[jdk8u-dev] RFR: 8255466: C2 crashes at ciObject::get_oop() const+0x0 [v2]

[SendaoYan]

> Hi all,
> This is backport of JDK-8255466, to fixes the corner case in C2. This PR also fix the compiler warning `hotspot/src/share/vm/opto/type.cpp:2556:71: error: ‘this’ pointer is null` with gcc13.
> Patch does not apply cleanly due to in jdk8u, the jtreg tag @run main need add `bootclasspath`.
> New test fails without the patch, passes with it.
> 
> Additional testing:
> 
> - [x] linux x64 tier1/2/3 jtreg test
> - [x] linux aarch64 tier1/2/3 jtreg test

SendaoYan has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains four commits:

 - Remove extra whitespace
 - Remove extra empty space
 - Merge branch 'master' into jbs8255466
 - Backport bb3f1238cb12c45ed85936d3b06eced0730d588f

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Changes: https://git.openjdk.org/jdk8u-dev/pull/536/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=536&range=01
  Stats: 67 lines in 2 files changed: 63 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/536.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/536/head:pull/536

PR: https://git.openjdk.org/jdk8u-dev/pull/536