[GlobalOpt] Cache whether CC is changeable (#71381)

The hasAddressTaken() call in hasOnlyColdCalls() has quadratic
complexity if there are many cold calls to a function: We're going to
visit each call of the function, and then for each of them iterate all
the users of the function.

We've recently encountered a case where GlobalOpt spends more than an
hour in these hasAddressTaken() checks when full LTO is used.

Avoid this by moving the hasAddressTaken() check into hasChangeableCC()
and caching its result, so it is only computed once per function.

(cherry picked from commit e360a16fee2dc3cb632ace556fb715832f488a90)
1 file changed
tree: db6139e61de6b479437c4f0e3fc883b27b810a61
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. libc/
  11. libclc/
  12. libcxx/
  13. libcxxabi/
  14. libunwind/
  15. lld/
  16. lldb/
  17. llvm/
  18. llvm-libgcc/
  19. mlir/
  20. openmp/
  21. polly/
  22. pstl/
  23. runtimes/
  24. third-party/
  25. utils/
  26. .arcconfig
  27. .arclint
  28. .clang-format
  29. .clang-tidy
  30. .git-blame-ignore-revs
  31. .gitignore
  32. .mailmap
  33. CONTRIBUTING.md
  34. LICENSE.TXT
  35. README.md
  36. SECURITY.md
README.md

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