spare cpu cycles during indexing by not allocating tons of NonCancelableIndicator and not calculating their native hashCode

platform/core-impl/src/com/intellij/openapi/progress/impl/CoreProgressManager.java

@@ -167,7 +167,7 @@ public class CoreProgressManager extends ProgressManager implements Disposable {
 
   @Override
   public void executeNonCancelableSection(@NotNull Runnable runnable) {
-    executeProcessUnderProgress(runnable, new NonCancelableIndicator());
+    executeProcessUnderProgress(runnable, NonCancelableIndicator.INSTANCE);
   }
 
   @Override

platform/core-impl/src/com/intellij/openapi/progress/impl/NonCancelableIndicator.java

@@ -23,6 +23,16 @@ import com.intellij.openapi.progress.StandardProgressIndicator;
 import org.jetbrains.annotations.NotNull;
 
 class NonCancelableIndicator implements NonCancelableSection, StandardProgressIndicator {
+  static final NonCancelableIndicator INSTANCE = new NonCancelableIndicator() {
+    @Override
+    public int hashCode() {
+      return 0;
+    }
+  };
+
+  protected NonCancelableIndicator() {
+  }
+
   @Override
   public void done() {
     ProgressIndicator currentIndicator = ProgressManager.getInstance().getProgressIndicator();