'JMH using java 17, no dead code elimination

I run sample JHM benchmark which suppose to show dead code elimination. Code is rewritten for conciseness from jhm github sample.

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

@State(Scope.Thread)
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Fork(1)
public class Sample08DeadCode {

    private double x = Math.PI;

    @Benchmark
    public void benchmark() {}

    @Benchmark
    public void measureIncorrect() { Math.log(x); }

    @Benchmark
    public double measureCorrect() { return Math.log(x); }
}

Run using JDK 1.8.0_211, Java HotSpot(TM) 64-Bit Server VM, 25.211-b12 produces following results:

Benchmark                          Mode  Cnt   Score   Error  Units
Sample08DeadCode.benchmark         avgt    5   0,229 ± 0,018  ns/op
Sample08DeadCode.measureCorrect    avgt    5  12,013 ± 0,047  ns/op
Sample08DeadCode.measureIncorrect  avgt    5   0,228 ± 0,016  ns/op

but using java JDK 17.0.2, Java HotSpot(TM) 64-Bit Server VM, 17.0.2+8-LTS-86 the results have no sign of dead code elimination:

Benchmark                          Mode  Cnt  Score   Error  Units
Sample08DeadCode.benchmark         avgt    5  0,341 ± 0,004  ns/op
Sample08DeadCode.measureCorrect    avgt    5  6,244 ± 0,072  ns/op
Sample08DeadCode.measureIncorrect  avgt    5  6,263 ± 0,094  ns/op

Why does the measureIncorrect() method is not optimized using java 17?

javajmh


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