1 files changed, 37 insertions, 0 deletions
diff --git a/backend/unittests/CodeGen/LiveRegUnitsTest.cpp b/backend/unittests/CodeGen/LiveRegUnitsTest.cpp
new file mode 100644
index 0000000..7f224ac
--- /dev/null
+++ b/backend/unittests/CodeGen/LiveRegUnitsTest.cpp
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "rcc/CodeGen/LiveRegUnits.h"
+
+#include "LiveTestSupport.h"
+
+namespace {
+
+using namespace rcc::test::liveness;
+
+void testLiveRegUnits(TestContext &Context) {
+  const rcc::RegisterUnitID Unit = rcc::RegisterUnitID::fromValue(9);
+  rcc::LiveRegUnits Present;
+  rcc::LiveRegUnits Removed;
+  Present.add(Unit, rcc::LaneMask::fromRaw(0x3));
+  Removed.add(Unit, rcc::LaneMask::fromRaw(0x2));
+  Present.subtract(Removed);
+  Context.expect(Present.lanes(Unit) == rcc::LaneMask::fromRaw(0x1) &&
+                     Present.contains(Unit, rcc::LaneMask::fromRaw(0x1)) &&
+                     !Present.intersects(Unit, rcc::LaneMask::fromRaw(0x2)),
+                 "LiveRegUnits must preserve partial union and subtraction");
+  Present.unite(Removed);
+  Context.expect(Present.contains(Unit, rcc::LaneMask::fromRaw(0x3)),
+                 "LiveRegUnits union must restore all selected lanes");
+}
+
+} // namespace
+
+int main() {
+  TestContext Context;
+  auto Target = createTarget();
+  Context.expect(Target.has_value(), "liveness TestTarget must be created");
+  if (!Target)
+    return Context.result();
+  testLiveRegUnits(Context);
+  return Context.result();
+}