gemm

Computes a sparse matrix times dense matrix product.

Description and Assumptions

Refer to Supported Types for a list of supported <fp> and <intType> types. The oneapi::mkl::sparse::gemm routine computes a sparse matrix-dense matrix product defined as

\[C \leftarrow \alpha \text{op}(A) B + \beta C\]

where \(\alpha\) and \(\beta\) are scalars, \(B\) and \(C\) are dense matrices and \(A\) is a sparse matrix. Dense matrix storage is in row-major format. Sparse matrix formats are compressed sparse row (CSR) formats.

gemm (Buffer version)

Syntax

namespace oneapi::mkl::sparse {

   void gemm (sycl::queue                          &queue,
              oneapi::mkl::transpose               transpose_val,
              const fp                             alpha,
              oneapi::mkl::sparse::matrix_handle_t A_handle,
              sycl::buffer<fp, 1>                  &B,
              const std::int64_t                   columns,
              const std::int64_t                   ldb,
              const fp                             beta,
              sycl::buffer<fp, 1>                  &C,
              const std::int64_t                   ldc);

}

Input parameters

queue

Specifies the SYCL command queue which will be used for SYCL kernels execution.

transpose_val

Specifies operation op() on input matrix. The possible options are described in transpose enum class.

alpha

Specifies the scalar \(\alpha\).

A_handle

Handle to object containing sparse matrix, \(A\). Created using the oneapi::mkl::sparse::set_csr_data routine.

B

The dense matrix in the sparse-dense matrix product. A one dimensional SYCL memory object containing an array of size at least cols*ldb, where cols = the number of columns of matrix \(op(A)\).

columns

Number of columns of matrix, \(C\).

ldb

Specifies the leading dimension of matrix, \(B\). Should be greater than or equal to the number of columns of \(B\) which is columns.

beta

Specifies the scalar beta.

C

The dense matrix input/output array. A one-dimensional SYCL memory object containing an array of size at least rows*ldc, where rows = the number of rows of matrix \(op(A)\).

ldc

Specifies the leading dimension of matrix \(C\) . Must be greater than or equal to the number of columns of \(C\) which is columns.

Output Parameters

C

Dense matrix output is overwritten by the updated matrix, \(C\).

Throws

This routine shall throw the following exceptions if the associated condition is detected. An implementation may throw additional implementation-specific exception(s) in case of error conditions not covered here.

gemm (USM version)

Syntax

namespace oneapi::mkl::sparse {

   sycl::event gemm (sycl::queue                           &queue,
                     oneapi::mkl::transpose                transpose_val,
                     const fp                              alpha,
                     oneapi::mkl::sparse::matrix_handle_t  A_handle,
                     const fp                              *B,
                     const std::int64_t                    columns,
                     const std::int64_t                    ldb,
                     const fp                              beta,
                     const fp                              *C,
                     const std::int64_t                    ldc,
                     const std::vector<sycl::event>        &dependencies = {});

}

Input parameters

queue

Specifies the SYCL command queue which will be used for SYCL kernels execution.

transpose_val

Specifies operation op() on input matrix. The possible options are described in transpose enum class.

alpha

Specifies the scalar \(\alpha\).

A_handle

Handle to object containing sparse matrix, \(A\). Created using the oneapi::mkl::sparse::set_csr_data routine.

B

The dense matrix in the sparse-dense matrix product. A device accessible USM object containing an array of size at least cols*ldb, where cols = the number of columns of matrix \(op(A)\).

columns

Number of columns of matrix \(C\).

ldb

Specifies the leading dimension of matrix \(B\). Should be greater than or equal to the number of columns of \(B\).

beta

Specifies the scalar beta.

C

The dense matrix input/output array. A device accessible USM object containing an array of size at least rows*ldc, where rows = the number of rows of matrix \(op(A)\).

ldc

Specifies the leading dimension of matrix \(C\) . Must be greater than or equal to columns.

dependencies

List of events that oneapi::mkl::sparse::gemm routine depends on. If omitted, defaults to no dependencies.

Output Parameters

C

Dense matrix output is overwritten by the updated matrix \(C\).

Throws

This routine shall throw the following exceptions if the associated condition is detected. An implementation may throw additional implementation-specific exception(s) in case of error conditions not covered here.

Return Values

Output event that can be waited upon or added as a dependency for the completion of gemm routine.