1 files changed, 31 insertions, 0 deletions
diff --git a/test/CodeGen/AArch64/zero-reg.ll b/test/CodeGen/AArch64/zero-reg.ll
new file mode 100644
index 0000000..fef0437
--- /dev/null
+++ b/test/CodeGen/AArch64/zero-reg.ll
@@ -0,0 +1,31 @@
+; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu | FileCheck %s
+
+@var32 = global i32 0
+@var64 = global i64 0
+
+define void @test_zr() {
+; CHECK: test_zr:
+
+  store i32 0, i32* @var32
+; CHECK: str wzr, [{{x[0-9]+}}, #:lo12:var32]
+  store i64 0, i64* @var64
+; CHECK: str xzr, [{{x[0-9]+}}, #:lo12:var64]
+
+  ret void
+; CHECK: ret
+}
+
+define void @test_sp(i32 %val) {
+; CHECK: test_sp:
+
+; Important correctness point here is that LLVM doesn't try to use xzr
+; as an addressing register: "str w0, [xzr]" is not a valid A64
+; instruction (0b11111 in the Rn field would mean "sp").
+  %addr = getelementptr i32* null, i64 0
+  store i32 %val, i32* %addr
+; CHECK: mov x[[NULL:[0-9]+]], xzr
+; CHECK: str {{w[0-9]+}}, [x[[NULL]]]
+
+  ret void
+; CHECK: ret
+}
+\ No newline at end of file