[clang] [llvm] [PAC][ELF][AArch64] Support signed personality function pointer (PR #119361)

[Fangrui Song via llvm-commits]

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@@ -59,3 +61,13 @@ MachineModuleInfoImpl::ExprStubListTy MachineModuleInfoImpl::getSortedExprStubs(
   ExprStubs.clear();
   return List;
 }
+
+MachineModuleInfoELF::MachineModuleInfoELF(const MachineModuleInfo &MMI) {
+  const Module *M = MMI.getModule();
+  const auto *Flag = mdconst::extract_or_null<ConstantInt>(
+      M->getModuleFlag("ptrauth-sign-personality"));
+  if (Flag && Flag->getZExtValue() == 1)
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MaskRay wrote:

`HasSignedPersonality = Flag && ... == 1`

https://github.com/llvm/llvm-project/pull/119361