/*

 * Copyright (c) 2014, 2015, 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.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "gc/g1/bufferingOopClosure.hpp"

#include "memory/iterator.hpp"

#include "utilities/debug.hpp"

/////////////// Unit tests ///////////////

#ifndef PRODUCT

class TestBufferingOopClosure {

  // Helper class to fake a set of oop*s and narrowOop*s.

  class FakeRoots {

   public:

    // Used for sanity checking of the values passed to the do_oops functions in the test.

    static const uintptr_t NarrowOopMarker = uintptr_t(1) << (BitsPerWord -1);

    int    _num_narrow;

    int    _num_full;

    void** _narrow;

    void** _full;

    FakeRoots(int num_narrow, int num_full) :

        _num_narrow(num_narrow),

        _num_full(num_full),

        _narrow((void**)::malloc(sizeof(void*) * num_narrow)),

        _full((void**)::malloc(sizeof(void*) * num_full)) {

      for (int i = 0; i < num_narrow; i++) {

        _narrow[i] = (void*)(NarrowOopMarker + (uintptr_t)i);

      }

      for (int i = 0; i < num_full; i++) {

        _full[i] = (void*)(uintptr_t)i;

      }

    }

    ~FakeRoots() {

      ::free(_narrow);

      ::free(_full);

    }

    void oops_do_narrow_then_full(OopClosure* cl) {

      for (int i = 0; i < _num_narrow; i++) {

        cl->do_oop((narrowOop*)_narrow[i]);

      }

      for (int i = 0; i < _num_full; i++) {

        cl->do_oop((oop*)_full[i]);

      }

    }

    void oops_do_full_then_narrow(OopClosure* cl) {

      for (int i = 0; i < _num_full; i++) {

        cl->do_oop((oop*)_full[i]);

      }

      for (int i = 0; i < _num_narrow; i++) {

        cl->do_oop((narrowOop*)_narrow[i]);

      }

    }

    void oops_do_mixed(OopClosure* cl) {

      int i;

      for (i = 0; i < _num_full && i < _num_narrow; i++) {

        cl->do_oop((oop*)_full[i]);

        cl->do_oop((narrowOop*)_narrow[i]);

      }

      for (int j = i; j < _num_full; j++) {

        cl->do_oop((oop*)_full[i]);

      }

      for (int j = i; j < _num_narrow; j++) {

        cl->do_oop((narrowOop*)_narrow[i]);

      }

    }

    static const int MaxOrder = 2;

    void oops_do(OopClosure* cl, int do_oop_order) {

      switch(do_oop_order) {

        case 0:

          oops_do_narrow_then_full(cl);

          break;

        case 1:

          oops_do_full_then_narrow(cl);

          break;

        case 2:

          oops_do_mixed(cl);

          break;

        default:

          oops_do_narrow_then_full(cl);

          break;

      }

    }

  };

  class CountOopClosure : public OopClosure {

    int _narrow_oop_count;

    int _full_oop_count;

   public:

    CountOopClosure() : _narrow_oop_count(0), _full_oop_count(0) {}

    void do_oop(narrowOop* p) {

      assert((uintptr_t(p) & FakeRoots::NarrowOopMarker) != 0,

          "The narrowOop was unexpectedly not marked with the NarrowOopMarker");

      _narrow_oop_count++;

    }

    void do_oop(oop* p){

      assert((uintptr_t(p) & FakeRoots::NarrowOopMarker) == 0,

          "The oop was unexpectedly marked with the NarrowOopMarker");

      _full_oop_count++;

    }

    int narrow_oop_count() { return _narrow_oop_count; }

    int full_oop_count()   { return _full_oop_count; }

    int all_oop_count()    { return _narrow_oop_count + _full_oop_count; }

  };

  class DoNothingOopClosure : public OopClosure {

   public:

    void do_oop(narrowOop* p) {}

    void do_oop(oop* p)       {}

  };

  static void testCount(int num_narrow, int num_full, int do_oop_order) {

    FakeRoots fr(num_narrow, num_full);

    CountOopClosure coc;

    BufferingOopClosure boc(&coc);

    fr.oops_do(&boc, do_oop_order);

    boc.done();

    assert_testCount(num_narrow, coc.narrow_oop_count());

    assert_testCount(num_full, coc.full_oop_count());

    assert_testCount(num_narrow + num_full, coc.all_oop_count());

  }

  static void testCount() {

    int buffer_length = BufferingOopClosure::BufferLength;

    for (int order = 0; order < FakeRoots::MaxOrder; order++) {

      testCount(0,                 0,                 order);

      testCount(10,                0,                 order);

      testCount(0,                 10,                order);

      testCount(10,                10,                order);

      testCount(buffer_length,     10,                order);

      testCount(10,                buffer_length,     order);

      testCount(buffer_length,     buffer_length,     order);

      testCount(buffer_length + 1, 10,                order);

      testCount(10,                buffer_length + 1, order);

      testCount(buffer_length + 1, buffer_length,     order);

      testCount(buffer_length,     buffer_length + 1, order);

      testCount(buffer_length + 1, buffer_length + 1, order);

    }

  }

  static void testIsBufferEmptyOrFull(int num_narrow, int num_full, bool expect_empty, bool expect_full) {

    FakeRoots fr(num_narrow, num_full);

    DoNothingOopClosure cl;

    BufferingOopClosure boc(&cl);

    fr.oops_do(&boc, 0);

    assert_testIsBufferEmptyOrFull(expect_empty, boc.is_buffer_empty());

    assert_testIsBufferEmptyOrFull(expect_full, boc.is_buffer_full());

  }

  static void testIsBufferEmptyOrFull() {

    int bl = BufferingOopClosure::BufferLength;

    testIsBufferEmptyOrFull(0,       0, true,  false);

    testIsBufferEmptyOrFull(1,       0, false, false);

    testIsBufferEmptyOrFull(0,       1, false, false);

    testIsBufferEmptyOrFull(1,       1, false, false);

    testIsBufferEmptyOrFull(10,      0, false, false);

    testIsBufferEmptyOrFull(0,      10, false, false);

    testIsBufferEmptyOrFull(10,     10, false, false);

    testIsBufferEmptyOrFull(0,      bl, false, true);

    testIsBufferEmptyOrFull(bl,      0, false, true);

    testIsBufferEmptyOrFull(bl/2, bl/2, false, true);

    testIsBufferEmptyOrFull(bl-1,    1, false, true);

    testIsBufferEmptyOrFull(1,    bl-1, false, true);

    // Processed

    testIsBufferEmptyOrFull(bl+1,    0, false, false);

    testIsBufferEmptyOrFull(bl*2,    0, false, true);

  }

  static void testEmptyAfterDone(int num_narrow, int num_full) {

    FakeRoots fr(num_narrow, num_full);

    DoNothingOopClosure cl;

    BufferingOopClosure boc(&cl);

    fr.oops_do(&boc, 0);

    // Make sure all get processed.

    boc.done();

    assert(boc.is_buffer_empty(),

  }

  static void testEmptyAfterDone() {

    int bl = BufferingOopClosure::BufferLength;

    testEmptyAfterDone(0,       0);

    testEmptyAfterDone(1,       0);

    testEmptyAfterDone(0,       1);

    testEmptyAfterDone(1,       1);

    testEmptyAfterDone(10,      0);

    testEmptyAfterDone(0,      10);

    testEmptyAfterDone(10,     10);

    testEmptyAfterDone(0,      bl);

    testEmptyAfterDone(bl,      0);

    testEmptyAfterDone(bl/2, bl/2);

    testEmptyAfterDone(bl-1,    1);

    testEmptyAfterDone(1,    bl-1);

    // Processed

    testEmptyAfterDone(bl+1,    0);

    testEmptyAfterDone(bl*2,    0);

  }

  public:

  static void test() {

    testCount();

    testIsBufferEmptyOrFull();

    testEmptyAfterDone();

  }

};

void TestBufferingOopClosure_test() {

  TestBufferingOopClosure::test();

}

#endif