/*

 * Copyright (c) 2013, 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/g1BiasedArray.hpp"

#include "memory/padded.inline.hpp"

// Allocate a new array, generic version.

address G1BiasedMappedArrayBase::create_new_base_array(size_t length, size_t elem_size) {

  assert(length > 0, "just checking");

  assert(elem_size > 0, "just checking");

  return PaddedPrimitiveArray<u_char, mtGC>::create_unfreeable(length * elem_size);

}

#ifndef PRODUCT

void G1BiasedMappedArrayBase::verify_index(idx_t index) const {

  guarantee(_base != NULL, "Array not initialized");

  guarantee(index < length(), "Index out of bounds index: " SIZE_FORMAT " length: " SIZE_FORMAT, index, length());

}

void G1BiasedMappedArrayBase::verify_biased_index(idx_t biased_index) const {

  guarantee(_biased_base != NULL, "Array not initialized");

  guarantee(biased_index >= bias() && biased_index < (bias() + length()),

            "Biased index out of bounds, index: " SIZE_FORMAT " bias: " SIZE_FORMAT " length: " SIZE_FORMAT,

            biased_index, bias(), length());

}

void G1BiasedMappedArrayBase::verify_biased_index_inclusive_end(idx_t biased_index) const {

  guarantee(_biased_base != NULL, "Array not initialized");

  guarantee(biased_index >= bias() && biased_index <= (bias() + length()),

            "Biased index out of inclusive bounds, index: " SIZE_FORMAT " bias: " SIZE_FORMAT " length: " SIZE_FORMAT,

            biased_index, bias(), length());

}

class TestMappedArray : public G1BiasedMappedArray<int> {

protected:

  virtual int default_value() const { return 0xBAADBABE; }

public:

  static void test_biasedarray() {

    const size_t REGION_SIZE_IN_WORDS = 512;

    const size_t NUM_REGIONS = 20;

    HeapWord* fake_heap = (HeapWord*)LP64_ONLY(0xBAAA00000) NOT_LP64(0xBA000000); // Any value that is non-zero

    TestMappedArray array;

    array.initialize(fake_heap, fake_heap + REGION_SIZE_IN_WORDS * NUM_REGIONS,

            REGION_SIZE_IN_WORDS * HeapWordSize);

    // Check address calculation (bounds)

    assert(array.bottom_address_mapped() == fake_heap,

           "bottom mapped address should be " PTR_FORMAT ", but is " PTR_FORMAT, p2i(fake_heap), p2i(array.bottom_address_mapped()));

    assert(array.end_address_mapped() == (fake_heap + REGION_SIZE_IN_WORDS * NUM_REGIONS), "must be");

    int* bottom = array.address_mapped_to(fake_heap);

    assert((void*)bottom == (void*) array.base(), "must be");

    int* end = array.address_mapped_to(fake_heap + REGION_SIZE_IN_WORDS * NUM_REGIONS);

    assert((void*)end == (void*)(array.base() + array.length()), "must be");

    // The entire array should contain default value elements

    for (int* current = bottom; current < end; current++) {

      assert(*current == array.default_value(), "must be");

    }

    // Test setting values in the table

    HeapWord* region_start_address = fake_heap + REGION_SIZE_IN_WORDS * (NUM_REGIONS / 2);

    HeapWord* region_end_address = fake_heap + (REGION_SIZE_IN_WORDS * (NUM_REGIONS / 2) + REGION_SIZE_IN_WORDS - 1);

    // Set/get by address tests: invert some value; first retrieve one

    int actual_value = array.get_by_index(NUM_REGIONS / 2);

    array.set_by_index(NUM_REGIONS / 2, ~actual_value);

    // Get the same value by address, should correspond to the start of the "region"

    int value = array.get_by_address(region_start_address);

    assert(value == ~actual_value, "must be");

    // Get the same value by address, at one HeapWord before the start

    value = array.get_by_address(region_start_address - 1);

    assert(value == array.default_value(), "must be");

    // Get the same value by address, at the end of the "region"

    value = array.get_by_address(region_end_address);

    assert(value == ~actual_value, "must be");

    // Make sure the next value maps to another index

    value = array.get_by_address(region_end_address + 1);

    assert(value == array.default_value(), "must be");

    // Reset the value in the array

    array.set_by_address(region_start_address + (region_end_address - region_start_address) / 2, actual_value);

    // The entire array should have the default value again

    for (int* current = bottom; current < end; current++) {

      assert(*current == array.default_value(), "must be");

    }

    // Set/get by index tests: invert some value

    idx_t index = NUM_REGIONS / 2;

    actual_value = array.get_by_index(index);

    array.set_by_index(index, ~actual_value);

    value = array.get_by_index(index);

    assert(value == ~actual_value, "must be");

    value = array.get_by_index(index - 1);

    assert(value == array.default_value(), "must be");

    value = array.get_by_index(index + 1);

    assert(value == array.default_value(), "must be");

    array.set_by_index(0, 0);

    value = array.get_by_index(0);

    assert(value == 0, "must be");

    array.set_by_index(array.length() - 1, 0);

    value = array.get_by_index(array.length() - 1);

    assert(value == 0, "must be");

    array.set_by_index(index, 0);

    // The array should have three zeros, and default values otherwise

    size_t num_zeros = 0;

    for (int* current = bottom; current < end; current++) {

      assert(*current == array.default_value() || *current == 0, "must be");

      if (*current == 0) {

        num_zeros++;

      }

    }

    assert(num_zeros == 3, "must be");

  }

};

void TestG1BiasedArray_test() {

  TestMappedArray::test_biasedarray();

}

#endif