[CodeCompletion] Tiny optimization for unresolved member compilation

* Early exit for operators
* Early exit for equal types

Author: rintaro

lib/IDE/CodeCompletion.cpp

@@ -3789,6 +3789,9 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
     // same result type) as the contextual type.
     FilteredDeclConsumer consumer(*this, [=](ValueDecl *VD,
                                              DeclVisibilityKind reason) {
+      if (VD->isOperator())
+        return false;
+
       if (!VD->hasInterfaceType()) {
         TypeResolver->resolveDeclSignature(VD);
         if (!VD->hasInterfaceType())
@@ -3822,7 +3825,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
       // convertible to the contextual type.
       if (auto CD = dyn_cast<TypeDecl>(VD)) {
         declTy = declTy->getMetatypeInstanceType();
-        return swift::isConvertibleTo(declTy, T, *DC);
+        return declTy->isEqual(T) || swift::isConvertibleTo(declTy, T, *DC);
       }
 
       // Only static member can be referenced.
@@ -3839,7 +3842,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
         // FIXME: This emits just 'factory'. We should emit 'factory()' instead.
         declTy = FT->getResult();
       }
-      return swift::isConvertibleTo(declTy, T, *DC);
+      return declTy->isEqual(T) || swift::isConvertibleTo(declTy, T, *DC);
     });
 
     auto baseType = MetatypeType::get(T);