TypeDecoder: Don't demangle freestanding PackExpansionTypes

Author: slavapestov

include/swift/AST/ASTDemangler.h

@@ -124,8 +124,6 @@ class ASTBuilder {
 
   Type createSILPackType(ArrayRef<Type> eltTypes, bool isElementAddress);
 
-  Type createPackExpansionType(Type patternType, Type countType);
-
   size_t beginPackExpansion(Type countType);
 
   void advancePackExpansion(size_t index);

include/swift/Demangling/TypeDecoder.h

@@ -1106,16 +1106,8 @@ class TypeDecoder {
     }
 
     case NodeKind::PackExpansion: {
-      if (Node->getNumChildren() < 2)
-        return MAKE_NODE_TYPE_ERROR(Node,
-                                    "fewer children (%zu) than required (2)",
-                                    Node->getNumChildren());
-
-      auto patternType = decodeMangledType(Node->getChild(0), depth + 1);
-      auto countType = decodeMangledType(Node->getChild(1), depth + 1);
-
-      return Builder.createPackExpansionType(patternType.getType(),
-                                             countType.getType());
+      return MAKE_NODE_TYPE_ERROR0(Node,
+                                   "pack expansion type in unsupported position");
     }
 
     case NodeKind::DependentGenericType: {

include/swift/RemoteInspection/TypeRefBuilder.h

@@ -758,12 +758,6 @@ class TypeRefBuilder {
     return nullptr;
   }
 
-  const TypeRef *createPackExpansionType(const TypeRef *patternType,
-                                         const TypeRef *countType) {
-    // FIXME: Remote mirrors support for variadic generics.
-    return nullptr;
-  }
-
   size_t beginPackExpansion(const TypeRef *countType) {
     // FIXME: Remote mirrors support for variadic generics.
     return 0;

lib/AST/ASTDemangler.cpp

@@ -355,10 +355,6 @@ Type ASTBuilder::createSILPackType(ArrayRef<Type> eltTypes,
   return SILPackType::get(Ctx, extInfo, elements);
 }
 
-Type ASTBuilder::createPackExpansionType(Type patternType, Type countType) {
-  return PackExpansionType::get(patternType, countType);
-}
-
 size_t ASTBuilder::beginPackExpansion(Type countType) {
   ActivePackExpansions.push_back(countType);
 

stdlib/public/runtime/MetadataLookup.cpp

@@ -2021,12 +2021,6 @@ class DecodedMetadataBuilder {
     return TYPE_LOOKUP_ERROR_FMT("Lowered SILPackType cannot be demangled");
   }
 
-  TypeLookupErrorOr<BuiltType>
-  createPackExpansionType(BuiltType patternType, BuiltType countType) const {
-    // FIXME: Runtime support for variadic generics.
-    return BuiltType();
-  }
-
   size_t beginPackExpansion(BuiltType countType) {
     if (!countType.isMetadataPack()) {
       swift::fatalError(0, "Pack expansion count type should be a pack\n");