1601 lines
70 KiB
Python
1601 lines
70 KiB
Python
# coding=utf-8
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# Copyright 2023 The OpenAI Team Authors and HuggingFace Inc. team.
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# Copyright (c) 2018, NVIDIA CORPORATION. All rights reserved.
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# Copyright 2023 Cerebras Systems.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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""" PyTorch JAIS model."""
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import math
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import os
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import warnings
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from typing import Optional, Tuple, Union
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import torch
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from torch import Tensor, nn
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from torch.cuda.amp import autocast
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from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
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from transformers.activations import ACT2FN
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from transformers.modeling_outputs import (
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BaseModelOutputWithPastAndCrossAttentions,
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CausalLMOutputWithCrossAttentions,
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QuestionAnsweringModelOutput,
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SequenceClassifierOutputWithPast,
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TokenClassifierOutput,
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)
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from transformers.modeling_utils import PreTrainedModel
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from transformers.pytorch_utils import Conv1D, find_pruneable_heads_and_indices, prune_conv1d_layer
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from transformers.utils import (
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add_code_sample_docstrings,
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add_start_docstrings,
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add_start_docstrings_to_model_forward,
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logging,
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)
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from transformers.utils.model_parallel_utils import assert_device_map, get_device_map
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from .configuration_jais import JAISConfig
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logger = logging.get_logger(__name__)
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_CHECKPOINT_FOR_DOC = "inceptionai/jais-family-590m"
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_CONFIG_FOR_DOC = "JAISConfig"
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class SwiGLUActivation(nn.Module):
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def forward(self, x1: Tensor, x2: Tensor) -> Tensor:
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return x1 * nn.functional.silu(x2)
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class AlibiPositionEmbeddingLayer(nn.Module):
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def __init__(self, num_heads, alibi_scaling=None):
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super(AlibiPositionEmbeddingLayer, self).__init__()
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self.num_heads = num_heads
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self.alibi_scaling = alibi_scaling
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slopes = torch.tensor(AlibiPositionEmbeddingLayer._get_alibi_slopes(num_heads)).unsqueeze(-1)
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self.slopes = nn.parameter.Parameter(slopes, requires_grad=False)
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def forward(
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self,
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seq_length,
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key_length,
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cached_qk_len,
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):
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context_position = torch.arange(
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cached_qk_len, cached_qk_len + seq_length, device=self.slopes.device
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)[:, None]
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memory_position = torch.arange(
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key_length + cached_qk_len, device=self.slopes.device
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)[None, :]
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relative_position = memory_position - context_position
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relative_position = torch.abs(relative_position).unsqueeze(0).expand(self.num_heads, -1, -1)
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if self.alibi_scaling is None:
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scale = 1.0
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elif self.alibi_scaling.get("factor") is not None:
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scale = self.alibi_scaling["factor"]
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elif relative_position.shape[-1] > self.alibi_scaling["train_seq_len"]:
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scale = relative_position.shape[-1] / self.alibi_scaling["train_seq_len"]
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else:
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scale = 1.0
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alibi = (self.slopes / -scale).unsqueeze(1) * relative_position
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return alibi
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@staticmethod
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def _get_alibi_slopes(n):
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def get_slopes_power_of_2(n):
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start = 2 ** (-(2 ** -(math.log2(n) - 3)))
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ratio = start
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return [start * ratio**i for i in range(n)]
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if math.log2(n).is_integer():
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return get_slopes_power_of_2(
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n
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) # In the paper, we only train models that have 2^a heads for some a. This function has
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else: # some good properties that only occur when the input is a power of 2. To maintain that even
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closest_power_of_2 = 2 ** math.floor(
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math.log2(n)
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) # when the number of heads is not a power of 2, we use this workaround.
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return (
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get_slopes_power_of_2(closest_power_of_2)
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+ AlibiPositionEmbeddingLayer._get_alibi_slopes(2 * closest_power_of_2)[0::2][: n - closest_power_of_2]
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)
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def load_tf_weights_in_jais(model, config, jais_checkpoint_path):
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"""Load tf checkpoints in a pytorch model"""
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try:
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import re
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import tensorflow as tf
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except ImportError:
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logger.error(
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"Loading a TensorFlow model in PyTorch, requires TensorFlow to be installed. Please see "
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"https://www.tensorflow.org/install/ for installation instructions."
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)
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raise
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tf_path = os.path.abspath(jais_checkpoint_path)
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logger.info(f"Converting TensorFlow checkpoint from {tf_path}")
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# Load weights from TF model
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init_vars = tf.train.list_variables(tf_path)
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names = []
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arrays = []
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for name, shape in init_vars:
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logger.info(f"Loading TF weight {name} with shape {shape}")
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array = tf.train.load_variable(tf_path, name)
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names.append(name)
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arrays.append(array.squeeze())
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for name, array in zip(names, arrays):
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name = name[6:] # skip "model/"
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name = name.split("/")
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pointer = model
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for m_name in name:
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if re.fullmatch(r"[A-Za-z]+\d+", m_name):
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scope_names = re.split(r"(\d+)", m_name)
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else:
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scope_names = [m_name]
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if scope_names[0] == "w" or scope_names[0] == "g":
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pointer = getattr(pointer, "weight")
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elif scope_names[0] == "b":
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pointer = getattr(pointer, "bias")
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elif scope_names[0] == "wpe" or scope_names[0] == "wte":
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pointer = getattr(pointer, scope_names[0])
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pointer = getattr(pointer, "weight")
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else:
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pointer = getattr(pointer, scope_names[0])
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if len(scope_names) >= 2:
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num = int(scope_names[1])
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pointer = pointer[num]
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try:
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assert (
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pointer.shape == array.shape
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), f"Pointer shape {pointer.shape} and array shape {array.shape} mismatched"
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except AssertionError as e:
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e.args += (pointer.shape, array.shape)
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raise
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logger.info(f"Initialize PyTorch weight {name}")
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pointer.data = torch.from_numpy(array)
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return model
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class JAISAttention(nn.Module):
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def __init__(self, config, is_cross_attention=False, layer_idx=None):
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super().__init__()
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max_positions = config.max_position_embeddings
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self.register_buffer(
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"bias",
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torch.tril(torch.ones((max_positions, max_positions), dtype=torch.bool)).view(
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1, 1, max_positions, max_positions
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),
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persistent=False,
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)
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self.register_buffer("masked_bias", torch.tensor(-1e4), persistent=False)
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self.embed_dim = config.hidden_size
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self.num_heads = config.num_attention_heads
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self.head_dim = self.embed_dim // self.num_heads
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self.split_size = self.embed_dim
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if self.head_dim * self.num_heads != self.embed_dim:
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raise ValueError(
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f"`embed_dim` must be divisible by num_heads (got `embed_dim`: {self.embed_dim} and `num_heads`:"
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f" {self.num_heads})."
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)
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self.scale_attn_weights = config.scale_attn_weights
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self.is_cross_attention = is_cross_attention
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# Layer-wise attention scaling, reordering, and upcasting
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self.scale_attn_by_inverse_layer_idx = config.scale_attn_by_inverse_layer_idx
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self.layer_idx = layer_idx
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self.reorder_and_upcast_attn = config.reorder_and_upcast_attn
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if self.is_cross_attention:
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self.c_attn = Conv1D(2 * self.embed_dim, self.embed_dim)
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self.q_attn = Conv1D(self.embed_dim, self.embed_dim)
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else:
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self.c_attn = Conv1D(3 * self.embed_dim, self.embed_dim)
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self.c_proj = Conv1D(self.embed_dim, self.embed_dim)
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self.attn_dropout = nn.Dropout(config.attn_pdrop)
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self.resid_dropout = nn.Dropout(config.resid_pdrop)
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self.pruned_heads = set()
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self.attn_scale_power = 1.0 if config.mup_scale_qk_dot_by_d else 0.5
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def prune_heads(self, heads):
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if len(heads) == 0:
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return
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heads, index = find_pruneable_heads_and_indices(heads, self.num_heads, self.head_dim, self.pruned_heads)
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index_attn = torch.cat([index, index + self.split_size, index + (2 * self.split_size)])
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# Prune conv1d layers
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self.c_attn = prune_conv1d_layer(self.c_attn, index_attn, dim=1)
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self.c_proj = prune_conv1d_layer(self.c_proj, index, dim=0)
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# Update hyper params
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self.split_size = (self.split_size // self.num_heads) * (self.num_heads - len(heads))
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self.num_heads = self.num_heads - len(heads)
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self.pruned_heads = self.pruned_heads.union(heads)
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def _attn(self, query, key, value, attention_mask=None, head_mask=None, position_bias=None):
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attn_weights = torch.matmul(query, key.transpose(-1, -2))
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if self.scale_attn_weights:
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attn_weights = attn_weights / torch.full(
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[], value.size(-1) ** self.attn_scale_power, dtype=attn_weights.dtype, device=attn_weights.device
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)
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# Layer-wise attention scaling
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if self.scale_attn_by_inverse_layer_idx:
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attn_weights = attn_weights / float(self.layer_idx + 1)
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if not self.is_cross_attention:
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# if only "normal" attention layer implements causal mask
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query_length, key_length = query.size(-2), key.size(-2)
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causal_mask = self.bias[:, :, key_length - query_length : key_length, :key_length]
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mask_value = torch.finfo(attn_weights.dtype).min
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# Need to be a tensor, otherwise we get error: `RuntimeError: expected scalar type float but found double`.
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# Need to be on the same device, otherwise `RuntimeError: ..., x and y to be on the same device`
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mask_value = torch.full([], mask_value, dtype=attn_weights.dtype).to(attn_weights.device)
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attn_weights = torch.where(causal_mask, attn_weights.to(attn_weights.dtype), mask_value)
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if attention_mask is not None:
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# Apply the attention mask
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attn_weights = attn_weights + attention_mask
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if position_bias is not None:
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attn_weights += position_bias.type_as(attn_weights).unsqueeze(0)
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attn_weights = nn.functional.softmax(attn_weights, dim=-1)
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# Downcast (if necessary) back to V's dtype (if in mixed-precision) -- No-Op otherwise
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attn_weights = attn_weights.type(value.dtype)
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attn_weights = self.attn_dropout(attn_weights)
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# Mask heads if we want to
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if head_mask is not None:
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attn_weights = attn_weights * head_mask
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attn_output = torch.matmul(attn_weights, value)
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return attn_output, attn_weights
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def _upcast_and_reordered_attn(self, query, key, value, attention_mask=None, head_mask=None, position_bias=None):
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# Use `torch.baddbmm` (a bit more efficient w/ alpha param for scaling -- from Megatron-LM)
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bsz, num_heads, q_seq_len, dk = query.size()
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_, _, k_seq_len, _ = key.size()
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# Preallocate attn_weights for `baddbmm`
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attn_weights = torch.empty(bsz * num_heads, q_seq_len, k_seq_len, dtype=torch.float32, device=query.device)
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# Compute Scale Factor
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scale_factor = 1.0
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if self.scale_attn_weights:
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scale_factor /= float(value.size(-1)) ** self.attn_scale_power
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if self.scale_attn_by_inverse_layer_idx:
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scale_factor /= float(self.layer_idx + 1)
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# Upcast (turn off autocast) and reorder (Scale K by 1 / root(dk))
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with autocast(enabled=False):
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q, k = query.reshape(-1, q_seq_len, dk), key.transpose(-1, -2).reshape(-1, dk, k_seq_len)
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attn_weights = torch.baddbmm(attn_weights, q.float(), k.float(), beta=0, alpha=scale_factor)
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attn_weights = attn_weights.reshape(bsz, num_heads, q_seq_len, k_seq_len)
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if not self.is_cross_attention:
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# if only "normal" attention layer implements causal mask
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query_length, key_length = query.size(-2), key.size(-2)
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causal_mask = self.bias[:, :, key_length - query_length : key_length, :key_length]
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mask_value = torch.finfo(attn_weights.dtype).min
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# Need to be a tensor, otherwise we get error: `RuntimeError: expected scalar type float but found double`.
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# Need to be on the same device, otherwise `RuntimeError: ..., x and y to be on the same device`
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mask_value = torch.tensor(mask_value, dtype=attn_weights.dtype).to(attn_weights.device)
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attn_weights = torch.where(causal_mask, attn_weights, mask_value)
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if attention_mask is not None:
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# Apply the attention mask
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attn_weights = attn_weights + attention_mask
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if position_bias is not None:
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attn_weights += position_bias.type_as(attn_weights).unsqueeze(0)
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attn_weights = nn.functional.softmax(attn_weights, dim=-1)
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# Downcast (if necessary) back to V's dtype (if in mixed-precision) -- No-Op if otherwise
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if attn_weights.dtype != torch.float32:
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raise RuntimeError("Error with upcasting, attn_weights does not have dtype torch.float32")
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attn_weights = attn_weights.type(value.dtype)
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attn_weights = self.attn_dropout(attn_weights)
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# Mask heads if we want to
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if head_mask is not None:
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attn_weights = attn_weights * head_mask
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attn_output = torch.matmul(attn_weights, value)
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return attn_output, attn_weights
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def _split_heads(self, tensor, num_heads, attn_head_size):
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"""
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Splits hidden_size dim into attn_head_size and num_heads
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"""
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new_shape = tensor.size()[:-1] + (num_heads, attn_head_size)
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tensor = tensor.view(new_shape)
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return tensor.permute(0, 2, 1, 3) # (batch, head, seq_length, head_features)
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def _merge_heads(self, tensor, num_heads, attn_head_size):
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"""
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Merges attn_head_size dim and num_attn_heads dim into hidden_size
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"""
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tensor = tensor.permute(0, 2, 1, 3).contiguous()
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new_shape = tensor.size()[:-2] + (num_heads * attn_head_size,)
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return tensor.view(new_shape)
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def forward(
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self,
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hidden_states: Optional[Tuple[torch.FloatTensor]],
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layer_past: Optional[Tuple[torch.Tensor]] = None,
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attention_mask: Optional[torch.FloatTensor] = None,
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head_mask: Optional[torch.FloatTensor] = None,
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encoder_hidden_states: Optional[torch.Tensor] = None,
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encoder_attention_mask: Optional[torch.FloatTensor] = None,
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use_cache: Optional[bool] = False,
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output_attentions: Optional[bool] = False,
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position_bias: Optional[torch.FloatTensor] = None,
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) -> Tuple[Union[torch.Tensor, Tuple[torch.Tensor]], ...]:
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if encoder_hidden_states is not None:
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if not hasattr(self, "q_attn"):
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raise ValueError(
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"If class is used as cross attention, the weights `q_attn` have to be defined. "
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"Please make sure to instantiate class with `JAISAttention(..., is_cross_attention=True)`."
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)
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query = self.q_attn(hidden_states)
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key, value = self.c_attn(encoder_hidden_states).split(self.split_size, dim=2)
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attention_mask = encoder_attention_mask
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else:
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query, key, value = self.c_attn(hidden_states).split(self.split_size, dim=2)
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query = self._split_heads(query, self.num_heads, self.head_dim)
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key = self._split_heads(key, self.num_heads, self.head_dim)
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value = self._split_heads(value, self.num_heads, self.head_dim)
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if layer_past is not None:
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past_key, past_value = layer_past
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key = torch.cat((past_key, key), dim=-2)
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value = torch.cat((past_value, value), dim=-2)
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if use_cache is True:
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present = (key, value)
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else:
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present = None
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if self.reorder_and_upcast_attn:
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attn_output, attn_weights = self._upcast_and_reordered_attn(
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query, key, value, attention_mask, head_mask, position_bias
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)
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else:
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attn_output, attn_weights = self._attn(query, key, value, attention_mask, head_mask, position_bias)
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attn_output = self._merge_heads(attn_output, self.num_heads, self.head_dim)
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attn_output = self.c_proj(attn_output)
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attn_output = self.resid_dropout(attn_output)
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outputs = (attn_output, present)
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if output_attentions:
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outputs += (attn_weights,)
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return outputs # a, present, (attentions)
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class JAISMLP(nn.Module):
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def __init__(self, intermediate_size, config):
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super().__init__()
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embed_dim = config.hidden_size
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self.swiglu = config.activation_function == "swiglu"
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self.c_fc = Conv1D(intermediate_size, embed_dim)
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self.c_fc2 = Conv1D(intermediate_size, embed_dim) if self.swiglu else None
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self.c_proj = Conv1D(embed_dim, intermediate_size)
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self.act = SwiGLUActivation() if self.swiglu else ACT2FN[config.activation_function]
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self.dropout = nn.Dropout(config.resid_pdrop)
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def forward(self, hidden_states: Optional[Tuple[torch.FloatTensor]]) -> torch.FloatTensor:
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if self.swiglu:
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hidden_states2 = self.c_fc2(hidden_states)
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hidden_states = self.c_fc(hidden_states)
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hidden_states = self.act(hidden_states, hidden_states2) if self.swiglu else self.act(hidden_states)
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hidden_states = self.c_proj(hidden_states)
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hidden_states = self.dropout(hidden_states)
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return hidden_states
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class JAISBlock(nn.Module):
|
|
def __init__(self, config, layer_idx=None):
|
|
super().__init__()
|
|
hidden_size = config.hidden_size
|
|
inner_dim = config.n_inner if config.n_inner is not None else 4 * hidden_size
|
|
|
|
self.ln_1 = nn.LayerNorm(hidden_size, eps=config.layer_norm_epsilon)
|
|
self.attn = JAISAttention(config, layer_idx=layer_idx)
|
|
self.ln_2 = nn.LayerNorm(hidden_size, eps=config.layer_norm_epsilon)
|
|
|
|
if config.add_cross_attention:
|
|
self.crossattention = JAISAttention(config, is_cross_attention=True, layer_idx=layer_idx)
|
|
self.ln_cross_attn = nn.LayerNorm(hidden_size, eps=config.layer_norm_epsilon)
|
|
|
|
self.mlp = JAISMLP(inner_dim, config)
|
|
|
|
def forward(
|
|
self,
|
|
hidden_states: Optional[Tuple[torch.FloatTensor]],
|
|
layer_past: Optional[Tuple[torch.Tensor]] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
encoder_hidden_states: Optional[torch.Tensor] = None,
|
|
encoder_attention_mask: Optional[torch.FloatTensor] = None,
|
|
use_cache: Optional[bool] = False,
|
|
output_attentions: Optional[bool] = False,
|
|
position_bias: Optional[torch.FloatTensor] = None,
|
|
) -> Union[Tuple[torch.Tensor], Optional[Tuple[torch.Tensor, Tuple[torch.FloatTensor, ...]]]]:
|
|
residual = hidden_states
|
|
hidden_states = self.ln_1(hidden_states)
|
|
attn_outputs = self.attn(
|
|
hidden_states,
|
|
layer_past=layer_past,
|
|
attention_mask=attention_mask,
|
|
head_mask=head_mask,
|
|
use_cache=use_cache,
|
|
output_attentions=output_attentions,
|
|
position_bias=position_bias,
|
|
)
|
|
attn_output = attn_outputs[0] # output_attn: a, present, (attentions)
|
|
outputs = attn_outputs[1:]
|
|
# residual connection
|
|
hidden_states = attn_output + residual
|
|
|
|
if encoder_hidden_states is not None:
|
|
# add one self-attention block for cross-attention
|
|
if not hasattr(self, "crossattention"):
|
|
raise ValueError(
|
|
f"If `encoder_hidden_states` are passed, {self} has to be instantiated with "
|
|
"cross-attention layers by setting `config.add_cross_attention=True`"
|
|
)
|
|
residual = hidden_states
|
|
hidden_states = self.ln_cross_attn(hidden_states)
|
|
cross_attn_outputs = self.crossattention(
|
|
hidden_states,
|
|
attention_mask=attention_mask,
|
|
head_mask=head_mask,
|
|
encoder_hidden_states=encoder_hidden_states,
|
|
encoder_attention_mask=encoder_attention_mask,
|
|
output_attentions=output_attentions,
|
|
position_bias=position_bias,
|
|
)
|
|
attn_output = cross_attn_outputs[0]
|
|
# residual connection
|
|
hidden_states = residual + attn_output
|
|
outputs = outputs + cross_attn_outputs[2:] # add cross attentions if we output attention weights
|
|
|
|
residual = hidden_states
|
|
hidden_states = self.ln_2(hidden_states)
|
|
feed_forward_hidden_states = self.mlp(hidden_states)
|
|
# residual connection
|
|
hidden_states = residual + feed_forward_hidden_states
|
|
|
|
if use_cache:
|
|
outputs = (hidden_states,) + outputs
|
|
else:
|
|
outputs = (hidden_states,) + outputs[1:]
|
|
|
|
return outputs # hidden_states, present, (attentions, cross_attentions)
|
|
|
|
|
|
class JAISPreTrainedModel(PreTrainedModel):
|
|
"""
|
|
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
|
|
models.
|
|
"""
|
|
|
|
config_class = JAISConfig
|
|
load_tf_weights = load_tf_weights_in_jais
|
|
base_model_prefix = "transformer"
|
|
is_parallelizable = True
|
|
supports_gradient_checkpointing = True
|
|
_no_split_modules = ["JAISBlock"]
|
|
_skip_keys_device_placement = "past_key_values"
|
|
|
|
def __init__(self, *inputs, **kwargs):
|
|
super().__init__(*inputs, **kwargs)
|
|
|
|
def _init_weights(self, module):
|
|
"""Initialize the weights."""
|
|
mup_init_scale = math.sqrt(self.config.mup_width_scale)
|
|
if isinstance(module, (nn.Linear, Conv1D)):
|
|
# Slightly different from the TF version which uses truncated_normal for initialization
|
|
# cf https://github.com/pytorch/pytorch/pull/5617
|
|
module.weight.data.normal_(mean=0.0, std=(self.config.initializer_range * mup_init_scale))
|
|
if module.bias is not None:
|
|
module.bias.data.zero_()
|
|
elif isinstance(module, nn.Embedding):
|
|
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
|
|
if module.padding_idx is not None:
|
|
module.weight.data[module.padding_idx].zero_()
|
|
elif isinstance(module, nn.LayerNorm):
|
|
module.bias.data.zero_()
|
|
module.weight.data.fill_(1.0)
|
|
|
|
# Reinitialize selected weights subject to the OpenAI GPT-2 Paper Scheme:
|
|
# > A modified initialization which accounts for the accumulation on the residual path with model depth. Scale
|
|
# > the weights of residual layers at initialization by a factor of 1/√N where N is the # of residual layers.
|
|
# > -- GPT-2 :: https://openai.com/blog/better-language-models/
|
|
#
|
|
# Reference (Megatron-LM): https://github.com/NVIDIA/Megatron-LM/blob/main/megatron/model/gpt_model.py
|
|
for name, p in module.named_parameters():
|
|
if name == "c_proj.weight":
|
|
# Special Scaled Initialization --> There are 2 Layer Norms per Transformer Block
|
|
stddev = self.config.initializer_range * mup_init_scale / math.sqrt(2 * self.config.n_layer)
|
|
p.data.normal_(mean=0.0, std=stddev)
|
|
|
|
def _set_gradient_checkpointing(self, module, value=False):
|
|
if isinstance(module, JAISModel):
|
|
module.gradient_checkpointing = value
|
|
|
|
def get_mup_param_groups(self, lr, weight_decay=0.0, decoupled_wd=True):
|
|
"""
|
|
Returns list of dicts defining parameter groups for muP:
|
|
group 0: most model params get scaled learning rate and weight decay.
|
|
group 1: embedding layer gets non-scaled learning rate and weight decay.
|
|
group 2: normalization layers and biases get non-scaled learning rate only.
|
|
|
|
The output can be passed to Adam-base optimizers
|
|
e.g.
|
|
param_groups = model.get_mup_param_groups(lr=1e-3, weight_decay=0.1)
|
|
torch.optim.AdamW(param_groups, betas=(0.9, 0.95), eps=1e-8)
|
|
"""
|
|
norm_modules = (
|
|
torch.nn.LayerNorm,
|
|
torch.nn.BatchNorm1d,
|
|
torch.nn.BatchNorm2d,
|
|
torch.nn.BatchNorm3d,
|
|
torch.nn.InstanceNorm1d,
|
|
torch.nn.InstanceNorm2d,
|
|
torch.nn.InstanceNorm3d,
|
|
torch.nn.GroupNorm,
|
|
torch.nn.SyncBatchNorm,
|
|
torch.nn.LocalResponseNorm,
|
|
)
|
|
|
|
def get_group_index(param_name):
|
|
for name, module in self.named_modules():
|
|
if name in param_name:
|
|
if isinstance(module, norm_modules):
|
|
return 2
|
|
elif isinstance(module, torch.nn.Embedding):
|
|
return 1
|
|
return 0
|
|
|
|
width_scale = self.config.mup_width_scale
|
|
new_param_groups = []
|
|
new_param_groups.append({"params": [], "lr": lr * width_scale, "weight_decay": weight_decay})
|
|
if not decoupled_wd:
|
|
new_param_groups[0]["weight_decay"] /= width_scale
|
|
new_param_groups.append({"params": [], "lr": lr, "weight_decay": weight_decay})
|
|
new_param_groups.append({"params": [], "lr": lr, "weight_decay": 0.0})
|
|
|
|
for name, param in self.named_parameters():
|
|
if not param.requires_grad:
|
|
continue
|
|
|
|
if name.endswith("bias"):
|
|
new_param_groups[2]["params"].append(param)
|
|
else:
|
|
new_param_groups[get_group_index(name)]["params"].append(param)
|
|
|
|
for idx, param_group in enumerate(new_param_groups):
|
|
if len(param_group["params"]) == 0:
|
|
del new_param_groups[idx]
|
|
|
|
return new_param_groups
|
|
|
|
|
|
JAIS_START_DOCSTRING = r"""
|
|
|
|
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 ([`JAISConfig`]): 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.
|
|
"""
|
|
|
|
JAIS_INPUTS_DOCSTRING = r"""
|
|
Args:
|
|
input_ids (`torch.LongTensor` of shape `(batch_size, input_ids_length)`):
|
|
`input_ids_length` = `sequence_length` if `past_key_values` is `None` else
|
|
`past_key_values[0][0].shape[-2]` (`sequence_length` of input past key value states). Indices of input
|
|
sequence tokens in the vocabulary.
|
|
|
|
If `past_key_values` is used, only `input_ids` that do not have their past calculated should be passed as
|
|
`input_ids`.
|
|
|
|
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
|
|
[`PreTrainedTokenizer.__call__`] for details.
|
|
|
|
[What are input IDs?](../glossary#input-ids)
|
|
past_key_values (`Tuple[Tuple[torch.Tensor]]` of length `config.n_layers`):
|
|
Contains precomputed hidden-states (key and values in the attention blocks) as computed by the model (see
|
|
`past_key_values` output below). Can be used to speed up sequential decoding. The `input_ids` which have
|
|
their past given to this model should not be passed as `input_ids` as they have already been computed.
|
|
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**.
|
|
|
|
If `past_key_values` is used, `attention_mask` needs to contain the masking strategy that was used for
|
|
`past_key_values`. In other words, the `attention_mask` always has to have the length:
|
|
`len(past_key_values) + len(input_ids)`
|
|
|
|
[What are attention masks?](../glossary#attention-mask)
|
|
token_type_ids (`torch.LongTensor` of shape `(batch_size, input_ids_length)`, *optional*):
|
|
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,
|
|
1]`:
|
|
|
|
- 0 corresponds to a *sentence A* token,
|
|
- 1 corresponds to a *sentence B* token.
|
|
|
|
[What are token type IDs?](../glossary#token-type-ids)
|
|
position_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
|
|
Indices of positions of each input sequence tokens in the position embeddings. Selected in the range `[0,
|
|
config.max_position_embeddings - 1]`.
|
|
|
|
[What are position IDs?](../glossary#position-ids)
|
|
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.
|
|
|
|
If `past_key_values` is used, optionally only the last `inputs_embeds` have to be input (see
|
|
`past_key_values`).
|
|
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.
|
|
"""
|
|
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 gpt2 models have the
|
|
following number of attention modules:
|
|
|
|
- gpt2: 12
|
|
- gpt2-medium: 24
|
|
- gpt2-large: 36
|
|
- gpt2-xl: 48
|
|
|
|
Example:
|
|
|
|
```python
|
|
# Here is an example of a device map on a machine with 4 GPUs using gpt2-xl, which has a total of 48 attention modules:
|
|
model = GPT2LMHeadModel.from_pretrained("gpt2-xl")
|
|
device_map = {
|
|
0: [0, 1, 2, 3, 4, 5, 6, 7, 8],
|
|
1: [9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21],
|
|
2: [22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34],
|
|
3: [35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47],
|
|
}
|
|
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 gpt2-large:
|
|
model = GPT2LMHeadModel.from_pretrained("gpt2-large")
|
|
device_map = {
|
|
0: [0, 1, 2, 3, 4, 5, 6, 7],
|
|
1: [8, 9, 10, 11, 12, 13, 14, 15],
|
|
2: [16, 17, 18, 19, 20, 21, 22, 23],
|
|
3: [24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35],
|
|
}
|
|
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()
|
|
```
|
|
"""
|
|
|
|
|
|
@add_start_docstrings(
|
|
"The bare JAIS Model transformer outputting raw hidden-states without any specific head on top.",
|
|
JAIS_START_DOCSTRING,
|
|
)
|
|
class JAISModel(JAISPreTrainedModel):
|
|
_keys_to_ignore_on_load_unexpected = [r"h\.\d+\.attn\.bias", r"h\.\d+\.attn\.masked_bias"]
|
|
_keys_to_ignore_on_load_missing = [r"attn.masked_bias", r"h\.\d+\.attn\.masked_bias", r"h\.\d+\.attn\.bias"]
|
|
|
|
def __init__(self, config):
|
|
super().__init__(config)
|
|
|
|
self.embed_dim = config.hidden_size
|
|
|
|
self.wte = nn.Embedding(config.vocab_size, self.embed_dim)
|
|
self.wpe = (
|
|
nn.Embedding(config.max_position_embeddings, self.embed_dim)
|
|
if config.position_embedding_type != "alibi"
|
|
else None
|
|
)
|
|
self.embeddings_scale = config.mup_embeddings_scale
|
|
|
|
self.drop = nn.Dropout(config.embd_pdrop)
|
|
self.h = nn.ModuleList([JAISBlock(config, layer_idx=i) for i in range(config.num_hidden_layers)])
|
|
self.ln_f = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_epsilon)
|
|
|
|
self.relative_pe = (
|
|
AlibiPositionEmbeddingLayer(config.num_attention_heads, config.alibi_scaling)
|
|
if config.position_embedding_type == "alibi"
|
|
else None
|
|
)
|
|
|
|
# Model parallel
|
|
self.model_parallel = False
|
|
self.device_map = None
|
|
self.gradient_checkpointing = False
|
|
|
|
# Initialize weights and apply final processing
|
|
self.post_init()
|
|
|
|
@add_start_docstrings(PARALLELIZE_DOCSTRING)
|
|
def parallelize(self, device_map=None):
|
|
# Check validity of device_map
|
|
warnings.warn(
|
|
"`JAISModel.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 {'h.0': 0, 'h.1': 1,"
|
|
" ...}",
|
|
FutureWarning,
|
|
)
|
|
self.device_map = (
|
|
get_device_map(len(self.h), range(torch.cuda.device_count())) if device_map is None else device_map
|
|
)
|
|
assert_device_map(self.device_map, len(self.h))
|
|
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()))
|
|
self.wte = self.wte.to(self.first_device)
|
|
if self.wpe is not None:
|
|
self.wpe = self.wpe.to(self.first_device)
|
|
# Load onto devices
|
|
for k, v in self.device_map.items():
|
|
for block in v:
|
|
cuda_device = "cuda:" + str(k)
|
|
self.h[block] = self.h[block].to(cuda_device)
|
|
# ln_f to last
|
|
self.ln_f = self.ln_f.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"
|
|
self.wte = self.wte.to("cpu")
|
|
if self.wpe is not None:
|
|
self.wpe = self.wpe.to("cpu")
|
|
for index in range(len(self.h)):
|
|
self.h[index] = self.h[index].to("cpu")
|
|
self.ln_f = self.ln_f.to("cpu")
|
|
torch.cuda.empty_cache()
|
|
|
|
def get_input_embeddings(self):
|
|
return self.wte
|
|
|
|
def set_input_embeddings(self, new_embeddings):
|
|
self.wte = new_embeddings
|
|
|
|
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}
|
|
"""
|
|
for layer, heads in heads_to_prune.items():
|
|
self.h[layer].attn.prune_heads(heads)
|
|
|
|
@add_start_docstrings_to_model_forward(JAIS_INPUTS_DOCSTRING)
|
|
@add_code_sample_docstrings(
|
|
checkpoint=_CHECKPOINT_FOR_DOC,
|
|
output_type=BaseModelOutputWithPastAndCrossAttentions,
|
|
config_class=_CONFIG_FOR_DOC,
|
|
)
|
|
def forward(
|
|
self,
|
|
input_ids: Optional[torch.LongTensor] = None,
|
|
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
token_type_ids: Optional[torch.LongTensor] = None,
|
|
position_ids: Optional[torch.LongTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
inputs_embeds: Optional[torch.FloatTensor] = None,
|
|
encoder_hidden_states: Optional[torch.Tensor] = None,
|
|
encoder_attention_mask: Optional[torch.FloatTensor] = None,
|
|
use_cache: Optional[bool] = None,
|
|
output_attentions: Optional[bool] = None,
|
|
output_hidden_states: Optional[bool] = None,
|
|
return_dict: Optional[bool] = None,
|
|
) -> Union[Tuple, BaseModelOutputWithPastAndCrossAttentions]:
|
|
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
|
|
)
|
|
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
|
|
|
|
if input_ids is not None and inputs_embeds is not None:
|
|
raise ValueError("You cannot specify both input_ids and 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])
|
|
batch_size = input_ids.shape[0]
|
|
elif inputs_embeds is not None:
|
|
input_shape = inputs_embeds.size()[:-1]
|
|
batch_size = inputs_embeds.shape[0]
|
|
else:
|
|
raise ValueError("You have to specify either input_ids or inputs_embeds")
|
|
|
|
device = input_ids.device if input_ids is not None else inputs_embeds.device
|
|
|
|
if token_type_ids is not None:
|
|
token_type_ids = token_type_ids.view(-1, input_shape[-1])
|
|
if position_ids is not None:
|
|
position_ids = position_ids.view(-1, input_shape[-1])
|
|
|
|
if past_key_values is None:
|
|
past_length = 0
|
|
past_key_values = tuple([None] * len(self.h))
|
|
else:
|
|
past_length = past_key_values[0][0].size(-2)
|
|
if position_ids is None:
|
|
position_ids = torch.arange(past_length, input_shape[-1] + past_length, dtype=torch.long, device=device)
|
|
position_ids = position_ids.unsqueeze(0).view(-1, input_shape[-1])
|
|
|
|
# JAISAttention mask.
|
|
if attention_mask is not None:
|
|
if batch_size <= 0:
|
|
raise ValueError("batch_size has to be defined and > 0")
|
|
attention_mask = attention_mask.view(batch_size, -1)
|
|
# We create a 3D attention mask from a 2D tensor mask.
|
|
# Sizes are [batch_size, 1, 1, to_seq_length]
|
|
# So we can broadcast to [batch_size, num_heads, from_seq_length, to_seq_length]
|
|
# this attention mask is more simple than the triangular masking of causal attention
|
|
# used in OpenAI GPT, we just need to prepare the broadcast dimension here.
|
|
attention_mask = attention_mask[:, None, None, :]
|
|
|
|
# Since attention_mask is 1.0 for positions we want to attend and 0.0 for
|
|
# masked positions, this operation will create a tensor which is 0.0 for
|
|
# positions we want to attend and the dtype's smallest value for masked positions.
|
|
# Since we are adding it to the raw scores before the softmax, this is
|
|
# effectively the same as removing these entirely.
|
|
attention_mask = attention_mask.to(dtype=self.dtype) # fp16 compatibility
|
|
attention_mask = (1.0 - attention_mask) * torch.finfo(self.dtype).min
|
|
|
|
# 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.config.add_cross_attention 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=device)
|
|
encoder_attention_mask = self.invert_attention_mask(encoder_attention_mask)
|
|
else:
|
|
encoder_attention_mask = None
|
|
|
|
# Prepare head mask if needed
|
|
# 1.0 in head_mask indicate we keep the head
|
|
# attention_probs has shape bsz x n_heads x N x N
|
|
# head_mask has shape n_layer x batch x n_heads x N x N
|
|
head_mask = self.get_head_mask(head_mask, self.config.n_layer)
|
|
|
|
if inputs_embeds is None:
|
|
inputs_embeds = self.wte(input_ids)
|
|
if self.wpe is not None:
|
|
position_embeds = self.wpe(position_ids)
|
|
hidden_states = inputs_embeds + position_embeds
|
|
else:
|
|
hidden_states = inputs_embeds
|
|
hidden_states *= torch.tensor(
|
|
float(self.embeddings_scale), dtype=hidden_states.dtype, device=hidden_states.device
|
|
)
|
|
|
|
if token_type_ids is not None:
|
|
token_type_embeds = self.wte(token_type_ids)
|
|
hidden_states = hidden_states + token_type_embeds
|
|
|
|
hidden_states = self.drop(hidden_states)
|
|
|
|
if self.relative_pe is not None:
|
|
length = input_ids.shape[1]
|
|
cached_kv_length = 0
|
|
cached_kv = past_key_values[0]
|
|
if cached_kv is not None:
|
|
cached_kv_length = cached_kv[0].shape[-2]
|
|
position_bias = self.relative_pe(length, length, cached_kv_length)
|
|
else:
|
|
position_bias = None
|
|
|
|
output_shape = input_shape + (hidden_states.size(-1),)
|
|
|
|
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
|
|
|
|
presents = () if use_cache else None
|
|
all_self_attentions = () if output_attentions else None
|
|
all_cross_attentions = () if output_attentions and self.config.add_cross_attention else None
|
|
all_hidden_states = () if output_hidden_states else None
|
|
for i, (block, layer_past) in enumerate(zip(self.h, past_key_values)):
|
|
# Model parallel
|
|
if self.model_parallel:
|
|
torch.cuda.set_device(hidden_states.device)
|
|
# Ensure layer_past is on same device as hidden_states (might not be correct)
|
|
if layer_past is not None:
|
|
layer_past = tuple(past_state.to(hidden_states.device) for past_state in layer_past)
|
|
# 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 isinstance(head_mask, torch.Tensor):
|
|
head_mask = 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):
|
|
# None for past_key_value
|
|
return module(*inputs, use_cache, output_attentions)
|
|
|
|
return custom_forward
|
|
|
|
outputs = torch.utils.checkpoint.checkpoint(
|
|
create_custom_forward(block),
|
|
hidden_states,
|
|
None,
|
|
attention_mask,
|
|
head_mask[i],
|
|
encoder_hidden_states,
|
|
encoder_attention_mask,
|
|
)
|
|
else:
|
|
outputs = block(
|
|
hidden_states,
|
|
layer_past=layer_past,
|
|
attention_mask=attention_mask,
|
|
head_mask=head_mask[i],
|
|
encoder_hidden_states=encoder_hidden_states,
|
|
encoder_attention_mask=encoder_attention_mask,
|
|
use_cache=use_cache,
|
|
output_attentions=output_attentions,
|
|
position_bias=position_bias,
|
|
)
|
|
|
|
hidden_states = outputs[0]
|
|
if use_cache is True:
|
|
presents = presents + (outputs[1],)
|
|
|
|
if output_attentions:
|
|
all_self_attentions = all_self_attentions + (outputs[2 if use_cache else 1],)
|
|
if self.config.add_cross_attention:
|
|
all_cross_attentions = all_cross_attentions + (outputs[3 if use_cache else 2],)
|
|
|
|
# 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.ln_f(hidden_states)
|
|
|
|
hidden_states = hidden_states.view(output_shape)
|
|
# Add last hidden state
|
|
if output_hidden_states:
|
|
all_hidden_states = all_hidden_states + (hidden_states,)
|
|
|
|
if not return_dict:
|
|
return tuple(
|
|
v
|
|
for v in [hidden_states, presents, all_hidden_states, all_self_attentions, all_cross_attentions]
|
|
if v is not None
|
|
)
|
|
|
|
return BaseModelOutputWithPastAndCrossAttentions(
|
|
last_hidden_state=hidden_states,
|
|
past_key_values=presents,
|
|
hidden_states=all_hidden_states,
|
|
attentions=all_self_attentions,
|
|
cross_attentions=all_cross_attentions,
|
|
)
|
|
|
|
|
|
@add_start_docstrings(
|
|
"""
|
|
The JAIS Model transformer with a language modeling head on top (linear layer with weights tied to the input
|
|
embeddings).
|
|
""",
|
|
JAIS_START_DOCSTRING,
|
|
)
|
|
class JAISLMHeadModel(JAISPreTrainedModel):
|
|
_keys_to_ignore_on_load_missing = [r"lm_head.weight"]
|
|
_keys_to_ignore_on_load_unexpected = [r"h\.\d+\.attn\.masked_bias", r"h\.\d+\.attn\.bias"]
|
|
|
|
def __init__(self, config):
|
|
super().__init__(config)
|
|
self.transformer = JAISModel(config)
|
|
self.lm_head = nn.Linear(config.n_embd, config.vocab_size, bias=False)
|
|
self.output_logits_scale = config.mup_output_alpha * config.mup_width_scale
|
|
|
|
# Model parallel
|
|
self.model_parallel = False
|
|
self.device_map = None
|
|
|
|
# Initialize weights and apply final processing
|
|
self.post_init()
|
|
|
|
@add_start_docstrings(PARALLELIZE_DOCSTRING)
|
|
def parallelize(self, device_map=None):
|
|
warnings.warn(
|
|
"`JAISLMHeadModel.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 {'transformer.h.0':"
|
|
" 0, 'transformer.h.1': 1, ...}",
|
|
FutureWarning,
|
|
)
|
|
self.device_map = (
|
|
get_device_map(len(self.transformer.h), range(torch.cuda.device_count()))
|
|
if device_map is None
|
|
else device_map
|
|
)
|
|
assert_device_map(self.device_map, len(self.transformer.h))
|
|
self.transformer.parallelize(self.device_map)
|
|
self.lm_head = self.lm_head.to(self.transformer.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.transformer.deparallelize()
|
|
self.transformer = self.transformer.to("cpu")
|
|
self.lm_head = self.lm_head.to("cpu")
|
|
self.model_parallel = False
|
|
torch.cuda.empty_cache()
|
|
|
|
def get_output_embeddings(self):
|
|
return self.lm_head
|
|
|
|
def set_output_embeddings(self, new_embeddings):
|
|
self.lm_head = new_embeddings
|
|
|
|
def prepare_inputs_for_generation(self, input_ids, past_key_values=None, inputs_embeds=None, **kwargs):
|
|
token_type_ids = kwargs.get("token_type_ids", None)
|
|
# only last token for inputs_ids if past is defined in kwargs
|
|
if past_key_values:
|
|
input_ids = input_ids[:, -1].unsqueeze(-1)
|
|
if token_type_ids is not None:
|
|
token_type_ids = token_type_ids[:, -1].unsqueeze(-1)
|
|
|
|
attention_mask = kwargs.get("attention_mask", None)
|
|
position_ids = kwargs.get("position_ids", None)
|
|
|
|
if attention_mask is not None and position_ids is None:
|
|
# create position_ids on the fly for batch generation
|
|
position_ids = attention_mask.long().cumsum(-1) - 1
|
|
position_ids.masked_fill_(attention_mask == 0, 1)
|
|
if past_key_values:
|
|
position_ids = position_ids[:, -1].unsqueeze(-1)
|
|
else:
|
|
position_ids = None
|
|
|
|
# if `inputs_embeds` are passed, we only want to use them in the 1st generation step
|
|
if inputs_embeds is not None and past_key_values is None:
|
|
model_inputs = {"inputs_embeds": inputs_embeds}
|
|
else:
|
|
model_inputs = {"input_ids": input_ids}
|
|
|
|
model_inputs.update(
|
|
{
|
|
"past_key_values": past_key_values,
|
|
"use_cache": kwargs.get("use_cache"),
|
|
"position_ids": position_ids,
|
|
"attention_mask": attention_mask,
|
|
"token_type_ids": token_type_ids,
|
|
}
|
|
)
|
|
return model_inputs
|
|
|
|
@add_start_docstrings_to_model_forward(JAIS_INPUTS_DOCSTRING)
|
|
@add_code_sample_docstrings(
|
|
checkpoint=_CHECKPOINT_FOR_DOC,
|
|
output_type=CausalLMOutputWithCrossAttentions,
|
|
config_class=_CONFIG_FOR_DOC,
|
|
)
|
|
def forward(
|
|
self,
|
|
input_ids: Optional[torch.LongTensor] = None,
|
|
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
token_type_ids: Optional[torch.LongTensor] = None,
|
|
position_ids: Optional[torch.LongTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
inputs_embeds: Optional[torch.FloatTensor] = None,
|
|
encoder_hidden_states: Optional[torch.Tensor] = None,
|
|
encoder_attention_mask: 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,
|
|
) -> Union[Tuple, CausalLMOutputWithCrossAttentions]:
|
|
r"""
|
|
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
|
|
Labels for language modeling. Note that the labels **are shifted** inside the model, i.e. you can set
|
|
`labels = input_ids` Indices are selected in `[-100, 0, ..., config.vocab_size]` All labels set to `-100`
|
|
are ignored (masked), the loss is only computed for labels in `[0, ..., config.vocab_size]`
|
|
"""
|
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
|
|
|
transformer_outputs = self.transformer(
|
|
input_ids,
|
|
past_key_values=past_key_values,
|
|
attention_mask=attention_mask,
|
|
token_type_ids=token_type_ids,
|
|
position_ids=position_ids,
|
|
head_mask=head_mask,
|
|
inputs_embeds=inputs_embeds,
|
|
encoder_hidden_states=encoder_hidden_states,
|
|
encoder_attention_mask=encoder_attention_mask,
|
|
use_cache=use_cache,
|
|
output_attentions=output_attentions,
|
|
output_hidden_states=output_hidden_states,
|
|
return_dict=return_dict,
|
|
)
|
|
hidden_states = transformer_outputs[0]
|
|
|
|
# Set device for model parallelism
|
|
if self.model_parallel:
|
|
torch.cuda.set_device(self.transformer.first_device)
|
|
hidden_states = hidden_states.to(self.lm_head.weight.device)
|
|
|
|
lm_logits = self.lm_head(hidden_states)
|
|
lm_logits *= torch.tensor(float(self.output_logits_scale), dtype=lm_logits.dtype, device=lm_logits.device)
|
|
|
|
loss = None
|
|
if labels is not None:
|
|
# move labels to correct device to enable model parallelism
|
|
labels = labels.to(lm_logits.device)
|
|
# Shift so that tokens < n predict n
|
|
shift_logits = lm_logits[..., :-1, :].contiguous()
|
|
shift_labels = labels[..., 1:].contiguous()
|
|
# Flatten the tokens
|
|
loss_fct = CrossEntropyLoss()
|
|
loss = loss_fct(shift_logits.view(-1, shift_logits.size(-1)), shift_labels.view(-1))
|
|
|
|
if not return_dict:
|
|
output = (lm_logits,) + transformer_outputs[1:]
|
|
return ((loss,) + output) if loss is not None else output
|
|
|
|
return CausalLMOutputWithCrossAttentions(
|
|
loss=loss,
|
|
logits=lm_logits,
|
|
past_key_values=transformer_outputs.past_key_values,
|
|
hidden_states=transformer_outputs.hidden_states,
|
|
attentions=transformer_outputs.attentions,
|
|
cross_attentions=transformer_outputs.cross_attentions,
|
|
)
|
|
|
|
@staticmethod
|
|
def _reorder_cache(
|
|
past_key_values: Tuple[Tuple[torch.Tensor]], beam_idx: torch.Tensor
|
|
) -> Tuple[Tuple[torch.Tensor]]:
|
|
"""
|
|
This function is used to re-order the `past_key_values` cache if [`~PreTrainedModel.beam_search`] or
|
|
[`~PreTrainedModel.beam_sample`] is called. This is required to match `past_key_values` with the correct
|
|
beam_idx at every generation step.
|
|
"""
|
|
return tuple(
|
|
tuple(past_state.index_select(0, beam_idx.to(past_state.device)) for past_state in layer_past)
|
|
for layer_past in past_key_values
|
|
)
|
|
|
|
|
|
@add_start_docstrings(
|
|
"""
|
|
The JAIS Model transformer with a sequence classification head on top (linear layer).
|
|
|
|
[`JAISForSequenceClassification`] uses the last token in order to do the classification, as other causal models
|
|
(e.g. GPT-1) do.
|
|
|
|
Since it does classification on the last token, it requires to know the position of the last token. If a
|
|
`pad_token_id` is defined in the configuration, it finds the last token that is not a padding token in each row. If
|
|
no `pad_token_id` is defined, it simply takes the last value in each row of the batch. Since it cannot guess the
|
|
padding tokens when `inputs_embeds` are passed instead of `input_ids`, it does the same (take the last value in
|
|
each row of the batch).
|
|
""",
|
|
JAIS_START_DOCSTRING,
|
|
)
|
|
class JAISForSequenceClassification(JAISPreTrainedModel):
|
|
_keys_to_ignore_on_load_unexpected = [r"h\.\d+\.attn\.bias", r"h\.\d+\.attn\.masked_bias"]
|
|
_keys_to_ignore_on_load_missing = [r"h\.\d+\.attn\.masked_bias", r"lm_head.weight"]
|
|
|
|
def __init__(self, config):
|
|
super().__init__(config)
|
|
self.num_labels = config.num_labels
|
|
self.transformer = JAISModel(config)
|
|
self.score = nn.Linear(config.n_embd, self.num_labels, bias=False)
|
|
self.output_logits_scale = config.mup_output_alpha * config.mup_width_scale
|
|
|
|
# Model parallel
|
|
self.model_parallel = False
|
|
self.device_map = None
|
|
|
|
# Initialize weights and apply final processing
|
|
self.post_init()
|
|
|
|
@add_start_docstrings_to_model_forward(JAIS_INPUTS_DOCSTRING)
|
|
@add_code_sample_docstrings(
|
|
checkpoint="microsoft/DialogRPT-updown",
|
|
output_type=SequenceClassifierOutputWithPast,
|
|
config_class=_CONFIG_FOR_DOC,
|
|
)
|
|
def forward(
|
|
self,
|
|
input_ids: Optional[torch.LongTensor] = None,
|
|
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
token_type_ids: Optional[torch.LongTensor] = None,
|
|
position_ids: Optional[torch.LongTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
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,
|
|
) -> Union[Tuple, SequenceClassifierOutputWithPast]:
|
|
r"""
|
|
labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
|
|
Labels for computing the sequence classification/regression loss. Indices should be in `[0, ...,
|
|
config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
|
|
`config.num_labels > 1` a classification loss is computed (Cross-Entropy).
|
|
"""
|
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
|
|
|
transformer_outputs = self.transformer(
|
|
input_ids,
|
|
past_key_values=past_key_values,
|
|
attention_mask=attention_mask,
|
|
token_type_ids=token_type_ids,
|
|
position_ids=position_ids,
|
|
head_mask=head_mask,
|
|
inputs_embeds=inputs_embeds,
|
|
use_cache=use_cache,
|
|
output_attentions=output_attentions,
|
|
output_hidden_states=output_hidden_states,
|
|
return_dict=return_dict,
|
|
)
|
|
hidden_states = transformer_outputs[0]
|
|
logits = self.score(hidden_states)
|
|
logits *= torch.tensor(float(self.output_logits_scale), dtype=logits.dtype, device=logits.device)
|
|
|
|
if input_ids is not None:
|
|
batch_size, sequence_length = input_ids.shape[:2]
|
|
else:
|
|
batch_size, sequence_length = inputs_embeds.shape[:2]
|
|
|
|
assert (
|
|
self.config.pad_token_id is not None or batch_size == 1
|
|
), "Cannot handle batch sizes > 1 if no padding token is defined."
|
|
if self.config.pad_token_id is None:
|
|
sequence_lengths = -1
|
|
else:
|
|
if input_ids is not None:
|
|
sequence_lengths = (torch.ne(input_ids, self.config.pad_token_id).sum(-1) - 1).to(logits.device)
|
|
else:
|
|
sequence_lengths = -1
|
|
logger.warning(
|
|
f"{self.__class__.__name__} will not detect padding tokens in `inputs_embeds`. Results may be "
|
|
"unexpected if using padding tokens in conjunction with `inputs_embeds.`"
|
|
)
|
|
|
|
pooled_logits = logits[torch.arange(batch_size, device=logits.device), sequence_lengths]
|
|
|
|
loss = None
|
|
if labels is not None:
|
|
if self.config.problem_type is None:
|
|
if self.num_labels == 1:
|
|
self.config.problem_type = "regression"
|
|
elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
|
|
self.config.problem_type = "single_label_classification"
|
|
else:
|
|
self.config.problem_type = "multi_label_classification"
|
|
|
|
if self.config.problem_type == "regression":
|
|
loss_fct = MSELoss()
|
|
if self.num_labels == 1:
|
|
loss = loss_fct(pooled_logits.squeeze(), labels.squeeze())
|
|
else:
|
|
loss = loss_fct(pooled_logits, labels)
|
|
elif self.config.problem_type == "single_label_classification":
|
|
loss_fct = CrossEntropyLoss()
|
|
loss = loss_fct(pooled_logits.view(-1, self.num_labels), labels.view(-1))
|
|
elif self.config.problem_type == "multi_label_classification":
|
|
loss_fct = BCEWithLogitsLoss()
|
|
loss = loss_fct(pooled_logits, labels)
|
|
if not return_dict:
|
|
output = (pooled_logits,) + transformer_outputs[1:]
|
|
return ((loss,) + output) if loss is not None else output
|
|
|
|
return SequenceClassifierOutputWithPast(
|
|
loss=loss,
|
|
logits=pooled_logits,
|
|
past_key_values=transformer_outputs.past_key_values,
|
|
hidden_states=transformer_outputs.hidden_states,
|
|
attentions=transformer_outputs.attentions,
|
|
)
|
|
|
|
|
|
@add_start_docstrings(
|
|
"""
|
|
JAIS Model with a token classification head on top (a linear layer on top of the hidden-states output) e.g. for
|
|
Named-Entity-Recognition (NER) tasks.
|
|
""",
|
|
JAIS_START_DOCSTRING,
|
|
)
|
|
class JAISForTokenClassification(JAISPreTrainedModel):
|
|
def __init__(self, config):
|
|
super().__init__(config)
|
|
self.num_labels = config.num_labels
|
|
|
|
self.transformer = JAISModel(config)
|
|
if hasattr(config, "classifier_dropout") and config.classifier_dropout is not None:
|
|
classifier_dropout = config.classifier_dropout
|
|
elif hasattr(config, "hidden_dropout") and config.hidden_dropout is not None:
|
|
classifier_dropout = config.hidden_dropout
|
|
else:
|
|
classifier_dropout = 0.1
|
|
self.dropout = nn.Dropout(classifier_dropout)
|
|
self.classifier = nn.Linear(config.hidden_size, config.num_labels)
|
|
self.output_logits_scale = config.mup_output_alpha * config.mup_width_scale
|
|
|
|
# Model parallel
|
|
self.model_parallel = False
|
|
self.device_map = None
|
|
|
|
# Initialize weights and apply final processing
|
|
self.post_init()
|
|
|
|
@add_start_docstrings_to_model_forward(JAIS_INPUTS_DOCSTRING)
|
|
# fmt: off
|
|
@add_code_sample_docstrings(
|
|
checkpoint="brad1141/gpt2-finetuned-comp2",
|
|
output_type=TokenClassifierOutput,
|
|
config_class=_CONFIG_FOR_DOC,
|
|
expected_loss=0.25,
|
|
expected_output=["Lead", "Lead", "Lead", "Position", "Lead", "Lead", "Lead", "Lead", "Lead", "Lead", "Lead", "Lead"],
|
|
)
|
|
# fmt: on
|
|
def forward(
|
|
self,
|
|
input_ids: Optional[torch.LongTensor] = None,
|
|
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
token_type_ids: Optional[torch.LongTensor] = None,
|
|
position_ids: Optional[torch.LongTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
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,
|
|
) -> Union[Tuple, TokenClassifierOutput]:
|
|
r"""
|
|
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
|
|
Labels for computing the sequence classification/regression loss. Indices should be in `[0, ...,
|
|
config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
|
|
`config.num_labels > 1` a classification loss is computed (Cross-Entropy).
|
|
"""
|
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
|
|
|
transformer_outputs = self.transformer(
|
|
input_ids,
|
|
past_key_values=past_key_values,
|
|
attention_mask=attention_mask,
|
|
token_type_ids=token_type_ids,
|
|
position_ids=position_ids,
|
|
head_mask=head_mask,
|
|
inputs_embeds=inputs_embeds,
|
|
use_cache=use_cache,
|
|
output_attentions=output_attentions,
|
|
output_hidden_states=output_hidden_states,
|
|
return_dict=return_dict,
|
|
)
|
|
|
|
hidden_states = transformer_outputs[0]
|
|
hidden_states = self.dropout(hidden_states)
|
|
logits = self.classifier(hidden_states)
|
|
logits *= torch.tensor(float(self.output_logits_scale), dtype=logits.dtype, device=logits.device)
|
|
|
|
loss = None
|
|
if labels is not None:
|
|
labels = labels.to(logits.device)
|
|
loss_fct = CrossEntropyLoss()
|
|
loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
|
|
|
|
if not return_dict:
|
|
output = (logits,) + transformer_outputs[2:]
|
|
return ((loss,) + output) if loss is not None else output
|
|
|
|
return TokenClassifierOutput(
|
|
loss=loss,
|
|
logits=logits,
|
|
hidden_states=transformer_outputs.hidden_states,
|
|
attentions=transformer_outputs.attentions,
|
|
)
|
|
|
|
|
|
@add_start_docstrings(
|
|
"""
|
|
The JAIS Model transformer with a span classification head on top for extractive question-answering tasks like
|
|
SQuAD (a linear layer on top of the hidden-states output to compute `span start logits` and `span end logits`).
|
|
""",
|
|
JAIS_START_DOCSTRING,
|
|
)
|
|
class JAISForQuestionAnswering(JAISPreTrainedModel):
|
|
_keys_to_ignore_on_load_unexpected = [r"h\.\d+\.attn\.bias", r"h\.\d+\.attn\.masked_bias"]
|
|
_keys_to_ignore_on_load_missing = [r"h\.\d+\.attn\.masked_bias", r"h\.\d+\.attn\.bias", r"lm_head.weight"]
|
|
|
|
def __init__(self, config):
|
|
super().__init__(config)
|
|
self.num_labels = config.num_labels
|
|
self.transformer = JAISModel(config)
|
|
self.qa_outputs = nn.Linear(config.hidden_size, 2)
|
|
self.output_logits_scale = config.mup_output_alpha * config.mup_width_scale
|
|
|
|
# Model parallel
|
|
self.model_parallel = False
|
|
self.device_map = None
|
|
self.gradient_checkpointing = False
|
|
|
|
# Initialize weights and apply final processing
|
|
self.post_init()
|
|
|
|
@add_start_docstrings_to_model_forward(JAIS_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
|
|
@add_code_sample_docstrings(
|
|
checkpoint=_CHECKPOINT_FOR_DOC,
|
|
output_type=QuestionAnsweringModelOutput,
|
|
config_class=_CONFIG_FOR_DOC,
|
|
real_checkpoint=_CHECKPOINT_FOR_DOC,
|
|
)
|
|
def forward(
|
|
self,
|
|
input_ids: Optional[torch.LongTensor] = None,
|
|
attention_mask: Optional[torch.FloatTensor] = None,
|
|
token_type_ids: Optional[torch.LongTensor] = None,
|
|
position_ids: Optional[torch.LongTensor] = None,
|
|
head_mask: Optional[torch.FloatTensor] = None,
|
|
inputs_embeds: Optional[torch.FloatTensor] = None,
|
|
start_positions: Optional[torch.LongTensor] = None,
|
|
end_positions: Optional[torch.LongTensor] = None,
|
|
output_attentions: Optional[bool] = None,
|
|
output_hidden_states: Optional[bool] = None,
|
|
return_dict: Optional[bool] = None,
|
|
) -> Union[Tuple, QuestionAnsweringModelOutput]:
|
|
r"""
|
|
start_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
|
|
Labels for position (index) of the start of the labelled span for computing the token classification loss.
|
|
Positions are clamped to the length of the sequence (`sequence_length`). Position outside of the sequence
|
|
are not taken into account for computing the loss.
|
|
end_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
|
|
Labels for position (index) of the end of the labelled span for computing the token classification loss.
|
|
Positions are clamped to the length of the sequence (`sequence_length`). Position outside of the sequence
|
|
are not taken into account for computing the loss.
|
|
"""
|
|
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
|
|
|
outputs = self.transformer(
|
|
input_ids,
|
|
attention_mask=attention_mask,
|
|
token_type_ids=token_type_ids,
|
|
position_ids=position_ids,
|
|
head_mask=head_mask,
|
|
inputs_embeds=inputs_embeds,
|
|
output_attentions=output_attentions,
|
|
output_hidden_states=output_hidden_states,
|
|
return_dict=return_dict,
|
|
)
|
|
|
|
sequence_output = outputs[0]
|
|
|
|
logits = self.qa_outputs(sequence_output)
|
|
logits *= torch.tensor(float(self.output_logits_scale), dtype=logits.dtype, device=logits.device)
|
|
start_logits, end_logits = logits.split(1, dim=-1)
|
|
start_logits = start_logits.squeeze(-1).contiguous()
|
|
end_logits = end_logits.squeeze(-1).contiguous()
|
|
|
|
total_loss = None
|
|
if start_positions is not None and end_positions is not None:
|
|
# If we are on multi-GPU, split add a dimension
|
|
if len(start_positions.size()) > 1:
|
|
start_positions = start_positions.squeeze(-1).to(start_logits.device)
|
|
if len(end_positions.size()) > 1:
|
|
end_positions = end_positions.squeeze(-1).to(end_logits.device)
|
|
# sometimes the start/end positions are outside our model inputs, we ignore these terms
|
|
ignored_index = start_logits.size(1)
|
|
start_positions = start_positions.clamp(0, ignored_index)
|
|
end_positions = end_positions.clamp(0, ignored_index)
|
|
|
|
loss_fct = CrossEntropyLoss(ignore_index=ignored_index)
|
|
start_loss = loss_fct(start_logits, start_positions)
|
|
end_loss = loss_fct(end_logits, end_positions)
|
|
total_loss = (start_loss + end_loss) / 2
|
|
|
|
if not return_dict:
|
|
output = (start_logits, end_logits) + outputs[2:]
|
|
return ((total_loss,) + output) if total_loss is not None else output
|
|
|
|
return QuestionAnsweringModelOutput(
|
|
loss=total_loss,
|
|
start_logits=start_logits,
|
|
end_logits=end_logits,
|
|
hidden_states=outputs.hidden_states,
|
|
attentions=outputs.attentions,
|
|
)
|