mirror of
https://github.com/huggingface/candle.git
synced 2025-06-16 10:38:54 +00:00
Refactor the llama example to make it more in sync with the other ones. (#139)
* Refactor the llama example to make it more in sync with the other ones. * Make clippy happy. * Properly load the safetensor weights. * Get llama back to a working state for the safetensors case.
This commit is contained in:
@ -20,11 +20,10 @@ use rand::{distributions::Distribution, SeedableRng};
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use candle::{DType, Device, Tensor, D};
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use candle_hub::{api::sync::Api, Repo, RepoType};
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use std::collections::HashMap;
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use std::sync::{Arc, Mutex};
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use candle_nn::VarBuilder;
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mod var_store;
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mod weights;
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mod model;
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use model::{Config, Llama};
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const MAX_SEQ_LEN: usize = 4096;
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#[cfg(feature = "mkl")]
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@ -83,337 +82,6 @@ Whate'er it bodes, henceforward will I bear
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Upon my target three fair-shining suns.
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";
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#[allow(dead_code)]
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struct Config {
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block_size: usize,
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vocab_size: usize,
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n_layer: usize,
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n_head: usize,
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n_embd: usize,
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}
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#[allow(dead_code)]
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impl Config {
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fn config_7b() -> Self {
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Self {
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block_size: 4096,
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vocab_size: 32000,
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n_layer: 32,
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n_head: 32,
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n_embd: 4096,
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}
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}
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fn config_13b() -> Self {
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Self {
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block_size: 4096,
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vocab_size: 32000,
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n_layer: 40,
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n_head: 40,
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n_embd: 5120,
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}
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}
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fn config_30b() -> Self {
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Self {
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block_size: 4096,
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vocab_size: 32000,
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n_layer: 60,
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n_head: 52,
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n_embd: 6656,
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}
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}
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fn config_65b() -> Self {
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Self {
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block_size: 4096,
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vocab_size: 32000,
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n_layer: 80,
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n_head: 64,
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n_embd: 8192,
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}
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}
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}
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struct Embedding {
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embeddings: Tensor,
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}
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impl Embedding {
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fn new(embeddings: Tensor) -> Self {
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Self { embeddings }
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}
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fn forward(&self, indexes: &Tensor) -> Result<Tensor> {
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let embeddings = self.embeddings.to_dtype(DTYPE)?;
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Ok(Tensor::embedding(indexes, &embeddings)?)
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}
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}
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struct Linear {
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weight: Tensor,
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}
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impl Linear {
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fn new(weight: Tensor) -> Self {
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Self { weight }
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}
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fn forward(&self, x: &Tensor) -> Result<Tensor> {
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let weight = self.weight.to_dtype(DTYPE)?;
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let x = x.matmul(&weight.t()?)?;
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Ok(x)
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}
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}
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struct RmsNorm {
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scale: Tensor,
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}
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impl RmsNorm {
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fn new(scale: Tensor) -> Self {
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Self { scale }
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}
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fn forward(&self, x: &Tensor) -> Result<Tensor> {
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// This is a no-op if x's dtype is already f32.
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let x = x.to_dtype(DType::F32)?;
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let (seq_len, hidden_size) = x.shape().r2()?;
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let norm_x = ((&x * &x)?.sum(&[1])? / hidden_size as f64)?;
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let norm_x = norm_x.broadcast_as((seq_len, hidden_size))?;
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let x_normed = (x / (norm_x + 1e-5)?.sqrt()?)?;
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let size = self.scale.shape().r1()?;
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let scale = self
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.scale
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.to_dtype(DType::F32)?
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.broadcast_as((seq_len, size))?;
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let x = (scale * x_normed)?;
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let x = x.to_dtype(DTYPE)?;
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Ok(x)
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}
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}
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struct Mlp {
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c_fc1: Linear,
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c_fc2: Linear,
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c_proj: Linear,
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}
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fn silu(xs: &Tensor) -> Result<Tensor> {
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Ok((xs / (xs.neg()?.exp()? + 1.0)?)?)
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}
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impl Mlp {
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fn new(c_fc1: Linear, c_fc2: Linear, c_proj: Linear) -> Self {
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Self {
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c_fc1,
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c_fc2,
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c_proj,
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}
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}
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fn forward(&self, x: &Tensor) -> Result<Tensor> {
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let x = (silu(&self.c_fc1.forward(x)?)? * self.c_fc2.forward(x)?)?;
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self.c_proj.forward(&x)
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}
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}
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fn masked_fill(on_false: &Tensor, mask: &Tensor, on_true: f32) -> Result<Tensor> {
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let shape = mask.shape();
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let on_true = Tensor::new(on_true, &on_false.device())?.broadcast_as(shape.dims())?;
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let m = mask.where_cond(&on_true, on_false)?;
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Ok(m)
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}
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#[derive(Clone)]
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struct Cache {
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masks: Arc<Mutex<HashMap<usize, Tensor>>>,
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use_kv_cache: bool,
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#[allow(clippy::type_complexity)]
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kvs: Arc<Mutex<Vec<Option<(Tensor, Tensor)>>>>,
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device: Device,
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}
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impl Cache {
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fn new(use_kv_cache: bool, config: &Config, device: &Device) -> Self {
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Self {
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masks: Arc::new(Mutex::new(HashMap::new())),
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use_kv_cache,
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kvs: Arc::new(Mutex::new(vec![None; config.n_layer])),
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device: device.clone(),
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}
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}
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fn mask(&self, t: usize) -> Result<Tensor> {
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let mut masks = self.masks.lock().unwrap();
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if let Some(mask) = masks.get(&t) {
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Ok(mask.clone())
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} else {
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// TODO: If we support bool or u8 tensors, this would be better.
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let mask: Vec<_> = (0..t)
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.flat_map(|i| (0..t).map(move |j| u32::from(j > i)))
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.collect();
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let mask = Tensor::from_slice(&mask, (t, t), &self.device)?;
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masks.insert(t, mask.clone());
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Ok(mask)
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}
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}
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}
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struct CausalSelfAttention {
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c_attn: Linear,
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c_proj: Linear,
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n_head: usize,
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cache: Cache,
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}
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impl CausalSelfAttention {
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fn new(c_attn: Linear, c_proj: Linear, n_head: usize, cache: &Cache) -> Self {
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Self {
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c_attn,
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c_proj,
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n_head,
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cache: cache.clone(),
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}
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}
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fn apply_rotary_emb(&self, x: &Tensor, freqs_cis: &Tensor) -> Result<Tensor> {
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let mut dims = x.dims().to_vec();
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let fcis_dims = freqs_cis.dims();
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let freqs_cis = if dims[1] < fcis_dims[1] {
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freqs_cis.narrow(1, 0, dims[1])?
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} else {
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freqs_cis.clone()
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};
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let v = dims.pop().unwrap();
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dims.push(v / 2);
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dims.push(2);
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let x = x.reshape(dims)?;
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let re_x = x.narrow(D::Minus1, 0, 1)?;
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let im_x = x.narrow(D::Minus1, 1, 1)?;
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let re_f = freqs_cis
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.narrow(D::Minus1, 0, 1)?
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.broadcast_as(re_x.shape())?;
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let im_f = freqs_cis
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.narrow(D::Minus1, 1, 1)?
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.broadcast_as(im_x.shape())?;
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let re = ((&re_x * &re_f)? - (&im_x * &im_f)?)?;
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let im = ((&re_x * &im_f)? + (&im_x * &re_f)?)?;
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let rope = Tensor::cat(&[&re, &im], D::Minus1)?;
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let rope = rope.flatten_from(D::Minus2)?;
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Ok(rope)
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}
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fn forward(&self, x: &Tensor, freqs_cis: &Tensor, block_idx: usize) -> Result<Tensor> {
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let (t, c) = x.shape().r2()?;
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let qkv = self.c_attn.forward(x)?;
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let qkv = qkv.to_dtype(DType::F32)?;
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let n_embd = c;
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let q = qkv.narrow(1, 0, n_embd)?;
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let k = qkv.narrow(1, n_embd, n_embd)?;
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let v = qkv.narrow(1, 2 * n_embd, n_embd)?;
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let target_dim = [t, self.n_head, c / self.n_head];
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let k = k.reshape(target_dim.as_slice())?.transpose(0, 1)?;
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let q = q.reshape(target_dim.as_slice())?.transpose(0, 1)?;
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let mut v = v.reshape(target_dim.as_slice())?.transpose(0, 1)?;
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let q = self.apply_rotary_emb(&q, freqs_cis)?;
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let mut k = self.apply_rotary_emb(&k, freqs_cis)?;
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if self.cache.use_kv_cache {
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let mut cache = self.cache.kvs.lock().unwrap();
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if let Some((cache_k, cache_v)) = &cache[block_idx] {
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k = Tensor::cat(&[cache_k, &k], 1)?.contiguous()?;
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v = Tensor::cat(&[cache_v, &v], 1)?.contiguous()?;
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let k_seq_len = k.dims()[1];
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if k_seq_len > MAX_SEQ_LEN {
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k = k
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.narrow(1, k_seq_len - MAX_SEQ_LEN, MAX_SEQ_LEN)?
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.contiguous()?
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}
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let v_seq_len = v.dims()[1];
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if v_seq_len > 2 * MAX_SEQ_LEN {
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v = v
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.narrow(1, v_seq_len - MAX_SEQ_LEN, MAX_SEQ_LEN)?
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.contiguous()?
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}
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}
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cache[block_idx] = Some((k.clone(), v.clone()))
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}
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let att = (q.matmul(&k.t()?)? / (k.dim(D::Minus1)? as f64).sqrt())?;
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let mask = self.cache.mask(t)?.broadcast_as(att.shape())?;
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let att = masked_fill(&att, &mask, f32::NEG_INFINITY)?;
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let att = att.softmax(D::Minus1)?;
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// Convert to contiguous as matmul doesn't support strided vs for now.
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let y = att.matmul(&v.contiguous()?)?;
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let y = y.transpose(0, 1)?.reshape(&[t, c])?;
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let y = y.to_dtype(DTYPE)?;
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let y = self.c_proj.forward(&y)?;
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Ok(y)
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}
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}
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struct Block {
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rms_1: RmsNorm,
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attn: CausalSelfAttention,
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rms_2: RmsNorm,
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mlp: Mlp,
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}
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impl Block {
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fn new(rms_1: RmsNorm, attn: CausalSelfAttention, rms_2: RmsNorm, mlp: Mlp) -> Self {
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Self {
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rms_1,
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attn,
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rms_2,
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mlp,
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}
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}
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fn forward(&self, x: &Tensor, freqs_cis: &Tensor, block_idx: usize) -> Result<Tensor> {
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let x = (self
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.attn
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.forward(&self.rms_1.forward(x)?, freqs_cis, block_idx)?
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+ x)?;
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let x = (self.mlp.forward(&self.rms_2.forward(&x)?)? + x)?;
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Ok(x)
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}
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}
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struct Llama {
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wte: Embedding,
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blocks: Vec<Block>,
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ln_f: RmsNorm,
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lm_head: Linear,
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}
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impl Llama {
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fn new(wte: Embedding, blocks: Vec<Block>, ln_f: RmsNorm, lm_head: Linear) -> Self {
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Self {
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wte,
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blocks,
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ln_f,
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lm_head,
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}
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}
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fn forward(&self, x: &Tensor, freqs_cis: &Tensor) -> Result<Tensor> {
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// TODO: Support for mini-batches? (i.e. r2)
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let t = x.shape().r1()?;
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let mut x = self.wte.forward(x)?;
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for (block_idx, block) in self.blocks.iter().enumerate() {
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x = block.forward(&x, freqs_cis, block_idx)?;
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}
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let x = self.ln_f.forward(&x)?;
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let x = x.narrow(0, t - 1, 1)?;
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let logits = self.lm_head.forward(&x)?;
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let logits = logits.to_dtype(DType::F32)?;
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let (b, vocab_size) = logits.shape().r2()?;
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assert_eq!(b, 1);
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Ok(logits.reshape(vocab_size)?)
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}
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}
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fn precompute_freqs_cis(config: &Config, device: &Device) -> Result<Tensor> {
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let n_elem = config.n_embd / config.n_head;
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let theta: Vec<_> = (0..n_elem)
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@ -474,19 +142,15 @@ fn main() -> Result<()> {
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Device::new_cuda(0)?
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};
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let config = Config::config_7b();
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let cache = Cache::new(!args.no_kv_cache, &config, &device);
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let start = std::time::Instant::now();
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let cache = model::Cache::new(!args.no_kv_cache, &config, &device);
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let (llama, tokenizer_filename) = match args.npy {
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Some(npy) => {
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println!("building the model (NPY)");
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let weights = Llama::load_npy(&device, &npy, &cache, &config)?;
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let token_path = std::path::Path::new("llama-tokenizer.json").to_path_buf();
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(weights, token_path)
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Some(_) => {
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todo!("fix numpy handling if we continue supporting it")
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}
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None => {
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let api = Api::new()?;
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let repo = Repo::new("Narsil/amall-7b".to_string(), RepoType::Model);
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println!("building the model");
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println!("loading the model weights");
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let tokenizer_filename = api.get(&repo, "tokenizer.json")?;
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let mut filenames = vec![];
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for rfilename in [
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@ -497,14 +161,20 @@ fn main() -> Result<()> {
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filenames.push(filename);
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}
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println!("building the model (SF)");
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(
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Llama::load(&device, &filenames, &cache, &config)?,
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tokenizer_filename,
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)
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println!("building the model");
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let handles = filenames
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.iter()
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.map(|f| Ok(unsafe { candle::safetensors::MmapedFile::new(f.as_path())? }))
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.collect::<Result<Vec<_>>>()?;
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let tensors: Vec<_> = handles
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.iter()
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.map(|h| Ok(h.deserialize()?))
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.collect::<Result<Vec<_>>>()?;
|
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|
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let vb = VarBuilder::from_safetensors(tensors, DTYPE, &device);
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(Llama::load(vb, &cache, &config)?, tokenizer_filename)
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}
|
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};
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println!("Loaded in {:?}", start.elapsed());
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let tokenizer = Tokenizer::from_file(tokenizer_filename).map_err(E::msg)?;
|
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let prompt = args.prompt.as_ref().map_or(DEFAULT_PROMPT, |p| p.as_str());
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let mut tokens = tokenizer
|
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|
364
candle-examples/examples/llama/model.rs
Normal file
364
candle-examples/examples/llama/model.rs
Normal file
@ -0,0 +1,364 @@
|
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use candle::{DType, Device, Result, Tensor, D};
|
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use candle_nn::{Linear, VarBuilder};
|
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use std::collections::HashMap;
|
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use std::sync::{Arc, Mutex};
|
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|
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use super::MAX_SEQ_LEN;
|
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|
||||
pub struct Config {
|
||||
pub hidden_size: usize,
|
||||
pub intermediate_size: usize,
|
||||
pub vocab_size: usize,
|
||||
pub n_layer: usize,
|
||||
pub n_head: usize,
|
||||
pub n_embd: usize,
|
||||
}
|
||||
|
||||
impl Config {
|
||||
pub fn config_7b() -> Self {
|
||||
Self {
|
||||
hidden_size: 4096,
|
||||
intermediate_size: 11008,
|
||||
vocab_size: 32000,
|
||||
n_layer: 32,
|
||||
n_head: 32,
|
||||
n_embd: 4096,
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(Clone)]
|
||||
pub struct Cache {
|
||||
masks: Arc<Mutex<HashMap<usize, Tensor>>>,
|
||||
pub use_kv_cache: bool,
|
||||
#[allow(clippy::type_complexity)]
|
||||
kvs: Arc<Mutex<Vec<Option<(Tensor, Tensor)>>>>,
|
||||
device: Device,
|
||||
}
|
||||
|
||||
impl Cache {
|
||||
pub fn new(use_kv_cache: bool, config: &Config, device: &Device) -> Self {
|
||||
Self {
|
||||
masks: Arc::new(Mutex::new(HashMap::new())),
|
||||
use_kv_cache,
|
||||
kvs: Arc::new(Mutex::new(vec![None; config.n_layer])),
|
||||
device: device.clone(),
|
||||
}
|
||||
}
|
||||
|
||||
fn mask(&self, t: usize) -> Result<Tensor> {
|
||||
let mut masks = self.masks.lock().unwrap();
|
||||
if let Some(mask) = masks.get(&t) {
|
||||
Ok(mask.clone())
|
||||
} else {
|
||||
// TODO: If we support bool or u8 tensors, this would be better.
|
||||
let mask: Vec<_> = (0..t)
|
||||
.flat_map(|i| (0..t).map(move |j| u32::from(j > i)))
|
||||
.collect();
|
||||
let mask = Tensor::from_slice(&mask, (t, t), &self.device)?;
|
||||
masks.insert(t, mask.clone());
|
||||
Ok(mask)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn silu(xs: &Tensor) -> Result<Tensor> {
|
||||
xs / (xs.neg()?.exp()? + 1.0)?
|
||||
}
|
||||
|
||||
fn linear(size1: usize, size2: usize, vb: VarBuilder) -> Result<Linear> {
|
||||
let weight = vb.get((size2, size1), "weight")?;
|
||||
Ok(Linear::new(weight, None))
|
||||
}
|
||||
|
||||
struct Embedding {
|
||||
embeddings: Tensor,
|
||||
}
|
||||
|
||||
impl Embedding {
|
||||
fn new(embeddings: Tensor) -> Self {
|
||||
Self { embeddings }
|
||||
}
|
||||
|
||||
fn load(cfg: &Config, vb: VarBuilder) -> Result<Self> {
|
||||
let embeddings = vb.get((cfg.vocab_size, cfg.hidden_size), "weight")?;
|
||||
Ok(Self::new(embeddings))
|
||||
}
|
||||
|
||||
fn forward(&self, indexes: &Tensor) -> Result<Tensor> {
|
||||
Tensor::embedding(indexes, &self.embeddings)
|
||||
}
|
||||
}
|
||||
|
||||
struct RmsNorm {
|
||||
scale: Tensor,
|
||||
}
|
||||
|
||||
impl RmsNorm {
|
||||
fn load(size: usize, vb: VarBuilder) -> Result<Self> {
|
||||
let scale = vb.get(size, "weight")?;
|
||||
Ok(Self::new(scale))
|
||||
}
|
||||
|
||||
fn new(scale: Tensor) -> Self {
|
||||
Self { scale }
|
||||
}
|
||||
|
||||
fn forward(&self, x: &Tensor) -> Result<Tensor> {
|
||||
let in_dtype = x.dtype();
|
||||
// This is a no-op if x's dtype is already f32.
|
||||
let x = x.to_dtype(DType::F32)?;
|
||||
let (seq_len, hidden_size) = x.shape().r2()?;
|
||||
let norm_x = ((&x * &x)?.sum(&[1])? / hidden_size as f64)?;
|
||||
let norm_x = norm_x.broadcast_as((seq_len, hidden_size))?;
|
||||
let x_normed = (x / (norm_x + 1e-5)?.sqrt()?)?;
|
||||
let size = self.scale.shape().r1()?;
|
||||
let scale = self
|
||||
.scale
|
||||
.to_dtype(DType::F32)?
|
||||
.broadcast_as((seq_len, size))?;
|
||||
let x = (scale * x_normed)?;
|
||||
let x = x.to_dtype(in_dtype)?;
|
||||
Ok(x)
|
||||
}
|
||||
}
|
||||
|
||||
struct CausalSelfAttention {
|
||||
c_attn: Linear,
|
||||
c_proj: Linear,
|
||||
n_head: usize,
|
||||
cache: Cache,
|
||||
}
|
||||
|
||||
impl CausalSelfAttention {
|
||||
fn new(c_attn: Linear, c_proj: Linear, n_head: usize, cache: &Cache) -> Self {
|
||||
Self {
|
||||
c_attn,
|
||||
c_proj,
|
||||
n_head,
|
||||
cache: cache.clone(),
|
||||
}
|
||||
}
|
||||
|
||||
fn apply_rotary_emb(&self, x: &Tensor, freqs_cis: &Tensor) -> Result<Tensor> {
|
||||
let mut dims = x.dims().to_vec();
|
||||
let fcis_dims = freqs_cis.dims();
|
||||
let freqs_cis = if dims[1] < fcis_dims[1] {
|
||||
freqs_cis.narrow(1, 0, dims[1])?
|
||||
} else {
|
||||
freqs_cis.clone()
|
||||
};
|
||||
let v = dims.pop().unwrap();
|
||||
dims.push(v / 2);
|
||||
dims.push(2);
|
||||
let x = x.reshape(dims)?;
|
||||
let re_x = x.narrow(D::Minus1, 0, 1)?;
|
||||
let im_x = x.narrow(D::Minus1, 1, 1)?;
|
||||
let re_f = freqs_cis
|
||||
.narrow(D::Minus1, 0, 1)?
|
||||
.broadcast_as(re_x.shape())?;
|
||||
let im_f = freqs_cis
|
||||
.narrow(D::Minus1, 1, 1)?
|
||||
.broadcast_as(im_x.shape())?;
|
||||
let re = ((&re_x * &re_f)? - (&im_x * &im_f)?)?;
|
||||
let im = ((&re_x * &im_f)? + (&im_x * &re_f)?)?;
|
||||
let rope = Tensor::cat(&[&re, &im], D::Minus1)?;
|
||||
let rope = rope.flatten_from(D::Minus2)?;
|
||||
Ok(rope)
|
||||
}
|
||||
|
||||
fn forward(&self, x: &Tensor, freqs_cis: &Tensor, block_idx: usize) -> Result<Tensor> {
|
||||
let x_dtype = x.dtype();
|
||||
let (t, c) = x.shape().r2()?;
|
||||
let qkv = self.c_attn.forward(x)?;
|
||||
let qkv = qkv.to_dtype(DType::F32)?;
|
||||
let n_embd = c;
|
||||
let q = qkv.narrow(1, 0, n_embd)?;
|
||||
let k = qkv.narrow(1, n_embd, n_embd)?;
|
||||
let v = qkv.narrow(1, 2 * n_embd, n_embd)?;
|
||||
let target_dim = [t, self.n_head, c / self.n_head];
|
||||
let k = k.reshape(target_dim.as_slice())?.transpose(0, 1)?;
|
||||
let q = q.reshape(target_dim.as_slice())?.transpose(0, 1)?;
|
||||
let mut v = v.reshape(target_dim.as_slice())?.transpose(0, 1)?;
|
||||
let q = self.apply_rotary_emb(&q, freqs_cis)?;
|
||||
let mut k = self.apply_rotary_emb(&k, freqs_cis)?;
|
||||
|
||||
if self.cache.use_kv_cache {
|
||||
let mut cache = self.cache.kvs.lock().unwrap();
|
||||
if let Some((cache_k, cache_v)) = &cache[block_idx] {
|
||||
k = Tensor::cat(&[cache_k, &k], 1)?.contiguous()?;
|
||||
v = Tensor::cat(&[cache_v, &v], 1)?.contiguous()?;
|
||||
let k_seq_len = k.dims()[1];
|
||||
if k_seq_len > MAX_SEQ_LEN {
|
||||
k = k
|
||||
.narrow(1, k_seq_len - MAX_SEQ_LEN, MAX_SEQ_LEN)?
|
||||
.contiguous()?
|
||||
}
|
||||
let v_seq_len = v.dims()[1];
|
||||
if v_seq_len > 2 * MAX_SEQ_LEN {
|
||||
v = v
|
||||
.narrow(1, v_seq_len - MAX_SEQ_LEN, MAX_SEQ_LEN)?
|
||||
.contiguous()?
|
||||
}
|
||||
}
|
||||
cache[block_idx] = Some((k.clone(), v.clone()))
|
||||
}
|
||||
|
||||
let att = (q.matmul(&k.t()?)? / (k.dim(D::Minus1)? as f64).sqrt())?;
|
||||
let mask = self.cache.mask(t)?.broadcast_as(att.shape())?;
|
||||
let att = masked_fill(&att, &mask, f32::NEG_INFINITY)?;
|
||||
let att = att.softmax(D::Minus1)?;
|
||||
// Convert to contiguous as matmul doesn't support strided vs for now.
|
||||
let y = att.matmul(&v.contiguous()?)?;
|
||||
let y = y.transpose(0, 1)?.reshape(&[t, c])?;
|
||||
let y = y.to_dtype(x_dtype)?;
|
||||
let y = self.c_proj.forward(&y)?;
|
||||
Ok(y)
|
||||
}
|
||||
|
||||
fn load(vb: VarBuilder, cache: &Cache, cfg: &Config) -> Result<Self> {
|
||||
let size_in = cfg.hidden_size;
|
||||
let size = (cfg.hidden_size / cfg.n_head) * cfg.n_head;
|
||||
let q_proj = vb.get((size_in, size), "q_proj.weight")?;
|
||||
let k_proj = vb.get((size_in, size), "k_proj.weight")?;
|
||||
let v_proj = vb.get((size_in, size), "v_proj.weight")?;
|
||||
// Invert the transformation from:
|
||||
// https://github.com/huggingface/transformers/blob/2642d8d04b14c18199ebe7b35f976da02df61752/src/transformers/models/llama/convert_llama_weights_to_hf.py#L101
|
||||
let n_head = cfg.n_head;
|
||||
let q_proj = q_proj
|
||||
.reshape((n_head, 2, size / n_head / 2, size_in))?
|
||||
.transpose(1, 2)?
|
||||
.reshape((size_in, size))?;
|
||||
let k_proj = k_proj
|
||||
.reshape((n_head, 2, size / n_head / 2, size_in))?
|
||||
.transpose(1, 2)?
|
||||
.reshape((size_in, size))?;
|
||||
let attn_weight = Tensor::cat(&[q_proj, k_proj, v_proj], 0)?;
|
||||
let c_attn = Linear::new(attn_weight, None);
|
||||
let o_proj = linear(size, size_in, vb.pp("o_proj"))?;
|
||||
Ok(Self::new(c_attn, o_proj, cfg.n_head, cache))
|
||||
}
|
||||
}
|
||||
|
||||
fn masked_fill(on_false: &Tensor, mask: &Tensor, on_true: f32) -> Result<Tensor> {
|
||||
let shape = mask.shape();
|
||||
let on_true = Tensor::new(on_true, &on_false.device())?.broadcast_as(shape.dims())?;
|
||||
let m = mask.where_cond(&on_true, on_false)?;
|
||||
Ok(m)
|
||||
}
|
||||
|
||||
struct Mlp {
|
||||
c_fc1: Linear,
|
||||
c_fc2: Linear,
|
||||
c_proj: Linear,
|
||||
}
|
||||
|
||||
impl Mlp {
|
||||
fn new(c_fc1: Linear, c_fc2: Linear, c_proj: Linear) -> Self {
|
||||
Self {
|
||||
c_fc1,
|
||||
c_fc2,
|
||||
c_proj,
|
||||
}
|
||||
}
|
||||
|
||||
fn forward(&self, x: &Tensor) -> Result<Tensor> {
|
||||
let x = (silu(&self.c_fc1.forward(x)?)? * self.c_fc2.forward(x)?)?;
|
||||
self.c_proj.forward(&x)
|
||||
}
|
||||
|
||||
fn load(vb: VarBuilder, cfg: &Config) -> Result<Self> {
|
||||
let h_size = cfg.hidden_size;
|
||||
let i_size = cfg.intermediate_size;
|
||||
let c_fc1 = linear(h_size, i_size, vb.pp("gate_proj"))?;
|
||||
let c_fc2 = linear(h_size, i_size, vb.pp("up_proj"))?;
|
||||
let c_proj = linear(i_size, h_size, vb.pp("down_proj"))?;
|
||||
Ok(Self::new(c_fc1, c_fc2, c_proj))
|
||||
}
|
||||
}
|
||||
|
||||
struct Block {
|
||||
rms_1: RmsNorm,
|
||||
attn: CausalSelfAttention,
|
||||
rms_2: RmsNorm,
|
||||
mlp: Mlp,
|
||||
}
|
||||
|
||||
impl Block {
|
||||
fn new(rms_1: RmsNorm, attn: CausalSelfAttention, rms_2: RmsNorm, mlp: Mlp) -> Self {
|
||||
Self {
|
||||
rms_1,
|
||||
attn,
|
||||
rms_2,
|
||||
mlp,
|
||||
}
|
||||
}
|
||||
|
||||
fn forward(&self, x: &Tensor, freqs_cis: &Tensor, block_idx: usize) -> Result<Tensor> {
|
||||
let x = (self
|
||||
.attn
|
||||
.forward(&self.rms_1.forward(x)?, freqs_cis, block_idx)?
|
||||
+ x)?;
|
||||
let x = (self.mlp.forward(&self.rms_2.forward(&x)?)? + x)?;
|
||||
Ok(x)
|
||||
}
|
||||
|
||||
fn load(vb: VarBuilder, cache: &Cache, cfg: &Config) -> Result<Self> {
|
||||
let attn = CausalSelfAttention::load(vb.pp("self_attn"), cache, cfg)?;
|
||||
let mlp = Mlp::load(vb.pp("mlp"), cfg)?;
|
||||
let input_layernorm = RmsNorm::load(cfg.hidden_size, vb.pp("input_layernorm"))?;
|
||||
let post_attention_layernorm =
|
||||
RmsNorm::load(cfg.hidden_size, vb.pp("post_attention_layernorm"))?;
|
||||
Ok(Self::new(
|
||||
input_layernorm,
|
||||
attn,
|
||||
post_attention_layernorm,
|
||||
mlp,
|
||||
))
|
||||
}
|
||||
}
|
||||
|
||||
pub struct Llama {
|
||||
wte: Embedding,
|
||||
blocks: Vec<Block>,
|
||||
ln_f: RmsNorm,
|
||||
lm_head: Linear,
|
||||
}
|
||||
|
||||
impl Llama {
|
||||
fn new(wte: Embedding, blocks: Vec<Block>, ln_f: RmsNorm, lm_head: Linear) -> Self {
|
||||
Self {
|
||||
wte,
|
||||
blocks,
|
||||
ln_f,
|
||||
lm_head,
|
||||
}
|
||||
}
|
||||
|
||||
pub fn forward(&self, x: &Tensor, freqs_cis: &Tensor) -> Result<Tensor> {
|
||||
// TODO: Support for mini-batches? (i.e. r2)
|
||||
let t = x.shape().r1()?;
|
||||
let mut x = self.wte.forward(x)?;
|
||||
for (block_idx, block) in self.blocks.iter().enumerate() {
|
||||
x = block.forward(&x, freqs_cis, block_idx)?;
|
||||
}
|
||||
let x = self.ln_f.forward(&x)?;
|
||||
let x = x.narrow(0, t - 1, 1)?;
|
||||
let logits = self.lm_head.forward(&x)?;
|
||||
let logits = logits.to_dtype(DType::F32)?;
|
||||
let (b, vocab_size) = logits.shape().r2()?;
|
||||
assert_eq!(b, 1);
|
||||
logits.reshape(vocab_size)
|
||||
}
|
||||
|
||||
pub fn load(vb: VarBuilder, cache: &Cache, cfg: &Config) -> Result<Self> {
|
||||
let wte = Embedding::load(cfg, vb.pp("model.embed_tokens"))?;
|
||||
let lm_head = linear(cfg.hidden_size, cfg.vocab_size, vb.pp("lm_head"))?;
|
||||
let norm = RmsNorm::load(cfg.hidden_size, vb.pp("model.norm"))?;
|
||||
let blocks: Vec<_> = (0..cfg.n_layer)
|
||||
.map(|i| Block::load(vb.pp(&format!("model.layers.{i}")), cache, cfg).unwrap())
|
||||
.collect();
|
||||
|
||||
Ok(Self::new(wte, blocks, norm, lm_head))
|
||||
}
|
||||
}
|
@ -1,137 +0,0 @@
|
||||
use super::*;
|
||||
use candle::{Device, Result, Tensor};
|
||||
use std::collections::HashMap;
|
||||
use std::sync::{Arc, Mutex};
|
||||
|
||||
#[derive(Clone)]
|
||||
pub struct VarBuilder {
|
||||
path: Vec<String>,
|
||||
default_device: Device,
|
||||
tensors: Arc<Mutex<HashMap<String, Tensor>>>,
|
||||
}
|
||||
|
||||
impl VarBuilder {
|
||||
pub fn new(device: &Device, tensors: HashMap<String, Tensor>) -> Self {
|
||||
Self {
|
||||
path: vec![],
|
||||
tensors: Arc::new(Mutex::new(tensors)),
|
||||
default_device: device.clone(),
|
||||
}
|
||||
}
|
||||
|
||||
pub fn get_and_remove(&self, s: &str) -> Result<Tensor> {
|
||||
let path = format!("{}.{s}", self.path.join("."));
|
||||
let mut tensors = self.tensors.as_ref().lock().unwrap();
|
||||
let parameter = match tensors.remove(&path) {
|
||||
Some(tensor) => tensor.to_device(&self.default_device)?,
|
||||
None => panic!("cannot find tensor for {path}"),
|
||||
};
|
||||
Ok(parameter)
|
||||
}
|
||||
}
|
||||
|
||||
impl<S: ToString> std::ops::Div<S> for &VarBuilder {
|
||||
type Output = VarBuilder;
|
||||
|
||||
fn div(self, rhs: S) -> VarBuilder {
|
||||
let mut path = self.path.clone();
|
||||
path.push(rhs.to_string());
|
||||
VarBuilder {
|
||||
path,
|
||||
default_device: self.default_device.clone(),
|
||||
tensors: self.tensors.clone(),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<S: ToString> std::ops::Div<S> for VarBuilder {
|
||||
type Output = VarBuilder;
|
||||
|
||||
fn div(self, rhs: S) -> VarBuilder {
|
||||
&self / rhs
|
||||
}
|
||||
}
|
||||
|
||||
impl Embedding {
|
||||
fn load_npy(vb: VarBuilder) -> Result<Self> {
|
||||
let embeddings = vb.get_and_remove("weight")?.to_dtype(DTYPE)?;
|
||||
Ok(Self { embeddings })
|
||||
}
|
||||
}
|
||||
|
||||
impl Linear {
|
||||
fn load_npy(vb: VarBuilder) -> Result<Self> {
|
||||
let weight = vb.get_and_remove("weight")?.to_dtype(DTYPE)?.t()?;
|
||||
Ok(Self { weight })
|
||||
}
|
||||
}
|
||||
|
||||
impl RmsNorm {
|
||||
fn load_npy(vb: VarBuilder) -> Result<Self> {
|
||||
let scale = vb.get_and_remove("scale")?.to_dtype(DTYPE)?;
|
||||
Ok(Self::new(scale))
|
||||
}
|
||||
}
|
||||
|
||||
impl CausalSelfAttention {
|
||||
fn load_npy(vb: VarBuilder, cache: &Cache, config: &Config) -> Result<Self> {
|
||||
let c_attn = Linear::load_npy(&vb / "c_attn")?;
|
||||
let c_proj = Linear::load_npy(&vb / "c_proj")?;
|
||||
Ok(Self::new(c_attn, c_proj, config.n_head, cache))
|
||||
}
|
||||
}
|
||||
|
||||
impl Mlp {
|
||||
fn load_npy(vb: VarBuilder) -> Result<Self> {
|
||||
let c_fc1 = Linear::load_npy(&vb / "c_fc1")?;
|
||||
let c_fc2 = Linear::load_npy(&vb / "c_fc2")?;
|
||||
let c_proj = Linear::load_npy(&vb / "c_proj")?;
|
||||
Ok(Self::new(c_fc1, c_fc2, c_proj))
|
||||
}
|
||||
}
|
||||
|
||||
impl Block {
|
||||
fn load_npy(vb: VarBuilder, cache: &Cache, config: &Config) -> Result<Self> {
|
||||
let attn = CausalSelfAttention::load_npy(&vb / "attn", cache, config)?;
|
||||
let mlp = Mlp::load_npy(&vb / "mlp")?;
|
||||
let input_layernorm = RmsNorm::load_npy(&vb / "rms_1")?;
|
||||
let post_attention_layernorm = RmsNorm::load_npy(&vb / "rms_2")?;
|
||||
Ok(Self::new(
|
||||
input_layernorm,
|
||||
attn,
|
||||
post_attention_layernorm,
|
||||
mlp,
|
||||
))
|
||||
}
|
||||
}
|
||||
|
||||
impl Llama {
|
||||
pub fn load_npy(
|
||||
device: &Device,
|
||||
filename: &str,
|
||||
cache: &Cache,
|
||||
config: &Config,
|
||||
) -> anyhow::Result<Self> {
|
||||
let weight_path = std::path::Path::new(filename);
|
||||
let weights = if weight_path.exists() {
|
||||
println!("loading weights from {weight_path:?}");
|
||||
let start_load = std::time::Instant::now();
|
||||
let tensors = Tensor::read_npz(weight_path)?;
|
||||
println!("loaded weights in {:?}", start_load.elapsed());
|
||||
let tensors: std::collections::HashMap<String, Tensor> = tensors.into_iter().collect();
|
||||
tensors
|
||||
} else {
|
||||
anyhow::bail!("cannot find {weight_path:?}")
|
||||
};
|
||||
let vb = VarBuilder::new(device, weights);
|
||||
|
||||
let wte = Embedding::load_npy(&vb / "transformer" / "wte")?;
|
||||
let lm_head = Linear::load_npy(&vb / "lm_head")?;
|
||||
let norm = RmsNorm::load_npy(&vb / "transformer" / "ln_f")?;
|
||||
let blocks: Vec<_> = (0..config.n_layer)
|
||||
.map(|i| Block::load_npy(&vb / "transformer" / "h" / i, cache, config).unwrap())
|
||||
.collect();
|
||||
|
||||
Ok(Self::new(wte, blocks, norm, lm_head))
|
||||
}
|
||||
}
|
@ -1,127 +0,0 @@
|
||||
use super::*;
|
||||
use candle::{safetensors::SafeTensors, Device, Result, Tensor};
|
||||
use std::path::PathBuf;
|
||||
|
||||
pub struct VarBuilder<'a> {
|
||||
routing: HashMap<String, usize>,
|
||||
safetensors: Vec<SafeTensors<'a>>,
|
||||
device: Device,
|
||||
}
|
||||
|
||||
impl<'a> VarBuilder<'a> {
|
||||
pub fn new(safetensors: Vec<SafeTensors<'a>>, device: Device) -> Self {
|
||||
let mut routing = HashMap::new();
|
||||
for (index, sf) in safetensors.iter().enumerate() {
|
||||
for k in sf.names() {
|
||||
routing.insert(k.to_string(), index);
|
||||
}
|
||||
}
|
||||
|
||||
Self {
|
||||
safetensors,
|
||||
device,
|
||||
routing,
|
||||
}
|
||||
}
|
||||
|
||||
pub fn get(&self, tensor_name: &str) -> Result<Tensor> {
|
||||
// Unwrap or 0 just to let the proper error flow.
|
||||
let index = self.routing.get(tensor_name).unwrap_or(&0);
|
||||
self.safetensors[*index]
|
||||
.tensor(tensor_name, &self.device)?
|
||||
.to_dtype(DTYPE)
|
||||
}
|
||||
}
|
||||
|
||||
impl Linear {
|
||||
fn load(prefix: &str, vb: &VarBuilder) -> Result<Self> {
|
||||
let weight = vb.get(&format!("{prefix}.weight"))?;
|
||||
Ok(Self::new(weight))
|
||||
}
|
||||
|
||||
fn load_multi(prefixes: &[&str], vb: &VarBuilder) -> Result<Self> {
|
||||
let weights: Vec<_> = prefixes
|
||||
.iter()
|
||||
.map(|p| vb.get(&format!("{p}.weight")).unwrap())
|
||||
.collect();
|
||||
let weight = Tensor::cat(&weights, 0)?;
|
||||
Ok(Self::new(weight))
|
||||
}
|
||||
}
|
||||
|
||||
impl RmsNorm {
|
||||
fn load(prefix: &str, vb: &VarBuilder) -> Result<Self> {
|
||||
let scale = vb.get(&format!("{prefix}.weight"))?;
|
||||
Ok(Self::new(scale))
|
||||
}
|
||||
}
|
||||
|
||||
impl CausalSelfAttention {
|
||||
fn load(prefix: &str, vb: &VarBuilder, cache: &Cache, config: &Config) -> Result<Self> {
|
||||
let c_attn = Linear::load_multi(
|
||||
&[
|
||||
&format!("{prefix}.q_proj"),
|
||||
&format!("{prefix}.k_proj"),
|
||||
&format!("{prefix}.v_proj"),
|
||||
],
|
||||
vb,
|
||||
)?;
|
||||
let o_proj = Linear::load(&format!("{prefix}.o_proj"), vb)?;
|
||||
Ok(Self::new(c_attn, o_proj, config.n_head, cache))
|
||||
}
|
||||
}
|
||||
|
||||
impl Mlp {
|
||||
fn load(prefix: &str, vb: &VarBuilder) -> Result<Self> {
|
||||
let c_fc1 = Linear::load(&format!("{prefix}.gate_proj"), vb)?;
|
||||
let c_fc2 = Linear::load(&format!("{prefix}.up_proj"), vb)?;
|
||||
let c_proj = Linear::load(&format!("{prefix}.down_proj"), vb)?;
|
||||
Ok(Self::new(c_fc1, c_fc2, c_proj))
|
||||
}
|
||||
}
|
||||
|
||||
impl Block {
|
||||
fn load(prefix: &str, vb: &VarBuilder, cache: &Cache, config: &Config) -> Result<Self> {
|
||||
let attn = CausalSelfAttention::load(&format!("{prefix}.self_attn"), vb, cache, config)?;
|
||||
let mlp = Mlp::load(&format!("{prefix}.mlp"), vb)?;
|
||||
let input_layernorm = RmsNorm::load(&format!("{prefix}.input_layernorm"), vb)?;
|
||||
let post_attention_layernorm =
|
||||
RmsNorm::load(&format!("{prefix}.post_attention_layernorm"), vb)?;
|
||||
Ok(Self::new(
|
||||
input_layernorm,
|
||||
attn,
|
||||
post_attention_layernorm,
|
||||
mlp,
|
||||
))
|
||||
}
|
||||
}
|
||||
|
||||
impl Llama {
|
||||
pub fn load(
|
||||
device: &Device,
|
||||
filenames: &[PathBuf],
|
||||
cache: &Cache,
|
||||
config: &Config,
|
||||
) -> Result<Self> {
|
||||
let handles: Vec<_> = filenames
|
||||
.iter()
|
||||
.map(|f| unsafe { candle::safetensors::MmapedFile::new(f) })
|
||||
.collect::<Result<Vec<_>>>()?;
|
||||
let tensors: Vec<_> = handles
|
||||
.iter()
|
||||
.map(|h| h.deserialize())
|
||||
.collect::<Result<Vec<_>>>()?;
|
||||
|
||||
let vb = VarBuilder::new(tensors, device.clone());
|
||||
|
||||
let embedding = vb.get("model.embed_tokens.weight")?;
|
||||
let wte = Embedding::new(embedding);
|
||||
let lm_head = Linear::load("lm_head", &vb)?;
|
||||
let norm = RmsNorm::load("model.norm", &vb)?;
|
||||
let blocks: Vec<_> = (0..config.n_layer)
|
||||
.map(|i| Block::load(&format!("model.layers.{i}"), &vb, cache, config).unwrap())
|
||||
.collect();
|
||||
|
||||
Ok(Self::new(wte, blocks, norm, lm_head))
|
||||
}
|
||||
}
|
Reference in New Issue
Block a user