/*************************************************************************
 * Copyright (c) 2016-2022, NVIDIA CORPORATION. All rights reserved.
 * Modifications Copyright (c) 2022 Advanced Micro Devices, Inc. All rights reserved.
 *
 * See LICENSE.txt for license information
 ************************************************************************/

#include "common.h"
#include "cuda_runtime.h"

#define ALIGN 4

void
HyperCubeGetCollByteCount(size_t* sendcount, size_t* recvcount, size_t* paramcount,
                          size_t* sendInplaceOffset, size_t* recvInplaceOffset,
                          size_t count, size_t eltSize, int nranks)
{
    size_t base        = (count / nranks) & -(16 / eltSize);
    *sendcount         = base;
    *recvcount         = base * nranks;
    *sendInplaceOffset = base;
    *recvInplaceOffset = 0;
    *paramcount        = base;
}

testResult_t
HyperCubeInitData(struct threadArgs* args, ncclDataType_t type, ncclRedOp_t op, int root,
                  int rep, int in_place)
{
    size_t sendcount = args->sendBytes / wordSize(type);
    size_t recvcount = args->expectedBytes / wordSize(type);
    int    nranks    = args->nProcs * args->nThreads * args->nGpus;

    for(int i = 0; i < args->nGpus; i++)
    {
        CUDACHECK(cudaSetDevice(args->gpus[i]));
        int rank = ((args->proc * args->nThreads + args->thread) * args->nGpus + i);
        CUDACHECK(cudaMemset(args->recvbuffs[i], 0, args->expectedBytes));
        void* data = in_place ? ((char*) args->recvbuffs[i]) + rank * args->sendBytes
                              : args->sendbuffs[i];
        TESTCHECK(InitData(data, sendcount, 0, type, ncclSum, 33 * rep + rank, 1, 0));
        for(int j = 0; j < nranks; j++)
        {
            TESTCHECK(InitData((char*) args->expected[i] + args->sendBytes * j, sendcount,
                               0, type, ncclSum, 33 * rep + j, 1, 0));
        }
        CUDACHECK(cudaDeviceSynchronize());
    }
    return testSuccess;
}

void
HyperCubeGetBw(size_t count, int typesize, double sec, double* algBw, double* busBw,
               int nranks)
{
    double baseBw = (double) (count * typesize * (nranks - 1)) / 1.0E9 / sec;

    *algBw        = baseBw;
    double factor = 1;
    *busBw        = baseBw * factor;
}

testResult_t
HyperCubeRunColl(void* sendbuff, void* recvbuff, size_t count, ncclDataType_t type,
                 ncclRedOp_t op, int root, ncclComm_t comm, cudaStream_t stream)
{
    char* sbuff = (char*) sendbuff;
    char* rbuff = (char*) recvbuff;
    int   nRanks;
    NCCLCHECK(ncclCommCount(comm, &nRanks));
    int rank;
    NCCLCHECK(ncclCommUserRank(comm, &rank));
    size_t rankSize = count * wordSize(type);
    if(rbuff + rank * rankSize != sbuff)
        CUDACHECK(cudaMemcpyAsync(rbuff + rank * rankSize, sbuff, rankSize,
                                  cudaMemcpyDeviceToDevice, stream));

    // Hypercube AllGather
    for(int mask = 1; mask < nRanks; mask <<= 1)
    {
        NCCLCHECK(ncclGroupStart());
        int s = rank & ~(mask - 1);
        int r = s ^ mask;
        NCCLCHECK(ncclSend(rbuff + s * rankSize, count * mask, type, rank ^ mask, comm,
                           stream));
        NCCLCHECK(ncclRecv(rbuff + r * rankSize, count * mask, type, rank ^ mask, comm,
                           stream));
        NCCLCHECK(ncclGroupEnd());
    }
    return testSuccess;
}

struct testColl hyperCubeTest = { "HyperCube", HyperCubeGetCollByteCount,
                                  HyperCubeInitData, HyperCubeGetBw, HyperCubeRunColl };

void
HyperCubeGetBuffSize(size_t* sendcount, size_t* recvcount, size_t count, int nranks)
{
    size_t paramcount, sendInplaceOffset, recvInplaceOffset;
    HyperCubeGetCollByteCount(sendcount, recvcount, &paramcount, &sendInplaceOffset,
                              &recvInplaceOffset, count, /*eltSize=*/1, nranks);
}

testResult_t
HyperCubeRunTest(struct threadArgs* args, int root, ncclDataType_t type,
                 const char* typeName, ncclRedOp_t op, const char* opName)
{
    args->collTest = &hyperCubeTest;
    ncclDataType_t* run_types;
    const char**    run_typenames;
    int             type_count;

    if((int) type != -1)
    {
        type_count    = 1;
        run_types     = &type;
        run_typenames = &typeName;
    }
    else
    {
        type_count    = test_typenum;
        run_types     = test_types;
        run_typenames = test_typenames;
    }

    // Check if this is a power of 2
    int nRanks = args->nProcs * args->nThreads * args->nGpus;
    if(nRanks && !(nRanks & (nRanks - 1)))
    {
        for(int i = 0; i < type_count; i++)
        {
            TESTCHECK(
                TimeTest(args, run_types[i], run_typenames[i], (ncclRedOp_t) 0, "", -1));
        }
    }
    else
    {
        printf("nRanks %d is not a power of 2, skipping\n", nRanks);
    }

    return testSuccess;
}

struct testEngine ncclTestEngine = { HyperCubeGetBuffSize, HyperCubeRunTest };