Reducing chances for the object with finalizer to be reffed by register
As suggested in b/143155020#comment27
Bug: 143155020
Change-Id: I4ed87a003fcd7afde213014fc1ba8b004500e71a
diff --git a/src/com/android/launcher3/testing/TestInformationHandler.java b/src/com/android/launcher3/testing/TestInformationHandler.java
index 140a06a..64df384 100644
--- a/src/com/android/launcher3/testing/TestInformationHandler.java
+++ b/src/com/android/launcher3/testing/TestInformationHandler.java
@@ -24,9 +24,10 @@
import android.graphics.Color;
import android.os.Bundle;
import android.os.Debug;
-import android.util.Log;
import android.view.View;
+import androidx.annotation.Keep;
+
import com.android.launcher3.DeviceProfile;
import com.android.launcher3.InvariantDeviceProfile;
import com.android.launcher3.Launcher;
@@ -186,6 +187,22 @@
Runtime.getRuntime().runFinalization();
final CountDownLatch fence = new CountDownLatch(1);
+ createFinalizationObserver(fence);
+ try {
+ do {
+ Runtime.getRuntime().gc();
+ Runtime.getRuntime().runFinalization();
+ } while (!fence.await(100, TimeUnit.MILLISECONDS));
+ } catch (InterruptedException ex) {
+ throw new RuntimeException(ex);
+ }
+ }
+
+ // Create the observer in the scope of a method to minimize the chance that
+ // it remains live in a DEX/machine register at the point of the fence guard.
+ // This must be kept to avoid R8 inlining it.
+ @Keep
+ private static void createFinalizationObserver(CountDownLatch fence) {
new Object() {
@Override
protected void finalize() throws Throwable {
@@ -196,13 +213,5 @@
}
}
};
- try {
- do {
- Runtime.getRuntime().gc();
- Runtime.getRuntime().runFinalization();
- } while (!fence.await(100, TimeUnit.MILLISECONDS));
- } catch (InterruptedException ex) {
- throw new RuntimeException(ex);
- }
}
}