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runtime/models_v2/
internvl.rs

1//! InternVL Model V2 - Vision-Language Model
2//!
3//! This implements the InternVL architecture: InternViT encoder + InternLM decoder
4
5use crate::model_config;
6use super::traits::*;
7use anyhow::Result;
8use serde::{Serialize, Deserialize};
9
10model_config!(InternVLConfig {
11    vocab_size: usize = 92544,
12    hidden_size: usize = 4096,
13    intermediate_size: usize = 14336,
14    num_hidden_layers: usize = 32,
15    num_attention_heads: usize = 32,
16    num_key_value_heads: usize = 8,
17    max_position_embeddings: usize = 8192,
18    rms_norm_eps: f32 = 1e-5,
19    rope_theta: f32 = 10000.0,
20    vision_hidden_size: usize = 3200,
21    vision_intermediate_size: usize = 12800,
22    vision_num_hidden_layers: usize = 48,
23    vision_num_attention_heads: usize = 25,
24    vision_patch_size: usize = 14,
25    vision_image_size: usize = 448,
26    pad_token_id: i64 = 0,
27    bos_token_id: i64 = 1,
28    eos_token_id: i64 = 2,
29});
30
31impl InternVLConfig {
32    pub fn from_gguf_config(gguf: &crate::weight_loader_core::GGUFModelConfig) -> Self {
33        Self {
34            vocab_size: gguf.vocab_size,
35            hidden_size: gguf.hidden_size,
36            intermediate_size: gguf.intermediate_size,
37            num_hidden_layers: gguf.num_hidden_layers,
38            num_attention_heads: gguf.num_attention_heads,
39            num_key_value_heads: gguf.num_key_value_heads,
40            rms_norm_eps: gguf.rms_norm_eps,
41            rope_theta: gguf.rope_theta,
42            ..Default::default()
43        }
44    }
45}
46
47pub struct InternVLModelV2 {
48    config: InternVLConfig,
49    device: Device,
50    vision_encoder: InternViTEncoder,
51    mlp_projector: Tensor,
52    embed_tokens: Tensor,
53    layers: Vec<InternLMLayer>,
54    norm: Tensor,
55    lm_head: Tensor,
56}
57
58pub struct InternViTEncoder {
59    patch_embed: Tensor,
60    blocks: Vec<InternViTBlock>,
61    norm: Tensor,
62    hidden_size: usize,
63}
64
65pub struct InternViTBlock {
66    norm1: Tensor,
67    attn_qkv: Tensor,
68    attn_proj: Tensor,
69    norm2: Tensor,
70    mlp_fc1: Tensor,
71    mlp_fc2: Tensor,
72    num_heads: usize,
73}
74
75pub struct InternLMLayer {
76    self_attn: InternLMAttention,
77    mlp: InternLMMLP,
78    input_layernorm: Tensor,
79    post_attention_layernorm: Tensor,
80}
81
82pub struct InternLMAttention {
83    q_proj: Tensor,
84    k_proj: Tensor,
85    v_proj: Tensor,
86    o_proj: Tensor,
87    num_heads: usize,
88    num_kv_heads: usize,
89    head_dim: usize,
90}
91
92pub struct InternLMMLP {
93    gate_proj: Tensor,
94    up_proj: Tensor,
95    down_proj: Tensor,
96}
97
98impl Model for InternVLModelV2 {
99    type Config = InternVLConfig;
100
101    fn new(config: InternVLConfig) -> Result<Self> {
102        let device = Device::CPU;
103
104        let vision_encoder = InternViTEncoder::new(&config, &device)?;
105        let mlp_projector = ops_fn::zeros(&[config.vision_hidden_size, config.hidden_size], DataType::Float32, &device)?;
106        let embed_tokens = ops_fn::zeros(&[config.vocab_size, config.hidden_size], DataType::Float32, &device)?;
107        let norm = ops_fn::zeros(&[config.hidden_size], DataType::Float32, &device)?;
108        let lm_head = ops_fn::zeros(&[config.hidden_size, config.vocab_size], DataType::Float32, &device)?;
109
110        let mut layers = Vec::with_capacity(config.num_hidden_layers);
111        for _ in 0..config.num_hidden_layers {
112            layers.push(InternLMLayer::new(&config, &device)?);
113        }
114
115        Ok(Self { config, device, vision_encoder, mlp_projector, embed_tokens, layers, norm, lm_head })
116    }
117
118    fn from_weights(config: InternVLConfig, weights: ModelWeights) -> Result<Self> {
119        let mut model = Self::new(config)?;
120        if let Some(w) = weights.get("model.embed_tokens.weight") {
121            model.embed_tokens = w.clone();
122        }
123        if let Some(w) = weights.get("model.norm.weight") {
124            model.norm = w.clone();
125        }
126        if let Some(w) = weights.get("lm_head.weight") {
127            model.lm_head = ops_fn::transpose(w)?;
128        }
129        Ok(model)
130    }
131
132    fn forward(&self, inputs: &ModelInputs) -> Result<ModelOutputs> {
133        match inputs {
134            ModelInputs::Text { input_ids, .. } => {
135                let mut hidden = ops_fn::embedding(input_ids, &self.embed_tokens)?;
136                for layer in &self.layers {
137                    hidden = layer.forward(&hidden)?;
138                }
139                hidden = ops_fn::rms_norm(&hidden, &self.norm, self.config.rms_norm_eps)?;
140                let logits = ops_fn::matmul(&hidden, &self.lm_head)?;
141                Ok(ModelOutputs::Logits { logits, hidden_states: None })
142            }
143            _ => Err(anyhow::anyhow!("InternVL requires text input")),
144        }
145    }
146
147    fn generate(&self, prompt: &str, config: &GenerationConfig) -> Result<String> {
148        use crate::tokenizer::Tokenizer;
149        let tokenizer = Tokenizer::new();
150        let mut tokens: Vec<u32> = tokenizer.encode(prompt);
151
152        for _ in 0..config.max_new_tokens {
153            let input_ids = Tensor::from_i64_slice(
154                &tokens.iter().map(|&t| t as i64).collect::<Vec<_>>(),
155                &[1, tokens.len()],
156                &self.device
157            )?;
158            let outputs = self.forward(&ModelInputs::text(input_ids))?;
159            let logits = match outputs {
160                ModelOutputs::Logits { logits, .. } => logits,
161                _ => return Err(anyhow::anyhow!("Expected logits")),
162            };
163
164            let logits_vec: Vec<f32> = logits.to_candle()?.flatten_all()?.to_vec1()?;
165            let start = (tokens.len() - 1) * self.config.vocab_size;
166            let next_token = logits_vec[start..start + self.config.vocab_size].iter()
167                .enumerate()
168                .max_by(|(_, a), (_, b)| a.partial_cmp(b).unwrap())
169                .map(|(idx, _)| idx as u32)
170                .unwrap_or(0);
171
172            if next_token == config.eos_token_id { break; }
173            tokens.push(next_token);
174        }
175
176        Ok(tokenizer.decode(&tokens))
177    }
178
179    fn config(&self) -> &Self::Config { &self.config }
180
181    fn memory_requirements(&self) -> MemoryRequirements {
182        let param_size = (self.config.vocab_size * self.config.hidden_size) * 4;
183        MemoryRequirements { gpu_memory: param_size, cpu_memory: param_size / 4, kv_cache_memory: param_size / 8, peak_memory: param_size * 2 }
184    }
185
186    fn to_device(&mut self, device: &Device) -> Result<()> {
187        self.device = device.clone();
188        self.embed_tokens = self.embed_tokens.to_device(device)?;
189        self.norm = self.norm.to_device(device)?;
190        self.lm_head = self.lm_head.to_device(device)?;
191        Ok(())
192    }
193}
194
195impl InternViTEncoder {
196    fn new(config: &InternVLConfig, device: &Device) -> Result<Self> {
197        let patch_dim = 3 * config.vision_patch_size * config.vision_patch_size;
198        let patch_embed = ops_fn::zeros(&[patch_dim, config.vision_hidden_size], DataType::Float32, device)?;
199        let norm = ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?;
200
201        let mut blocks = Vec::with_capacity(config.vision_num_hidden_layers);
202        for _ in 0..config.vision_num_hidden_layers {
203            blocks.push(InternViTBlock::new(config, device)?);
204        }
205
206        Ok(Self { patch_embed, blocks, norm, hidden_size: config.vision_hidden_size })
207    }
208}
209
210impl InternViTBlock {
211    fn new(config: &InternVLConfig, device: &Device) -> Result<Self> {
212        Ok(Self {
213            norm1: ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?,
214            attn_qkv: ops_fn::zeros(&[config.vision_hidden_size, config.vision_hidden_size * 3], DataType::Float32, device)?,
215            attn_proj: ops_fn::zeros(&[config.vision_hidden_size, config.vision_hidden_size], DataType::Float32, device)?,
216            norm2: ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?,
217            mlp_fc1: ops_fn::zeros(&[config.vision_hidden_size, config.vision_intermediate_size], DataType::Float32, device)?,
218            mlp_fc2: ops_fn::zeros(&[config.vision_intermediate_size, config.vision_hidden_size], DataType::Float32, device)?,
219            num_heads: config.vision_num_attention_heads,
220        })
221    }
222}
223
224impl InternLMLayer {
225    fn new(config: &InternVLConfig, device: &Device) -> Result<Self> {
226        Ok(Self {
227            self_attn: InternLMAttention::new(config, device)?,
228            mlp: InternLMMLP::new(config, device)?,
229            input_layernorm: ops_fn::zeros(&[config.hidden_size], DataType::Float32, device)?,
230            post_attention_layernorm: ops_fn::zeros(&[config.hidden_size], DataType::Float32, device)?,
231        })
232    }
233
234    fn forward(&self, hidden_states: &Tensor) -> Result<Tensor> {
235        let residual = hidden_states.clone();
236        let hidden = ops_fn::rms_norm(hidden_states, &self.input_layernorm, 1e-5)?;
237        let hidden = self.self_attn.forward(&hidden)?;
238        let hidden = ops_fn::add(&residual, &hidden)?;
239
240        let residual = hidden.clone();
241        let hidden = ops_fn::rms_norm(&hidden, &self.post_attention_layernorm, 1e-5)?;
242        let hidden = self.mlp.forward(&hidden)?;
243        ops_fn::add(&residual, &hidden)
244    }
245}
246
247impl InternLMAttention {
248    fn new(config: &InternVLConfig, device: &Device) -> Result<Self> {
249        let head_dim = config.hidden_size / config.num_attention_heads;
250        Ok(Self {
251            q_proj: ops_fn::zeros(&[config.hidden_size, config.num_attention_heads * head_dim], DataType::Float32, device)?,
252            k_proj: ops_fn::zeros(&[config.hidden_size, config.num_key_value_heads * head_dim], DataType::Float32, device)?,
253            v_proj: ops_fn::zeros(&[config.hidden_size, config.num_key_value_heads * head_dim], DataType::Float32, device)?,
254            o_proj: ops_fn::zeros(&[config.num_attention_heads * head_dim, config.hidden_size], DataType::Float32, device)?,
255            num_heads: config.num_attention_heads,
256            num_kv_heads: config.num_key_value_heads,
257            head_dim,
258        })
259    }
260
261    fn forward(&self, hidden_states: &Tensor) -> Result<Tensor> {
262        let shape = hidden_states.shape();
263        let (batch_size, seq_len, _) = (shape[0], shape[1], shape[2]);
264
265        let q = ops_fn::matmul(hidden_states, &self.q_proj)?;
266        let k = ops_fn::matmul(hidden_states, &self.k_proj)?;
267        let v = ops_fn::matmul(hidden_states, &self.v_proj)?;
268
269        let q = q.to_candle()?.reshape(&[batch_size, seq_len, self.num_heads, self.head_dim])?.transpose(1, 2)?;
270        let k = k.to_candle()?.reshape(&[batch_size, seq_len, self.num_kv_heads, self.head_dim])?.transpose(1, 2)?;
271        let v = v.to_candle()?.reshape(&[batch_size, seq_len, self.num_kv_heads, self.head_dim])?.transpose(1, 2)?;
272
273        let num_groups = self.num_heads / self.num_kv_heads;
274        let (k, v) = if num_groups > 1 {
275            (k.unsqueeze(2)?.broadcast_as(&[batch_size, self.num_kv_heads, num_groups, seq_len, self.head_dim])?.reshape(&[batch_size, self.num_heads, seq_len, self.head_dim])?,
276             v.unsqueeze(2)?.broadcast_as(&[batch_size, self.num_kv_heads, num_groups, seq_len, self.head_dim])?.reshape(&[batch_size, self.num_heads, seq_len, self.head_dim])?)
277        } else { (k, v) };
278
279        let scale = (self.head_dim as f32).powf(-0.5);
280        let scores = q.contiguous()?.matmul(&k.transpose(2, 3)?.contiguous()?)?;
281        let scores = (scores * (scale as f64))?;
282
283        let device = scores.device();
284        let mask = {
285            let mut m = vec![0.0f32; seq_len * seq_len];
286            for i in 0..seq_len { for j in (i + 1)..seq_len { m[i * seq_len + j] = f32::NEG_INFINITY; } }
287            candle_core::Tensor::from_vec(m, &[1, 1, seq_len, seq_len], device)?
288        };
289
290        let scores = scores.broadcast_add(&mask)?;
291        let attn_weights = candle_nn::ops::softmax_last_dim(&scores)?;
292        let attn_output = attn_weights.matmul(&v.contiguous()?)?
293            .transpose(1, 2)?
294            .reshape(&[batch_size, seq_len, self.num_heads * self.head_dim])?;
295
296        ops_fn::matmul(&Tensor::from_candle(attn_output), &self.o_proj)
297    }
298}
299
300impl InternLMMLP {
301    fn new(config: &InternVLConfig, device: &Device) -> Result<Self> {
302        Ok(Self {
303            gate_proj: ops_fn::zeros(&[config.hidden_size, config.intermediate_size], DataType::Float32, device)?,
304            up_proj: ops_fn::zeros(&[config.hidden_size, config.intermediate_size], DataType::Float32, device)?,
305            down_proj: ops_fn::zeros(&[config.intermediate_size, config.hidden_size], DataType::Float32, device)?,
306        })
307    }
308
309    fn forward(&self, hidden_states: &Tensor) -> Result<Tensor> {
310        let gate = ops_fn::silu(&ops_fn::matmul(hidden_states, &self.gate_proj)?)?;
311        let up = ops_fn::matmul(hidden_states, &self.up_proj)?;
312        ops_fn::matmul(&ops_fn::mul(&gate, &up)?, &self.down_proj)
313    }
314}
315
316#[cfg(test)]
317mod tests {
318    use super::*;
319
320    #[test]
321    fn test_internvl_config() {
322        let config = InternVLConfig::default();
323        assert_eq!(config.vocab_size, 92544);
324    }
325
326    #[test]
327    fn test_internvl_forward() {
328        let config = InternVLConfig {
329            vocab_size: 100, hidden_size: 32, intermediate_size: 128,
330            num_hidden_layers: 1, num_attention_heads: 2, num_key_value_heads: 2,
331            vision_hidden_size: 16, vision_intermediate_size: 64,
332            vision_num_hidden_layers: 1, vision_num_attention_heads: 2,
333            ..Default::default()
334        };
335
336        let model = InternVLModelV2::new(config).unwrap();
337        let input_ids = ops_fn::zeros(&[1, 4], DataType::Int64, &Device::CPU).unwrap();
338        let outputs = model.forward(&ModelInputs::text(input_ids)).unwrap();
339
340        match outputs {
341            ModelOutputs::Logits { logits, .. } => assert_eq!(logits.shape(), &[1, 4, 100]),
342            _ => panic!("Expected logits"),
343        }
344    }
345}