/*
 * Copyright (C) 2016 Linaro Limited.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 * Description:     Tracks performance of accessing array locations using variables and constants
 *                  as indexes.
 * Main Focus:      Memory accesses using arrays.
 *
 */

package org.linaro.benchmarks.micro;

import org.openjdk.jmh.annotations.*;
import java.util.concurrent.TimeUnit;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@State(Scope.Benchmark)

public class ArrayAccess {

  private static final int ITER_COUNT = 1000;
  private int[] array = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

  public static void accessArrayConstants(int[] array) {
    for (int j = 0; j < 100000; j++) {
      array[4]++;
      array[5]++;
    }
  }

  public static void accessArrayVariables(int[] array, int i) {
    for (int j = 0; j < 100000; j++) {
      array[i]++;
      array[i + 1]++;
      array[i + 2]++;
      array[i - 2]++;
      array[i - 1]++;
    }
  }

  @Benchmark
  public void jmhTimeAccessArrayConstants() {
    for (int i = 0; i < 1000; i++) {
      accessArrayConstants(array);
    }
  }

  @Benchmark
  public void jmhTimeAccessArrayVariables() {
    for (int i = 0; i < 1000; i++) {
      accessArrayVariables(array, 5);
    }
  }
}