diff --git a/tests/hlsl/cast-64-bit.shader_test b/tests/hlsl/cast-64-bit.shader_test
index 53ed6c4d..bb17eb5f 100644
--- a/tests/hlsl/cast-64-bit.shader_test
+++ b/tests/hlsl/cast-64-bit.shader_test
@@ -105,3 +105,39 @@ uniform 0 int64_t2 -21474836481 0x100000002
 uniform 4 int4 -20 8 0 0
 draw quad
 probe (0, 0) rgba (-1.0, 2.0, 1073741824.0, 536870912.0)
+
+[require]
+shader model >= 6.2
+native-16-bit
+float64
+
+[pixel shader todo]
+uniform double2 d;
+
+int4 main() : sv_target
+{
+    int16_t4 s = int16_t4(d, d);
+    return s * int16_t4(2, 2, 1, 1);
+}
+
+[test]
+uniform 0 double2 0.5 1.0
+draw quad
+probe (0, 0) rgbai(0, 2, 0, 1)
+uniform 0 double2 -0.5 -1.0
+draw quad
+probe (0, 0) rgbai(0, -2, 0, -1)
+
+[pixel shader]
+uniform double2 d;
+
+uint4 main() : sv_target
+{
+    uint16_t4 s = uint16_t4(d, d);
+    return s * uint16_t4(2, 2, 1, 1);
+}
+
+[test]
+uniform 0 double2 0.5 1.0
+todo draw quad
+probe (0, 0) rgbaui(0, 2, 0, 1)