1 files changed, 47 insertions, 0 deletions
diff --git a/test/CodeGen/named_reg_global.c b/test/CodeGen/named_reg_global.c
new file mode 100644
index 000000000000..8117daef615c
--- /dev/null
+++ b/test/CodeGen/named_reg_global.c
@@ -0,0 +1,47 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple arm64-linux-gnu -S -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple armv7-linux-gnu -S -emit-llvm %s -o - | FileCheck %s
+
+// CHECK-NOT: @sp = common global
+register unsigned long current_stack_pointer asm("sp");
+struct p4_Thread {
+  struct {
+    int len;
+  } word;
+};
+// Testing pointer types as well
+register struct p4_Thread *p4TH asm("sp");
+
+// CHECK: define{{.*}} i[[bits:[0-9]+]] @get_stack_pointer_addr()
+// CHECK: [[ret:%[0-9]+]] = call i[[bits]] @llvm.read_register.i[[bits]](metadata !0)
+// CHECK: ret i[[bits]] [[ret]]
+unsigned long get_stack_pointer_addr() {
+  return current_stack_pointer;
+}
+// CHECK: declare{{.*}} i[[bits]] @llvm.read_register.i[[bits]](metadata)
+
+// CHECK: define{{.*}} void @set_stack_pointer_addr(i[[bits]] %addr) #0 {
+// CHECK: [[sto:%[0-9]+]] = load i[[bits]]* %
+// CHECK: call void @llvm.write_register.i[[bits]](metadata !0, i[[bits]] [[sto]])
+// CHECK: ret void
+void set_stack_pointer_addr(unsigned long addr) {
+  current_stack_pointer = addr;
+}
+// CHECK: declare{{.*}} void @llvm.write_register.i[[bits]](metadata, i[[bits]])
+
+// CHECK: define {{.*}}@fn1
+int fn1() {
+  return (*p4TH).word.len;
+}
+// CHECK: %[[regr:[0-9]+]] = call i[[bits]] @llvm.read_register.i[[bits]](metadata !0)
+// CHECK: inttoptr i[[bits]] %[[regr]] to %struct.p4_Thread*
+
+// CHECK: define {{.*}}@fn2
+void fn2(struct p4_Thread *val) {
+  p4TH = val;
+}
+// CHECK: %[[regw:[0-9]+]] = ptrtoint %struct.p4_Thread* %{{.*}} to i[[bits]]
+// CHECK: call void @llvm.write_register.i[[bits]](metadata !0, i[[bits]] %[[regw]])
+
+// CHECK: !llvm.named.register.sp = !{!0}
+// CHECK: !0 = metadata !{metadata !"sp"}