We observe a significant performance regression in the regex Pattern class for patterns containing negated character classes. The regression was introduced in JDK 9 when function objects implemented as anonymous inner classes in java.util.regex.Pattern were replaced by lambda functions.

From jdk8u to the tip, CPU utilization increases from 2.14s to 3.25s, 51.8% more. The total runtime increases from 1.84s to 3.12s, or 1.7x slower.

Test:
perf stat -r 20 java -XX:-TieredCompilation Repro on x86_64 Linux.
----------------------------
jdk8u:
          2,140.05 msec task-clock # 1.163 CPUs utilized ( +- 1.48% )
...
           1.83939 +- 0.00343 seconds time elapsed ( +- 0.19% )

----------------------------
jdk11u
          3,626.60 msec task-clock # 1.128 CPUs utilized ( +- 0.90% )
           3.21589 +- 0.00658 seconds time elapsed ( +- 0.20% )

----------------------------
tip(6d1d4d52928ed38bbc73ddcbede5389995a8e65f)
          3,257.17 msec task-clock # 1.043 CPUs utilized ( +- 0.15% )
           3.12437 +- 0.00545 seconds time elapsed ( +- 0.17% )