2 files changed, 44 insertions, 0 deletions
diff --git a/tests/autodiff/select.slang b/tests/autodiff/select.slang
new file mode 100644
index 000000000..261c170db
--- /dev/null
+++ b/tests/autodiff/select.slang
@@ -0,0 +1,38 @@
+//TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -shaderobj -output-using-type
+//TEST(compute, vulkan):COMPARE_COMPUTE_EX:-vk -compute -shaderobj -output-using-type
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<float> outputBuffer;
+
+typedef DifferentialPair<float> dpfloat;
+typedef float.Differential dfloat;
+
+[BackwardDifferentiable]
+float f(float x, float y)
+{
+    return x > 0.5 ? x : y;
+}
+
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    {
+        dpfloat dpa = dpfloat(2.0, 1.0);
+        dpfloat dpb = dpfloat(0.5, 1.0);
+
+        __bwd_diff(f)(dpa, dpb, 1.0);
+
+        outputBuffer[0] = dpa.d;    // Expect: 1.0
+        outputBuffer[1] = dpb.d;    // Expect: 0.0
+    }
+
+    {
+        dpfloat dpa = dpfloat(0.3, 1.0);
+        dpfloat dpb = dpfloat(0.3, 1.0);
+
+        __bwd_diff(f)(dpa, dpb, 1.0);
+
+        outputBuffer[2] = dpa.d; // Expect: 0.0
+        outputBuffer[3] = dpb.d; // Expect: 1.0
+    }
+}
diff --git a/tests/autodiff/select.slang.expected.txt b/tests/autodiff/select.slang.expected.txt
new file mode 100644
index 000000000..52dd2d9ca
--- /dev/null
+++ b/tests/autodiff/select.slang.expected.txt
@@ -0,0 +1,6 @@
+type: float
+1.000000
+0.000000
+0.000000
+1.000000
+0.000000