1 files changed, 100 insertions, 0 deletions
diff --git a/clang/test/CodeGen/tbaa-union.cpp b/clang/test/CodeGen/tbaa-union.cpp
new file mode 100644
index 00000000000..066d7c9e9ff
--- /dev/null
+++ b/clang/test/CodeGen/tbaa-union.cpp
@@ -0,0 +1,100 @@
+// RUN: %clang_cc1 -triple x86_64-linux -O1 -disable-llvm-passes %s -emit-llvm -o - | FileCheck %s
+//
+// Check that we generate correct TBAA information for accesses to union
+// members.
+
+struct X {
+  int a, b;
+  int arr[3];
+  int c, d;
+};
+
+union U {
+  int i;
+  X x;
+  int j;
+};
+
+struct S {
+  U u, v;
+};
+
+union N {
+  int i;
+  S s;
+  int j;
+};
+
+struct R {
+  N n, m;
+};
+
+int f1(U *p) {
+// CHECK-LABEL: _Z2f1P1U
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_U_j:!.*]]
+  return p->j;
+}
+
+int f2(S *p) {
+// CHECK-LABEL: _Z2f2P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_u_i:!.*]]
+  return p->u.i;
+}
+
+int f3(S *p) {
+// CHECK-LABEL: _Z2f3P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_v_j:!.*]]
+  return p->v.j;
+}
+
+int f4(S *p) {
+// CHECK-LABEL: _Z2f4P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_u_x_b:!.*]]
+  return p->u.x.b;
+}
+
+int f5(S *p) {
+// CHECK-LABEL: _Z2f5P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_v_x_b:!.*]]
+  return p->v.x.b;
+}
+
+int f6(S *p) {
+// CHECK-LABEL: _Z2f6P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_u_x_arr:!.*]]
+  return p->u.x.arr[1];
+}
+
+int f7(S *p) {
+// CHECK-LABEL: _Z2f7P1S
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_S_v_x_arr:!.*]]
+  return p->v.x.arr[1];
+}
+
+int f8(N *p) {
+// CHECK-LABEL: _Z2f8P1N
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_N_s_v_x_c:!.*]]
+  return p->s.v.x.c;
+}
+
+int f9(R *p) {
+// CHECK-LABEL: _Z2f9P1R
+// CHECK: load i32, i32* {{.*}}, !tbaa [[TAG_R_m_s_v_x_c:!.*]]
+  return p->m.s.v.x.c;
+}
+
+// CHECK-DAG: [[TAG_U_j]] = !{[[TYPE_U:!.*]], [[TYPE_union_member:!.*]], i64 0}
+// CHECK-DAG: [[TAG_S_u_i]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TAG_S_u_x_b]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TAG_S_u_x_arr]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TAG_S_v_j]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 28}
+// CHECK-DAG: [[TAG_S_v_x_b]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 28}
+// CHECK-DAG: [[TAG_S_v_x_arr]] = !{[[TYPE_S:!.*]], [[TYPE_union_member]], i64 28}
+// CHECK-DAG: [[TAG_N_s_v_x_c]] = !{[[TYPE_N:!.*]], [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TAG_R_m_s_v_x_c]] = !{[[TYPE_R:!.*]], [[TYPE_union_member]], i64 56}
+// CHECK-DAG: [[TYPE_U]] = !{!"_ZTS1U", [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TYPE_S]] = !{!"_ZTS1S", [[TYPE_U]], i64 0, [[TYPE_U]], i64 28}
+// CHECK-DAG: [[TYPE_N]] = !{!"_ZTS1N", [[TYPE_union_member]], i64 0}
+// CHECK-DAG: [[TYPE_R]] = !{!"_ZTS1R", [[TYPE_N]], i64 0, [[TYPE_N]], i64 56}
+// CHECK-DAG: [[TYPE_union_member]] = !{!"union member", [[TYPE_char:!.*]], i64 0}
+// CHECK-DAG: [[TYPE_char]] = !{!"omnipotent char", {{.*}}, i64 0}