AST: Add HasComputedAssociatedConformancesFlag to NormalProtocolConformance

Author: slavapestov

include/swift/AST/ProtocolConformance.h

@@ -444,13 +444,18 @@ class NormalProtocolConformance : public RootProtocolConformance,
 
     /// The conformance was labeled with @unchecked.
     UncheckedFlag = 0x02,
+
+    /// We have allocated the AssociatedConformances array (but not necessarily
+    /// populated any of its elements).
+    HasComputedAssociatedConformancesFlag = 0x04,
   };
 
   /// The declaration context containing the ExtensionDecl or
   /// NominalTypeDecl that declared the conformance.
   ///
-  /// Also stores the "invalid" and "unchecked" bits.
-  llvm::PointerIntPair<DeclContext *, 2, unsigned> ContextAndBits;
+  /// Also stores the "invalid", "unchecked" and "has computed associated
+  /// conformances" bits.
+  llvm::PointerIntPair<DeclContext *, 3, unsigned> ContextAndBits;
 
   /// The reason that this conformance exists.
   ///
@@ -554,6 +559,17 @@ class NormalProtocolConformance : public RootProtocolConformance,
     ContextAndBits.setInt(ContextAndBits.getInt() | UncheckedFlag);
   }
 
+  /// Determine whether we've lazily computed the associated conformance array
+  /// already.
+  bool hasComputedAssociatedConformances() const {
+    return ContextAndBits.getInt() & HasComputedAssociatedConformancesFlag;
+  }
+
+  /// Mark this conformance as having computed the assocaited conformance array.
+  void setHasComputedAssociatedConformances() {
+    ContextAndBits.setInt(ContextAndBits.getInt() | HasComputedAssociatedConformancesFlag);
+  }
+
   /// Get the kind of source from which this conformance comes.
   ConformanceEntryKind getSourceKind() const {
     return SourceKindAndImplyingConformance.getInt();

lib/AST/ProtocolConformance.cpp

@@ -535,14 +535,14 @@ Type ProtocolConformance::getAssociatedType(Type assocType) const {
 
 ProtocolConformanceRef
 ProtocolConformance::getAssociatedConformance(Type assocType,
-                                               ProtocolDecl *protocol) const {
+                                              ProtocolDecl *protocol) const {
   CONFORMANCE_SUBCLASS_DISPATCH(getAssociatedConformance,
                                 (assocType, protocol))
 }
 
 ProtocolConformanceRef
 NormalProtocolConformance::getAssociatedConformance(Type assocType,
-                                                ProtocolDecl *protocol) const {
+                                                 ProtocolDecl *protocol) const {
   assert(assocType->isTypeParameter() &&
          "associated type must be a type parameter");