[llvm] [X86] Add tests showing failure to split/concat X86ISD::PCLMULQDQ nodes (PR #176179)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-aarch64-darwin` running on `doug-worker-5` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/190/builds/34376

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'cross-project-tests :: debuginfo-tests/llgdb-tests/blocks.m' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
Running debugger
Debugger output was:
imported lldb from: "/Library/Developer/CommandLineTools/Library/PrivateFrameworks/LLDB.framework/Resources/Python"
>  break 31
SBBreakpoint: id = 1, file = '/Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/blocks.m', line = 31, exact_match = 0, locations = 1
>  r
error: failed to get reply to handshake packet within timeout of 6.0 seconds
State = 3

ERROR: Could not launch process.
NOTE: There are several reasons why this may happen:
  * Root needs to run "DevToolsSecurity --enable".
  * Older versions of lldb cannot launch more than one process simultaneously.


--
Command Output (stderr):
--
/Users/buildbot/buildbot-root/aarch64-darwin/build/bin/clang --target=arm64-apple-darwin23.6.0 -O0 -g /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/blocks.m -c -o /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.o # RUN: at line 1
+ /Users/buildbot/buildbot-root/aarch64-darwin/build/bin/clang --target=arm64-apple-darwin23.6.0 -O0 -g /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/blocks.m -c -o /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.o
/Users/buildbot/buildbot-root/aarch64-darwin/build/bin/clang --target=arm64-apple-darwin23.6.0 /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.o -o /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.out -framework Foundation # RUN: at line 2
+ /Users/buildbot/buildbot-root/aarch64-darwin/build/bin/clang --target=arm64-apple-darwin23.6.0 /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.o -o /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.out -framework Foundation
PYTHON_EXEC_PATH=/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/bin/python3.9 LLDB_PYTHON_PATH=/Users/buildbot/buildbot-root/aarch64-darwin/build/./lib/python3.9/site-packages /Users/buildbot/buildbot-root/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/test_debuginfo.pl /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/blocks.m /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.out # RUN: at line 3
+ PYTHON_EXEC_PATH=/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/bin/python3.9
+ LLDB_PYTHON_PATH=/Users/buildbot/buildbot-root/aarch64-darwin/build/./lib/python3.9/site-packages
+ /Users/buildbot/buildbot-root/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/test_debuginfo.pl /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/cross-project-tests/debuginfo-tests/llgdb-tests/blocks.m /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/projects/cross-project-tests/debuginfo-tests/llgdb-tests/Output/blocks.m.tmp.out

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/176179