[lld] [lld] Merge GOT entries for symbols that have been ICFed (PR #131630)

[Peter Smith via llvm-commits]

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@@ -667,6 +667,20 @@ GotSection::GotSection(Ctx &ctx)
 void GotSection::addConstant(const Relocation &r) { relocations.push_back(r); }
 void GotSection::addEntry(const Symbol &sym) {
   assert(sym.auxIdx == ctx.symAux.size() - 1);
+  auto *d = dyn_cast<Defined>(&sym);
+  if (d && ctx.arg.icf != ICFLevel::None) {
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smithp35 wrote:

>From https://github.com/llvm/llvm-project/blob/main/lld/ELF/ICF.cpp#L269 I think that ICF wouldn't fold two sections if the symbols were preemptible.

The code now looks like it only merges entries if the definition is folded which should protect a preemptible symbol, however it looks like we could skip the insertion into gotEntries if the symbol was preemptible.
 

https://github.com/llvm/llvm-project/pull/131630