Hunyuan V1 Dense model support (#351)

ivanfioravanti · awni · web-flow · commit cfa74add1eb5 · 2025-08-06T13:47:06.000-07:00
* Add Hunyuan V1 Dense model and support for --trust-remote-code option in evaluate and convert.

* add explicit head dimension support in Hunyuan V1 Dense model for differences between
- 0.5B - 4B
- 1.8B - 7B

* remove unused sanitize method from Hunyuan V1 Dense model

* add lora

---------

Co-authored-by: Awni Hannun &lt;awni@apple.com&gt;
diff --git a/mlx_lm/convert.py b/mlx_lm/convert.py
@@ -209,6 +209,12 @@ def configure_parser() -> argparse.ArgumentParser:
         action="store_true",
         default=False,
     )
+    parser.add_argument(
+        "--trust-remote-code",
+        help="Trust remote code when loading tokenizer.",
+        action="store_true",
+        default=False,
+    )
     return parser
 
 
diff --git a/mlx_lm/evaluate.py b/mlx_lm/evaluate.py
@@ -71,9 +71,13 @@ def __init__(
         path_or_hf_repo: str,
         max_tokens: Optional[int] = None,
         use_chat_template: Optional[bool] = None,
+        trust_remote_code: bool = False,
     ) -> None:
         super().__init__()
-        self._model, self.tokenizer = load(path_or_hf_repo)
+        tokenizer_config = {"trust_remote_code": True if trust_remote_code else None}
+        self._model, self.tokenizer = load(
+            path_or_hf_repo, tokenizer_config=tokenizer_config
+        )
         self._max_tokens = max_tokens or self.tokenizer.model_max_length
         self._batch_size = 8
         self.use_chat_template = use_chat_template
@@ -378,6 +382,11 @@ def main():
         help="Confirm that you want to run tasks that execute untrusted code.",
         default=False,
     )
+    parser.add_argument(
+        "--trust-remote-code",
+        action="store_true",
+        help="Enable trusting remote code for tokenizer",
+    )
 
     args = parser.parse_args()
 
@@ -393,6 +402,7 @@ def main():
         args.model,
         max_tokens=args.max_tokens,
         use_chat_template=args.apply_chat_template,
+        trust_remote_code=args.trust_remote_code,
     )
     MLXLM.apply_chat_template = chat_template_fn(**args.chat_template_args)
 
diff --git a/mlx_lm/models/hunyuan_v1_dense.py b/mlx_lm/models/hunyuan_v1_dense.py
@@ -0,0 +1,224 @@
+# Copyright © 2023-2025 Apple Inc.
+
+from dataclasses import dataclass
+from typing import Any, Dict, Optional, Union
+
+import mlx.core as mx
+import mlx.nn as nn
+
+from .base import BaseModelArgs, create_attention_mask, scaled_dot_product_attention
+
+
+@dataclass
+class ModelArgs(BaseModelArgs):
+    model_type: str
+    vocab_size: int
+    hidden_size: int
+    num_hidden_layers: int
+    intermediate_size: int
+    num_attention_heads: int
+    num_key_value_heads: int
+    rms_norm_eps: float
+    rope_theta: float = 10000
+    max_position_embeddings: int = 32768
+    attention_bias: bool = False
+    use_qk_norm: bool = True
+    rope_scaling: Optional[Dict[str, Union[float, str]]] = None
+    tie_word_embeddings: bool = False
+    head_dim: Optional[int] = None
+
+    def __post_init__(self):
+        if self.rope_scaling:
+            required_keys = {"alpha", "factor", "type"}
+            if not all(key in self.rope_scaling for key in required_keys):
+                raise ValueError(f"rope_scaling must contain keys {required_keys}")
+
+
+class DynamicNTKAlphaRoPE(nn.Module):
+    def __init__(
+        self,
+        dims: int,
+        base: float = 10000,
+        scaling_alpha: float = 1.0,
+    ):
+        super().__init__()
+        self.dims = dims
+        base = base * scaling_alpha ** (dims / (dims - 2))
+        self._freqs = base ** (mx.arange(0, self.dims, 2) / self.dims)
+
+    def __call__(self, x, offset: int = 0):
+        return mx.fast.rope(
+            x,
+            self.dims,
+            traditional=False,
+            base=None,
+            scale=1.0,
+            offset=offset,
+            freqs=self._freqs,
+        )
+
+
+class Attention(nn.Module):
+    def __init__(self, args: ModelArgs):
+        super().__init__()
+
+        dim = args.hidden_size
+        self.n_heads = n_heads = args.num_attention_heads
+        self.n_kv_heads = n_kv_heads = args.num_key_value_heads
+
+        head_dim = (
+            args.head_dim if args.head_dim is not None else args.hidden_size // n_heads
+        )
+        self.head_dim = head_dim
+        self.scale = head_dim**-0.5
+
+        self.q_proj = nn.Linear(dim, n_heads * head_dim, bias=args.attention_bias)
+        self.k_proj = nn.Linear(dim, n_kv_heads * head_dim, bias=args.attention_bias)
+        self.v_proj = nn.Linear(dim, n_kv_heads * head_dim, bias=args.attention_bias)
+        self.o_proj = nn.Linear(n_heads * head_dim, dim, bias=args.attention_bias)
+
+        self.use_qk_norm = args.use_qk_norm
+        if self.use_qk_norm:
+            self.query_layernorm = nn.RMSNorm(head_dim, args.rms_norm_eps)
+            self.key_layernorm = nn.RMSNorm(head_dim, args.rms_norm_eps)
+
+        scaling_alpha = 1.0
+        if args.rope_scaling and "alpha" in args.rope_scaling:
+            scaling_alpha = args.rope_scaling["alpha"]
+
+        self.rope = DynamicNTKAlphaRoPE(
+            head_dim,
+            base=args.rope_theta,
+            scaling_alpha=scaling_alpha,
+        )
+
+    def __call__(
+        self,
+        x: mx.array,
+        mask: Optional[mx.array] = None,
+        cache: Optional[Any] = None,
+    ) -> mx.array:
+        B, L, D = x.shape
+
+        queries, keys, values = self.q_proj(x), self.k_proj(x), self.v_proj(x)
+
+        queries = queries.reshape(B, L, self.n_heads, self.head_dim).transpose(
+            0, 2, 1, 3
+        )
+        keys = keys.reshape(B, L, self.n_kv_heads, self.head_dim).transpose(0, 2, 1, 3)
+        values = values.reshape(B, L, self.n_kv_heads, self.head_dim).transpose(
+            0, 2, 1, 3
+        )
+
+        if cache is not None:
+            queries = self.rope(queries, offset=cache.offset)
+            keys = self.rope(keys, offset=cache.offset)
+        else:
+            queries = self.rope(queries)
+            keys = self.rope(keys)
+
+        if self.use_qk_norm:
+            queries = self.query_layernorm(queries)
+            keys = self.key_layernorm(keys)
+
+        if cache is not None:
+            keys, values = cache.update_and_fetch(keys, values)
+
+        output = scaled_dot_product_attention(
+            queries, keys, values, cache=cache, scale=self.scale, mask=mask
+        )
+
+        output = output.transpose(0, 2, 1, 3).reshape(B, L, -1)
+        return self.o_proj(output)
+
+
+class MLP(nn.Module):
+    def __init__(self, args: ModelArgs):
+        super().__init__()
+
+        dim = args.hidden_size
+        hidden_dim = args.intermediate_size
+
+        self.gate_proj = nn.Linear(dim, hidden_dim, bias=False)
+        self.down_proj = nn.Linear(hidden_dim, dim, bias=False)
+        self.up_proj = nn.Linear(dim, hidden_dim, bias=False)
+
+    def __call__(self, x) -> mx.array:
+        return self.down_proj(nn.silu(self.gate_proj(x)) * self.up_proj(x))
+
+
+class TransformerBlock(nn.Module):
+    def __init__(self, args: ModelArgs):
+        super().__init__()
+        self.num_attention_heads = args.num_attention_heads
+        self.hidden_size = args.hidden_size
+        self.self_attn = Attention(args)
+        self.mlp = MLP(args)
+        self.input_layernorm = nn.RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
+        self.post_attention_layernorm = nn.RMSNorm(
+            args.hidden_size, eps=args.rms_norm_eps
+        )
+        self.args = args
+
+    def __call__(
+        self,
+        x: mx.array,
+        mask: Optional[mx.array] = None,
+        cache: Optional[Any] = None,
+    ) -> mx.array:
+        r = self.self_attn(self.input_layernorm(x), mask, cache)
+        h = x + r
+        r = self.mlp(self.post_attention_layernorm(h))
+        out = h + r
+        return out
+
+
+class HunyuanV1DenseModel(nn.Module):
+    def __init__(self, args: ModelArgs):
+        super().__init__()
+        self.args = args
+        self.vocab_size = args.vocab_size
+        self.num_hidden_layers = args.num_hidden_layers
+        self.embed_tokens = nn.Embedding(args.vocab_size, args.hidden_size)
+        self.layers = [TransformerBlock(args) for _ in range(args.num_hidden_layers)]
+        self.norm = nn.RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
+
+    def __call__(
+        self,
+        inputs: mx.array,
+        mask: mx.array = None,
+        cache=None,
+    ):
+        h = self.embed_tokens(inputs)
+
+        if mask is None:
+            mask = create_attention_mask(h, cache)
+
+        if cache is None:
+            cache = [None] * len(self.layers)
+
+        for layer, c in zip(self.layers, cache):
+            h = layer(h, mask, c)
+
+        return self.norm(h)
+
+
+class Model(nn.Module):
+    def __init__(self, args: ModelArgs):
+        super().__init__()
+        self.args = args
+        self.model_type = args.model_type
+        self.model = HunyuanV1DenseModel(args)
+
+    def __call__(
+        self,
+        inputs: mx.array,
+        mask: mx.array = None,
+        cache=None,
+    ):
+        out = self.model(inputs, mask, cache)
+        return self.model.embed_tokens.as_linear(out)
+
+    @property
+    def layers(self):
+        return self.model.layers
diff --git a/mlx_lm/tuner/utils.py b/mlx_lm/tuner/utils.py
@@ -121,6 +121,7 @@ def to_lora(layer):
         "dots1",
         "smollm3",
         "exaone4",
+        "hunyuan_v1_dense",
     }:
         keys = {"self_attn.q_proj", "self_attn.v_proj"}
         if model.model_type in ["mixtral", "phimoe"]:
diff --git a/tests/test_models.py b/tests/test_models.py
@@ -1039,6 +1039,38 @@ def test_hunyuan(self):
             model, args.model_type, args.vocab_size, args.num_hidden_layers
         )
 
+    def test_hunyuan_v1_dense(self):
+        from mlx_lm.models import hunyuan_v1_dense
+
+        args = hunyuan_v1_dense.ModelArgs(
+            model_type="hunyuan_v1_dense",
+            hidden_size=128,
+            attention_bias=False,
+            intermediate_size=256,
+            num_attention_heads=4,
+            num_hidden_layers=4,
+            num_key_value_heads=2,
+            rms_norm_eps=1e-4,
+            rope_theta=1000,
+            vocab_size=1000,
+            use_qk_norm=True,
+            rope_scaling={
+                "alpha": 1000.0,
+                "factor": 1.0,
+                "type": "dynamic",
+                "beta_fast": 32,
+                "beta_slow": 1,
+                "mscale": 1.0,
+                "mscale_all_dim": 0.0,
+                "original_max_position_embeddings": 8192,
+            },
+            max_position_embeddings=32768,
+        )
+        model = hunyuan_v1_dense.Model(args)
+        self.model_test_runner(
+            model, args.model_type, args.vocab_size, args.num_hidden_layers
+        )
+
     def test_olmo2(self):
         from mlx_lm.models import olmo2
 
