[llvm] [AArch64][PAC] Lower ptrauth constants in code for MachO. (PR #97665)

[Ahmed Bougacha via llvm-commits]

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@@ -36,6 +36,11 @@ class MachineModuleInfoMachO : public MachineModuleInfoImpl {
   /// bit is true if this GV is external.
   DenseMap<MCSymbol *, StubValueTy> ThreadLocalGVStubs;
 
+  /// Darwin '$auth_ptr' stubs.  The key is the stub symbol, like
+  /// "Lfoo$addend$auth_ptr$ib$12".  The value is the MCExpr representing that
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ahmedbougacha wrote:

Right, I don't think we'll ever need the addend support here, I'm keeping it downstream for some other use-cases.

I should mention we're also missing the address-diversity support here, and that one we'll likely want to add here in the future, at least for MachO;  we'll see then whether it's needed for ELF, given the broader support for auth GOT relocations that MachO doesn't expose.

https://github.com/llvm/llvm-project/pull/97665