[JITLink][RISCV] Only generate PLT entries for external symbols

R_RISCV_CALL has been deprecated. [1] Both GCC and LLVM seem to not
generate it anymore and always use R_RISCV_CALL_PLT (even for calls that
do not need a PLT entry). Generating PLT entries based on relocation
type is not recommended and a better heuristic is to only generate them
when the target symbol is preemptable [2]. This patch implements this by
only generating PLT entries for undefined symbols.

[1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/340
[2] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/issues/98

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D149525
2 files changed
tree: bb78f040cb031fa52a3684a22a97423505d23c17
  1. .github/
  2. bolt/
  3. clang/
  4. clang-tools-extra/
  5. cmake/
  6. compiler-rt/
  7. cross-project-tests/
  8. flang/
  9. libc/
  10. libclc/
  11. libcxx/
  12. libcxxabi/
  13. libunwind/
  14. lld/
  15. lldb/
  16. llvm/
  17. llvm-libgcc/
  18. mlir/
  19. openmp/
  20. polly/
  21. pstl/
  22. runtimes/
  23. third-party/
  24. utils/
  25. .arcconfig
  26. .arclint
  27. .clang-format
  28. .clang-tidy
  29. .git-blame-ignore-revs
  30. .gitignore
  31. .mailmap
  32. CONTRIBUTING.md
  33. LICENSE.TXT
  34. README.md
  35. SECURITY.md
README.md

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