[AST] Added hasConcretePack recursive property.

Author: nate-chandler

include/swift/AST/Types.h

@@ -173,7 +173,10 @@ class RecursiveTypeProperties {
     /// This type contains an ElementArchetype.
     HasElementArchetype = 0x4000,
 
-    Last_Property = HasElementArchetype
+    /// This type contains a concrete pack.
+    HasConcretePack = 0x8000,
+
+    Last_Property = HasConcretePack
   };
   enum { BitWidth = countBitsUsed(Property::Last_Property) };
 
@@ -243,6 +246,8 @@ class RecursiveTypeProperties {
 
   bool hasParameterPack() const { return Bits & HasParameterPack; }
 
+  bool hasConcretePack() const { return Bits & HasConcretePack; }
+
   /// Does a type with these properties structurally contain a
   /// parameterized existential type?
   bool hasParameterizedExistential() const {
@@ -670,6 +675,13 @@ class alignas(1 << TypeAlignInBits) TypeBase
     return getRecursiveProperties().hasParameterPack();
   }
 
+  bool hasConcretePack() const {
+    return getRecursiveProperties().hasConcretePack();
+  }
+
+  /// Whether the type has some flavor of pack.
+  bool hasPack() const { return hasParameterPack() || hasConcretePack(); }
+
   /// Determine whether the type involves a parameterized existential type.
   bool hasParameterizedExistential() const {
     return getRecursiveProperties().hasParameterizedExistential();

lib/AST/ASTContext.cpp

@@ -3312,7 +3312,7 @@ CanPackType CanPackType::get(const ASTContext &C,
 }
 
 PackType *PackType::get(const ASTContext &C, ArrayRef<Type> elements) {
-  RecursiveTypeProperties properties;
+  RecursiveTypeProperties properties = RecursiveTypeProperties::HasConcretePack;
   bool isCanonical = true;
   for (Type eltTy : elements) {
     assert(!eltTy->is<PackType>() &&
@@ -3352,7 +3352,7 @@ void PackType::Profile(llvm::FoldingSetNodeID &ID, ArrayRef<Type> Elements) {
 
 CanSILPackType SILPackType::get(const ASTContext &C, ExtInfo info,
                                 ArrayRef<CanType> elements) {
-  RecursiveTypeProperties properties;
+  RecursiveTypeProperties properties = RecursiveTypeProperties::HasConcretePack;
   for (CanType eltTy : elements) {
     assert(!isa<SILPackType>(eltTy) &&
            "Cannot have pack directly inside another pack");
@@ -3944,7 +3944,7 @@ isAnyFunctionTypeCanonical(ArrayRef<AnyFunctionType::Param> params,
 static RecursiveTypeProperties
 getGenericFunctionRecursiveProperties(ArrayRef<AnyFunctionType::Param> params,
                                       Type result) {
-  static_assert(RecursiveTypeProperties::BitWidth == 15,
+  static_assert(RecursiveTypeProperties::BitWidth == 16,
                 "revisit this if you add new recursive type properties");
   RecursiveTypeProperties properties;
 
@@ -4604,7 +4604,7 @@ CanSILFunctionType SILFunctionType::get(
   void *mem = ctx.Allocate(bytes, alignof(SILFunctionType));
 
   RecursiveTypeProperties properties;
-  static_assert(RecursiveTypeProperties::BitWidth == 15,
+  static_assert(RecursiveTypeProperties::BitWidth == 16,
                 "revisit this if you add new recursive type properties");
   for (auto &param : params)
     properties |= param.getInterfaceType()->getRecursiveProperties();