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

[Peter Collingbourne 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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pcc wrote:

Doesn't this also need to check that the symbol is non-preemptible? We don't want to merge GOT entries for preemptible symbols, as that could break preemption semantics.

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