COMPMID-3637: Move utility headers from arm_compute to src

Signed-off-by: Georgios Pinitas <georgios.pinitas@arm.com>
Change-Id: If9d6fa8c900b68c4b6fd373f2fc1f9abb83ea917
Signed-off-by: Michalis Spyrou <michalis.spyrou@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/4145
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Sang-Hoon Park <sang-hoon.park@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/runtime/SchedulerUtils.h b/src/runtime/SchedulerUtils.h
new file mode 100644
index 0000000..46644a3
--- /dev/null
+++ b/src/runtime/SchedulerUtils.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2020 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.
+ */
+#ifndef SRC_COMPUTE_SCHEDULER_UTILS_H
+#define SRC_COMPUTE_SCHEDULER_UTILS_H
+
+#include <cstddef>
+#include <utility>
+
+namespace arm_compute
+{
+namespace scheduler_utils
+{
+/** Given two dimensions and a maximum number of threads to utilise, calculate the best
+ * combination of threads that fit in (multiplied together) max_threads.
+ *
+ * This algorithm assumes that work in either of the dimensions is equally difficult
+ * to compute
+ *
+ * @returns [m_nthreads, n_nthreads] A pair of the threads that should be used in each dimension
+ */
+std::pair<unsigned, unsigned> split_2d(unsigned max_threads, std::size_t m, std::size_t n);
+} // namespace scheduler_utils
+} // namespace arm_compute
+#endif /* SRC_COMPUTE_SCHEDULER_UTILS_H */