[clang] [CIR] Upstream ComplexType builtin_complex (PR #144225)

[Amr Hesham via cfe-commits]

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@@ -176,3 +176,27 @@ void foo7() {
 // OGCG: store float %[[TMP_A]], ptr %[[C_REAL_PTR]], align 4
 // OGCG: store float 2.000000e+00, ptr %[[C_IMAG_PTR]], align 4
 
+void foo9(double r, double i) {
+  double _Complex c = __builtin_complex(r, i);
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AmrDeveloper wrote:

- `builtin_complex` accepts only floating points

- Both arguments can be expressed, but I need to implement the rest of the visitors in `ComplexExprEmitter`


https://github.com/llvm/llvm-project/pull/144225