import math import struct import inspect import time from .LMConfig import LMConfig from typing import Any, Optional, Tuple, List, Union import numpy as np import torch import torch.nn.functional as F from torch import nn from transformers import PreTrainedModel from transformers.modeling_outputs import CausalLMOutputWithPast from torch import nn, einsum from einops import rearrange, repeat def exists(val): return val is not None # RMSNorm 类定义了一个用于归一化输入张量的模块。 class RMSNorm(torch.nn.Module): def __init__(self, dim: int, eps: float = 1e-6): super().__init__() self.eps = eps self.weight = nn.Parameter(torch.ones(dim)) def _norm(self, x): return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps) def forward(self, x): return self.weight * self._norm(x.float()).type_as(x) # precompute_pos_cis 函数用于预计算位置编码。 def precompute_pos_cis(dim: int, end: int = int(32 * 1024), theta: float = 1e6): freqs = 1.0 / (theta ** (torch.arange(0, dim, 2)[: (dim // 2)].float() / dim)) t = torch.arange(end, device=freqs.device) # type: ignore freqs = torch.outer(t, freqs).float() # type: ignore pos_cis = torch.polar(torch.ones_like(freqs), freqs) # complex64 return pos_cis # apply_rotary_emb 函数用于应用旋转位置编码。 def apply_rotary_emb(xq, xk, pos_cis): def unite_shape(pos_cis, x): ndim = x.ndim assert 0 <= 1 < ndim assert pos_cis.shape == (x.shape[1], x.shape[-1]) shape = [d if i == 1 or i == ndim - 1 else 1 for i, d in enumerate(x.shape)] return pos_cis.view(*shape) xq_ = torch.view_as_complex(xq.float().reshape(*xq.shape[:-1], -1, 2)) xk_ = torch.view_as_complex(xk.float().reshape(*xk.shape[:-1], -1, 2)) pos_cis = unite_shape(pos_cis, xq_) xq_out = torch.view_as_real(xq_ * pos_cis).flatten(3) xk_out = torch.view_as_real(xk_ * pos_cis).flatten(3) return xq_out.type_as(xq), xk_out.type_as(xk) # repeat_kv 函数用于重复键值对。 def repeat_kv(x: torch.Tensor, n_rep: int) -> torch.Tensor: """torch.repeat_interleave(x, dim=2, repeats=n_rep)""" bs, slen, n_kv_heads, head_dim = x.shape if n_rep == 1: return x return ( x[:, :, :, None, :] .expand(bs, slen, n_kv_heads, n_rep, head_dim) .reshape(bs, slen, n_kv_heads * n_rep, head_dim) ) class Attention(nn.Module): def __init__(self, args: LMConfig): super().__init__() self.n_kv_heads = args.n_heads if args.n_kv_heads is None else args.n_kv_heads assert args.n_heads % self.n_kv_heads == 0 self.n_local_heads = args.n_heads self.n_local_kv_heads = self.n_kv_heads self.n_rep = self.n_local_heads // self.n_local_kv_heads self.head_dim = args.dim // args.n_heads self.wq = nn.Linear(args.dim, args.n_heads * self.head_dim, bias=False) self.wk = nn.Linear(args.dim, self.n_kv_heads * self.head_dim, bias=False) self.wv = nn.Linear(args.dim, self.n_kv_heads * self.head_dim, bias=False) self.wo = nn.Linear(args.n_heads * self.head_dim, args.dim, bias=False) self.attn_dropout = nn.Dropout(args.dropout) self.resid_dropout = nn.Dropout(args.dropout) self.dropout = args.dropout self.flash = hasattr(torch.nn.functional, 'scaled_dot_product_attention') and args.flash_attn # print("WARNING: using slow attention. Flash Attention requires PyTorch >= 2.0") mask = torch.full((1, 1, args.max_seq_len, args.max_seq_len), float("-inf")) mask = torch.triu(mask, diagonal=1) self.register_buffer("mask", mask, persistent=False) def forward(self, x: torch.Tensor, pos_cis: torch.Tensor, past_key_value: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, use_cache=False, db_value=None): bsz, seq_len, _ = x.shape #bsz: 批量大小, seq_len: 序列长度, _: 隐藏维度 xq, xk, xv = self.wq(x), self.wk(x), self.wv(x) #将输入张量x分别通过线性层wq, wk, wv进行变换，得到查询、键和值。 xq = xq.view(bsz, seq_len, self.n_local_heads, self.head_dim) #将变换后的张量xq重塑为形状为(bsz, seq_len, n_local_heads, head_dim)的形状。 xk = xk.view(bsz, seq_len, self.n_local_kv_heads, self.head_dim) #将变换后的张量xk重塑为形状为(bsz, seq_len, n_local_kv_heads, head_dim)的形状。 xv = xv.view(bsz, seq_len, self.n_local_kv_heads, self.head_dim) #将变换后的张量xv重塑为形状为(bsz, seq_len, n_local_kv_heads, head_dim)的形状。 # 应用旋转位置编码 xq, xk = apply_rotary_emb(xq, xk, pos_cis) # kv_cache实现 if past_key_value is not None: xk = torch.cat([past_key_value[0], xk], dim=1) xv = torch.cat([past_key_value[1], xv], dim=1) past_kv = (xk, xv) if use_cache else None # 重复键值对 xq, xk, xv = ( xq.transpose(1, 2), repeat_kv(xk, self.n_rep).transpose(1, 2), repeat_kv(xv, self.n_rep).transpose(1, 2) ) # 如果提供了db_value，根据头的数量调整它的形状并与xv合并 if db_value is not None: # 确保db_value的形状与xv兼容，假设db_value形状为[B, N, H, D] if db_value.ndim == 4: # [B, N, H, D] db_value = db_value.transpose(1, 2) # -> [B, H, N, D] # 检查是否需要调整D维度 if db_value.shape[-1] != xv.shape[-1]: # 如果db_value的维度与xv不同，可以添加一个投影层 # 或者在这里使用简单的调整方法 # 这里我们简单地通过均值池化或重复来调整维度 if db_value.shape[-1] > xv.shape[-1]: # 降维 factor = db_value.shape[-1] // xv.shape[-1] db_value = db_value.view(bsz, self.n_local_heads, seq_len, factor, xv.shape[-1]) db_value = db_value.mean(dim=3) else: # 升维 factor = xv.shape[-1] // db_value.shape[-1] db_value = db_value.unsqueeze(-1).repeat(1, 1, 1, 1, factor) db_value = db_value.view(bsz, self.n_local_heads, seq_len, xv.shape[-1]) # 将db_value与xv相加或融合 # 这里我们简单地将它们相加，但你也可以使用其他融合方法 xv = xv + db_value # 使用Flash Attention if self.flash and seq_len != 1: dropout_p = self.dropout if self.training else 0.0 output = F.scaled_dot_product_attention( xq, xk, xv, attn_mask=None, dropout_p=dropout_p, is_causal=True ) else: scores = (xq @ xk.transpose(-2, -1)) / math.sqrt(self.head_dim) scores += self.mask[:, :, :seq_len, :seq_len] scores = F.softmax(scores.float(), dim=-1).type_as(xq) scores = self.attn_dropout(scores) output = scores @ xv output = output.transpose(1, 2).reshape(bsz, seq_len, -1) output = self.resid_dropout(self.wo(output)) return output, past_kv class CrossAttention(nn.Module): def __init__( self, config ): super().__init__() self.config = config self.to_q = nn.Linear(768, 768, bias=False) self.to_k = nn.Linear(768, 768, bias=False) self.to_v = nn.Linear(768, 768, bias=False) def forward(self, x, db, context_mask=None, pos_emb=None): # db = db.permute(0, 2, 1) q = self.to_q(x) k = self.to_k(db) v = self.to_v(db) if pos_emb is not None: q = q + pos_emb k = k + pos_emb v = v + pos_emb attn_scores = torch.matmul(q, k.transpose(-2, -1)) / math.sqrt(k.size(-1)) if context_mask is not None: attn_scores = attn_scores.masked_fill(context_mask == 0, -1e10) attn_weights = F.softmax(attn_scores, dim=-1) context = torch.matmul(attn_weights, v) return context class FeedForward(nn.Module): def __init__(self, config: LMConfig): super().__init__() if config.hidden_dim is None: hidden_dim = 4 * config.dim hidden_dim = int(2 * hidden_dim / 3) config.hidden_dim = config.multiple_of * ((hidden_dim + config.multiple_of - 1) // config.multiple_of) self.w1 = nn.Linear(config.dim, config.hidden_dim, bias=False) self.w2 = nn.Linear(config.hidden_dim, config.dim, bias=False) self.w3 = nn.Linear(config.dim, config.hidden_dim, bias=False) self.dropout = nn.Dropout(config.dropout) def forward(self, x): return self.dropout(self.w2(F.silu(self.w1(x)) * self.w3(x))) class MoEGate(nn.Module): def __init__(self, config: LMConfig): super().__init__() self.config = config self.top_k = config.num_experts_per_tok self.n_routed_experts = config.n_routed_experts self.scoring_func = config.scoring_func self.alpha = config.aux_loss_alpha self.seq_aux = config.seq_aux self.norm_topk_prob = config.norm_topk_prob self.gating_dim = config.dim self.weight = nn.Parameter(torch.empty((self.n_routed_experts, self.gating_dim))) self.reset_parameters() def reset_parameters(self) -> None: import torch.nn.init as init init.kaiming_uniform_(self.weight, a=math.sqrt(5)) def forward(self, hidden_states): bsz, seq_len, h = hidden_states.shape hidden_states = hidden_states.view(-1, h) logits = F.linear(hidden_states, self.weight, None) if self.scoring_func == 'softmax': scores = logits.softmax(dim=-1) else: raise NotImplementedError(f'insupportable scoring function for MoE gating: {self.scoring_func}') topk_weight, topk_idx = torch.topk(scores, k=self.top_k, dim=-1, sorted=False) if self.top_k > 1 and self.norm_topk_prob: denominator = topk_weight.sum(dim=-1, keepdim=True) + 1e-20 topk_weight = topk_weight / denominator if self.training and self.alpha > 0.0: scores_for_aux = scores aux_topk = self.top_k topk_idx_for_aux_loss = topk_idx.view(bsz, -1) if self.seq_aux: scores_for_seq_aux = scores_for_aux.view(bsz, seq_len, -1) ce = torch.zeros(bsz, self.n_routed_experts, device=hidden_states.device) ce.scatter_add_(1, topk_idx_for_aux_loss, torch.ones(bsz, seq_len * aux_topk, device=hidden_states.device)).div_( seq_len * aux_topk / self.n_routed_experts) aux_loss = (ce * scores_for_seq_aux.mean(dim=1)).sum(dim=1).mean() * self.alpha else: mask_ce = F.one_hot(topk_idx_for_aux_loss.view(-1), num_classes=self.n_routed_experts) ce = mask_ce.float().mean(0) Pi = scores_for_aux.mean(0) fi = ce * self.n_routed_experts aux_loss = (Pi * fi).sum() * self.alpha else: aux_loss = 0 return topk_idx, topk_weight, aux_loss class MOEFeedForward(nn.Module): def __init__(self, config: LMConfig): super().__init__() self.config = config self.experts = nn.ModuleList([ FeedForward(config) for _ in range(config.n_routed_experts) ]) self.gate = MoEGate(config) if config.n_shared_experts is not None: self.shared_experts = FeedForward(config) def forward(self, x): identity = x orig_shape = x.shape bsz, seq_len, _ = x.shape # 使用门控机制选择专家 topk_idx, topk_weight, aux_loss = self.gate(x) x = x.view(-1, x.shape[-1]) flat_topk_idx = topk_idx.view(-1) if self.training: x = x.repeat_interleave(self.config.num_experts_per_tok, dim=0) y = torch.empty_like(x, dtype=torch.float16) for i, expert in enumerate(self.experts): y[flat_topk_idx == i] = expert(x[flat_topk_idx == i]).to(y.dtype) # 确保类型一致 y = (y.view(*topk_weight.shape, -1) * topk_weight.unsqueeze(-1)).sum(dim=1) y = y.view(*orig_shape) else: y = self.moe_infer(x, flat_topk_idx, topk_weight.view(-1, 1)).view(*orig_shape) if self.config.n_shared_experts is not None: y = y + self.shared_experts(identity) self.aux_loss = aux_loss return y @torch.no_grad() def moe_infer(self, x, flat_expert_indices, flat_expert_weights): expert_cache = torch.zeros_like(x) idxs = flat_expert_indices.argsort() tokens_per_expert = flat_expert_indices.bincount().cpu().numpy().cumsum(0) token_idxs = idxs // self.config.num_experts_per_tok # 当tokens_per_expert = [6, 15, 20, 26]，tokens_per_expert.shape[0]即为专家数量（此时为4） # 且token_idxs = [3, 7, 19, 21, 24, 25, 4, 5, 6, 10, 11, 12...] 时 # 意味token_idxs[:6] -> [3, 7, 19, 21, 24, 25]这6个位置属于专家0处理的token（每个token有可能被多个专家处理，这取决于num_experts_per_tok） # 接下来9个位置token_idxs[6:15] -> [4, 5, 6, 10, 11, 12...]属于专家1处理的token...依此类推 for i, end_idx in enumerate(tokens_per_expert): start_idx = 0 if i == 0 else tokens_per_expert[i - 1] if start_idx == end_idx: continue expert = self.experts[i] exp_token_idx = token_idxs[start_idx:end_idx] expert_tokens = x[exp_token_idx] expert_out = expert(expert_tokens).to(expert_cache.dtype) expert_out.mul_(flat_expert_weights[idxs[start_idx:end_idx]]) expert_cache.scatter_add_(0, exp_token_idx.view(-1, 1).repeat(1, x.shape[-1]), expert_out) return expert_cache class MiniMindBlock(nn.Module): def __init__(self, layer_id: int, config: LMConfig): super().__init__() self.n_heads = config.n_heads self.dim = config.dim self.head_dim = config.dim // config.n_heads self.attention = Attention(config) self.cross_att = CrossAttention(config) self.layer_id = layer_id self.attention_norm = RMSNorm(config.dim, eps=config.norm_eps) self.ffn_norm = RMSNorm(config.dim, eps=config.norm_eps) self.feed_forward = FeedForward(config) if not config.use_moe else MOEFeedForward(config) # 假设num_experts是已定义的总专家数量的平方根 # 查询生成的参数 # 创建查询生成模块 # if weight_down_embed is not None: # self.to_queries = nn.Sequential( # nn.Linear(config.dim, self.dim_key * 2, bias=False), # # nn.Unflatten(2, (2, self.n_heads, self.dim_key)) # 替代Rearrange # ) # # 超参数 # self.product_key_topk = min(16, self.num_keys) # 确保不超过num_keys # self.num_experts_per_head_topk = 1 # 最终每个头选取的专家数 def forward(self, x,db_value, pos_cis, past_key_value=None, use_cache=False): # import pdb;pdb.set_trace() # db_value = None # # 如果有weight_down_embed，使用Product Key机制 # if self.weight_down_embed is not None: # # 1. 生成queries # batch_size, seq_len, dim = x.shape # # collapse sequence dimension by averaging # x_flat = x.mean(dim=1) # [batch_size, dim] # queries = self.to_queries(x_flat) # [batch_size, 2*dim_key] # queries = queries.reshape(batch_size, 2, self.dim_key) # [batch_size, 2, dim_key] # queries = queries.permute(1, 0, 2) # [2, batch_size, dim_key] # # 2. 计算queries与keys的相似度 # sim = torch.einsum('p b d, k p d -> p b k', queries, self.keys) # # 3. 在两个子空间分别做top-k # scores_and_indices = [sim[p].topk(self.product_key_topk, dim=-1) for p in range(2)] # scores_x, scores_y = scores_and_indices[0][0], scores_and_indices[1][0] # indices_x, indices_y = scores_and_indices[0][1], scores_and_indices[1][1] # # 4. 组合两个子空间的分数和索引 # all_scores = scores_x.unsqueeze(-1) + scores_y.unsqueeze(-2) # all_scores = all_scores.view(*all_scores.shape[:-2], -1) # all_indices = (indices_x.unsqueeze(-1) * self.num_keys) + indices_y.unsqueeze(-2) # all_indices = all_indices.view(*all_indices.shape[:-2], -1) # # 5. 最终top-k选择 # scores, pk_indices = all_scores.topk(self.num_experts_per_head_topk, dim=-1) # indices = all_indices.gather(-1, pk_indices) # # 6. 从embedding中获取专家值 # # 从embedding中获取值 # flat_indices = indices.view(-1) # 将索引展平为一维张量 # db_values = self.weight_down_embed(flat_indices) # # 重塑回原始形状 # db_value = db_values.view(batch_size, -1, dim) # 注意力计算 h_attn, past_kv = self.attention( self.attention_norm(x), pos_cis, past_key_value=past_key_value, use_cache=use_cache, db_value=db_value ) h_attn = self.cross_att(h_attn,db_value) # 残差连接 h = x + h_attn # 前馈神经网络 out = h + self.feed_forward(self.ffn_norm(h)) return out, past_kv class ExtractDB(nn.Module): def __init__(self,params): # 修改专家数量和知识维度，确保能开方 super().__init__() self.batch_size = None self.dim = params.dim self.dim_key = self.dim // 2 self.num_experts = 10 * 10 # 1M专家，确保是完全平方数 # 将knowledge_dim设置为与head_dim相同，以便在attention中直接使用 self.head_dim = params.dim // params.n_heads self.knowledge_dim = 8*params.dim # 使用CPU上的普通tensor替代nn.Embedding self.register_buffer('weight_down_embed_cpu', torch.randn(self.num_experts, self.knowledge_dim, dtype=torch.float32, device='cpu') * 0.02, persistent=True) self.num_keys = int(math.sqrt(self.num_experts)) if self.num_experts > 0 else 0 self.product_key_topk = min(16, self.num_keys) self.keys = nn.Parameter(torch.randn(self.num_keys, 2, self.dim_key) * 0.02) self.num_experts_per_head_topk = 1 self.to_queries = nn.Sequential( nn.Linear(params.dim, self.dim_key * 2, bias=False), ) def q_to_k(self,x): # 1. 生成queries self.batch_size, seq_len, dim = x.shape # collapse sequence dimension by averaging x_flat = x.mean(dim=1) # [batch_size, dim] queries = self.to_queries(x_flat) # [batch_size, 2*dim_key] queries = queries.reshape(self.batch_size, 2, self.dim_key) # [batch_size, 2, dim_key] queries = queries.permute(1, 0, 2) # [2, batch_size, dim_key] # 2. 计算queries与keys的相似度 sim = torch.einsum('p b d, k p d -> p b k', queries, self.keys) # 3. 在两个子空间分别做top-k scores_and_indices = [sim[p].topk(self.product_key_topk, dim=-1) for p in range(2)] scores_x, scores_y = scores_and_indices[0][0], scores_and_indices[1][0] indices_x, indices_y = scores_and_indices[0][1], scores_and_indices[1][1] # 4. 组合两个子空间的分数和索引 all_scores = scores_x.unsqueeze(-1) + scores_y.unsqueeze(-2) all_scores = all_scores.view(*all_scores.shape[:-2], -1) all_indices = (indices_x.unsqueeze(-1) * self.num_keys) + indices_y.unsqueeze(-2) all_indices = all_indices.view(*all_indices.shape[:-2], -1) # 5. 最终top-k选择 scores, pk_indices = all_scores.topk(self.num_experts_per_head_topk, dim=-1) indices = all_indices.gather(-1, pk_indices) flat_indices = indices.view(-1) return flat_indices def get_data(self, index): # 将需要的embedding从CPU移到当前设备上 device = index.device # 根据索引获取对应的embedding db_values = self.weight_down_embed_cpu[index.cpu()].to(device) db_value = db_values.view(self.batch_size, -1, self.dim) return db_value def updata_value(self, k, v): # 更新CPU上的张量值 k_cpu = k.cpu() v_cpu = v.view(v.size(0), -1).cpu() # 直接更新内存中的值 self.weight_down_embed_cpu[k_cpu] = v_cpu class MiniMindLM(PreTrainedModel): config_class = LMConfig def __init__(self, params: LMConfig = None): self.params = params or LMConfig() super().__init__(self.params) self.vocab_size, self.n_layers = params.vocab_size, params.n_layers self.tok_embeddings = nn.Embedding(params.vocab_size, params.dim) self.dropout = nn.Dropout(params.dropout) # 移除旧的weight_down_embed声明 self.extract_db = ExtractDB(self.params) # 将self.weight_down_embed传递给每个MiniMindBlock self.layers = nn.ModuleList([MiniMindBlock(l, params) for l in range(self.n_layers)]) self.norm = RMSNorm(params.dim, eps=params.norm_eps) self.output = nn.Linear(params.dim, params.vocab_size, bias=False) self.tok_embeddings.weight = self.output.weight self.downsample_v = nn.Sequential( nn.Conv1d(511*8,128*8,kernel_size=1,padding='same'), nn.Conv1d(128*8,128,kernel_size=1,padding='same'), nn.Conv1d(128,8,kernel_size=1,padding='same') ) self.downsample_q = nn.Sequential( nn.Conv1d(511*8,128*8,kernel_size=1,padding='same'), nn.Conv1d(128*8,512,kernel_size=1,padding='same') ) self.register_buffer("pos_cis", precompute_pos_cis(dim=params.dim // params.n_heads, theta=params.rope_theta), persistent=False) self.OUT = CausalLMOutputWithPast() def forward(self, input_ids: Optional[torch.Tensor] = None, past_key_values: Optional[List[Tuple[torch.Tensor, torch.Tensor]]] = None, use_cache: bool = False, logits_to_keep: Union[int, torch.Tensor] = 0, **args): past_key_values = past_key_values or [None] * len(self.layers) start_pos = args.get('start_pos', 0) h = self.dropout(self.tok_embeddings(input_ids)) pos_cis = self.pos_cis[start_pos:start_pos + input_ids.size(1)] past_kvs = [] h_list = [] for l, layer in enumerate(self.layers): index = self.extract_db.q_to_k(h) db_value = self.extract_db.get_data(index) h, past_kv = layer( h,db_value, pos_cis, past_key_value=past_key_values[l], use_cache=use_cache ) past_kvs.append(past_kv) h_list.append(h.unsqueeze(0)) h_tensor = torch.cat(h_list,dim=0).permute(1,0,2,3) h_tensor = h_tensor.reshape(h_tensor.shape[0],-1,768) z_v = self.downsample_v(h_tensor) z_q = self.downsample_q(h_tensor) z_k = self.extract_db.q_to_k(z_q) self.extract_db.updata_value(z_k,z_v) #更新数据库 # q,v = f(h_list) slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep logits = self.output(self.norm(h)[:, slice_indices, :]) aux_loss = sum(l.feed_forward.aux_loss for l in self.layers if isinstance(l.feed_forward, MOEFeedForward)) self.OUT.__setitem__('last_hidden_state', h) self.OUT.__setitem__('logits', logits) self.OUT.__setitem__('aux_loss', aux_loss) self.OUT.__setitem__('past_key_values', past_kvs) return self.OUT @torch.inference_mode() def generate(self, input_ids, eos_token_id=2, max_new_tokens=1024, temperature=0.75, top_p=0.90, stream=False, rp=1., use_cache=True, pad_token_id=0, num_return_sequences=1, **args): # 流式生成 if stream: return self._stream(input_ids, eos_token_id, max_new_tokens, temperature, top_p, rp, use_cache, **args) # 直接生成 generated = [] for i in range(input_ids.size(0)): non_pad = input_ids[i][input_ids[i] != pad_token_id].unsqueeze(0) for _ in range(num_return_sequences): out = self._stream(non_pad, eos_token_id, max_new_tokens, temperature, top_p, rp, use_cache, **args) tokens_list = [tokens[:, -1:] for tokens in out] gen = torch.cat(tokens_list, dim=-1) if tokens_list else non_pad full_sequence = torch.cat([non_pad, gen], dim=-1) generated.append(full_sequence) max_length = max(seq.size(1) for seq in generated) generated = [ torch.cat( [seq, torch.full((1, max_length - seq.size(1)), pad_token_id, dtype=seq.dtype, device=seq.device)], dim=-1) for seq in generated ] output = torch.cat(generated, dim=0) res = output.view(input_ids.size(0) * num_return_sequences, -1) return res def _stream(self, input_ids, eos_token_id, max_new_tokens, temperature, top_p, rp, use_cache, **args): start, first_seq, past_kvs = input_ids.shape[1], True, None while input_ids.shape[1] < max_new_tokens - 1: if first_seq or not use_cache: out, first_seq = self(input_ids, past_key_values=past_kvs, use_cache=use_cache, **args), False else: out = self(input_ids[:, -1:], past_key_values=past_kvs, use_cache=use_cache, start_pos=input_ids.shape[1] - 1, **args) logits, past_kvs = out.logits[:, -1, :], out.past_key_values logits[:, list(set(input_ids.tolist()[0]))] /= rp logits /= (temperature + 1e-9) if top_p is not None and top_p < 1.0: sorted_logits, sorted_indices = torch.sort(logits, descending=True, dim=-1) sorted_probs = F.softmax(sorted_logits, dim=-1) cumulative_probs = torch.cumsum(sorted_probs, dim=-1) sorted_indices_to_remove = cumulative_probs > top_p sorted_indices_to_remove[:, 1:] = sorted_indices_to_remove[:, :-1].clone() sorted_indices_to_remove[:, 0] = False indices_to_remove = sorted_indices_to_remove.scatter(1, sorted_indices, sorted_indices_to_remove) logits[indices_to_remove] = -float('Inf') input_ids_next = torch.multinomial(F.softmax(logits, dim=-1), num_samples=1) input_ids = torch.cat((input_ids, input_ids_next), dim=1) yield input_ids[:, start:] if input_ids_next.item() == eos_token_id: break