[AST] Introduce the ASTPrinter class, and have its callbacks invoked during AST printing.

This provides useful extension points during AST printing.

Swift SVN r11338

include/swift/AST/ASTPrinter.h

@@ -0,0 +1,74 @@
+//===--- ASTPrinter.h - Class for printing the AST --------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_AST_ASTPRINTER_H
+#define SWIFT_AST_ASTPRINTER_H
+
+#include "swift/Basic/LLVM.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace swift {
+  class Decl;
+  class Module;
+  class TypeDecl;
+
+/// An abstract class used to print an AST.
+class ASTPrinter {
+public:
+  virtual ~ASTPrinter() {}
+
+  virtual void printText(StringRef Text) = 0;
+
+  /// Called before printing of a declaration.
+  virtual void printDeclPre(const Decl *D) {}
+  /// Called before printing at the point which would be considered the location
+  /// of the declaration (normally the name of the declaration).
+  virtual void printDeclLoc(const Decl *D) {}
+  /// Called after finishing printing of a declaration.
+  virtual void printDeclPost(const Decl *D) {}
+
+  /// Called when printing the referenced name of a type declaration.
+  virtual void printTypeRef(const TypeDecl *TD, StringRef Text) {
+    printText(Text);
+  }
+  /// Called when printing the referenced name of a module.
+  virtual void printModuleRef(const Module *Mod, StringRef Text) {
+    printText(Text);
+  }
+
+  // Helper functions.
+
+  ASTPrinter &operator<<(StringRef Text) {
+    printText(Text);
+    return *this;
+  }
+  ASTPrinter &operator<<(unsigned long long N);
+  void indent(unsigned NumSpaces);
+
+private:
+  virtual void anchor();
+};
+
+/// An AST printer for a raw_ostream.
+class StreamPrinter : public ASTPrinter {
+protected:
+  raw_ostream &OS;
+
+public:
+  explicit StreamPrinter(raw_ostream &OS) : OS(OS) {}
+
+  void printText(StringRef Text) override;
+};
+
+} // namespace swift
+
+#endif // LLVM_SWIFT_AST_ASTPRINTER_H

include/swift/AST/Decl.h

@@ -43,6 +43,7 @@ namespace clang {
 namespace swift {
   class ArchetypeType;
   class ASTContext;
+  class ASTPrinter;
   class ASTWalker;
   class Type;
   class Expr;
@@ -377,18 +378,14 @@ public:
   ///
   /// \param OS Output stream to which the declaration will be printed.
   void print(raw_ostream &OS) const;
+  void print(raw_ostream &OS, const PrintOptions &Opts) const;
 
   /// \brief Pretty-print the given declaration.
   ///
-  /// \param os Output stream to which the declaration will be printed.
+  /// \param Printer ASTPrinter object.
   ///
-  /// \param options Options to control how pretty-printing is performed.
-  ///
-  /// \param declOffsets If non-null, will be populated with the stream offsets
-  /// at which each declaration encountered is printed.
-  void print(raw_ostream &os, const PrintOptions &options,
-             SmallVectorImpl<std::pair<Decl *, uint64_t>> *declOffsets
-               = nullptr) const;
+  /// \param Opts Options to control how pretty-printing is performed.
+  void print(ASTPrinter &Printer, const PrintOptions &Opts) const;
 
   /// \brief Determine whether this declaration should be printed when
   /// encountered in its declaration context's list of members.

include/swift/AST/DiagnosticEngine.h

@@ -325,7 +325,7 @@ namespace swift {
 
     /// \brief The set of declarations for which we have pretty-printed
     /// results that we can point to on the command line.
-    llvm::DenseMap<Decl *, SourceLoc> PrettyPrintedDeclarations;
+    llvm::DenseMap<const Decl *, SourceLoc> PrettyPrintedDeclarations;
 
     friend class InFlightDiagnostic;
     

include/swift/AST/Expr.h

@@ -201,6 +201,7 @@ public:
       "only for use within the debugger");
   void dump(raw_ostream &OS) const;
   void print(raw_ostream &OS, unsigned Indent = 0) const;
+  void print(ASTPrinter &Printer, const PrintOptions &Opts) const;
 
   // Only allow allocation of Exprs using the allocator in ASTContext
   // or by doing a placement new.

include/swift/AST/Module.h

@@ -639,8 +639,9 @@ public:
 
   /// \brief Pretty-print the contents of this source file.
   ///
-  /// \param OS The stream to which the contents will be printed.
+  /// \param Printer The AST printer used for printing the contents.
   /// \param PO Options controlling the printing process.
+  void print(ASTPrinter &Printer, const PrintOptions &PO);
   void print(raw_ostream &OS, const PrintOptions &PO);
 
   static bool classof(const FileUnit *file) {

include/swift/AST/ModuleInterfacePrinting.h

@@ -16,10 +16,11 @@
 #include "swift/Basic/LLVM.h"
 
 namespace swift {
+class ASTPrinter;
 class Module;
 struct PrintOptions;
 
-void printModuleInterface(Module *M, raw_ostream &OS,
+void printModuleInterface(Module *M, ASTPrinter &Printer,
 	                      const PrintOptions &Options);
 
 } // namespace swift

include/swift/AST/Type.h

@@ -25,6 +25,7 @@
 
 namespace swift {
 
+class ASTPrinter;
 class ArchetypeType;
 class ASTContext;
 class LazyResolver;
@@ -106,6 +107,7 @@ public:
   void dump() const;
 
   void print(raw_ostream &OS, const PrintOptions &PO = PrintOptions()) const;
+  void print(ASTPrinter &Printer, const PrintOptions &PO) const;
 
   /// Return the name of the type as a string, for use in diagnostics only.
   std::string getString(const PrintOptions &PO = PrintOptions()) const;

include/swift/AST/TypeRepr.h

@@ -73,7 +73,8 @@ public:
   void operator delete(void *data) = delete;
   void *operator new(size_t bytes, void *data) = delete;
 
-  void print(llvm::raw_ostream &OS) const;
+  void print(raw_ostream &OS, const PrintOptions &Opts = PrintOptions()) const;
+  void print(ASTPrinter &Printer, const PrintOptions &Opts) const;
   void dump() const;
 };
 
@@ -100,7 +101,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return Range.Start; }
   SourceLoc getEndLocImpl() const { return Range.End; }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -122,6 +123,7 @@ public:
   TypeRepr *getTypeRepr() const { return Ty; }
 
   void printAttrs(llvm::raw_ostream &OS) const;
+  void printAttrs(ASTPrinter &Printer) const;
 
   static bool classof(const TypeRepr *T) {
     return T->getKind() == TypeReprKind::Attributed;
@@ -131,7 +133,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return Attrs.AtLoc; }
   SourceLoc getEndLocImpl() const { return Ty->getEndLoc(); }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -214,7 +216,7 @@ private:
       return Components.back().getGenericArgs().back()->getEndLoc();
     return Components.back().getIdLoc();
   }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -246,7 +248,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return ArgsTy->getStartLoc(); }
   SourceLoc getEndLocImpl() const { return RetTy->getEndLoc(); }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -285,7 +287,7 @@ private:
       return Base->getEndLoc();
     return Brackets.End;
   }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -312,7 +314,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return Base->getStartLoc(); }
   SourceLoc getEndLocImpl() const { return QuestionLoc; }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -353,7 +355,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return Parens.Start; }
   SourceLoc getEndLocImpl() const { return Parens.End; }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -383,7 +385,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return IdLoc; }
   SourceLoc getEndLocImpl() const { return Ty->getEndLoc(); }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -421,7 +423,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return ProtocolLoc; }
   SourceLoc getEndLocImpl() const { return AngleBrackets.End; }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 
@@ -449,7 +451,7 @@ public:
 private:
   SourceLoc getStartLocImpl() const { return Base->getStartLoc(); }
   SourceLoc getEndLocImpl() const { return MetaLoc; }
-  void printImpl(llvm::raw_ostream &OS) const;
+  void printImpl(ASTPrinter &Printer, const PrintOptions &Opts) const;
   friend class TypeRepr;
 };
 

include/swift/AST/Types.h

@@ -379,6 +379,7 @@ public:
   void dump() const;
   void print(raw_ostream &OS,
              const PrintOptions &PO = PrintOptions()) const;
+  void print(ASTPrinter &Printer, const PrintOptions &PO) const;
 
   /// Return the name of the type as a string, for use in diagnostics only.
   std::string getString(const PrintOptions &PO = PrintOptions()) const;
@@ -1770,6 +1771,7 @@ public:
   void dump() const;
   void print(llvm::raw_ostream &out,
              const PrintOptions &options = PrintOptions()) const;
+  void print(ASTPrinter &Printer, const PrintOptions &Options) const;
   friend llvm::raw_ostream &operator<<(llvm::raw_ostream &out,
                                        SILParameterInfo type) {
     type.print(out);
@@ -1849,6 +1851,7 @@ public:
   void dump() const;
   void print(llvm::raw_ostream &out,
              const PrintOptions &options = PrintOptions()) const;
+  void print(ASTPrinter &Printer, const PrintOptions &Options) const;
   friend llvm::raw_ostream &operator<<(llvm::raw_ostream &out,
                                        SILResultInfo type) {
     type.print(out);

lib/AST/ASTDumper.cpp

@@ -15,6 +15,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "swift/AST/AST.h"
+#include "swift/AST/ASTPrinter.h"
 #include "swift/AST/ASTVisitor.h"
 #include "swift/Basic/STLExtras.h"
 #include "llvm/ADT/APFloat.h"
@@ -1446,6 +1447,14 @@ void Expr::print(raw_ostream &OS, unsigned Indent) const {
   PrintExpr(OS, Indent).visit(const_cast<Expr*>(this));
 }
 
+void Expr::print(ASTPrinter &Printer, const PrintOptions &Opts) const {
+  // FIXME: Fully use the ASTPrinter.
+  llvm::SmallString<128> Str;
+  llvm::raw_svector_ostream OS(Str);
+  print(OS);
+  Printer << OS.str();
+}
+
 //===----------------------------------------------------------------------===//
 // Printing for TypeRepr and all subclasses.
 //===----------------------------------------------------------------------===//

lib/AST/DiagnosticEngine.cpp

@@ -15,6 +15,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "swift/AST/ASTPrinter.h"
 #include "swift/AST/Decl.h"
 #include "swift/AST/DiagnosticEngine.h"
 #include "swift/AST/Module.h"
@@ -325,7 +326,20 @@ void DiagnosticEngine::flushActiveDiagnostic() {
       // so we can point to it.
       SourceLoc ppLoc = PrettyPrintedDeclarations[ActiveDiagnosticDecl];
       if (ppLoc.isInvalid()) {
-        SmallVector<std::pair<Decl *, uint64_t>, 8> entries;
+        class TrackingPrinter : public StreamPrinter {
+          SmallVectorImpl<std::pair<const Decl *, uint64_t>> &Entries;
+
+        public:
+          TrackingPrinter(
+              SmallVectorImpl<std::pair<const Decl *, uint64_t>> &Entries,
+              raw_ostream &OS) :
+            StreamPrinter(OS), Entries(Entries) {}
+
+          void printDeclLoc(const Decl *D) override {
+            Entries.push_back({ D, OS.tell() });
+          }
+        };
+        SmallVector<std::pair<const Decl *, uint64_t>, 8> entries;
         llvm::SmallString<128> buffer;
         llvm::SmallString<128> bufferName;
         {
@@ -397,7 +411,8 @@ void DiagnosticEngine::flushActiveDiagnostic() {
 
           // Pretty-print the declaration we've picked.
           llvm::raw_svector_ostream out(buffer);
-          ppDecl->print(out, options, &entries);
+          TrackingPrinter printer(entries, out);
+          ppDecl->print(printer, options);
         }
 
         // Build a buffer with the pretty-printed declaration.

lib/AST/Module.cpp

@@ -14,6 +14,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "swift/AST/ASTPrinter.h"
 #include "swift/AST/ASTWalker.h"
 #include "swift/AST/Diagnostics.h"
 #include "swift/AST/LazyResolver.h"
@@ -1057,12 +1058,17 @@ bool Module::walk(ASTWalker &Walker) {
 //===----------------------------------------------------------------------===//
 
 void SourceFile::print(raw_ostream &OS, const PrintOptions &PO) {
+  StreamPrinter Printer(OS);
+  print(Printer, PO);
+}
+
+void SourceFile::print(ASTPrinter &Printer, const PrintOptions &PO) {
   for (auto decl : Decls) {
     if (!decl->shouldPrintInContext(PO))
       continue;
 
-    decl->print(OS, PO);
-    OS << "\n";
+    decl->print(Printer, PO);
+    Printer << "\n";
   }
 }
 

lib/AST/TypeRepr.cpp

@@ -14,6 +14,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "swift/AST/ASTPrinter.h"
 #include "swift/AST/TypeRepr.h"
 #include "swift/AST/ASTContext.h"
 #include "swift/AST/ExprHandle.h"
@@ -59,9 +60,14 @@ void *TypeRepr::operator new(size_t Bytes, ASTContext &C, unsigned Alignment) {
   return C.Allocate(Bytes, Alignment);
 }
 
-void TypeRepr::print(raw_ostream &OS) const {
+void TypeRepr::print(raw_ostream &OS, const PrintOptions &Opts) const {
+  StreamPrinter Printer(OS);
+  print(Printer, Opts);
+}
+
+void TypeRepr::print(ASTPrinter &Printer, const PrintOptions &Opts) const {
   if (this == nullptr) {
-    OS << "<null>";
+    Printer << "<null>";
     return;
   }
 
@@ -69,36 +75,44 @@ void TypeRepr::print(raw_ostream &OS) const {
 #define TYPEREPR(CLASS, PARENT) \
   case TypeReprKind::CLASS: { \
     auto Ty = static_cast<const CLASS##TypeRepr*>(this); \
-    return Ty->printImpl(OS); \
+    return Ty->printImpl(Printer, Opts); \
   }
 #include "swift/AST/TypeReprNodes.def"
   }
   llvm_unreachable("unknown kind!");
 }
 
-void ErrorTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << "<<error type>>";
+void ErrorTypeRepr::printImpl(ASTPrinter &Printer,
+                              const PrintOptions &Opts) const {
+  Printer << "<<error type>>";
 }
 
-void AttributedTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  printAttrs(OS);
-  OS << ' ' << Ty;
+void AttributedTypeRepr::printImpl(ASTPrinter &Printer,
+                                   const PrintOptions &Opts) const {
+  printAttrs(Printer);
+  Printer << " ";
+  Ty->print(Printer, Opts);
 }
 
 void AttributedTypeRepr::printAttrs(llvm::raw_ostream &OS) const {
+  StreamPrinter Printer(OS);
+  printAttrs(Printer);
+}
+
+void AttributedTypeRepr::printAttrs(ASTPrinter &Printer) const {
   const TypeAttributes &Attrs = getAttrs();
-  if (Attrs.has(TAK_inout))        OS << "@inout ";
-  if (Attrs.has(TAK_auto_closure)) OS << "@auto_closure ";
-  if (Attrs.has(TAK_thin))         OS << "@thin ";
-  if (Attrs.has(TAK_noreturn))     OS << "@noreturn ";
-  if (Attrs.has(TAK_objc_block))   OS << "@objc_block ";
+  if (Attrs.has(TAK_inout))        Printer << "@inout ";
+  if (Attrs.has(TAK_auto_closure)) Printer << "@auto_closure ";
+  if (Attrs.has(TAK_thin))         Printer << "@thin ";
+  if (Attrs.has(TAK_noreturn))     Printer << "@noreturn ";
+  if (Attrs.has(TAK_objc_block))   Printer << "@objc_block ";
   if (Attrs.cc.hasValue()) {
     switch (Attrs.cc.getValue()) {
-    case AbstractCC::C:             OS << "@cc(cdecl)"; break;
-    case AbstractCC::ObjCMethod:    OS << "@cc(objc_method)"; break;
-    case AbstractCC::Freestanding:  OS << "@cc(freestanding)"; break;
-    case AbstractCC::Method:        OS << "@cc(method)"; break;
-    case AbstractCC::WitnessMethod: OS << "@cc(witness_method)"; break;
+    case AbstractCC::C:             Printer << "@cc(cdecl)"; break;
+    case AbstractCC::ObjCMethod:    Printer << "@cc(objc_method)"; break;
+    case AbstractCC::Freestanding:  Printer << "@cc(freestanding)"; break;
+    case AbstractCC::Method:        Printer << "@cc(method)"; break;
+    case AbstractCC::WitnessMethod: Printer << "@cc(witness_method)"; break;
     }
   }
 }
@@ -114,45 +128,66 @@ IdentTypeRepr *IdentTypeRepr::createSimple(ASTContext &C, SourceLoc Loc,
   return create(C, llvm::makeArrayRef(IdTypeComponent));
 }
 
-static void printGenericArgs(raw_ostream &OS, ArrayRef<TypeRepr *> Args) {
+static void printGenericArgs(ASTPrinter &Printer, const PrintOptions &Opts,
+                             ArrayRef<TypeRepr *> Args) {
   if (Args.empty())
     return;
 
-  OS << '<';
+  Printer << "<";
   bool First = true;
   for (auto Arg : Args) {
     if (First)
       First = false;
     else
-      OS << ", ";
-    OS << Arg;
+      Printer << ", ";
+    Arg->print(Printer, Opts);
   }
-  OS << '>';
+  Printer << ">";
 }
 
-void IdentTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << Components[0].getIdentifier();
-  printGenericArgs(OS, Components[0].getGenericArgs());
+void IdentTypeRepr::printImpl(ASTPrinter &Printer,
+                              const PrintOptions &Opts) const {
+  bool isFirst = true;
+  for (const Component &C : Components) {
+    if (!isFirst)
+      Printer << ".";
+    else
+      isFirst = false;
 
-  for (const Component &C : Components.slice(1, Components.size()-1)) {
-    OS << '.' << C.getIdentifier().get();
-    printGenericArgs(OS, C.getGenericArgs());
+    if (Module *Mod = C.getBoundModule()) {
+      Printer.printModuleRef(Mod, C.getIdentifier().str());
+    } else if (Type Ty = C.getBoundType()) {
+      if (auto NTD = Ty->getAnyNominal())
+        Printer.printTypeRef(NTD, C.getIdentifier().str());
+      else
+        Printer << C.getIdentifier().str();
+    } else {
+      Printer << C.getIdentifier().str();
+    }
+    printGenericArgs(Printer, Opts, C.getGenericArgs());
   }
 }
 
-void FunctionTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << ArgsTy << " -> " << RetTy;
+void FunctionTypeRepr::printImpl(ASTPrinter &Printer,
+                                 const PrintOptions &Opts) const {
+  ArgsTy->print(Printer, Opts);
+  Printer << " -> ";
+  RetTy->print(Printer, Opts);
 }
 
-void ArrayTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << Base << '[';
+void ArrayTypeRepr::printImpl(ASTPrinter &Printer,
+                              const PrintOptions &Opts) const {
+  Base->print(Printer, Opts);
+  Printer << "[";
   if (Size)
-    Size->getExpr()->print(OS);
-  OS << ']';
+    Size->getExpr()->print(Printer, Opts);
+  Printer << "]";
 }
 
-void OptionalTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << Base << '?';
+void OptionalTypeRepr::printImpl(ASTPrinter &Printer,
+                                 const PrintOptions &Opts) const {
+  Base->print(Printer, Opts);
+  Printer << "?";
 }
 
 TupleTypeRepr *TupleTypeRepr::create(ASTContext &C,
@@ -163,22 +198,24 @@ TupleTypeRepr *TupleTypeRepr::create(ASTContext &C,
                                Parens, Ellipsis);
 }
 
-void TupleTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << '(';
+void TupleTypeRepr::printImpl(ASTPrinter &Printer,
+                              const PrintOptions &Opts) const {
+  Printer << "(";
 
   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
-    if (i) OS << ", ";
-    OS << Elements[i];
+    if (i) Printer << ", ";
+    Elements[i]->print(Printer, Opts);
   }
   if (hasEllipsis())
-    OS << "...";
-  OS << ')';
+    Printer << "...";
+  Printer << ")";
 }
 
-void NamedTypeRepr::printImpl(llvm::raw_ostream &OS) const {
+void NamedTypeRepr::printImpl(ASTPrinter &Printer,
+                              const PrintOptions &Opts) const {
   if (!Id.empty())
-    OS << Id << " : ";
-  OS << Ty;
+    Printer << Id.str() << " : ";
+  Ty->print(Printer, Opts);
 }
 
 ProtocolCompositionTypeRepr *
@@ -190,19 +227,22 @@ ProtocolCompositionTypeRepr::create(ASTContext &C,
                                              ProtocolLoc, AngleBrackets);
 }
 
-void ProtocolCompositionTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << "protocol<";
+void ProtocolCompositionTypeRepr::printImpl(ASTPrinter &Printer,
+                                            const PrintOptions &Opts) const {
+  Printer << "protocol<";
   bool First = true;
   for (auto Proto : Protocols) {
     if (First)
       First = false;
     else
-      OS << ", ";
-    OS << Proto;
+      Printer << ", ";
+    Proto->print(Printer, Opts);
   }
-  OS << '>';
+  Printer << ">";
 }
 
-void MetaTypeTypeRepr::printImpl(llvm::raw_ostream &OS) const {
-  OS << Base << ".metatype";
+void MetaTypeTypeRepr::printImpl(ASTPrinter &Printer,
+                                 const PrintOptions &Opts) const {
+  Base->print(Printer, Opts);
+  Printer << ".metatype";
 }

lib/SIL/SILPrinter.cpp

@@ -1251,7 +1251,7 @@ void SILModule::print(llvm::raw_ostream &OS, bool Verbose,
       if ((isa<ValueDecl>(D) || isa<OperatorDecl>(D)) &&
           !emittedFunctions.count(D) &&
           !D->isImplicit()) {
-        D->print(OS, Options, nullptr);
+        D->print(OS, Options);
         OS << "\n\n";
       }
     }