Add some llama-3.2 examples. (#2508)

* Add some llama-3.2 examples.

* Support tie-word-embeddings for llama.

2 files changed, 13 insertions, 1 deletions

diff --git a/candle-transformers/src/models/llama.rs b/candle-transformers/src/models/llama.rs
index e96bb855..a7bef099 100644
--- a/candle-transformers/src/models/llama.rs
+++ b/candle-transformers/src/models/llama.rs
@@ -44,6 +44,7 @@ pub struct LlamaConfig {
     pub eos_token_id: Option<LlamaEosToks>,
     pub rope_scaling: Option<Llama3RopeConfig>,
     pub max_position_embeddings: usize,
+    pub tie_word_embeddings: Option<bool>,
 }
 
 impl LlamaConfig {
@@ -72,6 +73,7 @@ impl LlamaConfig {
             eos_token_id: self.eos_token_id,
             rope_scaling: self.rope_scaling,
             max_position_embeddings: self.max_position_embeddings,
+            tie_word_embeddings: self.tie_word_embeddings.unwrap_or(false),
         }
     }
 }
@@ -91,6 +93,7 @@ pub struct Config {
     pub eos_token_id: Option<LlamaEosToks>,
     pub rope_scaling: Option<Llama3RopeConfig>,
     pub max_position_embeddings: usize,
+    pub tie_word_embeddings: bool,
 }
 
 impl Config {
@@ -109,6 +112,7 @@ impl Config {
             eos_token_id: None,
             rope_scaling: None,
             max_position_embeddings: DEFAULT_MAX_SEQ_LEN,
+            tie_word_embeddings: false,
         }
     }
 
@@ -127,6 +131,7 @@ impl Config {
             eos_token_id: None,
             rope_scaling: None,
             max_position_embeddings: DEFAULT_MAX_SEQ_LEN,
+            tie_word_embeddings: false,
         }
     }
 }
@@ -504,7 +509,11 @@ impl Llama {
 
     pub fn load(vb: VarBuilder, cfg: &Config) -> Result<Self> {
         let wte = embedding(cfg.vocab_size, cfg.hidden_size, vb.pp("model.embed_tokens"))?;
-        let lm_head = linear(cfg.hidden_size, cfg.vocab_size, vb.pp("lm_head"))?;
+        let lm_head = if cfg.tie_word_embeddings {
+            Linear::from_weights(wte.embeddings().clone(), None)
+        } else {
+            linear(cfg.hidden_size, cfg.vocab_size, vb.pp("lm_head"))?
+        };
         let ln_f = RmsNorm::new(cfg.hidden_size, cfg.rms_norm_eps, vb.pp("model.norm"))?;
         let blocks: Vec<_> = (0..cfg.num_hidden_layers)
             .map(|i| Block::load(vb.pp(format!("model.layers.{i}")), cfg).unwrap())
diff --git a/candle-transformers/src/models/llava/config.rs b/candle-transformers/src/models/llava/config.rs
index 5dca6870..405eedb9 100644
--- a/candle-transformers/src/models/llava/config.rs
+++ b/candle-transformers/src/models/llava/config.rs
@@ -43,6 +43,7 @@ pub struct LLaVAConfig {
     pub image_token_index: isize,
     #[serde(default = "default_hf")]
     pub hf: bool,
+    pub tie_word_embeddings: Option<bool>,
 }
 
 fn default_hf() -> bool {
@@ -77,6 +78,7 @@ impl LLaVAConfig {
             use_flash_attn: false,
             rope_scaling: None, // Assume we don't have LLaVA for Llama 3.1
             max_position_embeddings: self.max_position_embeddings,
+            tie_word_embeddings: self.tie_word_embeddings.unwrap_or(false),
         }
     }
 }
@@ -264,6 +266,7 @@ impl HFLLaVAConfig {
             use_cache: self.text_config.use_cache,
             vocab_size: self.vocab_size,
             image_token_index: self.image_token_index,
+            tie_word_embeddings: None,
         }
     }
 }