RFR: 8304138: [JVMCI] Test FailedSpeculation existence before appending.

Tue Mar 14 15:09:25 UTC 2023

Upon uncommon_trap, JVMCI runtime appends a FailedSpeculation entry to the nmethod using an [atomic operation](https://github.com/openjdk/jdk/blob/55aa122462c34d8f4cafa58f4d1f2d900449c83e/src/hotspot/share/oops/methodData.cpp#L852). It becomes a performance bottleneck when there is a large amount of (virtual) threads deoptimizing in the nmethod. In this PR, we test if a FailedSpeculation exists in the list before appending it.

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Commit messages:
 - [JVMCI] Test FailedSpeculation existence before appending.

Changes: https://git.openjdk.org/jdk/pull/13022/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13022&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304138
  Stats: 10 lines in 1 file changed: 9 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/13022.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/13022/head:pull/13022

PR: https://git.openjdk.org/jdk/pull/13022