[Speculators][Speculative Decoding] Add Eagle3 Support For HunYuan Model

tests/models/registry.py

@@ -564,6 +564,10 @@ def check_available_online(
                                             is_available_online=False,
                                             speculative_model="openbmb/MiniCPM-2B-sft-bf16",
                                             tokenizer="openbmb/MiniCPM-2B-sft-bf16"),
+    "Eagle3HunYuanDenseV1ForCausalLM": _HfExamplesInfo(
+        "tencent/Hunyuan-1.8B-Instruct",
+        speculative_model="AngelSlim/Hunyuan-1.8B-Instruct_eagle3",
+        tokenizer="tencent/Hunyuan-1.8B-Instruct"),
     "ErnieMTPModel": _HfExamplesInfo("baidu/ERNIE-4.5-21B-A3B-PT",
                                     trust_remote_code=True,
                                     speculative_model="baidu/ERNIE-4.5-21B-A3B-PT"),
@@ -573,7 +577,7 @@ def check_available_online(
                                         is_available_online=False),
     "MiMoMTPModel": _HfExamplesInfo("XiaomiMiMo/MiMo-7B-RL",
                                     trust_remote_code=True,
-                                    speculative_model="XiaomiMiMo/MiMo-7B-RL")
+                                    speculative_model="XiaomiMiMo/MiMo-7B-RL"),
 }
 
 _TRANSFORMERS_BACKEND_MODELS = {

tests/v1/e2e/test_spec_decode.py

@@ -130,6 +130,8 @@ def test_ngram_correctness(
     [
         # TODO: Re-enable this once tests/models/test_initialization.py is fixed, see PR #22333 #22611  # noqa: E501
         # (("eagle3", "Qwen/Qwen3-8B", "AngelSlim/Qwen3-8B_eagle3", 1), False),
+        (("eagle3", "tencent/Hunyuan-1.8B-Instruct",
+          "AngelSlim/Hunyuan-1.8B-Instruct_eagle3", 1), False),
         (("eagle", "meta-llama/Llama-3.1-8B-Instruct",
           "yuhuili/EAGLE-LLaMA3.1-Instruct-8B", 1), False),
         (("eagle3", "meta-llama/Llama-3.1-8B-Instruct",
@@ -150,6 +152,7 @@ def test_ngram_correctness(
     ids=[
         # TODO: Re-enable this once tests/models/test_initialization.py is fixed, see PR #22333 #22611  # noqa: E501
         # "qwen3_eagle3",
+        "hunyuan_eagle3",
         "llama3_eagle",
         "llama3_eagle3",
         "llama4_eagle",
@@ -193,6 +196,9 @@ def test_eagle_correctness(
 
         method, model_name, spec_model_name, tp_size = model_setup
 
+        if "Hunyuan" in model_name and attn_backend == "TREE_ATTN":
+            pytest.skip("TREE ATTN not support Hunyuan Model yet")
+
         ref_llm = LLM(model=model_name,
                       max_model_len=2048,
                       tensor_parallel_size=tp_size)

vllm/config/__init__.py

@@ -2400,7 +2400,7 @@ def _verify_args(self) -> Self:
                              "speculative decoding is > 1, but got "
                              f"{self.disable_by_batch_size=}")
 
-        eagle3_target_supported = ["llama", "qwen"]
+        eagle3_target_supported = ["llama", "qwen", "hunyuan"]
         if self.method == "eagle3" and self.target_model_config and not any(
                 supported_model in
                 self.target_model_config.hf_text_config.model_type

vllm/model_executor/models/hunyuan_v1.py

@@ -37,6 +37,7 @@
 from vllm.distributed import (get_pp_group,
                               get_tensor_model_parallel_world_size,
                               tensor_model_parallel_all_reduce)
+from vllm.logger import init_logger
 from vllm.model_executor.layers.activation import SiluAndMul
 from vllm.model_executor.layers.fused_moe import FusedMoE
 from vllm.model_executor.layers.layernorm import RMSNorm
@@ -60,6 +61,8 @@
 from .utils import (AutoWeightsLoader, PPMissingLayer, is_pp_missing_parameter,
                     make_layers)
 
+logger = init_logger(__name__)
+
 
 def _is_moe(config: PretrainedConfig) -> bool:
     num_experts = getattr(config, "num_experts", None)
@@ -215,7 +218,7 @@ def forward(
         positions: torch.Tensor,
         hidden_states: torch.Tensor,
         kv_states: Optional[tuple[torch.Tensor]] = None,
-    ) -> torch.Tensor:
+    ) -> tuple[torch.Tensor, tuple[torch.Tensor, torch.Tensor]]:
         qkv, _ = self.qkv_proj(hidden_states)
         q, k, v = qkv.split([self.q_size, self.kv_size, self.kv_size], dim=-1)
         q, k = self.rotary_emb(positions, q, k)
@@ -596,6 +599,8 @@ def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
         else:
             self.norm = PPMissingLayer()
 
+        self.aux_hidden_state_layers: tuple[int] = tuple()
+
     def get_input_embeddings(self, input_ids: torch.Tensor) -> torch.Tensor:
         return self.embed_tokens(input_ids)
 
@@ -619,8 +624,13 @@ def forward(
 
         cla_factor = _get_cla_factor(self.config)
         prev_kv_states = None
+        aux_hidden_states = []
         for i in range(self.start_layer, self.end_layer):
             layer = self.layers[i]
+            if i in self.aux_hidden_state_layers:
+                aux_hidden_states.append(hidden_states if residual is
+                                         None else hidden_states + residual)
+
             hidden_states, residual, kv_states = layer(
                 positions,
                 hidden_states,
@@ -641,6 +651,9 @@ def forward(
             })
 
         hidden_states, _ = self.norm(hidden_states, residual)
+
+        if len(aux_hidden_states) > 0:
+            return hidden_states, aux_hidden_states
         return hidden_states
 
     def _split_qkv_weight(self, qkv: torch.Tensor):
@@ -928,6 +941,13 @@ def load_weights(self, weights: Iterable[tuple[str,
     def get_expert_mapping(self) -> list[tuple[str, str, int, str]]:
         return self.model.get_expert_mapping()
 
+    def set_aux_hidden_state_layers(self, layers: tuple[int]) -> None:
+        self.model.aux_hidden_state_layers = layers
+
+    def get_eagle3_aux_hidden_state_layers(self) -> tuple[int]:
+        num_layers = len(self.model.layers)
+        return (2, num_layers // 2, num_layers - 3)
+
 
 class HunYuanDenseV1ForCausalLM(HunYuanV1Base):
     pass