SequenceSlice

#include <popops/SequenceSlice.hpp>

Support for dynamic slices.

namespace poplar

Poplar classes and functions.

namespace popops

Common functions, such as elementwise and reductions.

Functions

void sequenceSlice(poplar::Graph &graph, const poplar::Tensor &tIn, const poplar::Tensor &tOut, const poplar::Tensor &tN, const poplar::Tensor &tInOffset, const poplar::Tensor &tOutOffset, bool zeroUnused, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext = {})

Slice a 2d tensor based on offsets specified by a tensor.

Typically this is used to copy subsequences of one tensor to another. The outermost dimension is sliced; tOut[tOutOffset:tOutOffset+tN][…] = tIn[tInOffset:tInOffset+tN][…] for each entry in tN/tInOffset/tOutOffset; entries after the first tN==0 may be ignored. Unreferenced elements of tOut are zeroed if zeroUnused is set. The same output element should not be written by multiple inputs.

tIn and tOut must have rank >=2. The outer dimension is sliced; the product of the inner dimensions must match. tInOffset, tOutOffset and tN must be 1d and the same size.

Parameters

  • graph – The Poplar graph.

  • tIn – The source tensor.

  • tOut – The destination tensor.

  • tN – The number of elements to copy.

  • tInOffset – First element read from tIn.

  • tOutOffset – First element written in tOut.

  • zeroUnused – Whether to zero unreferenced tOut elements.

  • prog – The program to be extended.

  • debugContext – Optional debug information.