[llvm] [PAC][CodeGen][ELF][AArch64] Support signed GOT (PR #113811)

[Fangrui Song via llvm-commits]

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@@ -72,6 +72,18 @@ static bool ShouldSignWithBKey(const Function &F, const AArch64Subtarget &STI) {
   return Key == "b_key";
 }
 
+static bool HasELFSignedGOTHelper(const Function &F,
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MaskRay wrote:

`hasELF...` (fix style when adding new functions)

https://github.com/llvm/llvm-project/pull/113811