JosephusCheung commited on
Commit
64a9b89
1 Parent(s): c5a958a

Delete modeling_llama.py

Browse files
Files changed (1) hide show
  1. modeling_llama.py +0 -1013
modeling_llama.py DELETED
@@ -1,1013 +0,0 @@
1
- # coding=utf-8
2
- # Copyright 2022 EleutherAI and the HuggingFace Inc. team. All rights reserved.
3
- #
4
- # This code is based on EleutherAI's GPT-NeoX library and the GPT-NeoX
5
- # and OPT implementations in this library. It has been modified from its
6
- # original forms to accommodate minor architectural differences compared
7
- # to GPT-NeoX and OPT used by the Meta AI team that trained the model.
8
- #
9
- # Licensed under the Apache License, Version 2.0 (the "License");
10
- # you may not use this file except in compliance with the License.
11
- # You may obtain a copy of the License at
12
- #
13
- # http://www.apache.org/licenses/LICENSE-2.0
14
- #
15
- # Unless required by applicable law or agreed to in writing, software
16
- # distributed under the License is distributed on an "AS IS" BASIS,
17
- # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18
- # See the License for the specific language governing permissions and
19
- # limitations under the License.
20
- """ PyTorch LLaMA model."""
21
- import math
22
- from typing import List, Optional, Tuple, Union
23
-
24
- import torch
25
- import torch.nn.functional as F
26
- import torch.utils.checkpoint
27
- from torch import nn
28
- from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
29
-
30
- from ...activations import ACT2FN
31
- from ...modeling_outputs import BaseModelOutputWithPast, CausalLMOutputWithPast, SequenceClassifierOutputWithPast
32
- from ...modeling_utils import PreTrainedModel
33
- from ...utils import add_start_docstrings, add_start_docstrings_to_model_forward, logging, replace_return_docstrings
34
- from .configuration_llama import LlamaConfig
35
-
36
-
37
- logger = logging.get_logger(__name__)
38
-
39
- _CONFIG_FOR_DOC = "LlamaConfig"
40
-
41
-
42
- # Copied from transformers.models.bart.modeling_bart._make_causal_mask
43
- def _make_causal_mask(
44
- input_ids_shape: torch.Size, dtype: torch.dtype, device: torch.device, past_key_values_length: int = 0
45
- ):
46
- """
47
- Make causal mask used for bi-directional self-attention.
48
- """
49
- bsz, tgt_len = input_ids_shape
50
- mask = torch.full((tgt_len, tgt_len), torch.finfo(dtype).min, device=device)
51
- mask_cond = torch.arange(mask.size(-1), device=device)
52
- mask.masked_fill_(mask_cond < (mask_cond + 1).view(mask.size(-1), 1), 0)
53
- mask = mask.to(dtype)
54
-
55
- if past_key_values_length > 0:
56
- mask = torch.cat([torch.zeros(tgt_len, past_key_values_length, dtype=dtype, device=device), mask], dim=-1)
57
- return mask[None, None, :, :].expand(bsz, 1, tgt_len, tgt_len + past_key_values_length)
58
-
59
-
60
- # Copied from transformers.models.bart.modeling_bart._expand_mask
61
- def _expand_mask(mask: torch.Tensor, dtype: torch.dtype, tgt_len: Optional[int] = None):
62
- """
63
- Expands attention_mask from `[bsz, seq_len]` to `[bsz, 1, tgt_seq_len, src_seq_len]`.
64
- """
65
- bsz, src_len = mask.size()
66
- tgt_len = tgt_len if tgt_len is not None else src_len
67
-
68
- expanded_mask = mask[:, None, None, :].expand(bsz, 1, tgt_len, src_len).to(dtype)
69
-
70
- inverted_mask = 1.0 - expanded_mask
71
-
72
- return inverted_mask.masked_fill(inverted_mask.to(torch.bool), torch.finfo(dtype).min)
73
-
74
-
75
- class LlamaRMSNorm(nn.Module):
76
- def __init__(self, hidden_size, eps=1e-6):
77
- """
78
- LlamaRMSNorm is equivalent to T5LayerNorm
79
- """
80
- super().__init__()
81
- self.weight = nn.Parameter(torch.ones(hidden_size))
82
- self.variance_epsilon = eps
83
-
84
- def forward(self, hidden_states):
85
- input_dtype = hidden_states.dtype
86
- hidden_states = hidden_states.to(torch.float32)
87
- variance = hidden_states.pow(2).mean(-1, keepdim=True)
88
- hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
89
- return self.weight * hidden_states.to(input_dtype)
90
-
91
-
92
- class LlamaRotaryEmbedding(torch.nn.Module):
93
- def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None):
94
- super().__init__()
95
-
96
- self.dim = dim
97
- self.max_position_embeddings = max_position_embeddings
98
- self.base = base
99
- inv_freq = 1.0 / (self.base ** (torch.arange(0, self.dim, 2).float().to(device) / self.dim))
100
- self.register_buffer("inv_freq", inv_freq)
101
-
102
- # Build here to make `torch.jit.trace` work.
103
- self._set_cos_sin_cache(
104
- seq_len=max_position_embeddings, device=self.inv_freq.device, dtype=torch.get_default_dtype()
105
- )
106
-
107
- def _set_cos_sin_cache(self, seq_len, device, dtype):
108
- self.max_seq_len_cached = seq_len
109
- t = torch.arange(self.max_seq_len_cached, device=device, dtype=torch.float32)
110
-
111
- freqs = torch.einsum("i,j->ij", t, self.inv_freq)
112
- # Different from paper, but it uses a different permutation in order to obtain the same calculation
113
- emb = torch.cat((freqs, freqs), dim=-1)
114
- self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
115
- self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
116
-
117
- def forward(self, x, seq_len=None):
118
- # x: [bs, num_attention_heads, seq_len, head_size]
119
- if seq_len > self.max_seq_len_cached:
120
- self._set_cos_sin_cache(seq_len=seq_len, device=x.device, dtype=x.dtype)
121
-
122
- return (
123
- self.cos_cached[:, :, :seq_len, ...].to(dtype=x.dtype),
124
- self.sin_cached[:, :, :seq_len, ...].to(dtype=x.dtype),
125
- )
126
-
127
-
128
- class LlamaLinearScalingRotaryEmbedding(LlamaRotaryEmbedding):
129
- """LlamaRotaryEmbedding extended with linear scaling. Credits to the Reddit user /u/kaiokendev"""
130
-
131
- def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None, scaling_factor=1.0):
132
- self.scaling_factor = scaling_factor
133
- super().__init__(dim, max_position_embeddings, base, device)
134
-
135
- def _set_cos_sin_cache(self, seq_len, device, dtype):
136
- self.max_seq_len_cached = seq_len
137
- t = torch.arange(self.max_seq_len_cached, device=device, dtype=self.inv_freq.dtype)
138
- t = t / self.scaling_factor
139
-
140
- freqs = torch.einsum("i,j->ij", t, self.inv_freq)
141
- # Different from paper, but it uses a different permutation in order to obtain the same calculation
142
- emb = torch.cat((freqs, freqs), dim=-1)
143
- self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
144
- self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
145
-
146
-
147
- class LlamaDynamicNTKScalingRotaryEmbedding(LlamaRotaryEmbedding):
148
- """LlamaRotaryEmbedding extended with Dynamic NTK scaling. Credits to the Reddit users /u/bloc97 and /u/emozilla"""
149
-
150
- def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None, scaling_factor=1.0):
151
- self.scaling_factor = scaling_factor
152
- super().__init__(dim, max_position_embeddings, base, device)
153
-
154
- def _set_cos_sin_cache(self, seq_len, device, dtype):
155
- self.max_seq_len_cached = seq_len
156
-
157
- if seq_len > self.max_position_embeddings:
158
- base = self.base * (
159
- (self.scaling_factor * seq_len / self.max_position_embeddings) - (self.scaling_factor - 1)
160
- ) ** (self.dim / (self.dim - 2))
161
- inv_freq = 1.0 / (base ** (torch.arange(0, self.dim, 2).float().to(device) / self.dim))
162
- self.register_buffer("inv_freq", inv_freq)
163
-
164
- t = torch.arange(self.max_seq_len_cached, device=device, dtype=self.inv_freq.dtype)
165
-
166
- freqs = torch.einsum("i,j->ij", t, self.inv_freq)
167
- # Different from paper, but it uses a different permutation in order to obtain the same calculation
168
- emb = torch.cat((freqs, freqs), dim=-1)
169
- self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
170
- self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
171
-
172
-
173
- def rotate_half(x):
174
- """Rotates half the hidden dims of the input."""
175
- x1 = x[..., : x.shape[-1] // 2]
176
- x2 = x[..., x.shape[-1] // 2 :]
177
- return torch.cat((-x2, x1), dim=-1)
178
-
179
-
180
- def apply_rotary_pos_emb(q, k, cos, sin, position_ids):
181
- # The first two dimensions of cos and sin are always 1, so we can `squeeze` them.
182
- cos = cos.squeeze(1).squeeze(0) # [seq_len, dim]
183
- sin = sin.squeeze(1).squeeze(0) # [seq_len, dim]
184
- cos = cos[position_ids].unsqueeze(1) # [bs, 1, seq_len, dim]
185
- sin = sin[position_ids].unsqueeze(1) # [bs, 1, seq_len, dim]
186
- q_embed = (q * cos) + (rotate_half(q) * sin)
187
- k_embed = (k * cos) + (rotate_half(k) * sin)
188
- return q_embed, k_embed
189
-
190
-
191
- class LlamaMLP(nn.Module):
192
- def __init__(self, config):
193
- super().__init__()
194
- self.config = config
195
- self.hidden_size = config.hidden_size
196
- self.intermediate_size = config.intermediate_size
197
- self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
198
- self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
199
- self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=False)
200
- self.act_fn = ACT2FN[config.hidden_act]
201
-
202
- def forward(self, x):
203
- if self.config.pretraining_tp > 1:
204
- slice = self.intermediate_size // self.config.pretraining_tp
205
- gate_proj_slices = self.gate_proj.weight.split(slice, dim=0)
206
- up_proj_slices = self.up_proj.weight.split(slice, dim=0)
207
- down_proj_slices = self.down_proj.weight.split(slice, dim=1)
208
-
209
- gate_proj = torch.cat(
210
- [F.linear(x, gate_proj_slices[i]) for i in range(self.config.pretraining_tp)], dim=-1
211
- )
212
- up_proj = torch.cat([F.linear(x, up_proj_slices[i]) for i in range(self.config.pretraining_tp)], dim=-1)
213
-
214
- intermediate_states = (self.act_fn(gate_proj) * up_proj).split(slice, dim=2)
215
- down_proj = [
216
- F.linear(intermediate_states[i], down_proj_slices[i]) for i in range(self.config.pretraining_tp)
217
- ]
218
- down_proj = sum(down_proj)
219
- else:
220
- down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x))
221
-
222
- return down_proj
223
-
224
-
225
- def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor:
226
- """
227
- This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch,
228
- num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim)
229
- """
230
- batch, num_key_value_heads, slen, head_dim = hidden_states.shape
231
- if n_rep == 1:
232
- return hidden_states
233
- hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim)
234
- return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim)
235
-
236
-
237
- class LlamaAttention(nn.Module):
238
- """Multi-headed attention from 'Attention Is All You Need' paper"""
239
-
240
- def __init__(self, config: LlamaConfig):
241
- super().__init__()
242
- self.config = config
243
- self.hidden_size = config.hidden_size
244
- self.num_heads = config.num_attention_heads
245
- self.head_dim = self.hidden_size // self.num_heads
246
- self.num_key_value_heads = config.num_key_value_heads
247
- self.num_key_value_groups = self.num_heads // self.num_key_value_heads
248
- self.max_position_embeddings = config.max_position_embeddings
249
-
250
- if (self.head_dim * self.num_heads) != self.hidden_size:
251
- raise ValueError(
252
- f"hidden_size must be divisible by num_heads (got `hidden_size`: {self.hidden_size}"
253
- f" and `num_heads`: {self.num_heads})."
254
- )
255
- self.q_proj = nn.Linear(self.hidden_size, self.num_heads * self.head_dim, bias=False)
256
- self.k_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False)
257
- self.v_proj = nn.Linear(self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False)
258
- self.o_proj = nn.Linear(self.num_heads * self.head_dim, self.hidden_size, bias=False)
259
- self._init_rope()
260
-
261
- def _init_rope(self):
262
- if self.config.rope_scaling is None:
263
- self.rotary_emb = LlamaRotaryEmbedding(self.head_dim, max_position_embeddings=self.max_position_embeddings)
264
- else:
265
- scaling_type = self.config.rope_scaling["type"]
266
- scaling_factor = self.config.rope_scaling["factor"]
267
- if scaling_type == "linear":
268
- self.rotary_emb = LlamaLinearScalingRotaryEmbedding(
269
- self.head_dim, max_position_embeddings=self.max_position_embeddings, scaling_factor=scaling_factor
270
- )
271
- elif scaling_type == "dynamic":
272
- self.rotary_emb = LlamaDynamicNTKScalingRotaryEmbedding(
273
- self.head_dim, max_position_embeddings=self.max_position_embeddings, scaling_factor=scaling_factor
274
- )
275
- else:
276
- raise ValueError(f"Unknown RoPE scaling type {scaling_type}")
277
-
278
- def _shape(self, tensor: torch.Tensor, seq_len: int, bsz: int):
279
- return tensor.view(bsz, seq_len, self.num_heads, self.head_dim).transpose(1, 2).contiguous()
280
-
281
- def forward(
282
- self,
283
- hidden_states: torch.Tensor,
284
- attention_mask: Optional[torch.Tensor] = None,
285
- position_ids: Optional[torch.LongTensor] = None,
286
- past_key_value: Optional[Tuple[torch.Tensor]] = None,
287
- output_attentions: bool = False,
288
- use_cache: bool = False,
289
- ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
290
- bsz, q_len, _ = hidden_states.size()
291
-
292
- if self.config.pretraining_tp > 1:
293
- key_value_slicing = (self.num_key_value_heads * self.head_dim) // self.config.pretraining_tp
294
- query_slices = self.q_proj.weight.split(
295
- (self.num_heads * self.head_dim) // self.config.pretraining_tp, dim=0
296
- )
297
- key_slices = self.k_proj.weight.split(key_value_slicing, dim=0)
298
- value_slices = self.v_proj.weight.split(key_value_slicing, dim=0)
299
-
300
- query_states = [F.linear(hidden_states, query_slices[i]) for i in range(self.config.pretraining_tp)]
301
- query_states = torch.cat(query_states, dim=-1)
302
-
303
- key_states = [F.linear(hidden_states, key_slices[i]) for i in range(self.config.pretraining_tp)]
304
- key_states = torch.cat(key_states, dim=-1)
305
-
306
- value_states = [F.linear(hidden_states, value_slices[i]) for i in range(self.config.pretraining_tp)]
307
- value_states = torch.cat(value_states, dim=-1)
308
-
309
- else:
310
- query_states = self.q_proj(hidden_states)
311
- key_states = self.k_proj(hidden_states)
312
- value_states = self.v_proj(hidden_states)
313
-
314
- query_states = query_states.view(bsz, q_len, self.num_heads, self.head_dim).transpose(1, 2)
315
- key_states = key_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
316
- value_states = value_states.view(bsz, q_len, self.num_key_value_heads, self.head_dim).transpose(1, 2)
317
-
318
- kv_seq_len = key_states.shape[-2]
319
- if past_key_value is not None:
320
- kv_seq_len += past_key_value[0].shape[-2]
321
- cos, sin = self.rotary_emb(value_states, seq_len=kv_seq_len)
322
- query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin, position_ids)
323
-
324
- if past_key_value is not None:
325
- # reuse k, v, self_attention
326
- key_states = torch.cat([past_key_value[0], key_states], dim=2)
327
- value_states = torch.cat([past_key_value[1], value_states], dim=2)
328
-
329
- past_key_value = (key_states, value_states) if use_cache else None
330
-
331
- # repeat k/v heads if n_kv_heads < n_heads
332
- key_states = repeat_kv(key_states, self.num_key_value_groups)
333
- value_states = repeat_kv(value_states, self.num_key_value_groups)
334
-
335
- attn_weights = torch.matmul(query_states, key_states.transpose(2, 3)) / math.sqrt(self.head_dim)
336
-
337
- if attn_weights.size() != (bsz, self.num_heads, q_len, kv_seq_len):
338
- raise ValueError(
339
- f"Attention weights should be of size {(bsz, self.num_heads, q_len, kv_seq_len)}, but is"
340
- f" {attn_weights.size()}"
341
- )
342
-
343
- if attention_mask is not None:
344
- if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
345
- raise ValueError(
346
- f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
347
- )
348
- attn_weights = attn_weights + attention_mask
349
-
350
- # upcast attention to fp32
351
- attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query_states.dtype)
352
- attn_output = torch.matmul(attn_weights, value_states)
353
-
354
- if attn_output.size() != (bsz, self.num_heads, q_len, self.head_dim):
355
- raise ValueError(
356
- f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.head_dim)}, but is"
357
- f" {attn_output.size()}"
358
- )
359
-
360
- attn_output = attn_output.transpose(1, 2).contiguous()
361
- attn_output = attn_output.reshape(bsz, q_len, self.hidden_size)
362
-
363
- if self.config.pretraining_tp > 1:
364
- attn_output = attn_output.split(self.hidden_size // self.config.pretraining_tp, dim=2)
365
- o_proj_slices = self.o_proj.weight.split(self.hidden_size // self.config.pretraining_tp, dim=1)
366
- attn_output = sum([F.linear(attn_output[i], o_proj_slices[i]) for i in range(self.config.pretraining_tp)])
367
- else:
368
- attn_output = self.o_proj(attn_output)
369
-
370
- if not output_attentions:
371
- attn_weights = None
372
-
373
- return attn_output, attn_weights, past_key_value
374
-
375
-
376
- class LlamaDecoderLayer(nn.Module):
377
- def __init__(self, config: LlamaConfig):
378
- super().__init__()
379
- self.hidden_size = config.hidden_size
380
- self.self_attn = LlamaAttention(config=config)
381
- self.mlp = LlamaMLP(config)
382
- self.input_layernorm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
383
- self.post_attention_layernorm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
384
-
385
- def forward(
386
- self,
387
- hidden_states: torch.Tensor,
388
- attention_mask: Optional[torch.Tensor] = None,
389
- position_ids: Optional[torch.LongTensor] = None,
390
- past_key_value: Optional[Tuple[torch.Tensor]] = None,
391
- output_attentions: Optional[bool] = False,
392
- use_cache: Optional[bool] = False,
393
- ) -> Tuple[torch.FloatTensor, Optional[Tuple[torch.FloatTensor, torch.FloatTensor]]]:
394
- """
395
- Args:
396
- hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)`
397
- attention_mask (`torch.FloatTensor`, *optional*): attention mask of size
398
- `(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
399
- output_attentions (`bool`, *optional*):
400
- Whether or not to return the attentions tensors of all attention layers. See `attentions` under
401
- returned tensors for more detail.
402
- use_cache (`bool`, *optional*):
403
- If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
404
- (see `past_key_values`).
405
- past_key_value (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states
406
- """
407
-
408
- residual = hidden_states
409
-
410
- hidden_states = self.input_layernorm(hidden_states)
411
-
412
- # Self Attention
413
- hidden_states, self_attn_weights, present_key_value = self.self_attn(
414
- hidden_states=hidden_states,
415
- attention_mask=attention_mask,
416
- position_ids=position_ids,
417
- past_key_value=past_key_value,
418
- output_attentions=output_attentions,
419
- use_cache=use_cache,
420
- )
421
- hidden_states = residual + hidden_states
422
-
423
- # Fully Connected
424
- residual = hidden_states
425
- hidden_states = self.post_attention_layernorm(hidden_states)
426
- hidden_states = self.mlp(hidden_states)
427
- hidden_states = residual + hidden_states
428
-
429
- outputs = (hidden_states,)
430
-
431
- if output_attentions:
432
- outputs += (self_attn_weights,)
433
-
434
- if use_cache:
435
- outputs += (present_key_value,)
436
-
437
- return outputs
438
-
439
-
440
- LLAMA_START_DOCSTRING = r"""
441
- This model inherits from [`PreTrainedModel`]. Check the superclass documentation for the generic methods the
442
- library implements for all its model (such as downloading or saving, resizing the input embeddings, pruning heads
443
- etc.)
444
-
445
- This model is also a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass.
446
- Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage
447
- and behavior.
448
-
449
- Parameters:
450
- config ([`LlamaConfig`]):
451
- Model configuration class with all the parameters of the model. Initializing with a config file does not
452
- load the weights associated with the model, only the configuration. Check out the
453
- [`~PreTrainedModel.from_pretrained`] method to load the model weights.
454
- """
455
-
456
-
457
- @add_start_docstrings(
458
- "The bare LLaMA Model outputting raw hidden-states without any specific head on top.",
459
- LLAMA_START_DOCSTRING,
460
- )
461
- class LlamaPreTrainedModel(PreTrainedModel):
462
- config_class = LlamaConfig
463
- base_model_prefix = "model"
464
- supports_gradient_checkpointing = True
465
- _no_split_modules = ["LlamaDecoderLayer"]
466
- _skip_keys_device_placement = "past_key_values"
467
-
468
- def _init_weights(self, module):
469
- std = self.config.initializer_range
470
- if isinstance(module, nn.Linear):
471
- module.weight.data.normal_(mean=0.0, std=std)
472
- if module.bias is not None:
473
- module.bias.data.zero_()
474
- elif isinstance(module, nn.Embedding):
475
- module.weight.data.normal_(mean=0.0, std=std)
476
- if module.padding_idx is not None:
477
- module.weight.data[module.padding_idx].zero_()
478
-
479
- def _set_gradient_checkpointing(self, module, value=False):
480
- if isinstance(module, LlamaModel):
481
- module.gradient_checkpointing = value
482
-
483
-
484
- LLAMA_INPUTS_DOCSTRING = r"""
485
- Args:
486
- input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`):
487
- Indices of input sequence tokens in the vocabulary. Padding will be ignored by default should you provide
488
- it.
489
-
490
- Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
491
- [`PreTrainedTokenizer.__call__`] for details.
492
-
493
- [What are input IDs?](../glossary#input-ids)
494
- attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
495
- Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:
496
-
497
- - 1 for tokens that are **not masked**,
498
- - 0 for tokens that are **masked**.
499
-
500
- [What are attention masks?](../glossary#attention-mask)
501
-
502
- Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
503
- [`PreTrainedTokenizer.__call__`] for details.
504
-
505
- If `past_key_values` is used, optionally only the last `decoder_input_ids` have to be input (see
506
- `past_key_values`).
507
-
508
- If you want to change padding behavior, you should read [`modeling_opt._prepare_decoder_attention_mask`]
509
- and modify to your needs. See diagram 1 in [the paper](https://arxiv.org/abs/1910.13461) for more
510
- information on the default strategy.
511
-
512
- - 1 indicates the head is **not masked**,
513
- - 0 indicates the head is **masked**.
514
- position_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
515
- Indices of positions of each input sequence tokens in the position embeddings. Selected in the range `[0,
516
- config.n_positions - 1]`.
517
-
518
- [What are position IDs?](../glossary#position-ids)
519
- past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
520
- Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of shape
521
- `(batch_size, num_heads, sequence_length, embed_size_per_head)`) and 2 additional tensors of shape
522
- `(batch_size, num_heads, encoder_sequence_length, embed_size_per_head)`.
523
-
524
- Contains pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention
525
- blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.
526
-
527
- If `past_key_values` are used, the user can optionally input only the last `decoder_input_ids` (those that
528
- don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all
529
- `decoder_input_ids` of shape `(batch_size, sequence_length)`.
530
- inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*):
531
- Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This
532
- is useful if you want more control over how to convert `input_ids` indices into associated vectors than the
533
- model's internal embedding lookup matrix.
534
- use_cache (`bool`, *optional*):
535
- If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see
536
- `past_key_values`).
537
- output_attentions (`bool`, *optional*):
538
- Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
539
- tensors for more detail.
540
- output_hidden_states (`bool`, *optional*):
541
- Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
542
- more detail.
543
- return_dict (`bool`, *optional*):
544
- Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
545
- """
546
-
547
-
548
- @add_start_docstrings(
549
- "The bare LLaMA Model outputting raw hidden-states without any specific head on top.",
550
- LLAMA_START_DOCSTRING,
551
- )
552
- class LlamaModel(LlamaPreTrainedModel):
553
- """
554
- Transformer decoder consisting of *config.num_hidden_layers* layers. Each layer is a [`LlamaDecoderLayer`]
555
-
556
- Args:
557
- config: LlamaConfig
558
- """
559
-
560
- def __init__(self, config: LlamaConfig):
561
- super().__init__(config)
562
- self.padding_idx = config.pad_token_id
563
- self.vocab_size = config.vocab_size
564
-
565
- self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size, self.padding_idx)
566
- self.layers = nn.ModuleList([LlamaDecoderLayer(config) for _ in range(config.num_hidden_layers)])
567
- self.norm = LlamaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
568
-
569
- self.gradient_checkpointing = False
570
- # Initialize weights and apply final processing
571
- self.post_init()
572
-
573
- def get_input_embeddings(self):
574
- return self.embed_tokens
575
-
576
- def set_input_embeddings(self, value):
577
- self.embed_tokens = value
578
-
579
- # Copied from transformers.models.bart.modeling_bart.BartDecoder._prepare_decoder_attention_mask
580
- def _prepare_decoder_attention_mask(self, attention_mask, input_shape, inputs_embeds, past_key_values_length):
581
- # create causal mask
582
- # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
583
- combined_attention_mask = None
584
- if input_shape[-1] > 1:
585
- combined_attention_mask = _make_causal_mask(
586
- input_shape,
587
- inputs_embeds.dtype,
588
- device=inputs_embeds.device,
589
- past_key_values_length=past_key_values_length,
590
- )
591
-
592
- if attention_mask is not None:
593
- # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
594
- expanded_attn_mask = _expand_mask(attention_mask, inputs_embeds.dtype, tgt_len=input_shape[-1]).to(
595
- inputs_embeds.device
596
- )
597
- combined_attention_mask = (
598
- expanded_attn_mask if combined_attention_mask is None else expanded_attn_mask + combined_attention_mask
599
- )
600
-
601
- return combined_attention_mask
602
-
603
- @add_start_docstrings_to_model_forward(LLAMA_INPUTS_DOCSTRING)
604
- def forward(
605
- self,
606
- input_ids: torch.LongTensor = None,
607
- attention_mask: Optional[torch.Tensor] = None,
608
- position_ids: Optional[torch.LongTensor] = None,
609
- past_key_values: Optional[List[torch.FloatTensor]] = None,
610
- inputs_embeds: Optional[torch.FloatTensor] = None,
611
- use_cache: Optional[bool] = None,
612
- output_attentions: Optional[bool] = None,
613
- output_hidden_states: Optional[bool] = None,
614
- return_dict: Optional[bool] = None,
615
- ) -> Union[Tuple, BaseModelOutputWithPast]:
616
- output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
617
- output_hidden_states = (
618
- output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
619
- )
620
- use_cache = use_cache if use_cache is not None else self.config.use_cache
621
-
622
- return_dict = return_dict if return_dict is not None else self.config.use_return_dict
623
-
624
- # retrieve input_ids and inputs_embeds
625
- if input_ids is not None and inputs_embeds is not None:
626
- raise ValueError("You cannot specify both decoder_input_ids and decoder_inputs_embeds at the same time")
627
- elif input_ids is not None:
628
- batch_size, seq_length = input_ids.shape
629
- elif inputs_embeds is not None:
630
- batch_size, seq_length, _ = inputs_embeds.shape
631
- else:
632
- raise ValueError("You have to specify either decoder_input_ids or decoder_inputs_embeds")
633
-
634
- seq_length_with_past = seq_length
635
- past_key_values_length = 0
636
-
637
- if past_key_values is not None:
638
- past_key_values_length = past_key_values[0][0].shape[2]
639
- seq_length_with_past = seq_length_with_past + past_key_values_length
640
-
641
- if position_ids is None:
642
- device = input_ids.device if input_ids is not None else inputs_embeds.device
643
- position_ids = torch.arange(
644
- past_key_values_length, seq_length + past_key_values_length, dtype=torch.long, device=device
645
- )
646
- position_ids = position_ids.unsqueeze(0).view(-1, seq_length)
647
- else:
648
- position_ids = position_ids.view(-1, seq_length).long()
649
-
650
- if inputs_embeds is None:
651
- inputs_embeds = self.embed_tokens(input_ids)
652
- # embed positions
653
- if attention_mask is None:
654
- attention_mask = torch.ones(
655
- (batch_size, seq_length_with_past), dtype=torch.bool, device=inputs_embeds.device
656
- )
657
- attention_mask = self._prepare_decoder_attention_mask(
658
- attention_mask, (batch_size, seq_length), inputs_embeds, past_key_values_length
659
- )
660
-
661
- hidden_states = inputs_embeds
662
-
663
- if self.gradient_checkpointing and self.training:
664
- if use_cache:
665
- logger.warning_once(
666
- "`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
667
- )
668
- use_cache = False
669
-
670
- # decoder layers
671
- all_hidden_states = () if output_hidden_states else None
672
- all_self_attns = () if output_attentions else None
673
- next_decoder_cache = () if use_cache else None
674
-
675
- for idx, decoder_layer in enumerate(self.layers):
676
- if output_hidden_states:
677
- all_hidden_states += (hidden_states,)
678
-
679
- past_key_value = past_key_values[idx] if past_key_values is not None else None
680
-
681
- if self.gradient_checkpointing and self.training:
682
-
683
- def create_custom_forward(module):
684
- def custom_forward(*inputs):
685
- # None for past_key_value
686
- return module(*inputs, output_attentions, None)
687
-
688
- return custom_forward
689
-
690
- layer_outputs = torch.utils.checkpoint.checkpoint(
691
- create_custom_forward(decoder_layer),
692
- hidden_states,
693
- attention_mask,
694
- position_ids,
695
- None,
696
- )
697
- else:
698
- layer_outputs = decoder_layer(
699
- hidden_states,
700
- attention_mask=attention_mask,
701
- position_ids=position_ids,
702
- past_key_value=past_key_value,
703
- output_attentions=output_attentions,
704
- use_cache=use_cache,
705
- )
706
-
707
- hidden_states = layer_outputs[0]
708
-
709
- if use_cache:
710
- next_decoder_cache += (layer_outputs[2 if output_attentions else 1],)
711
-
712
- if output_attentions:
713
- all_self_attns += (layer_outputs[1],)
714
-
715
- hidden_states = self.norm(hidden_states)
716
-
717
- # add hidden states from the last decoder layer
718
- if output_hidden_states:
719
- all_hidden_states += (hidden_states,)
720
-
721
- next_cache = next_decoder_cache if use_cache else None
722
- if not return_dict:
723
- return tuple(v for v in [hidden_states, next_cache, all_hidden_states, all_self_attns] if v is not None)
724
- return BaseModelOutputWithPast(
725
- last_hidden_state=hidden_states,
726
- past_key_values=next_cache,
727
- hidden_states=all_hidden_states,
728
- attentions=all_self_attns,
729
- )
730
-
731
-
732
- class LlamaForCausalLM(LlamaPreTrainedModel):
733
- _tied_weights_keys = ["lm_head.weight"]
734
-
735
- def __init__(self, config):
736
- super().__init__(config)
737
- self.model = LlamaModel(config)
738
- self.vocab_size = config.vocab_size
739
- self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
740
-
741
- # Initialize weights and apply final processing
742
- self.post_init()
743
-
744
- def get_input_embeddings(self):
745
- return self.model.embed_tokens
746
-
747
- def set_input_embeddings(self, value):
748
- self.model.embed_tokens = value
749
-
750
- def get_output_embeddings(self):
751
- return self.lm_head
752
-
753
- def set_output_embeddings(self, new_embeddings):
754
- self.lm_head = new_embeddings
755
-
756
- def set_decoder(self, decoder):
757
- self.model = decoder
758
-
759
- def get_decoder(self):
760
- return self.model
761
-
762
- @add_start_docstrings_to_model_forward(LLAMA_INPUTS_DOCSTRING)
763
- @replace_return_docstrings(output_type=CausalLMOutputWithPast, config_class=_CONFIG_FOR_DOC)
764
- def forward(
765
- self,
766
- input_ids: torch.LongTensor = None,
767
- attention_mask: Optional[torch.Tensor] = None,
768
- position_ids: Optional[torch.LongTensor] = None,
769
- past_key_values: Optional[List[torch.FloatTensor]] = None,
770
- inputs_embeds: Optional[torch.FloatTensor] = None,
771
- labels: Optional[torch.LongTensor] = None,
772
- use_cache: Optional[bool] = None,
773
- output_attentions: Optional[bool] = None,
774
- output_hidden_states: Optional[bool] = None,
775
- return_dict: Optional[bool] = None,
776
- ) -> Union[Tuple, CausalLMOutputWithPast]:
777
- r"""
778
- Args:
779
- labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
780
- Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
781
- config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
782
- (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
783
-
784
- Returns:
785
-
786
- Example:
787
-
788
- ```python
789
- >>> from transformers import AutoTokenizer, LlamaForCausalLM
790
-
791
- >>> model = LlamaForCausalLM.from_pretrained(PATH_TO_CONVERTED_WEIGHTS)
792
- >>> tokenizer = AutoTokenizer.from_pretrained(PATH_TO_CONVERTED_TOKENIZER)
793
-
794
- >>> prompt = "Hey, are you conscious? Can you talk to me?"
795
- >>> inputs = tokenizer(prompt, return_tensors="pt")
796
-
797
- >>> # Generate
798
- >>> generate_ids = model.generate(inputs.input_ids, max_length=30)
799
- >>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0]
800
- "Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you."
801
- ```"""
802
-
803
- output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
804
- output_hidden_states = (
805
- output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
806
- )
807
- return_dict = return_dict if return_dict is not None else self.config.use_return_dict
808
-
809
- # decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn)
810
- outputs = self.model(
811
- input_ids=input_ids,
812
- attention_mask=attention_mask,
813
- position_ids=position_ids,
814
- past_key_values=past_key_values,
815
- inputs_embeds=inputs_embeds,
816
- use_cache=use_cache,
817
- output_attentions=output_attentions,
818
- output_hidden_states=output_hidden_states,
819
- return_dict=return_dict,
820
- )
821
-
822
- hidden_states = outputs[0]
823
- if self.config.pretraining_tp > 1:
824
- lm_head_slices = self.lm_head.weight.split(self.vocab_size // self.config.pretraining_tp, dim=0)
825
- logits = [F.linear(hidden_states, lm_head_slices[i]) for i in range(self.config.pretraining_tp)]
826
- logits = torch.cat(logits, dim=-1)
827
- else:
828
- logits = self.lm_head(hidden_states)
829
- logits = logits.float()
830
-
831
- loss = None
832
- if labels is not None:
833
- # Shift so that tokens < n predict n
834
- shift_logits = logits[..., :-1, :].contiguous()
835
- shift_labels = labels[..., 1:].contiguous()
836
- # Flatten the tokens
837
- loss_fct = CrossEntropyLoss()
838
- shift_logits = shift_logits.view(-1, self.config.vocab_size)
839
- shift_labels = shift_labels.view(-1)
840
- # Enable model parallelism
841
- shift_labels = shift_labels.to(shift_logits.device)
842
- loss = loss_fct(shift_logits, shift_labels)
843
-
844
- if not return_dict:
845
- output = (logits,) + outputs[1:]
846
- return (loss,) + output if loss is not None else output
847
-
848
- return CausalLMOutputWithPast(
849
- loss=loss,
850
- logits=logits,
851
- past_key_values=outputs.past_key_values,
852
- hidden_states=outputs.hidden_states,
853
- attentions=outputs.attentions,
854
- )
855
-
856
- def prepare_inputs_for_generation(
857
- self, input_ids, past_key_values=None, attention_mask=None, inputs_embeds=None, **kwargs
858
- ):
859
- if past_key_values:
860
- input_ids = input_ids[:, -1:]
861
-
862
- position_ids = kwargs.get("position_ids", None)
863
- if attention_mask is not None and position_ids is None:
864
- # create position_ids on the fly for batch generation
865
- position_ids = attention_mask.long().cumsum(-1) - 1
866
- position_ids.masked_fill_(attention_mask == 0, 1)
867
- if past_key_values:
868
- position_ids = position_ids[:, -1].unsqueeze(-1)
869
-
870
- # if `inputs_embeds` are passed, we only want to use them in the 1st generation step
871
- if inputs_embeds is not None and past_key_values is None:
872
- model_inputs = {"inputs_embeds": inputs_embeds}
873
- else:
874
- model_inputs = {"input_ids": input_ids}
875
-
876
- model_inputs.update(
877
- {
878
- "position_ids": position_ids,
879
- "past_key_values": past_key_values,
880
- "use_cache": kwargs.get("use_cache"),
881
- "attention_mask": attention_mask,
882
- }
883
- )
884
- return model_inputs
885
-
886
- @staticmethod
887
- def _reorder_cache(past_key_values, beam_idx):
888
- reordered_past = ()
889
- for layer_past in past_key_values:
890
- reordered_past += (
891
- tuple(past_state.index_select(0, beam_idx.to(past_state.device)) for past_state in layer_past),
892
- )
893
- return reordered_past
894
-
895
-
896
- @add_start_docstrings(
897
- """
898
- The LLaMa Model transformer with a sequence classification head on top (linear layer).
899
-
900
- [`LlamaForSequenceClassification`] uses the last token in order to do the classification, as other causal models
901
- (e.g. GPT-2) do.
902
-
903
- Since it does classification on the last token, it requires to know the position of the last token. If a
904
- `pad_token_id` is defined in the configuration, it finds the last token that is not a padding token in each row. If
905
- no `pad_token_id` is defined, it simply takes the last value in each row of the batch. Since it cannot guess the
906
- padding tokens when `inputs_embeds` are passed instead of `input_ids`, it does the same (take the last value in
907
- each row of the batch).
908
- """,
909
- LLAMA_START_DOCSTRING,
910
- )
911
- class LlamaForSequenceClassification(LlamaPreTrainedModel):
912
- def __init__(self, config):
913
- super().__init__(config)
914
- self.num_labels = config.num_labels
915
- self.model = LlamaModel(config)
916
- self.score = nn.Linear(config.hidden_size, self.num_labels, bias=False)
917
-
918
- # Initialize weights and apply final processing
919
- self.post_init()
920
-
921
- def get_input_embeddings(self):
922
- return self.model.embed_tokens
923
-
924
- def set_input_embeddings(self, value):
925
- self.model.embed_tokens = value
926
-
927
- @add_start_docstrings_to_model_forward(LLAMA_INPUTS_DOCSTRING)
928
- def forward(
929
- self,
930
- input_ids: torch.LongTensor = None,
931
- attention_mask: Optional[torch.Tensor] = None,
932
- position_ids: Optional[torch.LongTensor] = None,
933
- past_key_values: Optional[List[torch.FloatTensor]] = None,
934
- inputs_embeds: Optional[torch.FloatTensor] = None,
935
- labels: Optional[torch.LongTensor] = None,
936
- use_cache: Optional[bool] = None,
937
- output_attentions: Optional[bool] = None,
938
- output_hidden_states: Optional[bool] = None,
939
- return_dict: Optional[bool] = None,
940
- ) -> Union[Tuple, SequenceClassifierOutputWithPast]:
941
- r"""
942
- labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
943
- Labels for computing the sequence classification/regression loss. Indices should be in `[0, ...,
944
- config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
945
- `config.num_labels > 1` a classification loss is computed (Cross-Entropy).
946
- """
947
- return_dict = return_dict if return_dict is not None else self.config.use_return_dict
948
-
949
- transformer_outputs = self.model(
950
- input_ids,
951
- attention_mask=attention_mask,
952
- position_ids=position_ids,
953
- past_key_values=past_key_values,
954
- inputs_embeds=inputs_embeds,
955
- use_cache=use_cache,
956
- output_attentions=output_attentions,
957
- output_hidden_states=output_hidden_states,
958
- return_dict=return_dict,
959
- )
960
- hidden_states = transformer_outputs[0]
961
- logits = self.score(hidden_states)
962
-
963
- if input_ids is not None:
964
- batch_size = input_ids.shape[0]
965
- else:
966
- batch_size = inputs_embeds.shape[0]
967
-
968
- if self.config.pad_token_id is None and batch_size != 1:
969
- raise ValueError("Cannot handle batch sizes > 1 if no padding token is defined.")
970
- if self.config.pad_token_id is None:
971
- sequence_lengths = -1
972
- else:
973
- if input_ids is not None:
974
- sequence_lengths = (torch.ne(input_ids, self.config.pad_token_id).sum(-1) - 1).to(logits.device)
975
- else:
976
- sequence_lengths = -1
977
-
978
- pooled_logits = logits[torch.arange(batch_size, device=logits.device), sequence_lengths]
979
-
980
- loss = None
981
- if labels is not None:
982
- labels = labels.to(logits.device)
983
- if self.config.problem_type is None:
984
- if self.num_labels == 1:
985
- self.config.problem_type = "regression"
986
- elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
987
- self.config.problem_type = "single_label_classification"
988
- else:
989
- self.config.problem_type = "multi_label_classification"
990
-
991
- if self.config.problem_type == "regression":
992
- loss_fct = MSELoss()
993
- if self.num_labels == 1:
994
- loss = loss_fct(pooled_logits.squeeze(), labels.squeeze())
995
- else:
996
- loss = loss_fct(pooled_logits, labels)
997
- elif self.config.problem_type == "single_label_classification":
998
- loss_fct = CrossEntropyLoss()
999
- loss = loss_fct(pooled_logits.view(-1, self.num_labels), labels.view(-1))
1000
- elif self.config.problem_type == "multi_label_classification":
1001
- loss_fct = BCEWithLogitsLoss()
1002
- loss = loss_fct(pooled_logits, labels)
1003
- if not return_dict:
1004
- output = (pooled_logits,) + transformer_outputs[1:]
1005
- return ((loss,) + output) if loss is not None else output
1006
-
1007
- return SequenceClassifierOutputWithPast(
1008
- loss=loss,
1009
- logits=pooled_logits,
1010
- past_key_values=transformer_outputs.past_key_values,
1011
- hidden_states=transformer_outputs.hidden_states,
1012
- attentions=transformer_outputs.attentions,
1013
- )