[AArch64][PAC] Emit `!dbg` locations in `*_vfpthunk_` functions (#179688)

The usage of pointers to member functions with Pointer Authentication
requires generation of `*_vfpthunk_` functions. These thunk functions
can be later inlined and optimized by replacing the indirect call
instruction with a direct one and then inlining that function call.

In absence of `!dbg` metadata attached to the original call instruction,
such inlining ultimately results in an assertion "!dbg attachment points
at wrong subprogram for function" in the assertions-enabled builds. By
manually executing `opt` with `-verify-each` option on the LLVM IR
produced by the frontend, an actual issue can be observed: "inlinable
function call in a function with debug info must have a !dbg location"
after the replacement of indirect call instruction with the direct one
takes place.

This commit fixes the issue by attaching artificial `!dbg` locations to
the original call instruction (as well as most other instructions in
`*_vfpthunk_` function) the same way it is done for other
compiler-generated helper functions.

(cherry picked from commit 903acc2762d550d8f5934924aaf87b3527c63112)
2 files changed
tree: 694b25c5b81a80ad164bb2de2b48aee522d3eaaf
  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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