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aha/src/models/common/mod.rs
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use anyhow::Result;
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use candle_core::{D, Tensor};
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use candle_nn::{
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Activation, BatchNorm, BatchNormConfig, Conv1d, Conv1dConfig, Conv2d, Conv2dConfig, Embedding,
LayerNorm, LayerNormConfig, Linear, Module, RmsNorm, VarBuilder, batch_norm, conv1d,
conv1d_no_bias, conv2d, conv2d_no_bias, embedding, layer_norm, linear, linear_no_bias,
rms_norm,
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};
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use crate::{
position_embed::rope::{RoPE, apply_rotary_pos_emb},
utils::tensor_utils::{prepare_causal_attention_mask, repeat_kv},
};
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#[derive(Debug, Clone)]
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pub struct GateUpDownMLP {
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gate_proj: Linear,
up_proj: Linear,
down_proj: Linear,
act_fn: Activation,
}
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impl GateUpDownMLP {
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pub fn new(
vb: VarBuilder,
hidden_size: usize,
intermediate_size: usize,
act_fn: Activation,
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bias: bool,
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) -> Result<Self> {
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let (gate_proj, up_proj, down_proj) = if bias {
(
linear(hidden_size, intermediate_size, vb.pp("gate_proj"))?,
linear(hidden_size, intermediate_size, vb.pp("up_proj"))?,
linear(intermediate_size, hidden_size, vb.pp("down_proj"))?,
)
} else {
(
linear_no_bias(hidden_size, intermediate_size, vb.pp("gate_proj"))?,
linear_no_bias(hidden_size, intermediate_size, vb.pp("up_proj"))?,
linear_no_bias(intermediate_size, hidden_size, vb.pp("down_proj"))?,
)
};
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Ok(Self {
gate_proj,
up_proj,
down_proj,
act_fn,
})
}
}
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impl Module for GateUpDownMLP {
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fn forward(&self, xs: &Tensor) -> candle_core::Result<Tensor> {
let lhs = xs.apply(&self.gate_proj)?.apply(&self.act_fn)?;
let rhs = xs.apply(&self.up_proj)?;
(lhs * rhs)?.apply(&self.down_proj)
}
}
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pub struct TwoLinearMLP {
linear1: Linear,
linear2: Linear,
act: Activation,
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}
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impl TwoLinearMLP {
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pub fn new(
vb: VarBuilder,
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// embedding_dim: usize,
// mlp_dim: usize,
in_dim: usize,
middle_dim: usize,
out_dim: usize,
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act: Activation,
bias: bool,
linear1_pp_name: &str,
linear2_pp_name: &str,
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) -> Result<Self> {
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let (linear1, linear2) = if bias {
(
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linear(in_dim, middle_dim, vb.pp(linear1_pp_name))?,
linear(middle_dim, out_dim, vb.pp(linear2_pp_name))?,
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)
} else {
(
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linear_no_bias(in_dim, middle_dim, vb.pp(linear1_pp_name))?,
linear_no_bias(middle_dim, out_dim, vb.pp(linear2_pp_name))?,
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)
};
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Ok(Self {
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linear1,
linear2,
act,
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})
}
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pub fn forward(&self, xs: &Tensor) -> Result<Tensor> {
let xs = xs
.apply(&self.linear1)?
.apply(&self.act)?
.apply(&self.linear2)?;
Ok(xs)
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}
}
#[derive(Debug, Clone)]
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// pub struct AttentionNobias {
pub struct NaiveAttention {
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q_proj: Linear,
k_proj: Linear,
v_proj: Linear,
o_proj: Linear,
num_heads: usize,
num_kv_heads: usize,
num_kv_groups: usize,
head_dim: usize,
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middle_size: usize,
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kv_cache: Option<(Tensor, Tensor)>,
}
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impl NaiveAttention {
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pub fn new(
vb: VarBuilder,
hidden_size: usize,
num_attention_heads: usize,
num_key_value_heads: usize,
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head_dim: Option<usize>,
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bias: bool,
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o_proj_pp_name: Option<&str>,
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) -> Result<Self> {
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let num_kv_groups = num_attention_heads / num_key_value_heads;
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let head_dim = match head_dim {
None => hidden_size / num_attention_heads,
Some(dim) => dim,
};
let o_proj_pp_name = o_proj_pp_name.unwrap_or("o_proj");
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let (q_proj, k_proj, v_proj, o_proj) = if bias {
(
linear(hidden_size, num_attention_heads * head_dim, vb.pp("q_proj"))?,
linear(hidden_size, num_key_value_heads * head_dim, vb.pp("k_proj"))?,
linear(hidden_size, num_key_value_heads * head_dim, vb.pp("v_proj"))?,
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linear(
num_attention_heads * head_dim,
hidden_size,
vb.pp(o_proj_pp_name),
)?,
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)
} else {
(
linear_no_bias(hidden_size, num_attention_heads * head_dim, vb.pp("q_proj"))?,
linear_no_bias(hidden_size, num_key_value_heads * head_dim, vb.pp("k_proj"))?,
linear_no_bias(hidden_size, num_key_value_heads * head_dim, vb.pp("v_proj"))?,
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linear_no_bias(
num_attention_heads * head_dim,
hidden_size,
vb.pp(o_proj_pp_name),
)?,
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)
};
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Ok(Self {
q_proj,
k_proj,
v_proj,
o_proj,
num_heads: num_attention_heads,
num_kv_heads: num_key_value_heads,
num_kv_groups,
head_dim,
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middle_size: num_attention_heads * head_dim,
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kv_cache: None,
})
}
pub fn forward(
&self,
xs: &Tensor,
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cos: Option<&Tensor>,
sin: Option<&Tensor>,
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attention_mask: Option<&Tensor>,
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tof32: bool,
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) -> Result<Tensor> {
let (b_sz, q_len, _) = xs.dims3()?;
let query_states = self.q_proj.forward(xs)?;
let key_states = self.k_proj.forward(xs)?;
let value_states = self.v_proj.forward(xs)?;
let query_states = query_states
.reshape((b_sz, q_len, self.num_heads, self.head_dim))?
.transpose(1, 2)?;
let key_states = key_states
.reshape((b_sz, q_len, self.num_kv_heads, self.head_dim))?
.transpose(1, 2)?;
let value_states = value_states
.reshape((b_sz, q_len, self.num_kv_heads, self.head_dim))?
.transpose(1, 2)?;
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let (query_states, key_states) = if let Some(cos) = cos
&& let Some(sin) = sin
{
apply_rotary_pos_emb(&query_states, &key_states, cos, sin, tof32)?
} else {
(query_states, key_states)
};
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let scale = 1f64 / f64::sqrt(self.head_dim as f64);
let attn_output = eager_attention_forward(
&query_states,
&key_states,
&value_states,
Some(self.num_kv_groups),
attention_mask,
scale,
)?;
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let attn_output = attn_output.reshape((b_sz, q_len, self.middle_size))?;
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let attn_output = attn_output.apply(&self.o_proj)?;
Ok(attn_output)
}
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pub fn forward_with_cache(
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&mut self,
xs: &Tensor,
cos: &Tensor,
sin: &Tensor,
attention_mask: Option<&Tensor>,
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tof32: bool,
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) -> Result<Tensor> {
let (b_sz, q_len, _) = xs.dims3()?;
let query_states = self.q_proj.forward(xs)?;
let key_states = self.k_proj.forward(xs)?;
let value_states = self.v_proj.forward(xs)?;
let query_states = query_states
.reshape((b_sz, q_len, self.num_heads, self.head_dim))?
.transpose(1, 2)?;
let key_states = key_states
.reshape((b_sz, q_len, self.num_kv_heads, self.head_dim))?
.transpose(1, 2)?;
let value_states = value_states
.reshape((b_sz, q_len, self.num_kv_heads, self.head_dim))?
.transpose(1, 2)?;
let (query_states, key_states) =
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apply_rotary_pos_emb(&query_states, &key_states, cos, sin, tof32)?;
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let (key_states, value_states) = match &self.kv_cache {
None => (key_states, value_states),
Some((prev_k, prev_v)) => {
let key_states = Tensor::cat(&[prev_k, &key_states], 2)?;
let value_states = Tensor::cat(&[prev_v, &value_states], 2)?;
(key_states, value_states)
}
};
self.kv_cache = Some((key_states.clone(), value_states.clone()));
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let scale = 1f64 / f64::sqrt(self.head_dim as f64);
let attn_output = eager_attention_forward(
&query_states,
&key_states,
&value_states,
Some(self.num_kv_groups),
attention_mask,
scale,
)?;
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let attn_output = attn_output.reshape((b_sz, q_len, self.middle_size))?;
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let attn_output = attn_output.apply(&self.o_proj)?;
Ok(attn_output)
}
pub fn clear_kv_cache(&mut self) {
self.kv_cache = None
}
}
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pub struct NaiveAttnTwoLinearMLPBlock {
self_attn: NaiveAttention,
mlp: TwoLinearMLP,
input_layernorm: LayerNorm,
post_attention_layernorm: LayerNorm,
}
impl NaiveAttnTwoLinearMLPBlock {
pub fn new(
vb: VarBuilder,
hidden_size: usize,
num_attention_heads: usize,
num_key_value_heads: Option<usize>,
head_dim: Option<usize>,
attn_bias: bool,
attn_pp_name: &str,
o_proj_pp_name: Option<&str>,
intermediate_size: usize,
hidden_act: Activation,
mlp_bias: bool,
mlp_pp_name: &str,
linear1_pp_name: &str,
linear2_pp_name: &str,
norm_eps: f64,
input_norm_pp_name: &str,
post_norm_pp_name: &str,
) -> Result<Self> {
let num_key_value_heads = match num_key_value_heads {
Some(heads) => heads,
None => num_attention_heads,
};
let self_attn = NaiveAttention::new(
vb.pp(attn_pp_name),
hidden_size,
num_attention_heads,
num_key_value_heads,
head_dim,
attn_bias,
o_proj_pp_name,
)?;
let mlp = TwoLinearMLP::new(
vb.pp(mlp_pp_name),
hidden_size,
intermediate_size,
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hidden_size,
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hidden_act,
mlp_bias,
linear1_pp_name,
linear2_pp_name,
)?;
let input_layernorm = get_layer_norm(vb.pp(input_norm_pp_name), norm_eps, hidden_size)?;
let post_attention_layernorm =
get_layer_norm(vb.pp(post_norm_pp_name), norm_eps, hidden_size)?;
Ok(Self {
self_attn,
mlp,
input_layernorm,
post_attention_layernorm,
})
}
pub fn forward(
&self,
xs: &Tensor,
cos: Option<&Tensor>,
sin: Option<&Tensor>,
attention_mask: Option<&Tensor>,
tof32: bool,
) -> Result<Tensor> {
let residual = xs.clone();
let xs = self.input_layernorm.forward(xs)?;
let xs = self
.self_attn
.forward(&xs, cos, sin, attention_mask, tof32)?;
let residual = residual.add(&xs)?;
let xs = self.post_attention_layernorm.forward(&residual)?;
let xs = self.mlp.forward(&xs)?;
let xs = residual.add(&xs)?;
Ok(xs)
}
}
pub struct NaiveAttnGateUpDownMLPBlock {
self_attn: NaiveAttention,
mlp: GateUpDownMLP,
input_layernorm: RmsNorm,
post_attention_layernorm: RmsNorm,
}
impl NaiveAttnGateUpDownMLPBlock {
pub fn new(
vb: VarBuilder,
hidden_size: usize,
num_attention_heads: usize,
num_key_value_heads: Option<usize>,
head_dim: Option<usize>,
attn_bias: bool,
attn_pp_name: &str,
o_proj_pp_name: Option<&str>,
intermediate_size: usize,
hidden_act: Activation,
mlp_bias: bool,
mlp_pp_name: &str,
norm_eps: f64,
input_norm_pp_name: &str,
post_norm_pp_name: &str,
) -> Result<Self> {
let num_key_value_heads = match num_key_value_heads {
Some(heads) => heads,
None => num_attention_heads,
};
let self_attn = NaiveAttention::new(
vb.pp(attn_pp_name),
hidden_size,
num_attention_heads,
num_key_value_heads,
head_dim,
attn_bias,
o_proj_pp_name,
)?;
let mlp = GateUpDownMLP::new(
vb.pp(mlp_pp_name),
hidden_size,
intermediate_size,
hidden_act,
mlp_bias,
)?;
let input_layernorm = rms_norm(hidden_size, norm_eps, vb.pp(input_norm_pp_name))?;
let post_attention_layernorm = rms_norm(hidden_size, norm_eps, vb.pp(post_norm_pp_name))?;
Ok(Self {
self_attn,
mlp,
input_layernorm,
post_attention_layernorm,
})
}
pub fn forward(
&mut self,
xs: &Tensor,
cos: &Tensor,
sin: &Tensor,
attention_mask: Option<&Tensor>,
) -> Result<Tensor> {
let residual = xs.clone();
let xs = self.input_layernorm.forward(xs)?;
let xs = self
.self_attn
.forward_with_cache(&xs, cos, sin, attention_mask, false)?;
let residual = residual.add(&xs)?;
let xs = self.post_attention_layernorm.forward(&residual)?;
let xs = self.mlp.forward(&xs)?;
let xs = residual.add(&xs)?;
Ok(xs)
}
pub fn clear_kv_cache(&mut self) {
self.self_attn.clear_kv_cache()
}
}
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pub fn eager_attention_forward(
query_states: &Tensor,
key_states: &Tensor,
value_states: &Tensor,
num_key_value_groups: Option<usize>,
attention_mask: Option<&Tensor>,
scaling: f64,
) -> Result<Tensor> {
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// input q shape:(b, num_head, seq_len, dim)
// input k/v shape:(b, num_kv_head, seq_len, dim)
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let key_states = match num_key_value_groups {
Some(g) => repeat_kv(key_states.clone(), g)?.contiguous()?,
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None => key_states.clone(),
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};
let value_states = match num_key_value_groups {
Some(g) => repeat_kv(value_states.clone(), g)?.contiguous()?,
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None => value_states.clone(),
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};
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let query_states = query_states.contiguous()?;
let key_states = key_states.contiguous()?;
let value_states = value_states.contiguous()?;
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let attn_output = {
#[cfg(not(feature = "flash-attn"))]
{
let attn_weights = query_states.matmul(&key_states.transpose(D::Minus2, D::Minus1)?)?;
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let attn_weights = (attn_weights * scaling)?;
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let attn_weights = match attention_mask {
None => attn_weights,
Some(mask) => attn_weights.broadcast_add(&mask.to_dtype(attn_weights.dtype())?)?,
};
let attn_weights = candle_nn::ops::softmax_last_dim(&attn_weights)?;
attn_weights.matmul(&value_states)?
}
#[cfg(feature = "flash-attn")]
{
// use flash-attn,
// flash-attn shape: (bs, seq_len, num_head, head_dim)
let query_states = query_states.transpose(1, 2)?;
let key_states = key_states.transpose(1, 2)?;
let value_states = value_states.transpose(1, 2)?;
let attn_output = candle_flash_attn::flash_attn(
&query_states,
&key_states,
&value_states,
scaling as f32,
attention_mask.is_some(),
)?
.transpose(1, 2)?;
attn_output
}
};
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//(b, n_head, seq_len, dim) -> (b, seq_len, n_head, dim)
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let attn_output = attn_output.transpose(1, 2)?.contiguous()?;
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Ok(attn_output)
}
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pub fn get_conv2d(
vb: VarBuilder,
in_c: usize,
out_c: usize,
kernel_size: usize,
padding: usize,
stride: usize,
dilation: usize,
groups: usize,
bias: bool,
) -> Result<Conv2d> {
let cfg = Conv2dConfig {
padding,
stride,
dilation,
groups,
cudnn_fwd_algo: None,
};
let conv2d = if bias {
conv2d(in_c, out_c, kernel_size, cfg, vb)?
} else {
conv2d_no_bias(in_c, out_c, kernel_size, cfg, vb)?
};
Ok(conv2d)
}
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pub fn get_conv1d(
vb: VarBuilder,
in_c: usize,
out_c: usize,
kernel_size: usize,
padding: usize,
stride: usize,
dilation: usize,
groups: usize,
bias: bool,
) -> Result<Conv1d> {
let cfg = Conv1dConfig {
padding,
stride,
dilation,
groups,
cudnn_fwd_algo: None,
};
let conv1d = if bias {
conv1d(in_c, out_c, kernel_size, cfg, vb)?
} else {
conv1d_no_bias(in_c, out_c, kernel_size, cfg, vb)?
};
Ok(conv1d)
}
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pub fn get_layer_norm(vb: VarBuilder, eps: f64, dim: usize) -> Result<LayerNorm> {
let ln_config = LayerNormConfig {
eps,
remove_mean: true, // true for layernorm, false for RMSNorm
affine: true, // true for with bias, false for without bias
};
let norm = layer_norm(dim, ln_config, vb)?;
Ok(norm)
}
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pub fn get_batch_norm(vb: VarBuilder, eps: f64, dim: usize) -> Result<BatchNorm> {
let bn_config = BatchNormConfig {
eps,
remove_mean: true,
affine: true,
momentum: 0.1,
};
let norm = batch_norm(dim, bn_config, vb)?;
Ok(norm)
}
pub fn deform_conv2d_kernel(
input: &Tensor,
weight: &Tensor,
bias: Option<&Tensor>,
offset: &Tensor,
mask: Option<&Tensor>,
stride: usize,
padding: usize,
) -> Result<Tensor> {
// 不考虑空洞卷积, bs = 1
let (_, in_c, in_h, in_w) = input.dims4()?;
let (out_channel, _, ker_h, ker_w) = weight.dims4()?;
let out_h = ((in_h + 2 * padding - ker_h) / stride) + 1;
let out_w = ((in_w + 2 * padding - ker_w) / stride) + 1;
let num_kernels = in_c * out_h * out_w;
let mask_vec = if let Some(mask) = mask {
Some(mask.squeeze(0)?.to_vec3::<f32>()?)
} else {
None
};
let offset_vec = offset.squeeze(0)?.to_vec3::<f32>()?;
let input_vec = input.squeeze(0)?.to_vec3::<f32>()?;
let mut columns_vec = vec![vec![0.0f32; out_h * out_w]; in_c * ker_h * ker_w];
for index in 0..num_kernels {
let out_x = index % out_w;
let out_y = (index / out_w) % out_h;
let in_c = index / (out_w * out_h);
let out_c = in_c * ker_h * ker_w;
for i in 0..ker_h {
for j in 0..ker_w {
let mask_idx = i * ker_w + j;
let offset_idx = 2 * mask_idx;
let mask_value = if mask.is_some() {
mask_vec.as_ref().unwrap()[mask_idx][out_y][out_x]
} else {
1.0
};
let offset_h = offset_vec[offset_idx][out_y][out_x];
let offset_w = offset_vec[offset_idx + 1][out_y][out_x];
let y = ((out_y * stride - padding) + i) as f32 + offset_h;
let x = ((out_x * stride - padding) + j) as f32 + offset_w;
let val = if y <= -1.0 || in_h as f32 <= y || x <= -1.0 || in_w as f32 <= x {
0.0
} else {
let h_low = y.floor();
let w_low = x.floor();
let h_high = h_low + 1.0;
let w_high = w_low + 1.0;
let lh = y - h_low;
let lw = x - w_low;
let hh = 1.0 - lh;
let hw = 1.0 - lw;
let w1 = hh * hw;
let w2 = hh * lw;
let w3 = lh * hw;
let w4 = lh * lw;
let v1 = if h_low >= 0.0 && w_low >= 0.0 {
input_vec[in_c][h_low as usize][w_low as usize]
} else {
0.0
};
let v2 = if h_low >= 0.0 && w_high <= (in_w - 1) as f32 {
input_vec[in_c][h_low as usize][w_high as usize]
} else {
0.0
};
let v3 = if h_high <= (in_h - 1) as f32 && w_low >= 0.0 {
input_vec[in_c][h_high as usize][w_low as usize]
} else {
0.0
};
let v4 = if h_high <= (in_h - 1) as f32 && w_high <= (in_w - 1) as f32 {
input_vec[in_c][h_high as usize][w_high as usize]
} else {
0.0
};
w1 * v1 + w2 * v2 + w3 * v3 + w4 * v4
};
columns_vec[out_c + i * ker_w + j][out_y * out_w + out_x] = mask_value * val;
}
}
}
let columns = Tensor::new(columns_vec, weight.device())?;
let mut out =
weight
.flatten_from(1)?
.matmul(&columns)?
.reshape((1, out_channel, out_h, out_w))?;
if let Some(bias) = bias {
out = out.broadcast_add(bias)?;
}
Ok(out)
}
2026-01-07 21:46:01 +08:00
pub struct LlamaModel {
pub embed_tokens: Embedding,
layers: Vec<NaiveAttnGateUpDownMLPBlock>,
norm: RmsNorm,
rotary_emb: RoPE,
}
impl LlamaModel {
pub fn new(
vb: VarBuilder,
vocab_size: usize,
hidden_size: usize,
num_hidden_layers: usize,
num_attention_heads: usize,
num_key_value_heads: Option<usize>,
head_dim: Option<usize>,
attn_bias: bool,
attn_pp_name: &str,
o_proj_pp_name: Option<&str>,
intermediate_size: usize,
hidden_act: Activation,
mlp_bias: bool,
mlp_pp_name: &str,
norm_eps: f64,
input_norm_pp_name: &str,
post_norm_pp_name: &str,
rope_theta_base: f32,
) -> Result<Self> {
let embed_tokens = embedding(vocab_size, hidden_size, vb.pp("embed_tokens"))?;
let mut layers = vec![];
let vb_layers = vb.pp("layers");
for i in 0..num_hidden_layers {
let layers_i = NaiveAttnGateUpDownMLPBlock::new(
vb_layers.pp(i),
hidden_size,
num_attention_heads,
num_key_value_heads,
head_dim,
attn_bias,
attn_pp_name,
o_proj_pp_name,
intermediate_size,
hidden_act,
mlp_bias,
mlp_pp_name,
norm_eps,
input_norm_pp_name,
post_norm_pp_name,
)?;
layers.push(layers_i);
}
let norm = rms_norm(hidden_size, norm_eps, vb.pp("norm"))?;
let head_dim = head_dim.unwrap_or(hidden_size / num_attention_heads);
let rotary_emb = RoPE::new(head_dim, rope_theta_base, vb.device())?;
Ok(Self {
embed_tokens,
layers,
norm,
rotary_emb,
})
}
pub fn forward(&mut self, inputs_embeds: &Tensor, seqlen_offset: usize) -> Result<Tensor> {
let (b_size, seq_len, _) = inputs_embeds.dims3()?;
let (cos, sin) = self
.rotary_emb
.forward(seqlen_offset, seq_len, inputs_embeds.device())?;
let mut xs = inputs_embeds.clone();
let attention_mask: Option<Tensor> = {
if seq_len <= 1 {
None
} else {
Some(prepare_causal_attention_mask(
b_size,
seq_len,
0,
xs.device(),
)?)
}
};
for layer in self.layers.iter_mut() {
xs = layer.forward(&xs, &cos, &sin, attention_mask.as_ref())?;
}
let xs = xs.apply(&self.norm)?;
Ok(xs)
}
pub fn clear_kv_cache(&mut self) {
for layer in self.layers.iter_mut() {
layer.clear_kv_cache()
}
}
}
pub struct LlamaForCausalLM {
pub model: LlamaModel,
lm_head: Linear,
}
impl LlamaForCausalLM {
pub fn new(
vb: VarBuilder,
vocab_size: usize,
hidden_size: usize,
num_hidden_layers: usize,
num_attention_heads: usize,
num_key_value_heads: Option<usize>,
head_dim: Option<usize>,
attn_bias: bool,
attn_pp_name: &str,
o_proj_pp_name: Option<&str>,
intermediate_size: usize,
hidden_act: Activation,
mlp_bias: bool,
mlp_pp_name: &str,
norm_eps: f64,
input_norm_pp_name: &str,
post_norm_pp_name: &str,
rope_theta_base: f32,
) -> Result<Self> {
let model = LlamaModel::new(
vb.pp("model"),
vocab_size,
hidden_size,
num_hidden_layers,
num_attention_heads,
num_key_value_heads,
head_dim,
attn_bias,
attn_pp_name,
o_proj_pp_name,
intermediate_size,
hidden_act,
mlp_bias,
mlp_pp_name,
norm_eps,
input_norm_pp_name,
post_norm_pp_name,
rope_theta_base,
)?;
let lm_head = linear_no_bias(hidden_size, vocab_size, vb.pp("lm_head"))?;
Ok(Self { model, lm_head })
}
pub fn forward(&mut self, inputs_embeds: &Tensor, seqlen_offset: usize) -> Result<Tensor> {
let outputs = self.model.forward(inputs_embeds, seqlen_offset)?;
let seq_len = outputs.dim(1)?;
let hidden_state = outputs.narrow(1, seq_len - 1, 1)?;
let logits = self.lm_head.forward(&hidden_state)?;
Ok(logits)
}
pub fn clear_kv_cache(&mut self) {
self.model.clear_kv_cache();
}
}