xref: /aosp_15_r20/external/clang/test/CodeGenCXX/init-invariant.cpp (revision 67e74705e28f6214e480b399dd47ea732279e315)
1*67e74705SXin Li // RUN: %clang_cc1 -triple i686-linux-gnu -emit-llvm %s -o - | FileCheck %s --check-prefix=CHECK-O0
2*67e74705SXin Li // RUN: %clang_cc1 -triple i686-linux-gnu -emit-llvm %s -O1 -o - | FileCheck %s
3*67e74705SXin Li 
4*67e74705SXin Li // Check that we add an llvm.invariant.start to mark when a global becomes
5*67e74705SXin Li // read-only. If globalopt can fold the initializer, it will then mark the
6*67e74705SXin Li // variable as constant.
7*67e74705SXin Li 
8*67e74705SXin Li // Do not produce markers at -O0.
9*67e74705SXin Li // CHECK-O0-NOT: llvm.invariant.start
10*67e74705SXin Li 
11*67e74705SXin Li struct A {
12*67e74705SXin Li   A();
13*67e74705SXin Li   int n;
14*67e74705SXin Li };
15*67e74705SXin Li 
16*67e74705SXin Li // CHECK: @a = global {{.*}} zeroinitializer
17*67e74705SXin Li extern const A a = A();
18*67e74705SXin Li 
19*67e74705SXin Li struct B {
20*67e74705SXin Li   B();
21*67e74705SXin Li   mutable int n;
22*67e74705SXin Li };
23*67e74705SXin Li 
24*67e74705SXin Li // CHECK: @b = global {{.*}} zeroinitializer
25*67e74705SXin Li extern const B b = B();
26*67e74705SXin Li 
27*67e74705SXin Li struct C {
28*67e74705SXin Li   C();
29*67e74705SXin Li   ~C();
30*67e74705SXin Li   int n;
31*67e74705SXin Li };
32*67e74705SXin Li 
33*67e74705SXin Li // CHECK: @c = global {{.*}} zeroinitializer
34*67e74705SXin Li extern const C c = C();
35*67e74705SXin Li 
36*67e74705SXin Li int f();
37*67e74705SXin Li // CHECK: @d = global i32 0
38*67e74705SXin Li extern const int d = f();
39*67e74705SXin Li 
e()40*67e74705SXin Li void e() {
41*67e74705SXin Li   static const A a = A();
42*67e74705SXin Li }
43*67e74705SXin Li 
44*67e74705SXin Li // CHECK: call void @_ZN1AC1Ev({{.*}}* nonnull @a)
45*67e74705SXin Li // CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @a to i8*))
46*67e74705SXin Li 
47*67e74705SXin Li // CHECK: call void @_ZN1BC1Ev({{.*}}* nonnull @b)
48*67e74705SXin Li // CHECK-NOT: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @b to i8*))
49*67e74705SXin Li 
50*67e74705SXin Li // CHECK: call void @_ZN1CC1Ev({{.*}}* nonnull @c)
51*67e74705SXin Li // CHECK-NOT: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @c to i8*))
52*67e74705SXin Li 
53*67e74705SXin Li // CHECK: call i32 @_Z1fv(
54*67e74705SXin Li // CHECK: store {{.*}}, i32* @d
55*67e74705SXin Li // CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* bitcast ({{.*}} @d to i8*))
56*67e74705SXin Li 
57*67e74705SXin Li // CHECK-LABEL: define void @_Z1ev(
58*67e74705SXin Li // CHECK: call void @_ZN1AC1Ev(%struct.A* nonnull @_ZZ1evE1a)
59*67e74705SXin Li // CHECK: call {{.*}}@llvm.invariant.start(i64 4, i8* {{.*}}bitcast ({{.*}} @_ZZ1evE1a to i8*))
60*67e74705SXin Li // CHECK-NOT: llvm.invariant.end
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