# coding=utf-8
# Copyright 2023 WisdomShell Inc. All Rights Reserved.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# This code is based on Bigcode's GPTBigCode model. It has been modified from
# its original forms to accommodate minor architectural differences compared to
# GPTBigCode model that trained the model.
# Copyright 2023 The Bigcode team and HuggingFace Inc. team.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""PyTorch CodeShell model."""
import os
import math
from typing import List, Optional, Tuple, Union, Callable
from threading import Thread
from queue import Queue
import torch
import torch.utils.checkpoint
from torch import nn
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from transformers import LogitsProcessorList, StoppingCriteriaList, StoppingCriteria, PreTrainedModel, PretrainedConfig
from transformers.generation.utils import GenerationConfig
from transformers.activations import ACT2FN
from transformers.modeling_outputs import (
BaseModelOutputWithPastAndCrossAttentions,
CausalLMOutputWithCrossAttentions,
)
from transformers.modeling_utils import PreTrainedModel
from transformers.utils import (
add_start_docstrings,
add_start_docstrings_to_model_forward,
)
from .configuration_codeshell import CodeShellConfig
# Fused kernels
# Use separate functions for each case because conditionals prevent kernel fusion.
# TODO: Could have better fused kernels depending on scaling, dropout and head mask.
# Is it doable without writing 32 functions?
@torch.jit.script
def upcast_masked_softmax(
x: torch.Tensor, mask: torch.Tensor, mask_value: torch.Tensor, scale: float, softmax_dtype: torch.dtype
):
input_dtype = x.dtype
x = x.to(softmax_dtype) * scale
x = torch.where(mask, x, mask_value)
x = torch.nn.functional.softmax(x, dim=-1).to(input_dtype)
return x
@torch.jit.script
def upcast_softmax(x: torch.Tensor, scale: float, softmax_dtype: torch.dtype):
input_dtype = x.dtype
x = x.to(softmax_dtype) * scale
x = torch.nn.functional.softmax(x, dim=-1).to(input_dtype)
return x
@torch.jit.script
def masked_softmax(x: torch.Tensor, mask: torch.Tensor, mask_value: torch.Tensor):
x = torch.where(mask, x, mask_value)
x = torch.nn.functional.softmax(x, dim=-1)
return x
class CodeShellRotaryEmbedding(torch.nn.Module):
def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None):
super().__init__()
self.dim = dim
self.max_position_embeddings = max_position_embeddings
self.base = base
inv_freq = 1.0 / (self.base ** (torch.arange(0, self.dim, 2).float().to(device) / self.dim))
self.register_buffer("inv_freq", inv_freq)
# Build here to make `torch.jit.trace` work.
self._set_cos_sin_cache(
seq_len=max_position_embeddings, device=self.inv_freq.device, dtype=torch.get_default_dtype()
)
def _set_cos_sin_cache(self, seq_len, device, dtype):
self.max_seq_len_cached = seq_len
t = torch.arange(self.max_seq_len_cached, device=device, dtype=self.inv_freq.dtype)
freqs = torch.einsum("i,j->ij", t, self.inv_freq)
# Different from paper, but it uses a different permutation in order to obtain the same calculation
emb = torch.cat((freqs, freqs), dim=-1)
self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
def forward(self, x, seq_len=None):
# x: [bs, num_attention_heads, seq_len, head_size]
if seq_len > self.max_seq_len_cached:
self._set_cos_sin_cache(seq_len=seq_len, device=x.device, dtype=x.dtype)
return (
self.cos_cached[:, :, :seq_len, ...].to(dtype=x.dtype),
self.sin_cached[:, :, :seq_len, ...].to(dtype=x.dtype),
)
class CodeShellLinearScalingRotaryEmbedding(CodeShellRotaryEmbedding):
"""CodeShellRotaryEmbedding extended with linear scaling. Credits to the Reddit user /u/kaiokendev"""
def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None, scaling_factor=1.0):
self.scaling_factor = scaling_factor
super().__init__(dim, max_position_embeddings, base, device)
def _set_cos_sin_cache(self, seq_len, device, dtype):
self.max_seq_len_cached = seq_len
t = torch.arange(self.max_seq_len_cached, device=device, dtype=self.inv_freq.dtype)
t = t / self.scaling_factor
freqs = torch.einsum("i,j->ij", t, self.inv_freq)
# Different from paper, but it uses a different permutation in order to obtain the same calculation
emb = torch.cat((freqs, freqs), dim=-1)
self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
class CodeShellDynamicNTKScalingRotaryEmbedding(CodeShellRotaryEmbedding):
"""ShellRotaryEmbedding extended with Dynamic NTK scaling. Credits to the Reddit users /u/bloc97 and /u/emozilla"""
def __init__(self, dim, max_position_embeddings=2048, base=10000, device=None, scaling_factor=1.0):
self.scaling_factor = scaling_factor
super().__init__(dim, max_position_embeddings, base, device)
def _set_cos_sin_cache(self, seq_len, device, dtype):
self.max_seq_len_cached = seq_len
if seq_len > self.max_position_embeddings:
base = self.base * (
(self.scaling_factor * seq_len / self.max_position_embeddings) - (self.scaling_factor - 1)
) ** (self.dim / (self.dim - 2))
inv_freq = 1.0 / (base ** (torch.arange(0, self.dim, 2).float().to(device) / self.dim))
self.register_buffer("inv_freq", inv_freq)
t = torch.arange(self.max_seq_len_cached, device=device, dtype=self.inv_freq.dtype)
freqs = torch.einsum("i,j->ij", t, self.inv_freq)
# Different from paper, but it uses a different permutation in order to obtain the same calculation
emb = torch.cat((freqs, freqs), dim=-1)
self.register_buffer("cos_cached", emb.cos()[None, None, :, :].to(dtype), persistent=False)
self.register_buffer("sin_cached", emb.sin()[None, None, :, :].to(dtype), persistent=False)
def rotate_half(x):
"""Rotates half the hidden dims of the input."""
x1 = x[..., : x.shape[-1] // 2]
x2 = x[..., x.shape[-1] // 2 :]
return torch.cat((-x2, x1), dim=-1)
def apply_rotary_pos_emb(q, k, cos, sin, position_ids):
# The first two dimensions of cos and sin are always 1, so we can `squeeze` them.
cos = cos.squeeze(1).squeeze(0) # [seq_len, dim]
sin = sin.squeeze(1).squeeze(0) # [seq_len, dim]
cos = cos[position_ids].unsqueeze(1) # [bs, 1, seq_len, dim]
sin = sin[position_ids].unsqueeze(1) # [bs, 1, seq_len, dim]
q_embed = (q * cos) + (rotate_half(q) * sin)
k_embed = (k * cos) + (rotate_half(k) * sin)
return q_embed, k_embed
def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor:
"""
This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch,
num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim)
"""
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)
class CodeShellAttention(nn.Module):
def __init__(self, config, layer_idx=None):
super().__init__()
self.mask_value = None
self.position_embedding_type = config.position_embedding_type
self.rope_scaling = config.rope_scaling
self.max_position_embeddings = config.max_position_embeddings
self.group_query_attention = config.group_query_attention
self.num_query_groups = config.num_query_groups
self.num_key_value_groups = config.num_attention_heads // config.num_query_groups
self.embed_dim = config.hidden_size
self.num_heads = config.num_attention_heads
self.head_dim = self.embed_dim // self.num_heads
self.kv_heads = config.num_query_groups if self.group_query_attention else self.num_heads
self.kv_dim = self.kv_heads * self.head_dim
self.split_size = self.embed_dim
if self.head_dim * self.num_heads != self.embed_dim:
raise ValueError(
f"`embed_dim` must be divisible by num_heads (got `embed_dim`: {self.embed_dim} and `num_heads`:"
f" {self.num_heads})."
)
self.layer_idx = layer_idx
self.c_attn = nn.Linear(self.embed_dim, self.embed_dim + 2 * self.kv_dim)
self.c_proj = nn.Linear(self.embed_dim, self.embed_dim)
self.attn_dropout = nn.Dropout(config.attn_pdrop)
self.resid_dropout = nn.Dropout(config.resid_pdrop)
if self.position_embedding_type == "rope":
self._init_rope()
def _init_rope(self):
if self.rope_scaling is None:
self.rotary_emb = CodeShellRotaryEmbedding(self.head_dim, max_position_embeddings=self.max_position_embeddings)
else:
scaling_type = self.rope_scaling["type"]
scaling_factor = self.rope_scaling["factor"]
if scaling_type == "linear":
self.rotary_emb = CodeShellLinearScalingRotaryEmbedding(
self.head_dim, max_position_embeddings=self.max_position_embeddings, scaling_factor=scaling_factor
)
elif scaling_type == "dynamic":
self.rotary_emb = CodeShellDynamicNTKScalingRotaryEmbedding(
self.head_dim, max_position_embeddings=self.max_position_embeddings, scaling_factor=scaling_factor
)
else:
raise ValueError(f"Unknown RoPE scaling type {scaling_type}")
def _get_mask_value(self, device, dtype):
# torch.where expects a tensor. We use a cache to avoid recreating it every time.
if self.mask_value is None or self.mask_value.dtype != dtype or self.mask_value.device != device:
self.mask_value = torch.full([], torch.finfo(dtype).min, dtype=dtype, device=device)
return self.mask_value
def forward(
self,
hidden_states: torch.Tensor,
layer_past: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
head_mask: Optional[torch.Tensor] = None,
use_cache: Optional[bool] = False,
output_attentions: Optional[bool] = False,
) -> Union[
Tuple[torch.Tensor, Optional[torch.Tensor]],
Tuple[torch.Tensor, Optional[torch.Tensor], Tuple[torch.Tensor, ...]],
]:
bsz, q_len, _ = hidden_states.size()
query_states, key_states, value_states = self.c_attn(hidden_states).split((self.embed_dim, self.kv_dim, self.kv_dim), dim=2)
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_query_groups, self.head_dim).transpose(1, 2)
value_states = value_states.view(bsz, q_len, self.num_query_groups, self.head_dim).transpose(1, 2)
kv_seq_len = key_states.shape[-2]
if layer_past is not None:
kv_seq_len += layer_past[0].shape[-2]
cos, sin = self.rotary_emb(value_states, seq_len=kv_seq_len)
query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin, position_ids)
if layer_past is not None:
# reuse k, v, self_attention
key_states = torch.cat([layer_past[0], key_states], dim=2)
value_states = torch.cat([layer_past[1], value_states], dim=2)
layer_past = (key_states, value_states) if use_cache else None
# repeat k/v heads if n_kv_heads < n_heads
key_states = repeat_kv(key_states, self.num_heads // self.kv_heads)
value_states = repeat_kv(value_states, self.num_heads // self.kv_heads)
attn_weights = torch.matmul(query_states, key_states.transpose(2, 3)) / math.sqrt(self.head_dim)
if attn_weights.size() != (bsz, self.num_heads, q_len, kv_seq_len):
raise ValueError(
f"Attention weights should be of size {(bsz, self.num_heads, q_len, kv_seq_len)}, but is"
f" {attn_weights.size()}"
)
if attention_mask is not None:
if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
raise ValueError(
f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
)
mask_value = self._get_mask_value(attn_weights.device, attn_weights.dtype)
# The fused kernel is very slow when the key length is not a multiple of 8, so we skip fusion.
attn_weights = torch.where(attention_mask, attn_weights, mask_value)
# upcast attention to fp32
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query_states.dtype)
attn_weights = self.attn_dropout(attn_weights)
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, self.embed_dim)
attn_output = self.c_proj(attn_output)
attn_output = self.resid_dropout(attn_output)
outputs = (attn_output, layer_past)
if output_attentions:
outputs += (attn_weights,)
return outputs # a, present, (attentions)
class CodeShellMLP(nn.Module):
def __init__(self, intermediate_size, config):
super().__init__()
embed_dim = config.hidden_size
self.c_fc = nn.Linear(embed_dim, intermediate_size)
self.c_proj = nn.Linear(intermediate_size, embed_dim)
self.act = ACT2FN[config.activation_function]
self.dropout = nn.Dropout(config.resid_pdrop)
# Copied from transformers.models.gpt2.modeling_gpt2.GPT2MLP.forward
def forward(self, hidden_states: Optional[Tuple[torch.Tensor]]) -> torch.Tensor:
hidden_states = self.c_fc(hidden_states)
hidden_states = self.act(hidden_states)
hidden_states = self.c_proj(hidden_states)
hidden_states = self.dropout(hidden_states)
return hidden_states
class CodeShellBlock(nn.Module):
def __init__(self, config, layer_idx=None):
super().__init__()
hidden_size = config.hidden_size
self.inner_dim = config.n_inner if config.n_inner is not None else 4 * hidden_size
self.ln_1 = nn.LayerNorm(hidden_size, eps=config.layer_norm_epsilon)
self.attn = CodeShellAttention(config, layer_idx=layer_idx)
self.ln_2 = nn.LayerNorm(hidden_size, eps=config.layer_norm_epsilon)
self.mlp = CodeShellMLP(self.inner_dim, config)
def forward(
self,
hidden_states: Optional[Tuple[torch.Tensor]],
layer_past: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
head_mask: Optional[torch.Tensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.Tensor] = None,
use_cache: Optional[bool] = False,
output_attentions: Optional[bool] = False,
) -> Union[
Tuple[torch.Tensor], Tuple[torch.Tensor, torch.Tensor], Tuple[torch.Tensor, torch.Tensor, torch.Tensor]
]:
residual = hidden_states
hidden_states = self.ln_1(hidden_states)
attn_outputs = self.attn(
hidden_states,
layer_past=layer_past,
attention_mask=attention_mask,
position_ids=position_ids,
head_mask=head_mask,
use_cache=use_cache,
output_attentions=output_attentions,
)
attn_output = attn_outputs[0] # output_attn: a, present, (attentions)
outputs = attn_outputs[1:]
# residual connection
hidden_states = attn_output + residual
residual = hidden_states
hidden_states = self.ln_2(hidden_states)
feed_forward_hidden_states = self.mlp(hidden_states)
# residual connection
hidden_states = residual + feed_forward_hidden_states
if use_cache:
outputs = (hidden_states,) + outputs
else:
outputs = (hidden_states,) + outputs[1:]
return outputs # hidden_states, present, (attentions, cross_attentions)
class CodeShellPreTrainedModel(PreTrainedModel):
"""
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
models.
"""
config_class = CodeShellConfig
base_model_prefix = "transformer"
supports_gradient_checkpointing = True
_no_split_modules = ["ShellBlock"]
_skip_keys_device_placement = "past_key_values"
def __init__(self, *inputs, **kwargs):
super().__init__(*inputs, **kwargs)
def _init_weights(self, module):
"""Initialize the weights."""
if isinstance(module, (CodeShellMLP, CodeShellAttention)):
# Reinitialize selected weights subject to the OpenAI GPT-2 Paper Scheme:
# > A modified initialization which accounts for the accumulation on the residual path with model depth. Scale
# > the weights of residual layers at initialization by a factor of 1/√N where N is the # of residual layers.
# > -- GPT-2 :: https://openai.com/blog/better-language-models/
#
# Reference (Megatron-LM): https://github.com/NVIDIA/Megatron-LM/blob/main/megatron/model/gpt_model.py
module.c_proj.weight.data.normal_(
mean=0.0, std=(self.config.initializer_range / math.sqrt(2 * self.config.n_layer))
)
module.c_proj._is_hf_initialized = True
elif isinstance(module, nn.Linear):
# Slightly different from the TF version which uses truncated_normal for initialization
# cf https://github.com/pytorch/pytorch/pull/5617
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.bias is not None:
module.bias.data.zero_()
elif isinstance(module, nn.Embedding):
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.padding_idx is not None:
module.weight.data[module.padding_idx].zero_()
elif isinstance(module, nn.LayerNorm):
module.bias.data.zero_()
module.weight.data.fill_(1.0)
# Copied from transformers.models.gpt2.modeling_gpt2.GPT2PreTrainedModel._set_gradient_checkpointing with GPT2->Shell
def _set_gradient_checkpointing(self, module, value=False):
if isinstance(module, CodeShellModel):
module.gradient_checkpointing = value
GPT_BIGCODE_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 ([`CodeShellConfig`]): 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.
"""
GPT_BIGCODE_INPUTS_DOCSTRING = r"""
Args:
input_ids (`torch.Tensor` of shape `(batch_size, input_ids_length)`):
`input_ids_length` = `sequence_length` if `past_key_values` is `None` else
`past_key_values[0][0].shape[-2]` (`sequence_length` of input past key value states). Indices of input
sequence tokens in the vocabulary.
If `past_key_values` is used, only `input_ids` that do not have their past calculated should be passed as
`input_ids`.
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
[`PreTrainedTokenizer.__call__`] for details.
[What are input IDs?](../glossary#input-ids)
past_key_values (`Tuple[torch.Tensor]` of length `config.n_layers`):
Contains precomputed hidden-states (key and values in the attention blocks) as computed by the model (see
`past_key_values` output below). Can be used to speed up sequential decoding. The `input_ids` which have
their past given to this model should not be passed as `input_ids` as they have already been computed.
attention_mask (`torch.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**.
If `past_key_values` is used, `attention_mask` needs to contain the masking strategy that was used for
`past_key_values`. In other words, the `attention_mask` always has to have the length:
`len(past_key_values) + len(input_ids)`
[What are attention masks?](../glossary#attention-mask)
token_type_ids (`torch.Tensor` of shape `(batch_size, input_ids_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,
1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
[What are token type IDs?](../glossary#token-type-ids)
position_ids (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
Indices of positions of each input sequence tokens in the position embeddings. Selected in the range `[0,
config.max_position_embeddings - 1]`.
[What are position IDs?](../glossary#position-ids)
head_mask (`torch.Tensor` of shape `(num_heads,)` or `(num_layers, num_heads)`, *optional*):
Mask to nullify selected heads of the self-attention modules. Mask values selected in `[0, 1]`:
- 1 indicates the head is **not masked**,
- 0 indicates the head is **masked**.
inputs_embeds (`torch.Tensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*):
Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This
is useful if you want more control over how to convert `input_ids` indices into associated vectors than the
model's internal embedding lookup matrix.
If `past_key_values` is used, optionally only the last `inputs_embeds` have to be input (see
`past_key_values`).
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see
`past_key_values`).
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
tensors for more detail.
output_hidden_states (`bool`, *optional*):
Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
more detail.
return_dict (`bool`, *optional*):
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
"""
@add_start_docstrings(
"The bare GPT_BIGCODE Model transformer outputting raw hidden-states without any specific head on top.",
GPT_BIGCODE_START_DOCSTRING,
)
class CodeShellModel(CodeShellPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.group_query_attention = config.group_query_attention
self.num_query_groups = config.num_query_groups
self.position_embedding_type = config.position_embedding_type
self.embed_dim = config.hidden_size
self.wte = nn.Embedding(config.vocab_size, self.embed_dim)
if self.position_embedding_type == "learned_absolute":
self.wpe = nn.Embedding(config.max_position_embeddings, self.embed_dim)
else:
pass
self.drop = nn.Dropout(config.embd_pdrop)
self.h = nn.ModuleList([CodeShellBlock(config, layer_idx=i) for i in range(config.num_hidden_layers)])
self.ln_f = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_epsilon)
max_positions = config.max_position_embeddings
self.register_buffer(
"bias", torch.tril(torch.ones((max_positions, max_positions), dtype=torch.bool)), persistent=False
)
self.gradient_checkpointing = False
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self):
return self.wte
def set_input_embeddings(self, new_embeddings):
self.wte = new_embeddings
@add_start_docstrings_to_model_forward(GPT_BIGCODE_INPUTS_DOCSTRING)
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
past_key_values: Optional[List[torch.Tensor]] = None,
attention_mask: Optional[torch.Tensor] = None,
token_type_ids: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
head_mask: Optional[torch.Tensor] = None,
inputs_embeds: Optional[torch.Tensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.Tensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[Tuple, BaseModelOutputWithPastAndCrossAttentions]:
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
use_cache = use_cache if use_cache is not None else self.config.use_cache
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if input_ids is not None and inputs_embeds is not None:
raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time")
elif input_ids is not None:
input_shape = input_ids.size()
input_ids = input_ids.reshape(-1, input_shape[-1])
batch_size = input_ids.shape[0]
elif inputs_embeds is not None:
input_shape = inputs_embeds.size()[:-1]
batch_size = inputs_embeds.shape[0]
else:
raise ValueError("You have to specify either input_ids or inputs_embeds")
if batch_size <= 0:
raise ValueError("batch_size has to be defined and > 0")
device = input_ids.device if input_ids is not None else inputs_embeds.device
if token_type_ids is not None:
token_type_ids = token_type_ids.reshape(-1, input_shape[-1])
if position_ids is not None:
position_ids = position_ids.reshape(-1, input_shape[-1])
if past_key_values is None:
past_length = 0
past_key_values = tuple([None] * len(self.h))
else:
past_length = past_key_values[0][0].size(-2)
if attention_mask is not None and len(attention_mask.shape) == 2 and position_ids is None:
# create position_ids on the fly for batch generation
position_ids = attention_mask.long().cumsum(-1) - 1
position_ids.masked_fill_(attention_mask == 0, 1)
if past_length > 0:
position_ids = position_ids[:, past_length : input_shape[-1] + past_length :]
elif position_ids is None:
position_ids = torch.arange(past_length, input_shape[-1] + past_length, dtype=torch.long, device=device)
position_ids = position_ids.unsqueeze(0).reshape(-1, input_shape[-1])
# Self-attention mask.
query_length = input_shape[-1]
key_length = past_length + query_length
self_attention_mask = self.bias[None, key_length - query_length : key_length, :key_length]
if attention_mask is not None:
self_attention_mask = self_attention_mask * attention_mask.reshape(batch_size, 1, -1).to(
dtype=torch.bool, device=self_attention_mask.device
)
# MQA models: (batch_size, query_length, n_heads, key_length)
# MHA models: (batch_size, n_heads, query_length, key_length)
attention_mask = self_attention_mask.unsqueeze(1)
encoder_attention_mask = None
# Prepare head mask if needed
# 1.0 in head_mask indicate we keep the head
# attention_probs has shape bsz x n_heads x N x N
# head_mask has shape n_layer x batch x n_heads x N x N
head_mask = self.get_head_mask(head_mask, self.config.n_layer)
if inputs_embeds is None:
inputs_embeds = self.wte(input_ids)
hidden_states = inputs_embeds
if self.position_embedding_type == "learned_absolute":
position_embeds = self.wpe(position_ids)
hidden_states = hidden_states + position_embeds
if token_type_ids is not None:
token_type_embeds = self.wte(token_type_ids)
hidden_states = hidden_states + token_type_embeds
hidden_states = self.drop(hidden_states)
output_shape = input_shape + (hidden_states.size(-1),)
presents = [] if use_cache else None
all_self_attentions = () if output_attentions else None
all_hidden_states = () if output_hidden_states else None
for i, (block, layer_past) in enumerate(zip(self.h, past_key_values)):
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if self.gradient_checkpointing and self.training:
def create_custom_forward(module):
def custom_forward(*inputs):
# None for past_key_value
return module(*inputs, use_cache, output_attentions)
return custom_forward
outputs = torch.utils.checkpoint.checkpoint(
create_custom_forward(block),
hidden_states,
None,
attention_mask,
position_ids,
head_mask[i],
encoder_hidden_states,
encoder_attention_mask,
)
else:
outputs = block(
hidden_states,
layer_past=layer_past,
attention_mask=attention_mask,
position_ids=position_ids,
head_mask=head_mask[i],
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
use_cache=use_cache,
output_attentions=output_attentions,
)
hidden_states = outputs[0]
if use_cache:
presents.append(outputs[1])
if output_attentions:
all_self_attentions = all_self_attentions + (outputs[2 if use_cache else 1],)
hidden_states = self.ln_f(hidden_states)
hidden_states = hidden_states.reshape(output_shape)
# Add last hidden state
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if not return_dict:
return tuple(
v
for v in [hidden_states, presents, all_hidden_states, all_self_attentions]
if v is not None
)
return BaseModelOutputWithPastAndCrossAttentions(
last_hidden_state=hidden_states,
past_key_values=presents,
hidden_states=all_hidden_states,
attentions=all_self_attentions,
)
class EndOfFunctionCriteria(StoppingCriteria):
"""Custom `StoppingCriteria` which checks if all generated functions in the batch are completed."""
def __init__(self, input_lengths, eof_strings, tokenizer):
self.input_lengths = input_lengths
self.eof_strings = eof_strings
self.tokenizer = tokenizer
def __call__(self, input_ids, scores, **kwargs):
"""Returns true if all generated sequences contain any of the end-of-function strings."""
decoded_generations = []
for _input_ids, input_length in zip(input_ids, self.input_lengths):
decoded_generations.append(self.tokenizer.decode(_input_ids[input_length:]))
done = []
for decoded_generation in decoded_generations:
done.append(
any(
[
stop_string in decoded_generation
for stop_string in self.eof_strings
]
)
)
return all(done)
class TextIterStreamer:
def __init__(self, tokenizer, skip_prompt=False, skip_special_tokens=False):
self.tokenizer = tokenizer
self.skip_prompt = skip_prompt
self.skip_special_tokens = skip_special_tokens
self.tokens = []
self.text_queue = Queue()
self.next_tokens_are_prompt = True
def put(self, value):
if self.skip_prompt and self.next_tokens_are_prompt:
self.next_tokens_are_prompt = False
else:
if len(value.shape) > 1:
value = value[0]
self.tokens.extend(value.tolist())
self.text_queue.put(
self.tokenizer.decode(self.tokens, skip_special_tokens=self.skip_special_tokens))
def end(self):
self.text_queue.put(None)
def __iter__(self):
return self
def __next__(self):
value = self.text_queue.get()
if value is None:
raise StopIteration()
else:
return value
@add_start_docstrings(
"""
The GPT_BIGCODE Model transformer with a language modeling head on top (linear layer with weights tied to the input
embeddings).
""",
GPT_BIGCODE_START_DOCSTRING,
)
class CodeShellForCausalLM(CodeShellPreTrainedModel):
_tied_weights_keys = ["lm_head.weight"]
def __init__(self, config):
super().__init__(config)
self.transformer = CodeShellModel(config)
self.lm_head = nn.Linear(config.n_embd, config.vocab_size, bias=False)
# Initialize weights and apply final processing
self.post_init()
def quantize(self, bits: int):
try:
import bitsandbytes
from .quantizer import quantize
except ImportError:
raise ImportError(f"Needs bitsandbytes to run quantize.")
return quantize(self, bits)
def get_output_embeddings(self):
return self.lm_head
def set_output_embeddings(self, new_embeddings):
self.lm_head = new_embeddings
def prepare_inputs_for_generation(self, input_ids, past_key_values=None, inputs_embeds=None, **kwargs):
token_type_ids = kwargs.get("token_type_ids", None)
# only last token for inputs_ids if past is defined in kwargs
if past_key_values:
input_ids = input_ids[:, -1].unsqueeze(-1)
if token_type_ids is not None:
token_type_ids = token_type_ids[:, -1].unsqueeze(-1)
attention_mask = kwargs.get("attention_mask", None)
position_ids = kwargs.get("position_ids", None)
if attention_mask is not None and position_ids is None:
# create position_ids on the fly for batch generation
position_ids = attention_mask.long().cumsum(-1) - 1
position_ids.masked_fill_(attention_mask == 0, 1)
if past_key_values:
position_ids = position_ids[:, -1].unsqueeze(-1)
else:
position_ids = None
# if `inputs_embeds` are passed, we only want to use them in the 1st generation step
if inputs_embeds is not None and past_key_values is None:
model_inputs = {"inputs_embeds": inputs_embeds}
else:
model_inputs = {"input_ids": input_ids}
model_inputs.update(
{
"past_key_values": past_key_values,
"use_cache": kwargs.get("use_cache"),
"position_ids": position_ids,
"attention_mask": attention_mask,
"token_type_ids": token_type_ids,
}
)
return model_inputs
@add_start_docstrings_to_model_forward(GPT_BIGCODE_INPUTS_DOCSTRING)
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
attention_mask: Optional[torch.Tensor] = None,
token_type_ids: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
head_mask: Optional[torch.Tensor] = None,
inputs_embeds: Optional[torch.Tensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.Tensor] = None,
labels: Optional[torch.Tensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[Tuple, CausalLMOutputWithCrossAttentions]:
r"""
labels (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for language modeling. Note that the labels **are shifted** inside the model, i.e. you can set
`labels = input_ids` Indices are selected in `[-100, 0, ..., config.vocab_size]` All labels set to `-100`
are ignored (masked), the loss is only computed for labels in `[0, ..., config.vocab_size]`
"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
transformer_outputs = self.transformer(
input_ids,
past_key_values=past_key_values,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
head_mask=head_mask,
inputs_embeds=inputs_embeds,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
hidden_states = transformer_outputs[0]
lm_logits = self.lm_head(hidden_states)
loss = None
if labels is not None:
# Shift so that tokens < n predict n
shift_logits = lm_logits[..., :-1, :].contiguous()
shift_labels = labels[..., 1:].contiguous().to(shift_logits.device)
# Flatten the tokens
loss_fct = CrossEntropyLoss()
loss = loss_fct(shift_logits.reshape(-1, shift_logits.size(-1)), shift_labels.reshape(-1))
if not return_dict:
output = (lm_logits,) + transformer_outputs[1:]
return ((loss,) + output) if loss is not None else output
return CausalLMOutputWithCrossAttentions(
loss=loss,
logits=lm_logits,
past_key_values=transformer_outputs.past_key_values,
hidden_states=transformer_outputs.hidden_states,
attentions=transformer_outputs.attentions,
)
@staticmethod
def _reorder_cache(past_key_values, beam_idx):
reordered_past = ()
for layer_past in past_key_values:
reordered_past += (
tuple(past_state.index_select(0, beam_idx.to(past_state.device)) for past_state in layer_past),
)
return reordered_past
def build_chat_input(self, query, history, tokenizer, max_new_tokens=None):
user_name = "## human:"
ai_name = "## assistant: "
stop = '|<end>|'
prompt = ''
for q, r in history:
prompt += f"{user_name}{q}{stop}"
prompt += f"{ai_name}{r}{stop}"
prompt += f"{user_name}{query}{stop}"
prompt += ai_name.rstrip()
max_new_tokens = max_new_tokens or self.generation_config.max_new_tokens
max_new_tokens = max_new_tokens or 128
max_input_tokens = self.config.n_positions - max_new_tokens
input_tokens = tokenizer.encode(prompt)
input_tokens = input_tokens[-max_input_tokens:] # truncate left
return torch.LongTensor([input_tokens]).to(self.device)
def chat(self, query, history, tokenizer, stream=False,
generation_config: Optional[GenerationConfig]=None):
generation_config = generation_config or self.generation_config
input_ids = self.build_chat_input(query, history, tokenizer, generation_config.max_new_tokens)
stopping_criteria = StoppingCriteriaList(
[EndOfFunctionCriteria([len(input_ids[0])], ['|<end>|', '|end|', '<|endoftext|>', '## human'], tokenizer)]
)
if stream:
streamer = TextIterStreamer(tokenizer, skip_prompt=True, skip_special_tokens=True)
Thread(target=self.generate, kwargs=dict(
inputs=input_ids, streamer=streamer,
stopping_criteria = stopping_criteria,
generation_config=generation_config,
)).start()
return streamer
else:
outputs = self.generate(input_ids, generation_config=generation_config, stopping_criteria = stopping_criteria)
response = tokenizer.decode(outputs[0][len(input_ids[0]):], skip_special_tokens=True)
return response
def generate_stream(self, prompt, tokenizer, generation_config=None, **kwargs):
generation_config = generation_config or self.generation_config
max_input_tokens = self.config.n_positions - self.generation_config.max_new_tokens
input_ids = tokenizer.encode(prompt)
input_ids = input_ids[-max_input_tokens:] # truncate left
stopping_criteria = StoppingCriteriaList(
[EndOfFunctionCriteria([len(input_ids[0])], ['|<end>|', '|end|', '<|endoftext|>', '## human'], tokenizer)]
)
streamer = TextIterStreamer(tokenizer, skip_prompt=True, skip_special_tokens=True)
Thread(target=self.generate, kwargs=dict(
inputs=input_ids, stopping_criteria=stopping_criteria, **kwargs
)).start()
return streamer
class CodeShell4bitForCausalLM(CodeShellForCausalLM):
def __init__(self, config):
CodeShellPreTrainedModel.__init__(self, config)
self.transformer = CodeShellModel(config)
self.lm_head = nn.Linear(config.n_embd, config.vocab_size, bias=False)
try:
import bitsandbytes
from .quantizer import quantize_offline
quantize_offline(self)
except ImportError:
raise ImportError(f"Needs bitsandbytes to run quantize.")
self.post_init()
@classmethod
def from_pretrained(
cls,
pretrained_model_name_or_path: Optional[Union[str, os.PathLike]],
*model_args,
config: Optional[Union[PretrainedConfig, str, os.PathLike]] = None,
cache_dir: Optional[Union[str, os.PathLike]] = None,
ignore_mismatched_sizes: bool = False,
force_download: bool = False,
local_files_only: bool = False,
token: Optional[Union[str, bool]] = None,
revision: str = "main",
use_safetensors: bool = None,
**kwargs,
):
if not isinstance(config, PretrainedConfig):
config_path = config if config is not None else pretrained_model_name_or_path
config, _ = cls.config_class.from_pretrained(
config_path,
cache_dir=cache_dir,
return_unused_kwargs=True,
force_download=force_download,
resume_download=False,
proxies=None,
local_files_only=local_files_only,
token=token,
revision=revision,
subfolder="",
_from_auto=False,
_from_pipeline=None,
**kwargs,
)
# Load config if we don't provide a configuration
from .quantizer import load_state_dict_for_qunantied_model
model = cls(config)
state_dict = torch.load(os.path.join(pretrained_model_name_or_path, 'pytorch_model.bin'), map_location="cpu")
model = load_state_dict_for_qunantied_model(model, state_dict)
model.eval()
# If it is a model with generation capabilities, attempt to load the generation config
if model.can_generate():
try:
model.generation_config = GenerationConfig.from_pretrained(
pretrained_model_name_or_path,
cache_dir=cache_dir,
force_download=force_download,
resume_download=False,
proxies=None,
local_files_only=local_files_only,
token=token,
revision=revision,
subfolder="",
_from_auto=False,
_from_pipeline=None,
**kwargs,
)
except (OSError, TypeError):
pass
device_map = kwargs.pop("device_map", None)
if device_map is not None:
model = model.to(torch.device(device_map))
return model