[clang] [analyzer] Confidently inline final methods (PR #224070)

[Donát Nagy via cfe-commits]

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@@ -798,10 +798,18 @@ RuntimeDefinition CXXInstanceCall::getRuntimeDefinition() const {
   if (!MD->isVirtual())
     return AnyFunctionCall::getRuntimeDefinition();
 
+  // If the method is final or declared in a final class, we can inline it.
+  if (MD->hasAttr<FinalAttr>() || MD->getParent()->hasAttr<FinalAttr>())
+    return AnyFunctionCall::getRuntimeDefinition();
+
   auto [RD, CanBeSubClass] = getDeclForDynamicType();
   if (!RD || !RD->hasDefinition())
     return {};
 
+  // We can confidently inline a method called on an object with final type.
+  if (RD->hasAttr<FinalAttr>())
+    CanBeSubClass = false;
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NagyDonat wrote:

In the interesting case when the dynamic type of the object is not the static type, but a subclass of it, then that subclass must already be defined (to be able to specify that it is the subclass of another class), and I'm pretty sure that in this case the record declaration `RD` is the definition.  

https://github.com/llvm/llvm-project/pull/224070