[Model] Support IQuest-Coder-40B-Loop (#16348)
Co-authored-by: yxing <yxing@iquestlab.com> Co-authored-by: yzhu <yzhu@ubiquant.com> Co-authored-by: zelong518 <zelonghuang02@gmail.com>
This commit is contained in:
co-authored by
yxing
yzhu
zelong518
parent
d0092decb1
commit
7b682de870
@@ -463,6 +463,9 @@ class ModelConfig:
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self.num_attention_layers = self.num_hidden_layers
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if "LongcatFlashForCausalLM" in self.hf_config.architectures:
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self.num_attention_layers = self.num_hidden_layers * 2
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if "IQuestLoopCoderForCausalLM" in self.hf_config.architectures:
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loop_num = getattr(self.hf_text_config, "loop_num", 1)
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self.num_attention_layers = int(self.num_hidden_layers * int(loop_num))
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self.num_nextn_predict_layers = getattr(
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self.hf_text_config, "num_nextn_predict_layers", None
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)
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@@ -793,6 +793,13 @@ class FlashInferAttnBackend(AttentionBackend):
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v_scale=layer.v_scale_float,
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)
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else:
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# If `k`/`v` are not explicitly provided, fall back to the KV cache stored in
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# `forward_batch.token_to_kv_pool` for this layer. This enables attention over
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# previously cached context without re-materializing KV tensors (e.g., the
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# IQuestLoopCoder path uses token_to_kv_pool as the KV source).
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if k is None and v is None:
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k = forward_batch.token_to_kv_pool.get_kv_buffer(layer.layer_id)[0]
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v = forward_batch.token_to_kv_pool.get_kv_buffer(layer.layer_id)[1]
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causal = True
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if (
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layer.is_cross_attention
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@@ -485,6 +485,12 @@ class ModelRunner(ModelRunnerKVCacheMixin):
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self.start_layer = getattr(self.model, "start_layer", 0)
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self.end_layer = getattr(self.model, "end_layer", model_num_layers)
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self.num_effective_layers = self.end_layer - self.start_layer
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# For LoopCoder models, each loop has its own layer_id, so we need to multiply by loop_num
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loop_num = getattr(self.model_config.hf_config, "loop_num", 1)
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if loop_num > 1:
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self.num_effective_layers = self.num_effective_layers * loop_num
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assert (
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(not model_has_mtp_layers)
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or (self.spec_algorithm.is_none())
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@@ -0,0 +1,498 @@
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# Copyright 2023-2024 SGLang Team
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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# ==============================================================================
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"""Inference-only LoopCoder model compatible with HuggingFace weights."""
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import logging
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from typing import Iterable, Optional, Tuple
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import torch
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from torch import nn
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from transformers import PretrainedConfig
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from sglang.srt.distributed import get_tensor_model_parallel_world_size
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from sglang.srt.layers.layernorm import RMSNorm
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from sglang.srt.layers.linear import (
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ColumnParallelLinear,
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QKVParallelLinear,
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RowParallelLinear,
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)
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from sglang.srt.layers.logits_processor import LogitsProcessor
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from sglang.srt.layers.quantization.base_config import QuantizationConfig
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from sglang.srt.layers.radix_attention import RadixAttention
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from sglang.srt.layers.rotary_embedding import get_rope
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from sglang.srt.layers.vocab_parallel_embedding import (
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ParallelLMHead,
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VocabParallelEmbedding,
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)
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from sglang.srt.model_executor.forward_batch_info import ForwardBatch
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from sglang.srt.model_loader.weight_utils import default_weight_loader
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from sglang.srt.models.llama import LlamaMLP as LoopCoderMLP
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from sglang.srt.utils import add_prefix, make_layers
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logger = logging.getLogger(__name__)
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class LoopGateProjection(nn.Module):
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"""Gate projection for mixed attention in Loop 2+.
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Computes: g = sigmoid(linear(Q)) for each head independently.
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This gate determines how much to use Loop1's KV (global) vs current loop's KV (local).
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Supports tensor parallelism: each GPU handles a subset of heads.
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The weight matrix has shape [num_heads, head_dim] and is split along the head dimension.
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"""
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def __init__(
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self,
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total_num_heads: int,
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head_dim: int,
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quant_config: Optional[QuantizationConfig] = None,
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prefix: str = "",
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):
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super().__init__()
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self.total_num_heads = total_num_heads
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self.head_dim = head_dim
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tp_size = get_tensor_model_parallel_world_size()
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assert self.total_num_heads % tp_size == 0
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self.num_heads = self.total_num_heads // tp_size
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self.gate_proj = ColumnParallelLinear(
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head_dim,
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self.total_num_heads,
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bias=True,
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gather_output=False,
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quant_config=quant_config,
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prefix=add_prefix("gate_proj", prefix),
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)
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def forward(self, query: torch.Tensor) -> torch.Tensor:
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"""Compute gate values from query tensor.
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Args:
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query: [num_heads, num_tokens, head_dim]
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where num_heads is the number of heads on this TP rank
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and num_tokens = batch * seq_len
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Returns:
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gate: [num_tokens, num_heads * head_dim] (flattened format matching q shape)
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"""
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num_heads, num_tokens, head_dim = query.shape
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assert (
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num_heads == self.num_heads
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), f"Expected {self.num_heads} heads, got {num_heads}"
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query_flat = query.reshape(-1, head_dim)
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gate_logits_flat, _ = self.gate_proj(query_flat)
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gate_logits = gate_logits_flat.reshape(num_heads, num_tokens, self.num_heads)
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# Extract diagonal: each head h's query should use output column h
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gate_logits = torch.diagonal(gate_logits, dim1=0, dim2=2)
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gate_logits = gate_logits.transpose(0, 1)
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gate_logits = gate_logits.unsqueeze(-1)
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# Apply sigmoid
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gate = torch.sigmoid(gate_logits)
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# Expand and reshape to match q shape: [num_tokens, num_heads * head_dim]
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gate = gate.transpose(0, 1)
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gate = gate.expand(-1, -1, head_dim)
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gate = gate.reshape(num_tokens, num_heads * head_dim)
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return gate
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class LoopCoderAttention(nn.Module):
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def __init__(
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self,
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config: PretrainedConfig,
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hidden_size: int,
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num_heads: int,
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num_kv_heads: int,
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layer_id: int = 0,
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max_position: int = 4096 * 32,
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quant_config: Optional[QuantizationConfig] = None,
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prefix: str = "",
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) -> None:
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super().__init__()
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self.layer_id = layer_id
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self.hidden_size = hidden_size
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tp_size = get_tensor_model_parallel_world_size()
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self.total_num_heads = num_heads
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assert self.total_num_heads % tp_size == 0
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self.num_heads = self.total_num_heads // tp_size
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self.total_num_kv_heads = num_kv_heads
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if self.total_num_kv_heads >= tp_size:
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assert self.total_num_kv_heads % tp_size == 0
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else:
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assert tp_size % self.total_num_kv_heads == 0
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self.num_kv_heads = max(1, self.total_num_kv_heads // tp_size)
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self.head_dim = hidden_size // self.total_num_heads
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self.q_size = self.num_heads * self.head_dim
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self.kv_size = self.num_kv_heads * self.head_dim
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self.scaling = self.head_dim**-0.5
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# Get loop_num from config, default to 2 if not specified
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self.loop_num = getattr(config, "loop_num", 2)
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self.loop_window_size = getattr(config, "loop_window_size", 64)
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self.qkv_proj = QKVParallelLinear(
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hidden_size,
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self.head_dim,
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self.total_num_heads,
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self.total_num_kv_heads,
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bias=False,
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quant_config=quant_config,
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prefix=add_prefix("qkv_proj", prefix),
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)
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self.o_proj = RowParallelLinear(
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self.total_num_heads * self.head_dim,
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hidden_size,
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bias=False,
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quant_config=quant_config,
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prefix=add_prefix("o_proj", prefix),
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)
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rope_theta = getattr(config, "rope_theta", 10000)
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rope_scaling = getattr(config, "rope_scaling", None)
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max_position_embeddings = getattr(
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config, "max_position_embeddings", max_position
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)
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self.rotary_emb = get_rope(
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self.head_dim,
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rotary_dim=self.head_dim,
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max_position=max_position_embeddings,
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base=rope_theta,
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rope_scaling=rope_scaling,
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)
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# Create attention instances for each loop
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# Loop 0: global attention without sliding window for full context
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# Loop 1+: local attention with sliding window for recent tokens
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# Each loop needs a unique layer_id to avoid KV cache conflicts
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self.attn = nn.ModuleList()
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total_layers = getattr(config, "num_hidden_layers", 24)
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for loop_idx in range(self.loop_num):
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sliding_window = -1 if loop_idx == 0 else self.loop_window_size
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# Use unique layer_id for each loop: loop_idx * total_layers + layer_id
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# This ensures each loop has its own KV cache space
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unique_layer_id = loop_idx * total_layers + layer_id
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self.attn.append(
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RadixAttention(
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self.num_heads,
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self.head_dim,
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self.scaling,
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num_kv_heads=self.num_kv_heads,
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layer_id=unique_layer_id, # Unique layer_id for each loop
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sliding_window_size=sliding_window,
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quant_config=quant_config,
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prefix=add_prefix(f"attn.{loop_idx}", prefix),
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)
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)
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def forward(
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self,
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positions: torch.Tensor,
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hidden_states: torch.Tensor,
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forward_batch: ForwardBatch,
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loop_idx: int,
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gate_proj: Optional[LoopGateProjection] = None,
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) -> torch.Tensor:
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qkv, _ = self.qkv_proj(hidden_states)
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q, k, v = qkv.split([self.q_size, self.kv_size, self.kv_size], dim=-1)
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q, k = self.rotary_emb(positions, q, k)
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if loop_idx == 0:
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# First loop: standard global attention, save KV to cache
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attn_output = self.attn[0](q, k, v, forward_batch)
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else:
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# Loop 2+: mixed attention with learned gating
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# Global attention: read from Loop 0's KV cache without updating (save_kv_cache=False)
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# This provides full context information
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# Pass k=None, v=None to read from KV cache instead of recomputing
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global_attn_output = self.attn[0](
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q, None, None, forward_batch, save_kv_cache=False
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)
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# Local attention: use current loop's KV with sliding window
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# This focuses on recent tokens within the window
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local_attn_output = self.attn[loop_idx](q, k, v, forward_batch)
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# Compute gating weights using query-dependent projection
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assert gate_proj is not None, "gate_proj must be provided for loop_idx > 0"
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num_tokens = q.shape[0]
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q_reshaped = q.view(num_tokens, self.num_heads, self.head_dim).transpose(
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0, 1
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)
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gate = gate_proj(q_reshaped)
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# Mix global and local attention outputs with learned gate
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# gate controls the balance between global context and local focus
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attn_output = global_attn_output * gate + local_attn_output * (1 - gate)
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output, _ = self.o_proj(attn_output)
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return output
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class LoopCoderDecoderLayer(nn.Module):
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def __init__(
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self,
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config: PretrainedConfig,
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layer_id: int = 0,
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quant_config: Optional[QuantizationConfig] = None,
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prefix: str = "",
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) -> None:
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super().__init__()
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self.hidden_size = config.hidden_size
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self.layer_id = layer_id
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self.self_attn = LoopCoderAttention(
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config=config,
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hidden_size=self.hidden_size,
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num_heads=config.num_attention_heads,
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num_kv_heads=config.num_key_value_heads,
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layer_id=layer_id,
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max_position=getattr(config, "max_position_embeddings", 4096 * 32),
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quant_config=quant_config,
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prefix=add_prefix("self_attn", prefix),
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)
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self.mlp = LoopCoderMLP(
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hidden_size=self.hidden_size,
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intermediate_size=config.intermediate_size,
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hidden_act=config.hidden_act,
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quant_config=quant_config,
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prefix=add_prefix("mlp", prefix),
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)
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self.input_layernorm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
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self.post_attention_layernorm = RMSNorm(
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config.hidden_size, eps=config.rms_norm_eps
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)
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def forward(
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self,
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positions: torch.Tensor,
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hidden_states: torch.Tensor,
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forward_batch: ForwardBatch,
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loop_idx: int,
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gate_proj: Optional[LoopGateProjection] = None,
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) -> torch.Tensor:
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# Self Attention
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residual = hidden_states
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hidden_states = self.input_layernorm(hidden_states)
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hidden_states = self.self_attn(
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positions=positions,
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hidden_states=hidden_states,
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forward_batch=forward_batch,
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loop_idx=loop_idx,
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gate_proj=gate_proj,
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)
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hidden_states = hidden_states + residual
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# MLP
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residual = hidden_states
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hidden_states = self.post_attention_layernorm(hidden_states)
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hidden_states = self.mlp(hidden_states)
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hidden_states = hidden_states + residual
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return hidden_states
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class IQuestLoopCoderModel(nn.Module):
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def __init__(
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self,
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config: PretrainedConfig,
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quant_config: Optional[QuantizationConfig] = None,
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prefix: str = "",
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):
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super().__init__()
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self.config = config
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self.quant_config = quant_config
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self.vocab_size = config.vocab_size
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self.embed_tokens = VocabParallelEmbedding(
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config.vocab_size,
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config.hidden_size,
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quant_config=quant_config,
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prefix=add_prefix("embed_tokens", prefix),
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)
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self.loop_num = getattr(self.config, "loop_num", 2)
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self.window_size = getattr(self.config, "loop_window_size", 64)
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# Gate projections for Loop 2+ (one per layer)
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head_dim = config.hidden_size // config.num_attention_heads
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gate_projections = make_layers(
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config.num_hidden_layers,
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lambda idx, prefix: LoopGateProjection(
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total_num_heads=config.num_attention_heads,
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head_dim=head_dim,
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quant_config=quant_config,
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prefix=prefix,
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),
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prefix=add_prefix("gate_projections", prefix),
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)
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if isinstance(gate_projections, tuple):
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self.start_layer, self.end_layer, self.gate_projections = gate_projections
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else:
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self.start_layer, self.end_layer = 0, config.num_hidden_layers
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self.gate_projections = gate_projections
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layers = make_layers(
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config.num_hidden_layers,
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lambda idx, prefix: LoopCoderDecoderLayer(
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config=config,
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layer_id=idx,
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quant_config=quant_config,
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prefix=prefix,
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),
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prefix=add_prefix("layers", prefix),
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)
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if isinstance(layers, tuple):
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self.start_layer, self.end_layer, self.layers = layers
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else:
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self.start_layer, self.end_layer = 0, config.num_hidden_layers
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self.layers = layers
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self.norm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
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def forward(
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self,
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input_ids: torch.Tensor,
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positions: torch.Tensor,
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forward_batch: ForwardBatch,
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input_embeds: torch.Tensor = None,
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) -> torch.Tensor:
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if input_embeds is not None:
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hidden_states = input_embeds
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else:
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hidden_states = self.embed_tokens(input_ids)
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# Multi-loop forward pass
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for loop_idx in range(self.loop_num):
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for layer_idx in range(self.start_layer, self.end_layer):
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layer = self.layers[layer_idx]
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# Get gate_proj for this layer (only for loop_idx > 0)
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gate_proj = self.gate_projections[layer_idx] if loop_idx > 0 else None
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hidden_states = layer(
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positions, hidden_states, forward_batch, loop_idx, gate_proj
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)
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hidden_states = self.norm(hidden_states)
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return hidden_states
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class IQuestLoopCoderForCausalLM(nn.Module):
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def __init__(
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self,
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config: PretrainedConfig,
|
||||
quant_config: Optional[QuantizationConfig] = None,
|
||||
prefix: str = "",
|
||||
):
|
||||
super().__init__()
|
||||
self.config = config
|
||||
self.quant_config = quant_config
|
||||
|
||||
self.model = IQuestLoopCoderModel(
|
||||
config=config,
|
||||
quant_config=quant_config,
|
||||
prefix=add_prefix("model", prefix),
|
||||
)
|
||||
|
||||
if config.tie_word_embeddings:
|
||||
self.lm_head = self.model.embed_tokens
|
||||
else:
|
||||
self.lm_head = ParallelLMHead(
|
||||
config.vocab_size,
|
||||
config.hidden_size,
|
||||
quant_config=quant_config,
|
||||
prefix=add_prefix("lm_head", prefix),
|
||||
)
|
||||
|
||||
self.logits_processor = LogitsProcessor(config)
|
||||
|
||||
@torch.no_grad()
|
||||
def forward(
|
||||
self,
|
||||
input_ids: torch.Tensor,
|
||||
positions: torch.Tensor,
|
||||
forward_batch: ForwardBatch,
|
||||
input_embeds: torch.Tensor = None,
|
||||
):
|
||||
hidden_states = self.model(input_ids, positions, forward_batch, input_embeds)
|
||||
return self.logits_processor(
|
||||
input_ids, hidden_states, self.lm_head, forward_batch
|
||||
)
|
||||
|
||||
def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
|
||||
stacked_params_mapping = [
|
||||
("qkv_proj", "q_proj", "q"),
|
||||
("qkv_proj", "k_proj", "k"),
|
||||
("qkv_proj", "v_proj", "v"),
|
||||
("gate_up_proj", "gate_proj", 0),
|
||||
("gate_up_proj", "up_proj", 1),
|
||||
]
|
||||
params_dict = dict(self.named_parameters())
|
||||
for name, loaded_weight in weights:
|
||||
if "rotary_emb.inv_freq" in name:
|
||||
continue
|
||||
|
||||
# Handle gate_projections weights
|
||||
if name.startswith("gate_projections."):
|
||||
if name.endswith(".weight"):
|
||||
sglang_name = name.replace(".weight", ".gate_proj.weight")
|
||||
elif name.endswith(".bias"):
|
||||
sglang_name = name.replace(".bias", ".gate_proj.bias")
|
||||
else:
|
||||
continue
|
||||
|
||||
if sglang_name in params_dict:
|
||||
param = params_dict[sglang_name]
|
||||
weight_loader = getattr(
|
||||
param, "weight_loader", default_weight_loader
|
||||
)
|
||||
weight_loader(param, loaded_weight)
|
||||
continue
|
||||
|
||||
# Handle stacked parameters
|
||||
for param_name, weight_name, shard_id in stacked_params_mapping:
|
||||
if weight_name not in name:
|
||||
continue
|
||||
name = name.replace(weight_name, param_name)
|
||||
if name.endswith(".bias") and name not in params_dict:
|
||||
continue
|
||||
if name in params_dict:
|
||||
param = params_dict[name]
|
||||
weight_loader = getattr(
|
||||
param, "weight_loader", default_weight_loader
|
||||
)
|
||||
weight_loader(param, loaded_weight, shard_id)
|
||||
break
|
||||
else:
|
||||
# Handle regular parameters
|
||||
if name.endswith(".bias") and name not in params_dict:
|
||||
continue
|
||||
if name in params_dict:
|
||||
param = params_dict[name]
|
||||
weight_loader = getattr(
|
||||
param, "weight_loader", default_weight_loader
|
||||
)
|
||||
weight_loader(param, loaded_weight)
|
||||
|
||||
|
||||
# Entry class for model registration
|
||||
EntryClass = IQuestLoopCoderForCausalLM
|
||||
@@ -794,4 +794,13 @@ class InternLM3ForCausalLM(LlamaForCausalLM):
|
||||
pass
|
||||
|
||||
|
||||
EntryClass = [LlamaForCausalLM, Phi3ForCausalLM, InternLM3ForCausalLM]
|
||||
class IQuestCoderForCausalLM(LlamaForCausalLM):
|
||||
pass
|
||||
|
||||
|
||||
EntryClass = [
|
||||
LlamaForCausalLM,
|
||||
Phi3ForCausalLM,
|
||||
InternLM3ForCausalLM,
|
||||
IQuestCoderForCausalLM,
|
||||
]
|
||||
|
||||
Reference in New Issue
Block a user