/*************************************************************************
 * Copyright (c) 2019-2021 Advanced Micro Devices, Inc. All rights reserved.
 *
 * See LICENSE.txt for license information
 ************************************************************************/
#ifndef TEST_ALLREDUCE_MULTI_PROCESS_HPP
#define TEST_ALLREDUCE_MULTI_PROCESS_HPP

#include "CorrectnessTest.hpp"

namespace CorrectnessTests
{
    class AllReduceMultiProcessCorrectnessTest : public MultiProcessCorrectnessTest
    {
    public:
        static void ComputeExpectedResults(Dataset& dataset, Barrier& barrier, ncclRedOp_t const op, std::vector<int> const& ranks)
        {
            // Copy all inputs to expected arrays temporarily to perform reduction on host
            for (int i = 0; i < ranks.size(); i++)
            {
                int rank = ranks[i];
                HIP_CALL(hipMemcpy(dataset.expected[rank], dataset.inputs[rank],
                                   dataset.NumBytes(), hipMemcpyDeviceToHost));
            }
            barrier.Wait();

            // Allocate temporary host array to accumulate results
            int8_t*   resultI1 = (int8_t   *)malloc(dataset.NumBytes());
            uint8_t*  resultU1 = (uint8_t  *)resultI1;
            int32_t*  resultI4 = (int32_t  *)resultI1;
            uint32_t* resultU4 = (uint32_t *)resultI1;
            int64_t*  resultI8 = (int64_t  *)resultI1;
            uint64_t* resultU8 = (uint64_t *)resultI1;
            float*    resultF4 = (float    *)resultI1;
            double*   resultF8 = (double   *)resultI1;
            rccl_bfloat16* resultB2 = (rccl_bfloat16 *)resultI1;

            // Initialize the result with the first device's array
            memcpy(resultI1, dataset.expected[0], dataset.NumBytes());
            barrier.Wait();

            // Perform reduction
            for (int i = 1; i < dataset.numDevices; i++)
            {
                int8_t*   arrayI1 = (int8_t   *)dataset.expected[i];
                uint8_t*  arrayU1 = (uint8_t  *)arrayI1;
                int32_t*  arrayI4 = (int32_t  *)arrayI1;
                uint32_t* arrayU4 = (uint32_t *)arrayI1;
                int64_t*  arrayI8 = (int64_t  *)arrayI1;
                uint64_t* arrayU8 = (uint64_t *)arrayI1;
                float*    arrayF4 = (float    *)arrayI1;
                double*   arrayF8 = (double   *)arrayI1;
                rccl_bfloat16* arrayB2 = (rccl_bfloat16 *)arrayI1;

                for (int j = 0; j < dataset.numElements; j++)
                {
                    switch (dataset.dataType)
                    {
                    case ncclInt8:    resultI1[j] = ReduceOp(op, resultI1[j], arrayI1[j]); break;
                    case ncclUint8:   resultU1[j] = ReduceOp(op, resultU1[j], arrayU1[j]); break;
                    case ncclInt32:   resultI4[j] = ReduceOp(op, resultI4[j], arrayI4[j]); break;
                    case ncclUint32:  resultU4[j] = ReduceOp(op, resultU4[j], arrayU4[j]); break;
                    case ncclInt64:   resultI8[j] = ReduceOp(op, resultI8[j], arrayI8[j]); break;
                    case ncclUint64:  resultU8[j] = ReduceOp(op, resultU8[j], arrayU8[j]); break;
                    case ncclFloat32: resultF4[j] = ReduceOp(op, resultF4[j], arrayF4[j]); break;
                    case ncclFloat64: resultF8[j] = ReduceOp(op, resultF8[j], arrayF8[j]); break;
                    case ncclBfloat16: resultB2[j] = ReduceOp(op, resultB2[j], arrayB2[j]); break;
                    default:
                        fprintf(stderr, "[ERROR] Unsupported datatype\n");
                        exit(0);
                    }
                }
            }
            barrier.Wait();

            // Copy results into expected array
            for (int i = 0; i < ranks.size(); i++)
            {
                int rank = ranks[i];
                memcpy(dataset.expected[rank], resultI1, dataset.NumBytes());
            }
            free(resultI1);
        }

        void TestAllReduce(int rank, Dataset& dataset, bool& pass)
        {
            SetUpPerProcess(rank, ncclCollAllReduce, comms[rank], streams[rank], dataset);

            if (numDevices > numDevicesAvailable)
            {
                pass = true;
                return;
            }

            Barrier barrier(rank, numDevices, StripPortNumberFromCommId(std::string(getenv("NCCL_COMM_ID"))));

            // Prepare input / output / expected results
            FillDatasetWithPattern(dataset, rank);
            ComputeExpectedResults(dataset, barrier, op, std::vector<int>(1, rank));

            // Launch the reduction
            ncclAllReduce(dataset.inputs[rank], dataset.outputs[rank],
                          numElements, dataType, op, comms[rank], streams[rank]);

            // Wait for reduction to complete
            HIP_CALL(hipStreamSynchronize(streams[rank]));

            // Check results
            pass = ValidateResults(dataset, rank);

            TearDownPerProcess(comms[rank], streams[rank]);
            dataset.Release(rank);
        }
    };
}

#endif