Enable the new layer-norm. (#2213)

* Enable the new layer-norm.

* Shape fixes.
This commit is contained in:
Laurent Mazare
2024-05-24 16:48:21 +02:00
committed by GitHub
parent 1df2bddccf
commit 3ceca9901a
3 changed files with 23 additions and 13 deletions

View File

@ -11,8 +11,8 @@
//! use candle_nn::{LayerNorm, Module};
//! # fn main() -> candle::Result<()> {
//!
//! let w = Tensor::new(1f32, &Cpu)?;
//! let b = Tensor::new(0f32, &Cpu)?;
//! let w = Tensor::new(&[1f32, 1f32, 1f32], &Cpu)?;
//! let b = Tensor::new(&[0f32, 0f32, 0f32], &Cpu)?;
//! let layer = LayerNorm::new(w, b, 1e-5);
//!
//! let xs = Tensor::new(
@ -107,6 +107,11 @@ impl LayerNorm {
impl Module for LayerNorm {
fn forward(&self, x: &Tensor) -> Result<Tensor> {
if x.is_contiguous() && self.remove_mean {
if let Some(bias) = self.bias.as_ref() {
return crate::ops::layer_norm(x, &self.weight, bias, self.eps as f32);
}
}
let x_dtype = x.dtype();
let internal_dtype = match x_dtype {
DType::F16 | DType::BF16 => DType::F32,

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@ -13,6 +13,12 @@ fn layer_norm() -> Result<()> {
let device = &Device::Cpu;
let w = Tensor::new(&[3f32], device)?;
let b = Tensor::new(&[0.5f32], device)?;
let ln2 = LayerNorm::new(Tensor::cat(&[&w, &w], 0)?, Tensor::cat(&[&b, &b], 0)?, 1e-8);
let ln3 = LayerNorm::new(
Tensor::cat(&[&w, &w, &w], 0)?,
Tensor::cat(&[&b, &b, &b], 0)?,
1e-8,
);
let ln = LayerNorm::new(w, b, 1e-8);
let two = Tensor::new(&[[[2f32]]], device)?;
@ -20,11 +26,11 @@ fn layer_norm() -> Result<()> {
assert_eq!(res.to_vec1::<f32>()?, [0.5f32]);
let inp = Tensor::new(&[[[4f32, 0f32]]], device)?;
let res = ln.forward(&inp)?;
let res = ln2.forward(&inp)?;
assert_eq!(res.to_vec3::<f32>()?, [[[3.5f32, -2.5]]]);
let inp = Tensor::new(&[[[1f32, 2., 3.], [4., 5., 6.], [9., 8., 7.]]], device)?;
let res = ln.forward(&inp)?;
let res = ln3.forward(&inp)?;
assert_eq!(
test_utils::to_vec3_round(&res, 4)?,
[[
@ -35,7 +41,10 @@ fn layer_norm() -> Result<()> {
);
let mean = (res.sum_keepdim(2)? / 3.0)?;
// The average value should be `b`.
assert_eq!(mean.to_vec3::<f32>()?, [[[0.5], [0.5], [0.5]]]);
assert_eq!(
test_utils::to_vec3_round(&mean, 4)?,
[[[0.5], [0.5], [0.5]]]
);
let std = (res.broadcast_sub(&mean)?.sqr()?.sum_keepdim(2)?.sqrt()? / 3.0)?;
// The standard deviation should be sqrt(`w`).
assert_eq!(

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@ -56,24 +56,20 @@ impl RotaryEmbedding {
.to_dtype(DType::F32)?
.reshape((cfg.max_position_embeddings, 1))?;
let freqs = t.matmul(&inv_freq)?;
let emb = Tensor::cat(&[&freqs, &freqs], D::Minus1)?;
Ok(Self {
dim,
sin: emb.sin()?,
cos: emb.cos()?,
sin: freqs.sin()?,
cos: freqs.cos()?,
})
}
fn apply_rotary_emb(&self, xs: &Tensor, seqlen_offset: usize) -> Result<Tensor> {
let (_b_size, _num_heads, seq_len, _headdim) = xs.dims4()?;
let xs_rot = xs.i((.., .., .., ..self.dim))?;
let xs_rot = xs.i((.., .., .., ..self.dim))?.contiguous()?;
let xs_pass = xs.i((.., .., .., self.dim..))?;
let xs12 = xs_rot.chunk(2, D::Minus1)?;
let (xs1, xs2) = (&xs12[0], &xs12[1]);
let c = self.cos.narrow(0, seqlen_offset, seq_len)?;
let s = self.sin.narrow(0, seqlen_offset, seq_len)?;
let rotate_half = Tensor::cat(&[&xs2.neg()?, xs1], D::Minus1)?;
let xs_rot = (xs_rot.broadcast_mul(&c)? + rotate_half.broadcast_mul(&s)?)?;
let xs_rot = candle_nn::rotary_emb::rope(&xs_rot, &c, &s)?;
Tensor::cat(&[&xs_rot, &xs_pass], D::Minus1)
}
}