[clang] [CIR] Cleanup support for C functions (PR #136854)

[Andy Kaylor via cfe-commits]

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@@ -233,6 +233,19 @@ int f8(int *p) {
 // OGCG:   %[[P2:.*]] = load ptr, ptr %[[P_PTR]], align 8
 // OGCG:   %[[STAR_P:.*]] = load i32, ptr %[[P2]], align 4
 
+
+void f9() {}
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andykaylor wrote:

Since you added handling for required arguments, can you add a test that has a declaration with optional arguments and calls to that function with optional arguments emitted? I'd suggest a function with one required argument and two optional arguments and calls to that function with one, two, and three arguments provided. Perhaps also a test with zero required arguments and two optional arguments, called with zero, one, and two arguments.

https://github.com/llvm/llvm-project/pull/136854