[profcheck] Fix profle metatdata propagation for Large Integer operations (#175862)

This PR improves the propagation of profile metadata within the
ExpandIRInsts pass. When lowering large integer division operations, the
pass now ensures that branch weights are correctly attached to the
generated control flow, preventing the loss of profile data during IR
expansion.

This PR improves signed and unsigned division/remainder for non-native
bit widths (e.g., `sdiv/udiv i129`, `srem/urem i129`) and implemented
Heuristic-Based Branch Weights labeling using established heuristics for
edge cases e.g., `Division-by-zero guards` and `Magnitude comparisons
between dividends and divisors`.

It also adds detailed comments within the expansion logic to explain the
rationale behind specific branch weight choices and the underlying
mathematical invariants.

Please refer to the implementation details in the source code for the
specific branch weight values and the logic governing their application.

Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
12 files changed
tree: 5f64b13e5b20301946bfd1b2e64948ca707640c6
  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
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