2 files changed, 66 insertions, 0 deletions
diff --git a/tests/bugs/gh-3087-multi-entry-point.slang b/tests/bugs/gh-3087-multi-entry-point.slang
new file mode 100644
index 000000000..1bbbb9995
--- /dev/null
+++ b/tests/bugs/gh-3087-multi-entry-point.slang
@@ -0,0 +1,38 @@
+//TEST:SIMPLE(filecheck=CHECK): -target spirv -fvk-use-entrypoint-name -emit-spirv-directly
+
+// CHECK-DAG: OpEntryPoint Vertex
+// CHECK-DAG: OpEntryPoint Fragment
+
+// we should only have 1 'BuiltIn InstanceIndex' since the `Output` and `Input` semantic
+// for `InstanceIndex` should be converted to a non-builtin
+// CHECK-DAG: BuiltIn InstanceIndex
+// CHECK-NOT: BuiltIn InstanceIndex
+
+// We require 1 `Flat` for the fragment input `uint`
+// SPIRV: Flat
+// SPIRV-NOT: Flat
+
+struct VIn
+{
+    uint instanceID : SV_InstanceID;
+}
+
+struct VSOutput
+{
+    uint instanceID : SV_InstanceID;
+	float4 color : COLOR;
+};
+
+[shader("vertex")]
+VSOutput vmain(VIn vin) {
+    VSOutput t;
+    t.instanceID = vin.instanceID;
+    t.color = float4(0, 0, 0, 0);
+    return t;
+}
+
+[shader("pixel")]
+float4 pmain(VSOutput input) : SV_TARGET
+{
+	return float4(float(input.instanceID), input.color.xyz);
+}
diff --git a/tests/bugs/gh-3087.slang b/tests/bugs/gh-3087.slang
new file mode 100644
index 000000000..1f6fa98ce
--- /dev/null
+++ b/tests/bugs/gh-3087.slang
@@ -0,0 +1,28 @@
+//TEST:SIMPLE(filecheck=HLSL): -entry main -target hlsl
+//TEST:SIMPLE(filecheck=GLSL): -entry main -target glsl
+//TEST:SIMPLE(filecheck=SPIRV): -entry main -target spirv
+
+// HLSL-DAG: main
+// HLSL-DAG: SV_InstanceID
+
+// GLSL-DAG: main
+// GLSL-DAG: gl_InstanceIndex
+
+// SPIRV: OpEntryPoint
+// SPIRV-NOT: BuiltIn InstanceIndex
+// We require 1 `Flat` for the fragment input `uint`
+// SPIRV: Flat
+// SPIRV-NOT: Flat
+
+
+struct PSInput
+{
+    uint vInstance : SV_InstanceID;
+	float4 color : COLOR;
+};
+
+[shader("pixel")]
+float4 main(PSInput input) : SV_TARGET
+{
+	return input.color + float(input.vInstance).xxxx;
+}
+\ No newline at end of file