src/hotspot/share/gc/cms/parNewGeneration.cpp

rev 49289 : 8199735: Mark word updates need to use Access API

*** 1,7 ****
  /*
!  * Copyright (c) 2001, 2017, 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.
--- 1,7 ----
  /*
!  * Copyright (c) 2001, 2018, 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.
*** 1131,1141 ****
    // The sequential code read "old->age()" below.  That doesn't work here,
    // since the age is in the mark word, and that might be overwritten with
    // a forwarding pointer by a parallel thread.  So we must save the mark
    // word in a local and then analyze it.
    oopDesc dummyOld;
!   dummyOld.set_mark(m);
    assert(!dummyOld.is_forwarded(),
           "should not be called with forwarding pointer mark word.");
  
    oop new_obj = NULL;
    oop forward_ptr;
--- 1131,1141 ----
    // The sequential code read "old->age()" below.  That doesn't work here,
    // since the age is in the mark word, and that might be overwritten with
    // a forwarding pointer by a parallel thread.  So we must save the mark
    // word in a local and then analyze it.
    oopDesc dummyOld;
!   dummyOld.set_mark_raw(m);
    assert(!dummyOld.is_forwarded(),
           "should not be called with forwarding pointer mark word.");
  
    oop new_obj = NULL;
    oop forward_ptr;
*** 1179,1189 ****
      // Is in to-space; do copying ourselves.
      Copy::aligned_disjoint_words((HeapWord*)old, (HeapWord*)new_obj, sz);
      assert(CMSHeap::heap()->is_in_reserved(new_obj), "illegal forwarding pointer value.");
      forward_ptr = old->forward_to_atomic(new_obj);
      // Restore the mark word copied above.
!     new_obj->set_mark(m);
      // Increment age if obj still in new generation
      new_obj->incr_age();
      par_scan_state->age_table()->add(new_obj, sz);
    }
    assert(new_obj != NULL, "just checking");
--- 1179,1189 ----
      // Is in to-space; do copying ourselves.
      Copy::aligned_disjoint_words((HeapWord*)old, (HeapWord*)new_obj, sz);
      assert(CMSHeap::heap()->is_in_reserved(new_obj), "illegal forwarding pointer value.");
      forward_ptr = old->forward_to_atomic(new_obj);
      // Restore the mark word copied above.
!     new_obj->set_mark_raw(m);
      // Increment age if obj still in new generation
      new_obj->incr_age();
      par_scan_state->age_table()->add(new_obj, sz);
    }
    assert(new_obj != NULL, "just checking");