Cleaned up legacy differential type handling + type casting bugfixes (#2660)

2 files changed, 43 insertions, 0 deletions

diff --git a/tests/autodiff/reverse-uint-vector.slang b/tests/autodiff/reverse-uint-vector.slang
new file mode 100644
index 000000000..3c940c5de
--- /dev/null
+++ b/tests/autodiff/reverse-uint-vector.slang
@@ -0,0 +1,40 @@
+//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], stride=4):out,name=outputBuffer
+RWStructuredBuffer<float> outputBuffer;
+
+typedef DifferentialPair<float3> dpfloat3;
+typedef float3.Differential dfloat3;
+
+typedef DifferentialPair<float2> dpfloat2;
+typedef float2.Differential dfloat2;
+
+// This test case should hit a lot of conversion insts
+// kIROp_MakeVectorFromScalar (both uint and float), 
+// kIROp_CastIntToFloat, etc..
+// 
+[BackwardDifferentiable]
+float3 test_uint_offset(float3 x, float3 y)
+{
+    uint3 u4 = 1;
+
+    uint3 u5 = u4 + 2;
+
+    return x + y + u5;
+}
+
+
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    {
+        dpfloat3 dpx = dpfloat3(float3(2.0, 3.0, 4.0), float3(0.0, 0.0, 0.0));
+        dpfloat3 dpy = dpfloat3(float3(1.5, 2.5, 3.5), float3(0.0, 0.0, 0.0));
+
+        __bwd_diff(test_uint_offset)(dpx, dpy, dfloat3(1.0, 2.0, 3.0));
+        outputBuffer[0] = dpx.d.y; // Expect: 2
+        outputBuffer[1] = dpy.d.y; // Expect: 2
+    }
+
+}
\ No newline at end of file
diff --git a/tests/autodiff/reverse-uint-vector.slang.expected.txt b/tests/autodiff/reverse-uint-vector.slang.expected.txt
new file mode 100644
index 000000000..4ca096282
--- /dev/null
+++ b/tests/autodiff/reverse-uint-vector.slang.expected.txt
@@ -0,0 +1,3 @@
+type: float
+2.000000
+2.000000
\ No newline at end of file