[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 guess the `isa` calls were what we really jumped out since they amount to N calls and tests on `getStmtClass` rather than one and a jump. But, readability wins over performance here.

I see what you mean -- yes, the switch statement would likely perform better here, but I agree that readability is more important than this micro-optimization.

> But, I do wonder about readability win from converting to a switch because it will directly express which cases are covered in this function, rather than leaving it implicit in a series of `if`s. FWIW.

I still have my doubts whether this will really be more readable, but I'll explore this. I'd prefer to do this as a separate PR though, as I'd like to keep this PR focused on the fix I'm making here. (If I convert the function to a switch statement in this PR, those code changes would drown out the few lines of actual behavioral change I'm making.)

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