[CSOptimizer] NFC: Switch from llvm::Optional to std::optional post-rebase

Author: xedin

include/swift/Sema/ConstraintSystem.h

@@ -5214,7 +5214,7 @@ class ConstraintSystem {
   /// Pick a disjunction from the InactiveConstraints list.
   ///
   /// \returns The selected disjunction and a set of it's favored choices.
-  llvm::Optional<std::pair<Constraint *, llvm::TinyPtrVector<Constraint *>>>
+  std::optional<std::pair<Constraint *, llvm::TinyPtrVector<Constraint *>>>
   selectDisjunction();
 
   /// Pick a conjunction from the InactiveConstraints list.

lib/Sema/CSOptimizer.cpp

@@ -171,7 +171,7 @@ static void determineBestChoicesInContext(
 
     // Match arguments to the given overload choice.
     auto matchArguments = [&](OverloadChoice choice, FunctionType *overloadType)
-        -> llvm::Optional<MatchCallArgumentResult> {
+			-> std::optional<MatchCallArgumentResult> {
       auto *decl = choice.getDeclOrNull();
       assert(decl);
 
@@ -186,7 +186,7 @@ static void determineBestChoicesInContext(
       return matchCallArguments(argsWithLabels, overloadType->getParams(),
                                 paramListInfo,
                                 argumentList->getFirstTrailingClosureIndex(),
-                                /*allow fixes*/ false, listener, llvm::None);
+                                /*allow fixes*/ false, listener, std::nullopt);
     };
 
     // Determine whether the candidate type is a subclass of the superclass
@@ -209,15 +209,14 @@ static void determineBestChoicesInContext(
           return false;
 
         return llvm::all_of(layout.getProtocols(), [&](ProtocolDecl *P) {
-          if (auto superclass = P->getSuperclass()) {
-            if (!isSubclassOf(candidateType, superclass))
+          if (auto superclass = P->getSuperclassDecl()) {
+            if (!isSubclassOf(candidateType,
+                              superclass->getDeclaredInterfaceType()))
               return false;
           }
 
-          return bool(TypeChecker::containsProtocol(
-              candidateType, P, cs.DC->getParentModule(),
-              /*skipConditionalRequirements=*/true,
-              /*allowMissing=*/false));
+          return bool(TypeChecker::containsProtocol(candidateType, P,
+                                                    /*allowMissing=*/false));
         });
       }
 
@@ -639,13 +638,13 @@ selectBestBindingDisjunction(ConstraintSystem &cs,
   return firstBindDisjunction;
 }
 
-llvm::Optional<std::pair<Constraint *, llvm::TinyPtrVector<Constraint *>>>
+std::optional<std::pair<Constraint *, llvm::TinyPtrVector<Constraint *>>>
 ConstraintSystem::selectDisjunction() {
   SmallVector<Constraint *, 4> disjunctions;
 
   collectDisjunctions(disjunctions);
   if (disjunctions.empty())
-    return llvm::None;
+    return std::nullopt;
 
   if (auto *disjunction = selectBestBindingDisjunction(*this, disjunctions))
     return std::make_pair(disjunction, llvm::TinyPtrVector<Constraint *>());
@@ -683,5 +682,5 @@ ConstraintSystem::selectDisjunction() {
   if (bestDisjunction != disjunctions.end())
     return std::make_pair(*bestDisjunction, favorings[*bestDisjunction]);
 
-  return llvm::None;
+  return std::nullopt;
 }