[llvm] [PAC][CodeGen][ELF][AArch64] Support signed GOT (PR #96164)

[Tomas Matheson via llvm-commits]

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@@ -82,6 +83,25 @@ static bool ShouldSignWithBKey(const Function &F, const AArch64Subtarget &STI) {
   return Key == "b_key";
 }
 
+static bool hasELFSignedGOTHelper(const Function &F,
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tmatheson-arm wrote:

Please add a brief doc comment

https://github.com/llvm/llvm-project/pull/96164