[jdk8u-dev] RFR: 8202952: C2: Unexpected dead nodes after matching [v2]

[Dongbo He]

> I would like to backport this patch to fix crash during C2 compilation. 
> 
> This patch doesn't apply cleanly due to context differences, and
> I selected fuzzer tests from Fei Yang because the tests in the original commit cannot be reproduced on JDK8u.
> 
> Performed hotspot jtreg test on linux x86-64 platforms with -Xcomp options, new test fails without product change and passes with it.

Dongbo He has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge branch 'master' into 8202952
 - Backport 50e3aa4150dc1dd18870c5725666188ab38ab7d5

-------------

Changes:
  - all: https://git.openjdk.org/jdk8u-dev/pull/291/files
  - new: https://git.openjdk.org/jdk8u-dev/pull/291/files/ef05c21c..b86159a7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=291&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=291&range=00-01

  Stats: 908048 lines in 377 files changed: 904339 ins; 1874 del; 1835 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/291.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/291/head:pull/291

PR: https://git.openjdk.org/jdk8u-dev/pull/291