/*
    * Copyright 2026 The Netty Project
    *
    * The Netty Project licenses this file to you 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:
    *
    *   https://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.
   */
  package io.netty.buffer;
  
  import io.netty.microbench.util.AbstractMicrobenchmark;
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.Fork;
  import org.openjdk.jmh.annotations.Measurement;
  import org.openjdk.jmh.annotations.Mode;
  import org.openjdk.jmh.annotations.OutputTimeUnit;
  import org.openjdk.jmh.annotations.Setup;
  import org.openjdk.jmh.annotations.TearDown;
  import org.openjdk.jmh.annotations.Warmup;
  
  import java.util.concurrent.TimeUnit;
  
  @Warmup(iterations = 5)
  @Measurement(iterations = 5)
  @BenchmarkMode(Mode.AverageTime)
  @OutputTimeUnit(TimeUnit.NANOSECONDS)
  public class VarHandleAccessBenchmark extends AbstractMicrobenchmark {
  
      private ByteBuf unsafeDirect;
      private ByteBuf unsafeHeap;
  
      @Setup
      public void setup() {
          unsafeDirect = new UnpooledUnsafeDirectByteBuf(ByteBufAllocator.DEFAULT, 8, 8);
          unsafeHeap = new UnpooledUnsafeHeapByteBuf(ByteBufAllocator.DEFAULT, 8, 8);
          unsafeDirect.setLong(0, 1L);
          unsafeHeap.setLong(0, 1L);
      }
  
      @TearDown
      public void tearDown() {
          unsafeDirect.release();
          unsafeHeap.release();
      }
  
      // UNALIGNED = false: should use VarHandle for multi-byte access
      @Benchmark
      @Fork(value = 1, jvmArgsAppend = "-Dio.netty.unalignedAccess=false")
      public long getLongDirectFalse() {
          return unsafeDirect.getLong(0);
      }
  
      @Benchmark
      @Fork(value = 1, jvmArgsAppend = "-Dio.netty.unalignedAccess=false")
      public long getLongHeapFalse() {
          return unsafeHeap.getLong(0);
      }
  }