1// RUN: %clang_cc1 -triple i686-linux-gnu -emit-llvm %s -o - | FileCheck %s --check-prefix=CHECK-O0
2// RUN: %clang_cc1 -triple i686-linux-gnu -emit-llvm %s -O1 -o - | FileCheck %s
3
4// Check that we add an llvm.invariant.start to mark when a global becomes
5// read-only. If globalopt can fold the initializer, it will then mark the
6// variable as constant.
7
8// Do not produce markers at -O0.
9// CHECK-O0-NOT: llvm.invariant.start
10
11struct A {
12  A();
13  int n;
14};
15
16// CHECK: @a = global {{.*}} zeroinitializer
17extern const A a = A();
18
19struct B {
20  B();
21  mutable int n;
22};
23
24// CHECK: @b = global {{.*}} zeroinitializer
25extern const B b = B();
26
27struct C {
28  C();
29  ~C();
30  int n;
31};
32
33// CHECK: @c = global {{.*}} zeroinitializer
34extern const C c = C();
35
36int f();
37// CHECK: @d = global i32 0
38extern const int d = f();
39
40void e() {
41  static const A a = A();
42}
43
44// CHECK: call void @_ZN1AC1Ev({{.*}}* @a)
45// CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @a to i8*))
46
47// CHECK: call void @_ZN1BC1Ev({{.*}}* @b)
48// CHECK-NOT: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @b to i8*))
49
50// CHECK: call void @_ZN1CC1Ev({{.*}}* @c)
51// CHECK-NOT: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @c to i8*))
52
53// CHECK: call i32 @_Z1fv(
54// CHECK: store {{.*}}, i32* @d
55// CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @d to i8*))
56
57// CHECK-LABEL: define void @_Z1ev(
58// CHECK: call void @_ZN1AC1Ev(%struct.A* @_ZZ1evE1a)
59// CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @_ZZ1evE1a to i8*))
60// CHECK-NOT: llvm.invariant.end
61