[lld] [llvm] [LoongArch] Use R_LARCH_ALIGN with section symbol (PR #84741)

[Fangrui Song via llvm-commits]

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@@ -462,7 +462,11 @@ void InputSection::copyRelocations(uint8_t *buf,
         addend += sec->getFile<ELFT>()->mipsGp0;
       }
 
-      if (RelTy::IsRela)
+      if (config->emachine == EM_LOONGARCH && type == R_LARCH_ALIGN)
+        // LoongArch psABI v2.30, the R_LARCH_ALIGN requires symbol index.
+        // If it use the section symbol, the addend should not be changed.
+        p->r_addend = addend;
+      else if (RelTy::IsRela)
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MaskRay wrote:

I am more convinced that the generic function should be moved to Arch/ as I did for `relocateAlloc`. You might not be interested in doing such generic improvement. I'll investigate it.

https://github.com/llvm/llvm-project/pull/84741