[llvm-branch-commits] [clang] [clang] Implement pointer authentication for C++ virtual functions, v-tables, and VTTs (PR #94056)

[Anton Korobeynikov via llvm-branch-commits]

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@@ -2456,10 +2456,20 @@ class CodeGenFunction : public CodeGenTypeCache {
 
   void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
 
+  // VTableTrapMode - whether we guarantee that loading the
+  // vtable is guaranteed to trap on authentication failure,
+  // even if the resulting vtable pointer is unused.
+  enum class VTableAuthMode {
+    Authenticate,
+    MustTrap,
+    UnsafeUbsanStrip // Should only be used for Vptr UBSan check
+  };
   /// GetVTablePtr - Return the Value of the vtable pointer member pointed
   /// to by This.
-  llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
-                            const CXXRecordDecl *VTableClass);
+  llvm::Value *
+  GetVTablePtr(Address This, llvm::Type *VTableTy,
+               const CXXRecordDecl *VTableClass,
+               VTableAuthMode authMode = VTableAuthMode::Authenticate);
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asl wrote:

```suggestion
               VTableAuthMode AuthMode = VTableAuthMode::Authenticate);
```

https://github.com/llvm/llvm-project/pull/94056