FunASR/funasr/export/models/language_models/transformer.py
2023-07-07 16:53:16 +08:00

111 lines
3.8 KiB
Python

import os
import torch
import torch.nn as nn
from funasr.modules.vgg2l import import VGG2L
from funasr.modules.attention import MultiHeadedAttention
from funasr.modules.subsampling import (
Conv2dSubsampling, Conv2dSubsampling6, Conv2dSubsampling8)
from funasr.export.models.modules.encoder_layer import EncoderLayerConformer as OnnxEncoderLayer
from funasr.export.models.language_models.embed import Embedding
from funasr.export.models.modules.multihead_att import OnnxMultiHeadedAttention
from funasr.export.utils.torch_function import MakePadMask
class TransformerLM(nn.Module, AbsExportModel):
def __init__(self, model, max_seq_len=512, **kwargs):
super().__init__()
self.embed = Embedding(model.embed, max_seq_len)
self.encoder = model.encoder
self.decoder = model.decoder
self.make_pad_mask = MakePadMask(max_seq_len, flip=False)
# replace multihead attention module into customized module.
for i, d in enumerate(self.encoder.encoders):
# d is EncoderLayer
if isinstance(d.self_attn, MultiHeadedAttention):
d.self_attn = OnnxMultiHeadedAttention(d.self_attn)
self.encoder.encoders[i] = OnnxEncoderLayer(d)
self.model_name = "transformer_lm"
self.num_heads = self.encoder.encoders[0].self_attn.h
self.hidden_size = self.encoder.encoders[0].self_attn.linear_out.out_features
def prepare_mask(self, mask):
if len(mask.shape) == 2:
mask = mask[:, None, None, :]
elif len(mask.shape) == 3:
mask = mask[:, None, :]
mask = 1 - mask
return mask * -10000.0
def forward(self, y, cache):
feats_length = torch.ones(y.shape).sum(dim=-1).type(torch.long)
mask = self.make_pad_mask(feats_length) # (B, T)
mask = (y != 0) * mask
xs = self.embed(y)
# forward_one_step of Encoder
if isinstance(
self.encoder.embed,
(Conv2dSubsampling, Conv2dSubsampling6, Conv2dSubsampling8, VGG2L),
):
xs, mask = self.encoder.embed(xs, mask)
else:
xs = self.encoder.embed(xs)
new_cache = []
mask = self.prepare_mask(mask)
for c, e in zip(cache, self.encoder.encoders):
xs, mask = e(xs, mask, c)
new_cache.append(xs)
if self.encoder.normalize_before:
xs = self.encoder.after_norm(xs)
h = self.decoder(xs[:, -1])
return h, new_cache
def get_dummy_inputs(self):
tgt = torch.LongTensor([1]).unsqueeze(0)
cache = [
torch.zeros((1, 1, self.encoder.encoders[0].size))
for _ in range(len(self.encoder.encoders))
]
return (tgt, cache)
def is_optimizable(self):
return True
def get_input_names(self):
return ["tgt"] + ["cache_%d" % i for i in range(len(self.encoder.encoders))]
def get_output_names(self):
return ["y"] + ["out_cache_%d" % i for i in range(len(self.encoder.encoders))]
def get_dynamic_axes(self):
ret = {"tgt": {0: "tgt_batch", 1: "tgt_length"}}
ret.update(
{
"cache_%d" % d: {0: "cache_%d_batch" % d, 1: "cache_%d_length" % d}
for d in range(len(self.encoder.encoders))
}
)
ret.update(
{
"out_cache_%d"
% d: {0: "out_cache_%d_batch" % d, 1: "out_cache_%d_length" % d}
for d in range(len(self.encoder.encoders))
}
)
return ret
def get_model_config(self, path):
return {
"use_lm": True,
"model_path": os.path.join(path, f"{self.model_name}.onnx"),
"lm_type": "TransformerLM",
"odim": self.encoder.encoders[0].size,
"nlayers": len(self.encoder.encoders),
}