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import math |
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from typing import Optional, Tuple, Union, List, Callable, Dict, Any |
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import torch |
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import torch.nn.functional as F |
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import torch.utils.checkpoint |
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from torch import nn |
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from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss |
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|
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from transformers.activations import ACT2FN |
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from transformers.cache_utils import Cache, DynamicCache, StaticCache |
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from transformers.modeling_attn_mask_utils import AttentionMaskConverter |
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from transformers.modeling_flash_attention_utils import _flash_attention_forward |
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from transformers.modeling_outputs import ( |
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BaseModelOutputWithPast, |
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CausalLMOutputWithPast, |
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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_rope_utils import ROPE_INIT_FUNCTIONS |
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from transformers.modeling_utils import PreTrainedModel |
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from transformers.pytorch_utils import ALL_LAYERNORM_LAYERS |
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from transformers.utils import ( |
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add_start_docstrings, |
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add_start_docstrings_to_model_forward, |
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is_flash_attn_greater_or_equal_2_10, |
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logging, |
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replace_return_docstrings, |
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) |
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from transformers import LlamaConfig |
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from nltk.tokenize import PunktSentenceTokenizer |
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import re |
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logger = logging.get_logger(__name__) |
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_CONFIG_FOR_DOC = "LlamaConfig" |
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class LlamaRMSNorm(nn.Module): |
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def __init__(self, hidden_size, eps=1e-6): |
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""" |
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LlamaRMSNorm is equivalent to T5LayerNorm |
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""" |
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super().__init__() |
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self.weight = nn.Parameter(torch.ones(hidden_size)) |
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self.variance_epsilon = eps |
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def forward(self, hidden_states): |
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input_dtype = hidden_states.dtype |
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hidden_states = hidden_states.to(torch.float32) |
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variance = hidden_states.pow(2).mean(-1, keepdim=True) |
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hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon) |
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return self.weight * hidden_states.to(input_dtype) |
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ALL_LAYERNORM_LAYERS.append(LlamaRMSNorm) |
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class LlamaRotaryEmbedding(nn.Module): |
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def __init__( |
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self, |
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dim=None, |
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max_position_embeddings=2048, |
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base=10000, |
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device=None, |
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scaling_factor=1.0, |
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rope_type="default", |
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config: Optional[LlamaConfig] = None, |
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): |
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super().__init__() |
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self.rope_kwargs = {} |
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if config is None: |
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logger.warning_once( |
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"`LlamaRotaryEmbedding` can now be fully parameterized by passing the model config through the " |
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"`config` argument. All other arguments will be removed in v4.45" |
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) |
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self.rope_kwargs = { |
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"rope_type": rope_type, |
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"factor": scaling_factor, |
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"dim": dim, |
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"base": base, |
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"max_position_embeddings": max_position_embeddings, |
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} |
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self.rope_type = rope_type |
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self.max_seq_len_cached = max_position_embeddings |
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self.original_max_seq_len = max_position_embeddings |
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else: |
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if config.rope_scaling is not None: |
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self.rope_type = config.rope_scaling.get("rope_type", config.rope_scaling.get("type")) |
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else: |
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self.rope_type = "default" |
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self.max_seq_len_cached = config.max_position_embeddings |
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self.original_max_seq_len = config.max_position_embeddings |
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self.config = config |
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self.rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type] |
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inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device, **self.rope_kwargs) |
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self.register_buffer("inv_freq", inv_freq, persistent=False) |
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self.original_inv_freq = self.inv_freq |
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|
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def _dynamic_frequency_update(self, position_ids, device): |
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""" |
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dynamic RoPE layers should recompute `inv_freq` in the following situations: |
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1 - growing beyond the cached sequence length (allow scaling) |
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2 - the current sequence length is in the original scale (avoid losing precision with small sequences) |
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""" |
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seq_len = torch.max(position_ids) + 1 |
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if seq_len > self.max_seq_len_cached: |
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inv_freq, self.attention_scaling = self.rope_init_fn( |
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self.config, device, seq_len=seq_len, **self.rope_kwargs |
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) |
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self.register_buffer("inv_freq", inv_freq, persistent=False) |
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self.max_seq_len_cached = seq_len |
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if seq_len < self.original_max_seq_len and self.max_seq_len_cached > self.original_max_seq_len: |
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self.register_buffer("inv_freq", self.original_inv_freq, persistent=False) |
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self.max_seq_len_cached = self.original_max_seq_len |
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@torch.no_grad() |
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def forward(self, x, position_ids): |
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if "dynamic" in self.rope_type: |
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self._dynamic_frequency_update(position_ids, device=x.device) |
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inv_freq_expanded = self.inv_freq[None, :, None].float().expand(position_ids.shape[0], -1, 1) |
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position_ids_expanded = position_ids[:, None, :].float() |
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device_type = x.device.type |
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device_type = device_type if isinstance(device_type, str) and device_type != "mps" else "cpu" |
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with torch.autocast(device_type=device_type, enabled=False): |
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freqs = (inv_freq_expanded.float() @ position_ids_expanded.float()).transpose(1, 2) |
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emb = torch.cat((freqs, freqs), dim=-1) |
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cos = emb.cos() |
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sin = emb.sin() |
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cos = cos * self.attention_scaling |
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sin = sin * self.attention_scaling |
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return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype) |
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class LlamaLinearScalingRotaryEmbedding(LlamaRotaryEmbedding): |
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"""LlamaRotaryEmbedding extended with linear scaling. Credits to the Reddit user /u/kaiokendev""" |
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def __init__(self, *args, **kwargs): |
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logger.warning_once( |
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"`LlamaLinearScalingRotaryEmbedding` is deprecated an will be removed in v4.45. Please use " |
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"`LlamaRotaryEmbedding`, which now also does linear scaling (simply pass the model config to __init__)." |
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) |
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kwargs["rope_type"] = "linear" |
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super().__init__(*args, **kwargs) |
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class LlamaDynamicNTKScalingRotaryEmbedding(LlamaRotaryEmbedding): |
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"""LlamaRotaryEmbedding extended with Dynamic NTK scaling. Credits to the Reddit users /u/bloc97 and /u/emozilla""" |
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def __init__(self, *args, **kwargs): |
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logger.warning_once( |
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"`LlamaDynamicNTKScalingRotaryEmbedding` is deprecated an will be removed in v4.45. Please use " |
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"`LlamaRotaryEmbedding`, which now also does dynamic ntk scaling (simply pass the model config to " |
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"__init__)." |
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) |
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kwargs["rope_type"] = "dynamic" |
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super().__init__(*args, **kwargs) |
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def rotate_half(x): |
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"""Rotates half the hidden dims of the input.""" |
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x1 = x[..., : x.shape[-1] // 2] |
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x2 = x[..., x.shape[-1] // 2 :] |
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return torch.cat((-x2, x1), dim=-1) |
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def apply_rotary_pos_emb(q, k, cos, sin, position_ids=None, unsqueeze_dim=1): |
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"""Applies Rotary Position Embedding to the query and key tensors. |
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Args: |
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q (`torch.Tensor`): The query tensor. |
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k (`torch.Tensor`): The key tensor. |
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cos (`torch.Tensor`): The cosine part of the rotary embedding. |
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sin (`torch.Tensor`): The sine part of the rotary embedding. |
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position_ids (`torch.Tensor`, *optional*): |
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Deprecated and unused. |
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unsqueeze_dim (`int`, *optional*, defaults to 1): |
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The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and |
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sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note |
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that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and |
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k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes |
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cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have |
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the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2. |
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Returns: |
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`tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding. |
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""" |
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cos = cos.unsqueeze(unsqueeze_dim) |
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sin = sin.unsqueeze(unsqueeze_dim) |
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q_embed = (q * cos) + (rotate_half(q) * sin) |
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k_embed = (k * cos) + (rotate_half(k) * sin) |
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return q_embed, k_embed |
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class LlamaMLP(nn.Module): |
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def __init__(self, config): |
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super().__init__() |
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self.config = config |
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self.hidden_size = config.hidden_size |
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self.intermediate_size = config.intermediate_size |
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self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias) |
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self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias) |
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self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=config.mlp_bias) |
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self.act_fn = ACT2FN[config.hidden_act] |
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def forward(self, x): |
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if self.config.pretraining_tp > 1: |
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slice = self.intermediate_size // self.config.pretraining_tp |
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gate_proj_slices = self.gate_proj.weight.split(slice, dim=0) |
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up_proj_slices = self.up_proj.weight.split(slice, dim=0) |
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down_proj_slices = self.down_proj.weight.split(slice, dim=1) |
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|
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gate_proj = torch.cat( |
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[F.linear(x, gate_proj_slices[i]) for i in range(self.config.pretraining_tp)], dim=-1 |
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) |
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up_proj = torch.cat([F.linear(x, up_proj_slices[i]) for i in range(self.config.pretraining_tp)], dim=-1) |
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|
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intermediate_states = (self.act_fn(gate_proj) * up_proj).split(slice, dim=2) |
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down_proj = [ |
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F.linear(intermediate_states[i], down_proj_slices[i]) for i in range(self.config.pretraining_tp) |
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] |
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down_proj = sum(down_proj) |
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else: |
|
down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x)) |
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|
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return down_proj |
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|
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def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor: |
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""" |
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This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch, |
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num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim) |
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""" |
|
batch, num_key_value_heads, slen, head_dim = hidden_states.shape |
|
if n_rep == 1: |
|
return hidden_states |
|
hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim) |
|
return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim) |
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|
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class LlamaAttention(nn.Module): |
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"""Multi-headed attention from 'Attention Is All You Need' paper""" |
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|
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def __init__(self, config: LlamaConfig, layer_idx: Optional[int] = None): |
|
super().__init__() |
|
self.config = config |
|
self.layer_idx = layer_idx |
|
if layer_idx is None: |
|
logger.warning_once( |
|
f"Instantiating {self.__class__.__name__} without passing a `layer_idx` is not recommended and will " |
|
"lead to errors during the forward call if caching is used. Please make sure to provide a `layer_idx` " |
|
"when creating this class." |
|
) |
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|
|
self.attention_dropout = config.attention_dropout |
|
self.hidden_size = config.hidden_size |
|
self.num_heads = config.num_attention_heads |
|
self.head_dim = self.hidden_size // self.num_heads |
|
self.num_key_value_heads = config.num_key_value_heads |
|
self.num_key_value_groups = self.num_heads // self.num_key_value_heads |
|
self.max_position_embeddings = config.max_position_embeddings |
|
self.rope_theta = config.rope_theta |
|
self.is_causal = True |
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|
|
if (self.head_dim * self.num_heads) != self.hidden_size: |
|
raise ValueError( |
|
f"hidden_size must be divisible by num_heads (got `hidden_size`: {self.hidden_size}" |
|
f" and `num_heads`: {self.num_heads})." |
|
) |
|
|
|
self.q_proj = nn.Linear(self.hidden_size, self.num_heads * self.head_dim, bias=config.attention_bias) |
|
self.k_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=config.attention_bias) |
|
self.v_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=config.attention_bias) |
|
self.o_proj = nn.Linear(self.hidden_size, self.hidden_size, bias=config.attention_bias) |
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|
|
|
|
self.rotary_emb = LlamaRotaryEmbedding(config=self.config) |
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|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[Cache] = None, |
|
output_attentions: bool = False, |
|
use_cache: bool = False, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
position_embeddings: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, |
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**kwargs, |
|
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]: |
|
bsz, q_len, _ = hidden_states.size() |
|
|
|
if self.config.pretraining_tp > 1: |
|
key_value_slicing = (self.num_key_value_heads * self.head_dim) // self.config.pretraining_tp |
|
query_slices = self.q_proj.weight.split( |
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(self.num_heads * self.head_dim) // self.config.pretraining_tp, dim=0 |
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) |
|
key_slices = self.k_proj.weight.split(key_value_slicing, dim=0) |
|
value_slices = self.v_proj.weight.split(key_value_slicing, dim=0) |
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|
|
query_states = [F.linear(hidden_states, query_slices[i]) for i in range(self.config.pretraining_tp)] |
|
query_states = torch.cat(query_states, dim=-1) |
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|
|
key_states = [F.linear(hidden_states, key_slices[i]) for i in range(self.config.pretraining_tp)] |
|
key_states = torch.cat(key_states, dim=-1) |
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|
|
value_states = [F.linear(hidden_states, value_slices[i]) for i in range(self.config.pretraining_tp)] |
|
value_states = torch.cat(value_states, dim=-1) |
|
|
|
else: |
|
query_states = self.q_proj(hidden_states) |
|
key_states = self.k_proj(hidden_states) |
|
value_states = self.v_proj(hidden_states) |
|
|
|
query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2) |
|
key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
|
|
if position_embeddings is None: |
|
logger.warning_once( |
|
"The attention layers in this model are transitioning from computing the RoPE embeddings internally " |
|
"through `position_ids` (2D tensor with the indexes of the tokens), to using externally computed " |
|
"`position_embeddings` (Tuple of tensors, containing cos and sin). In v4.45 `position_ids` will be " |
|
"removed and `position_embeddings` will be mandatory." |
|
) |
|
cos, sin = self.rotary_emb(value_states, position_ids) |
|
else: |
|
cos, sin = position_embeddings |
|
|
|
query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin) |
|
|
|
if past_key_value is not None: |
|
|
|
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} |
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx, cache_kwargs) |
|
|
|
key_states = repeat_kv(key_states, self.num_key_value_groups) |
|
value_states = repeat_kv(value_states, self.num_key_value_groups) |
|
|
|
attn_weights = torch.matmul(query_states, key_states.transpose(2, 3)) / math.sqrt(self.head_dim) |
|
|
|
if attention_mask is not None: |
|
causal_mask = attention_mask[:, :, :, : key_states.shape[-2]] |
|
attn_weights = attn_weights + causal_mask |
|
|
|
|
|
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query_states.dtype) |
|
attn_weights = nn.functional.dropout(attn_weights, p=self.attention_dropout, training=self.training) |
|
attn_output = torch.matmul(attn_weights, value_states) |
|
|
|
if attn_output.size() != (bsz, self.num_heads, q_len, self.head_dim): |
|
raise ValueError( |
|
f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.head_dim)}, but is" |
|
f" {attn_output.size()}" |
|
) |
|
|
|
attn_output = attn_output.transpose(1, 2).contiguous() |
|
|
|
attn_output = attn_output.reshape(bsz, q_len, -1) |
|
|
|
if self.config.pretraining_tp > 1: |
|
attn_output = attn_output.split(self.hidden_size // self.config.pretraining_tp, dim=2) |
|
o_proj_slices = self.o_proj.weight.split(self.hidden_size // self.config.pretraining_tp, dim=1) |
|
attn_output = sum([F.linear(attn_output[i], o_proj_slices[i]) for i in range(self.config.pretraining_tp)]) |
|
else: |
|
attn_output = self.o_proj(attn_output) |
|
|
|
if not output_attentions: |
|
attn_weights = None |
|
|
|
return attn_output, attn_weights, past_key_value |
|
|
|
|
|
class LlamaFlashAttention2(LlamaAttention): |
|
""" |
|
Llama flash attention module. This module inherits from `LlamaAttention` as the weights of the module stays |
|
untouched. The only required change would be on the forward pass where it needs to correctly call the public API of |
|
flash attention and deal with padding tokens in case the input contains any of them. |
|
""" |
|
|
|
def __init__(self, *args, **kwargs): |
|
super().__init__(*args, **kwargs) |
|
|
|
|
|
|
|
|
|
self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal_2_10() |
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.LongTensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[Cache] = None, |
|
output_attentions: bool = False, |
|
use_cache: bool = False, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
position_embeddings: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, |
|
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]: |
|
if isinstance(past_key_value, StaticCache): |
|
raise ValueError( |
|
"`static` cache implementation is not compatible with `attn_implementation==flash_attention_2` " |
|
"make sure to use `sdpa` in the mean time, and open an issue at https://github.com/huggingface/transformers" |
|
) |
|
|
|
output_attentions = False |
|
|
|
bsz, q_len, _ = hidden_states.size() |
|
|
|
query_states = self.q_proj(hidden_states) |
|
key_states = self.k_proj(hidden_states) |
|
value_states = self.v_proj(hidden_states) |
|
|
|
|
|
|
|
|
|
query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2) |
|
key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
|
|
if position_embeddings is None: |
|
logger.warning_once( |
|
"The attention layers in this model are transitioning from computing the RoPE embeddings internally " |
|
"through `position_ids` (2D tensor with the indexes of the tokens), to using externally computed " |
|
"`position_embeddings` (Tuple of tensors, containing cos and sin). In v4.45 `position_ids` will be " |
|
"removed and `position_embeddings` will be mandatory." |
|
) |
|
cos, sin = self.rotary_emb(value_states, position_ids) |
|
else: |
|
cos, sin = position_embeddings |
|
|
|
query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin) |
|
|
|
if past_key_value is not None: |
|
|
|
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} |
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx, cache_kwargs) |
|
|
|
|
|
|
|
query_states = query_states.transpose(1, 2) |
|
key_states = key_states.transpose(1, 2) |
|
value_states = value_states.transpose(1, 2) |
|
|
|
dropout_rate = self.attention_dropout if self.training else 0.0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
input_dtype = query_states.dtype |
|
if input_dtype == torch.float32: |
|
if torch.is_autocast_enabled(): |
|
target_dtype = torch.get_autocast_gpu_dtype() |
|
|
|
elif hasattr(self.config, "_pre_quantization_dtype"): |
|
target_dtype = self.config._pre_quantization_dtype |
|
else: |
|
target_dtype = self.q_proj.weight.dtype |
|
|
|
logger.warning_once( |
|
f"The input hidden states seems to be silently casted in float32, this might be related to" |
|
f" the fact you have upcasted embedding or layer norm layers in float32. We will cast back the input in" |
|
f" {target_dtype}." |
|
) |
|
|
|
query_states = query_states.to(target_dtype) |
|
key_states = key_states.to(target_dtype) |
|
value_states = value_states.to(target_dtype) |
|
|
|
attn_output = _flash_attention_forward( |
|
query_states, |
|
key_states, |
|
value_states, |
|
attention_mask, |
|
q_len, |
|
dropout=dropout_rate, |
|
sliding_window=getattr(self, "sliding_window", None), |
|
use_top_left_mask=self._flash_attn_uses_top_left_mask, |
|
is_causal=self.is_causal, |
|
) |
|
|
|
attn_output = attn_output.reshape(bsz, q_len, -1).contiguous() |
|
attn_output = self.o_proj(attn_output) |
|
|
|
if not output_attentions: |
|
attn_weights = None |
|
|
|
return attn_output, attn_weights, past_key_value |
|
|
|
|
|
class LlamaSdpaAttention(LlamaAttention): |
|
""" |
|
Llama attention module using torch.nn.functional.scaled_dot_product_attention. This module inherits from |
|
`LlamaAttention` as the weights of the module stays untouched. The only changes are on the forward pass to adapt to |
|
SDPA API. |
|
""" |
|
|
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[Cache] = None, |
|
output_attentions: bool = False, |
|
use_cache: bool = False, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
position_embeddings: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, |
|
**kwargs, |
|
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]: |
|
if output_attentions: |
|
|
|
logger.warning_once( |
|
"LlamaModel is using LlamaSdpaAttention, but `torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to the manual attention implementation, " |
|
'but specifying the manual implementation will be required from Transformers version v5.0.0 onwards. This warning can be removed using the argument `attn_implementation="eager"` when loading the model.' |
|
) |
|
return super().forward( |
|
hidden_states=hidden_states, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_value, |
|
output_attentions=output_attentions, |
|
use_cache=use_cache, |
|
cache_position=cache_position, |
|
position_embeddings=position_embeddings, |
|
) |
|
|
|
bsz, q_len, _ = hidden_states.size() |
|
|
|
query_states = self.q_proj(hidden_states) |
|
key_states = self.k_proj(hidden_states) |
|
value_states = self.v_proj(hidden_states) |
|
|
|
query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2) |
|
key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2) |
|
|
|
if position_embeddings is None: |
|
logger.warning_once( |
|
"The attention layers in this model are transitioning from computing the RoPE embeddings internally " |
|
"through `position_ids` (2D tensor with the indexes of the tokens), to using externally computed " |
|
"`position_embeddings` (Tuple of tensors, containing cos and sin). In v4.45 `position_ids` will be " |
|
"removed and `position_embeddings` will be mandatory." |
|
) |
|
cos, sin = self.rotary_emb(value_states, position_ids) |
|
else: |
|
cos, sin = position_embeddings |
|
|
|
|
|
|
|
query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin) |
|
|
|
|
|
|
|
if past_key_value is not None: |
|
|
|
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} |
|
key_states, value_states = past_key_value.update(key_states, value_states, self.layer_idx, cache_kwargs) |
|
|
|
key_states = repeat_kv(key_states, self.num_key_value_groups) |
|
value_states = repeat_kv(value_states, self.num_key_value_groups) |
|
|
|
causal_mask = attention_mask |
|
if attention_mask is not None: |
|
causal_mask = causal_mask[:, :, :, : key_states.shape[-2]] |
|
|
|
|
|
|
|
if query_states.device.type == "cuda" and causal_mask is not None: |
|
query_states = query_states.contiguous() |
|
key_states = key_states.contiguous() |
|
value_states = value_states.contiguous() |
|
|
|
|
|
|
|
is_causal = True if causal_mask is None and q_len > 1 else False |
|
|
|
attn_output = torch.nn.functional.scaled_dot_product_attention( |
|
query_states, |
|
key_states, |
|
value_states, |
|
attn_mask=causal_mask, |
|
dropout_p=self.attention_dropout if self.training else 0.0, |
|
is_causal=is_causal, |
|
) |
|
|
|
attn_output = attn_output.transpose(1, 2).contiguous() |
|
attn_output = attn_output.view(bsz, q_len, -1) |
|
|
|
attn_output = self.o_proj(attn_output) |
|
|
|
return attn_output, None, past_key_value |
|
|
|
|
|
LLAMA_ATTENTION_CLASSES = { |
|
"eager": LlamaAttention, |
|
"flash_attention_2": LlamaFlashAttention2, |
|
"sdpa": LlamaSdpaAttention, |
|
} |
|
|
|
|
|
class LlamaDecoderLayer(nn.Module): |
|
def __init__(self, config: LlamaConfig, layer_idx: int): |
|
super().__init__() |
|
self.hidden_size = config.hidden_size |
|
|
|
self.self_attn = LLAMA_ATTENTION_CLASSES[config._attn_implementation](config=config, layer_idx=layer_idx) |
|
self.mlp = LlamaMLP(config) |
|
self.input_layernorm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
self.post_attention_layernorm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
|
|
def forward( |
|
self, |
|
hidden_states: torch.Tensor, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_value: Optional[Cache] = None, |
|
output_attentions: Optional[bool] = False, |
|
use_cache: Optional[bool] = False, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
position_embeddings: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, |
|
**kwargs, |
|
) -> Tuple[torch.FloatTensor, Optional[Tuple[torch.FloatTensor, torch.FloatTensor]]]: |
|
""" |
|
Args: |
|
hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)` |
|
attention_mask (`torch.FloatTensor`, *optional*): |
|
attention mask of size `(batch_size, sequence_length)` if flash attention is used or `(batch_size, 1, |
|
query_sequence_length, key_sequence_length)` if default attention is used. |
|
output_attentions (`bool`, *optional*): |
|
Whether or not to return the attentions tensors of all attention layers. See `attentions` under |
|
returned tensors for more detail. |
|
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`). |
|
past_key_value (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states |
|
cache_position (`torch.LongTensor` of shape `(sequence_length)`, *optional*): |
|
Indices depicting the position of the input sequence tokens in the sequence |
|
position_embeddings (`Tuple[torch.FloatTensor, torch.FloatTensor]`, *optional*): |
|
Tuple containing the cosine and sine positional embeddings of shape `(batch_size, seq_len, head_dim)`, |
|
with `head_dim` being the embedding dimension of each attention head. |
|
kwargs (`dict`, *optional*): |
|
Arbitrary kwargs to be ignored, used for FSDP and other methods that injects code |
|
into the model |
|
""" |
|
residual = hidden_states |
|
|
|
hidden_states = self.input_layernorm(hidden_states) |
|
|
|
|
|
|
|
hidden_states, self_attn_weights, present_key_value = self.self_attn( |
|
hidden_states=hidden_states, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_value, |
|
output_attentions=output_attentions, |
|
use_cache=use_cache, |
|
cache_position=cache_position, |
|
position_embeddings=position_embeddings, |
|
**kwargs, |
|
) |
|
hidden_states = residual + hidden_states |
|
|
|
|
|
residual = hidden_states |
|
hidden_states = self.post_attention_layernorm(hidden_states) |
|
hidden_states = self.mlp(hidden_states) |
|
hidden_states = residual + hidden_states |
|
|
|
outputs = (hidden_states,) |
|
|
|
if output_attentions: |
|
outputs += (self_attn_weights,) |
|
|
|
if use_cache: |
|
outputs += (present_key_value,) |
|
|
|
return outputs |
|
|
|
|
|
LLAMA_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 ([`LlamaConfig`]): |
|
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. |
|
""" |
|
|
|
|
|
@add_start_docstrings( |
|
"The bare LLaMA Model outputting raw hidden-states without any specific head on top.", |
|
LLAMA_START_DOCSTRING, |
|
) |
|
class LlamaPreTrainedModel(PreTrainedModel): |
|
config_class = LlamaConfig |
|
base_model_prefix = "model" |
|
supports_gradient_checkpointing = True |
|
_no_split_modules = ["LlamaDecoderLayer"] |
|
_skip_keys_device_placement = ["past_key_values"] |
|
_supports_flash_attn_2 = True |
|
_supports_sdpa = True |
|
_supports_cache_class = True |
|
_supports_quantized_cache = True |
|
_supports_static_cache = True |
|
|
|
def _init_weights(self, module): |
|
std = self.config.initializer_range |
|
if isinstance(module, nn.Linear): |
|
module.weight.data.normal_(mean=0.0, std=std) |
|
if module.bias is not None: |
|
module.bias.data.zero_() |
|
elif isinstance(module, nn.Embedding): |
|
module.weight.data.normal_(mean=0.0, std=std) |
|
if module.padding_idx is not None: |
|
module.weight.data[module.padding_idx].zero_() |
|
|
|
|
|
LLAMA_INPUTS_DOCSTRING = r""" |
|
Args: |
|
input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`): |
|
Indices of input sequence tokens in the vocabulary. Padding will be ignored by default should you provide |
|
it. |
|
|
|
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and |
|
[`PreTrainedTokenizer.__call__`] for details. |
|
|
|
[What are input IDs?](../glossary#input-ids) |
|
attention_mask (`torch.Tensor` 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) |
|
|
|
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and |
|
[`PreTrainedTokenizer.__call__`] for details. |
|
|
|
If `past_key_values` is used, optionally only the last `input_ids` have to be input (see |
|
`past_key_values`). |
|
|
|
If you want to change padding behavior, you should read [`modeling_opt._prepare_decoder_attention_mask`] |
|
and modify to your needs. See diagram 1 in [the paper](https://arxiv.org/abs/1910.13461) for more |
|
information on the default strategy. |
|
|
|
- 1 indicates the head is **not masked**, |
|
- 0 indicates the head is **masked**. |
|
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.n_positions - 1]`. |
|
|
|
[What are position IDs?](../glossary#position-ids) |
|
past_key_values (`Cache` or `tuple(tuple(torch.FloatTensor))`, *optional*): |
|
Pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention |
|
blocks) that can be used to speed up sequential decoding. This typically consists in the `past_key_values` |
|
returned by the model at a previous stage of decoding, when `use_cache=True` or `config.use_cache=True`. |
|
|
|
Two formats are allowed: |
|
- a [`~cache_utils.Cache`] instance; |
|
- Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of |
|
shape `(batch_size, num_heads, sequence_length, embed_size_per_head)`). This is also known as the legacy |
|
cache format. |
|
|
|
The model will output the same cache format that is fed as input. If no `past_key_values` are passed, the |
|
legacy cache format will be returned. |
|
|
|
If `past_key_values` are used, the user can optionally input only the last `input_ids` (those that don't |
|
have their past key value states given to this model) of shape `(batch_size, 1)` instead of all `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. |
|
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. |
|
cache_position (`torch.LongTensor` of shape `(sequence_length)`, *optional*): |
|
Indices depicting the position of the input sequence tokens in the sequence. Contrarily to `position_ids`, |
|
this tensor is not affected by padding. It is used to update the cache in the correct position and to infer |
|
the complete sequence length. |
|
""" |
|
|
|
|
|
@add_start_docstrings( |
|
"The bare LLaMA Model outputting raw hidden-states without any specific head on top.", |
|
LLAMA_START_DOCSTRING, |
|
) |
|
class LlamaModel(LlamaPreTrainedModel): |
|
""" |
|
Transformer decoder consisting of *config.num_hidden_layers* layers. Each layer is a [`LlamaDecoderLayer`] |
|
|
|
Args: |
|
config: LlamaConfig |
|
""" |
|
|
|
def __init__(self, config: LlamaConfig): |
|
super().__init__(config) |
|
self.padding_idx = config.pad_token_id |
|
self.vocab_size = config.vocab_size |
|
|
|
self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size, self.padding_idx) |
|
self.layers = nn.ModuleList( |
|
[LlamaDecoderLayer(config, layer_idx) for layer_idx in range(config.num_hidden_layers)] |
|
) |
|
self.norm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
|
self.rotary_emb = LlamaRotaryEmbedding(config=config) |
|
self.gradient_checkpointing = False |
|
|
|
|
|
self.post_init() |
|
|
|
def get_input_embeddings(self): |
|
return self.embed_tokens |
|
|
|
def set_input_embeddings(self, value): |
|
self.embed_tokens = value |
|
|
|
@add_start_docstrings_to_model_forward(LLAMA_INPUTS_DOCSTRING) |
|
def forward( |
|
self, |
|
input_ids: torch.LongTensor = None, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_values: Optional[Union[Cache, List[torch.FloatTensor]]] = None, |
|
inputs_embeds: 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, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
) -> Union[Tuple, BaseModelOutputWithPast]: |
|
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 None) ^ (inputs_embeds is not None): |
|
raise ValueError( |
|
"You cannot specify both input_ids and inputs_embeds at the same time, and must specify either one" |
|
) |
|
|
|
if self.gradient_checkpointing and self.training and use_cache: |
|
logger.warning_once( |
|
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`." |
|
) |
|
use_cache = False |
|
|
|
if inputs_embeds is None: |
|
inputs_embeds = self.embed_tokens(input_ids) |
|
|
|
return_legacy_cache = False |
|
if ( |
|
use_cache and not isinstance(past_key_values, Cache) and not self.training |
|
): |
|
return_legacy_cache = True |
|
past_key_values = DynamicCache.from_legacy_cache(past_key_values) |
|
logger.warning_once( |
|
"We detected that you are passing `past_key_values` as a tuple and this is deprecated and will be removed in v4.43. " |
|
"Please use an appropriate `Cache` class (https://huggingface.co/docs/transformers/v4.41.3/en/internal/generation_utils#transformers.Cache)" |
|
) |
|
|
|
if cache_position is None: |
|
past_seen_tokens = past_key_values.get_seq_length() if past_key_values is not None else 0 |
|
cache_position = torch.arange( |
|
past_seen_tokens, past_seen_tokens + inputs_embeds.shape[1], device=inputs_embeds.device |
|
) |
|
if position_ids is None: |
|
position_ids = cache_position.unsqueeze(0) |
|
|
|
causal_mask = self._update_causal_mask( |
|
attention_mask, inputs_embeds, cache_position, past_key_values, output_attentions |
|
) |
|
hidden_states = inputs_embeds |
|
|
|
|
|
position_embeddings = self.rotary_emb(hidden_states, position_ids) |
|
|
|
|
|
all_hidden_states = () if output_hidden_states else None |
|
all_self_attns = () if output_attentions else None |
|
next_decoder_cache = None |
|
|
|
for decoder_layer in self.layers: |
|
if output_hidden_states: |
|
all_hidden_states += (hidden_states,) |
|
|
|
if self.gradient_checkpointing and self.training: |
|
layer_outputs = self._gradient_checkpointing_func( |
|
decoder_layer.__call__, |
|
hidden_states, |
|
causal_mask, |
|
position_ids, |
|
past_key_values, |
|
output_attentions, |
|
use_cache, |
|
cache_position, |
|
position_embeddings, |
|
) |
|
else: |
|
layer_outputs = decoder_layer( |
|
hidden_states, |
|
attention_mask=causal_mask, |
|
position_ids=position_ids, |
|
past_key_value=past_key_values, |
|
output_attentions=output_attentions, |
|
use_cache=use_cache, |
|
cache_position=cache_position, |
|
position_embeddings=position_embeddings, |
|
) |
|
|
|
hidden_states = layer_outputs[0] |
|
|
|
if use_cache: |
|
next_decoder_cache = layer_outputs[2 if output_attentions else 1] |
|
|
|
if output_attentions: |
|
all_self_attns += (layer_outputs[1],) |
|
|
|
hidden_states = self.norm(hidden_states) |
|
|
|
|
|
if output_hidden_states: |
|
all_hidden_states += (hidden_states,) |
|
|
|
next_cache = next_decoder_cache if use_cache else None |
|
if return_legacy_cache: |
|
next_cache = next_cache.to_legacy_cache() |
|
|
|
if not return_dict: |
|
return tuple(v for v in [hidden_states, next_cache, all_hidden_states, all_self_attns] if v is not None) |
|
return BaseModelOutputWithPast( |
|
last_hidden_state=hidden_states, |
|
past_key_values=next_cache, |
|
hidden_states=all_hidden_states, |
|
attentions=all_self_attns, |
|
) |
|
|
|
def _update_causal_mask( |
|
self, |
|
attention_mask: torch.Tensor, |
|
input_tensor: torch.Tensor, |
|
cache_position: torch.Tensor, |
|
past_key_values: Cache, |
|
output_attentions: bool, |
|
): |
|
|
|
|
|
|
|
|
|
|
|
if self.config._attn_implementation == "flash_attention_2": |
|
if attention_mask is not None and 0.0 in attention_mask: |
|
return attention_mask |
|
return None |
|
|
|
|
|
|
|
|
|
past_seen_tokens = past_key_values.get_seq_length() if past_key_values is not None else 0 |
|
using_static_cache = isinstance(past_key_values, StaticCache) |
|
|
|
|
|
if self.config._attn_implementation == "sdpa" and not using_static_cache and not output_attentions: |
|
if AttentionMaskConverter._ignore_causal_mask_sdpa( |
|
attention_mask, |
|
inputs_embeds=input_tensor, |
|
past_key_values_length=past_seen_tokens, |
|
is_training=self.training, |
|
): |
|
return None |
|
|
|
dtype, device = input_tensor.dtype, input_tensor.device |
|
min_dtype = torch.finfo(dtype).min |
|
sequence_length = input_tensor.shape[1] |
|
if using_static_cache: |
|
target_length = past_key_values.get_max_length() |
|
else: |
|
target_length = ( |
|
attention_mask.shape[-1] |
|
if isinstance(attention_mask, torch.Tensor) |
|
else past_seen_tokens + sequence_length + 1 |
|
) |
|
|
|
if attention_mask is not None and attention_mask.dim() == 4: |
|
|
|
if attention_mask.max() != 0: |
|
raise ValueError("Custom 4D attention mask should be passed in inverted form with max==0`") |
|
causal_mask = attention_mask |
|
else: |
|
causal_mask = torch.full( |
|
(sequence_length, target_length), fill_value=min_dtype, dtype=dtype, device=device |
|
) |
|
if sequence_length != 1: |
|
causal_mask = torch.triu(causal_mask, diagonal=1) |
|
causal_mask *= torch.arange(target_length, device=device) > cache_position.reshape(-1, 1) |
|
causal_mask = causal_mask[None, None, :, :].expand(input_tensor.shape[0], 1, -1, -1) |
|
if attention_mask is not None: |
|
causal_mask = causal_mask.clone() |
|
mask_length = attention_mask.shape[-1] |
|
padding_mask = causal_mask[:, :, :, :mask_length] + attention_mask[:, None, None, :] |
|
padding_mask = padding_mask == 0 |
|
causal_mask[:, :, :, :mask_length] = causal_mask[:, :, :, :mask_length].masked_fill( |
|
padding_mask, min_dtype |
|
) |
|
if ( |
|
self.config._attn_implementation == "sdpa" |
|
and attention_mask is not None |
|
and attention_mask.device.type == "cuda" |
|
and not output_attentions |
|
): |
|
|
|
|
|
|
|
causal_mask = AttentionMaskConverter._unmask_unattended(causal_mask, min_dtype) |
|
|
|
return causal_mask |
|
|
|
|
|
class LlamaForCausalLM(LlamaPreTrainedModel): |
|
_tied_weights_keys = ["lm_head.weight"] |
|
|
|
def __init__(self, config): |
|
super().__init__(config) |
|
self.model = LlamaModel(config) |
|
self.vocab_size = config.vocab_size |
|
self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False) |
|
|
|
|
|
self.post_init() |
|
|
|
def get_input_embeddings(self): |
|
return self.model.embed_tokens |
|
|
|
def set_input_embeddings(self, value): |
|
self.model.embed_tokens = value |
|
|
|
def get_output_embeddings(self): |
|
return self.lm_head |
|
|
|
def set_output_embeddings(self, new_embeddings): |
|
self.lm_head = new_embeddings |
|
|
|
def set_decoder(self, decoder): |
|
self.model = decoder |
|
|
|
def get_decoder(self): |
|
return self.model |
|
|
|
@add_start_docstrings_to_model_forward(LLAMA_INPUTS_DOCSTRING) |
|
@replace_return_docstrings(output_type=CausalLMOutputWithPast, config_class=_CONFIG_FOR_DOC) |
|
def forward( |
|
self, |
|
input_ids: torch.LongTensor = None, |
|
attention_mask: Optional[torch.Tensor] = None, |
|
position_ids: Optional[torch.LongTensor] = None, |
|
past_key_values: Optional[Union[Cache, List[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, |
|
cache_position: Optional[torch.LongTensor] = None, |
|
) -> Union[Tuple, CausalLMOutputWithPast]: |
|
r""" |
|
Args: |
|
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*): |
|
Labels for computing the masked language modeling loss. Indices should either be in `[0, ..., |
|
config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored |
|
(masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`. |
|
|
|
Returns: |
|
|
|
Example: |
|
|
|
```python |
|
>>> from transformers import AutoTokenizer, LlamaForCausalLM |
|
|
|
>>> model = LlamaForCausalLM.from_pretrained("meta-llama/Llama-2-7b-hf") |
|
>>> tokenizer = AutoTokenizer.from_pretrained("meta-llama/Llama-2-7b-hf") |
|
|
|
>>> prompt = "Hey, are you conscious? Can you talk to me?" |
|
>>> inputs = tokenizer(prompt, return_tensors="pt") |
|
|
|
>>> # Generate |
|
>>> generate_ids = model.generate(inputs.input_ids, max_length=30) |
|
>>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0] |
|
"Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you." |
|
```""" |
|
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 |
|
|
|
|
|
outputs = self.model( |
|
input_ids=input_ids, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
past_key_values=past_key_values, |
|
inputs_embeds=inputs_embeds, |
|
use_cache=use_cache, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
return_dict=return_dict, |
|
cache_position=cache_position, |
|
) |
|
|
|
hidden_states = outputs[0] |
|
if self.config.pretraining_tp > 1: |
|
lm_head_slices = self.lm_head.weight.split(self.vocab_size // self.config.pretraining_tp, dim=0) |
|
logits = [F.linear(hidden_states, lm_head_slices[i]) for i in range(self.config.pretraining_tp)] |
|
logits = torch.cat(logits, dim=-1) |
|
else: |
|
logits = self.lm_head(hidden_states) |
|
logits = logits.float() |
|
|
|
loss = None |
|
if labels is not None: |
|
|
|
shift_logits = logits[..., :-1, :].contiguous() |
|
shift_labels = labels[..., 1:].contiguous() |
|
|
|
loss_fct = CrossEntropyLoss() |
|
shift_logits = shift_logits.view(-1, self.config.vocab_size) |
|
shift_labels = shift_labels.view(-1) |
|
|
|
shift_labels = shift_labels.to(shift_logits.device) |
|
loss = loss_fct(shift_logits, shift_labels) |
|
|
|
if not return_dict: |
|
output = (logits,) + outputs[1:] |
|
return (loss,) + output if loss is not None else output |
|
|
|
return CausalLMOutputWithPast( |
|
loss=loss, |
|
logits=logits, |
|
past_key_values=outputs.past_key_values, |
|
hidden_states=outputs.hidden_states, |
|
attentions=outputs.attentions, |
|
) |
|
|
|
def prepare_inputs_for_generation( |
|
self, |
|
input_ids, |
|
past_key_values=None, |
|
attention_mask=None, |
|
inputs_embeds=None, |
|
cache_position=None, |
|
position_ids=None, |
|
use_cache=True, |
|
**kwargs, |
|
): |
|
|
|
|
|
|
|
if past_key_values is not None: |
|
if inputs_embeds is not None: |
|
input_ids = input_ids[:, -cache_position.shape[0] :] |
|
elif input_ids.shape[1] != cache_position.shape[0]: |
|
input_ids = input_ids[:, cache_position] |
|
|
|
if attention_mask is not None and position_ids is None: |
|
|
|
position_ids = attention_mask.long().cumsum(-1) - 1 |
|
position_ids.masked_fill_(attention_mask == 0, 1) |
|
if past_key_values: |
|
position_ids = position_ids[:, -input_ids.shape[1] :] |
|
|
|
|
|
if inputs_embeds is not None and cache_position[0] == 0: |
|
model_inputs = {"inputs_embeds": inputs_embeds} |
|
else: |
|
model_inputs = {"input_ids": input_ids.contiguous()} |
|
|
|
model_inputs.update( |
|
{ |
|
"position_ids": position_ids, |
|
"cache_position": cache_position, |
|
"past_key_values": past_key_values, |
|
"use_cache": use_cache, |
|
"attention_mask": attention_mask, |
|
} |
|
) |
|
return model_inputs |
|
|
|
@torch.inference_mode() |
|
def chat(self, tokenizer, query: str, history: List[Dict] = None, role: str = "user", |
|
max_length: int = 131072, num_beams=1, do_sample=True, top_p=0.7, temperature=0.95, |
|
**kwargs): |
|
if history is None: |
|
history = [] |
|
gen_kwargs = {"max_length": max_length, "num_beams": num_beams, "do_sample": do_sample, "top_p": top_p, |
|
"temperature": temperature, **kwargs} |
|
inputs = tokenizer.build_chat_input(query, history=history, role=role) |
|
del inputs['token_type_ids'] |
|
|
|
inputs = inputs.to(self.device) |
|
eos_token_id = [tokenizer.eos_token_id, tokenizer.get_command("<|user|>"), |
|
tokenizer.get_command("<|observation|>")] |
|
outputs = self.generate(**inputs, **gen_kwargs, eos_token_id=eos_token_id) |
|
outputs = outputs.tolist()[0][len(inputs["input_ids"][0]):-1] |
|
response = tokenizer.decode(outputs).strip() |
|
history.append({"role": role, "content": query}) |
|
return response, history |
|
|
|
def query_longcite(self, context, query, tokenizer, max_input_length=128000, max_new_tokens=1024, temperature=0.95): |
|
|
|
def text_split_by_punctuation(original_text, return_dict=False): |
|
|
|
text = original_text |
|
custom_sent_tokenizer = PunktSentenceTokenizer() |
|
punctuations = r"([。;!?])" |
|
|
|
separated = custom_sent_tokenizer.tokenize(text) |
|
separated = sum([re.split(punctuations, s) for s in separated], []) |
|
|
|
for i in range(1, len(separated)): |
|
if re.match(punctuations, separated[i]): |
|
separated[i-1] += separated[i] |
|
separated[i] = '' |
|
|
|
separated = [s for s in separated if s != ""] |
|
if len(separated) == 1: |
|
separated = original_text.split('\n\n') |
|
separated = [s.strip() for s in separated if s.strip() != ""] |
|
if not return_dict: |
|
return separated |
|
else: |
|
pos = 0 |
|
res = [] |
|
for i, sent in enumerate(separated): |
|
st = original_text.find(sent, pos) |
|
assert st != -1, sent |
|
ed = st + len(sent) |
|
res.append( |
|
{ |
|
'c_idx': i, |
|
'content': sent, |
|
'start_idx': st, |
|
'end_idx': ed, |
|
} |
|
) |
|
pos = ed |
|
return res |
|
|
|
def get_prompt(context, question): |
|
sents = text_split_by_punctuation(context, return_dict=True) |
|
splited_context = "" |
|
for i, s in enumerate(sents): |
|
st, ed = s['start_idx'], s['end_idx'] |
|
assert s['content'] == context[st:ed], s |
|
ed = sents[i+1]['start_idx'] if i < len(sents)-1 else len(context) |
|
sents[i] = { |
|
'content': context[st:ed], |
|
'start': st, |
|
'end': ed, |
|
'c_idx': s['c_idx'], |
|
} |
|
splited_context += f"<C{i}>"+context[st:ed] |
|
prompt = '''Please answer the user's question based on the following document. When a sentence S in your response uses information from some chunks in the document (i.e., <C{s1}>-<C_{e1}>, <C{s2}>-<C{e2}>, ...), please append these chunk numbers to S in the format "<statement>{S}<cite>[{s1}-{e1}][{s2}-{e2}]...</cite></statement>". You must answer in the same language as the user's question.\n\n[Document Start]\n%s\n[Document End]\n\n%s''' % (splited_context, question) |
|
return prompt, sents, splited_context |
|
|
|
def get_citations(statement, sents): |
|
c_texts = re.findall(r'<cite>(.*?)</cite>', statement, re.DOTALL) |
|
spans = sum([re.findall(r"\[([0-9]+\-[0-9]+)\]", c_text, re.DOTALL) for c_text in c_texts], []) |
|
statement = re.sub(r'<cite>(.*?)</cite>', '', statement, flags=re.DOTALL) |
|
merged_citations = [] |
|
for i, s in enumerate(spans): |
|
try: |
|
st, ed = [int(x) for x in s.split('-')] |
|
if st > len(sents) - 1 or ed < st: |
|
continue |
|
st, ed = max(0, st), min(ed, len(sents)-1) |
|
assert st <= ed, str(c_texts) + '\t' + str(len(sents)) |
|
if len(merged_citations) > 0 and st == merged_citations[-1]['end_sentence_idx'] + 1: |
|
merged_citations[-1].update({ |
|
"end_sentence_idx": ed, |
|
'end_char_idx': sents[ed]['end'], |
|
'cite': ''.join([x['content'] for x in sents[merged_citations[-1]['start_sentence_idx']:ed+1]]), |
|
}) |
|
else: |
|
merged_citations.append({ |
|
"start_sentence_idx": st, |
|
"end_sentence_idx": ed, |
|
"start_char_idx": sents[st]['start'], |
|
'end_char_idx': sents[ed]['end'], |
|
'cite': ''.join([x['content'] for x in sents[st:ed+1]]), |
|
}) |
|
except: |
|
print(c_texts, len(sents), statement) |
|
raise |
|
return statement, merged_citations[:3] |
|
|
|
def postprocess(answer, sents, splited_context): |
|
res = [] |
|
pos = 0 |
|
new_answer = "" |
|
while True: |
|
st = answer.find("<statement>", pos) |
|
if st == -1: |
|
st = len(answer) |
|
ed = answer.find("</statement>", st) |
|
statement = answer[pos:st] |
|
if len(statement.strip()) > 5: |
|
res.append({ |
|
"statement": statement, |
|
"citation": [] |
|
}) |
|
new_answer += f"<statement>{statement}<cite></cite></statement>" |
|
else: |
|
res.append({ |
|
"statement": statement, |
|
"citation": None, |
|
}) |
|
new_answer += statement |
|
|
|
if ed == -1: |
|
break |
|
|
|
statement = answer[st+len("<statement>"):ed] |
|
if len(statement.strip()) > 0: |
|
statement, citations = get_citations(statement, sents) |
|
res.append({ |
|
"statement": statement, |
|
"citation": citations |
|
}) |
|
c_str = ''.join(['[{}-{}]'.format(c['start_sentence_idx'], c['end_sentence_idx']) for c in citations]) |
|
new_answer += f"<statement>{statement}<cite>{c_str}</cite></statement>" |
|
else: |
|
res.append({ |
|
"statement": statement, |
|
"citation": None, |
|
}) |
|
new_answer += statement |
|
pos = ed + len("</statement>") |
|
return { |
|
"answer": new_answer.strip(), |
|
"statements_with_citations": [x for x in res if x['citation'] is not None], |
|
"splited_context": splited_context.strip(), |
|
"all_statements": res, |
|
} |
|
|
|
def truncate_from_middle(prompt, max_input_length=None, tokenizer=None): |
|
if max_input_length is None: |
|
return prompt |
|
else: |
|
assert tokenizer is not None |
|
tokenized_prompt = tokenizer.encode(prompt, add_special_tokens=False) |
|
if len(tokenized_prompt) > max_input_length: |
|
half = int(max_input_length/2) |
|
prompt = tokenizer.decode(tokenized_prompt[:half], skip_special_tokens=True)+tokenizer.decode(tokenized_prompt[-half:], skip_special_tokens=True) |
|
return prompt |
|
|
|
prompt, sents, splited_context = get_prompt(context, query) |
|
prompt = truncate_from_middle(prompt, max_input_length, tokenizer) |
|
output, _ = self.chat(tokenizer, prompt, history=[], max_new_tokens=max_new_tokens, temperature=temperature) |
|
result = postprocess(output, sents, splited_context) |
|
return result |
|
|
|
|
|
|
|
|