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 -O0 -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: 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
