[LoopVectorize] Clear stale CycleAnalysis where BlockFrequencyInfo is requested (#220173)

The cost model requests BlockFrequencyInfo lazily, after runImpl has
simplified loops and possibly vectorized some of them. A CycleInfo
cached by an earlier pass then describes the original CFG, and
BlockFrequencyInfo asserts `Resolved >= Pred && "unhandled irreducible control flow"'.

Clear it at the request site, gated on the CFGChanged flag the pass
already uses to decide whether CFGAnalyses are preserved. This covers
loop simplification, which runs before the first loop is processed.

Fixes #218392, exposed by BlockFrequencyInfo migrating to CycleAnalysis.

Aided by Opus 5
3 files changed
tree: 48fae44a7a3fa6f6a8859fcefcb96756055d6105
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. flang-rt/
  11. libc/
  12. libclc/
  13. libcxx/
  14. libcxxabi/
  15. libsycl/
  16. libunwind/
  17. lld/
  18. lldb/
  19. llvm/
  20. llvm-libgcc/
  21. mlir/
  22. offload/
  23. openmp/
  24. orc-rt/
  25. polly/
  26. runtimes/
  27. third-party/
  28. utils/
  29. .clang-format
  30. .clang-format-ignore
  31. .clang-tidy
  32. .git-blame-ignore-revs
  33. .gitattributes
  34. .gitignore
  35. .mailmap
  36. CODE_OF_CONDUCT.md
  37. CONTRIBUTING.md
  38. LICENSE.TXT
  39. pyproject.toml
  40. README.md
  41. SECURITY.md
README.md

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