/// <summary>
/// Transformer encoder
/// </summary>
/// <param name="rawInputs"></param>
/// <param name="g"></param>
/// <returns></returns>
public IWeightTensor Encode(IWeightTensor rawInput, int batchSize, IComputeGraph g)
{
int seqLen = rawInput.Rows / batchSize;
IWeightTensor posEmbedding = g.BuildPositionMatrix(seqLen, m_inputDim);
IWeightTensor posEmbeddingRepeat = g.RepeatRows(posEmbedding, batchSize, runGradient: false);
// Transpose to batch-first based sequence
IWeightTensor inputs = g.TransposeBatch(rawInput, batchSize);
inputs = g.AddMul(posEmbeddingRepeat, inputs, (float)Math.Sqrt(m_inputDim), runGradientW1: false, runGradientW2: true);
// We don't update position embedding, so dispose it now to save memory.
posEmbeddingRepeat.Dispose();
posEmbedding.Dispose();
inputs = g.Dropout(inputs, batchSize, m_dropoutRatio, inPlace: true);
for (int k = 0; k < m_encoders.Count; k++)
{
inputs = m_encoders[k].Perform(inputs, batchSize, g);
}
// Transpose back to time-first based sequence
rawInput = g.TransposeBatch(inputs, seqLen);
return(rawInput);
}
/// <summary>
/// Transformer encoder
/// </summary>
/// <param name="rawInputs"></param>
/// <param name="g"></param>
/// <returns></returns>
///
public IWeightTensor Decode(IWeightTensor tgtInputs, IWeightTensor encOutputBatchFirst, IWeightTensor tgtSelfMask, IWeightTensor decEncAttnMask, IWeightTensor tgtDimMask, int batchSize, IComputeGraph g)
{
int tgtSeqLen = tgtInputs.Rows / batchSize;
int srcSeqLen = encOutputBatchFirst.Rows / batchSize;
using (IWeightTensor posEmbedding = g.BuildPositionMatrix(tgtSeqLen, m_inputDim))
{
using (IWeightTensor posEmbeddingRepeat = g.RepeatRows(posEmbedding, batchSize, runGradient: false))
{
tgtInputs = g.AddMul(posEmbeddingRepeat, tgtInputs, (float)Math.Sqrt(m_inputDim), runGradientW1: false, runGradientW2: true);
}
}
tgtInputs = g.Dropout(tgtInputs, batchSize, m_dropoutRatio, inPlace: true);
var tgtSelfMaskRep = g.View(tgtSelfMask, dims: new long[] { 1, batchSize, tgtSeqLen, tgtSeqLen });
var tgtSelfMaskRepExp = g.Expand(tgtSelfMaskRep, dims: new long[] { m_multiHeadNum, batchSize, tgtSeqLen, tgtSeqLen });
var decEncAttnMaskRep = g.View(decEncAttnMask, dims: new long[] { 1, batchSize, tgtSeqLen, srcSeqLen });
var decEncAttnMaskRepExp = g.Expand(decEncAttnMaskRep, dims: new long[] { m_multiHeadNum, batchSize, tgtSeqLen, srcSeqLen });
var tgtSelfMaskRepExpView = g.View(tgtSelfMaskRepExp, dims: new long[] { m_multiHeadNum *batchSize *tgtSeqLen, tgtSeqLen });
var decEncAttnMaskRepExpView = g.View(decEncAttnMaskRepExp, dims: new long[] { m_multiHeadNum *batchSize *tgtSeqLen, srcSeqLen });
tgtSelfMaskRep.Dispose();
tgtSelfMaskRepExp.Dispose();
decEncAttnMaskRep.Dispose();
decEncAttnMaskRepExp.Dispose();
using (IComputeGraph subg = g.CreateSubGraph($"{m_name}_Decoder"))
{
for (int k = 0; k < m_selfAttns.Count; k++)
{
tgtInputs = g.MaskFill(tgtInputs, tgtDimMask, 0.0f);
tgtInputs = m_selfAttns[k].Perform(tgtInputs, tgtInputs, tgtInputs, tgtSelfMaskRepExpView, batchSize, subg);
tgtInputs = m_encAttns[k].Perform(tgtInputs, encOutputBatchFirst, encOutputBatchFirst, decEncAttnMaskRepExpView, batchSize, subg);
tgtInputs = m_posFFNs[k].Perform(tgtInputs, batchSize, subg);
}
tgtInputs.UnbindFromComputeGraph();
}
tgtInputs = layerNorm.Norm(tgtInputs, g);
// tgtInputs = m_decoderFFLayer.Process(tgtInputs, batchSize, g);
return(tgtInputs);
}
/// <summary>
/// Transformer encoder
/// </summary>
/// <param name="rawInputs"></param>
/// <param name="g"></param>
/// <returns></returns>
public IWeightTensor Encode(IWeightTensor inputs, IWeightTensor selfMask, IWeightTensor dimMask, int batchSize, IComputeGraph g)
{
int seqLen = inputs.Rows / batchSize;
using (IWeightTensor posEmbedding = g.BuildPositionMatrix(seqLen, m_inputDim))
{
using (IWeightTensor posEmbeddingRepeat = g.RepeatRows(posEmbedding, batchSize, runGradient: false))
{
inputs = g.AddMul(posEmbeddingRepeat, inputs, (float)Math.Sqrt(m_inputDim), runGradientW1: false, runGradientW2: true);
}
}
inputs = g.Dropout(inputs, batchSize, m_dropoutRatio, inPlace: true);
var selfMaskRep = g.View(selfMask, dims: new long[] { 1, batchSize, seqLen, seqLen });
var multiHeadhSelfMaskRep = g.Expand(selfMaskRep, dims: new long[] { m_multiHeadNum, batchSize, seqLen, seqLen });
var multiHeadhSelfMaskRepView = g.View(multiHeadhSelfMaskRep, dims: new long[] { m_multiHeadNum *batchSize *seqLen, seqLen });
selfMaskRep.Dispose();
multiHeadhSelfMaskRep.Dispose();
using (IComputeGraph subg = g.CreateSubGraph($"{m_name}_Encoder"))
{
for (int k = 0; k < m_encoders.Count; k++)
{
inputs = g.MaskFill(inputs, dimMask, 0.0f);
inputs = m_encoders[k].Perform(inputs, inputs, inputs, multiHeadhSelfMaskRepView, batchSize, subg);
inputs = m_posFFNs[k].Perform(inputs, batchSize, subg);
}
inputs.UnbindFromComputeGraph();
}
inputs = layerNorm.Norm(inputs, g);
return(inputs);
}