[all-commits] [llvm/llvm-project] 26ee89: [JITLink][RISCV] Only generate PLT entries for ext...

[Job Noorman via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 26ee8947702d79ce2cab8e577f713685a5ca4a55
      https://github.com/llvm/llvm-project/commit/26ee8947702d79ce2cab8e577f713685a5ca4a55
  Author: Job Noorman <jnoorman at igalia.com>
  Date:   2023-05-08 (Mon, 08 May 2023)

  Changed paths:
    M llvm/lib/ExecutionEngine/JITLink/ELF_riscv.cpp
    M llvm/test/ExecutionEngine/JITLink/RISCV/ELF_pc_indirect.s

  Log Message:
  -----------
  [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