+  static MacroRoleAttr *create(ASTContext &ctx, SourceLoc atLoc,
+                               SourceRange range, MacroSyntax syntax,
+                               MacroRole role,
+                               ArrayRef<MacroIntroducedDeclName> names,
+                               bool implicit);
 
   size_t numTrailingObjects(OverloadToken<MacroIntroducedDeclName>) const {
     return numNames;
   }
 
+  MacroSyntax getMacroSyntax() const { return syntax; }
   MacroRole getMacroRole() const { return role; }
   ArrayRef<MacroIntroducedDeclName> getNames() const;
 
   static bool classof(const DeclAttribute *DA) {
-    return DA->getKind() == DAK_Attached;
+    return DA->getKind() == DAK_MacroRole;
   }
 };
 

include/swift/AST/DiagnosticsParse.def

@@ -2043,6 +2043,8 @@ ERROR(macro_attribute_introduced_name_requires_argument,PointsToFirstBadToken,
       "introduced name kind %0 requires a single argument '(name)'", (Identifier))
 ERROR(macro_attribute_introduced_name_requires_no_argument,PointsToFirstBadToken,
       "introduced name kind %0 must not have an argument", (Identifier))
+WARNING(macro_expression_attribute_removed,PointsToFirstBadToken,
+      "@expression has been removed in favor of @freestanding(expression)", ())
 
 ERROR(unexpected_attribute_expansion,PointsToFirstBadToken,
       "unexpected token '%0' in expanded attribute list'",

include/swift/AST/DiagnosticsSema.def

@@ -6860,8 +6860,8 @@ WARNING(macro_type_access_warn,none,
         (bool, AccessLevel, AccessLevel, bool))
 ERROR(macro_in_nested,none,
       "macro %0 can only be declared at file scope", (DeclName))
-ERROR(macro_without_context,none,
-      "macro %0 must declare its applicable contexts (e.g., '@expression')",
+ERROR(macro_without_role,none,
+      "macro %0 must declare its applicable roles via '@freestanding' or @attached'",
        (DeclName))
 ERROR(macro_expansion_missing_pound,none,
       "expansion of macro %0 requires leading '#'", (DeclName))

include/swift/AST/MacroDeclaration.h

@@ -21,14 +21,25 @@
 
 namespace swift {
 
+/// Describes the syntax that is used for a macro, which affects its role.
+enum class MacroSyntax: uint8_t {
+  /// Freestanding macro syntax starting with an explicit '#' followed by the
+  /// macro name and optional arguments.
+  Freestanding,
+
+  /// Attached macro syntax written as an attribute with a leading `@` followed
+  /// by the macro name an optional arguments.
+  Attached,
+};
+
 /// The context in which a macro can be used, which determines the syntax it
 /// uses.
 enum class MacroRole: uint32_t {
   /// An expression macro, referenced explicitly via "#stringify" or similar
   /// in the source code.
   Expression = 0x01,
   /// A freestanding declaration macro.
-  FreestandingDeclaration = 0x02,
+  Declaration = 0x02,
   /// An attached macro that declares accessors for a variable or subscript
   /// declaration.
   Accessor = 0x04,

include/swift/AST/TypeCheckRequests.h

@@ -3783,23 +3783,6 @@ class GetTypeWrapperInitializer
   bool isCached() const { return true; }
 };
 
-/// Check whether this is a protocol that has a type wrapper attribute
-/// or one of its dependencies does.
-class UsesTypeWrapperFeature
-    : public SimpleRequest<UsesTypeWrapperFeature, bool(NominalTypeDecl *),
-                           RequestFlags::Cached> {
-public:
-  using SimpleRequest::SimpleRequest;
-
-private:
-  friend SimpleRequest;
-
-  bool evaluate(Evaluator &evaluator, NominalTypeDecl *) const;
-
-public:
-  bool isCached() const { return true; }
-};
-
 /// Find the definition of a given macro.
 class MacroDefinitionRequest
     : public SimpleRequest<MacroDefinitionRequest,

include/swift/Parse/Parser.h

@@ -1101,13 +1101,11 @@ class Parser {
   bool parseDocumentationAttributeArgument(Optional<StringRef> &Metadata,
                                            Optional<AccessLevel> &Visibility);
 
-  /// Parse the @declaration attribute.
-  ParserResult<DeclarationAttr> parseDeclarationAttribute(SourceLoc AtLoc,
-                                                          SourceLoc Loc);
-
-  /// Parse the @attached attribute.
-  ParserResult<AttachedAttr> parseAttachedAttribute(SourceLoc AtLoc,
-                                                    SourceLoc Loc);
+  /// Parse the @attached or @freestanding attribute that specifies a macro
+  /// role.
+  ParserResult<MacroRoleAttr> parseMacroRoleAttribute(
+      MacroSyntax syntax, SourceLoc AtLoc, SourceLoc Loc
+  );
 
   /// Parse a specific attribute.
   ParserStatus parseDeclAttribute(DeclAttributes &Attributes, SourceLoc AtLoc,

lib/AST/ASTScopeCreation.cpp

@@ -255,7 +255,7 @@ ASTSourceFileScope::ASTSourceFileScope(SourceFile *SF,
     // Determine the parent source location based on the macro role.
     switch (*macroRole) {
     case MacroRole::Expression:
-    case MacroRole::FreestandingDeclaration:
+    case MacroRole::Declaration:
     case MacroRole::Accessor:
     case MacroRole::MemberAttribute:
       parentLoc = expansion.getStartLoc();

lib/AST/Attr.cpp

@@ -1311,19 +1311,18 @@ bool DeclAttribute::printImpl(ASTPrinter &Printer, const PrintOptions &Options,
     break;
   }
 
-  case DAK_Declaration: {
-    Printer.printAttrName("@declaration");
-    Printer << "(";
-    auto Attr = cast<DeclarationAttr>(this);
-    Printer << getMacroRoleString(Attr->getMacroRole());
-    Printer << ")";
-    break;
-  }
+  case DAK_MacroRole: {
+    auto Attr = cast<MacroRoleAttr>(this);
+    switch (Attr->getMacroSyntax()) {
+    case MacroSyntax::Freestanding:
+      Printer.printAttrName("@freestanding");
+      break;
 
-  case DAK_Attached: {
-    Printer.printAttrName("@attached");
+    case MacroSyntax::Attached:
+      Printer.printAttrName("@attached");
+      break;
+    }
     Printer << "(";
-    auto Attr = cast<AttachedAttr>(this);
     Printer << getMacroRoleString(Attr->getMacroRole());
     if (!Attr->getNames().empty()) {
       Printer << ", names: ";
@@ -1518,10 +1517,14 @@ StringRef DeclAttribute::getAttrName() const {
     return "_expose";
   case DAK_Documentation:
     return "_documentation";
-  case DAK_Declaration:
-    return "declaration";
-  case DAK_Attached:
-    return "attached";
+  case DAK_MacroRole:
+    switch (cast<MacroRoleAttr>(this)->getMacroSyntax()) {
+    case MacroSyntax::Freestanding:
+      return "freestanding";
+
+    case MacroSyntax::Attached:
+      return "attached";
+    }
   }
   llvm_unreachable("bad DeclAttrKind");
 }
@@ -2359,73 +2362,27 @@ bool CustomAttr::isAttachedMacro(const Decl *decl) const {
   return macroDecl != nullptr;
 }
 
-DeclarationAttr::DeclarationAttr(SourceLoc atLoc, SourceRange range,
-                                 MacroRole role,
-                                 ArrayRef<MacroIntroducedDeclName> peerNames,
-                                 ArrayRef<MacroIntroducedDeclName> memberNames,
-                                 bool implicit)
-    : DeclAttribute(DAK_Declaration, atLoc, range, implicit),
-      role(role), numPeerNames(peerNames.size()),
-      numMemberNames(memberNames.size()) {
-  auto *trailingNamesBuffer = getTrailingObjects<MacroIntroducedDeclName>();
-  std::uninitialized_copy(peerNames.begin(), peerNames.end(),
-                          trailingNamesBuffer);
-  std::uninitialized_copy(memberNames.begin(), memberNames.end(),
-                          trailingNamesBuffer + peerNames.size());
-}
-
-DeclarationAttr *
-DeclarationAttr::create(ASTContext &ctx, SourceLoc atLoc, SourceRange range,
-                        MacroRole role,
-                        ArrayRef<MacroIntroducedDeclName> peerNames,
-                        ArrayRef<MacroIntroducedDeclName> memberNames,
-                        bool implicit) {
-  unsigned size = totalSizeToAlloc<MacroIntroducedDeclName>(
-      peerNames.size() + memberNames.size());
-  auto *mem = ctx.Allocate(size, alignof(DeclarationAttr));
-  return new (mem) DeclarationAttr(atLoc, range, role, peerNames,
-                                   memberNames, implicit);
-}
-
-ArrayRef<MacroIntroducedDeclName> DeclarationAttr::getPeerAndMemberNames() const {
-  return {
-    getTrailingObjects<MacroIntroducedDeclName>(),
-    numPeerNames + numMemberNames
-  };
-}
-
-ArrayRef<MacroIntroducedDeclName> DeclarationAttr::getPeerNames() const {
-  return {getTrailingObjects<MacroIntroducedDeclName>(), numPeerNames};
-}
-
-ArrayRef<MacroIntroducedDeclName> DeclarationAttr::getMemberNames() const {
-  return {
-    getTrailingObjects<MacroIntroducedDeclName>() + numPeerNames,
-    numMemberNames
-  };
-}
-
-AttachedAttr::AttachedAttr(SourceLoc atLoc, SourceRange range,
-                           MacroRole role,
-                           ArrayRef<MacroIntroducedDeclName> names,
-                           bool implicit)
-    : DeclAttribute(DAK_Attached, atLoc, range, implicit),
-      role(role), numNames(names.size()) {
+MacroRoleAttr::MacroRoleAttr(SourceLoc atLoc, SourceRange range,
+                             MacroSyntax syntax, MacroRole role,
+                             ArrayRef<MacroIntroducedDeclName> names,
+                             bool implicit)
+    : DeclAttribute(DAK_MacroRole, atLoc, range, implicit),
+      syntax(syntax), role(role), numNames(names.size()) {
   auto *trailingNamesBuffer = getTrailingObjects<MacroIntroducedDeclName>();
   std::uninitialized_copy(names.begin(), names.end(), trailingNamesBuffer);
 }
 
-AttachedAttr *
-AttachedAttr::create(ASTContext &ctx, SourceLoc atLoc, SourceRange range,
-                     MacroRole role,
-                     ArrayRef<MacroIntroducedDeclName> names,
-                     bool implicit) {
+MacroRoleAttr *
+MacroRoleAttr::create(ASTContext &ctx, SourceLoc atLoc, SourceRange range,
+                      MacroSyntax syntax, MacroRole role,
+                      ArrayRef<MacroIntroducedDeclName> names,
+                      bool implicit) {
   unsigned size = totalSizeToAlloc<MacroIntroducedDeclName>(names.size());
-  auto *mem = ctx.Allocate(size, alignof(AttachedAttr));
-  return new (mem) AttachedAttr(atLoc, range, role, names, implicit);
+  auto *mem = ctx.Allocate(size, alignof(MacroRoleAttr));
+  return new (mem) MacroRoleAttr(atLoc, range, syntax, role, names, implicit);
 }
 
-ArrayRef<MacroIntroducedDeclName> AttachedAttr::getNames() const {
+ArrayRef<MacroIntroducedDeclName> MacroRoleAttr::getNames() const {
   return {
     getTrailingObjects<MacroIntroducedDeclName>(),
     numNames

lib/AST/Decl.cpp

@@ -9717,7 +9717,7 @@ StringRef swift::getMacroRoleString(MacroRole role) {
   case MacroRole::Expression:
     return "expression";
 
-  case MacroRole::FreestandingDeclaration:
+  case MacroRole::Declaration:
     return "freestanding";
 
   case MacroRole::Accessor:
@@ -9769,7 +9769,7 @@ StringRef swift::getMacroIntroducedDeclNameString(
 static MacroRoles freestandingMacroRoles =
   (MacroRoles() |
    MacroRole::Expression |
-   MacroRole::FreestandingDeclaration);
+   MacroRole::Declaration);
 static MacroRoles attachedMacroRoles = (MacroRoles() |
                                         MacroRole::Accessor |
                                         MacroRole::MemberAttribute |
@@ -9825,11 +9825,7 @@ SourceRange MacroDecl::getSourceRange() const {
 
 MacroRoles MacroDecl::getMacroRoles() const {
   MacroRoles contexts = None;
-  if (getAttrs().hasAttribute<ExpressionAttr>())
-    contexts |= MacroRole::Expression;
-  for (auto attr : getAttrs().getAttributes<DeclarationAttr>())
-    contexts |= attr->getMacroRole();
-  for (auto attr : getAttrs().getAttributes<AttachedAttr>())
+  for (auto attr : getAttrs().getAttributes<MacroRoleAttr>())
     contexts |= attr->getMacroRole();
   return contexts;
 }

lib/AST/Module.cpp

@@ -907,7 +907,7 @@ Optional<MacroRole> SourceFile::getFulfilledMacroRole() const {
     return MacroRole::Expression;
 
   case GeneratedSourceInfo::FreestandingDeclMacroExpansion:
-    return MacroRole::FreestandingDeclaration;
+    return MacroRole::Declaration;
 
   case GeneratedSourceInfo::AccessorMacroExpansion:
     return MacroRole::Accessor;