[GR-41453] Store FACTORY.getUncached() in static final to avoid volatile read

PullRequest: truffleruby/4529

Author: eregon

src/main/java/org/truffleruby/core/array/library/ArrayStoreLibrary.java

@@ -20,6 +20,7 @@
 import com.oracle.truffle.api.nodes.EncapsulatingNodeReference;
 import com.oracle.truffle.api.nodes.Node;
 import org.truffleruby.RubyLanguage;
+import org.truffleruby.annotations.SuppressFBWarnings;
 
 /** Library for accessing and manipulating the storage used for representing arrays. This includes reading, modifying,
  * and copy the storage. */
@@ -38,6 +39,7 @@ public abstract class ArrayStoreLibrary extends Library {
     private static final ArrayAllocator SHARED_INITIAL_ALLOCATOR = SharedArrayStorage.SHARED_ZERO_LENGTH_ARRAY_ALLOCATOR;
 
     private static final LibraryFactory<ArrayStoreLibrary> FACTORY = LibraryFactory.resolve(ArrayStoreLibrary.class);
+    private static final ArrayStoreLibrary UNCACHED = FACTORY.getUncached();
 
     public static ArrayStoreLibrary createDispatched(RubyLanguage language) {
         return FACTORY.createDispatched(language.options.ARRAY_STRATEGY_CACHE);
@@ -47,9 +49,10 @@ public static ArrayStoreLibrary create(Object store) {
         return FACTORY.create(store);
     }
 
+    @SuppressFBWarnings("MS_EXPOSE_REP")
     public static ArrayStoreLibrary getUncached() {
         CompilerAsserts.neverPartOfCompilation("uncached libraries must not be used in PE code");
-        return FACTORY.getUncached();
+        return UNCACHED;
     }
 
     public static ArrayStoreLibrary getUncached(Object store) {

src/main/java/org/truffleruby/core/klass/RubyClass.java

@@ -12,6 +12,7 @@
 import java.util.Arrays;
 import java.util.Set;
 
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.interop.InteropLibrary;
 import com.oracle.truffle.api.library.ExportLibrary;
@@ -41,7 +42,7 @@ public final class RubyClass extends RubyModule implements ObjectGraphNode {
     public final RubyDynamicObject attached;
     /* a RubyClass or nil for BasicObject */
     public final Object superclass;
-    public final RubyClass[] ancestorClasses;
+    @CompilationFinal(dimensions = 1) public final RubyClass[] ancestorClasses;
     public final ConcurrentWeakSet<RubyClass> directNonSingletonSubclasses;
     /** Depth from BasicObject (= 0) in the inheritance hierarchy. */
     public final int depth;

src/main/java/org/truffleruby/interop/BoxedValue.java

@@ -42,7 +42,7 @@ protected Object send(Message message, Object[] args,
                     "Methods should not be called on a BoxedValue as that would expose the potential Ruby object behind rather than relying on interop messages",
                     node));
         }
-        ReflectionLibrary reflection = ReflectionLibrary.getFactory().getUncached();
+        ReflectionLibrary reflection = ReflectionLibrary.getUncached();
         return reflection.send(value, message, args);
     }