src/java.base/share/classes/jdk/internal/misc/Unsafe.java

rev 57826 : 8237521: Memory Access API fixes for 32-bit
Reviewed-by: mcimadamore, dholmes

*** 1,7 ****
  /*
!  * Copyright (c) 2000, 2019, 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.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2000, 2020, 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.  Oracle designates this
*** 582,591 ****
--- 582,602 ----
  
  
      /// wrappers for malloc, realloc, free:
  
      /**
+      * Round up allocation size to a multiple of HeapWordSize.
+      */
+     private long alignToHeapWordSize(long bytes) {
+         if (bytes >= 0) {
+             return (bytes + ADDRESS_SIZE - 1) & ~(ADDRESS_SIZE - 1);
+         } else {
+             throw invalidInput();
+         }
+     }
+ 
+     /**
       * Allocates a new block of native memory, of the given size in bytes.  The
       * contents of the memory are uninitialized; they will generally be
       * garbage.  The resulting native pointer will never be zero, and will be
       * aligned for all value types.  Dispose of this memory by calling {@link
       * #freeMemory}, or resize it with {@link #reallocateMemory}.
*** 606,615 ****
--- 617,628 ----
       *
       * @see #getByte(long)
       * @see #putByte(long, byte)
       */
      public long allocateMemory(long bytes) {
+         bytes = alignToHeapWordSize(bytes);
+ 
          allocateMemoryChecks(bytes);
  
          if (bytes == 0) {
              return 0;
          }
*** 659,668 ****
--- 672,683 ----
       * @throws OutOfMemoryError if the allocation is refused by the system
       *
       * @see #allocateMemory
       */
      public long reallocateMemory(long address, long bytes) {
+         bytes = alignToHeapWordSize(bytes);
+ 
          reallocateMemoryChecks(address, bytes);
  
          if (bytes == 0) {
              freeMemory(address);
              return 0;