Support custom backward derivative attribute. (#2594)

6 files changed, 149 insertions, 0 deletions

diff --git a/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang b/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang
new file mode 100644
index 000000000..bd0780174
--- /dev/null
+++ b/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang
@@ -0,0 +1,61 @@
+// Test calling differentiable function through dynamic dispatch.
+
+//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;
+
+[anyValueSize(16)]
+interface IInterface
+{
+    static float calc(float x);
+}
+
+struct A : IInterface
+{
+    static float calc(float x) { return 1.0; }
+};
+
+struct B : IInterface
+{
+    static float calc(float x) { return 2.0; }
+};
+
+void dsqr<T:IInterface>(T obj, inout DifferentialPair<float> x, float dOut)
+{
+    float diff = 2.0 * x.p * dOut;
+    updateDiff(x, diff);
+}
+
+[BackwardDerivative(dsqr)]
+float sqr<T:IInterface>(T obj, float x)
+{
+    return no_diff(obj.calc(x)) + x * x;
+}
+
+// Use automatically differentiated outer function to triger the primal/propagate func generation logic
+// on a function that has user provided backward derivative.
+[BackwardDifferentiable]
+float sqr_outter<T:IInterface>(T obj, float x)
+{
+    return sqr(obj, x);
+}
+
+//TEST_INPUT: type_conformance A:IInterface = 0
+//TEST_INPUT: type_conformance B:IInterface = 1
+
+
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    var obj = createDynamicObject<IInterface>(dispatchThreadID.x, 0); // A
+    var p = DifferentialPair<float>(2.0, 1.0);
+    __bwd_diff(sqr_outter)(obj, p, 1.0); // A.calc, expect 4
+    outputBuffer[0] = p.d;
+
+    obj = createDynamicObject<IInterface>(dispatchThreadID.x + 1, 0); // B
+    p = DifferentialPair<float>(1.5, 1.0);
+    __bwd_diff(sqr)(obj, p, 1.0);                                                     // A.calc, expect 4
+    outputBuffer[1] = p.d; // B.calc, expect 3
+}
diff --git a/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang.expected.txt b/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang.expected.txt
new file mode 100644
index 000000000..780ba6ed4
--- /dev/null
+++ b/tests/autodiff/dynamic-dispatch-custom-bwd-derivative.slang.expected.txt
@@ -0,0 +1,6 @@
+type: float
+4.000000
+3.000000
+0.000000
+0.000000
+0.000000
diff --git a/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang b/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang
new file mode 100644
index 000000000..930c1c82b
--- /dev/null
+++ b/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang
@@ -0,0 +1,53 @@
+// Test calling differentiable function through dynamic dispatch.
+
+//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;
+
+[anyValueSize(16)]
+interface IInterface
+{
+    static float calc(float x);
+}
+
+struct A : IInterface
+{
+    static float calc(float x) { return 1.0; }
+};
+
+struct B : IInterface
+{
+    static float calc(float x) { return 2.0; }
+};
+
+DifferentialPair<float> dsqr<T:IInterface>(T obj, DifferentialPair<float> x)
+{
+    float primal = obj.calc(x.p) + x.p * x.p;
+    float diff = 2.0 * x.p * x.d;
+    return diffPair(primal, diff);
+}
+
+[ForwardDerivative(dsqr)]
+float sqr<T:IInterface>(T obj, float x)
+{
+    return no_diff(obj.calc(x)) + x * x;
+}
+
+//TEST_INPUT: type_conformance A:IInterface = 0
+//TEST_INPUT: type_conformance B:IInterface = 1
+
+
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    var obj = createDynamicObject<IInterface>(dispatchThreadID.x, 0); // A
+    var p = DifferentialPair<float>(2.0, 1.0);
+   
+    outputBuffer[0] =  __fwd_diff(sqr)(obj, p).d; // A.calc, expect 4
+
+    obj = createDynamicObject<IInterface>(dispatchThreadID.x + 1, 0); // B
+    p = DifferentialPair<float>(1.5, 1.0);
+    outputBuffer[1] = __fwd_diff(sqr)(obj, p).d;  // B.calc, expect 3
+}
diff --git a/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang.expected.txt b/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang.expected.txt
new file mode 100644
index 000000000..780ba6ed4
--- /dev/null
+++ b/tests/autodiff/dynamic-dispatch-custom-fwd-derivative.slang.expected.txt
@@ -0,0 +1,6 @@
+type: float
+4.000000
+3.000000
+0.000000
+0.000000
+0.000000
diff --git a/tests/language-server/robustness-6.slang b/tests/language-server/robustness-6.slang
new file mode 100644
index 000000000..ef5924cf3
--- /dev/null
+++ b/tests/language-server/robustness-6.slang
@@ -0,0 +1,10 @@
+//TEST:LANG_SERVER:
+//HOVER:4,8
+
+float dsqr<T:II
+
+[ForwardDerivative(dsqr)]
+float sqr<T:IInterface>(T obj, float x)
+{
+    return no_diff(obj.calc(x)) + x * x;
+}
diff --git a/tests/language-server/robustness-6.slang.expected.txt b/tests/language-server/robustness-6.slang.expected.txt
new file mode 100644
index 000000000..d5aa6c8c9
--- /dev/null
+++ b/tests/language-server/robustness-6.slang.expected.txt
@@ -0,0 +1,13 @@
+--------
+range: 3,6 - 3,10
+content:
+```
+func dsqr<T>(T obj, float x) -> float
+```
+
+TEST:LANG_SERVER:  
+HOVER:4,8  
+
+{REDACTED}.slang(4)
+
+