[RelLookupTableConverter] Drop unnamed_addr to avoid generating GOTPCREL relocations (#142304)

Follow
https://github.com/llvm/llvm-project/pull/72584#issuecomment-2925759253,
the patch will drop the `unnamed_addr` attribute when generating
relative lookup tables. I'm not very confident about this patch, but it
does resolve https://github.com/rust-lang/rust/issues/140686,
https://github.com/rust-lang/rust/issues/141306 and
https://github.com/rust-lang/rust/issues/141737.

But I don't think this will result in worse problems.

> LLVM provides that the calculation of such a constant initializer will
not overflow at link time under the medium code model if x is an
unnamed_addr function. However, it does not provide this guarantee for a
constant initializer folded into a function body. This intrinsic can be
used to avoid the possibility of overflows when loading from such a
constant. ([‘llvm.load.relative’
Intrinsic](https://llvm.org/docs/LangRef.html#id2592))

This is my concern. I'm not sure how unnamed_addr provides this
guarantee, and I haven't found any test cases.
2 files changed
tree: 71add2d74e64bcd3750234a7bb07ba21464938b7
  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. libunwind/
  16. lld/
  17. lldb/
  18. llvm/
  19. llvm-libgcc/
  20. mlir/
  21. offload/
  22. openmp/
  23. polly/
  24. pstl/
  25. runtimes/
  26. third-party/
  27. utils/
  28. .clang-format
  29. .clang-format-ignore
  30. .clang-tidy
  31. .git-blame-ignore-revs
  32. .gitattributes
  33. .gitignore
  34. .mailmap
  35. CODE_OF_CONDUCT.md
  36. CONTRIBUTING.md
  37. LICENSE.TXT
  38. pyproject.toml
  39. README.md
  40. SECURITY.md
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