#include <cstdint>
#include <c10/util/Exception.h>
#include <c10/core/Scalar.h>
#include <c10/core/ScalarType.h>
#define TORCH_ASSERT_ONLY_METHOD_OPERATORS
#include <ATen/core/Tensor.h>
#include <ATen/core/NamedTensor.h>
#include <ATen/Dispatch.h>
#include <ATen/ExpandUtils.h>
#include <ATen/OpMathType.h>
#include <ATen/TensorUtils.h>
#include <ATen/cuda/CUDABlas.h>
#include <ATen/cuda/tunable/Tunable.h>
#include <ATen/cuda/tunable/TunableGemm.h>
#include <ATen/native/Resize.h>
#include <c10/util/MaybeOwned.h>
#include <ATen/native/cuda/RowwiseScaledMM.h>

#ifndef AT_PER_OPERATOR_HEADERS
#include <ATen/Functions.h>
#include <ATen/NativeFunctions.h>
#else
#include <ATen/ops/_addmm_activation_native.h>
#include <ATen/ops/_efficientzerotensor.h>
#include <ATen/ops/_scaled_mm_native.h>
#include <ATen/ops/_unsafe_view_native.h>
#include <ATen/ops/abs.h>
#include <ATen/ops/addmm_native.h>
#include <ATen/ops/addmv_native.h>
#include <ATen/ops/baddbmm_native.h>
#include <ATen/ops/bmm_native.h>
#include <ATen/ops/copy_native.h>
#include <ATen/ops/dot_native.h>
#include <ATen/ops/empty.h>
#include <ATen/ops/gelu.h>
#include <ATen/ops/max.h>
#include <ATen/ops/mm_native.h>
#include <ATen/ops/mul.h>
#include <ATen/ops/relu.h>
#include <ATen/ops/ones.h>
#include <ATen/ops/scalar_tensor_native.h>
#include <ATen/ops/vdot_native.h>
#endif

namespace at::native {

namespace {

// TODO: https://github.com/pytorch/pytorch/pull/59380#pullrequestreview-725310492
c10::MaybeOwned<Tensor> inline resolve_conj_if_indicated(const Tensor& tensor, bool resolve_conj) {
  if (resolve_conj && tensor.is_conj()) {
    return c10::MaybeOwned<Tensor>::owned(tensor.resolve_conj());
  } else {
    return c10::MaybeOwned<Tensor>::borrowed(tensor);
  }
}

c10::MaybeOwned<Tensor> inline prepare_matrix_for_cublas(const Tensor& tensor, bool& transpose_tensor, bool transpose_result) {
  if (tensor.is_non_overlapping_and_dense()) { // common case
      transpose_tensor = tensor.is_contiguous();
      return resolve_conj_if_indicated(tensor, transpose_result ? transpose_tensor : !transpose_tensor);
  }
  IntArrayRef tensor_strides = tensor.strides();
  IntArrayRef tensor_sizes = tensor.sizes();
  if ((tensor_strides[0] == 1) && (tensor_strides[1] >= std::max<int64_t>(1, tensor_sizes[0]))) {
    transpose_tensor = false;
    return resolve_conj_if_indicated(tensor, !transpose_result);
  } else if ((tensor_strides[1] == 1) && (tensor_strides[0] >= std::max<int64_t>(1, tensor_sizes[1]))) {
    transpose_tensor = true;
    return resolve_conj_if_indicated(tensor, transpose_result);
  } else {
    transpose_tensor = true;
    return c10::MaybeOwned<Tensor>::owned(tensor.clone(at::MemoryFormat::Contiguous));
  }
}

c10::MaybeOwned<Tensor> inline prepare_matrix_for_cublas(const Tensor& tensor, bool& transpose_tensor) {
  if (tensor.is_non_overlapping_and_dense()) { // common case
      transpose_tensor = tensor.is_contiguous();
      return resolve_conj_if_indicated(tensor, true);
  }
  IntArrayRef tensor_strides = tensor.strides();
  IntArrayRef tensor_sizes = tensor.sizes();
  if ((tensor_strides[0] == 1) && (tensor_strides[1] >= std::max<int64_t>(1, tensor_sizes[0]))) {
    transpose_tensor = false;
    return resolve_conj_if_indicated(tensor, true);
  } else if ((tensor_strides[1] == 1) && (tensor_strides[0] >= std::max<int64_t>(1, tensor_sizes[1]))) {
    transpose_tensor = true;
    return resolve_conj_if_indicated(tensor, true);
  } else {
    transpose_tensor = true;
    return c10::MaybeOwned<Tensor>::owned(tensor.clone(at::MemoryFormat::Contiguous));
  }
}

struct cublasCommonArgs {
  cublasCommonArgs(const Tensor& mat1, const Tensor& mat2, Tensor& c) {
    bool transpose_result, transpose_mat1, transpose_mat2;
    result = prepare_matrix_for_cublas(c, transpose_result);
    mata = prepare_matrix_for_cublas(transpose_result ? mat2 : mat1, transpose_mat1, transpose_result);
    matb = prepare_matrix_for_cublas(transpose_result ? mat1 : mat2, transpose_mat2, transpose_result);
    auto mat1_sizes = mat1.sizes();
    auto mat2_sizes = mat2.sizes();
    if (transpose_result) {
      transpose_mat1 = !transpose_mat1;
      transpose_mat2 = !transpose_mat2;
      mat1_sizes = mata->sizes();
      mat2_sizes = matb->sizes();
    }

    m = mat1_sizes[transpose_result ? 1 : 0];
    k = mat1_sizes[transpose_result ? 0 : 1];
    n = mat2_sizes[transpose_result ? 0 : 1];
    lda = mata->stride((transpose_mat1 == transpose_result) ? 1 : 0);
    ldb = matb->stride((transpose_mat2 == transpose_result) ? 1 : 0);
    result_ld = result->stride(transpose_result ? 0 : 1);
    transa = transpose_mat1 ?  mata->is_conj() ? 'c' : 't' : 'n';
    transb = transpose_mat2 ?  matb->is_conj() ? 'c' : 't' : 'n';
  }
  char transa, transb;
  int64_t m, n, k;
  int64_t lda, ldb, result_ld;
  c10::MaybeOwned<Tensor> mata, matb, result;
};
} // namespace

c10::MaybeOwned<Tensor> prepare_batch_matrix_for_cublas(const Tensor& tensor, bool& transpose_tensor, int64_t& ld_tensor, bool transpose_result, int64_t m, int64_t n) {
  IntArrayRef tensor_strides = tensor.strides();
  c10::MaybeOwned<Tensor> tensor_;
  int fast_dim = transpose_result ? 2 : 1;
  int leading_dim = transpose_result ? 1 : 2;

  if (tensor_strides[fast_dim] == 1 &&
    (tensor_strides[leading_dim] >= std::max<int64_t>(1, m))) {
    transpose_tensor = false;
    tensor_ = resolve_conj_if_indicated(tensor, true);
    ld_tensor = tensor_->strides()[leading_dim];
  } else if ((tensor_strides[leading_dim] == 1) &&
    (tensor_strides[fast_dim] >= std::max<int64_t>(1, n))) {
    transpose_tensor = true;
    tensor_ = resolve_conj_if_indicated(tensor, false);
    ld_tensor = tensor_->strides()[fast_dim];
  } else {
    transpose_tensor = !transpose_result;
    // gemm call requires leading dimension and stride parameters to be non-zero
    bool is_stride_non_zero = tensor.strides()[1] != 0 && tensor.strides()[2] != 0;
    if (tensor.is_contiguous() && is_stride_non_zero) {
      tensor_ = resolve_conj_if_indicated(tensor, transpose_result);
    } else {
      tensor_ = c10::MaybeOwned<Tensor>::owned(tensor.clone(at::MemoryFormat::Contiguous));
    }
    ld_tensor = tensor_->strides()[1];
  }

  return tensor_;
}

namespace {

enum class Activation {
  None,
  RELU,
  GELU,
};

cuda::blas::GEMMAndBiasActivationEpilogue activation_to_gemm_and_blas_arg(Activation a) {
  switch (a) {
    case Activation::None:
      return cuda::blas::GEMMAndBiasActivationEpilogue::None;
    case Activation::RELU:
      return cuda::blas::GEMMAndBiasActivationEpilogue::RELU;
    case Activation::GELU:
      return cuda::blas::GEMMAndBiasActivationEpilogue::GELU;
    default:
      TORCH_CHECK(false);
      return cuda::blas::GEMMAndBiasActivationEpilogue::None;
  }
}

static bool getDisableAddmmCudaLt() {
    static const char* env_value = std::getenv("DISABLE_ADDMM_CUDA_LT");
#ifdef USE_ROCM
    // allow both CUDA and HIP env var names for ROCm builds
    // also, current default for ROCm builds is disable by default
    if (env_value == nullptr) {
        env_value = std::getenv("DISABLE_ADDMM_HIP_LT");
    }
    if (env_value != nullptr && strcmp(env_value, "0") == 0) {
      return false;
    }
    return true;
#else
    if (env_value != nullptr && strcmp(env_value, "1") == 0) {
      return true;
    }
    return false;
#endif
}

#ifdef USE_ROCM
static bool isSupportedHipLtROCmArch(int index) {
    hipDeviceProp_t* prop = at::cuda::getDeviceProperties(index);
    std::string device_arch = prop->gcnArchName;
    static const std::vector<std::string> archs = {"gfx90a", "gfx940", "gfx941", "gfx942"};
    for (std::string arch : archs) {
        size_t substring = device_arch.find(arch);
        if (substring != std::string::npos) {
            return true;
        }
    }
    TORCH_CHECK(false, "Attempting to use hipBLASLt on a unsupported architecture!");
    return false;
}
#endif

template <typename scalar_t>
static void launchTunableGemmAndBias(cublasCommonArgs &args, const Scalar& alpha, const scalar_t* bias, cuda::blas::GEMMAndBiasActivationEpilogue activation) {
  bool transa_ = ((args.transa != 'n') && (args.transa != 'N'));
  bool transb_ = ((args.transb != 'n') && (args.transb != 'N'));
  at::cuda::tunable::GemmAndBiasParams<scalar_t> params;
  params.transa = args.transa;
  params.transb = args.transb;
  params.m = args.m;
  params.n = args.n;
  params.k = args.k;
  params.alpha = alpha.to<at::opmath_type<scalar_t>>();
  params.a = args.mata->const_data_ptr<scalar_t>();
  params.lda = args.lda;
  params.b = args.matb->const_data_ptr<scalar_t>();
  params.ldb = args.ldb;
  params.c = args.result->data_ptr<scalar_t>();
  params.ldc = args.result_ld;
  params.bias = bias;
  params.activation = activation;
  if (transa_ && transb_) {
    static at::cuda::tunable::GemmAndBiasTunableOp<scalar_t, at::cuda::tunable::BlasOp::T, at::cuda::tunable::BlasOp::T> gemm{};
    gemm(&params);
  }
  else if (transa_ && !transb_) {
    static at::cuda::tunable::GemmAndBiasTunableOp<scalar_t, at::cuda::tunable::BlasOp::T, at::cuda::tunable::BlasOp::N> gemm{};
    gemm(&params);
  }
  else if (!transa_ && transb_) {
    static at::cuda::tunable::GemmAndBiasTunableOp<scalar_t, at::cuda::tunable::BlasOp::N, at::cuda::tunable::BlasOp::T> gemm{};
    gemm(&params);
  }
  else if (!transa_ && !transb_) {
    static at::cuda::tunable::GemmAndBiasTunableOp<scalar_t, at::cuda::tunable::BlasOp::N, at::cuda::tunable::BlasOp::N> gemm{};
    gemm(&params);
  }
  else {
    TORCH_CHECK(false, "unreachable");
  }
}

Tensor& addmm_out_cuda_impl(Tensor& result, const Tensor& self, const Tensor& mat1, const Tensor& mat2, const Scalar& beta, const Scalar& alpha, Activation activation=Activation::None) {
  // Make sure to keep addmm_cuda below in sync with this code; it
  // preflights a check to try to avoid actually needing to call
  // expand().
  TORCH_CHECK(mat1.dim() == 2 && mat2.dim() == 2, "tensors must be 2-D");
  TORCH_CHECK(
    mat1.dtype() == mat2.dtype(),
    "expected mat1 and mat2 to have the same dtype, but got: ", mat1.dtype(), " != ", mat2.dtype()
  )

  TensorArg targs[]{{result, "out", 0}, {self, "self", 1}, {mat1, "mat1", 2}, {mat2, "mat2", 3}};
  checkAllSameGPU(__func__, targs);

  IntArrayRef mat1_sizes = mat1.sizes();
  IntArrayRef mat2_sizes = mat2.sizes();
  IntArrayRef self__sizes;
  bool useLtInterface = false;
  static bool disable_addmm_cuda_lt = getDisableAddmmCudaLt();
  at::ScalarType scalar_type = self.scalar_type();
  c10::MaybeOwned<Tensor> self_;
  if (&result != &self) {
#if (defined(CUDA_VERSION) && (CUDA_VERSION >= 11040)) || defined(USE_ROCM)
    // Strangely, if mat2 has only 1 row or column, we get
    // CUBLAS_STATUS_INVALID_VALUE error from cublasLtMatmulAlgoGetHeuristic.
    // self.dim() == 1 && result.dim() == 2 && self.sizes()[0] == mat2_sizes[1]
    // is to use lt interface only when self is bias.
    // for cuda 11.4, cublasLtMatmul is activated
    // the last two conditions is to skip 16b transA and non-trans-B having
    // leading dim >> rows when they are sliced from a large tensor
    // see fbcode/caffe2/test/test_linalg.py:test_corner_cases_of_cublasltmatmul
    if (!disable_addmm_cuda_lt) {
      useLtInterface = beta.toComplexDouble() == 1.0 && self.dim() == 1 &&
          result.dim() == 2 && self.sizes()[0] == mat2_sizes[1] &&
          self.is_contiguous() && result.is_contiguous() &&
#ifdef USE_ROCM
          isSupportedHipLtROCmArch(self.device().index()) &&
          (scalar_type == at::ScalarType::Float ||
           scalar_type == at::ScalarType::Half ||
           scalar_type == at::ScalarType::BFloat16) &&
#else
          (scalar_type == at::ScalarType::Double ||
           scalar_type == at::ScalarType::Float ||
           scalar_type == at::ScalarType::Half ||
           scalar_type == at::ScalarType::BFloat16) &&
#endif
#if (defined(CUDA_VERSION) && CUDA_VERSION >= 12010 && !defined(USE_ROCM))
          mat2_sizes[0] > 1 && mat2_sizes[1] > 1;
#else
          mat2_sizes[0] > 1 && mat2_sizes[1] > 1 &&
          mat2_sizes[0] < 65535 * 32 && mat2_sizes[1] < 65535 * 32 &&
          mat1_sizes[0] < 65535 * 32 && mat1_sizes[1] < 65535 * 32 &&
          // avoid leading dim >> rows bugs
          ((mat1.strides()[0] == 1 && mat1.strides()[1] == mat1_sizes[0]) ||
           (mat1.strides()[1] == 1 && mat1.strides()[0] == mat1_sizes[1]) ||
           (scalar_type != at::ScalarType::Half &&
            scalar_type != at::ScalarType::BFloat16)) &&
          ((mat2.strides()[0] == 1 && mat2.strides()[1] == mat2_sizes[0]) ||
           (mat2.strides()[1] == 1 && mat2.strides()[0] == mat2_sizes[1]) ||
           (scalar_type != at::ScalarType::Half &&
            scalar_type != at::ScalarType::BFloat16));
#endif
    }
#endif
    if (!useLtInterface) {
      self_ = expand_size(self, {mat1_sizes[0], mat2_sizes[1]}, "addmm");
    }
    self__sizes = self_->sizes();
  } else {
#if defined(USE_ROCM)
    useLtInterface = !disable_addmm_cuda_lt &&
        result.dim() == 2 && result.is_contiguous() &&
        isSupportedHipLtROCmArch(self.device().index()) &&
        (scalar_type == at::ScalarType::Float ||
          scalar_type == at::ScalarType::Half ||
          scalar_type == at::ScalarType::BFloat16);
#endif
    self_ = c10::MaybeOwned<Tensor>::borrowed(self);
    self__sizes = self_->sizes();
    TORCH_CHECK(result.dim() == 2, "tensors must be 2-D");
    TORCH_CHECK(self__sizes[0] == mat1_sizes[0], "self_ dim 0 must match mat1 dim 0");
    TORCH_CHECK(self__sizes[1] == mat2_sizes[1], "self_ dim 1 must match mat2 dim 1");
  }

  if (&result != &self) {
    at::native::resize_output(result, {mat1_sizes[0], mat2_sizes[1]});
    if (beta.toComplexDouble() != 0.0 && !useLtInterface) {
      at::native::copy_(result, *self_);
    }
  }


  IntArrayRef result_sizes = result.sizes();
  if ((result_sizes[0] == 0) || (result_sizes[1] == 0)) {
    return result;
  }

  cublasCommonArgs args(mat1, mat2, result);

  if (mat1.numel() == 0) {
    // By definition, when beta==0, values in self should be ignored. nans and infs
    // should not propagate
    if (beta.toComplexDouble() == 0.) {
      return result.zero_();
    }
    // TODO: We could squeeze some perf by calling at::cuda::mul_out here instead, to bypass the dispatcher.
    // That requires some fixing some internal build dependencies though.
    return at::mul_out(
        result,
        self.expand(result.sizes()),
        at::native::scalar_tensor(
            beta,
            self.scalar_type(),
            std::nullopt /* layout */,
            at::kCPU,
            std::nullopt /* pin_memory */));
  }

  TORCH_INTERNAL_ASSERT_DEBUG_ONLY(!args.result->is_conj());

  if (useLtInterface) {
#if defined(USE_ROCM)
    AT_DISPATCH_FLOATING_TYPES_AND2(
        at::ScalarType::Half,
        at::ScalarType::BFloat16,
        scalar_type,
        "addmm_cuda_lt",
        [&] {
        auto tuning_ctx = at::cuda::tunable::getTuningContext();
        if (tuning_ctx->IsTunableOpEnabled()) {
          launchTunableGemmAndBias<scalar_t>(
              args,
              alpha,
              (&result != &self) ? self.const_data_ptr<scalar_t>() : nullptr,
              activation_to_gemm_and_blas_arg(activation));
        }
        else {
          at::cuda::blas::gemm_and_bias<scalar_t>(
              args.transa == 't',
              args.transb == 't',
              args.m,
              args.n,
              args.k,
              alpha.to<at::opmath_type<scalar_t>>(),
              args.mata->const_data_ptr<scalar_t>(),
              args.lda,
              args.matb->const_data_ptr<scalar_t>(),
              args.ldb,
              // This condition is needed for mm case on ROCm for hipblasLt path.
              // Passing the bias ptr as null to avoid accuracy issues for mm case.
              (&result != &self) ? self.const_data_ptr<scalar_t>() : nullptr,
              args.result->data_ptr<scalar_t>(),
              args.result_ld,
              activation_to_gemm_and_blas_arg(activation)
          );
        }});
#else
    auto activation_epilogue = activation_to_gemm_and_blas_arg(activation);
#if (defined(CUDA_VERSION) && (CUDA_VERSION < 11080))
    // GELU is not supported (and does not compile!) prior
    // to CUDA 11.4. Have observed accuracy issues with
    // GELU epilogue in 11.4; disabling the GELU epilogue
    // path for CUDA version < 11.8.
    if (activation == Activation::GELU)
      activation_epilogue = cuda::blas::GEMMAndBiasActivationEpilogue::None;
#endif

    AT_DISPATCH_FLOATING_TYPES_AND2(
        at::ScalarType::Half,
        at::ScalarType::BFloat16,
        scalar_type,
        "addmm_cuda_lt",
        [&] {
        auto tuning_ctx = at::cuda::tunable::getTuningContext();
        if (tuning_ctx->IsTunableOpEnabled()) {
          launchTunableGemmAndBias<scalar_t>(
              args,
              alpha,
              self.const_data_ptr<scalar_t>(),
              activation_epilogue);
        }
        else {
          at::cuda::blas::gemm_and_bias<scalar_t>(
              args.transa == 't',
              args.transb == 't',
              args.m,
              args.n,
              args.k,
              alpha.to<at::opmath_type<scalar_t>>(),
              args.mata->const_data_ptr<scalar_t>(),
              args.lda,
              args.matb->const_data_ptr<scalar_t>(),
              args.ldb,
              self.const_data_ptr<scalar_t>(),
              args.result->data_ptr<scalar_t>(),
              args.result_ld,
              activation_epilogue
          );
        }});
#endif
  } else
  {
    AT_DISPATCH_FLOATING_AND_COMPLEX_TYPES_AND2(
        at::ScalarType::Half,
        at::ScalarType::BFloat16,
        scalar_type,
        "addmm_cuda",
        [&] {
          using opmath_t = at::opmath_type<scalar_t>;
          opmath_t alpha_val = alpha.to<opmath_t>();
          opmath_t beta_val = beta.to<opmath_t>();
          const scalar_t* mat1_ptr = args.mata->const_data_ptr<scalar_t>();
          const scalar_t* mat2_ptr = args.matb->const_data_ptr<scalar_t>();
          scalar_t* result_ptr = args.result->mutable_data_ptr<scalar_t>();
          at::cuda::blas::gemm<scalar_t>(
              args.transa,
              args.transb,
              args.m,
              args.n,
              args.k,
              alpha_val,
              mat1_ptr,
              args.lda,
              mat2_ptr,
              args.ldb,
              beta_val,
              result_ptr,
              args.result_ld);
        });
    switch (activation) {
      case Activation::RELU:
        at::relu_(const_cast<Tensor&>(*args.result));
        break;
      case Activation::GELU:
        at::gelu_(const_cast<Tensor&>(*args.result), "tanh");
        break;
      default: break;
    }
  }

// Preprocessor gate here needs to match the inverse of the check
// gating activation_to_gemm_and_blas_arg above; here we are manually
// performing a post-GELU because we weren't able to use the GELU
// epilogue above.
#if !(defined(CUDA_VERSION) && CUDA_VERSION >= 11080) && !defined(USE_ROCM)
  if (useLtInterface && activation == Activation::GELU) {
    at::gelu_(const_cast<Tensor&>(*args.result), "tanh");
  }
#endif

  if (!result.is_same(*args.result)) {
    result.copy_(*args.result);
  }
  return result;
}

const Tensor& baddbmm_out_cuda_impl(const Tensor& result, const Tensor& self, const Tensor& batch1, const Tensor& batch2, const Scalar& beta, const Scalar& alpha) {
  // handle pathological cases that blas may not like
  if (result.numel() == 0) {
    return result;
  } else if (batch1.size(2) == 0) {
    if (beta.to<c10::complex<double>>() == 0.0) {
      return result.zero_();
    } else {
      return result.mul_(beta);
    }
  }

  bool transpose_result = false;
  c10::MaybeOwned<Tensor> result_;
  IntArrayRef result_strides = result.strides();
  IntArrayRef result_sizes = result.sizes();

  if ((result_strides[1] == 1) &&
      ((result_sizes[2] == 1) || (result_strides[2] >= std::max<int64_t>(1, result_sizes[1])))) {
    result_ = resolve_conj_if_indicated(result, true);
  } else if ((result_strides[2] == 1) &&
    (result_sizes[1] == 1 || (result_strides[1] >= std::max<int64_t>(1, result_sizes[2])))) {
    transpose_result = true;
    result_ = resolve_conj_if_indicated(result, true);
  } else {
    result_ = c10::MaybeOwned<Tensor>::owned(result.transpose(1, 2).clone(at::MemoryFormat::Contiguous).transpose(1, 2));
  }

  int leading_dim = transpose_result ? 1 : 2;

  int64_t m = result_sizes[transpose_result ? 2 : 1];
  int64_t n = result_sizes[leading_dim];
  int64_t k = (transpose_result ? batch2 : batch1).sizes()[leading_dim];

  int64_t lda, ldb, ldc;
  bool transpose_batch1, transpose_batch2;
  auto batch1_ = prepare_batch_matrix_for_cublas(transpose_result ? batch2 : batch1, transpose_batch1, lda, transpose_result, m, k);
  auto batch2_ = prepare_batch_matrix_for_cublas(transpose_result ? batch1 : batch2, transpose_batch2, ldb, transpose_result, k, n);

  ldc = result_->strides()[leading_dim];
  int64_t num_batches = result_->sizes()[0];

  TORCH_INTERNAL_ASSERT_DEBUG_ONLY(!result_->is_conj());

  AT_DISPATCH_FLOATING_AND_COMPLEX_TYPES_AND2(at::ScalarType::Half, at::ScalarType::BFloat16, self.scalar_type(), "baddbmm_cuda", [&] {
    using opmath_t = at::opmath_type<scalar_t>;
    opmath_t alpha_val = alpha.to<opmath_t>();
    opmath_t beta_val = beta.to<opmath_t>();
    const scalar_t* batch1_ptr = batch1_->const_data_ptr<scalar_t>();
    const scalar_t* batch2_ptr = batch2_->const_data_ptr<scalar_t>();
    scalar_t* result_ptr = result_->mutable_data_ptr<scalar_t>();
    const auto transa = transpose_batch1 ? batch1_->is_conj() ? 'c' : 't' : 'n';
    const auto transb = transpose_batch2 ? batch2_->is_conj() ? 'c' : 't' : 'n';
    // If batch is 1 call gemm rather than bgemm
    if (num_batches == 1) {
      at::cuda::blas::gemm<scalar_t>(
          transa, transb,
          m, n, k,
          alpha_val,
          batch1_ptr, lda,
          batch2_ptr, ldb,
          beta_val,
          result_ptr, ldc);
    } else {
      at::cuda::blas::bgemm<scalar_t>(
        transa, transb,
        m, n, k,
        alpha_val,
        batch1_ptr, lda, batch1_->strides()[0],
        batch2_ptr, ldb, batch2_->strides()[0],
        beta_val,
        result_ptr, ldc, result_->strides()[0],
        num_batches
      );
   }
  });
  if (!result.is_same(*result_)) {
    result.copy_(*result_);
  }
  return result;
}

} // anonymous namespace

TORCH_IMPL_FUNC(addmm_out_cuda)(const Tensor& self, const Tensor& mat1, const Tensor& mat2, const Scalar& beta, const Scalar& alpha, const Tensor& result) {
  addmm_out_cuda_impl(const_cast<Tensor&>(result), self, mat1, mat2, beta, alpha);
}

TORCH_IMPL_FUNC(addmm_activation_out_cuda)(const Tensor& self, const Tensor& mat1, const Tensor& mat2, const Scalar& beta, const Scalar& alpha, bool use_gelu, const Tensor& result) {
  addmm_out_cuda_impl(const_cast<Tensor&>(result), self, mat1, mat2, beta, alpha, use_gelu ? Activation::GELU : Activation::RELU);
}

TORCH_IMPL_FUNC(mm_out_cuda)(const Tensor& self, const Tensor& mat2, const Tensor& result) {
  addmm_out_cuda_impl(const_cast<Tensor&>(result), result, self, mat2, 0, 1);
}

TORCH_IMPL_FUNC(baddbmm_out_cuda)(const Tensor& self, const Tensor& batch1, const Tensor& batch2, const Scalar& beta, const Scalar& alpha, const Tensor& result) {
  {
    at::NoNamesGuard guard;
    baddbmm_out_cuda_impl(result, self, batch1, batch2, beta, alpha);
  }
}

TORCH_IMPL_FUNC(bmm_out_cuda)(const Tensor& batch1, const Tensor& batch2, const Tensor &result) {
  Scalar beta(0.0);
  Scalar alpha(1.0);
  {
    NoNamesGuard guard;
    baddbmm_out_cuda_impl(result, result, batch1, batch2, beta, alpha);
  }
}

namespace {

inline void dot_check(const Tensor& self, const Tensor& other) {
  TORCH_CHECK(
      self.dim() == 1 && other.dim() == 1,
      "1D tensors expected, but got ",
      self.dim(),
      "D and ",
      other.dim(),
      "D tensors");
  TORCH_CHECK(
      self.scalar_type() == other.scalar_type(),
      "dot : expected both vectors to have same dtype, but found ",
      self.scalar_type(),
      " and ",
      other.scalar_type());
  TORCH_CHECK(
      self.numel() == other.numel(),
      "inconsistent tensor size, expected tensor [",
      self.numel(),
      "] and src [",
      other.numel(),
      "] to have the same number of elements, but got ",
      self.numel(),
      " and ",
      other.numel(),
      " elements respectively");
  TORCH_CHECK(
      (self.numel() <= INT_MAX) && (self.stride(0) <= INT_MAX) &&
          (other.stride(0) <= INT_MAX),
      "dot only supports n, incx, incy with the bound [val] <= %d",
      INT_MAX);
}

} // anonymous namespace

Tensor dot_cuda(const Tensor& self, const Tensor& other) {
  if (self.is_complex()) {
    if (self.is_conj()) {
      if (other.is_conj()) {
        return (dot_cuda(self.conj(), other.conj())).conj();
       } else {
         return vdot_cuda(self.conj(), other);
       }
    } else if (other.is_conj()) {
      return vdot_cuda(other.conj(), self);
    }
  }

  at::NoNamesGuard guard;
  dot_check(self, other);

  const int n = static_cast<int>(self.numel());
  int incx = static_cast<int>(self.stride(0));
  int incy = static_cast<int>(other.stride(0));
  if (n == 1) {
    incx = 1;
    incy = 1;
  }

if (self._is_zerotensor() || other._is_zerotensor()) {
  return at::_efficientzerotensor({}, self.options());
}

return AT_DISPATCH_FLOATING_AND_COMPLEX_TYPES_AND2(
      ScalarType::Half, ScalarType::BFloat16,
      self.scalar_type(), "dot",
      [&] {
        Tensor result = at::empty({}, self.options());

        auto handle = at::cuda::getCurrentCUDABlasHandle();
        at::cuda::blas::PointerModeGuard pointerModeGuard(handle, CUBLAS_POINTER_MODE_DEVICE);
        at::cuda::blas::dot<scalar_t>(
            handle,
            n,
            self.const_data_ptr<scalar_t>(),
            incx,
            other.const_data_ptr<scalar_t>(),
            incy,
            result.mutable_data_ptr<scalar_t>());

        return result;
      });
}

Tensor vdot_cuda(const Tensor& self, const Tensor& other) {
  if (!self.is_complex()) {
    return dot_cuda(self, other);
  }

  if (self.is_conj()) {
    if (other.is_conj()) {
      return vdot_cuda(other.conj(), self.conj());
    } else {
      return dot_cuda(self.conj(), other);
    }
  } else if (other.is_conj()) {
    return (dot_cuda(self, other.conj())).conj();
  }

  at::NoNamesGuard guard;
  dot_check(self, other);

  if (self._is_zerotensor() || other._is_zerotensor()) {
    return at::_efficientzerotensor({}, self.options());
  }

  const int n = static_cast<int>(self.numel());
  int incx = static_cast<int>(self.stride(0));
  int incy = static_cast<int>(other.stride(0));
  if (n == 1) {
    incx = 1;
    incy = 1;
  }

  return AT_DISPATCH_COMPLEX_TYPES(self.scalar_type(), "vdot", [&] {
    Tensor result = at::empty({}, self.options());

    auto handle = at::cuda::getCurrentCUDABlasHandle();
    at::cuda::blas::PointerModeGuard pointerModeGuard(
        handle, CUBLAS_POINTER_MODE_DEVICE);
    at::cuda::blas::vdot<scalar_t>(
        handle,
        n,
        self.const_data_ptr<scalar_t>(),
        incx,
        other.const_data_ptr<scalar_t>(),
        incy,
        result.mutable_data_ptr<scalar_t>());

    return result;
  });
}

TORCH_IMPL_FUNC(addmv_out_cuda)(const Tensor &self, const Tensor &mat, const Tensor &vec, const Scalar& beta_, const Scalar& alpha_, const Tensor& result) {
  c10::MaybeOwned<Tensor> self_ = expand_size(self, {mat.size(0)});
  auto betaval = beta_.toComplexDouble();
  if (mat.numel() == 0) {
    // shortcut for an empty matrix
    // By definition, when beta==0, values in self should be ignored. nans and infs
    // should not propagate
    if (betaval == 0.0) {
      result.zero_();
    } else {
      at::mul_out(
          const_cast<Tensor&>(result),
          self,
          at::native::scalar_tensor(
              beta_, self.scalar_type(), std::nullopt /* layout */, at::kCPU, std::nullopt /* pin_memory */));
    }
  } else {
    if (!result.is_same(*self_) && betaval != 0.0) { //if beta is 0, result contents will be zeroed later
      at::native::copy_(const_cast<Tensor&>(result), *self_);
    }
    if (result.numel() != 0) {
      auto r_stride = result.stride(0);
      auto vec_stride = vec.stride(0);

      // Check for contiguity of `vec` and update `vec_stride` accordingly
      const auto vec_contiguous = vec_stride == 0 ? vec.contiguous() : vec;
      // A vector can be contiguous and have a stride of zero if it has it is of length 1
      vec_stride = std::max<int64_t>(vec_contiguous.stride(0), 1LL);

      AT_DISPATCH_FLOATING_AND_COMPLEX_TYPES_AND2(at::ScalarType::Half, at::ScalarType::BFloat16, mat.scalar_type(), "addmv_impl_cuda", [&] {
        auto beta = beta_.to<scalar_t>();
        auto alpha = alpha_.to<scalar_t>();
        if (mat.stride(0) == 1 && mat.stride(1) >= std::max<int64_t>(1, mat.size(0))) {
          at::cuda::blas::gemv<scalar_t>('n',
            mat.size(0), mat.size(1), alpha, mat.const_data_ptr<scalar_t>(), mat.stride(1), vec_contiguous.const_data_ptr<scalar_t>(),
            vec_stride, beta, result.mutable_data_ptr<scalar_t>(), r_stride);
        }
        else if (mat.stride(1) == 1 && mat.stride(0) >= std::max<int64_t>(1, mat.size(1))) {
          at::cuda::blas::gemv<scalar_t>('t',
            mat.size(1), mat.size(0), alpha, mat.const_data_ptr<scalar_t>(), mat.stride(0),
            vec_contiguous.const_data_ptr<scalar_t>(), vec_stride, beta, result.mutable_data_ptr<scalar_t>(), r_stride);
        }
        else {
          Tensor cmat = mat.contiguous();
          at::cuda::blas::gemv<scalar_t>('t',
              mat.size(1), mat.size(0), alpha, cmat.const_data_ptr<scalar_t>(), cmat.stride(0),
              vec_contiguous.const_data_ptr<scalar_t>(), vec_stride, beta, result.mutable_data_ptr<scalar_t>(), r_stride);
        }
      });
    }
  }
}

Tensor& _int_mm_out_cuda(const Tensor& self, const Tensor& mat2, Tensor& result) {
  // NOTE: cuBLAS is currently broken for some combination of transposed inputs.
  TORCH_CHECK(self.dim() == 2, "Expected self to be of dimension 2 but got ", self.dim());
  TORCH_CHECK(mat2.dim() == 2, "Expected mat2 to be of dimension 2 but got ", mat2.dim());
  TORCH_CHECK(self.size(0) > 16, "self.size(0) needs to be greater than 16, but got ", self.size(0));
  TORCH_CHECK(self.size(1) > 0 && self.size(1) % 8 == 0, "self.size(1) needs to be greater than 0 and a multiple of 8, but got ", self.size(1));
  TORCH_CHECK(self.size(1) == mat2.size(0), "self.size(1) needs to match mat2.size(0) but got ", self.size(1), " and ", mat2.size(0));
  TORCH_CHECK(mat2.size(1) > 0 && mat2.size(1) % 8 == 0, "mat2.size(1) needs to be greater than 0 and a multiple of 8, but got ", mat2.size(1));

  TORCH_CHECK(result.dtype() == at::kInt, "Expected result dtype to be of type kInt but got ", result.dtype());
  TORCH_CHECK(result.size(0) == self.size(0), "Expected result.size(0) to be ", self.size(0), " but got ", result.size(0));
  TORCH_CHECK(result.size(1) == mat2.size(1), "Expected result.size(1) to be ", mat2.size(1), " but got ", result.size(1));

  TORCH_CHECK(result.dim() == 2, "Expected result to be of dimension 2 but got ", result.dim());

  TORCH_CHECK(result.is_contiguous(), "Expected result to be contiguous.");

#if (defined(CUDA_VERSION) && (CUDA_VERSION >= 11070)) || defined(USE_ROCM)
  cublasCommonArgs args(self, mat2, result);

  at::cuda::blas::int8_gemm(
      args.transa == 't',
      args.transb == 't',
      args.m,
      args.n,
      args.k,
      args.mata->data_ptr<int8_t>(),
      args.lda,
      args.matb->data_ptr<int8_t>(),
      args.ldb,
      args.result->data_ptr<int32_t>(),
      args.result_ld);

  if (!result.is_same(*args.result)) {
    result.copy_(*args.result);
  }
#else
#if !defined(USE_ROCM) && defined(CUDA_VERSION)
  TORCH_CHECK(false, "_int_mm_out_cuda not compiled for CUDA ", CUDA_VERSION);
#else
  TORCH_CHECK(false, "_int_mm_out_cuda not compiled for this platform.");
#endif
#endif

  return result;
}

Tensor _int_mm_cuda(const Tensor& self, const Tensor& mat2) {
  Tensor result = at::empty({self.size(0), mat2.size(1)}, self.options().dtype(at::kInt));
  return _int_mm_out_cuda(self, mat2, result);
}

static bool _scaled_mm_allowed_device() {
    auto dprops = at::cuda::getCurrentDeviceProperties();
#ifdef USE_ROCM
    std::string device_arch = dprops->gcnArchName;
    static const std::vector<std::string> archs = {"gfx940", "gfx941", "gfx942"};
    for (std::string arch : archs) {
        size_t substring = device_arch.find(arch);
        if (substring != std::string::npos) {
            return true;
        }
    }
    return false;
#else
    return dprops->major >= 9 || (dprops->major == 8 && dprops->minor == 9);
#endif
}

namespace{

enum class ScalingType {
  TensorWise,
  RowWise,
  Error
};
/*
 * Scaling Type Determination:
 * ---------------------------
 * Conditions and corresponding Scaling Types:
 *
 * - If scale_a.numel() == 1 && scale_b.numel() == 1:
 *   - Returns TensorWise.
 *
 * - Else if scale_a.dim() == 1 && scale_a.size(0) == dim_m && scale_b.size(0) == dim_n:
 *   - Returns RowWise.
 *
 * - Otherwise:
 *   - Returns Error.
 */

// Validates the scale tensors to scaled_mm
// And returns the type of scaling/which kernel to use
ScalingType get_scaling_type(
    const at::Tensor& scale_a,
    const at::Tensor& scale_b,
    int64_t dim_m,
    int64_t dim_n) {
  // Both Per-Tensor and Row-wise scaling expect fp32 tensors
  TORCH_CHECK(
      scale_a.scalar_type() == kFloat && scale_b.scalar_type() == kFloat,
      "Both scale_a and scale_b must be float (fp32) tensors.");

  // Check the singluar scale case for per-tensor scaling
  if (scale_a.numel() == 1 && scale_b.numel() == 1) {
    return ScalingType::TensorWise;
  }

  // For non-TensorWise scaling, enforce 2D input tensors
  TORCH_CHECK(
      scale_a.dim() == 2 && scale_b.dim() == 2,
      "For non-TensorWise scaling, scale tensors must be 2-dimensional, "
      "but got scale_a.dim()=",
      scale_a.dim(),
      " and scale_b.dim()=",
      scale_b.dim());

  // Check for RowWise scaling
  if (scale_a.size(0) == dim_m && scale_a.size(1) == 1 &&
      scale_b.size(0) == 1 && scale_b.size(1) == dim_n) {
#if !defined(USE_ROCM) && !defined(_MSC_VER) || \
    (defined(USE_ROCM) && ROCM_VERSION >= 60000)
    TORCH_CHECK(
        scale_a.is_contiguous() && scale_b.is_contiguous(),
        "Both scale_a and scale_b must be contiguous for RowWise scaling.");
    return ScalingType::RowWise;
#else
    TORCH_CHECK(false, "Per-row scaling is not supported for this platform!");
    return ScalingType::Error;
#endif
  }

  // If we reach here, the input doesn't match any valid scaling type
  TORCH_CHECK(
      false,
      "Invalid scaling configuration. For TensorWise scaling, both scales should be scalar. "
      "For RowWise scaling, scale_a should be (",
      dim_m,
      ", 1) and scale_b should be (1, ",
      dim_n,
      "). "
      "Got scale_a.size()=(",
      scale_a.size(0),
      ", ",
      scale_a.size(1),
      ") and ",
      "scale_b.size()=(",
      scale_b.size(0),
      ", ",
      scale_b.size(1),
      ")");

  return ScalingType::Error;
}

} // namespace

// Computes matrix multiply + bias while applying scaling to input and output matrices and computes amax
// Scales are only applicable when matrices are of Float8 type and assumbed to be equal to 1.0 by default.
// If output matrix type is 16 or 32-bit type, neither scale_result is applied nor amax is computed.
// Known limitations:
//  - Only works if mat1 is row-major and mat2 is column-major
//  - Only works if matrices sizes are divisible by 32
//  - If 1-dimensional tensors are used then scale_a should be size = mat1.size(0)
//    and scale_b should have size = to mat2.size(1)
//  Arguments:
//    - `mat1`: the first operand of the matrix multiply, can be type `torch.float8_e4m3fn` or `torch.float8_e5m2`
//    - `mat2`: the second operand of the matrix multiply, can be type `torch.float8_e4m3fn` or `torch.float8_e5m2`
//    - `bias`: the bias, can be type `torch.float16` or `torch.bfloat16`
//    - `out_dtype`: the output dtype, can either be a float8 or a higher precision floating point type
//    - `scale_a`: a scalar or 1-dimensional tensor with the inverse scale of `mat1`, only needed if `mat1` is a float8 type
//    - `scale_b`: a scalar or 1-dimensional tensor with the inverse scale of `mat2`, only needed if `mat2` is a float8 type
//    - `scale_result`: a scalar tensor with the scale of the output, only utilized if the output is a float8 type
//    - `use_fast_accum`: if true, enables fast float8 accumulation
//    - `out`: a reference to the output tensor

Tensor&
_scaled_mm_out_cuda(const Tensor& mat1, const Tensor& mat2,
          const Tensor& scale_a,
          const Tensor& scale_b,
          const std::optional<at::Tensor>& bias,
          const std::optional<at::Tensor>& scale_result,
          std::optional<c10::ScalarType> out_dtype,
          bool use_fast_accum,
          Tensor& out) {
  // Check sizes
  bool allowed_device = _scaled_mm_allowed_device();
  TORCH_CHECK(allowed_device, "torch._scaled_mm is only supported on CUDA devices with compute capability >= 9.0 or 8.9, or ROCm MI300+");
  TORCH_CHECK(mat1.dim() == 2, "mat1 must be a matrix");
  TORCH_CHECK(mat2.dim() == 2, "mat2 must be a matrix");
  TORCH_CHECK(
      mat1.sizes()[1] == mat2.sizes()[0], "mat1 and mat2 shapes cannot be multiplied (",
      mat1.sizes()[0], "x", mat1.sizes()[1], " and ", mat2.sizes()[0], "x", mat2.sizes()[1], ")");

  // Check what type of scaling we are doing based on inputs
  ScalingType scaling_choice = get_scaling_type(scale_a, scale_b, mat1.size(0), mat2.size(1));
  TORCH_INTERNAL_ASSERT(scaling_choice != ScalingType::Error, "Scaling type not supported");

  TORCH_CHECK(!scale_result || (scale_result->numel() == 1 && scale_result->scalar_type() == kFloat),
       "scale_result must be a float scalar");
  TORCH_CHECK(!bias || bias->numel() == mat2.sizes()[1], "Bias must be size ", mat2.sizes()[1],
       " but got ", bias->numel());
  TORCH_CHECK(
      mat1.sizes()[1] % 16 == 0,
      "Expected trailing dimension of mat1 to be divisible by 16 ",
      "but got mat1 shape: (",
      mat1.sizes()[0],
      "x",
      mat1.sizes()[1],
      ".");
  TORCH_CHECK(mat2.sizes()[0] % 16 == 0 && mat2.sizes()[1] % 16 == 0, "mat2 shape (", mat2.sizes()[0], "x",
       mat2.sizes()[1], " must be divisible by 16");
  // Check types
  TORCH_CHECK(!out_dtype || *out_dtype == out.scalar_type(), "out_dtype must match output matrix type");
  TORCH_CHECK(isFloat8Type(mat1.scalar_type()), "Expected mat1 to be Float8 matrix got ", mat1.scalar_type());
  TORCH_CHECK(isFloat8Type(mat2.scalar_type()), "Expected mat2 to be Float8 matrix got ", mat2.scalar_type());
  // Type restrictions imposed by CuBLASLt as of CUDA-12.1
  TORCH_CHECK(mat1.scalar_type() != ScalarType::Float8_e5m2 || mat2.scalar_type() != ScalarType::Float8_e5m2,
        "Multiplication of two Float8_e5m2 matrices is not supported");
  if (bias) {
    TORCH_CHECK(out.scalar_type() != kFloat, "Bias is not supported when out_dtype is set to Float32");
    TORCH_CHECK(bias->scalar_type() == ScalarType::BFloat16 || bias->scalar_type() == ScalarType::Half,
         "Bias must be either Half or BFloat16, but got ", bias->scalar_type());
    TORCH_CHECK((out.scalar_type() != kFloat && out.scalar_type() != ScalarType::BFloat16) ||
          bias->scalar_type() == ScalarType::BFloat16,
          "Bias must be BFloat16 to compute ", out.scalar_type(), " output, but got ", bias->scalar_type());
    TORCH_CHECK(out.scalar_type() != ScalarType::Half || bias->scalar_type() == ScalarType::Half,
          "Bias must be Float16 to compute ", out.scalar_type(), " output, but got ", bias->scalar_type());
  }
  {
    auto bias_ = bias.value_or(Tensor());
    auto scale_result_ = scale_result.value_or(Tensor());

    TensorArg targs[]{{out, "out", 0}, {mat1, "mat1", 1}, {mat2, "mat2", 2},
                      {bias_, "bias", 3}, {scale_a, "scale_a", 4}, {scale_b, "scale_b", 5},
                      {scale_result_, "scale_result", 6}};
    checkAllSameGPU(__func__, targs);
  }
  // Validation checks have passed lets resize the output to actual size
  IntArrayRef mat1_sizes = mat1.sizes();
  IntArrayRef mat2_sizes = mat2.sizes();
  at::native::resize_output(out, {mat1_sizes[0], mat2_sizes[1]});

  // We are doing row-wise scaling
  if (scaling_choice == ScalingType::RowWise) {
    TORCH_CHECK(out.dtype() == kBFloat16, "Only bf16 high precsion output types are supported for row-wise scaling.");
    at::cuda::detail::f8f8bf16_rowwise(
        mat1,
        mat2,
        scale_a,
        scale_b,
        bias,
        use_fast_accum,
        out);
    return out;
  }

  cublasCommonArgs args(mat1, mat2, out);
  const auto out_dtype_ = args.result->scalar_type();
  TORCH_CHECK(args.transa == 't' && args.transb == 'n', "Only multiplication of row-major and column-major matrices is supported by cuBLASLt");

  // Some scaled_gemms require an amax to populate lets create one here
  Tensor amax = at::empty({0}, mat1.options().dtype(ScalarType::Float));

#ifdef USE_ROCM
  auto tuning_ctx = at::cuda::tunable::getTuningContext();
  if (tuning_ctx->IsTunableOpEnabled()) {
#define TUNABLE_DISPATCH(BLASOP_A, BLASOP_B)                            \
        if (mat1.scalar_type() == ScalarType::Float8_e4m3fnuz) {        \
          if (mat2.scalar_type() == ScalarType::Float8_e4m3fnuz) {      \
            static at::cuda::tunable::ScaledGemmTunableOp<              \
                at::Float8_e4m3fnuz, at::Float8_e4m3fnuz, scalar_t,     \
                BLASOP_A, BLASOP_B> scaledgemm{};                       \
            scaledgemm(&params);                                        \
          }                                                             \
          else if (mat2.scalar_type() == ScalarType::Float8_e5m2fnuz) { \
            static at::cuda::tunable::ScaledGemmTunableOp<              \
                at::Float8_e4m3fnuz, at::Float8_e5m2fnuz, scalar_t,     \
                BLASOP_A, BLASOP_B> scaledgemm{};                       \
            scaledgemm(&params);                                        \
          }                                                             \
        }                                                               \
        else if (mat1.scalar_type() == ScalarType::Float8_e5m2fnuz) {   \
          if (mat2.scalar_type() == ScalarType::Float8_e4m3fnuz) {      \
            static at::cuda::tunable::ScaledGemmTunableOp<              \
                at::Float8_e5m2fnuz, at::Float8_e4m3fnuz, scalar_t,     \
                BLASOP_A, BLASOP_B> scaledgemm{};                       \
            scaledgemm(&params);                                        \
          }                                                             \
          else if (mat2.scalar_type() == ScalarType::Float8_e5m2fnuz) { \
            static at::cuda::tunable::ScaledGemmTunableOp<              \
                at::Float8_e5m2fnuz, at::Float8_e5m2fnuz, scalar_t,     \
                BLASOP_A, BLASOP_B> scaledgemm{};                       \
            scaledgemm(&params);                                        \
          }                                                             \
        }
    AT_DISPATCH_V2(out_dtype_, "_tunable_scaled_gemm", AT_WRAP([&] {
      bool transa_ = ((args.transa != 'n') && (args.transa != 'N'));
      bool transb_ = ((args.transb != 'n') && (args.transb != 'N'));
      at::cuda::tunable::ScaledGemmParams<scalar_t> params;
      params.transa = args.transa;
      params.transb = args.transb;
      params.m = args.m;
      params.n = args.n;
      params.k = args.k;
      params.a = args.mata->data_ptr();
      params.a_scale_ptr = scale_a.data_ptr();
      params.lda = args.lda;
      params.a_dtype = args.mata->scalar_type();
      params.b = args.matb->data_ptr();
      params.b_scale_ptr = scale_b.data_ptr();
      params.ldb = args.ldb;
      params.b_dtype = args.matb->scalar_type();
      params.bias_ptr = bias ? bias->data_ptr(): nullptr;
      params.bias_dtype = bias ? bias->scalar_type() : isFloat8Type(out_dtype_) ? at::ScalarType::Half : out_dtype_;
      params.c = args.result->data_ptr();
      params.c_scale_ptr = scale_result ? scale_result->data_ptr() : nullptr;
      params.ldc = args.result_ld;
      params.c_dtype = out_dtype_;
      params.amax_ptr = amax.data_ptr();
      params.use_fast_accum = use_fast_accum;
      if (transa_ && transb_) {
        TUNABLE_DISPATCH(at::cuda::tunable::BlasOp::T, at::cuda::tunable::BlasOp::T)
      }
      else if (transa_ && !transb_) {
        TUNABLE_DISPATCH(at::cuda::tunable::BlasOp::T, at::cuda::tunable::BlasOp::N)
      }
      else if (!transa_ && transb_) {
        TUNABLE_DISPATCH(at::cuda::tunable::BlasOp::N, at::cuda::tunable::BlasOp::T)
      }
      else if (!transa_ && !transb_) {
        TUNABLE_DISPATCH(at::cuda::tunable::BlasOp::N, at::cuda::tunable::BlasOp::N)
      }
      else {
        TORCH_CHECK(false, "unreachable");
      }
    }),
    kHalf, kBFloat16, kFloat8_e4m3fnuz, kFloat8_e5m2fnuz, AT_EXPAND(AT_FLOATING_TYPES));
#undef TUNABLE_DISPATCH
  }
  else
#endif
  {
#if defined(USE_ROCM) && ROCM_VERSION >= 60200
  // hipBlasLT requires scaleD to be set to something in order to use AMAX
    auto dummy_options = TensorOptions().dtype(kFloat).device(kCUDA);
    auto dummy_scale = at::ones(1, dummy_options);
#endif
    at::cuda::blas::scaled_gemm(
        args.transa,
        args.transb,
        args.m,
        args.n,
        args.k,
        args.mata->data_ptr(),
        scale_a.data_ptr(),
        args.lda,
        args.mata->scalar_type(),
        args.matb->data_ptr(),
        scale_b.data_ptr(),
        args.ldb,
        args.matb->scalar_type(),
        bias ? bias->data_ptr(): nullptr,
        bias ? bias->scalar_type() : isFloat8Type(out_dtype_) ? at::ScalarType::Half : out_dtype_,
        args.result->data_ptr(),
#if defined(USE_ROCM) && ROCM_VERSION >= 60200
        scale_result ? scale_result->data_ptr() : dummy_scale.data_ptr(),
#else
        scale_result ? scale_result->data_ptr() : nullptr,
#endif
        args.result_ld,
        out_dtype_,
        amax.data_ptr(),
        use_fast_accum);
  }

  return out;
}

Tensor
_scaled_mm_cuda(const Tensor& mat_a, const Tensor& mat_b,
          const Tensor& scale_a,
          const Tensor& scale_b,
          const std::optional<at::Tensor>& bias,
          const std::optional<at::Tensor>& scale_result,
          std::optional<c10::ScalarType> out_dtype,
          bool use_fast_accum) {
  const auto out_dtype_ = out_dtype.value_or(mat_a.scalar_type());
  Tensor out = at::empty({0}, mat_a.options().dtype(out_dtype_));
  return _scaled_mm_out_cuda(mat_a, mat_b, scale_a, scale_b, bias, scale_result, out_dtype, use_fast_accum, out);
}

} // namespace at::native