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/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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.
*/
public class Main {
public Main() {}
// Measure adds the first and last element of the array by using ScopedPrimitiveArray.
static native long measureByteArray(long reps, byte[] arr);
static native long measureShortArray(long reps, short[] arr);
static native long measureIntArray(long reps, int[] arr);
static native long measureLongArray(long reps, long[] arr);
static void checkEq(long expected, long value) {
if (expected != value) {
System.out.println("error: Expected " + expected + " but got " + value);
}
}
static void runPerfTest(long reps) {
for (int length = 1; length <= 8192; length *= 8) {
byte[] bytes = new byte[length];
bytes[0] = 1;
bytes[length - 1] = 2;
short[] shorts = new short[length];
shorts[0] = 1;
shorts[length - 1] = 2;
int[] ints = new int[length];
ints[0] = 1;
ints[length - 1] = 2;
long[] longs = new long[length];
longs[0] = 1;
longs[length - 1] = 2;
long value = 0;
long elapsed = 0;
long start = 0;
start = System.nanoTime();
value = measureByteArray(reps, bytes);
elapsed = System.nanoTime() - start;
System.out.println("Byte length=" + length + " ns/op=" + (double) elapsed / reps);
checkEq(value, reps * (long) (bytes[0] + bytes[length - 1]));
start = System.nanoTime();
value = measureShortArray(reps, shorts);
elapsed = System.nanoTime() - start;
System.out.println("Short length=" + length + " ns/op=" + (double) elapsed / reps);
checkEq(value, reps * (long) (shorts[0] + shorts[length - 1]));
start = System.nanoTime();
value = measureIntArray(reps, ints);
elapsed = System.nanoTime() - start;
System.out.println("Int length=" + length + " ns/op=" + (double) elapsed / reps);
checkEq(value, reps * (ints[0] + ints[length - 1]));
start = System.nanoTime();
value = measureLongArray(reps, longs);
elapsed = System.nanoTime() - start;
System.out.println("Long length=" + length + " ns/op=" + (double) elapsed / reps);
checkEq(value, reps * (longs[0] + longs[length - 1]));
}
}
public static void main(String[] args) {
System.loadLibrary(args[0]);
long iterations = 2000000;
if (args.length > 1) {
iterations = Long.parseLong(args[1], 10);
}
runPerfTest(iterations);
System.out.println("Done");
}
}
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