Cleanup builtin arithmetic interfaces. (#3317)

* wip: clean up IArithmetic

* wip.

* Cleanup builtin arithmetic interfaces.

* Fix.

* Fixes.

* Fix.

* Fix.

* Fix.

---------

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/tests/autodiff/generic-constructor.slang b/tests/autodiff/generic-constructor.slang
new file mode 100644
index 000000000..aad9824ec
--- /dev/null
+++ b/tests/autodiff/generic-constructor.slang
@@ -0,0 +1,39 @@
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-slang -compute -shaderobj -output-using-type
+//TEST(compute, vulkan):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-vk -compute -shaderobj -output-using-type
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<float> outputBuffer;
+
+interface IFoo : IDifferentiable
+{
+    [Differentiable]
+    __init(Differential v);
+}
+
+struct Impl : IFoo
+{
+    float x;
+
+    [Differentiable]
+    __init(Differential v)
+    {
+        x = v.x;
+    }
+}
+
+[Differentiable]
+float test(float x)
+{
+    Impl.Differential v0 = { x };
+    var v1 = Impl(v0);
+    return v1.x * v1.x;
+}
+
+[numthreads(1,1,1)]
+void computeMain(uint tid : SV_DispatchThreadID)
+{
+    var p = diffPair(3.0, 0.0);
+    bwd_diff(test)(p, 1.0);
+    outputBuffer[tid] = p.d;
+    // CHECK: 6.0
+}