clang/test/CodeGenCXX/microsoft-abi-cdecl-method-sret.cpp

   1 // RUN: %clang_cc1 -triple i386-pc-win32 -emit-llvm %s -o - | FileCheck %s
   2
   3 // PR15768
   4
   5 // A trivial 20 byte struct is returned indirectly and taken as byval.
   6 struct S {
   7   S();
   8   int a, b, c, d, e;
   9 };
  10
  11 struct C {
  12   S variadic_sret(const char *f, ...);
  13   S __cdecl cdecl_sret();
  14   S __cdecl byval_and_sret(S a);
  15   int c;
  16 };
  17
  18 S C::variadic_sret(const char *f, ...) { return S(); }
  19 S C::cdecl_sret() { return S(); }
  20 S C::byval_and_sret(S a) { return S(); }
  21
  22 // CHECK: define dso_local void @"?variadic_sret@C@@QAA?AUS@@PBDZZ"(%struct.C* {{[^,]*}} %this, %struct.S* noalias sret(%struct.S) align 4 %agg.result, i8* noundef %f, ...)
  23 // CHECK: define dso_local void @"?cdecl_sret@C@@QAA?AUS@@XZ"(%struct.C* {{[^,]*}} %this, %struct.S* noalias sret(%struct.S) align 4 %agg.result)
  24 // CHECK: define dso_local void @"?byval_and_sret@C@@QAA?AUS@@U2@@Z"(%struct.C* {{[^,]*}} %this, %struct.S* noalias sret(%struct.S) align 4 %agg.result, %struct.S* noundef byval(%struct.S) align 4 %a)
  25
  26 int main() {
  27   C c;
  28   c.variadic_sret("asdf");
  29   c.cdecl_sret();
  30   c.byval_and_sret(S());
  31 }
  32 // CHECK-LABEL: define dso_local noundef i32 @main()
  33 // CHECK: call void {{.*}} @"?variadic_sret@C@@QAA?AUS@@PBDZZ"
  34 // CHECK: call void @"?cdecl_sret@C@@QAA?AUS@@XZ"
  35 // CHECK: call void @"?byval_and_sret@C@@QAA?AUS@@U2@@Z"
  36
  37 // __fastcall has similar issues.
  38 struct A {
  39   S __fastcall f(int x);
  40 };
  41 S A::f(int x) {
  42   return S();
  43 }
  44 // CHECK-LABEL: define dso_local x86_fastcallcc void @"?f@A@@QAI?AUS@@H@Z"(%struct.A* inreg noundef nonnull align 1 dereferenceable(1) %this, %struct.S* inreg noalias sret(%struct.S) align 4 %agg.result, i32 noundef %x)