[llvm] CodeGen: More accurate mayAlias for instructions with multiple MMOs (PR #166211)

[Nicolai Hähnle via llvm-commits]

nhaehnle wrote:

The Windows CI reports a failure, but the logs look completely clean except for this error that seems to originate from the CI infra itself:
```
2025-11-06T16:56:57.0555141Z + python C:/_work/llvm-project/llvm-project/.ci/generate_test_report_github.py 0 C:/_work/llvm-project/llvm-project/build/test-results.7hrcixpi.xml C:/_work/llvm-project/llvm-project/build/test-results._337lz6b.xml C:/_work/llvm-project/llvm-project/build/test-results.bkrbjuib.xml C:/_work/llvm-project/llvm-project/build/test-results.g3dbdeym.xml C:/_work/llvm-project/llvm-project/build/test-results.ll76ye1t.xml C:/_work/llvm-project/llvm-project/build/test-results.y4zoj7fv.xml C:/_work/llvm-project/llvm-project/ninja.log
2025-11-06T16:56:57.1272333Z Traceback (most recent call last):
2025-11-06T16:56:57.1272859Z   File "C:\_work\llvm-project\llvm-project\.ci\generate_test_report_github.py", line 9, in <module>
2025-11-06T16:56:57.1274006Z     import generate_test_report_lib
2025-11-06T16:56:57.1274366Z   File "C:\_work\llvm-project\llvm-project\.ci\generate_test_report_lib.py", line 13, in <module>
2025-11-06T16:56:57.1275439Z     class FailureExplanation(TypedDict):
2025-11-06T16:56:57.1275849Z   File "C:\_work\llvm-project\llvm-project\.ci\generate_test_report_lib.py", line 16, in FailureExplanation
2025-11-06T16:56:57.1276567Z     reason: str | None
2025-11-06T16:56:57.1276844Z TypeError: unsupported operand type(s) for |: 'type' and 'NoneType'
2025-11-06T16:56:57.1404087Z ##[error]Process completed with exit code 1.
```

https://github.com/llvm/llvm-project/pull/166211