test/hotspot/jtreg/vmTestbase/nsk/share/gc/Memory.java

@@ -1,7 +1,7 @@
  /*
-  * Copyright (c) 2005, 2024, Oracle and/or its affiliates. All rights reserved.
+  * Copyright (c) 2005, 2026, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.

@@ -25,21 +25,25 @@
  
  import nsk.share.test.LocalRandom;
  import java.io.PrintStream;
  import nsk.share.gc.gp.GarbageProducer;
  import nsk.share.gc.tree.*;
- import nsk.share.gc.gp.MemoryStrategy;
  import nsk.share.log.Log;
  
  /**
   *  Different utility methods to work with memory objects.
   */
  public final class Memory {
          private static int bits = 0;
          private static int referenceSize = 0;
          private static int objectExtraSize = 0;
  
+         private static final boolean previewEnabled =
+                 System.getProperty("test.java.opts", "").contains("--enable-preview") ||
+                 System.getProperty("test.vm.opts", "").contains("--enable-preview");
+ 
+ 
          private Memory() {
          }
  
          private static int getBits() {
                  if (bits == 0)

@@ -56,10 +60,18 @@
                  if (referenceSize == 0)
                          referenceSize = (getBits() == 64) ? 8 : 4;
                  return referenceSize;
          }
  
+         public static boolean isPreviewEnabled() {
+                 return previewEnabled;
+         }
+ 
+         public static boolean isValhallaEnabled() {
+             return previewEnabled;
+         }
+ 
          /**
           * Get size of primitive type int.
           */
          public static int getIntSize() {
                  return 4;

@@ -113,10 +125,50 @@
          public static int getDoubleSize() {
                  return 8;
          }
  
          /**
+          * Get size of Integer element in Integer array.
+          * If array is not flattened, the only reference size is returned, the referred values
+          * should be added manually in references are not null.
+          */
+         public static int getIntegerArrayElementSize() {
+ 
+             if (!Memory.isValhallaEnabled()) {
+                 return getReferenceSize();
+             }
+             return 8;
+         }
+ 
+         /**
+          * Get size of Byte element in Byte array.
+          * If array is not flattened, the only reference size is returned, the referred values
+          * should be added manually in references are not null.
+          */
+         public static int getByteArrayElementSize() {
+ 
+             if (!Memory.isValhallaEnabled()) {
+                 return getReferenceSize();
+             }
+             return 2;
+         }
+ 
+         /**
+          * Get size of Boolean element in Boolean array.
+          * If array is not flattened, the only reference size is returned, the referred values
+          * should be added manually in references are not null.
+          */
+         public static int getBooleanArrayElementSize() {
+             if (!Memory.isValhallaEnabled()) {
+                 return getReferenceSize();
+             }
+             return 2;
+         }
+ 
+ 
+ 
+     /**
           *  Get how many extra bytes an object occupies in the heap
           *  compared to sum of it's fields.
           *
           *  TODO: somehow determine the real value
           */

@@ -149,12 +201,13 @@
           *  @param objectSize size of each object in array
           *  @return length of array
           */
          public static int getArrayLength(long memory, long objectSize) {
                  int arrayExtraSize = getArrayExtraSize();
-                 return (int) Math.min((memory - arrayExtraSize) / objectSize,
+                 int length = (int) Math.min((memory - arrayExtraSize) / objectSize,
                          Integer.MAX_VALUE);
+                 return Math.max(length, 0);
          }
  
          /**
           *  Get an approximate size of array of given length and object size.
           *