[clang] [clang][dataflow] Fix result object location for builtin `<=>`. (PR #88726)

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@@ -508,6 +508,11 @@ class ResultObjectVisitor : public RecursiveASTVisitor<ResultObjectVisitor> {
         isa<CXXStdInitializerListExpr>(E)) {
       return;
     }
+    if (auto *Op = dyn_cast<BinaryOperator>(E);
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martinboehme wrote:

I'm not sure.

*  The cases involving a `dyn_cast` need a cast anyway, as they access properties of the cast class. So if we introduced a switch, we would need a `case` _and_ a cast.

*  This leaves the `isa<>` cases above. IIUC, `isa<>` essentially compiles down to a test on `E->getStmtClass()`. So in terms of performance, replacing the `isa<>` calls above with a switch statement shouldn't make much of a difference. I think the `isa<>` version is more readable though.

So in all, I don't see a clear advantage, and I would prefer to keep this as-is.

https://github.com/llvm/llvm-project/pull/88726