[llvm] [SLP][REVEC] reorderNodeWithReuses should not be called if all users of a TreeEntry are ShuffleVectorInst. (PR #118260)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `libc-x86_64-debian-gcc-fullbuild-dbg` running on `libc-x86_64-debian-fullbuild` while building `llvm` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/131/builds/11538

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

```
Step 4 (annotate) failure: 'python ../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py ...' (failure)
...
[       OK ] LlvmLibcMlockTest.MLockAll (1 ms)
Ran 5 tests.  PASS: 5  FAIL: 0
[936/1103] Running unit test libc.test.src.sys.mman.linux.shm_test
[==========] Running 2 tests from 1 test suite.
[ RUN      ] LlvmLibcShmTest.Basic
[       OK ] LlvmLibcShmTest.Basic (151 us)
[ RUN      ] LlvmLibcShmTest.NameConversion
[       OK ] LlvmLibcShmTest.NameConversion (52 us)
Ran 2 tests.  PASS: 2  FAIL: 0
[937/1103] Running unit test libc.test.src.sys.mman.linux.process_mrelease_test
FAILED: projects/libc/test/src/sys/mman/linux/CMakeFiles/libc.test.src.sys.mman.linux.process_mrelease_test /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-gcc-fullbuild-dbg/build/projects/libc/test/src/sys/mman/linux/CMakeFiles/libc.test.src.sys.mman.linux.process_mrelease_test 
cd /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-gcc-fullbuild-dbg/build/projects/libc/test/src/sys/mman/linux && /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-gcc-fullbuild-dbg/build/projects/libc/test/src/sys/mman/linux/libc.test.src.sys.mman.linux.process_mrelease_test.__build__
[==========] Running 3 tests from 1 test suite.
[ RUN      ] LlvmLibcProcessMReleaseTest.NoError
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-gcc-fullbuild-dbg/llvm-project/libc/test/src/sys/mman/linux/process_mrelease_test.cpp:44: FAILURE
Failed to match LIBC_NAMESPACE::process_mrelease(pidfd, 0) against Succeeds().
Expected return value to be equal to 0 but got -1.
Expected errno to be equal to "Success" but got "No such process".
[  FAILED  ] LlvmLibcProcessMReleaseTest.NoError
[ RUN      ] LlvmLibcProcessMReleaseTest.ErrorNotKilled
[       OK ] LlvmLibcProcessMReleaseTest.ErrorNotKilled (128 us)
[ RUN      ] LlvmLibcProcessMReleaseTest.ErrorNonExistingPidfd
[       OK ] LlvmLibcProcessMReleaseTest.ErrorNonExistingPidfd (7 us)
Ran 3 tests.  PASS: 2  FAIL: 1
[938/1103] Running unit test libc.test.src.sys.random.linux.getrandom_test
[==========] Running 4 tests from 1 test suite.
[ RUN      ] LlvmLibcGetRandomTest.InvalidFlag
[       OK ] LlvmLibcGetRandomTest.InvalidFlag (4 us)
[ RUN      ] LlvmLibcGetRandomTest.InvalidBuffer
[       OK ] LlvmLibcGetRandomTest.InvalidBuffer (6 us)
[ RUN      ] LlvmLibcGetRandomTest.ReturnsSize
[       OK ] LlvmLibcGetRandomTest.ReturnsSize (17 us)
[ RUN      ] LlvmLibcGetRandomTest.CheckValue
[       OK ] LlvmLibcGetRandomTest.CheckValue (6 us)
Ran 4 tests.  PASS: 4  FAIL: 0
[939/1103] Running unit test libc.test.src.sys.random.linux.getrandom_test.__NO_MISC_MATH_BASIC_OPS_OPT
[==========] Running 4 tests from 1 test suite.
[ RUN      ] LlvmLibcGetRandomTest.InvalidFlag
[       OK ] LlvmLibcGetRandomTest.InvalidFlag (4 us)
[ RUN      ] LlvmLibcGetRandomTest.InvalidBuffer
[       OK ] LlvmLibcGetRandomTest.InvalidBuffer (6 us)
[ RUN      ] LlvmLibcGetRandomTest.ReturnsSize
[       OK ] LlvmLibcGetRandomTest.ReturnsSize (17 us)
[ RUN      ] LlvmLibcGetRandomTest.CheckValue
[       OK ] LlvmLibcGetRandomTest.CheckValue (5 us)
Ran 4 tests.  PASS: 4  FAIL: 0
[940/1103] Running unit test libc.test.src.sys.random.linux.getrandom_test.__NO_FMA_OPT
[==========] Running 4 tests from 1 test suite.
[ RUN      ] LlvmLibcGetRandomTest.InvalidFlag

```

</details>

https://github.com/llvm/llvm-project/pull/118260