1 files changed, 24 insertions, 0 deletions
diff --git a/test/CodeGen/AArch64/atomic-ops-not-barriers.ll b/test/CodeGen/AArch64/atomic-ops-not-barriers.ll
new file mode 100644
index 0000000000..f383d76b74
--- /dev/null
+++ b/test/CodeGen/AArch64/atomic-ops-not-barriers.ll
@@ -0,0 +1,24 @@
+; RUN: llc -march=aarch64 < %s | FileCheck %s
+
+define i32 @foo(i32* %var, i1 %cond) {
+; CHECK: foo:
+  br i1 %cond, label %atomic_ver, label %simple_ver
+simple_ver:
+  %oldval = load i32* %var
+  %newval = add nsw i32 %oldval, -1
+  store i32 %newval, i32* %var
+  br label %somewhere
+atomic_ver:
+  %val = atomicrmw add i32* %var, i32 -1 seq_cst
+  br label %somewhere
+; CHECK: dmb
+; CHECK: ldxr
+; CHECK: dmb
+  ; The key point here is that the second dmb isn't immediately followed by the
+  ; simple_ver basic block, which LLVM attempted to do when DMB had been marked
+  ; with isBarrier. For now, look for something that looks like "somewhere".
+; CHECK-NEXT: mov
+somewhere:
+  %combined = phi i32 [ %val, %atomic_ver ], [ %newval, %simple_ver]
+  ret i32 %combined
+}