allow extension of a concrete type to implement additional interface

Also support the scenario that the extension declares conformance to interface I, and a method M in I is already supported by the base implementation.

1 files changed, 49 insertions, 0 deletions

diff --git a/tests/compute/extension-multi-interface.slang b/tests/compute/extension-multi-interface.slang
new file mode 100644
index 000000000..6cc88f87c
--- /dev/null
+++ b/tests/compute/extension-multi-interface.slang
@@ -0,0 +1,49 @@
+//TEST(compute):COMPARE_COMPUTE:-xslang -use-ir
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):dxbinding(0),glbinding(0),out
+
+RWStructuredBuffer<float> outputBuffer;
+
+interface IAdd
+{
+    float addf(float u, float v);
+}
+
+interface ISub
+{
+    float subf(float u, float v);
+}
+
+interface IAddAndSub
+{
+    float addf(float u, float v);
+    float subf(float u, float v);    
+}
+
+struct Simple : IAdd
+{
+    float addf(float u, float v)
+    {
+        return u+v;
+    }
+};
+
+__extension Simple : ISub, IAddAndSub
+{
+    float subf(float u, float v)
+    {
+        return u-v;
+    }
+};
+
+float testAddSub<T:IAddAndSub>(T t)
+{
+    return t.subf(t.addf(1.0, 1.0), 1.0);
+}
+
+[numthreads(4, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    Simple s;
+	float outVal = testAddSub(s);
+	outputBuffer[dispatchThreadID.x] = outVal;
+}
\ No newline at end of file