Collapse two implementations into ExistentialLayout::containsNonMarkerProtocols

Author: DougGregor

include/swift/AST/ExistentialLayout.h

@@ -105,6 +105,9 @@ struct ExistentialLayout {
   /// calling this on a temporary is likely to be incorrect.
   ArrayRef<ProtocolDecl*> getProtocols() const && = delete;
 
+  /// Determine whether this refers to any non-marker protocols.
+  bool containsNonMarkerProtocols() const;
+
   ArrayRef<ParameterizedProtocolType *> getParameterizedProtocols() const & {
     return parameterized;
   }

lib/AST/ConformanceLookup.cpp

@@ -158,7 +158,7 @@ swift::lookupExistentialConformance(Type type, ProtocolDecl *protocol) {
   // If the protocol is SendableMetatype, and there are no non-marker protocol
   // requirements, allow it via self-conformance.
   if (protocol->isSpecificProtocol(KnownProtocolKind::SendableMetatype) &&
-      !containsNonMarkerProtocols(layout.getProtocols()))
+      !layout.containsNonMarkerProtocols())
     return ProtocolConformanceRef(ctx.getSelfConformance(protocol));
 
   // We didn't find our protocol in the existential's list; it doesn't

lib/AST/Type.cpp

@@ -1186,6 +1186,15 @@ bool ExistentialLayout::isExistentialWithError(ASTContext &ctx) const {
   return false;
 }
 
+bool ExistentialLayout::containsNonMarkerProtocols() const {
+  for (auto proto : getProtocols()) {
+    if (!proto->isMarkerProtocol())
+      return true;
+  }
+
+  return false;
+}
+
 LayoutConstraint ExistentialLayout::getLayoutConstraint() const {
   if (hasExplicitAnyObject) {
     return LayoutConstraint::getLayoutConstraint(

lib/SILGen/SILGenDynamicCast.cpp

@@ -303,15 +303,6 @@ namespace {
       return CastStrategy::Address;
     }
 
-    static bool containsNonMarkerProtocols(ArrayRef<ProtocolDecl *> protocols) {
-      for (auto proto : protocols) {
-        if (!proto->isMarkerProtocol())
-          return true;
-      }
-
-      return false;
-    }
-
     CastingIsolatedConformances computedIsolatedConformances() const {
       // Non-existential types don't carry conformances, so we always allow
       // isolated conformances.
@@ -330,7 +321,7 @@ namespace {
       // If there are no non-marker protocols in the existential, there's no
       // need to prohibit isolated conformances.
       auto layout = checkType->getExistentialLayout();
-      if (!containsNonMarkerProtocols(layout.getProtocols()))
+      if (!layout.containsNonMarkerProtocols())
         return CastingIsolatedConformances::Allow;
 
       // If the type conforms to SendableMetatype, prohibit isolated