1 // RUN: %clang_cc1 -triple=x86_64-linux-gnu -emit-llvm -o - -std=c++17 %s | FileCheck %s --implicit-check-not=@_ZSt4move
2 
3 namespace std {
move(T & val)4   template<typename T> constexpr T &&move(T &val) { return static_cast<T&&>(val); }
5   template<typename T> constexpr T &&move_if_noexcept(T &val);
6   template<typename T> constexpr T &&forward(T &val);
7   template<typename T> constexpr const T &as_const(T &val);
8 
9   // Not the builtin.
10   template<typename T, typename U> T move(U source, U source_end, T dest);
11 }
12 
13 class T {};
14 extern "C" void take(T &&);
15 extern "C" void take_lval(const T &);
16 
17 T a;
18 
19 // Check emission of a constant-evaluated call.
20 // CHECK-DAG: @move_a = constant ptr @a
21 T &&move_a = std::move(a);
22 // CHECK-DAG: @move_if_noexcept_a = constant ptr @a
23 T &&move_if_noexcept_a = std::move_if_noexcept(a);
24 // CHECK-DAG: @forward_a = constant ptr @a
25 T &forward_a = std::forward<T&>(a);
26 
27 // Check emission of a non-constant call.
28 // CHECK-LABEL: define {{.*}} void @test
test(T & t)29 extern "C" void test(T &t) {
30   // CHECK: store ptr %{{.*}}, ptr %[[T_REF:[^,]*]]
31   // CHECK: %0 = load ptr, ptr %[[T_REF]]
32   // CHECK: call void @take(ptr {{.*}} %0)
33   take(std::move(t));
34   // CHECK: %1 = load ptr, ptr %[[T_REF]]
35   // CHECK: call void @take(ptr {{.*}} %1)
36   take(std::move_if_noexcept(t));
37   // CHECK: %2 = load ptr, ptr %[[T_REF]]
38   // CHECK: call void @take(ptr {{.*}} %2)
39   take(std::forward<T&&>(t));
40   // CHECK: %3 = load ptr, ptr %[[T_REF]]
41   // CHECK: call void @take_lval(ptr {{.*}} %3)
42   take_lval(std::as_const<T&&>(t));
43 
44   // CHECK: call {{.*}} @_ZSt4moveI1TS0_ET_T0_S2_S1_
45   std::move(t, t, t);
46 }
47 
48 // CHECK: declare {{.*}} @_ZSt4moveI1TS0_ET_T0_S2_S1_
49 
50 // Check that we instantiate and emit if the address is taken.
51 // CHECK-LABEL: define {{.*}} @use_address
use_address()52 extern "C" void *use_address() {
53   // CHECK: ret {{.*}} @_ZSt4moveIiEOT_RS0_
54   return (void*)&std::move<int>;
55 }
56 
57 // CHECK: define {{.*}} ptr @_ZSt4moveIiEOT_RS0_(ptr
58 
59 extern "C" void take_const_int_rref(const int &&);
60 // CHECK-LABEL: define {{.*}} @move_const_int(
move_const_int()61 extern "C" void move_const_int() {
62   // CHECK: store i32 5, ptr %[[N_ADDR:[^,]*]]
63   const int n = 5;
64   // CHECK: call {{.*}} @take_const_int_rref(ptr {{.*}} %[[N_ADDR]])
65   take_const_int_rref(std::move(n));
66 }
67