[llvm] [SLP] Make getSameOpcode support different instructions if they have same semantics. (PR #112181)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-cmake-x86_64-avx512-linux` running on `avx512-intel64` while building `llvm` at step 13 "test-suite".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/133/builds/8338

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

```
Step 13 (test-suite) failure: test (failure)
...
size..interp: 28 
size..note.ABI-tag: 32 
size..note.gnu.property: 32 
size..plt: 48 
size..rela.dyn: 192 
size..rela.plt: 48 
size..rodata: 91 
size..text: 2496 
**********
NOEXE: test-suite :: SingleSource/UnitTests/Vectorizer/gcc-loops.test (2455 of 2519)
******************** TEST 'test-suite :: SingleSource/UnitTests/Vectorizer/gcc-loops.test' FAILED ********************
Executable '/localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/test/sandbox/build/SingleSource/UnitTests/Vectorizer/gcc-loops' is missing
********************
PASS: test-suite :: SingleSource/UnitTests/Vector/AVX512VL/Vector-AVX512VL-i64gather_64.test (2456 of 2519)
********** TEST 'test-suite :: SingleSource/UnitTests/Vector/AVX512VL/Vector-AVX512VL-i64gather_64.test' RESULTS **********
compile_time: 0.0000 
exec_time: 0.0049 
hash: "9ef5ed4a2785bd740b64ef45c222af1e" 
link_time: 0.0242 
size: 23424 
size..bss: 5111824 
size..comment: 154 
size..data: 4 
size..data.rel.ro: 8 
size..dynamic: 496 
size..dynstr: 153 
size..dynsym: 168 
size..eh_frame: 316 
size..eh_frame_hdr: 84 
size..fini: 13 
size..fini_array: 8 
size..gnu.build.attributes: 5004 
size..gnu.hash: 28 
size..gnu.version: 14 
size..gnu.version_r: 48 
size..got: 40 
size..got.plt: 40 
size..init: 27 
size..init_array: 8 
size..interp: 28 
size..note.ABI-tag: 32 
size..note.gnu.property: 32 
size..plt: 48 
size..rela.dyn: 192 
size..rela.plt: 48 
size..rodata: 95 
size..text: 2222 
**********
PASS: test-suite :: SingleSource/UnitTests/Vector/Vector-constpool.test (2457 of 2519)

```

</details>

https://github.com/llvm/llvm-project/pull/112181