diff --git "a/modeling_t5.py" "b/modeling_t5.py" new file mode 100644--- /dev/null +++ "b/modeling_t5.py" @@ -0,0 +1,2220 @@ +# coding=utf-8 +# Copyright 2018 Mesh TensorFlow authors, T5 Authors and HuggingFace Inc. team. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the language governing permissions and +# limitations under the License. +"""This code is adapted from the T5 code on the Huggingface Transformers library.""" +""" PyTorch GLM T5 model.""" + + +import copy +import math +import os +import warnings +from typing import Optional, Tuple, Union +import logging + +import torch +from torch import nn +from torch.nn import CrossEntropyLoss +from torch.utils.checkpoint import checkpoint + +from transformers.activations import ACT2FN +from transformers.modeling_outputs import ( + BaseModelOutput, + BaseModelOutputWithPastAndCrossAttentions, + Seq2SeqLMOutput, + Seq2SeqModelOutput, +) +from transformers.modeling_utils import PreTrainedModel +from transformers.pytorch_utils import ALL_LAYERNORM_LAYERS, find_pruneable_heads_and_indices, prune_linear_layer +from transformers.utils import ( + DUMMY_INPUTS, + DUMMY_MASK, + add_start_docstrings, + add_start_docstrings_to_model_forward, + is_torch_fx_proxy, + replace_return_docstrings, +) +from transformers.utils import logging as transformers_logging +from transformers.utils.model_parallel_utils import assert_device_map, get_device_map +from .configuration_t5 import T5Config +from .wrapper_functions import DataProcessor + + +logger = transformers_logging.get_logger(__name__) + +_CONFIG_FOR_DOC = "T5Config" +_CHECKPOINT_FOR_DOC = "t5-small" + +#################################################### +# This dict contains ids and associated url +# for the pretrained weights provided with the models +#################################################### +T5_PRETRAINED_MODEL_ARCHIVE_LIST = [ + "t5-small", + "t5-base", + "t5-large", + "t5-3b", + "t5-11b", + # See all T5 models at https://huggingface.co/models?filter=t5 +] + + +#################################################### +# This is a conversion method from TF 1.0 to PyTorch +# More details: https://medium.com/huggingface/from-tensorflow-to-pytorch-265f40ef2a28 +#################################################### +def load_tf_weights_in_t5(model, config, tf_checkpoint_path): + """Load tf checkpoints in a pytorch model.""" + raise NotImplementedError("NOT TESTED; might need adjustments for GLM") + try: + import re + + import numpy as np + import tensorflow as tf + except ImportError: + logger.error( + "Loading a TensorFlow model in PyTorch, requires TensorFlow to be installed. Please see " + "https://www.tensorflow.org/install/ for installation instructions." + ) + raise + tf_path = os.path.abspath(tf_checkpoint_path) + logger.info(f"Converting TensorFlow checkpoint from {tf_path}") + # Load weights from TF model + init_vars = tf.train.list_variables(tf_path) + names = [] + tf_weights = {} + for name, shape in init_vars: + logger.info(f"Loading TF weight {name} with shape {shape}") + array = tf.train.load_variable(tf_path, name) + names.append(name) + tf_weights[name] = array + + for txt_name in names: + name = txt_name.split("/") + # adam_v and adam_m are variables used in AdamWeightDecayOptimizer to calculated m and v + # which are not required for using pretrained model + if any( + n in ["adam_v", "adam_m", "AdamWeightDecayOptimizer", "AdamWeightDecayOptimizer_1", "global_step"] + for n in name + ): + logger.info(f"Skipping {'/'.join(name)}") + tf_weights.pop(txt_name, None) + continue + if "_slot_" in name[-1]: + logger.info(f"Skipping {'/'.join(name)}") + tf_weights.pop(txt_name, None) + continue + pointer = model + array = tf_weights[txt_name] + + for m_name in name: + if re.fullmatch(r"[A-Za-z]+_\d+", m_name): + scope_names = re.split(r"_(\d+)", m_name) + else: + scope_names = [m_name] + if scope_names[0] in ["kernel", "scale", "embedding"]: + pointer = getattr(pointer, "weight") + elif scope_names[0] == "self_attention": + pointer = getattr(pointer, "layer") + pointer = pointer[0] + elif scope_names[0] == "enc_dec_attention": + pointer = getattr(pointer, "layer") + pointer = pointer[1] + elif scope_names[0] == "dense_relu_dense": + pointer = getattr(pointer, "layer") + pointer = pointer[2] + elif scope_names[0] == "rms_norm": + if hasattr(pointer, "layer_norm"): + pointer = getattr(pointer, "layer_norm") + elif hasattr(pointer, "final_layer_norm"): + pointer = getattr(pointer, "final_layer_norm") + elif scope_names[0] == "scale": + pointer = getattr(pointer, "weight") + elif scope_names[0] == "output_bias" or scope_names[0] == "beta": + pointer = getattr(pointer, "bias") + elif scope_names[0] == "squad": + pointer = getattr(pointer, "classifier") + elif scope_names[0] == "decoder" and name[1] == "logits": + continue + elif scope_names[0] == "logits": + pointer = getattr(pointer, "lm_head") + elif scope_names[0] == "wi" and len(scope_names) > 1 and scope_names[1].isdigit(): + pointer = getattr(pointer, f"wi_{scope_names[1]}") + continue + else: + try: + pointer = getattr(pointer, scope_names[0]) + except AttributeError: + logger.info(f"Skipping {'/'.join(name)}") + continue + if len(scope_names) >= 2: + num = int(scope_names[1]) + pointer = pointer[num] + if scope_names[0] not in ["kernel", "scale", "embedding"]: + pointer = getattr(pointer, "weight") + if scope_names[0] != "embedding": + logger.info(f"Transposing numpy weight of shape {array.shape} for {name}") + array = np.transpose(array) + try: + assert ( + pointer.shape == array.shape + ), f"Pointer shape {pointer.shape} and array shape {array.shape} mismatched" + except AssertionError as e: + e.args += (pointer.shape, array.shape) + raise + logger.info(f"Initialize PyTorch weight {name}") + pointer.data = torch.from_numpy(array.astype(np.float32)) + tf_weights.pop(txt_name, None) + + logger.info(f"Weights not copied to PyTorch model: {', '.join(tf_weights.keys())}.") + return model + + +#################################################### +# PyTorch Models are constructed by sub-classing +# - torch.nn.Module for the layers and +# - PreTrainedModel for the models (it-self a sub-class of nn.Module) +#################################################### +PARALLELIZE_DOCSTRING = r""" + This is an experimental feature and is a subject to change at a moment's notice. + + Uses a device map to distribute attention modules of the model across several devices. If no device map is given, + it will evenly distribute blocks across all devices. + + Args: + device_map (`Dict[int, list]`, optional, defaults to None): + A dictionary that maps attention modules to devices. Note that the embedding module and LMHead are always + automatically mapped to the first device (for esoteric reasons). That means that the first device should + have fewer attention modules mapped to it than other devices. For reference, the t5 models have the + following number of attention modules: + + - t5-small: 6 + - t5-base: 12 + - t5-large: 24 + - t5-3b: 24 + - t5-11b: 24 + + Example: + + ```python + # Here is an example of a device map on a machine with 4 GPUs using t5-3b, which has a total of 24 attention modules: + model = T5ForConditionalGeneration.from_pretrained("t5-3b") + device_map = { + 0: [0, 1, 2], + 1: [3, 4, 5, 6, 7, 8, 9], + 2: [10, 11, 12, 13, 14, 15, 16], + 3: [17, 18, 19, 20, 21, 22, 23], + } + model.parallelize(device_map) + ``` +""" +DEPARALLELIZE_DOCSTRING = r""" + Moves the model to cpu from a model parallel state. + + Example: + + ```python + # On a 4 GPU machine with t5-3b: + model = T5ForConditionalGeneration.from_pretrained("t5-3b") + device_map = { + 0: [0, 1, 2], + 1: [3, 4, 5, 6, 7, 8, 9], + 2: [10, 11, 12, 13, 14, 15, 16], + 3: [17, 18, 19, 20, 21, 22, 23], + } + model.parallelize(device_map) # Splits the model across several devices + model.deparallelize() # Put the model back on cpu and cleans memory by calling torch.cuda.empty_cache() + ``` +""" + + +class T5LayerNorm(nn.Module): + def __init__(self, hidden_size, eps=1e-6): + """ + Construct a layernorm module in the T5 style. No bias and no subtraction of mean. + """ + super().__init__() + self.weight = nn.Parameter(torch.ones(hidden_size)) + self.variance_epsilon = eps + + def forward(self, hidden_states): + # T5 uses a layer_norm which only scales and doesn't shift, which is also known as Root Mean + # Square Layer Normalization https://arxiv.org/abs/1910.07467 thus varience is calculated + # w/o mean and there is no bias. Additionally we want to make sure that the accumulation for + # half-precision inputs is done in fp32 + + variance = hidden_states.to(torch.float32).pow(2).mean(-1, keepdim=True) + hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon) + + # convert into half-precision if necessary + if self.weight.dtype in [torch.float16, torch.bfloat16]: + hidden_states = hidden_states.to(self.weight.dtype) + + return self.weight * hidden_states + + + +# try: +# from apex.normalization import FusedRMSNorm + +# T5LayerNorm = FusedRMSNorm # noqa + +# logger.info("Discovered apex.normalization.FusedRMSNorm - will use it instead of T5LayerNorm") +# except ImportError: +# # using the normal T5LayerNorm +# pass +# except Exception: +# logger.warning("discovered apex but it failed to load, falling back to T5LayerNorm") +# pass + +ALL_LAYERNORM_LAYERS.append(T5LayerNorm) + + +class T5DenseActDense(nn.Module): + def __init__(self, config: T5Config): + super().__init__() + self.wi = nn.Linear(config.d_model, config.d_ff, bias=False) + self.wo = nn.Linear(config.d_ff, config.d_model, bias=False) + self.dropout = nn.Dropout(config.dropout_rate) + self.act = ACT2FN[config.dense_act_fn] + + def forward(self, hidden_states): + hidden_states = self.wi(hidden_states) + hidden_states = self.act(hidden_states) + hidden_states = self.dropout(hidden_states) + if ( + isinstance(self.wo.weight, torch.Tensor) + and hidden_states.dtype != self.wo.weight.dtype + and self.wo.weight.dtype != torch.int8 + ): + hidden_states = hidden_states.to(self.wo.weight.dtype) + hidden_states = self.wo(hidden_states) + return hidden_states + + +class T5DenseGatedActDense(nn.Module): + def __init__(self, config: T5Config): + super().__init__() + self.wi_0 = nn.Linear(config.d_model, config.d_ff, bias=False) + self.wi_1 = nn.Linear(config.d_model, config.d_ff, bias=False) + self.wo = nn.Linear(config.d_ff, config.d_model, bias=False) + self.dropout = nn.Dropout(config.dropout_rate) + self.act = ACT2FN[config.dense_act_fn] + + def forward(self, hidden_states): + hidden_gelu = self.act(self.wi_0(hidden_states)) + hidden_linear = self.wi_1(hidden_states) + hidden_states = hidden_gelu * hidden_linear + hidden_states = self.dropout(hidden_states) + + # To make 8bit quantization work for google/flan-t5-xxl, self.wo is kept in float32. + # See https://github.com/huggingface/transformers/issues/20287 + # we also make sure the weights are not in `int8` in case users will force `_keep_in_fp32_modules` to be `None`` + if ( + isinstance(self.wo.weight, torch.Tensor) + and hidden_states.dtype != self.wo.weight.dtype + and self.wo.weight.dtype != torch.int8 + ): + hidden_states = hidden_states.to(self.wo.weight.dtype) + + hidden_states = self.wo(hidden_states) + return hidden_states + + +class T5LayerFF(nn.Module): + def __init__(self, config: T5Config): + super().__init__() + if config.is_gated_act: + self.DenseReluDense = T5DenseGatedActDense(config) + else: + self.DenseReluDense = T5DenseActDense(config) + + self.layer_norm = T5LayerNorm(config.d_model, eps=config.layer_norm_epsilon) + self.dropout = nn.Dropout(config.dropout_rate) + + def forward(self, hidden_states): + forwarded_states = self.layer_norm(hidden_states) + forwarded_states = self.DenseReluDense(forwarded_states) + hidden_states = hidden_states + self.dropout(forwarded_states) + return hidden_states + + +class T5Attention(nn.Module): + def __init__(self, config: T5Config, has_relative_attention_bias=False): + super().__init__() + self.is_decoder = config.is_decoder + self.has_relative_attention_bias = has_relative_attention_bias + + self.relative_attention_num_buckets = config.relative_attention_num_buckets + self.relative_attention_num_additional_buckets = config.relative_attention_num_additional_buckets if 'relative_attention_num_additional_buckets' in config.__dict__.keys() else 0 + self.relative_attention_max_distance = config.relative_attention_max_distance + self.d_model = config.d_model + self.key_value_proj_dim = config.d_kv + self.n_heads = config.num_heads + self.dropout = config.dropout_rate + self.inner_dim = self.n_heads * self.key_value_proj_dim + + # Mesh TensorFlow initialization to avoid scaling before softmax + self.q = nn.Linear(self.d_model, self.inner_dim, bias=False) + self.k = nn.Linear(self.d_model, self.inner_dim, bias=False) + self.v = nn.Linear(self.d_model, self.inner_dim, bias=False) + self.o = nn.Linear(self.inner_dim, self.d_model, bias=False) + + if self.has_relative_attention_bias: + if self.is_decoder: + num_buckets = self.relative_attention_num_buckets + else: + num_buckets = self.relative_attention_num_buckets + self.relative_attention_num_additional_buckets + self.relative_attention_bias = nn.Embedding(num_buckets, self.n_heads) + self.pruned_heads = set() + self.gradient_checkpointing = False + + def prune_heads(self, heads): + if len(heads) == 0: + return + heads, index = find_pruneable_heads_and_indices( + heads, self.n_heads, self.key_value_proj_dim, self.pruned_heads + ) + # Prune linear layers + self.q = prune_linear_layer(self.q, index) + self.k = prune_linear_layer(self.k, index) + self.v = prune_linear_layer(self.v, index) + self.o = prune_linear_layer(self.o, index, dim=1) + # Update hyper params + self.n_heads = self.n_heads - len(heads) + self.inner_dim = self.key_value_proj_dim * self.n_heads + self.pruned_heads = self.pruned_heads.union(heads) + + @staticmethod + def _og_relative_position_bucket(relative_position, bidirectional=True, num_buckets=32, max_distance=128): + """ + This is the original implementation from T5 which will be called below. + + Adapted from Mesh Tensorflow: + https://github.com/tensorflow/mesh/blob/0cb87fe07da627bf0b7e60475d59f95ed6b5be3d/mesh_tensorflow/transformer/transformer_layers.py#L593 + + Translate relative position to a bucket number for relative attention. The relative position is defined as + memory_position - query_position, i.e. the distance in tokens from the attending position to the attended-to + position. If bidirectional=False, then positive relative positions are invalid. We use smaller buckets for + small absolute relative_position and larger buckets for larger absolute relative_positions. All relative + positions >=max_distance map to the same bucket. All relative positions <=-max_distance map to the same bucket. + This should allow for more graceful generalization to longer sequences than the model has been trained on + + Args: + relative_position: an int32 Tensor + bidirectional: a boolean - whether the attention is bidirectional + num_buckets: an integer + max_distance: an integer + + Returns: + a Tensor with the same shape as relative_position, containing int32 values in the range [0, num_buckets) + """ + relative_buckets = 0 + + if bidirectional: + num_buckets //= 2 + relative_buckets += (relative_position > 0).to(torch.long) * num_buckets + relative_position = torch.abs(relative_position) + else: + relative_position = -torch.min(relative_position, torch.zeros_like(relative_position)) + # now relative_position is in the range [0, inf) + + # half of the buckets are for exact increments in positions + max_exact = num_buckets // 2 + is_small = relative_position < max_exact + + # The other half of the buckets are for logarithmically bigger bins in positions up to max_distance + relative_position_if_large = max_exact + ( + torch.log(relative_position.float() / max_exact) + / math.log(max_distance / max_exact) + * (num_buckets - max_exact) + ).to(torch.long) + relative_position_if_large = torch.min( + relative_position_if_large, torch.full_like(relative_position_if_large, num_buckets - 1) + ) + + relative_buckets += torch.where(is_small, relative_position, relative_position_if_large) + return relative_buckets + + @staticmethod + def _relative_position_bucket(relative_position, bidirectional=True, num_buckets=32, max_distance=128, use_additional_bucket=None): + """ + This function is a wrapper for _og_relative_position_bucket. It allows for additional buckets to be added via use_additional_bucket, which is a bool tensor of the same shape as relative_position. Entries where use_additional_bucket is False use the usual conventional buckets from relative_position. Entries where use_additional_bucket is True use the additional buckets. The additional buckets are added to the end of the bucket list, so the first additional bucket will be bucket `num_buckets`, the second will be `num_buckets + 1` and so on. Which one of the additional buckets is used depends on the value of relative_position. So if relative_position is 5, and use_additional_bucket is True, then the bucket used will be `num_buckets + 5`. If relative_position is 5, and use_additional_bucket is False, then the bucket corresponding to a relative position of 5 will be used. The standard relative PE buckets have indices in the range [0, num_buckets), so an entry of `0` in relative_position will use the first additional bucket if use_additional_bucket is True. Entries to relative_position where use_relative_PE is True should be non-negative intergers. Entries where use_relative_PE is False can be any integer. + + The additional buckets can be used to encode relative positions such as Graph to Graph for long-ranged connections (e.g. in the global GLM), Graph to Text, or Text to Graph. + + If use_additional_bucket is None (or a Tensor where all entries are False), then this function is equivalent to _relative_position_bucket + + Note that the embeddings are not initialized automatically when additional buckets are used, so they need to be initialized manually. This can be done by calling init_relative_position_bias. + + Params: + use_additional_bucket: a Tensor with the same shape as relative_position and type torch.bool + Returns: + a Tensor with the same shape as relative_position, containing int32 values in the range [0, num_buckets + max(relative_position[use_additional_bucket]) + 1) + """ + + relative_buckets = T5Attention._og_relative_position_bucket(relative_position, bidirectional, num_buckets, max_distance) + + if use_additional_bucket is None: + return relative_buckets + + relative_buckets[use_additional_bucket] = relative_position[use_additional_bucket] + num_buckets + + return relative_buckets + + def compute_bias(self, query_length, key_length, device=None, relative_position=None, use_additional_bucket=None): + """Compute binned relative position bias + :param relative_position: [MP] torch.long tensor in shape [query_length, key_length] + """ + if device is None: + device = self.relative_attention_bias.weight.device + + if relative_position is None: + context_position = torch.arange(query_length, dtype=torch.long, device=device)[:, None] + memory_position = torch.arange(key_length, dtype=torch.long, device=device)[None, :] + relative_position = memory_position - context_position # shape (query_length, key_length) + else: + assert relative_position.dtype == torch.long, f"{relative_position.dtype} should be torch.long" + assert relative_position.device == device, f"{relative_position.device} should be {device}" + # relative_position = relative_position.to(device) + + relative_position_bucket = self._relative_position_bucket( + relative_position, # shape (query_length, key_length) + bidirectional=(not self.is_decoder), + num_buckets=self.relative_attention_num_buckets, + max_distance=self.relative_attention_max_distance, + use_additional_bucket=use_additional_bucket, + ) + + values = self.relative_attention_bias(relative_position_bucket) # shape (query_length, key_length, num_heads) + + values = values.permute([2, 0, 1]).unsqueeze(0) # shape (query_length, key_length) # [MP] actually the shape is (1, num_heads, query_length, key_length) + + return values + + def forward( + self, + hidden_states, + mask=None, + key_value_states=None, + position_bias=None, + past_key_value=None, + layer_head_mask=None, + query_length=None, + use_cache=False, + output_attentions=False, + relative_position=None, + sparsity_mask=None, + use_additional_bucket=None, + ): + """ + Self-attention (if key_value_states is None) or attention over source sentence (provided by key_value_states). + + :param relative_position: [MP] relative position for the attention. If `None`, it will be computed as in a standard sequence-to-sequence model. If not `None`, it will be used as the relative position for the attention. It is a tensor of shape [batch_size, query_length, key_length]. + :param sparsity_mask: [MP] sparsity mask for the attention. If `None`, it will be computed as in a standard sequence-to-sequence model. If not `None`, it will be used as the sparsity mask for the attention. It is a tensor of shape [batch_size, query_length, key_length]. A value of 1 means that the corresponding attention weight is not masked, and a value of 0 means that the corresponding attention weight is masked. Hence, the sparsity mask is a binary mask that (kind of) can be used like a multiplicative mask. + :param use_additional_bucket: [MP] whether to use additional buckets for the attention. If `None`, only standard positional encodings will be used. If not `None`, additional buckets will be used for the relative position. It is a tensor of shape [batch_size, query_length, key_length]. A value of False means that the corresponding position is a standard relative position, and a value of True means that the corresponding additional bucket should be used. + """ + # Input is (batch_size, seq_length, dim) + # Mask is (batch_size, key_length) (non-causal) or (batch_size, key_length, key_length) + # past_key_value[0] is (batch_size, n_heads, q_len - 1, dim_per_head) + batch_size, seq_length = hidden_states.shape[:2] + + real_seq_length = seq_length + + if past_key_value is not None: + assert ( + len(past_key_value) == 2 + ), f"past_key_value should have 2 past states: keys and values. Got { len(past_key_value)} past states" + real_seq_length += past_key_value[0].shape[2] if query_length is None else query_length + + key_length = real_seq_length if key_value_states is None else key_value_states.shape[1] + + def shape(states): + """projection""" + return states.view(batch_size, -1, self.n_heads, self.key_value_proj_dim).transpose(1, 2) + + def unshape(states): + """reshape""" + return states.transpose(1, 2).contiguous().view(batch_size, -1, self.inner_dim) + + def project(hidden_states, proj_layer, key_value_states, past_key_value): + """projects hidden states correctly to key/query states""" + if key_value_states is None: + # self-attn + # (batch_size, n_heads, seq_length, dim_per_head) + hidden_states = shape(proj_layer(hidden_states)) + elif past_key_value is None: + # cross-attn + # (batch_size, n_heads, seq_length, dim_per_head) + hidden_states = shape(proj_layer(key_value_states)) + + if past_key_value is not None: + if key_value_states is None: + # self-attn + # (batch_size, n_heads, key_length, dim_per_head) + hidden_states = torch.cat([past_key_value, hidden_states], dim=2) + elif past_key_value.shape[2] != key_value_states.shape[1]: + # checking that the `sequence_length` of the `past_key_value` is the same as + # the provided `key_value_states` to support prefix tuning + # cross-attn + # (batch_size, n_heads, seq_length, dim_per_head) + hidden_states = shape(proj_layer(key_value_states)) + else: + # cross-attn + hidden_states = past_key_value + return hidden_states + + # get query states + query_states = shape(self.q(hidden_states)) # (batch_size, n_heads, seq_length, dim_per_head) + + # get key/value states + key_states = project( + hidden_states, self.k, key_value_states, past_key_value[0] if past_key_value is not None else None + ) + value_states = project( + hidden_states, self.v, key_value_states, past_key_value[1] if past_key_value is not None else None + ) + + # compute scores + scores = torch.matmul( + query_states, key_states.transpose(3, 2) + ) # equivalent of torch.einsum("bnqd,bnkd->bnqk", query_states, key_states), compatible with onnx op>9 + + if position_bias is None: + if not self.has_relative_attention_bias: + position_bias = torch.zeros( + (1, self.n_heads, real_seq_length, key_length), device=scores.device, dtype=scores.dtype + ) + if self.gradient_checkpointing and self.training: + position_bias.requires_grad = True + else: + if relative_position is None: + assert use_additional_bucket is None + position_bias = self.compute_bias(real_seq_length, key_length, device=scores.device, use_additional_bucket=None) + # position_bias = torch.cat(tuple(position_bias for _ in range(batch_size)), dim=0) + else: + position_bias = torch.cat(tuple(self.compute_bias(real_seq_length, key_length, device=scores.device, relative_position=r, use_additional_bucket=u) for r, u in zip(relative_position, use_additional_bucket)), dim=0) + + # if key and values are already calculated + # we want only the last query position bias + if past_key_value is not None: + position_bias = position_bias[:, :, -hidden_states.size(1) :, :] + + logging.debug(f"position_bias = {position_bias.shape if position_bias is not None else position_bias}") + logging.debug(f"mask = {mask.shape if mask is not None else mask}") + if mask is not None: + position_bias = position_bias + mask # (batch_size, n_heads, seq_length, key_length) + + if self.pruned_heads: + mask = torch.ones(position_bias.shape[1]) + mask[list(self.pruned_heads)] = 0 + position_bias_masked = position_bias[:, mask.bool()] + else: + position_bias_masked = position_bias + + if sparsity_mask is not None: + assert sparsity_mask.dtype == torch.bool, f"{relative_position.dtype} should be torch.bool" + + sparsity_mask = ~ sparsity_mask.unsqueeze(1) # add extra dimension for heads and negate for indexing the masked positions + sparsity_mask = sparsity_mask.expand_as(position_bias_masked) + + scores += position_bias_masked + + # >>> masked softmax >>> + if sparsity_mask is not None: + scores[sparsity_mask] = float('-inf') # this works in the backward pass, because potential nan values that the softmax produces in the forward pass are not used in backpropagation, because the "=" is independent of the value that the entry had previously. This is not the case for "+=", which is why we need to set the values to -inf instead of adding -inf. + + # (batch_size, n_heads, seq_length, key_length) + attn_weights = nn.functional.softmax(scores.float(), dim=-1).type_as( + scores + ) # (batch_size, n_heads, seq_length, key_length) + + # replace nan values in the attention weights with 0. nan happens if all positions are masked for one token, as then all inputs to softmax are -inf for that token + attn_weights = torch.nan_to_num(attn_weights, nan=0.0) + # <<< masked softmax <<< + + attn_weights = nn.functional.dropout( + attn_weights, p=self.dropout, training=self.training + ) # (batch_size, n_heads, seq_length, key_length) + + # Mask heads if we want to + if layer_head_mask is not None: + attn_weights = attn_weights * layer_head_mask + + attn_output = unshape(torch.matmul(attn_weights, value_states)) # (batch_size, seq_length, dim) + attn_output = self.o(attn_output) + + present_key_value_state = (key_states, value_states) if (self.is_decoder and use_cache) else None + outputs = (attn_output,) + (present_key_value_state,) + (position_bias,) + + if output_attentions: + outputs = outputs + (attn_weights,) + return outputs + + def init_relative_position_bias(self, modelsize:str, is_decoder:bool=False, init_additional_buckets_from:list[int]=None): + """ + Initializes parameters for relative position bias. This is necessary, if additional buckets are used, as then the weights are not initialized automatically when calling `from_pretrained`. + :param modelsize: the model size of the model from which the relative position bias should be inherited + :param is_decoder: whether the SelfAttention is in the decoder or not. This determines whether the relative position bias is initialized from the parents encoder or decoder. + :param init_additional_buckets_from: the indices of the buckets from which the additional buckets should be initialized. If this is an int, then all additional buckets are initialized from the same bucket. If this is a list, then the list should have the same length as the number of additional buckets, and the i-th entry of the list determines from which bucket the i-th additional bucket is initialized. Setting this to None (or an element in the list to None) means that the additional bucket is not initialized, i.e. it is left unchanged. + """ + if self.is_decoder: + raise NotImplementedError("Decoder is not tested.") + + logging.debug('Loading model from which relative position bias should be inherited') + parent_model = T5EncoderModel.from_pretrained(modelsize) # Needs to be changed for decoder support + + logging.debug('Get relative position bias from parent model') + if is_decoder: + parent_bias = parent_model.decoder.block[0].layer[0].SelfAttention.relative_attention_bias.weight + else: + parent_bias = parent_model.encoder.block[0].layer[0].SelfAttention.relative_attention_bias.weight + del parent_model # free memory + + assert parent_bias.shape[1] == self.relative_attention_bias.weight.shape[1], f"{parent_bias.shape[1]} should be {self.relative_attention_bias.weight.shape[1]}" + assert parent_bias.shape[0] <= self.relative_attention_bias.weight.shape[0], f"{parent_bias.shape[0]} should be <= {self.relative_attention_bias.weight.shape[0]}" + + logging.debug('init normal buckets') + with torch.no_grad(): + self.relative_attention_bias.weight[:parent_bias.shape[0], :] = parent_bias + + logging.debug('get parent buckets for additional buckets') + if init_additional_buckets_from is None: + return + num_additional_buckets = self.relative_attention_bias.weight.shape[0] - parent_bias.shape[0] + if num_additional_buckets == 0: + return + if not isinstance(init_additional_buckets_from, list): + init_additional_buckets_from = [init_additional_buckets_from]*num_additional_buckets + assert len(init_additional_buckets_from) == num_additional_buckets, f"{len(init_additional_buckets_from)} should be {num_additional_buckets}" + + skip_bucket = [idx is None for idx in init_additional_buckets_from] + init_additional_buckets_from = [0 if idx is None else idx for idx in init_additional_buckets_from] + init_additional_buckets_from = torch.tensor(init_additional_buckets_from, dtype=torch.long) + init_additional_buckets_from = self._relative_position_bucket(relative_position=init_additional_buckets_from, bidirectional=(not is_decoder), num_buckets=self.relative_attention_num_buckets, max_distance=self.relative_attention_max_distance, use_additional_bucket=None) + + logging.debug('Initialize relative position bias') + with torch.no_grad(): + for i, (skip, idx) in enumerate(zip(skip_bucket, init_additional_buckets_from), start=parent_bias.shape[0]): + if skip: + continue + self.relative_attention_bias.weight[i, :] = parent_bias[idx, :] + + +class T5LayerSelfAttention(nn.Module): + def __init__(self, config, has_relative_attention_bias=False): + super().__init__() + self.SelfAttention = T5Attention(config, has_relative_attention_bias=has_relative_attention_bias) + self.layer_norm = T5LayerNorm(config.d_model, eps=config.layer_norm_epsilon) + self.dropout = nn.Dropout(config.dropout_rate) + + def forward( + self, + hidden_states, + attention_mask=None, + position_bias=None, + layer_head_mask=None, + past_key_value=None, + use_cache=False, + output_attentions=False, + relative_position=None, + sparsity_mask=None, + use_additional_bucket=None, + ): + logging.debug('### SelfAttention ###') + normed_hidden_states = self.layer_norm(hidden_states) + attention_output = self.SelfAttention( + normed_hidden_states, + mask=attention_mask, + position_bias=position_bias, + layer_head_mask=layer_head_mask, + past_key_value=past_key_value, + use_cache=use_cache, + output_attentions=output_attentions, + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + hidden_states = hidden_states + self.dropout(attention_output[0]) + outputs = (hidden_states,) + attention_output[1:] # add attentions if we output them + return outputs + + +class T5LayerCrossAttention(nn.Module): + def __init__(self, config): + raise NotImplementedError("might need adjustments for GLM") + super().__init__() + self.EncDecAttention = T5Attention(config, has_relative_attention_bias=False) + self.layer_norm = T5LayerNorm(config.d_model, eps=config.layer_norm_epsilon) + self.dropout = nn.Dropout(config.dropout_rate) + + def forward( + self, + hidden_states, + key_value_states, + attention_mask=None, + position_bias=None, + layer_head_mask=None, + past_key_value=None, + use_cache=False, + query_length=None, + output_attentions=False, + ): + logging.debug('### CrossAttention ###') + normed_hidden_states = self.layer_norm(hidden_states) + attention_output = self.EncDecAttention( + normed_hidden_states, + mask=attention_mask, + key_value_states=key_value_states, + position_bias=position_bias, + layer_head_mask=layer_head_mask, + past_key_value=past_key_value, + use_cache=use_cache, + query_length=query_length, + output_attentions=output_attentions, + ) + layer_output = hidden_states + self.dropout(attention_output[0]) + outputs = (layer_output,) + attention_output[1:] # add attentions if we output them + return outputs + + +class T5Block(nn.Module): + def __init__(self, config, has_relative_attention_bias=False): + super().__init__() + self.is_decoder = config.is_decoder + self.layer = nn.ModuleList() + self.layer.append(T5LayerSelfAttention(config, has_relative_attention_bias=has_relative_attention_bias)) + if self.is_decoder: + self.layer.append(T5LayerCrossAttention(config)) + + self.layer.append(T5LayerFF(config)) + + def forward( + self, + hidden_states, + attention_mask=None, + position_bias=None, + encoder_hidden_states=None, + encoder_attention_mask=None, + encoder_decoder_position_bias=None, + layer_head_mask=None, + cross_attn_layer_head_mask=None, + past_key_value=None, + use_cache=False, + output_attentions=False, + return_dict=True, + relative_position=None, + sparsity_mask=None, + use_additional_bucket=None, + ): + if past_key_value is not None: + if not self.is_decoder: + logger.warning("`past_key_values` is passed to the encoder. Please make sure this is intended.") + expected_num_past_key_values = 2 if encoder_hidden_states is None else 4 + + if len(past_key_value) != expected_num_past_key_values: + raise ValueError( + f"There should be {expected_num_past_key_values} past states. " + f"{'2 (past / key) for cross attention. ' if expected_num_past_key_values == 4 else ''}" + f"Got {len(past_key_value)} past key / value states" + ) + + self_attn_past_key_value = past_key_value[:2] + cross_attn_past_key_value = past_key_value[2:] + else: + self_attn_past_key_value, cross_attn_past_key_value = None, None + + self_attention_outputs = self.layer[0]( + hidden_states, + attention_mask=attention_mask, + position_bias=position_bias, + layer_head_mask=layer_head_mask, + past_key_value=self_attn_past_key_value, + use_cache=use_cache, + output_attentions=output_attentions, + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + hidden_states, present_key_value_state = self_attention_outputs[:2] + attention_outputs = self_attention_outputs[2:] # Keep self-attention outputs and relative position weights + + # clamp inf values to enable fp16 training + if hidden_states.dtype == torch.float16 and torch.isinf(hidden_states).any(): + clamp_value = torch.finfo(hidden_states.dtype).max - 1000 + hidden_states = torch.clamp(hidden_states, min=-clamp_value, max=clamp_value) + + do_cross_attention = self.is_decoder and encoder_hidden_states is not None + if do_cross_attention: + # the actual query length is unknown for cross attention + # if using past key value states. Need to inject it here + if present_key_value_state is not None: + query_length = present_key_value_state[0].shape[2] + else: + query_length = None + + cross_attention_outputs = self.layer[1]( + hidden_states, + key_value_states=encoder_hidden_states, + attention_mask=encoder_attention_mask, + position_bias=encoder_decoder_position_bias, + layer_head_mask=cross_attn_layer_head_mask, + past_key_value=cross_attn_past_key_value, + query_length=query_length, + use_cache=use_cache, + output_attentions=output_attentions, + ) + hidden_states = cross_attention_outputs[0] + + # clamp inf values to enable fp16 training + if hidden_states.dtype == torch.float16 and torch.isinf(hidden_states).any(): + clamp_value = torch.finfo(hidden_states.dtype).max - 1000 + hidden_states = torch.clamp(hidden_states, min=-clamp_value, max=clamp_value) + + # Combine self attn and cross attn key value states + if present_key_value_state is not None: + present_key_value_state = present_key_value_state + cross_attention_outputs[1] + + # Keep cross-attention outputs and relative position weights + attention_outputs = attention_outputs + cross_attention_outputs[2:] + + # Apply Feed Forward layer + hidden_states = self.layer[-1](hidden_states) + + # clamp inf values to enable fp16 training + if hidden_states.dtype == torch.float16 and torch.isinf(hidden_states).any(): + clamp_value = torch.finfo(hidden_states.dtype).max - 1000 + hidden_states = torch.clamp(hidden_states, min=-clamp_value, max=clamp_value) + + outputs = (hidden_states,) + + if use_cache: + outputs = outputs + (present_key_value_state,) + attention_outputs + else: + outputs = outputs + attention_outputs + + return outputs # hidden-states, present_key_value_states, (self-attention position bias), (self-attention weights), (cross-attention position bias), (cross-attention weights) + + +class T5PreTrainedModel(PreTrainedModel): + """ + An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained + models. + """ + + config_class = T5Config + load_tf_weights = load_tf_weights_in_t5 + base_model_prefix = "transformer" + is_parallelizable = True + supports_gradient_checkpointing = True + _no_split_modules = ["T5Block"] + _keep_in_fp32_modules = ["wo"] + data_processor = DataProcessor + + @property + def dummy_inputs(self): + input_ids = torch.tensor(DUMMY_INPUTS) + input_mask = torch.tensor(DUMMY_MASK) + dummy_inputs = { + "decoder_input_ids": input_ids, + "input_ids": input_ids, + "decoder_attention_mask": input_mask, + } + return dummy_inputs + + def _init_weights(self, module): + """Initialize the weights""" + factor = self.config.initializer_factor # Used for testing weights initialization + if isinstance(module, T5LayerNorm): + module.weight.data.fill_(factor * 1.0) + elif isinstance(module, (T5Model, T5ForConditionalGeneration, T5EncoderModel)): + # Mesh TensorFlow embeddings initialization + # See https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/layers.py#L1624 + module.shared.weight.data.normal_(mean=0.0, std=factor * 1.0) + if hasattr(module, "lm_head") and not self.config.tie_word_embeddings: + module.lm_head.weight.data.normal_(mean=0.0, std=factor * 1.0) + elif isinstance(module, T5DenseActDense): + # Mesh TensorFlow FF initialization + # See https://github.com/tensorflow/mesh/blob/master/mesh_tensorflow/transformer/transformer_layers.py#L56 + # and https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/layers.py#L89 + module.wi.weight.data.normal_(mean=0.0, std=factor * ((self.config.d_model) ** -0.5)) + if hasattr(module.wi, "bias") and module.wi.bias is not None: + module.wi.bias.data.zero_() + module.wo.weight.data.normal_(mean=0.0, std=factor * ((self.config.d_ff) ** -0.5)) + if hasattr(module.wo, "bias") and module.wo.bias is not None: + module.wo.bias.data.zero_() + elif isinstance(module, T5DenseGatedActDense): + module.wi_0.weight.data.normal_(mean=0.0, std=factor * ((self.config.d_model) ** -0.5)) + if hasattr(module.wi_0, "bias") and module.wi_0.bias is not None: + module.wi_0.bias.data.zero_() + module.wi_1.weight.data.normal_(mean=0.0, std=factor * ((self.config.d_model) ** -0.5)) + if hasattr(module.wi_1, "bias") and module.wi_1.bias is not None: + module.wi_1.bias.data.zero_() + module.wo.weight.data.normal_(mean=0.0, std=factor * ((self.config.d_ff) ** -0.5)) + if hasattr(module.wo, "bias") and module.wo.bias is not None: + module.wo.bias.data.zero_() + elif isinstance(module, T5Attention): + # Mesh TensorFlow attention initialization to avoid scaling before softmax + # See https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/transformer/attention.py#L136 + d_model = self.config.d_model + key_value_proj_dim = self.config.d_kv + n_heads = self.config.num_heads + module.q.weight.data.normal_(mean=0.0, std=factor * ((d_model * key_value_proj_dim) ** -0.5)) + module.k.weight.data.normal_(mean=0.0, std=factor * (d_model**-0.5)) + module.v.weight.data.normal_(mean=0.0, std=factor * (d_model**-0.5)) + module.o.weight.data.normal_(mean=0.0, std=factor * ((n_heads * key_value_proj_dim) ** -0.5)) + if module.has_relative_attention_bias: + module.relative_attention_bias.weight.data.normal_(mean=0.0, std=factor * ((d_model) ** -0.5)) + + def _set_gradient_checkpointing(self, module, value=False): + if isinstance(module, (T5Attention, T5Stack)): + module.gradient_checkpointing = value + + def _shift_right(self, input_ids): + decoder_start_token_id = self.config.decoder_start_token_id + pad_token_id = self.config.pad_token_id + + assert decoder_start_token_id is not None, ( + "self.model.config.decoder_start_token_id has to be defined. In T5 it is usually set to the pad_token_id." + " See T5 docs for more information" + ) + + # shift inputs to the right + if is_torch_fx_proxy(input_ids): + # Item assignment is not supported natively for proxies. + shifted_input_ids = torch.full(input_ids.shape[:-1] + (1,), decoder_start_token_id) + shifted_input_ids = torch.cat([shifted_input_ids, input_ids[..., :-1]], dim=-1) + else: + shifted_input_ids = input_ids.new_zeros(input_ids.shape) + shifted_input_ids[..., 1:] = input_ids[..., :-1].clone() + shifted_input_ids[..., 0] = decoder_start_token_id + + assert pad_token_id is not None, "self.model.config.pad_token_id has to be defined." + # replace possible -100 values in labels by `pad_token_id` + shifted_input_ids.masked_fill_(shifted_input_ids == -100, pad_token_id) + + return shifted_input_ids + + +class T5Stack(T5PreTrainedModel): + def __init__(self, config, embed_tokens=None): + super().__init__(config) + + self.embed_tokens = embed_tokens + self.is_decoder = config.is_decoder + + self.block = nn.ModuleList( + [T5Block(config, has_relative_attention_bias=bool(i == 0)) for i in range(config.num_layers)] + ) + self.final_layer_norm = T5LayerNorm(config.d_model, eps=config.layer_norm_epsilon) + self.dropout = nn.Dropout(config.dropout_rate) + + # Initialize weights and apply final processing + self.post_init() + # Model parallel + self.model_parallel = False + self.device_map = None + self.gradient_checkpointing = False + + @add_start_docstrings(PARALLELIZE_DOCSTRING) + def parallelize(self, device_map=None): + warnings.warn( + "`T5Stack.parallelize` is deprecated and will be removed in v5 of Transformers, you should load your model" + " with `device_map='balanced'` in the call to `from_pretrained`. You can also provide your own" + " `device_map` but it needs to be a dictionary module_name to device, so for instance {'block.0': 0," + " 'block.1': 1, ...}", + FutureWarning, + ) + # Check validity of device_map + self.device_map = ( + get_device_map(len(self.block), range(torch.cuda.device_count())) if device_map is None else device_map + ) + assert_device_map(self.device_map, len(self.block)) + self.model_parallel = True + self.first_device = "cpu" if "cpu" in self.device_map.keys() else "cuda:" + str(min(self.device_map.keys())) + self.last_device = "cuda:" + str(max(self.device_map.keys())) + # Load onto devices + for k, v in self.device_map.items(): + for layer in v: + cuda_device = "cuda:" + str(k) + self.block[layer] = self.block[layer].to(cuda_device) + + # Set embed_tokens to first layer + self.embed_tokens = self.embed_tokens.to(self.first_device) + # Set final layer norm to last device + self.final_layer_norm = self.final_layer_norm.to(self.last_device) + + @add_start_docstrings(DEPARALLELIZE_DOCSTRING) + def deparallelize(self): + warnings.warn( + "Like `parallelize`, `deparallelize` is deprecated and will be removed in v5 of Transformers.", + FutureWarning, + ) + self.model_parallel = False + self.device_map = None + self.first_device = "cpu" + self.last_device = "cpu" + for i in range(len(self.block)): + self.block[i] = self.block[i].to("cpu") + self.embed_tokens = self.embed_tokens.to("cpu") + self.final_layer_norm = self.final_layer_norm.to("cpu") + torch.cuda.empty_cache() + + def get_input_embeddings(self): + return self.embed_tokens + + def set_input_embeddings(self, new_embeddings): + self.embed_tokens = new_embeddings + + def forward( + self, + input_ids=None, + attention_mask=None, + encoder_hidden_states=None, + encoder_attention_mask=None, + inputs_embeds=None, + head_mask=None, + cross_attn_head_mask=None, + past_key_values=None, + use_cache=None, + output_attentions=None, + output_hidden_states=None, + return_dict=None, + relative_position=None, + sparsity_mask=None, + use_additional_bucket=None, + ): + # Model parallel + if self.model_parallel: + torch.cuda.set_device(self.first_device) + self.embed_tokens = self.embed_tokens.to(self.first_device) + use_cache = use_cache if use_cache is not None else self.config.use_cache + output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions + output_hidden_states = ( + output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states + ) + return_dict = return_dict if return_dict is not None else self.config.use_return_dict + + if input_ids is not None and inputs_embeds is not None: + err_msg_prefix = "decoder_" if self.is_decoder else "" + raise ValueError( + f"You cannot specify both {err_msg_prefix}input_ids and {err_msg_prefix}inputs_embeds at the same time" + ) + elif input_ids is not None: + input_shape = input_ids.size() + input_ids = input_ids.view(-1, input_shape[-1]) + elif inputs_embeds is not None: + input_shape = inputs_embeds.size()[:-1] + else: + err_msg_prefix = "decoder_" if self.is_decoder else "" + raise ValueError(f"You have to specify either {err_msg_prefix}input_ids or {err_msg_prefix}inputs_embeds") + + if inputs_embeds is None: + assert self.embed_tokens is not None, "You have to initialize the model with valid token embeddings" + inputs_embeds = self.embed_tokens(input_ids) + + batch_size, seq_length = input_shape + + # required mask seq length can be calculated via length of past + mask_seq_length = past_key_values[0][0].shape[2] + seq_length if past_key_values is not None else seq_length + + if use_cache is True: + assert self.is_decoder, f"`use_cache` can only be set to `True` if {self} is used as a decoder" + + if attention_mask is None: + attention_mask = torch.ones(batch_size, mask_seq_length, device=inputs_embeds.device) + if self.is_decoder and encoder_attention_mask is None and encoder_hidden_states is not None: + encoder_seq_length = encoder_hidden_states.shape[1] + encoder_attention_mask = torch.ones( + batch_size, encoder_seq_length, device=inputs_embeds.device, dtype=torch.long + ) + + # initialize past_key_values with `None` if past does not exist + if past_key_values is None: + past_key_values = [None] * len(self.block) + + # We can provide a self-attention mask of dimensions [batch_size, from_seq_length, to_seq_length] + # ourselves in which case we just need to make it broadcastable to all heads. + extended_attention_mask = self.get_extended_attention_mask(attention_mask, input_shape) + + # If a 2D or 3D attention mask is provided for the cross-attention + # we need to make broadcastable to [batch_size, num_heads, seq_length, seq_length] + if self.is_decoder and encoder_hidden_states is not None: + encoder_batch_size, encoder_sequence_length, _ = encoder_hidden_states.size() + encoder_hidden_shape = (encoder_batch_size, encoder_sequence_length) + if encoder_attention_mask is None: + encoder_attention_mask = torch.ones(encoder_hidden_shape, device=inputs_embeds.device) + encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask) + else: + encoder_extended_attention_mask = None + + if self.gradient_checkpointing and self.training: + if use_cache: + logger.warning_once( + "`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..." + ) + use_cache = False + + # Prepare head mask if needed + head_mask = self.get_head_mask(head_mask, self.config.num_layers) + cross_attn_head_mask = self.get_head_mask(cross_attn_head_mask, self.config.num_layers) + present_key_value_states = () if use_cache else None + all_hidden_states = () if output_hidden_states else None + all_attentions = () if output_attentions else None + all_cross_attentions = () if (output_attentions and self.is_decoder) else None + position_bias = None + encoder_decoder_position_bias = None + + hidden_states = self.dropout(inputs_embeds) + + for i, (layer_module, past_key_value) in enumerate(zip(self.block, past_key_values)): + layer_head_mask = head_mask[i] + cross_attn_layer_head_mask = cross_attn_head_mask[i] + # Model parallel + if self.model_parallel: + torch.cuda.set_device(hidden_states.device) + # Ensure that attention_mask is always on the same device as hidden_states + if attention_mask is not None: + attention_mask = attention_mask.to(hidden_states.device) + if position_bias is not None: + position_bias = position_bias.to(hidden_states.device) + if encoder_hidden_states is not None: + encoder_hidden_states = encoder_hidden_states.to(hidden_states.device) + if encoder_extended_attention_mask is not None: + encoder_extended_attention_mask = encoder_extended_attention_mask.to(hidden_states.device) + if encoder_decoder_position_bias is not None: + encoder_decoder_position_bias = encoder_decoder_position_bias.to(hidden_states.device) + if layer_head_mask is not None: + layer_head_mask = layer_head_mask.to(hidden_states.device) + if cross_attn_layer_head_mask is not None: + cross_attn_layer_head_mask = cross_attn_layer_head_mask.to(hidden_states.device) + if output_hidden_states: + all_hidden_states = all_hidden_states + (hidden_states,) + + if self.gradient_checkpointing and self.training: + + def create_custom_forward(module): + def custom_forward(*inputs): + return tuple(module(*inputs, use_cache, output_attentions)) + + return custom_forward + + layer_outputs = checkpoint( + create_custom_forward(layer_module), + hidden_states, + extended_attention_mask, + position_bias, + encoder_hidden_states, + encoder_extended_attention_mask, + encoder_decoder_position_bias, + layer_head_mask, + cross_attn_layer_head_mask, + None, # past_key_value is always None with gradient checkpointing + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + else: + layer_outputs = layer_module( + hidden_states, + attention_mask=extended_attention_mask, + position_bias=position_bias, + encoder_hidden_states=encoder_hidden_states, + encoder_attention_mask=encoder_extended_attention_mask, + encoder_decoder_position_bias=encoder_decoder_position_bias, + layer_head_mask=layer_head_mask, + cross_attn_layer_head_mask=cross_attn_layer_head_mask, + past_key_value=past_key_value, + use_cache=use_cache, + output_attentions=output_attentions, + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + + # layer_outputs is a tuple with: + # hidden-states, key-value-states, (self-attention position bias), (self-attention weights), (cross-attention position bias), (cross-attention weights) + if use_cache is False: + layer_outputs = layer_outputs[:1] + (None,) + layer_outputs[1:] + + hidden_states, present_key_value_state = layer_outputs[:2] + + # We share the position biases between the layers - the first layer store them + # layer_outputs = hidden-states, key-value-states (self-attention position bias), (self-attention weights), + # (cross-attention position bias), (cross-attention weights) + position_bias = layer_outputs[2] + if self.is_decoder and encoder_hidden_states is not None: + encoder_decoder_position_bias = layer_outputs[4 if output_attentions else 3] + # append next layer key value states + if use_cache: + present_key_value_states = present_key_value_states + (present_key_value_state,) + + if output_attentions: + all_attentions = all_attentions + (layer_outputs[3],) + if self.is_decoder: + all_cross_attentions = all_cross_attentions + (layer_outputs[5],) + + # Model Parallel: If it's the last layer for that device, put things on the next device + if self.model_parallel: + for k, v in self.device_map.items(): + if i == v[-1] and "cuda:" + str(k) != self.last_device: + hidden_states = hidden_states.to("cuda:" + str(k + 1)) + + hidden_states = self.final_layer_norm(hidden_states) + hidden_states = self.dropout(hidden_states) + + # Add last layer + if output_hidden_states: + all_hidden_states = all_hidden_states + (hidden_states,) + + if not return_dict: + return tuple( + v + for v in [ + hidden_states, + present_key_value_states, + all_hidden_states, + all_attentions, + all_cross_attentions, + ] + if v is not None + ) + return BaseModelOutputWithPastAndCrossAttentions( + last_hidden_state=hidden_states, + past_key_values=present_key_value_states, + hidden_states=all_hidden_states, + attentions=all_attentions, + cross_attentions=all_cross_attentions, + ) + + +T5_START_DOCSTRING = r""" + + The T5 model was proposed in [Exploring the Limits of Transfer Learning with a Unified Text-to-Text + Transformer](https://arxiv.org/abs/1910.10683) by Colin Raffel, Noam Shazeer, Adam Roberts, Katherine Lee, Sharan + Narang, Michael Matena, Yanqi Zhou, Wei Li, Peter J. Liu. It's an encoder decoder transformer pre-trained in a + text-to-text denoising generative setting. + + This model inherits from [`PreTrainedModel`]. Check the superclass documentation for the generic methods the + library implements for all its model (such as downloading or saving, resizing the input embeddings, pruning heads + etc.) + + This model is also a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass. + Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage + and behavior. + + Parameters: + config ([`T5Config`]): Model configuration class with all the parameters of the model. + Initializing with a config file does not load the weights associated with the model, only the + configuration. Check out the [`~PreTrainedModel.from_pretrained`] method to load the model weights. +""" + +T5_INPUTS_DOCSTRING = r""" + Args: + input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`): + Indices of input sequence tokens in the vocabulary. T5 is a model with relative position embeddings so you + should be able to pad the inputs on both the right and the left. + + Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and + [`PreTrainedTokenizer.__call__`] for detail. + + [What are input IDs?](../glossary#input-ids) + + To know more on how to prepare `input_ids` for pretraining take a look a [T5 Training](./t5#training). + attention_mask (`torch.FloatTensor` of shape `(batch_size, sequence_length)`, *optional*): + Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`: + + - 1 for tokens that are **not masked**, + - 0 for tokens that are **masked**. + + [What are attention masks?](../glossary#attention-mask) + decoder_input_ids (`torch.LongTensor` of shape `(batch_size, target_sequence_length)`, *optional*): + Indices of decoder input sequence tokens in the vocabulary. + + Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and + [`PreTrainedTokenizer.__call__`] for details. + + [What are decoder input IDs?](../glossary#decoder-input-ids) + + T5 uses the `pad_token_id` as the starting token for `decoder_input_ids` generation. If `past_key_values` + is used, optionally only the last `decoder_input_ids` have to be input (see `past_key_values`). + + To know more on how to prepare `decoder_input_ids` for pretraining take a look at [T5 + Training](./t5#training). + decoder_attention_mask (`torch.BoolTensor` of shape `(batch_size, target_sequence_length)`, *optional*): + Default behavior: generate a tensor that ignores pad tokens in `decoder_input_ids`. Causal mask will also + be used by default. + head_mask (`torch.FloatTensor` of shape `(num_heads,)` or `(num_layers, num_heads)`, *optional*): + Mask to nullify selected heads of the self-attention modules in the encoder. Mask values selected in `[0, + 1]`: + + - 1 indicates the head is **not masked**, + - 0 indicates the head is **masked**. + + decoder_head_mask (`torch.FloatTensor` of shape `(num_heads,)` or `(num_layers, num_heads)`, *optional*): + Mask to nullify selected heads of the self-attention modules in the decoder. Mask values selected in `[0, + 1]`: + + - 1 indicates the head is **not masked**, + - 0 indicates the head is **masked**. + + cross_attn_head_mask (`torch.Tensor` of shape `(num_heads,)` or `(num_layers, num_heads)`, *optional*): + Mask to nullify selected heads of the cross-attention modules in the decoder. Mask values selected in + `[0, 1]`: + + - 1 indicates the head is **not masked**, + - 0 indicates the head is **masked**. + + encoder_outputs (`tuple(tuple(torch.FloatTensor)`, *optional*): + Tuple consists of (`last_hidden_state`, `optional`: *hidden_states*, `optional`: *attentions*) + `last_hidden_state` of shape `(batch_size, sequence_length, hidden_size)` is a sequence of hidden states at + the output of the last layer of the encoder. Used in the cross-attention of the decoder. + past_key_values (`tuple(tuple(torch.FloatTensor))` of length `config.n_layers` with each tuple having 4 tensors of shape `(batch_size, num_heads, sequence_length - 1, embed_size_per_head)`): + Contains precomputed key and value hidden states of the attention blocks. Can be used to speed up decoding. + + If `past_key_values` are used, the user can optionally input only the last `decoder_input_ids` (those that + don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all + `decoder_input_ids` of shape `(batch_size, sequence_length)`. + inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*): + Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This + is useful if you want more control over how to convert `input_ids` indices into associated vectors than the + model's internal embedding lookup matrix. + decoder_inputs_embeds (`torch.FloatTensor` of shape `(batch_size, target_sequence_length, hidden_size)`, *optional*): + Optionally, instead of passing `decoder_input_ids` you can choose to directly pass an embedded + representation. If `past_key_values` is used, optionally only the last `decoder_inputs_embeds` have to be + input (see `past_key_values`). This is useful if you want more control over how to convert + `decoder_input_ids` indices into associated vectors than the model's internal embedding lookup matrix. + + If `decoder_input_ids` and `decoder_inputs_embeds` are both unset, `decoder_inputs_embeds` takes the value + of `inputs_embeds`. + + use_cache (`bool`, *optional*): + If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see + `past_key_values`). + + output_attentions (`bool`, *optional*): + Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned + tensors for more detail. + output_hidden_states (`bool`, *optional*): + Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for + more detail. + return_dict (`bool`, *optional*): + Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple. +""" + +T5_ENCODER_INPUTS_DOCSTRING = r""" + Args: + input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`): + Indices of input sequence tokens in the vocabulary. T5 is a model with relative position embeddings so you + should be able to pad the inputs on both the right and the left. + + Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and + [`PreTrainedTokenizer.__call__`] for detail. + + To know more on how to prepare `input_ids` for pretraining take a look a [T5 Training](./t5#training). + attention_mask (`torch.FloatTensor` of shape `(batch_size, sequence_length)`, *optional*): + Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`: + + - 1 for tokens that are **not masked**, + - 0 for tokens that are **masked**. + + [What are attention masks?](../glossary#attention-mask) + head_mask (`torch.FloatTensor` of shape `(num_heads,)` or `(num_layers, num_heads)`, *optional*): + Mask to nullify selected heads of the self-attention modules. Mask values selected in `[0, 1]`: + + - 1 indicates the head is **not masked**, + - 0 indicates the head is **masked**. + + inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*): + Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This + is useful if you want more control over how to convert `input_ids` indices into associated vectors than the + model's internal embedding lookup matrix. + output_attentions (`bool`, *optional*): + Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned + tensors for more detail. + output_hidden_states (`bool`, *optional*): + Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for + more detail. + return_dict (`bool`, *optional*): + Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple. +""" + +# Warning message for FutureWarning: head_mask was separated into two input args - head_mask, decoder_head_mask +__HEAD_MASK_WARNING_MSG = """ +The input argument `head_mask` was split into two arguments `head_mask` and `decoder_head_mask`. Currently, +`decoder_head_mask` is set to copy `head_mask`, but this feature is deprecated and will be removed in future versions. +If you do not want to use any `decoder_head_mask` now, please set `decoder_head_mask = torch.ones(num_layers, +num_heads)`. +""" + + +@add_start_docstrings( + "The bare T5 Model transformer outputting raw hidden-states without any specific head on top.", + T5_START_DOCSTRING, +) +class T5Model(T5PreTrainedModel): + _keys_to_ignore_on_load_missing = [ + r"encoder.embed_tokens.weight", + r"decoder.embed_tokens.weight", + ] + _keys_to_ignore_on_load_unexpected = [ + r"decoder.block.0.layer.1.EncDecAttention.relative_attention_bias.weight", + ] + + def __init__(self, config: T5Config): + raise NotImplementedError("might need adjustments for GLM") + super().__init__(config) + self.shared = nn.Embedding(config.vocab_size, config.d_model) + + encoder_config = copy.deepcopy(config) + encoder_config.is_decoder = False + encoder_config.use_cache = False + encoder_config.is_encoder_decoder = False + self.encoder = T5Stack(encoder_config, self.shared) + + decoder_config = copy.deepcopy(config) + decoder_config.is_decoder = True + decoder_config.is_encoder_decoder = False + decoder_config.num_layers = config.num_decoder_layers + self.decoder = T5Stack(decoder_config, self.shared) + + # Initialize weights and apply final processing + self.post_init() + + # Model parallel + self.model_parallel = False + self.device_map = None + + @add_start_docstrings(PARALLELIZE_DOCSTRING) + def parallelize(self, device_map=None): + warnings.warn( + "`T5Model.parallelize` is deprecated and will be removed in v5 of Transformers, you should load your model" + " with `device_map='balanced'` in the call to `from_pretrained`. You can also provide your own" + " `device_map` but it needs to be a dictionary module_name to device, so for instance {'encoder.block.0':" + " 0, 'encoder.block.1': 1, ...}", + FutureWarning, + ) + self.device_map = ( + get_device_map(len(self.encoder.block), range(torch.cuda.device_count())) + if device_map is None + else device_map + ) + assert_device_map(self.device_map, len(self.encoder.block)) + self.encoder.parallelize(self.device_map) + self.decoder.parallelize(self.device_map) + self.model_parallel = True + + @add_start_docstrings(DEPARALLELIZE_DOCSTRING) + def deparallelize(self): + warnings.warn( + "Like `parallelize`, `deparallelize` is deprecated and will be removed in v5 of Transformers.", + FutureWarning, + ) + self.encoder.deparallelize() + self.decoder.deparallelize() + self.encoder = self.encoder.to("cpu") + self.decoder = self.decoder.to("cpu") + self.model_parallel = False + self.device_map = None + torch.cuda.empty_cache() + + def get_input_embeddings(self): + return self.shared + + def set_input_embeddings(self, new_embeddings): + self.shared = new_embeddings + self.encoder.set_input_embeddings(new_embeddings) + self.decoder.set_input_embeddings(new_embeddings) + + def get_encoder(self): + return self.encoder + + def get_decoder(self): + return self.decoder + + def _prune_heads(self, heads_to_prune): + """ + Prunes heads of the model. heads_to_prune: dict of {layer_num: list of heads to prune in this layer} See base + class PreTrainedModel + """ + for layer, heads in heads_to_prune.items(): + self.encoder.layer[layer].attention.prune_heads(heads) + + @add_start_docstrings_to_model_forward(T5_INPUTS_DOCSTRING) + @replace_return_docstrings(output_type=Seq2SeqModelOutput, config_class=_CONFIG_FOR_DOC) + def forward( + self, + input_ids: Optional[torch.LongTensor] = None, + attention_mask: Optional[torch.FloatTensor] = None, + decoder_input_ids: Optional[torch.LongTensor] = None, + decoder_attention_mask: Optional[torch.BoolTensor] = None, + head_mask: Optional[torch.FloatTensor] = None, + decoder_head_mask: Optional[torch.FloatTensor] = None, + cross_attn_head_mask: Optional[torch.Tensor] = None, + encoder_outputs: Optional[Tuple[Tuple[torch.FloatTensor]]] = None, + past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None, + inputs_embeds: Optional[torch.Tensor] = None, + decoder_inputs_embeds: Optional[torch.Tensor] = None, + use_cache: Optional[bool] = None, + output_attentions: Optional[bool] = None, + output_hidden_states: Optional[bool] = None, + return_dict: Optional[bool] = None, + ) -> Union[Tuple[torch.FloatTensor], Seq2SeqModelOutput]: + r""" + Returns: + + Example: + + ```python + >>> from transformers import AutoTokenizer, T5Model + + >>> tokenizer = AutoTokenizer.from_pretrained("t5-small") + >>> model = T5Model.from_pretrained("t5-small") + + >>> input_ids = tokenizer( + ... "Studies have been shown that owning a dog is good for you", return_tensors="pt" + ... ).input_ids # Batch size 1 + >>> decoder_input_ids = tokenizer("Studies show that", return_tensors="pt").input_ids # Batch size 1 + + >>> # preprocess: Prepend decoder_input_ids with start token which is pad token for T5Model. + >>> # This is not needed for torch's T5ForConditionalGeneration as it does this internally using labels arg. + >>> decoder_input_ids = model._shift_right(decoder_input_ids) + + >>> # forward pass + >>> outputs = model(input_ids=input_ids, decoder_input_ids=decoder_input_ids) + >>> last_hidden_states = outputs.last_hidden_state + ```""" + use_cache = use_cache if use_cache is not None else self.config.use_cache + return_dict = return_dict if return_dict is not None else self.config.use_return_dict + + # FutureWarning: head_mask was separated into two input args - head_mask, decoder_head_mask + if head_mask is not None and decoder_head_mask is None: + if self.config.num_layers == self.config.num_decoder_layers: + warnings.warn(__HEAD_MASK_WARNING_MSG, FutureWarning) + decoder_head_mask = head_mask + + # Encode if needed (training, first prediction pass) + if encoder_outputs is None: + encoder_outputs = self.encoder( + input_ids=input_ids, + attention_mask=attention_mask, + inputs_embeds=inputs_embeds, + head_mask=head_mask, + output_attentions=output_attentions, + output_hidden_states=output_hidden_states, + return_dict=return_dict, + ) + elif return_dict and not isinstance(encoder_outputs, BaseModelOutput): + encoder_outputs = BaseModelOutput( + last_hidden_state=encoder_outputs[0], + hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None, + attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None, + ) + + hidden_states = encoder_outputs[0] + + # Set device for model parallelism + if self.model_parallel: + torch.cuda.set_device(self.decoder.first_device) + hidden_states = hidden_states.to(self.decoder.first_device) + if decoder_input_ids is not None: + decoder_input_ids = decoder_input_ids.to(self.decoder.first_device) + if attention_mask is not None: + attention_mask = attention_mask.to(self.decoder.first_device) + if decoder_attention_mask is not None: + decoder_attention_mask = decoder_attention_mask.to(self.decoder.first_device) + + # Decode + decoder_outputs = self.decoder( + input_ids=decoder_input_ids, + attention_mask=decoder_attention_mask, + inputs_embeds=decoder_inputs_embeds, + past_key_values=past_key_values, + encoder_hidden_states=hidden_states, + encoder_attention_mask=attention_mask, + head_mask=decoder_head_mask, + cross_attn_head_mask=cross_attn_head_mask, + use_cache=use_cache, + output_attentions=output_attentions, + output_hidden_states=output_hidden_states, + return_dict=return_dict, + ) + + if not return_dict: + return decoder_outputs + encoder_outputs + + return Seq2SeqModelOutput( + last_hidden_state=decoder_outputs.last_hidden_state, + past_key_values=decoder_outputs.past_key_values, + decoder_hidden_states=decoder_outputs.hidden_states, + decoder_attentions=decoder_outputs.attentions, + cross_attentions=decoder_outputs.cross_attentions, + encoder_last_hidden_state=encoder_outputs.last_hidden_state, + encoder_hidden_states=encoder_outputs.hidden_states, + encoder_attentions=encoder_outputs.attentions, + ) + + +@add_start_docstrings("""T5 Model with a `language modeling` head on top.""", T5_START_DOCSTRING) +class T5ForConditionalGeneration(T5PreTrainedModel): + _keys_to_ignore_on_load_missing = [ + r"encoder.embed_tokens.weight", + r"decoder.embed_tokens.weight", + r"lm_head.weight", + ] + _keys_to_ignore_on_load_unexpected = [ + r"decoder.block.0.layer.1.EncDecAttention.relative_attention_bias.weight", + ] + + def __init__(self, config: T5Config): + raise NotImplementedError("might need adjustments for GLM") + super().__init__(config) + self.model_dim = config.d_model + + self.shared = nn.Embedding(config.vocab_size, config.d_model) + + encoder_config = copy.deepcopy(config) + encoder_config.is_decoder = False + encoder_config.use_cache = False + encoder_config.is_encoder_decoder = False + self.encoder = T5Stack(encoder_config, self.shared) + + decoder_config = copy.deepcopy(config) + decoder_config.is_decoder = True + decoder_config.is_encoder_decoder = False + decoder_config.num_layers = config.num_decoder_layers + self.decoder = T5Stack(decoder_config, self.shared) + + self.lm_head = nn.Linear(config.d_model, config.vocab_size, bias=False) + + # Initialize weights and apply final processing + self.post_init() + + # Model parallel + self.model_parallel = False + self.device_map = None + + @add_start_docstrings(PARALLELIZE_DOCSTRING) + def parallelize(self, device_map=None): + warnings.warn( + "`T5ForConditionalGeneration.parallelize` is deprecated and will be removed in v5 of Transformers, you" + " should load your model with `device_map='balanced'` in the call to `from_pretrained`. You can also" + " provide your own `device_map` but it needs to be a dictionary module_name to device, so for instance" + " {'encoder.block.0': 0, 'encoder.block.1': 1, ...}", + FutureWarning, + ) + self.device_map = ( + get_device_map(len(self.encoder.block), range(torch.cuda.device_count())) + if device_map is None + else device_map + ) + assert_device_map(self.device_map, len(self.encoder.block)) + self.encoder.parallelize(self.device_map) + self.decoder.parallelize(self.device_map) + self.lm_head = self.lm_head.to(self.decoder.first_device) + self.model_parallel = True + + @add_start_docstrings(DEPARALLELIZE_DOCSTRING) + def deparallelize(self): + warnings.warn( + "Like `parallelize`, `deparallelize` is deprecated and will be removed in v5 of Transformers.", + FutureWarning, + ) + self.encoder.deparallelize() + self.decoder.deparallelize() + self.encoder = self.encoder.to("cpu") + self.decoder = self.decoder.to("cpu") + self.lm_head = self.lm_head.to("cpu") + self.model_parallel = False + self.device_map = None + torch.cuda.empty_cache() + + def get_input_embeddings(self): + return self.shared + + def set_input_embeddings(self, new_embeddings): + self.shared = new_embeddings + self.encoder.set_input_embeddings(new_embeddings) + self.decoder.set_input_embeddings(new_embeddings) + + def set_output_embeddings(self, new_embeddings): + self.lm_head = new_embeddings + + def get_output_embeddings(self): + return self.lm_head + + def get_encoder(self): + return self.encoder + + def get_decoder(self): + return self.decoder + + @add_start_docstrings_to_model_forward(T5_INPUTS_DOCSTRING) + @replace_return_docstrings(output_type=Seq2SeqLMOutput, config_class=_CONFIG_FOR_DOC) + def forward( + self, + input_ids: Optional[torch.LongTensor] = None, + attention_mask: Optional[torch.FloatTensor] = None, + decoder_input_ids: Optional[torch.LongTensor] = None, + decoder_attention_mask: Optional[torch.BoolTensor] = None, + head_mask: Optional[torch.FloatTensor] = None, + decoder_head_mask: Optional[torch.FloatTensor] = None, + cross_attn_head_mask: Optional[torch.Tensor] = None, + encoder_outputs: Optional[Tuple[Tuple[torch.Tensor]]] = None, + past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None, + inputs_embeds: Optional[torch.FloatTensor] = None, + decoder_inputs_embeds: Optional[torch.FloatTensor] = None, + labels: Optional[torch.LongTensor] = None, + use_cache: Optional[bool] = None, + output_attentions: Optional[bool] = None, + output_hidden_states: Optional[bool] = None, + return_dict: Optional[bool] = None, + relative_position = None, # only for Encoder; CrossAttention does not use PE and SelfAttention in decoder is operating on a sequence + sparsity_mask = None, # only for Encoder; CrossAttention does not use PE and SelfAttention in decoder is operating on a sequence; However, could be implemented for CrossAttention aswell, to e.g. mask out tokens from relations + is_concept: Optional[torch.BoolTensor] = None, # Either None, or tensor of shape (batch_size, max_sequence_length). If not None, then the encoder only gets embeddings of concepts but not of relations. + concept_indices: Optional[list[dict[str,tuple[int,int]]]] = None, # Either None, or list (len=batchsize)of dicts. If not None, then the encoder-embeddings of concepts are aggregated across multiple occurances of a single concept. This can be applied to make the LM baselines work as a graph-encdoer. Then the decoder gets the encoded graph as input, instead of the series of verbalized triplets. + use_additional_bucket: Optional[torch.BoolTensor] = None, + ) -> Union[Tuple[torch.FloatTensor], Seq2SeqLMOutput]: + r""" + labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*): + Labels for computing the sequence classification/regression loss. Indices should be in `[-100, 0, ..., + config.vocab_size - 1]`. All labels set to `-100` are ignored (masked), the loss is only computed for + labels in `[0, ..., config.vocab_size]` + + Returns: + + Examples: + + ```python + >>> from transformers import AutoTokenizer, T5ForConditionalGeneration + + >>> tokenizer = AutoTokenizer.from_pretrained("t5-small") + >>> model = T5ForConditionalGeneration.from_pretrained("t5-small") + + >>> # training + >>> input_ids = tokenizer("The walks in park", return_tensors="pt").input_ids + >>> labels = tokenizer(" cute dog the ", return_tensors="pt").input_ids + >>> outputs = model(input_ids=input_ids, labels=labels) + >>> loss = outputs.loss + >>> logits = outputs.logits + + >>> # inference + >>> input_ids = tokenizer( + ... "summarize: studies have shown that owning a dog is good for you", return_tensors="pt" + ... ).input_ids # Batch size 1 + >>> outputs = model.generate(input_ids) + >>> print(tokenizer.decode(outputs[0], skip_special_tokens=True)) + >>> # studies have shown that owning a dog is good for you. + ```""" + use_cache = use_cache if use_cache is not None else self.config.use_cache + return_dict = return_dict if return_dict is not None else self.config.use_return_dict + + # FutureWarning: head_mask was separated into two input args - head_mask, decoder_head_mask + if head_mask is not None and decoder_head_mask is None: + if self.config.num_layers == self.config.num_decoder_layers: + warnings.warn(__HEAD_MASK_WARNING_MSG, FutureWarning) + decoder_head_mask = head_mask + + # Encode if needed (training, first prediction pass) + if encoder_outputs is None: + # Convert encoder inputs in embeddings if needed + encoder_outputs = self.encoder( + input_ids=input_ids, + attention_mask=attention_mask, + inputs_embeds=inputs_embeds, + head_mask=head_mask, + output_attentions=output_attentions, + output_hidden_states=output_hidden_states, + return_dict=return_dict, + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + elif return_dict and not isinstance(encoder_outputs, BaseModelOutput): + encoder_outputs = BaseModelOutput( + last_hidden_state=encoder_outputs[0], + hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None, + attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None, + ) + + hidden_states = encoder_outputs[0] + + if self.model_parallel: + torch.cuda.set_device(self.decoder.first_device) + + if labels is not None and decoder_input_ids is None and decoder_inputs_embeds is None: + # get decoder inputs from shifting lm labels to the right + decoder_input_ids = self._shift_right(labels) + + # Set device for model parallelism + if self.model_parallel: + torch.cuda.set_device(self.decoder.first_device) + hidden_states = hidden_states.to(self.decoder.first_device) + if decoder_input_ids is not None: + decoder_input_ids = decoder_input_ids.to(self.decoder.first_device) + if attention_mask is not None: + attention_mask = attention_mask.to(self.decoder.first_device) + if decoder_attention_mask is not None: + decoder_attention_mask = decoder_attention_mask.to(self.decoder.first_device) + + if is_concept is not None: # decoder only attends to concepts + attention_mask = attention_mask * is_concept + + if concept_indices is not None: # aggregate concept embeddings of encoder + # print(f'{hidden_states.shape = }') + # torch.save(hidden_states, 'hidden_states.pt') + # torch.save(attention_mask, 'attention_mask.pt') + # torch.save(concept_indices, 'concept_indices.pt') + # torch.save(is_concept, 'is_concept.pt') + # assert False + for b, tmp_batch_concept_indices in enumerate(concept_indices): # iterate over batch + for tmp_concept_indices in tmp_batch_concept_indices.values(): # iterate over concepts + tmp_indices = torch.tensor([[i for i in range(*one_concept_occurance)] for one_concept_occurance in tmp_concept_indices], device=hidden_states.device).T # shape (token-length-of-concept, num-occurances-of-concept) + + for tmp_tok_indices in tmp_indices: # iterate over tokens within each concept + hidden_states[b,tmp_tok_indices] = torch.index_select(hidden_states[b], 0, tmp_tok_indices).mean(dim=0, keepdim=True) # save mean over all occurances + + attention_mask[b, tmp_indices[:,1:]] = False # only attend to first occurace + + + # Decode + decoder_outputs = self.decoder( + input_ids=decoder_input_ids, + attention_mask=decoder_attention_mask, + inputs_embeds=decoder_inputs_embeds, + past_key_values=past_key_values, + encoder_hidden_states=hidden_states, + encoder_attention_mask=attention_mask, + head_mask=decoder_head_mask, + cross_attn_head_mask=cross_attn_head_mask, + use_cache=use_cache, + output_attentions=output_attentions, + output_hidden_states=output_hidden_states, + return_dict=return_dict, + ) + + sequence_output = decoder_outputs[0] + + # Set device for model parallelism + if self.model_parallel: + torch.cuda.set_device(self.encoder.first_device) + self.lm_head = self.lm_head.to(self.encoder.first_device) + sequence_output = sequence_output.to(self.lm_head.weight.device) + + if self.config.tie_word_embeddings: + # Rescale output before projecting on vocab + # See https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/transformer/transformer.py#L586 + sequence_output = sequence_output * (self.model_dim**-0.5) + + lm_logits = self.lm_head(sequence_output) + + loss = None + if labels is not None: + loss_fct = CrossEntropyLoss(ignore_index=-100) + loss = loss_fct(lm_logits.view(-1, lm_logits.size(-1)), labels.view(-1)) + # TODO(thom): Add z_loss https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/layers.py#L666 + + if not return_dict: + output = (lm_logits,) + decoder_outputs[1:] + encoder_outputs + return ((loss,) + output) if loss is not None else output + + return Seq2SeqLMOutput( + loss=loss, + logits=lm_logits, + past_key_values=decoder_outputs.past_key_values, + decoder_hidden_states=decoder_outputs.hidden_states, + decoder_attentions=decoder_outputs.attentions, + cross_attentions=decoder_outputs.cross_attentions, + encoder_last_hidden_state=encoder_outputs.last_hidden_state, + encoder_hidden_states=encoder_outputs.hidden_states, + encoder_attentions=encoder_outputs.attentions, + ) + + def prepare_inputs_for_generation( + self, + input_ids, + past_key_values=None, + attention_mask=None, + head_mask=None, + decoder_head_mask=None, + cross_attn_head_mask=None, + use_cache=None, + encoder_outputs=None, + **kwargs, + ): + # cut decoder_input_ids if past is used + if past_key_values is not None: + input_ids = input_ids[:, -1:] + + return { + "decoder_input_ids": input_ids, + "past_key_values": past_key_values, + "encoder_outputs": encoder_outputs, + "attention_mask": attention_mask, + "head_mask": head_mask, + "decoder_head_mask": decoder_head_mask, + "cross_attn_head_mask": cross_attn_head_mask, + "use_cache": use_cache, + } + + def prepare_decoder_input_ids_from_labels(self, labels: torch.Tensor): + return self._shift_right(labels) + + def _reorder_cache(self, past_key_values, beam_idx): + # if decoder past is not included in output + # speedy decoding is disabled and no need to reorder + if past_key_values is None: + logger.warning("You might want to consider setting `use_cache=True` to speed up decoding") + return past_key_values + + reordered_decoder_past = () + for layer_past_states in past_key_values: + # get the correct batch idx from layer past batch dim + # batch dim of `past` is at 2nd position + reordered_layer_past_states = () + for layer_past_state in layer_past_states: + # need to set correct `past` for each of the four key / value states + reordered_layer_past_states = reordered_layer_past_states + ( + layer_past_state.index_select(0, beam_idx.to(layer_past_state.device)), + ) + + assert reordered_layer_past_states[0].shape == layer_past_states[0].shape + assert len(reordered_layer_past_states) == len(layer_past_states) + + reordered_decoder_past = reordered_decoder_past + (reordered_layer_past_states,) + return reordered_decoder_past + +@add_start_docstrings( + "The bare T5 Model transformer outputting encoder's raw hidden-states without any specific head on top.", + T5_START_DOCSTRING, +) +class T5EncoderModel(T5PreTrainedModel): + _keys_to_ignore_on_load_missing = [r"encoder.embed_tokens.weight"] + + def __init__(self, config: T5Config): + super().__init__(config) + self.shared = nn.Embedding(config.vocab_size, config.d_model) + + encoder_config = copy.deepcopy(config) + encoder_config.use_cache = False + encoder_config.is_encoder_decoder = False + self.encoder = T5Stack(encoder_config, self.shared) + + # Initialize weights and apply final processing + self.post_init() + + # Model parallel + self.model_parallel = False + self.device_map = None + + @add_start_docstrings(PARALLELIZE_DOCSTRING) + def parallelize(self, device_map=None): + warnings.warn( + "`T5EncoderModel.parallelize` is deprecated and will be removed in v5 of Transformers, you should load" + " your model with `device_map='balanced'` in the call to `from_pretrained`. You can also provide your own" + " `device_map` but it needs to be a dictionary module_name to device, so for instance {'block.0': 0," + " 'block.1': 1, ...}", + FutureWarning, + ) + self.device_map = ( + get_device_map(len(self.encoder.block), range(torch.cuda.device_count())) + if device_map is None + else device_map + ) + assert_device_map(self.device_map, len(self.encoder.block)) + self.encoder.parallelize(self.device_map) + self.model_parallel = True + + @add_start_docstrings(DEPARALLELIZE_DOCSTRING) + def deparallelize(self): + warnings.warn( + "Like `parallelize`, `deparallelize` is deprecated and will be removed in v5 of Transformers.", + FutureWarning, + ) + self.encoder.deparallelize() + self.encoder = self.encoder.to("cpu") + self.model_parallel = False + self.device_map = None + torch.cuda.empty_cache() + + def get_input_embeddings(self): + return self.shared + + def set_input_embeddings(self, new_embeddings): + self.shared = new_embeddings + self.encoder.set_input_embeddings(new_embeddings) + + def get_encoder(self): + return self.encoder + + def _prune_heads(self, heads_to_prune): + """ + Prunes heads of the model. heads_to_prune: dict of {layer_num: list of heads to prune in this layer} See base + class PreTrainedModel + """ + for layer, heads in heads_to_prune.items(): + self.encoder.block[layer].layer[0].SelfAttention.prune_heads(heads) + + @add_start_docstrings_to_model_forward(T5_ENCODER_INPUTS_DOCSTRING) + @replace_return_docstrings(output_type=BaseModelOutput, config_class=_CONFIG_FOR_DOC) + def forward( + self, + input_ids: Optional[torch.LongTensor] = None, + attention_mask: Optional[torch.FloatTensor] = None, + head_mask: Optional[torch.FloatTensor] = None, + inputs_embeds: Optional[torch.FloatTensor] = None, + output_attentions: Optional[bool] = None, + output_hidden_states: Optional[bool] = None, + return_dict: Optional[bool] = None, + relative_position: Optional[torch.LongTensor] = None, + sparsity_mask: Optional[torch.BoolTensor] = None, + use_additional_bucket: Optional[torch.BoolTensor] = None, + ) -> Union[Tuple[torch.FloatTensor], BaseModelOutput]: + r""" + Returns: + + Example: + + ```python + >>> from transformers import AutoTokenizer, T5EncoderModel + + >>> tokenizer = AutoTokenizer.from_pretrained("t5-small") + >>> model = T5EncoderModel.from_pretrained("t5-small") + >>> input_ids = tokenizer( + ... "Studies have been shown that owning a dog is good for you", return_tensors="pt" + ... ).input_ids # Batch size 1 + >>> outputs = model(input_ids=input_ids) + >>> last_hidden_states = outputs.last_hidden_state + ```""" + return_dict = return_dict if return_dict is not None else self.config.use_return_dict + + encoder_outputs = self.encoder( + input_ids=input_ids, + attention_mask=attention_mask, + inputs_embeds=inputs_embeds, + head_mask=head_mask, + output_attentions=output_attentions, + output_hidden_states=output_hidden_states, + return_dict=return_dict, + relative_position=relative_position, + sparsity_mask=sparsity_mask, + use_additional_bucket=use_additional_bucket, + ) + + return encoder_outputs + + def init_relative_position_bias(self, modelsize:str, init_decoder:bool=False, init_additional_buckets_from:list[int]=None): + if init_decoder: + self.decoder.block[0].layer[0].SelfAttention.init_relative_position_bias(modelsize=modelsize, is_decoder=init_decoder, init_additional_buckets_from=init_additional_buckets_from) + else: + self.encoder.block[0].layer[0].SelfAttention.init_relative_position_bias(modelsize=modelsize, is_decoder=init_decoder, init_additional_buckets_from=init_additional_buckets_from) + + +class GraphT5Classifier(PreTrainedModel): + config_class = T5Config + + def __init__( + self, + config: T5Config, + ): + super().__init__(config=config) + self.config = config + self.tokenizer = T5Tokenizer.from_pretrained(self.config.modelsize, model_max_length=self.config.model_max_length) + + self.t5model = T5EncoderModel.from_pretrained(self.config.modelsize, config=config, ignore_mismatched_sizes=True) # when intialiting the model with .from_pretrained, the weights are loaded from the pretrained model, so the t5 parameters are not actually used in that case. Loading them here is unnecessary overhead. + self.hidden_size = self.t5model.config.d_model + self.classification_head = nn.Linear(self.hidden_size, self.config.num_classes, bias=True) + self.softmax = nn.Softmax(dim=-1) + + @staticmethod + def get_config(num_classes:int, modelsize:str="t5-base", num_additional_buckets:int=0, model_max_length:int=512) -> T5Config: + config = T5Config.from_pretrained(modelsize) + config.num_classes = int(num_classes) + config.modelsize = str(modelsize) + config.relative_attention_num_additional_buckets = int(num_additional_buckets) + config.model_max_length = int(model_max_length) + return config + + def forward( + self, + input_ids: torch.Tensor, + relative_position: torch.Tensor, + sparsity_mask: torch.Tensor, + use_additional_bucket: torch.Tensor, + ) -> torch.Tensor: + logging.debug('t5 encoder model') + output = self.t5model(input_ids=input_ids, relative_position=relative_position, sparsity_mask=sparsity_mask, use_additional_bucket=use_additional_bucket) # (batch_size, seq_len, hidden_size) + logging.debug('classification head') + logits = self.classification_head(output[0]) # (batch_size, seq_len, num_classes) + + return logits + + def get_probabilities(self, logits: torch.Tensor) -> torch.Tensor: + return self.softmax(logits) # (batch_size, seq_len, num_classes) + + def get_label(self, logits: torch.Tensor) -> torch.Tensor: + return torch.argmax(logits, dim=-1) + + +class DualGraphT5Classifier(PreTrainedModel): + """ + Same as GraphT5Classifier, but with two classification heads + """ + config_class = T5Config + + def __init__( + self, + config: T5Config, + ): + super().__init__(config=config) + self.config = config + self.tokenizer = T5Tokenizer.from_pretrained(self.config.modelsize, model_max_length=self.config.model_max_length) + + self.t5model = T5EncoderModel.from_pretrained(self.config.modelsize, config=config, ignore_mismatched_sizes=True) + self.hidden_size = self.t5model.config.d_model + self.classification_head1 = nn.Linear(self.hidden_size, self.config.num_classes1, bias=True) + self.classification_head2 = nn.Linear(self.hidden_size, self.config.num_classes2, bias=True) + self.softmax = nn.Softmax(dim=-1) + + @staticmethod + def get_config(num_classes1:int, num_classes2:int, modelsize:str="t5-base", num_additional_buckets:int=0, model_max_length:int=512) -> T5Config: + config = T5Config.from_pretrained(modelsize) + config.num_classes1 = int(num_classes1) + config.num_classes2 = int(num_classes2) + config.modelsize = str(modelsize) + config.relative_attention_num_additional_buckets = int(num_additional_buckets) + config.model_max_length = int(model_max_length) + return config + + def forward( + self, + input_ids: torch.Tensor, + relative_position: torch.Tensor, + sparsity_mask: torch.Tensor, + use_additional_bucket: torch.Tensor, + ) -> torch.Tensor: + logging.debug('t5 encoder model') + output = self.t5model(input_ids=input_ids, relative_position=relative_position, sparsity_mask=sparsity_mask, use_additional_bucket=use_additional_bucket) # (batch_size, seq_len, hidden_size) + logging.debug('classification head 1') + logits1 = self.classification_head1(output[0]) # (batch_size, seq_len, num_classes1) + logging.debug('classification head 2') + logits2 = self.classification_head2(output[0]) # (batch_size, seq_len, num_classes2) + + return logits1, logits2 + + def get_probabilities(self, logits: torch.Tensor) -> torch.Tensor: + return self.softmax(logits) # (batch_size, seq_len, num_classes) + + def get_label(self, logits: torch.Tensor) -> torch.Tensor: + return torch.argmax(logits, dim=-1) \ No newline at end of file