File size: 3,839 Bytes
72c0672 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 | use crate::parallelism::*;
use crate::tokenizer::{Encoding, Result};
use serde::{Deserialize, Serialize};
/// The various possible padding directions.
#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
pub enum PaddingDirection {
Left,
Right,
}
impl std::convert::AsRef<str> for PaddingDirection {
fn as_ref(&self) -> &str {
match self {
PaddingDirection::Left => "left",
PaddingDirection::Right => "right",
}
}
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PaddingParams {
pub strategy: PaddingStrategy,
pub direction: PaddingDirection,
pub pad_to_multiple_of: Option<usize>,
pub pad_id: u32,
pub pad_type_id: u32,
pub pad_token: String,
}
impl Default for PaddingParams {
fn default() -> Self {
Self {
strategy: PaddingStrategy::BatchLongest,
direction: PaddingDirection::Right,
pad_to_multiple_of: None,
pad_id: 0,
pad_type_id: 0,
pad_token: String::from("[PAD]"),
}
}
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum PaddingStrategy {
BatchLongest,
Fixed(usize),
}
pub fn pad_encodings(encodings: &mut [Encoding], params: &PaddingParams) -> Result<()> {
if encodings.is_empty() {
return Ok(());
}
let mut pad_length = match params.strategy {
PaddingStrategy::Fixed(size) => size,
PaddingStrategy::BatchLongest => encodings
.maybe_par_iter()
.map(|e| e.get_ids().len())
.max()
.unwrap(),
};
if let Some(multiple) = params.pad_to_multiple_of {
if multiple > 0 && pad_length % multiple > 0 {
pad_length += multiple - pad_length % multiple;
}
}
encodings.maybe_par_iter_mut().for_each(|encoding| {
encoding.pad(
pad_length,
params.pad_id,
params.pad_type_id,
¶ms.pad_token,
params.direction,
)
});
Ok(())
}
#[cfg(test)]
mod tests {
use super::*;
use crate::tokenizer::Encoding;
use std::collections::HashMap;
#[test]
fn pad_to_multiple() {
fn get_encodings() -> [Encoding; 2] {
[
Encoding::new(
vec![0, 1, 2, 3, 4],
vec![],
vec![],
vec![],
vec![],
vec![],
vec![],
vec![],
HashMap::new(),
),
Encoding::new(
vec![0, 1, 2],
vec![],
vec![],
vec![],
vec![],
vec![],
vec![],
vec![],
HashMap::new(),
),
]
}
// Test fixed
let mut encodings = get_encodings();
let mut params = PaddingParams {
strategy: PaddingStrategy::Fixed(7),
direction: PaddingDirection::Right,
pad_to_multiple_of: Some(8),
pad_id: 0,
pad_type_id: 0,
pad_token: String::from("[PAD]"),
};
pad_encodings(&mut encodings, ¶ms).unwrap();
assert!(encodings.iter().all(|e| e.get_ids().len() == 8));
// Test batch
let mut encodings = get_encodings();
params.strategy = PaddingStrategy::BatchLongest;
params.pad_to_multiple_of = Some(6);
pad_encodings(&mut encodings, ¶ms).unwrap();
assert!(encodings.iter().all(|e| e.get_ids().len() == 6));
// Do not crash with 0
params.pad_to_multiple_of = Some(0);
pad_encodings(&mut encodings, ¶ms).unwrap();
}
}
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