Performance regression after fix for JDK-8229496

ADDITIONAL SYSTEM INFORMATION :
CPU: Intel 8700k
RAM: 64GB
Win10 x64 1909 / 18363.720

VM version: JDK 14, OpenJDK 64-Bit Server VM, 14+36-1461
VM version: JDK 13.0.2, OpenJDK 64-Bit Server VM, 13.0.2+8


A DESCRIPTION OF THE PROBLEM :
Using ojdk14 gives a performance penalty around 5 to 15% using NumberFormat.format.

JMH Benchmark results:

# JMH version: 1.23
# VM version: JDK 14, OpenJDK 64-Bit Server VM, 14+36-1461
# VM invoker: C:\Program Files\Java\ojdk-14\bin\java.exe
# VM options: -Dfile.encoding=UTF-8 --module-path=E:\Profile\eclipse\jdk11\de.sph.benchmark3\target\classes;C:\Users\Stefa\.m2\repository\org\openjdk\jmh\jmh-core\1.23\jmh-core-1.23.jar -Djdk.module.main=de.sph.benchmark3
# Warmup: 5 iterations, 5 s each
# Measurement: 5 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: de.sph.benchmark3.DefFormatterBench.testDefNumberFormatter

Benchmark (value) Mode Cnt Score Error Units
DefFormatterBench.testDefNumberFormatter 1.23 thrpt 5 6020,498 ± 315,527 ops/ms
DefFormatterBench.testDefNumberFormatter 1.49 thrpt 5 5981,606 ± 185,040 ops/ms
DefFormatterBench.testDefNumberFormatter 1.80 thrpt 5 6894,794 ± 252,732 ops/ms
DefFormatterBench.testDefNumberFormatter 1.7 thrpt 5 6760,995 ± 251,076 ops/ms
DefFormatterBench.testDefNumberFormatter 0.0 thrpt 5 10398,507 ± 225,129 ops/ms
DefFormatterBench.testDefNumberFormatter -1.49 thrpt 5 5572,113 ± 47,249 ops/ms
DefFormatterBench.testDefNumberFormatter -1.50 thrpt 5 6223,956 ± 140,064 ops/ms
DefFormatterBench.testDefNumberFormatter 9999.9123 thrpt 5 3534,608 ± 40,504 ops/ms
DefFormatterBench.testDefNumberFormatter 1.494 thrpt 5 5314,769 ± 23,540 ops/ms
DefFormatterBench.testDefNumberFormatter 1.495 thrpt 5 5503,352 ± 29,010 ops/ms
DefFormatterBench.testDefNumberFormatter 1.03 thrpt 5 6094,022 ± 404,048 ops/ms
DefFormatterBench.testDefNumberFormatter 25.996 thrpt 5 4653,838 ± 72,346 ops/ms
DefFormatterBench.testDefNumberFormatter -25.996 thrpt 5 4408,712 ± 33,991 ops/ms

-------------------
# JMH version: 1.23
# VM version: JDK 13.0.2, OpenJDK 64-Bit Server VM, 13.0.2+8
# VM invoker: C:\Program Files\Java\ojdk-13.0.2\bin\java.exe
# VM options: -Dfile.encoding=UTF-8 --module-path=E:\Profile\eclipse\jdk11\de.sph.benchmark3\target\classes;C:\Users\Stefa\.m2\repository\org\openjdk\jmh\jmh-core\1.23\jmh-core-1.23.jar -Djdk.module.main=de.sph.benchmark3
# Warmup: 5 iterations, 5 s each
# Measurement: 5 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: de.sph.benchmark3.DefFormatterBench.testDefNumberFormatter

Benchmark (value) Mode Cnt Score Error Units
DefFormatterBench.testDefNumberFormatter 1.23 thrpt 5 6758,121 ± 22,820 ops/ms
DefFormatterBench.testDefNumberFormatter 1.49 thrpt 5 6696,395 ± 649,326 ops/ms
DefFormatterBench.testDefNumberFormatter 1.80 thrpt 5 7526,417 ± 70,981 ops/ms
DefFormatterBench.testDefNumberFormatter 1.7 thrpt 5 7216,894 ± 751,324 ops/ms
DefFormatterBench.testDefNumberFormatter 0.0 thrpt 5 10974,451 ± 1662,661 ops/ms
DefFormatterBench.testDefNumberFormatter -1.49 thrpt 5 6236,206 ± 451,509 ops/ms
DefFormatterBench.testDefNumberFormatter -1.50 thrpt 5 6669,078 ± 485,808 ops/ms
DefFormatterBench.testDefNumberFormatter 9999.9123 thrpt 5 4156,953 ± 25,838 ops/ms
DefFormatterBench.testDefNumberFormatter 1.494 thrpt 5 6126,089 ± 61,211 ops/ms
DefFormatterBench.testDefNumberFormatter 1.495 thrpt 5 6025,925 ± 447,987 ops/ms
DefFormatterBench.testDefNumberFormatter 1.03 thrpt 5 6916,877 ± 26,122 ops/ms
DefFormatterBench.testDefNumberFormatter 25.996 thrpt 5 5363,537 ± 16,783 ops/ms
DefFormatterBench.testDefNumberFormatter -25.996 thrpt 5 4931,153 ± 35,624 ops/ms
-------------------------------------------
Test code:
package de.sph.benchmark3;

import java.text.NumberFormat;
import java.util.Locale;
import java.util.concurrent.TimeUnit;

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.Param;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.infra.Blackhole;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;

@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@Warmup(iterations = 5, time = 5, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 10, timeUnit = TimeUnit.SECONDS)
@Fork(1)
@State(Scope.Benchmark)
public class DefFormatterBench {

@Param({ "1.23", "1.49", "1.80", "1.7", "0.0", "-1.49", "-1.50", "9999.9123", "1.494", "1.495", "1.03", "25.996",
"-25.996" })
public double value;

private DefNumerFormat dnf = new DefNumerFormat();

@Benchmark
public void testDefNumberFormatter(final Blackhole blackhole) {
blackhole.consume(this.dnf.format(this.value));
}

public static void main(String... args) throws Exception {

Options opts = new OptionsBuilder().include(DefFormatterBench.class.getSimpleName()).shouldDoGC(true).build();

new Runner(opts).run();
}

private static class DefNumerFormat {
private final NumberFormat n;

public DefNumerFormat() {
this.n = NumberFormat.getInstance(Locale.ENGLISH);
this.n.setMaximumFractionDigits(2);
this.n.setMinimumFractionDigits(2);
this.n.setGroupingUsed(false);
}

public String format(final double d) {
return this.n.format(d);
}
}
}