COMPMID-499: Port Gaussian 3x3 and 5x5 to new validation

Change-Id: Icb82186cb97bd8d6e2c4c63f050ee44e5d753ff7
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/86926
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Moritz Pflanzer <moritz.pflanzer@arm.com>
diff --git a/tests/validation/CPP/Gaussian5x5.cpp b/tests/validation/CPP/Gaussian5x5.cpp
new file mode 100644
index 0000000..55bb287
--- /dev/null
+++ b/tests/validation/CPP/Gaussian5x5.cpp
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2017 ARM Limited.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include "arm_compute/core/Helpers.h"
+
+#include "Gaussian5x5.h"
+#include "Utils.h"
+
+namespace arm_compute
+{
+namespace test
+{
+namespace validation
+{
+namespace reference
+{
+template <typename T>
+SimpleTensor<T> gaussian5x5(const SimpleTensor<T> &src, BorderMode border_mode, T constant_border_value)
+{
+    SimpleTensor<T> dst(src.shape(), src.data_type());
+    const std::array<T, 25> filter{ {
+            1, 4, 6, 4, 1,
+            4, 16, 24, 16, 4,
+            6, 24, 36, 24, 6,
+            4, 16, 24, 16, 4,
+            1, 4, 6, 4, 1
+        } };
+    const float scale = 1.f / 256.f;
+    for(int element_idx = 0; element_idx < src.num_elements(); ++element_idx)
+    {
+        const Coordinates id = index2coord(src.shape(), element_idx);
+        apply_2d_spatial_filter(id, src, dst, TensorShape(5U, 5U), filter.data(), scale, border_mode, constant_border_value);
+    }
+    return dst;
+}
+
+template SimpleTensor<uint8_t> gaussian5x5(const SimpleTensor<uint8_t> &src, BorderMode border_mode, uint8_t constant_border_value);
+} // namespace reference
+} // namespace validation
+} // namespace test
+} // namespace arm_compute