Merge pull request #77580 from DougGregor/swift-attr-parsing-fixes

Ensure that buffers containing Clang swift_attr attributes are parsed as attributes

Author: DougGregor

include/swift/AST/ASTScope.h

@@ -808,6 +808,8 @@ class AbstractFunctionDeclScope final : public ASTScopeImpl {
 protected:
   void printSpecifics(llvm::raw_ostream &out) const override;
 
+  bool lookupLocalsOrMembers(DeclConsumer) const override;
+
 public:
   Decl *getDecl() const { return decl; }
 

include/swift/AST/NameLookup.h

@@ -528,6 +528,15 @@ void lookupVisibleMemberDecls(VisibleDeclConsumer &Consumer,
                               bool includeProtocolExtensionMembers,
                               GenericSignature genericSig = GenericSignature());
 
+/// Determine the module-scope context from which lookup should proceed.
+///
+/// In the common case, module-scope context is the source file in which
+/// the declaration context is nested. However, when declaration context is
+/// part of an imported Clang declaration context, it won't be nested within a
+/// source file. Rather, the source file will be on the side, and will be
+/// provided here because it contains information about the available imports.
+DeclContext *getModuleScopeLookupContext(DeclContext *dc);
+
 namespace namelookup {
 
 /// Add semantic members to \p type before attempting a semantic lookup.

include/swift/Basic/BasicBridging.h

@@ -445,6 +445,7 @@ enum ENUM_EXTENSIBILITY_ATTR(closed) BridgedGeneratedSourceFileKind {
   BridgedGeneratedSourceFileKindReplacedFunctionBody,
   BridgedGeneratedSourceFileKindPrettyPrinted,
   BridgedGeneratedSourceFileKindDefaultArgument,
+  BridgedGeneratedSourceFileKindAttribute,
 
   BridgedGeneratedSourceFileKindNone,
 };

include/swift/Basic/SourceManager.h

@@ -65,6 +65,9 @@ class GeneratedSourceInfo {
 
     /// The expansion of default argument at caller side
     DefaultArgument,
+
+    /// A Swift attribute expressed in C headers.
+    Attribute,
   } kind;
 
   static StringRef kindToString(GeneratedSourceInfo::Kind kind) {
@@ -80,6 +83,8 @@ class GeneratedSourceInfo {
       return "PrettyPrinted";
     case DefaultArgument:
       return "DefaultArgument";
+    case Attribute:
+      return "Attribute";
     }
     llvm_unreachable("Invalid kind");
   }

include/swift/Subsystems.h

@@ -120,6 +120,12 @@ namespace swift {
   /// This walks the AST to resolve imports.
   void performImportResolution(SourceFile &SF);
 
+  /// Resolve imports for a source file generated to adapt a given
+  /// Clang module.
+  void performImportResolutionForClangMacroBuffer(
+    SourceFile &SF, ModuleDecl *clangModule
+  );
+
   /// Once type-checking is complete, this instruments code with calls to an
   /// intrinsic that record the expected values of local variables so they can
   /// be compared against the results from the debugger.

lib/AST/ASTMangler.cpp

@@ -4535,6 +4535,7 @@ void ASTMangler::appendMacroExpansionContext(
   case GeneratedSourceInfo::PrettyPrinted:
   case GeneratedSourceInfo::ReplacedFunctionBody:
   case GeneratedSourceInfo::DefaultArgument:
+  case GeneratedSourceInfo::Attribute:
     return appendMacroExpansionLoc();
   }
 
@@ -4586,6 +4587,7 @@ void ASTMangler::appendMacroExpansionContext(
   case GeneratedSourceInfo::PrettyPrinted:
   case GeneratedSourceInfo::ReplacedFunctionBody:
   case GeneratedSourceInfo::DefaultArgument:
+  case GeneratedSourceInfo::Attribute:
     llvm_unreachable("Exited above");
   }
 

lib/AST/ASTScopeLookup.cpp

@@ -30,6 +30,7 @@
 #include "swift/AST/Stmt.h"
 #include "swift/AST/TypeRepr.h"
 #include "swift/Basic/STLExtras.h"
+#include "swift/ClangImporter/ClangModule.h"
 #include "swift/Parse/Lexer.h"
 #include "llvm/Support/Compiler.h"
 
@@ -264,6 +265,20 @@ bool ASTScopeImpl::lookupLocalsOrMembers(DeclConsumer) const {
   return false; // many kinds of scopes have none
 }
 
+bool AbstractFunctionDeclScope::lookupLocalsOrMembers(DeclConsumer consumer) const {
+  // Special case: if we're within a function inside a type context, but the
+  // parent context is within a Clang module unit, we need to make sure to
+  // look for members in it.
+  auto dc = decl->getDeclContext();
+  if (!dc->isTypeContext())
+    return false;
+
+  if (!isa<ClangModuleUnit>(dc->getModuleScopeContext()))
+    return false;
+
+  return consumer.lookInMembers(cast<GenericContext>(dc->getAsDecl()));
+}
+
 bool GenericTypeOrExtensionScope::lookupLocalsOrMembers(
     ASTScopeImpl::DeclConsumer consumer) const {
   return portion->lookupMembersOf(this, consumer);

lib/AST/AvailabilityScope.cpp

@@ -55,8 +55,10 @@ AvailabilityScope::createForSourceFile(SourceFile *SF,
   case SourceFileKind::DefaultArgument: {
     // Look up the parent context in the enclosing file that this file's
     // root context should be nested under.
-    if (auto parentScope =
-            SF->getEnclosingSourceFile()->getAvailabilityScope()) {
+    auto enclosingSF = SF->getEnclosingSourceFile();
+    if (!enclosingSF)
+      break;
+    if (auto parentScope = enclosingSF->getAvailabilityScope()) {
       auto charRange = Ctx.SourceMgr.getRangeForBuffer(SF->getBufferID());
       range = SourceRange(charRange.getStart(), charRange.getEnd());
       auto originalNode = SF->getNodeInEnclosingSourceFile();

lib/AST/Decl.cpp

@@ -12075,6 +12075,7 @@ MacroDiscriminatorContext MacroDiscriminatorContext::getParentOf(
   case GeneratedSourceInfo::PrettyPrinted:
   case GeneratedSourceInfo::ReplacedFunctionBody:
   case GeneratedSourceInfo::DefaultArgument:
+  case GeneratedSourceInfo::Attribute:
     return origDC;
   }
 }

lib/AST/DiagnosticEngine.cpp

@@ -1336,6 +1336,7 @@ DiagnosticEngine::diagnosticInfoForDiagnostic(const Diagnostic &diagnostic) {
 #include "swift/Basic/MacroRoles.def"
       case GeneratedSourceInfo::PrettyPrinted:
       case GeneratedSourceInfo::DefaultArgument:
+      case GeneratedSourceInfo::Attribute:
         fixIts = {};
         break;
       case GeneratedSourceInfo::ReplacedFunctionBody:
@@ -1381,6 +1382,7 @@ getGeneratedSourceInfoMacroName(const GeneratedSourceInfo &info) {
   case GeneratedSourceInfo::PrettyPrinted:
   case GeneratedSourceInfo::ReplacedFunctionBody:
   case GeneratedSourceInfo::DefaultArgument:
+  case GeneratedSourceInfo::Attribute:
     return DeclName();
   }
 }
@@ -1442,6 +1444,7 @@ DiagnosticEngine::getGeneratedSourceBufferNotes(SourceLoc loc) {
 
     case GeneratedSourceInfo::DefaultArgument:
     case GeneratedSourceInfo::ReplacedFunctionBody:
+    case GeneratedSourceInfo::Attribute:
       return childNotes;
     }