Add a batch dimension on the bert example.

This commit is contained in:
laurent
2023-07-04 06:10:52 +01:00
parent 8e4d298c90
commit a57b314780
4 changed files with 32 additions and 15 deletions

View File

@ -75,6 +75,9 @@ enum HiddenAct {
impl HiddenAct {
fn forward(&self, xs: &Tensor) -> candle::Result<Tensor> {
match self {
// TODO: The all-MiniLM-L6-v2 model uses "gelu" whereas this is "gelu_new", this explains some
// small numerical difference.
// https://github.com/huggingface/transformers/blob/cd4584e3c809bb9e1392ccd3fe38b40daba5519a/src/transformers/activations.py#L213
Self::Gelu => xs.gelu(),
Self::Relu => xs.relu(),
}
@ -196,7 +199,9 @@ impl Linear {
}
fn forward(&self, x: &Tensor) -> Result<Tensor> {
let x = x.matmul(&self.weight.t()?)?;
let (bsize, _, _) = x.shape().r3()?;
let w = self.weight.broadcast_left(bsize)?.t()?;
let x = x.matmul(&w)?;
let x = x.broadcast_add(&self.bias)?;
Ok(x)
}
@ -236,12 +241,11 @@ impl LayerNorm {
}
fn forward(&self, x: &Tensor) -> Result<Tensor> {
let (seq_len, hidden_size) = x.shape().r2()?;
let mean_x = (x.sum(&[1])? / hidden_size as f64)?;
let (_bsize, _seq_len, hidden_size) = x.shape().r3()?;
let mean_x = (x.sum(&[2])? / hidden_size as f64)?;
let x = x.broadcast_sub(&mean_x)?;
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 + self.eps)?.sqrt()?)?;
let norm_x = ((&x * &x)?.sum(&[2])? / hidden_size as f64)?;
let x_normed = x.broadcast_div(&(norm_x + self.eps)?.sqrt()?)?;
let x = x_normed
.broadcast_mul(&self.weight)?
.broadcast_add(&self.bias)?;
@ -301,7 +305,7 @@ impl BertEmbeddings {
}
fn forward(&self, input_ids: &Tensor, token_type_ids: &Tensor) -> Result<Tensor> {
let seq_len = input_ids.shape().r1()?;
let (_bsize, seq_len) = input_ids.shape().r2()?;
let input_embeddings = self.word_embeddings.forward(input_ids)?;
let token_type_embeddings = self.token_type_embeddings.forward(token_type_ids)?;
let mut embeddings = (&input_embeddings + token_type_embeddings)?;
@ -309,7 +313,7 @@ impl BertEmbeddings {
// TODO: Proper absolute positions?
let position_ids = (0..seq_len as u32).collect::<Vec<_>>();
let position_ids = Tensor::new(&position_ids[..], &input_ids.device())?;
embeddings = (&embeddings + position_embeddings.forward(&position_ids)?)?
embeddings = embeddings.broadcast_add(&position_embeddings.forward(&position_ids)?)?
}
let embeddings = self.layer_norm.forward(&embeddings)?;
let embeddings = self.dropout.forward(&embeddings)?;
@ -351,7 +355,7 @@ impl BertSelfAttention {
new_x_shape.push(self.num_attention_heads);
new_x_shape.push(self.attention_head_size);
// Be cautious about the transposition if adding a batch dim!
let xs = xs.reshape(new_x_shape.as_slice())?.transpose(0, 1)?;
let xs = xs.reshape(new_x_shape.as_slice())?.transpose(1, 2)?;
Ok(xs.contiguous()?)
}
@ -370,7 +374,7 @@ impl BertSelfAttention {
let attention_probs = self.dropout.forward(&attention_probs)?;
let context_layer = attention_probs.matmul(&value_layer)?;
let context_layer = context_layer.transpose(0, 1)?.contiguous()?;
let context_layer = context_layer.transpose(1, 2)?.contiguous()?;
let context_layer = context_layer.flatten(Some(context_layer.rank() - 2), None)?;
Ok(context_layer)
}
@ -616,7 +620,7 @@ fn main() -> Result<()> {
.map_err(E::msg)?
.get_ids()
.to_vec();
let token_ids = Tensor::new(&tokens[..], &device)?;
let token_ids = Tensor::new(&tokens[..], &device)?.unsqueeze(0)?;
println!("{token_ids}");
let token_type_ids = token_ids.zeros_like()?;
let ys = model.forward(&token_ids, &token_type_ids)?;