1 // For MSVC ABI compatibility, all structures returned by value using the
2 // thiscall calling convention must use the hidden parameter.
3 //
4 // RUN: %clang_cc1 -triple i386-PC-Win32 %s -fms-compatibility -emit-llvm -o - | FileCheck %s
5 
6 // This structure would normally be returned via EAX
7 struct S {
8   int i;
9 };
10 
11 // This structure would normally be returned via EAX/EDX
12 struct M {
13   int i;
14   int j;
15 };
16 
17 class C {
18 public:
19   C() {}
20 
21   struct S __attribute__((thiscall)) Small() const {
22     struct S s = { 0 };
23     return s;
24   }
25 
26   struct M __attribute__((thiscall)) Medium() const {
27     struct M m = { 0 };
28     return m;
29   }
30 };
31 
32 // CHECK-LABEL: define void @_Z4testv()
33 void test( void ) {
34 // CHECK: call void @_ZN1CC1Ev(%class.C* [[C:%.+]])
35   C c;
36 
37 // CHECK: call x86_thiscallcc void @_ZNK1C5SmallEv(%struct.S* sret %{{.+}}, %class.C* [[C]])
38   (void)c.Small();
39 // CHECK: call x86_thiscallcc void @_ZNK1C6MediumEv(%struct.M* sret %{{.+}}, %class.C* [[C]])
40   (void)c.Medium();
41 }
42