[clang] [analyzer] Fix assertion failure in `CXXInstanceCall::getCXXThisVal` (PR #70837)

[via cfe-commits]

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@@ -30,3 +30,24 @@ void test(int i) {
   clang_analyzer_dump(g4);
   // expected-warning at -1 {{&i [as 64 bit integer]}}
 }
+
+struct A {
+  int n;
+  void set(int x) {
+    n = x;
+  }
+};
+using ptr_size = decltype(sizeof(void *));
+void gh_69922(ptr_size p) {
+  // expected-warning-re at +1 {{(reg_${{[0-9]+}}<ptr_size p>) & 1U}}
+  clang_analyzer_dump(__builtin_bit_cast(A*, p & 1));
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DonatNagyE wrote:

What is the role of the `&` operator here? Is it just an arbitrary numerical operation that's not handled by the analyzer?

(No action needed, I'm just curious.) 

https://github.com/llvm/llvm-project/pull/70837