| |
| |
| |
| |
| |
| |
| from typing import Callable, Optional, Union |
|
|
| import torch |
| from torch import nn |
|
|
| from ...activations import ACT2FN |
| from ...cache_utils import Cache, StaticCache |
| from ...modeling_attn_mask_utils import AttentionMaskConverter |
| from ...modeling_flash_attention_utils import FlashAttentionKwargs |
| from ...modeling_outputs import BaseModelOutputWithPast |
| from ...modeling_rope_utils import ROPE_INIT_FUNCTIONS |
| from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel |
| from ...processing_utils import Unpack |
| from ...utils import add_start_docstrings, add_start_docstrings_to_model_forward, logging |
| from .configuration_super import SuperConfig |
|
|
|
|
| logger = logging.get_logger(__name__) |
|
|
|
|
| class SuperRMSNorm(nn.Module): |
| def __init__(self, hidden_size, eps=1e-6): |
| """ |
| SuperRMSNorm is equivalent to T5LayerNorm |
| """ |
| super().__init__() |
| self.weight = nn.Parameter(torch.ones(hidden_size)) |
| self.variance_epsilon = eps |
|
|
| def forward(self, hidden_states): |
| input_dtype = hidden_states.dtype |
| hidden_states = hidden_states.to(torch.float32) |
| variance = hidden_states.pow(2).mean(-1, keepdim=True) |
| hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon) |
| return self.weight * hidden_states.to(input_dtype) |
|
|
| def extra_repr(self): |
| return f"{tuple(self.weight.shape)}, eps={self.variance_epsilon}" |
|
|
|
|
| class SuperRotaryEmbedding(nn.Module): |
| def __init__(self, config: SuperConfig, device=None): |
| super().__init__() |
| |
| if hasattr(config, "rope_scaling") and config.rope_scaling is not None: |
| self.rope_type = config.rope_scaling.get("rope_type", config.rope_scaling.get("type")) |
| else: |
| self.rope_type = "default" |
| self.max_seq_len_cached = config.max_position_embeddings |
| self.original_max_seq_len = config.max_position_embeddings |
|
|
| self.config = config |
| self.rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type] |
|
|
| inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device) |
| self.register_buffer("inv_freq", inv_freq, persistent=False) |
| self.original_inv_freq = self.inv_freq |
|
|
| def _dynamic_frequency_update(self, position_ids, device): |
| """ |
| dynamic RoPE layers should recompute `inv_freq` in the following situations: |
| 1 - growing beyond the cached sequence length (allow scaling) |
| 2 - the current sequence length is in the original scale (avoid losing precision with small sequences) |
| """ |
| seq_len = torch.max(position_ids) + 1 |
| if seq_len > self.max_seq_len_cached: |
| inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device, seq_len=seq_len) |
| self.register_buffer("inv_freq", inv_freq, persistent=False) |
| self.max_seq_len_cached = seq_len |
|
|
| if seq_len < self.original_max_seq_len and self.max_seq_len_cached > self.original_max_seq_len: |
| |
| |
| self.original_inv_freq = self.original_inv_freq.to(device) |
| self.register_buffer("inv_freq", self.original_inv_freq, persistent=False) |
| self.max_seq_len_cached = self.original_max_seq_len |
|
|
| @torch.no_grad() |
| def forward(self, x, position_ids): |
| if "dynamic" in self.rope_type: |
| self._dynamic_frequency_update(position_ids, device=x.device) |
|
|
| |
| inv_freq_expanded = self.inv_freq[None, :, None].float().expand(position_ids.shape[0], -1, 1) |
| position_ids_expanded = position_ids[:, None, :].float() |
| |
| device_type = x.device.type |
| device_type = device_type if isinstance(device_type, str) and device_type != "mps" else "cpu" |
| with torch.autocast(device_type=device_type, enabled=False): |
| freqs = (inv_freq_expanded.float() @ position_ids_expanded.float()).transpose(1, 2) |
| emb = torch.cat((freqs, freqs), dim=-1) |
| cos = emb.cos() |
| sin = emb.sin() |
|
|
| |
| cos = cos * self.attention_scaling |
| sin = sin * self.attention_scaling |
|
|
| return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype) |
|
|
|
|
| class SuperMLP(nn.Module): |
| def __init__(self, config): |
| super().__init__() |
| self.config = config |
| self.hidden_size = config.hidden_size |
| self.intermediate_size = config.intermediate_size |
| self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias) |
| self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias) |
| self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=config.mlp_bias) |
| self.act_fn = ACT2FN[config.hidden_act] |
|
|
| def forward(self, x): |
| down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x)) |
| return down_proj |
|
|
|
|
| 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=None, unsqueeze_dim=1): |
| """Applies Rotary Position Embedding to the query and key tensors. |
| |
| Args: |
| q (`torch.Tensor`): The query tensor. |
| k (`torch.Tensor`): The key tensor. |
| cos (`torch.Tensor`): The cosine part of the rotary embedding. |
| sin (`torch.Tensor`): The sine part of the rotary embedding. |
| position_ids (`torch.Tensor`, *optional*): |
| Deprecated and unused. |
| unsqueeze_dim (`int`, *optional*, defaults to 1): |
| The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and |
| sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note |
| that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and |
| k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes |
| cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have |
| the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2. |
| Returns: |
| `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding. |
| """ |
| cos = cos.unsqueeze(unsqueeze_dim) |
| sin = sin.unsqueeze(unsqueeze_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) |
|
|
|
|
| def eager_attention_forward( |
| module: nn.Module, |
| query: torch.Tensor, |
| key: torch.Tensor, |
| value: torch.Tensor, |
| attention_mask: Optional[torch.Tensor], |
| scaling: float, |
| dropout: float = 0.0, |
| **kwargs, |
| ): |
| key_states = repeat_kv(key, module.num_key_value_groups) |
| value_states = repeat_kv(value, module.num_key_value_groups) |
|
|
| attn_weights = torch.matmul(query, key_states.transpose(2, 3)) * scaling |
| 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.dtype) |
| attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training) |
| attn_output = torch.matmul(attn_weights, value_states) |
| attn_output = attn_output.transpose(1, 2).contiguous() |
|
|
| return attn_output, attn_weights |
|
|
|
|
| class SuperAttention(nn.Module): |
| """Multi-headed attention from 'Attention Is All You Need' paper""" |
|
|
| def __init__(self, config: SuperConfig, layer_idx: int): |
| super().__init__() |
| self.config = config |
| self.layer_idx = layer_idx |
| self.head_dim = getattr(config, "head_dim", config.hidden_size // config.num_attention_heads) |
| self.num_key_value_groups = config.num_attention_heads // config.num_key_value_heads |
| self.scaling = self.head_dim**-0.5 |
| self.attention_dropout = config.attention_dropout |
| self.is_causal = True |
|
|
| self.q_proj = nn.Linear( |
| config.hidden_size, config.num_attention_heads * self.head_dim, bias=config.attention_bias |
| ) |
| self.k_proj = nn.Linear( |
| config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias |
| ) |
| self.v_proj = nn.Linear( |
| config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias |
| ) |
| self.o_proj = nn.Linear( |
| config.num_attention_heads * self.head_dim, config.hidden_size, bias=config.attention_bias |
| ) |
|
|
| def forward( |
| self, |
| hidden_states: torch.Tensor, |
| position_embeddings: tuple[torch.Tensor, torch.Tensor], |
| attention_mask: Optional[torch.Tensor], |
| past_key_value: Optional[Cache] = None, |
| cache_position: Optional[torch.LongTensor] = None, |
| **kwargs: Unpack[FlashAttentionKwargs], |
| ) -> tuple[torch.Tensor, Optional[torch.Tensor], Optional[tuple[torch.Tensor]]]: |
| input_shape = hidden_states.shape[:-1] |
| hidden_shape = (*input_shape, -1, self.head_dim) |
|
|
| query_states = self.q_proj(hidden_states).view(hidden_shape).transpose(1, 2) |
| key_states = self.k_proj(hidden_states).view(hidden_shape).transpose(1, 2) |
| value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2) |
|
|
| 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) |
|
|
| attention_interface: Callable = eager_attention_forward |
| if self.config._attn_implementation != "eager": |
| if self.config._attn_implementation == "sdpa" and kwargs.get("output_attentions", False): |
| logger.warning_once( |
| "`torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to " |
| 'eager attention. This warning can be removed using the argument `attn_implementation="eager"` when loading the model.' |
| ) |
| else: |
| attention_interface = ALL_ATTENTION_FUNCTIONS[self.config._attn_implementation] |
|
|
| attn_output, attn_weights = attention_interface( |
| self, |
| query_states, |
| key_states, |
| value_states, |
| attention_mask, |
| dropout=0.0 if not self.training else self.attention_dropout, |
| scaling=self.scaling, |
| **kwargs, |
| ) |
|
|
| attn_output = attn_output.reshape(*input_shape, -1).contiguous() |
| attn_output = self.o_proj(attn_output) |
| return attn_output, attn_weights |
|
|
|
|
| class SuperDecoderLayer(nn.Module): |
| def __init__(self, config: SuperConfig, layer_idx: int): |
| super().__init__() |
| self.hidden_size = config.hidden_size |
|
|
| self.self_attn = SuperAttention(config=config, layer_idx=layer_idx) |
|
|
| self.mlp = SuperMLP(config) |
| self.input_layernorm = SuperRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
| self.post_attention_layernorm = SuperRMSNorm(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: Unpack[FlashAttentionKwargs], |
| ) -> tuple[torch.FloatTensor, Optional[tuple[torch.FloatTensor, torch.FloatTensor]]]: |
| residual = hidden_states |
|
|
| hidden_states = self.input_layernorm(hidden_states) |
|
|
| |
| hidden_states, self_attn_weights = 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,) |
|
|
| return outputs |
|
|
|
|
| SUPER_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 ([`SuperConfig`]): |
| 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 Super Model outputting raw hidden-states without any specific head on top.", |
| SUPER_START_DOCSTRING, |
| ) |
| class SuperPreTrainedModel(PreTrainedModel): |
| config_class = SuperConfig |
| base_model_prefix = "model" |
| supports_gradient_checkpointing = True |
| _no_split_modules = ["SuperDecoderLayer"] |
| _skip_keys_device_placement = ["past_key_values"] |
| _supports_flash_attn_2 = True |
| _supports_sdpa = True |
| _supports_flex_attn = True |
| _supports_cache_class = True |
| _supports_quantized_cache = True |
| _supports_static_cache = True |
| _supports_attention_backend = 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_() |
|
|
|
|
| SUPER_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, see our |
| [kv cache guide](https://huggingface.co/docs/transformers/en/kv_cache); |
| - 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 Super Model outputting raw hidden-states without any specific head on top.", |
| SUPER_START_DOCSTRING, |
| ) |
| class SuperModel(SuperPreTrainedModel): |
| """ |
| Transformer decoder consisting of *config.num_hidden_layers* layers. Each layer is a [`SuperDecoderLayer`] |
| |
| Args: |
| config: SuperConfig |
| """ |
|
|
| def __init__(self, config: SuperConfig): |
| 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( |
| [SuperDecoderLayer(config, layer_idx) for layer_idx in range(config.num_hidden_layers)] |
| ) |
| self.norm = SuperRMSNorm(config.hidden_size, eps=config.rms_norm_eps) |
| self.rotary_emb = SuperRotaryEmbedding(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(SUPER_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]: |
| out = super().forward( |
| input_ids, |
| attention_mask, |
| position_ids, |
| past_key_values, |
| inputs_embeds, |
| use_cache, |
| output_attentions, |
| output_hidden_states, |
| return_dict, |
| cache_position, |
| ) |
| out.logits *= 2**4 |
| return out |
|
|
| 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 (attention_mask == 0.0).any(): |
| 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 |
| sequence_length = input_tensor.shape[1] |
| if using_static_cache: |
| target_length = past_key_values.get_max_cache_shape() |
| else: |
| target_length = ( |
| attention_mask.shape[-1] |
| if isinstance(attention_mask, torch.Tensor) |
| else past_seen_tokens + sequence_length + 1 |
| ) |
|
|
| |
| causal_mask = self._prepare_4d_causal_attention_mask_with_cache_position( |
| attention_mask, |
| sequence_length=sequence_length, |
| target_length=target_length, |
| dtype=dtype, |
| device=device, |
| cache_position=cache_position, |
| batch_size=input_tensor.shape[0], |
| ) |
|
|
| if ( |
| self.config._attn_implementation == "sdpa" |
| and attention_mask is not None |
| and attention_mask.device.type in ["cuda", "xpu"] |
| and not output_attentions |
| ): |
| |
| |
| |
| min_dtype = torch.finfo(dtype).min |
| causal_mask = AttentionMaskConverter._unmask_unattended(causal_mask, min_dtype) |
|
|
| return causal_mask |
|
|
| @staticmethod |
| def _prepare_4d_causal_attention_mask_with_cache_position( |
| attention_mask: torch.Tensor, |
| sequence_length: int, |
| target_length: int, |
| dtype: torch.dtype, |
| device: torch.device, |
| cache_position: torch.Tensor, |
| batch_size: int, |
| **kwargs, |
| ): |
| """ |
| Creates a causal 4D mask of shape `(batch_size, 1, query_length, key_value_length)` from a 2D mask of shape |
| `(batch_size, key_value_length)`, or if the input `attention_mask` is already 4D, do nothing. |
| |
| Args: |
| attention_mask (`torch.Tensor`): |
| A 2D attention mask of shape `(batch_size, key_value_length)` or a 4D attention mask of shape |
| `(batch_size, 1, query_length, key_value_length)`. |
| sequence_length (`int`): |
| The sequence length being processed. |
| target_length (`int`): |
| The target length: when generating with static cache, the mask should be as long as the static cache, |
| to account for the 0 padding, the part of the cache that is not filled yet. |
| dtype (`torch.dtype`): |
| The dtype to use for the 4D attention mask. |
| device (`torch.device`): |
| The device to plcae the 4D attention mask on. |
| cache_position (`torch.Tensor`): |
| Indices depicting the position of the input sequence tokens in the sequence. |
| batch_size (`torch.Tensor`): |
| Batch size. |
| """ |
| if attention_mask is not None and attention_mask.dim() == 4: |
| |
| causal_mask = attention_mask |
| else: |
| min_dtype = torch.finfo(dtype).min |
| 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(batch_size, 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, :].to( |
| causal_mask.device |
| ) |
| padding_mask = padding_mask == 0 |
| causal_mask[:, :, :, :mask_length] = causal_mask[:, :, :, :mask_length].masked_fill( |
| padding_mask, min_dtype |
| ) |
|
|
| return causal_mask |
|
|