[clang] [CIR] Support ComplexType in CallExpr args (PR #156236)

[Andy Kaylor via cfe-commits]

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@@ -909,3 +909,46 @@ void foo33(__builtin_va_list a) {
 // OGCG:  %[[B_IMAG_PTR:.*]] = getelementptr inbounds nuw { float, float }, ptr %[[B_ADDR]], i32 0, i32 1
 // OGCG:  store float %[[RESULT_REAL]], ptr %[[B_REAL_PTR]], align 4
 // OGCG:  store float %[[RESULT_IMAG]], ptr %[[B_IMAG_PTR]], align 4
+
+void foo34(float _Complex a) {}
+
+// CIR: %[[A_ADDR:.*]] = cir.alloca !cir.complex<!cir.float>, !cir.ptr<!cir.complex<!cir.float>>, ["a", init]
+// CIR: cir.store %{{.*}}, %[[A_ADDR]] : !cir.complex<!cir.float>, !cir.ptr<!cir.complex<!cir.float>>
+
+// LLVM: %[[A_ADDR:.*]] = alloca { float, float }, i64 1, align 4
+// LLVM: store { float, float } %{{.*}}, ptr %[[A_ADDR]], align 4
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andykaylor wrote:

Without calling convention lowering, any complex arguments are likely to be wrong. I'm not sure there's any value in lowering such arguments to LLVM IR before we've handled the calling convention part. Is there any way we can detect that and emit an error?

https://github.com/llvm/llvm-project/pull/156236