[PATCH] D45972: [ELF][MIPS] Fix calculation of GP relative relocations in case of relocatable output

[Simon Atanasyan via Phabricator via llvm-commits]

atanasyan added a comment.

> What bfd/gold do to solve this? I guess the same?

Yes.



================
Comment at: ELF/InputSection.cpp:393
+        if (Type == R_MIPS_GPREL32 || Type == R_MIPS_GPREL16 ||
+            R_MICROMIPS_GPREL16 || R_MICROMIPS_GPREL7_S2)
+          AddendAdjustment = Sec->getFile<ELFT>()->MipsGp0;
----------------
grimar wrote:
> Does not seem that test case covers all of these relocations?
Exactly. Moreover the patch contains a bug related to non-tested functionality. I will add more tests in the updated patch.


================
Comment at: ELF/InputSection.cpp:404
+            {R_ABS, Type, Rel.r_offset,
+             Target->getImplicitAddend(BufLoc, Type) + AddendAdjustment, &Sym});
       }
----------------
grimar wrote:
> I would probably make addend calculation a bit more explicit
> to avoid additional variable, something like:
> 
> ```
>   int64_t Addend = getAddend<ELFT>(Rel);
>   if (!RelTy::IsRela) {
>     const uint8_t *BufLoc = Sec->Data.begin() + Rel.r_offset;
>     Addend += Target->getImplicitAddend(BufLoc, Type);
>   }
> 
>   if (Config->EMachine == EM_MIPS && ...)
>     Addend += Sec->getFile<ELFT>()->MipsGp0;
> ...
> ```
OK


Repository:
  rLLD LLVM Linker

https://reviews.llvm.org/D45972