[AA] No synchronization effects for never-escaping identified local (#193939)

Fences and other synchronizing operations (such as atomic accesses
stronger than monotonic) are modelled as reading and writing all memory,
in order to enforce their implied ordering constraints.

Currently, this happens even for identified function locals that do not
escape. This patch excludes those objects.

Notably, we can *not* reason based on captures-before here, because the
synchronizing operation still has an effect even if the object only
escapes *later*.

The hope here is that with this restriction in place, it may be viable
to respect potential synchronization inside non-nosync function calls.
7 files changed
tree: 381135cdface3a09aa7737b7c52e8d01bdd6a599
  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

The LLVM Compiler Infrastructure

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