Adds Tests and reference implementation for scatter operator with 1D tensors.

Resolves: [COMPMID-6890]
Change-Id: Ie4a8db24fc6387afa9ddf42b3607e040cdf8df67
Signed-off-by: Mohammed Suhail Munshi <MohammedSuhail.Munshi@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/11339
Reviewed-by: Gunes Bayir <gunes.bayir@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Benchmark: Arm Jenkins <bsgcomp@arm.com>

1 files changed, 59 insertions, 5 deletions

diff --git a/tests/validation/reference/ScatterLayer.cpp b/tests/validation/reference/ScatterLayer.cpp
index 188cce100b..920f2b9990 100644
--- a/tests/validation/reference/ScatterLayer.cpp
+++ b/tests/validation/reference/ScatterLayer.cpp
@@ -32,16 +32,70 @@ namespace validation
 {
 namespace reference
 {
+namespace
+{
 
 template <typename T>
+T reduce_op(const T &current,const T &update,const ScatterFunction func)
+{
+    switch(func)
+    {
+        case ScatterFunction::Update:
+            return update;
+            break;
+        case ScatterFunction::Add:
+            return current + update;
+            break;
+        case ScatterFunction::Sub:
+            return current - update;
+            break;
+        case ScatterFunction::Max:
+            return std::max(current, update);
+            break;
+        case ScatterFunction::Min:
+            return std::min(current, update);
+            break;
+        default:
+            ARM_COMPUTE_ERROR("Unsupported Scatter function");
+            break;
+    }
+}
+
+template float reduce_op(const float &current,const float &update,const ScatterFunction func);
+}
+
+// Note : This function currently only supports 1D src, 1D updates, 2D indices, 1D output tensors.
+template <typename T>
 SimpleTensor<T> scatter_layer_internal(const SimpleTensor<T> &src, const SimpleTensor<T> &updates, const SimpleTensor<uint32_t> &indices, const TensorShape &out_shape, const ScatterInfo &info)
 {
-    ARM_COMPUTE_UNUSED(src);
-    ARM_COMPUTE_UNUSED(updates);
-    ARM_COMPUTE_UNUSED(indices);
-    ARM_COMPUTE_UNUSED(info);
-    // Unimplemented reference.
     SimpleTensor<T> dst{ out_shape, src.data_type(), 1 };
+
+    // 1. If zero initialization variable is true, fill dst with 0 values. Else copy src data to dst.
+    if(info.zero_initialization)
+    {
+        for (int i = 0; i < src.num_elements(); ++i)
+        {
+            dst[i] = static_cast<T>(0);
+        }
+    }
+    else
+    {
+        std::copy_n(src.data(), src.num_elements(), dst.data());
+    }
+
+    // 2. Get max index of output tensor, then iterate over index tensor.
+    const auto x_bound = dst.shape().x();
+
+
+    for(int i = 0; i < indices.num_elements(); ++i)
+    {
+        // 3. Check whether index is out of bounds for dst, if not then apply reduce op.
+        const auto index = indices[i];
+        if (index < x_bound) // Note : index is always >= 0 as datatype is unsigned.
+        {
+            dst[index] = reduce_op(dst[index], updates[i], info.func);
+        }
+    }
     return dst;
 }