Collectives.hpp File Reference

#include <poplar/DebugContext.hpp>
#include <poplar/Graph.hpp>
#include <poplar/OptionFlags.hpp>
#include <poplar/Program.hpp>
#include <poplar/Tensor.hpp>
#include <iosfwd>
#include <vector>

Go to the source code of this file.

Classes
struct	gcl::CommGroup
	Struct to specify sub-groups of replicas. More...
struct	gcl::Chunk
	Represents a section of a tensor mapped to an IPU. More...
struct	gcl::Chunks
	A vector of Chunk data. More...

Namespaces
namespace	gcl
	Graphcore Communications Library.

Macros
#define	GCL_NO_DISCARD
	Produce compile time warning for unused return values.

Enumerations
enum class	gcl::CommGroupType { gcl::ALL , gcl::CONSECUTIVE , gcl::ORTHOGONAL }
	Enum to define communication group specification type. More...
enum class	gcl::CollectiveOperator { }
	Supported collective operators. More...

Functions
std::istream &	gcl::operator>> (std::istream &is, CollectiveOperator &op)
	Parse token from input stream is to op. More...
std::ostream &	gcl::operator<< (std::ostream &os, const CollectiveOperator &op)
	Write op to output stream os. More...
CrossReplica functions
Collective operations working across replicas.
poplar::Tensor	gcl::allReduceCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform an all-reduce operation. More...
std::vector< poplar::Tensor >	gcl::allReduceCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform an all-reduce operation on multiple tensors. More...
poplar::Tensor	gcl::allReduceCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceCrossReplica() without the group arg (for all replicas). More...
std::vector< poplar::Tensor >	gcl::allReduceCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceCrossReplica() with multiple input tensors and without the group arg. More...
void	gcl::allReduceToDestinationCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::Tensor &destination, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceCrossReplica() but writes the result to the destination tensor. More...
void	gcl::allReduceToDestinationCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, const std::vector< poplar::Tensor > &destinations, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceToDestinationCrossReplica() with multiple input and output tensors. More...
void	gcl::allReduceToDestinationCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::Tensor &destination, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceToDestinationCrossReplica() without group arg. More...
void	gcl::allReduceInPlaceCrossReplica (poplar::Graph &graph, poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceCrossReplica() but writes result back to the input data tensor. More...
void	gcl::allReduceInPlaceCrossReplica (poplar::Graph &graph, std::vector< poplar::Tensor > &datas, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform an all-reduce operation on multiple tensors writing the results back to the input datas tensors. More...
void	gcl::allReduceInPlaceCrossReplica (poplar::Graph &graph, poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceInPlaceCrossReplica() without group arg. More...
void	gcl::allReduceInPlaceCrossReplica (poplar::Graph &graph, std::vector< poplar::Tensor > &datas, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allReduceInPlaceCrossReplica() with multiple input tensors and without group arg. More...
poplar::Tensor	gcl::reduceScatterCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Reduce the replicated rank-1 tensor data with the result scattered across the replicas. More...
std::vector< poplar::Tensor >	gcl::reduceScatterCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As reduceScatterCrossReplica() but with vector input argument and vector output as return value. More...
void	gcl::reduceScatterToDestinationCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, const std::vector< poplar::Tensor > &destinations, CollectiveOperator op, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As reduceScatterCrossReplica() but with vector input/output arguments. More...
poplar::Tensor	gcl::reduceScatterCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As reduceScatterCrossReplica() without group arg. More...
poplar::Tensor	gcl::allGatherCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Gather the replicated tensor data. More...
std::vector< poplar::Tensor >	gcl::allGatherCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allGatherCrossReplica() but with vector input argument and vector output as return value. More...
void	gcl::allGatherToDestinationCrossReplica (poplar::Graph &graph, const std::vector< poplar::Tensor > &datas, const std::vector< poplar::Tensor > &destinations, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allGatherCrossReplica() but with vector input/output arguments. More...
poplar::Tensor	gcl::allGatherCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allGatherCrossReplica() without group arg. More...
poplar::Tensor	gcl::allToAllCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::program::Sequence &prog, const CommGroup &group, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform an all-to-all exchange of the elements of the input tensor based on replica ID. More...
poplar::Tensor	gcl::allToAllCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	As allToAllCrossReplica() without group arg. More...
poplar::Tensor	gcl::broadcastCrossReplica (poplar::Graph &graph, const poplar::Tensor &data, poplar::program::Sequence &prog, const CommGroup &group={}, unsigned rootReplica=0, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform a broadcast from one replica to all other replicas. More...
WithinReplica functions
Collective operations working within replicas.
poplar::Tensor	gcl::concatChunks (const Chunks &chunks)
	Concatenates chunks. More...
Chunks	gcl::reduceScatterWithinReplica (poplar::Graph &graph, const poplar::Tensor &toReduce, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Reduce a rank 2 tensor. More...
poplar::Tensor	gcl::allGatherWithinReplica (poplar::Graph &graph, const Chunks &toGather, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Broadcast data distributed over all IPUs. More...
poplar::Tensor	gcl::allReduceWithinReplica (poplar::Graph &graph, const poplar::Tensor &toReduce, CollectiveOperator op, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext={}, const poplar::OptionFlags &options={})
	Perform an all-reduce operation on the specified tensor. More...