Add basic Operator interface

- C facing interfaces
- Activation layer descriptor

Partially Resolves: COMPMID-4512

Signed-off-by: Georgios Pinitas <georgios.pinitas@arm.com>
Change-Id: I8530748fff178ca46d61bf2e40d3e543e93f340b
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/5908
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>

1 files changed, 150 insertions, 0 deletions

diff --git a/src/common/IOperator.h b/src/common/IOperator.h
new file mode 100644
index 0000000000..7fdb443acb
--- /dev/null
+++ b/src/common/IOperator.h
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2021 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_COMMON_IOPERATOR_H_
+#define SRC_COMMON_IOPERATOR_H_
+
+#include "src/common/IContext.h"
+#include "src/common/IQueue.h"
+
+#include <vector>
+
+struct AclOperator_
+{
+    arm_compute::detail::Header header{ arm_compute::detail::ObjectType::Operator, nullptr };
+
+protected:
+    AclOperator_()  = default;
+    ~AclOperator_() = default;
+};
+
+namespace arm_compute
+{
+// Forward declarations
+class ITensorPack;
+
+/** Structure to capture internally memory requirements */
+struct MemoryInfo
+{
+    MemoryInfo(AclTensorSlot slot_id, size_t size, size_t alignment) noexcept
+        : slot_id(slot_id),
+          size(size),
+          alignment(alignment)
+    {
+    }
+    AclTensorSlot slot_id;
+    size_t        size;
+    size_t        alignment;
+};
+using MemoryRequirements = std::vector<MemoryInfo>;
+
+/** Base class specifying the operator interface */
+class IOperator : public AclOperator_
+{
+public:
+    /** Explict Operator Constructor
+     *
+     * @param[in] ctx Context to be used by the operator
+     */
+    explicit IOperator(IContext *ctx)
+    {
+        this->header.ctx = ctx;
+        this->header.ctx->inc_ref();
+    }
+
+    /** Destructor */
+    virtual ~IOperator()
+    {
+        this->header.ctx->dec_ref();
+        this->header.type = detail::ObjectType::Invalid;
+    };
+
+    /** Checks if an operator is valid
+     *
+     * @return True if successful otherwise false
+     */
+    bool is_valid() const
+    {
+        return this->header.type == detail::ObjectType::Operator;
+    };
+
+    /** Run the kernels contained in the function
+     *
+     * @param[in] queue   Queue to run a kernel on
+     * @param[in] tensors Vector that contains the tensors to operate on
+     */
+    virtual StatusCode run(IQueue &queue, ITensorPack &tensors) = 0;
+
+    /** Prepare the operator for execution
+     *
+     * Any one off pre-processing step required by the function is handled here
+     *
+     * @param[in] constants Vector that contains the constants tensors.
+     *
+     * @note Prepare stage might not need all the function's buffers' backing memory to be available in order to execute
+     */
+    virtual StatusCode prepare(ITensorPack &constants)
+    {
+        ARM_COMPUTE_UNUSED(constants);
+        return StatusCode::Success;
+    }
+
+    /** Return the memory requirements required by the workspace
+     */
+    virtual MemoryRequirements workspace() const
+    {
+        return {};
+    }
+};
+
+/** Extract internal representation of an Operator
+ *
+ * @param[in] op Opaque operator pointer
+ *
+ * @return The internal representation as an IOperator
+ */
+inline IOperator *get_internal(AclOperator op)
+{
+    return static_cast<IOperator *>(op);
+}
+
+namespace detail
+{
+/** Check if an internal operator is valid
+ *
+ * @param[in] op Internal operator to check
+ *
+ * @return A status code
+ */
+inline StatusCode validate_internal_operator(const IOperator *op)
+{
+    if(op == nullptr || !op->is_valid())
+    {
+        ARM_COMPUTE_LOG_ERROR_ACL("[IOperator]: Invalid operator object");
+        return StatusCode::InvalidArgument;
+    }
+    return StatusCode::Success;
+}
+} // namespace detail
+} // namespace arm_compute
+#endif /* SRC_COMMON_IOPERATOR_H_ */