tree ac10003678d23218d10ba40cfdbec3735e1047da
parent 5d007bf9de91d0592bdcffca80d68f6bae2bb255
author Fangrui Song <i@maskray.me> 1636739251 -0800
committer Copybara-Service <copybara-worker@google.com> 1636739475 -0800

[ELF] Make --no-relax disable R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX GOT optimization

This brings back the original version of D81359.
I have found several use cases now.

* Unlike GNU ld, LLD's relocation processing is one pass. If we decide to
  optimize(relax) R_X86_64_{,REX_}GOTPCRELX, we will suppress GOT generation and
  cannot undo the decision later. Optimizing R_X86_64_REX_GOTPCRELX can usually
  make it easy to hit `relocation R_X86_64_REX_GOTPCRELX out of range` because
  the distance to GOT is usually shorter. Without --no-relax, the user has to
  recompile with `-Wa,-mrelax-relocations=no`.
* The option would help during my investigationg of the root cause of https://git.kernel.org/linus/09e43968db40c33a73e9ddbfd937f46d5c334924
* There is need for relaxation for AArch64 & RISC-V. Implementing this for
  x86-64 improves consistency with little target-specific cost (two-line
  X86_64.cpp change).

Reviewed By: alexander-shaposhnikov

Differential Revision: https://reviews.llvm.org/D113615

GitOrigin-RevId: a05384dc8930cbe967def7c5c4113740838e8fd0