[libunwind] [llvm] [MC][AArch64] Add .cfi_llvm_set_ra_sign_state for PAuth_LR (PR #205442)

[Jack Styles via cfe-commits]

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@@ -1330,6 +1330,9 @@ void MCCFIInstruction::replaceRegister(unsigned FromReg, unsigned ToReg) {
         ReplaceReg(F.Register);
         ReplaceReg(F.SpillRegister);
         ReplaceReg(F.MaskRegister);
+      },
+      [](LLVMSetRAStateFields &) {
+        assert(false && ".cfi_llvm_set_ra_state does not have registers");
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Stylie777 wrote:

If we are intending to always error when we reach here, llvm_unreachable would be better.

https://github.com/llvm/llvm-project/pull/205442