[llvm] [BOLT][binary-analysis] Add initial pac-ret gadget scanner (PR #122304)

[Kristof Beyls via llvm-commits]

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@@ -550,6 +550,22 @@ class MCPlusBuilder {
     return Analysis->isReturn(Inst);
   }
 
+  virtual MCPhysReg getAuthenticatedReg(const MCInst &Inst) const {
+    llvm_unreachable("not implemented");
+    return false;
+  }
+
+  virtual bool isAuthenticationOfReg(const MCInst &Inst,
+                                     const unsigned RegAuthenticated) const {
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kbeyls wrote:

Thanks for the suggested name change on the function parameter, makes sense.

https://github.com/llvm/llvm-project/pull/122304