add fairseq0.10.2

examples/byte_level_bpe/README.md

+# Neural Machine Translation with Byte-Level Subwords
+
+https://arxiv.org/abs/1909.03341
+
+We provide an implementation of byte-level byte-pair encoding (BBPE), taking IWSLT 2017 Fr-En translation as
+example.
+
+## Data
+Get data and generate fairseq binary dataset:
+```bash
+bash ./get_data.sh
+```
+
+## Model Training
+Train Transformer model with Bi-GRU embedding contextualization (implemented in `gru_transformer.py`):
+```bash
+# VOCAB=bytes
+# VOCAB=chars
+VOCAB=bbpe2048
+# VOCAB=bpe2048
+# VOCAB=bbpe4096
+# VOCAB=bpe4096
+# VOCAB=bpe16384
+```
+```bash
+fairseq-train "data/bin_${VOCAB}" --task translation --user-dir examples/byte_level_bpe/gru_transformer \
+    --arch gru_transformer --encoder-layers 2 --decoder-layers 2 --dropout 0.3 --share-all-embeddings \
+    --optimizer adam --adam-betas '(0.9, 0.98)' \
+    --lr 5e-4 --lr-scheduler inverse_sqrt --warmup-updates 4000 \
+    --criterion label_smoothed_cross_entropy --label-smoothing 0.1 \
+    --log-format 'simple' --log-interval 100 --save-dir "checkpoints/${VOCAB}" \
+    --batch-size 100 --max-update 100000 --update-freq 2
+```
+
+## Generation
+`fairseq-generate` requires bytes (BBPE) decoder to convert byte-level representation back to characters:
+```bash
+# BPE=--bpe bytes
+# BPE=--bpe characters
+BPE=--bpe byte_bpe --sentencepiece-model-path data/spm_bbpe2048.model
+# BPE=--bpe sentencepiece --sentencepiece-model data/spm_bpe2048.model
+# BPE=--bpe byte_bpe --sentencepiece-model-path data/spm_bbpe4096.model
+# BPE=--bpe sentencepiece --sentencepiece-model data/spm_bpe4096.model
+# BPE=--bpe sentencepiece --sentencepiece-model data/spm_bpe16384.model
+```
+
+```bash
+fairseq-generate "data/bin_${VOCAB}" --task translation --user-dir examples/byte_level_bpe/gru_transformer \
+    --source-lang fr --gen-subset test --sacrebleu --path "checkpoints/${VOCAB}/checkpoint_last.pt" \
+    --tokenizer moses --moses-target-lang en ${BPE}
+```
+When using `fairseq-interactive`, bytes (BBPE) encoder/decoder is required to tokenize input data and detokenize model predictions:
+```bash
+fairseq-interactive "data/bin_${VOCAB}" --task translation --user-dir examples/byte_level_bpe/gru_transformer \
+    --path "checkpoints/${VOCAB}/checkpoint_last.pt" --input data/test.fr --tokenizer moses --moses-source-lang fr \
+    --moses-target-lang en ${BPE} --buffer-size 1000 --max-tokens 10000
+```
+
+## Results
+| Vocabulary    | Model  | BLEU |
+|:-------------:|:-------------:|:-------------:|
+| Joint BPE 16k ([Kudo, 2018](https://arxiv.org/abs/1804.10959)) | 512d LSTM 2+2 | 33.81 |
+| Joint BPE 16k | Transformer base 2+2 (w/ GRU) | 36.64 (36.72) |
+| Joint BPE 4k | Transformer base 2+2 (w/ GRU) | 35.49 (36.10) |
+| Joint BBPE 4k | Transformer base 2+2 (w/ GRU) | 35.61 (35.82) |
+| Joint BPE 2k | Transformer base 2+2 (w/ GRU) | 34.87 (36.13) |
+| Joint BBPE 2k | Transformer base 2+2 (w/ GRU) | 34.98 (35.43) |
+| Characters | Transformer base 2+2 (w/ GRU) | 31.78 (33.30) |
+| Bytes | Transformer base 2+2 (w/ GRU) | 31.57 (33.62) |
+
+
+## Citation
+```
+@misc{wang2019neural,
+    title={Neural Machine Translation with Byte-Level Subwords},
+    author={Changhan Wang and Kyunghyun Cho and Jiatao Gu},
+    year={2019},
+    eprint={1909.03341},
+    archivePrefix={arXiv},
+    primaryClass={cs.CL}
+}
+```
+
+
+## Contact
+Changhan Wang ([changhan@fb.com](mailto:changhan@fb.com)),
+Kyunghyun Cho ([kyunghyuncho@fb.com](mailto:kyunghyuncho@fb.com)),
+Jiatao Gu ([jgu@fb.com](mailto:jgu@fb.com))

examples/byte_level_bpe/get_bitext.py

+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+
+import argparse
+import os
+import os.path as op
+from collections import namedtuple
+from multiprocessing import cpu_count
+from typing import List, Optional
+
+import sentencepiece as sp
+from fairseq.data.encoders.byte_bpe import ByteBPE
+from fairseq.data.encoders.byte_utils import byte_encode
+from fairseq.data.encoders.bytes import Bytes
+from fairseq.data.encoders.characters import Characters
+from fairseq.data.encoders.moses_tokenizer import MosesTokenizer
+from fairseq.data.encoders.sentencepiece_bpe import SentencepieceBPE
+
+
+SPLITS = ["train", "valid", "test"]
+
+
+def _convert_xml(in_path: str, out_path: str):
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            ss = s.strip()
+            if not ss.startswith("<seg"):
+                continue
+            ss = ss.replace("</seg>", "").split('">')
+            assert len(ss) == 2
+            f_o.write(ss[1].strip() + "\n")
+
+
+def _convert_train(in_path: str, out_path: str):
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            ss = s.strip()
+            if ss.startswith("<"):
+                continue
+            f_o.write(ss.strip() + "\n")
+
+
+def _get_bytes(in_path: str, out_path: str):
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            f_o.write(Bytes.encode(s.strip()) + "\n")
+
+
+def _get_chars(in_path: str, out_path: str):
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            f_o.write(Characters.encode(s.strip()) + "\n")
+
+
+def pretokenize(in_path: str, out_path: str, src: str, tgt: str):
+    Args = namedtuple(
+        "Args",
+        [
+            "moses_source_lang",
+            "moses_target_lang",
+            "moses_no_dash_splits",
+            "moses_no_escape",
+        ],
+    )
+    args = Args(
+        moses_source_lang=src,
+        moses_target_lang=tgt,
+        moses_no_dash_splits=False,
+        moses_no_escape=False,
+    )
+    pretokenizer = MosesTokenizer(args)
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            f_o.write(pretokenizer.encode(s.strip()) + "\n")
+
+
+def _convert_to_bchar(in_path_prefix: str, src: str, tgt: str, out_path: str):
+    with open(out_path, "w") as f_o:
+        for lang in [src, tgt]:
+            with open(f"{in_path_prefix}.{lang}") as f:
+                for s in f:
+                    f_o.write(byte_encode(s.strip()) + "\n")
+
+
+def _get_bpe(in_path: str, model_prefix: str, vocab_size: int):
+    arguments = [
+        f"--input={in_path}",
+        f"--model_prefix={model_prefix}",
+        f"--model_type=bpe",
+        f"--vocab_size={vocab_size}",
+        "--character_coverage=1.0",
+        "--normalization_rule_name=identity",
+        f"--num_threads={cpu_count()}",
+    ]
+    sp.SentencePieceTrainer.Train(" ".join(arguments))
+
+
+def _apply_bbpe(model_path: str, in_path: str, out_path: str):
+    Args = namedtuple("Args", ["sentencepiece_model_path"])
+    args = Args(sentencepiece_model_path=model_path)
+    tokenizer = ByteBPE(args)
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            f_o.write(tokenizer.encode(s.strip()) + "\n")
+
+
+def _apply_bpe(model_path: str, in_path: str, out_path: str):
+    Args = namedtuple("Args", ["sentencepiece_model"])
+    args = Args(sentencepiece_model=model_path)
+    tokenizer = SentencepieceBPE(args)
+    with open(in_path) as f, open(out_path, "w") as f_o:
+        for s in f:
+            f_o.write(tokenizer.encode(s.strip()) + "\n")
+
+
+def _concat_files(in_paths: List[str], out_path: str):
+    with open(out_path, "w") as f_o:
+        for p in in_paths:
+            with open(p) as f:
+                for r in f:
+                    f_o.write(r)
+
+
+def preprocess_iwslt17(
+    root: str,
+    src: str,
+    tgt: str,
+    bpe_size: Optional[int],
+    need_chars: bool,
+    bbpe_size: Optional[int],
+    need_bytes: bool,
+):
+    # extract bitext
+    in_root = op.join(root, f"{src}-{tgt}")
+    for lang in [src, tgt]:
+        _convert_train(
+            op.join(in_root, f"train.tags.{src}-{tgt}.{lang}"),
+            op.join(root, f"train.{lang}"),
+        )
+        _convert_xml(
+            op.join(in_root, f"IWSLT17.TED.dev2010.{src}-{tgt}.{lang}.xml"),
+            op.join(root, f"valid.{lang}"),
+        )
+        _convert_xml(
+            op.join(in_root, f"IWSLT17.TED.tst2015.{src}-{tgt}.{lang}.xml"),
+            op.join(root, f"test.{lang}"),
+        )
+    # pre-tokenize
+    for lang in [src, tgt]:
+        for split in SPLITS:
+            pretokenize(
+                op.join(root, f"{split}.{lang}"),
+                op.join(root, f"{split}.moses.{lang}"),
+                src,
+                tgt,
+            )
+    # tokenize with BPE vocabulary
+    if bpe_size is not None:
+        # learn vocabulary
+        concated_train_path = op.join(root, "train.all")
+        _concat_files(
+            [op.join(root, "train.moses.fr"), op.join(root, "train.moses.en")],
+            concated_train_path,
+        )
+        bpe_model_prefix = op.join(root, f"spm_bpe{bpe_size}")
+        _get_bpe(concated_train_path, bpe_model_prefix, bpe_size)
+        os.remove(concated_train_path)
+        # apply
+        for lang in [src, tgt]:
+            for split in SPLITS:
+                _apply_bpe(
+                    bpe_model_prefix + ".model",
+                    op.join(root, f"{split}.moses.{lang}"),
+                    op.join(root, f"{split}.moses.bpe{bpe_size}.{lang}"),
+                )
+    # tokenize with bytes vocabulary
+    if need_bytes:
+        for lang in [src, tgt]:
+            for split in SPLITS:
+                _get_bytes(
+                    op.join(root, f"{split}.moses.{lang}"),
+                    op.join(root, f"{split}.moses.bytes.{lang}"),
+                )
+    # tokenize with characters vocabulary
+    if need_chars:
+        for lang in [src, tgt]:
+            for split in SPLITS:
+                _get_chars(
+                    op.join(root, f"{split}.moses.{lang}"),
+                    op.join(root, f"{split}.moses.chars.{lang}"),
+                )
+    # tokenize with byte-level BPE vocabulary
+    if bbpe_size is not None:
+        # learn vocabulary
+        bchar_path = op.join(root, "train.bchar")
+        _convert_to_bchar(op.join(root, "train.moses"), src, tgt, bchar_path)
+        bbpe_model_prefix = op.join(root, f"spm_bbpe{bbpe_size}")
+        _get_bpe(bchar_path, bbpe_model_prefix, bbpe_size)
+        os.remove(bchar_path)
+        # apply
+        for lang in [src, tgt]:
+            for split in SPLITS:
+                _apply_bbpe(
+                    bbpe_model_prefix + ".model",
+                    op.join(root, f"{split}.moses.{lang}"),
+                    op.join(root, f"{split}.moses.bbpe{bbpe_size}.{lang}"),
+                )
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--root", type=str, default="data")
+    parser.add_argument(
+        "--bpe-vocab",
+        default=None,
+        type=int,
+        help="Generate tokenized bitext with BPE of size K."
+        "Default to None (disabled).",
+    )
+    parser.add_argument(
+        "--bbpe-vocab",
+        default=None,
+        type=int,
+        help="Generate tokenized bitext with BBPE of size K."
+        "Default to None (disabled).",
+    )
+    parser.add_argument(
+        "--byte-vocab",
+        action="store_true",
+        help="Generate tokenized bitext with bytes vocabulary",
+    )
+    parser.add_argument(
+        "--char-vocab",
+        action="store_true",
+        help="Generate tokenized bitext with chars vocabulary",
+    )
+    args = parser.parse_args()
+
+    preprocess_iwslt17(
+        args.root,
+        "fr",
+        "en",
+        args.bpe_vocab,
+        args.char_vocab,
+        args.bbpe_vocab,
+        args.byte_vocab,
+    )
+
+
+if __name__ == "__main__":
+    main()

examples/byte_level_bpe/get_data.sh

+#!/bin/bash
+
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+PY_BIN_ROOT=
+
+# PyPI dependency
+${PY_BIN_ROOT}pip install sentencepiece sacremoses
+
+# Get data
+if [ ! -d "data" ]; then
+  mkdir data
+fi
+
+if [ ! -f "data/fr-en.tgz" ]; then
+  wget https://wit3.fbk.eu/archive/2017-01-trnted/texts/fr/en/fr-en.tgz -P data
+  tar xvf data/fr-en.tgz -C data
+fi
+${PY_BIN_ROOT}python get_bitext.py --bpe-vocab 16384 --byte-vocab --char-vocab
+for VOCAB_SIZE in 2048 4096; do
+  ${PY_BIN_ROOT}python get_bitext.py --bpe-vocab ${VOCAB_SIZE} --bbpe-vocab ${VOCAB_SIZE}
+done
+rm -r data/fr-en data/fr-en.tgz
+
+# Generate binary dataset
+${PY_BIN_ROOT}/fairseq-preprocess --source-lang fr --target-lang en --destdir data/bin_bpe16384 --joined-dictionary \
+  --workers "$(nproc)" --trainpref data/train.moses.bpe16384 --validpref data/valid.moses.bpe16384 \
+  --testpref data/test.moses.bpe16384
+
+${PY_BIN_ROOT}/fairseq-preprocess --source-lang fr --target-lang en --destdir data/bin_bytes --joined-dictionary \
+  --workers "$(nproc)" --trainpref data/train.moses.bytes --validpref data/valid.moses.bytes \
+  --testpref data/test.moses.bytes
+
+${PY_BIN_ROOT}/fairseq-preprocess --source-lang fr --target-lang en --destdir data/bin_chars --joined-dictionary \
+  --workers "$(nproc)" --trainpref data/train.moses.chars --validpref data/valid.moses.chars \
+  --testpref data/test.moses.chars
+
+for VOCAB_SIZE in 2048 4096; do
+  for TYPE in bbpe bpe; do
+    ${PY_BIN_ROOT}/fairseq-preprocess --source-lang fr --target-lang en --destdir "data/bin_${TYPE}${VOCAB_SIZE}" \
+      --joined-dictionary --workers "$(nproc)" --trainpref "data/train.moses.${TYPE}${VOCAB_SIZE}" \
+      --validpref "data/valid.moses.${TYPE}${VOCAB_SIZE}" --testpref "data/test.moses.${TYPE}${VOCAB_SIZE}"
+  done
+done

examples/byte_level_bpe/gru_transformer.py

+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+import torch.nn as nn
+import torch.nn.functional as F
+from fairseq.models import register_model, register_model_architecture
+from fairseq.models.transformer import TransformerEncoder, TransformerModel
+
+
+@register_model("gru_transformer")
+class GRUTransformerModel(TransformerModel):
+    @classmethod
+    def build_encoder(cls, args, src_dict, embed_tokens):
+        return GRUTransformerEncoder(args, src_dict, embed_tokens)
+
+
+class GRUTransformerEncoder(TransformerEncoder):
+    def __init__(self, args, dictionary, embed_tokens):
+        super().__init__(args, dictionary, embed_tokens)
+        self.emb_ctx = nn.GRU(
+            input_size=embed_tokens.embedding_dim,
+            hidden_size=embed_tokens.embedding_dim // 2,
+            num_layers=1,
+            bidirectional=True,
+        )
+
+    def forward_embedding(self, src_tokens):
+        # embed tokens and positions
+        x = embed = self.embed_scale * self.embed_tokens(src_tokens)
+        if self.embed_positions is not None:
+            x = embed + self.embed_positions(src_tokens)
+
+        # contextualize embeddings
+        x = x.transpose(0, 1)
+        x = self.dropout_module(x)
+        x, _ = self.emb_ctx.forward(x)
+        x = x.transpose(0, 1)
+
+        if self.layernorm_embedding is not None:
+            x = self.layernorm_embedding(x)
+        x = self.dropout_module(x)
+        return x, embed
+
+
+@register_model_architecture("gru_transformer", "gru_transformer")
+def gru_transformer_base_architecture(args):
+    args.encoder_embed_path = getattr(args, "encoder_embed_path", None)
+    args.encoder_embed_dim = getattr(args, "encoder_embed_dim", 512)
+    args.encoder_ffn_embed_dim = getattr(args, "encoder_ffn_embed_dim", 2048)
+    args.encoder_layers = getattr(args, "encoder_layers", 6)
+    args.encoder_attention_heads = getattr(args, "encoder_attention_heads", 8)
+    args.encoder_normalize_before = getattr(args, "encoder_normalize_before", False)
+    args.encoder_learned_pos = getattr(args, "encoder_learned_pos", False)
+    args.decoder_embed_path = getattr(args, "decoder_embed_path", None)
+    args.decoder_embed_dim = getattr(args, "decoder_embed_dim", args.encoder_embed_dim)
+    args.decoder_ffn_embed_dim = getattr(
+        args, "decoder_ffn_embed_dim", args.encoder_ffn_embed_dim
+    )
+    args.decoder_layers = getattr(args, "decoder_layers", 6)
+    args.decoder_attention_heads = getattr(args, "decoder_attention_heads", 8)
+    args.decoder_normalize_before = getattr(args, "decoder_normalize_before", False)
+    args.decoder_learned_pos = getattr(args, "decoder_learned_pos", False)
+    args.attention_dropout = getattr(args, "attention_dropout", 0.0)
+    args.activation_dropout = getattr(args, "activation_dropout", 0.0)
+    args.activation_fn = getattr(args, "activation_fn", "relu")
+    args.dropout = getattr(args, "dropout", 0.1)
+    args.adaptive_softmax_cutoff = getattr(args, "adaptive_softmax_cutoff", None)
+    args.adaptive_softmax_dropout = getattr(args, "adaptive_softmax_dropout", 0)
+    args.share_decoder_input_output_embed = getattr(
+        args, "share_decoder_input_output_embed", False
+    )
+    args.share_all_embeddings = getattr(args, "share_all_embeddings", False)
+    args.no_token_positional_embeddings = getattr(
+        args, "no_token_positional_embeddings", False
+    )
+    args.adaptive_input = getattr(args, "adaptive_input", False)
+    args.no_cross_attention = getattr(args, "no_cross_attention", False)
+    args.cross_self_attention = getattr(args, "cross_self_attention", False)
+    args.layer_wise_attention = getattr(args, "layer_wise_attention", False)
+
+    args.decoder_output_dim = getattr(
+        args, "decoder_output_dim", args.decoder_embed_dim
+    )
+    args.decoder_input_dim = getattr(args, "decoder_input_dim", args.decoder_embed_dim)
+
+    args.no_scale_embedding = getattr(args, "no_scale_embedding", False)
+    args.layernorm_embedding = getattr(args, "layernorm_embedding", False)
+
+
+@register_model_architecture("gru_transformer", "gru_transformer_big")
+def gru_transformer_big(args):
+    args.encoder_embed_dim = getattr(args, "encoder_embed_dim", 1024)
+    args.encoder_ffn_embed_dim = getattr(args, "encoder_ffn_embed_dim", 4096)
+    args.encoder_attention_heads = getattr(args, "encoder_attention_heads", 16)
+    args.encoder_normalize_before = getattr(args, "encoder_normalize_before", False)
+    args.decoder_embed_dim = getattr(args, "decoder_embed_dim", 1024)
+    args.decoder_ffn_embed_dim = getattr(args, "decoder_ffn_embed_dim", 4096)
+    args.decoder_attention_heads = getattr(args, "decoder_attention_heads", 16)
+    args.dropout = getattr(args, "dropout", 0.3)
+    gru_transformer_base_architecture(args)

examples/camembert/README.md

+# CamemBERT: a Tasty French Language Model
+
+## Introduction
+
+[CamemBERT](https://arxiv.org/abs/1911.03894) is a pretrained language model trained on 138GB of French text based on RoBERTa.
+
+Also available in [github.com/huggingface/transformers](https://github.com/huggingface/transformers/).
+
+## Pre-trained models
+
+| Model                          | #params | Download                                                                                                                 | Arch. | Training data                     |
+|--------------------------------|---------|--------------------------------------------------------------------------------------------------------------------------|-------|-----------------------------------|
+| `camembert` / `camembert-base` | 110M    | [camembert-base.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-base.tar.gz)                             | Base  | OSCAR (138 GB of text)            |
+| `camembert-large`              | 335M    | [camembert-large.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-large.tar.gz)                           | Large | CCNet (135 GB of text)            |
+| `camembert-base-ccnet`         | 110M    | [camembert-base-ccnet.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-base-ccnet.tar.gz)                 | Base  | CCNet (135 GB of text)            |
+| `camembert-base-wikipedia-4gb` | 110M    | [camembert-base-wikipedia-4gb.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-base-wikipedia-4gb.tar.gz) | Base  | Wikipedia (4 GB of text)          |
+| `camembert-base-oscar-4gb`     | 110M    | [camembert-base-oscar-4gb.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-base-oscar-4gb.tar.gz)         | Base  | Subsample of OSCAR (4 GB of text) |
+| `camembert-base-ccnet-4gb`     | 110M    | [camembert-base-ccnet-4gb.tar.gz](https://dl.fbaipublicfiles.com/fairseq/models/camembert-base-ccnet-4gb.tar.gz)         | Base  | Subsample of CCNet (4 GB of text) |
+
+## Example usage
+
+### fairseq
+##### Load CamemBERT from torch.hub (PyTorch >= 1.1):
+```python
+import torch
+camembert = torch.hub.load('pytorch/fairseq', 'camembert')
+camembert.eval()  # disable dropout (or leave in train mode to finetune)
+```
+
+##### Load CamemBERT (for PyTorch 1.0 or custom models):
+```python
+# Download camembert model
+wget https://dl.fbaipublicfiles.com/fairseq/models/camembert-base.tar.gz
+tar -xzvf camembert.tar.gz
+
+# Load the model in fairseq
+from fairseq.models.roberta import CamembertModel
+camembert = CamembertModel.from_pretrained('/path/to/camembert')
+camembert.eval()  # disable dropout (or leave in train mode to finetune)
+```
+
+##### Filling masks:
+```python
+masked_line = 'Le camembert est <mask> :)'
+camembert.fill_mask(masked_line, topk=3)
+# [('Le camembert est délicieux :)', 0.4909118115901947, ' délicieux'),
+#  ('Le camembert est excellent :)', 0.10556942224502563, ' excellent'),
+#  ('Le camembert est succulent :)', 0.03453322499990463, ' succulent')]
+```
+
+##### Extract features from Camembert:
+```python
+# Extract the last layer's features
+line = "J'aime le camembert !"
+tokens = camembert.encode(line)
+last_layer_features = camembert.extract_features(tokens)
+assert last_layer_features.size() == torch.Size([1, 10, 768])
+
+# Extract all layer's features (layer 0 is the embedding layer)
+all_layers = camembert.extract_features(tokens, return_all_hiddens=True)
+assert len(all_layers) == 13
+assert torch.all(all_layers[-1] == last_layer_features)
+```
+
+## Citation
+If you use our work, please cite:
+
+```bibtex
+@inproceedings{martin2020camembert,
+  title={CamemBERT: a Tasty French Language Model},
+  author={Martin, Louis and Muller, Benjamin and Su{\'a}rez, Pedro Javier Ortiz and Dupont, Yoann and Romary, Laurent and de la Clergerie, {\'E}ric Villemonte and Seddah, Djam{\'e} and Sagot, Beno{\^\i}t},
+  booktitle={Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics},
+  year={2020}
+}
+```

examples/constrained_decoding/README.md

+# (Vectorized) Lexically constrained decoding with dynamic beam allocation
+
+This page provides instructions for how to use lexically constrained decoding in Fairseq.
+Fairseq implements the code described in the following papers:
+
+* [Fast Lexically Constrained Decoding With Dynamic Beam Allocation](https://www.aclweb.org/anthology/N18-1119/) (Post & Vilar, 2018)
+* [Improved Lexically Constrained Decoding for Translation and Monolingual Rewriting](https://www.aclweb.org/anthology/N19-1090/) (Hu et al., 2019)
+
+## Quick start
+
+Constrained search is enabled by adding the command-line argument `--constraints` to `fairseq-interactive`.
+Constraints are appended to each line of input, separated by tabs. Each constraint (one or more tokens)
+is a separate field.
+
+The following command, using [Fairseq's WMT19 German--English model](https://github.com/pytorch/fairseq/blob/master/examples/wmt19/README.md),
+translates the sentence *Die maschinelle Übersetzung ist schwer zu kontrollieren.* with the constraints
+"hard" and "to influence".
+
+    echo -e "Die maschinelle Übersetzung ist schwer zu kontrollieren.\thard\ttoinfluence" \
+    | normalize.py | tok.py \
+    | fairseq-interactive /path/to/model \
+      --path /path/to/model/model1.pt \
+      --bpe fastbpe \
+      --bpe-codes /path/to/model/bpecodes \
+      --constraints \
+      -s de -t en \
+      --beam 10
+
+(tok.py and normalize.py can be found in the same directory as this README; they are just shortcuts around Fairseq's WMT19 preprocessing).
+This will generate the following output:
+
+    [snip]
+    S-0     Die masch@@ in@@ elle Über@@ setzung ist schwer zu kontrollieren .
+    W-0     1.844   seconds
+    C-0     hard
+    C-0     influence
+    H-0     -1.5333266258239746     Mach@@ ine trans@@ lation is hard to influence .
+    D-0     -1.5333266258239746     Machine translation is hard to influence .
+    P-0     -0.5434 -0.1423 -0.1930 -0.1415 -0.2346 -1.8031 -0.1701 -11.7727 -0.1815 -0.1511
+
+By default, constraints are generated in the order supplied, with any number (zero or more) of tokens generated
+between constraints. If you wish for the decoder to order the constraints, then use `--constraints unordered`.
+Note that you may want to use a larger beam.
+
+## Implementation details
+
+The heart of the implementation is in `fairseq/search.py`, which adds a `LexicallyConstrainedBeamSearch` instance.
+This instance of beam search tracks the progress of each hypothesis in the beam through the set of constraints
+provided for each input sentence. It does this using one of two classes, both found in `fairseq/token_generation_contstraints.py`:
+
+* OrderedConstraintState: assumes the `C` input constraints will be generated in the provided order
+* UnorderedConstraintState: tries to apply `C` (phrasal) constraints in all `C!` orders
+
+## Differences from Sockeye
+
+There are a number of [differences from Sockeye's implementation](https://awslabs.github.io/sockeye/inference.html#lexical-constraints).
+
+* Generating constraints in the order supplied (the default option here) is not available in Sockeye.
+* Due to an improved beam allocation method, there is no need to prune the beam.
+* Again due to better allocation, beam sizes as low as 10 or even 5 are often sufficient.
+* [The vector extensions described in Hu et al.](https://github.com/edwardjhu/sockeye/tree/trie_constraints) (NAACL 2019) were never merged
+  into the main Sockeye branch.
+
+## Citation
+
+The paper first describing lexical constraints for seq2seq decoding is:
+
+```bibtex
+@inproceedings{hokamp-liu-2017-lexically,
+  title = "Lexically Constrained Decoding for Sequence Generation Using Grid Beam Search",
+  author = "Hokamp, Chris  and
+    Liu, Qun",
+  booktitle = "Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)",
+  month = jul,
+  year = "2017",
+  address = "Vancouver, Canada",
+  publisher = "Association for Computational Linguistics",
+  url = "https://www.aclweb.org/anthology/P17-1141",
+  doi = "10.18653/v1/P17-1141",
+  pages = "1535--1546",
+}
+```
+
+The fairseq implementation uses the extensions described in
+
+```bibtex
+@inproceedings{post-vilar-2018-fast,
+    title = "Fast Lexically Constrained Decoding with Dynamic Beam Allocation for Neural Machine Translation",
+    author = "Post, Matt  and
+      Vilar, David",
+    booktitle = "Proceedings of the 2018 Conference of the North {A}merican Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long Papers)",
+    month = jun,
+    year = "2018",
+    address = "New Orleans, Louisiana",
+    publisher = "Association for Computational Linguistics",
+    url = "https://www.aclweb.org/anthology/N18-1119",
+    doi = "10.18653/v1/N18-1119",
+    pages = "1314--1324",
+}
+```
+
+and
+
+```bibtex
+@inproceedings{hu-etal-2019-improved,
+  title = "Improved Lexically Constrained Decoding for Translation and Monolingual Rewriting",
+  author = "Hu, J. Edward  and
+    Khayrallah, Huda  and
+    Culkin, Ryan  and
+    Xia, Patrick  and
+    Chen, Tongfei  and
+    Post, Matt  and
+    Van Durme, Benjamin",
+  booktitle = "Proceedings of the 2019 Conference of the North {A}merican Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long and Short Papers)",
+  month = jun,
+  year = "2019",
+  address = "Minneapolis, Minnesota",
+  publisher = "Association for Computational Linguistics",
+  url = "https://www.aclweb.org/anthology/N19-1090",
+  doi = "10.18653/v1/N19-1090",
+  pages = "839--850",
+}
+```

examples/constrained_decoding/normalize.py

+#!/usr/bin/env python3
+#
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+import sys
+
+from sacremoses.normalize import MosesPunctNormalizer
+
+
+def main(args):
+    normalizer = MosesPunctNormalizer(lang=args.lang, penn=args.penn)
+    for line in sys.stdin:
+        print(normalizer.normalize(line.rstrip()), flush=True)
+
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--lang", "-l", default="en")
+    parser.add_argument("--penn", "-p", action="store_true")
+    args = parser.parse_args()
+
+    main(args)

examples/constrained_decoding/tok.py

+#!/usr/bin/env python3
+#
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+import sys
+
+import sacremoses
+
+
+def main(args):
+    """Tokenizes, preserving tabs"""
+    mt = sacremoses.MosesTokenizer(lang=args.lang)
+
+    def tok(s):
+        return mt.tokenize(s, return_str=True)
+
+    for line in sys.stdin:
+        parts = list(map(tok, line.split("\t")))
+        print(*parts, sep="\t", flush=True)
+
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--lang", "-l", default="en")
+    parser.add_argument("--penn", "-p", action="store_true")
+    parser.add_argument("--fields", "-f", help="fields to tokenize")
+    args = parser.parse_args()
+
+    main(args)

examples/conv_seq2seq/README.md

+# Convolutional Sequence to Sequence Learning (Gehring et al., 2017)
+
+## Pre-trained models
+
+Description | Dataset | Model | Test set(s)
+---|---|---|---
+Convolutional <br> ([Gehring et al., 2017](https://arxiv.org/abs/1705.03122)) | [WMT14 English-French](http://statmt.org/wmt14/translation-task.html#Download) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/models/wmt14.v2.en-fr.fconv-py.tar.bz2) | newstest2014: <br> [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/wmt14.v2.en-fr.newstest2014.tar.bz2) <br> newstest2012/2013: <br> [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/wmt14.v2.en-fr.ntst1213.tar.bz2)
+Convolutional <br> ([Gehring et al., 2017](https://arxiv.org/abs/1705.03122)) | [WMT14 English-German](http://statmt.org/wmt14/translation-task.html#Download) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/models/wmt14.en-de.fconv-py.tar.bz2) | newstest2014: <br> [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/wmt14.en-de.newstest2014.tar.bz2)
+Convolutional <br> ([Gehring et al., 2017](https://arxiv.org/abs/1705.03122)) | [WMT17 English-German](http://statmt.org/wmt17/translation-task.html#Download) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/models/wmt17.v2.en-de.fconv-py.tar.bz2) | newstest2014: <br> [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/wmt17.v2.en-de.newstest2014.tar.bz2)
+
+## Example usage
+
+See the [translation README](../translation/README.md) for instructions on reproducing results for WMT'14 En-De and
+WMT'14 En-Fr using the `fconv_wmt_en_de` and `fconv_wmt_en_fr` model architectures.
+
+## Citation
+
+```bibtex
+@inproceedings{gehring2017convs2s,
+  title = {Convolutional Sequence to Sequence Learning},
+  author = {Gehring, Jonas, and Auli, Michael and Grangier, David and Yarats, Denis and Dauphin, Yann N},
+  booktitle = {Proc. of ICML},
+  year = 2017,
+}
+```

examples/criss/README.md

+# Cross-lingual Retrieval for Iterative Self-Supervised Training
+
+https://arxiv.org/pdf/2006.09526.pdf
+
+## Introduction
+
+CRISS is a multilingual sequence-to-sequnce pretraining method where mining and training processes are applied iteratively, improving cross-lingual alignment and translation ability at the same time.
+
+## Unsupervised Machine Translation
+##### 1. Download and decompress CRISS checkpoints
+```
+cd examples/criss
+wget https://dl.fbaipublicfiles.com/fairseq/models/criss/criss_checkpoints.tar.gz
+tar -xf criss_checkpoints.tar.gz
+```
+##### 2. Download and preprocess Flores test dataset
+```
+bash download_and_preprocess_flores_test.sh
+```
+
+##### 3. Run Evaluation on Sinhala-English
+```
+bash unsupervised_mt/eval.sh
+```
+
+## Sentence Retrieval
+##### 1. Download and preprocess Tatoeba dataset
+```
+bash download_and_preprocess_tatoeba.sh
+```
+
+##### 2. Run Sentence Retrieval on Tatoeba Kazakh-English
+```
+bash sentence_retrieval/sentence_retrieval_tatoeba.sh
+```
+
+## Mining
+##### 1. Mine pseudo-parallel
+```
+bash sentence_retrieval/sentence_retrieval_tatoeba.sh
+```
+
+## Citation
+```bibtex
+@article{tran2020cross,
+  title={Cross-lingual retrieval for iterative self-supervised training},
+  author={Tran, Chau and Tang, Yuqing and Li, Xian and Gu, Jiatao},
+  journal={arXiv preprint arXiv:2006.09526},
+  year={2020}
+}
+```

examples/criss/download_and_preprocess_flores_test.sh

+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+
+SPM_ENCODE=flores/scripts/spm_encode.py
+DATA=data_tmp
+SPM_MODEL=criss_checkpoints/sentence.bpe.model
+DICT=criss_checkpoints/dict.txt
+
+download_data() {
+  CORPORA=$1
+  URL=$2
+
+  if [ -f $CORPORA ]; then
+    echo "$CORPORA already exists, skipping download"
+  else
+    echo "Downloading $URL"
+    wget $URL -O $CORPORA --no-check-certificate || rm -f $CORPORA
+    if [ -f $CORPORA ]; then
+      echo "$URL successfully downloaded."
+    else
+      echo "$URL not successfully downloaded."
+      rm -f $CORPORA
+    fi
+  fi
+}
+
+if [[ -f flores ]]; then
+  echo "flores already cloned"
+else
+  git clone https://github.com/facebookresearch/flores
+fi
+
+mkdir -p $DATA
+download_data $DATA/wikipedia_en_ne_si_test_sets.tgz "https://github.com/facebookresearch/flores/raw/master/data/wikipedia_en_ne_si_test_sets.tgz"
+pushd $DATA
+pwd
+tar -vxf wikipedia_en_ne_si_test_sets.tgz
+popd
+
+
+for lang in ne_NP si_LK; do
+  datadir=$DATA/${lang}-en_XX-flores
+  rm -rf $datadir
+  mkdir -p $datadir
+  TEST_PREFIX=$DATA/wikipedia_en_ne_si_test_sets/wikipedia.test
+  python $SPM_ENCODE \
+    --model ${SPM_MODEL} \
+    --output_format=piece \
+    --inputs ${TEST_PREFIX}.${lang:0:2}-en.${lang:0:2} ${TEST_PREFIX}.${lang:0:2}-en.en \
+    --outputs $datadir/test.bpe.${lang}-en_XX.${lang} $datadir/test.bpe.${lang}-en_XX.en_XX
+
+  # binarize data
+  fairseq-preprocess \
+    --source-lang ${lang} --target-lang en_XX \
+    --testpref $datadir/test.bpe.${lang}-en_XX \
+    --destdir $datadir \
+    --srcdict ${DICT} \
+    --joined-dictionary \
+    --workers 4
+done

examples/criss/download_and_preprocess_tatoeba.sh

+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+
+SPM_ENCODE=flores/scripts/spm_encode.py
+DATA=data_tmp
+SPM_MODEL=criss_checkpoints/sentence.bpe.model
+DICT=criss_checkpoints/dict.txt
+
+git clone https://github.com/facebookresearch/LASER
+mkdir -p data_tmp
+declare -A lang_tatoeba_map=( ["ar_AR"]="ara" ["de_DE"]="deu"  ["es_XX"]="spa" ["et_EE"]="est" ["fi_FI"]="fin" ["fr_XX"]="fra" ["hi_IN"]="hin" ["it_IT"]="ita" ["ja_XX"]="jpn" ["ko_KR"]="kor" ["kk_KZ"]="kaz" ["nl_XX"]="nld" ["ru_RU"]="rus" ["tr_TR"]="tur" ["vi_VN"]="vie" ["zh_CN"]="cmn")
+for lang in ar_AR de_DE es_XX et_EE fi_FI fr_XX hi_IN it_IT ja_XX kk_KZ ko_KR nl_XX ru_RU tr_TR vi_VN zh_CN; do
+  lang_tatoeba=${lang_tatoeba_map[$lang]}
+  echo $lang_tatoeba
+  datadir=$DATA/${lang}-en_XX-tatoeba
+  rm -rf $datadir
+  mkdir -p $datadir
+  TEST_PREFIX=LASER/data/tatoeba/v1/tatoeba
+  python $SPM_ENCODE \
+    --model ${SPM_MODEL} \
+    --output_format=piece \
+    --inputs ${TEST_PREFIX}.${lang_tatoeba}-eng.${lang_tatoeba} ${TEST_PREFIX}.${lang_tatoeba}-eng.eng \
+    --outputs $datadir/test.bpe.${lang}-en_XX.${lang} $datadir/test.bpe.${lang}-en_XX.en_XX
+
+  # binarize data
+  fairseq-preprocess \
+    --source-lang ${lang} --target-lang en_XX \
+    --testpref $datadir/test.bpe.${lang}-en_XX \
+    --destdir $datadir \
+    --srcdict ${DICT} \
+    --joined-dictionary \
+    --workers 4
+done

examples/criss/mining/mine.py

+#!/usr/bin/env python3 -u
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+import argparse
+import glob
+from subprocess import check_call
+
+import faiss
+import numpy as np
+
+
+GB = 1024 * 1024 * 1024
+
+
+def call(cmd):
+    print(cmd)
+    check_call(cmd, shell=True)
+
+
+def get_batches(directory, lang, prefix="all_avg_pool"):
+    print(f"Finding in {directory}/{prefix}.{lang}*")
+    files = glob.glob(f"{directory}/{prefix}.{lang}*")
+    emb_files = []
+    txt_files = []
+    for emb_fi in files:
+        emb_files.append(emb_fi)
+        txt_fi = emb_fi.replace(prefix, "sentences")
+        txt_files.append(txt_fi)
+    return emb_files, txt_files
+
+
+def load_batch(emb_file, dim):
+    embeddings = np.fromfile(emb_file, dtype=np.float32)
+    num_rows = int(embeddings.shape[0] / dim)
+    embeddings = embeddings.reshape((num_rows, dim))
+    faiss.normalize_L2(embeddings)
+    return embeddings
+
+
+def knnGPU_sharded(x_batches_f, y_batches_f, dim, k, direction="x2y"):
+    sims = []
+    inds = []
+    xfrom = 0
+    xto = 0
+    for x_batch_f in x_batches_f:
+        yfrom = 0
+        yto = 0
+        x_batch = load_batch(x_batch_f, dim)
+        xto = xfrom + x_batch.shape[0]
+        bsims, binds = [], []
+        for y_batch_f in y_batches_f:
+            y_batch = load_batch(y_batch_f, dim)
+            neighbor_size = min(k, y_batch.shape[0])
+            yto = yfrom + y_batch.shape[0]
+            print("{}-{}  ->  {}-{}".format(xfrom, xto, yfrom, yto))
+            idx = faiss.IndexFlatIP(dim)
+            idx = faiss.index_cpu_to_all_gpus(idx)
+            idx.add(y_batch)
+            bsim, bind = idx.search(x_batch, neighbor_size)
+
+            bsims.append(bsim)
+            binds.append(bind + yfrom)
+            yfrom += y_batch.shape[0]
+            del idx
+            del y_batch
+        bsims = np.concatenate(bsims, axis=1)
+        binds = np.concatenate(binds, axis=1)
+        aux = np.argsort(-bsims, axis=1)
+        sim_batch = np.zeros((x_batch.shape[0], k), dtype=np.float32)
+        ind_batch = np.zeros((x_batch.shape[0], k), dtype=np.int64)
+        for i in range(x_batch.shape[0]):
+            for j in range(k):
+                sim_batch[i, j] = bsims[i, aux[i, j]]
+                ind_batch[i, j] = binds[i, aux[i, j]]
+        sims.append(sim_batch)
+        inds.append(ind_batch)
+        xfrom += x_batch.shape[0]
+        del x_batch
+    sim = np.concatenate(sims, axis=0)
+    ind = np.concatenate(inds, axis=0)
+    return sim, ind
+
+
+def score(sim, fwd_mean, bwd_mean, margin):
+    return margin(sim, (fwd_mean + bwd_mean) / 2)
+
+
+def score_candidates(
+    sim_mat, candidate_inds, fwd_mean, bwd_mean, margin, verbose=False
+):
+    print(" - scoring {:d} candidates".format(sim_mat.shape[0]))
+    scores = np.zeros(candidate_inds.shape)
+    for i in range(scores.shape[0]):
+        for j in range(scores.shape[1]):
+            k = int(candidate_inds[i, j])
+            scores[i, j] = score(sim_mat[i, j], fwd_mean[i], bwd_mean[k], margin)
+    return scores
+
+
+def load_text(files):
+    all_sentences = []
+    for fi in files:
+        with open(fi) as sentence_fi:
+            for line in sentence_fi:
+                all_sentences.append(line.strip())
+    print(f"Read {len(all_sentences)} sentences")
+    return all_sentences
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Mine bitext")
+    parser.add_argument("--src-lang", help="Source language")
+    parser.add_argument("--tgt-lang", help="Target language")
+    parser.add_argument(
+        "--dict-path", help="Path to dictionary file", default="dict.txt"
+    )
+    parser.add_argument(
+        "--spm-path", help="Path to SPM model file", default="sentence.bpe.model"
+    )
+    parser.add_argument("--dim", type=int, default=1024, help="Embedding dimension")
+    parser.add_argument("--mem", type=int, default=5, help="Memory in GB")
+    parser.add_argument("--src-dir", help="Source directory")
+    parser.add_argument("--tgt-dir", help="Target directory")
+    parser.add_argument("--output", help="Output path")
+    parser.add_argument(
+        "--neighborhood", type=int, default=4, help="Embedding dimension"
+    )
+    parser.add_argument(
+        "--threshold", type=float, default=1.06, help="Threshold on mined bitext"
+    )
+    parser.add_argument(
+        "--valid-size",
+        type=int,
+        default=2000,
+        help="Number of sentences used for validation set",
+    )
+    parser.add_argument(
+        "--min-count",
+        type=int,
+        default=50000,
+        help="Min num sentences used for each language",
+    )
+    args = parser.parse_args()
+
+    x_batches_f, x_sents_f = get_batches(args.src_dir, args.src_lang)
+    y_batches_f, y_sents_f = get_batches(args.tgt_dir, args.tgt_lang)
+    margin = lambda a, b: a / b
+    y2x_sim, y2x_ind = knnGPU_sharded(
+        y_batches_f, x_batches_f, args.dim, args.neighborhood, direction="y2x"
+    )
+    x2y_sim, x2y_ind = knnGPU_sharded(
+        x_batches_f, y_batches_f, args.dim, args.neighborhood, direction="x2y"
+    )
+
+    x2y_mean = x2y_sim.mean(axis=1)
+    y2x_mean = y2x_sim.mean(axis=1)
+    fwd_scores = score_candidates(x2y_sim, x2y_ind, x2y_mean, y2x_mean, margin)
+    bwd_scores = score_candidates(y2x_sim, y2x_ind, y2x_mean, x2y_mean, margin)
+    fwd_best = x2y_ind[np.arange(x2y_sim.shape[0]), fwd_scores.argmax(axis=1)]
+    bwd_best = y2x_ind[np.arange(y2x_sim.shape[0]), bwd_scores.argmax(axis=1)]
+    indices = np.stack(
+        (
+            np.concatenate((np.arange(x2y_ind.shape[0]), bwd_best)),
+            np.concatenate((fwd_best, np.arange(y2x_ind.shape[0]))),
+        ),
+        axis=1,
+    )
+    scores = np.concatenate((fwd_scores.max(axis=1), bwd_scores.max(axis=1)))
+
+    x_sentences = load_text(x_sents_f)
+    y_sentences = load_text(y_sents_f)
+
+    threshold = args.threshold
+    min_count = args.min_count
+    seen_src, seen_trg = set(), set()
+    directory = args.output
+    call(f"mkdir -p {directory}")
+    src_out = open(
+        f"{directory}/all.{args.src_lang}",
+        mode="w",
+        encoding="utf-8",
+        errors="surrogateescape",
+    )
+    tgt_out = open(
+        f"{directory}/all.{args.tgt_lang}",
+        mode="w",
+        encoding="utf-8",
+        errors="surrogateescape",
+    )
+    scores_out = open(
+        f"{directory}/all.scores", mode="w", encoding="utf-8", errors="surrogateescape"
+    )
+    count = 0
+    for i in np.argsort(-scores):
+        src_ind, trg_ind = indices[i]
+        if src_ind not in seen_src and trg_ind not in seen_trg:
+            seen_src.add(src_ind)
+            seen_trg.add(trg_ind)
+            if scores[i] > threshold or count < min_count:
+                if x_sentences[src_ind]:
+                    print(scores[i], file=scores_out)
+                    print(x_sentences[src_ind], file=src_out)
+                    print(y_sentences[trg_ind], file=tgt_out)
+                    count += 1
+                else:
+                    print(f"Ignoring sentence: {x_sentences[src_ind]}")
+    src_out.close()
+    tgt_out.close()
+    scores_out.close()
+
+    print(f"Found {count} pairs for threshold={threshold}")
+    with open(f"{directory}/all.{args.src_lang}") as all_s, open(
+        f"{directory}/all.{args.tgt_lang}"
+    ) as all_t, open(f"{directory}/valid.{args.src_lang}", "w") as valid_s, open(
+        f"{directory}/valid.{args.tgt_lang}", "w"
+    ) as valid_t, open(
+        f"{directory}/train.{args.src_lang}", "w"
+    ) as train_s, open(
+        f"{directory}/train.{args.tgt_lang}", "w"
+    ) as train_t:
+        count = 0
+        for s_line, t_line in zip(all_s, all_t):
+            s_line = s_line.split("\t")[1]
+            t_line = t_line.split("\t")[1]
+            if count >= args.valid_size:
+                train_s.write(s_line)
+                train_t.write(t_line)
+            else:
+                valid_s.write(s_line)
+                valid_t.write(t_line)
+                count += 1

examples/criss/mining/mine_example.sh

+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+#
+source_lang=kk_KZ
+target_lang=en_XX
+MODEL=criss_checkpoints/criss.2nd.pt
+SPM=criss_checkpoints/sentence.bpe.model
+SPLIT=test
+LANG_DICT=criss_checkpoints/lang_dict.txt
+SPM_ENCODE=flores/scripts/spm_encode.py
+SAVE_ENCODER=save_encoder.py
+ENCODER_SAVE_ROOT=sentence_embeddings/$MODEL
+DICT=criss_checkpoints/dict.txt
+THRESHOLD=1.02
+MIN_COUNT=500
+
+DATA_DIR=data_tmp
+SAVE_DIR=mining/${source_lang}_${target_lang}_mined
+ENCODER_SAVE_DIR=${ENCODER_SAVE_ROOT}/${source_lang}-${target_lang}
+INPUT_DIR=$DATA_DIR/${source_lang}-${target_lang}-tatoeba
+
+mkdir -p $ENCODER_SAVE_DIR/${target_lang}
+mkdir -p $ENCODER_SAVE_DIR/${source_lang}
+mkdir -p $SAVE_DIR
+
+## Save encoder outputs
+
+# Save encoder outputs for source sentences
+python $SAVE_ENCODER \
+  ${INPUT_DIR} \
+  --path ${MODEL} \
+  --task translation_multi_simple_epoch \
+  --lang-pairs ${source_lang}-${target_lang} \
+  --lang-dict ${LANG_DICT} \
+  --gen-subset ${SPLIT} \
+  --bpe 'sentencepiece' \
+  -s ${source_lang} -t ${target_lang} \
+  --sentencepiece-model ${SPM} \
+  --remove-bpe 'sentencepiece' \
+  --beam 1 \
+  --lang-tok-style mbart \
+  --encoder-save-dir ${ENCODER_SAVE_DIR}/${source_lang}
+
+## Save encoder outputs for target sentences
+python $SAVE_ENCODER \
+  ${INPUT_DIR} \
+  --path ${MODEL} \
+  --lang-pairs ${source_lang}-${target_lang} \
+  --lang-dict ${LANG_DICT} \
+  --task translation_multi_simple_epoch \
+  --gen-subset ${SPLIT} \
+  --bpe 'sentencepiece' \
+  -t ${source_lang} -s ${target_lang} \
+  --sentencepiece-model ${SPM} \
+  --remove-bpe 'sentencepiece' \
+  --beam 1 \
+  --lang-tok-style mbart \
+  --encoder-save-dir ${ENCODER_SAVE_DIR}/${target_lang}
+
+## Mining
+python mining/mine.py \
+  --src-lang ${source_lang} \
+  --tgt-lang ${target_lang} \
+  --dim 1024 \
+  --mem 10 \
+  --neighborhood 4 \
+  --src-dir ${ENCODER_SAVE_DIR}/${source_lang} \
+  --tgt-dir ${ENCODER_SAVE_DIR}/${target_lang} \
+  --output $SAVE_DIR \
+  --threshold ${THRESHOLD} \
+  --min-count ${MIN_COUNT} \
+  --valid-size 100 \
+  --dict-path ${DICT} \
+  --spm-path ${SPM} \
+
+
+## Process and binarize mined data
+python $SPM_ENCODE \
+  --model ${SPM} \
+  --output_format=piece \
+  --inputs mining/${source_lang}_${target_lang}_mined/train.${source_lang} mining/${source_lang}_${target_lang}_mined/train.${target_lang} \
+  --outputs mining/${source_lang}_${target_lang}_mined/train.bpe.${source_lang} mining/${source_lang}_${target_lang}_mined/train.bpe.${target_lang}
+
+python $SPM_ENCODE \
+  --model ${SPM} \
+  --output_format=piece \
+  --inputs mining/${source_lang}_${target_lang}_mined/valid.${source_lang} mining/${source_lang}_${target_lang}_mined/valid.${target_lang} \
+  --outputs mining/${source_lang}_${target_lang}_mined/valid.bpe.${source_lang} mining/${source_lang}_${target_lang}_mined/valid.bpe.${target_lang}
+
+
+fairseq-preprocess \
+  --source-lang ${source_lang} \
+  --target-lang ${target_lang} \
+  --trainpref mining/${source_lang}_${target_lang}_mined/train.bpe \
+  --validpref mining/${source_lang}_${target_lang}_mined/valid.bpe \
+  --destdir mining/${source_lang}_${target_lang}_mined \
+  --srcdict ${DICT} \
+  --joined-dictionary \
+  --workers 8

examples/criss/save_encoder.py

+#!/usr/bin/env python3 -u
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+"""
+Translate pre-processed data with a trained model.
+"""
+
+import numpy as np
+import torch
+from fairseq import checkpoint_utils, options, progress_bar, tasks, utils
+from fairseq.sequence_generator import EnsembleModel
+
+
+def get_avg_pool(
+    models, sample, prefix_tokens, src_dict, remove_bpe, has_langtok=False
+):
+    model = EnsembleModel(models)
+
+    # model.forward normally channels prev_output_tokens into the decoder
+    # separately, but SequenceGenerator directly calls model.encoder
+    encoder_input = {
+        k: v for k, v in sample["net_input"].items() if k != "prev_output_tokens"
+    }
+
+    # compute the encoder output for each beam
+    encoder_outs = model.forward_encoder(encoder_input)
+    np_encoder_outs = encoder_outs[0].encoder_out.cpu().numpy().astype(np.float32)
+    encoder_mask = 1 - encoder_outs[0].encoder_padding_mask.cpu().numpy().astype(
+        np.float32
+    )
+    encoder_mask = np.expand_dims(encoder_mask.T, axis=2)
+    if has_langtok:
+        encoder_mask = encoder_mask[1:, :, :]
+        np_encoder_outs = np_encoder_outs[1, :, :]
+    masked_encoder_outs = encoder_mask * np_encoder_outs
+    avg_pool = (masked_encoder_outs / encoder_mask.sum(axis=0)).sum(axis=0)
+    return avg_pool
+
+
+def main(args):
+    assert args.path is not None, "--path required for generation!"
+    assert (
+        not args.sampling or args.nbest == args.beam
+    ), "--sampling requires --nbest to be equal to --beam"
+    assert (
+        args.replace_unk is None or args.raw_text
+    ), "--replace-unk requires a raw text dataset (--raw-text)"
+
+    args.beam = 1
+    utils.import_user_module(args)
+
+    if args.max_tokens is None:
+        args.max_tokens = 12000
+    print(args)
+    use_cuda = torch.cuda.is_available() and not args.cpu
+
+    # Load dataset splits
+    task = tasks.setup_task(args)
+    task.load_dataset(args.gen_subset)
+
+    # Set dictionaries
+    try:
+        src_dict = getattr(task, "source_dictionary", None)
+    except NotImplementedError:
+        src_dict = None
+    tgt_dict = task.target_dictionary
+
+    # Load ensemble
+    print("| loading model(s) from {}".format(args.path))
+    models, _model_args = checkpoint_utils.load_model_ensemble(
+        args.path.split(":"),
+        arg_overrides=eval(args.model_overrides),
+        task=task,
+    )
+
+    # Optimize ensemble for generation
+    for model in models:
+        model.make_generation_fast_(
+            beamable_mm_beam_size=None if args.no_beamable_mm else args.beam,
+            need_attn=args.print_alignment,
+        )
+        if args.fp16:
+            model.half()
+        if use_cuda:
+            model.cuda()
+
+    # Load alignment dictionary for unknown word replacement
+    # (None if no unknown word replacement, empty if no path to align dictionary)
+    align_dict = utils.load_align_dict(args.replace_unk)
+
+    # Load dataset (possibly sharded)
+    itr = task.get_batch_iterator(
+        dataset=task.dataset(args.gen_subset),
+        max_tokens=args.max_tokens,
+        max_positions=utils.resolve_max_positions(
+            task.max_positions(),
+        ),
+        ignore_invalid_inputs=args.skip_invalid_size_inputs_valid_test,
+        required_batch_size_multiple=args.required_batch_size_multiple,
+        num_shards=args.num_shards,
+        shard_id=args.shard_id,
+        num_workers=args.num_workers,
+    ).next_epoch_itr(shuffle=False)
+
+    num_sentences = 0
+    source_sentences = []
+    shard_id = 0
+    all_avg_pool = None
+    encoder_has_langtok = (
+        hasattr(task.args, "encoder_langtok")
+        and task.args.encoder_langtok is not None
+        and hasattr(task.args, "lang_tok_replacing_bos_eos")
+        and not task.args.lang_tok_replacing_bos_eos
+    )
+    with progress_bar.build_progress_bar(args, itr) as t:
+        for sample in t:
+            if sample is None:
+                print("Skipping None")
+                continue
+            sample = utils.move_to_cuda(sample) if use_cuda else sample
+            if "net_input" not in sample:
+                continue
+
+            prefix_tokens = None
+            if args.prefix_size > 0:
+                prefix_tokens = sample["target"][:, : args.prefix_size]
+
+            with torch.no_grad():
+                avg_pool = get_avg_pool(
+                    models,
+                    sample,
+                    prefix_tokens,
+                    src_dict,
+                    args.remove_bpe,
+                    has_langtok=encoder_has_langtok,
+                )
+                if all_avg_pool is not None:
+                    all_avg_pool = np.concatenate((all_avg_pool, avg_pool))
+                else:
+                    all_avg_pool = avg_pool
+
+            if not isinstance(sample["id"], list):
+                sample_ids = sample["id"].tolist()
+            else:
+                sample_ids = sample["id"]
+            for i, sample_id in enumerate(sample_ids):
+                # Remove padding
+                src_tokens = utils.strip_pad(
+                    sample["net_input"]["src_tokens"][i, :], tgt_dict.pad()
+                )
+
+                # Either retrieve the original sentences or regenerate them from tokens.
+                if align_dict is not None:
+                    src_str = task.dataset(args.gen_subset).src.get_original_text(
+                        sample_id
+                    )
+                else:
+                    if src_dict is not None:
+                        src_str = src_dict.string(src_tokens, args.remove_bpe)
+                    else:
+                        src_str = ""
+
+                if not args.quiet:
+                    if src_dict is not None:
+                        print("S-{}\t{}".format(sample_id, src_str))
+
+                source_sentences.append(f"{sample_id}\t{src_str}")
+
+            num_sentences += sample["nsentences"]
+            if all_avg_pool.shape[0] >= 1000000:
+                with open(
+                    f"{args.encoder_save_dir}/all_avg_pool.{args.source_lang}.{shard_id}",
+                    "w",
+                ) as avg_pool_file:
+                    all_avg_pool.tofile(avg_pool_file)
+                with open(
+                    f"{args.encoder_save_dir}/sentences.{args.source_lang}.{shard_id}",
+                    "w",
+                ) as sentence_file:
+                    sentence_file.writelines(f"{line}\n" for line in source_sentences)
+                all_avg_pool = None
+                source_sentences = []
+                shard_id += 1
+
+    if all_avg_pool is not None:
+        with open(
+            f"{args.encoder_save_dir}/all_avg_pool.{args.source_lang}.{shard_id}", "w"
+        ) as avg_pool_file:
+            all_avg_pool.tofile(avg_pool_file)
+        with open(
+            f"{args.encoder_save_dir}/sentences.{args.source_lang}.{shard_id}", "w"
+        ) as sentence_file:
+            sentence_file.writelines(f"{line}\n" for line in source_sentences)
+    return None
+
+
+def cli_main():
+    parser = options.get_generation_parser()
+    parser.add_argument(
+        "--encoder-save-dir",
+        default="",
+        type=str,
+        metavar="N",
+        help="directory to save encoder outputs",
+    )
+    args = options.parse_args_and_arch(parser)
+    main(args)
+
+
+if __name__ == "__main__":
+    cli_main()

examples/criss/sentence_retrieval/encoder_analysis.py

+#!/usr/bin/env python3 -u
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+import argparse
+import glob
+
+import numpy as np
+
+
+DIM = 1024
+
+
+def compute_dist(source_embs, target_embs, k=5, return_sim_mat=False):
+    target_ids = [tid for tid in target_embs]
+    source_mat = np.stack(source_embs.values(), axis=0)
+    normalized_source_mat = source_mat / np.linalg.norm(
+        source_mat, axis=1, keepdims=True
+    )
+    target_mat = np.stack(target_embs.values(), axis=0)
+    normalized_target_mat = target_mat / np.linalg.norm(
+        target_mat, axis=1, keepdims=True
+    )
+    sim_mat = normalized_source_mat.dot(normalized_target_mat.T)
+    if return_sim_mat:
+        return sim_mat
+    neighbors_map = {}
+    for i, sentence_id in enumerate(source_embs):
+        idx = np.argsort(sim_mat[i, :])[::-1][:k]
+        neighbors_map[sentence_id] = [target_ids[tid] for tid in idx]
+    return neighbors_map
+
+
+def load_embeddings(directory, LANGS):
+    sentence_embeddings = {}
+    sentence_texts = {}
+    for lang in LANGS:
+        sentence_embeddings[lang] = {}
+        sentence_texts[lang] = {}
+        lang_dir = f"{directory}/{lang}"
+        embedding_files = glob.glob(f"{lang_dir}/all_avg_pool.{lang}.*")
+        for embed_file in embedding_files:
+            shard_id = embed_file.split(".")[-1]
+            embeddings = np.fromfile(embed_file, dtype=np.float32)
+            num_rows = embeddings.shape[0] // DIM
+            embeddings = embeddings.reshape((num_rows, DIM))
+
+            with open(f"{lang_dir}/sentences.{lang}.{shard_id}") as sentence_file:
+                for idx, line in enumerate(sentence_file):
+                    sentence_id, sentence = line.strip().split("\t")
+                    sentence_texts[lang][sentence_id] = sentence
+                    sentence_embeddings[lang][sentence_id] = embeddings[idx, :]
+
+    return sentence_embeddings, sentence_texts
+
+
+def compute_accuracy(directory, LANGS):
+    sentence_embeddings, sentence_texts = load_embeddings(directory, LANGS)
+
+    top_1_accuracy = {}
+
+    top1_str = " ".join(LANGS) + "\n"
+    for source_lang in LANGS:
+        top_1_accuracy[source_lang] = {}
+        top1_str += f"{source_lang} "
+        for target_lang in LANGS:
+            top1 = 0
+            top5 = 0
+            neighbors_map = compute_dist(
+                sentence_embeddings[source_lang], sentence_embeddings[target_lang]
+            )
+            for sentence_id, neighbors in neighbors_map.items():
+                if sentence_id == neighbors[0]:
+                    top1 += 1
+                if sentence_id in neighbors[:5]:
+                    top5 += 1
+            n = len(sentence_embeddings[target_lang])
+            top1_str += f"{top1/n} "
+        top1_str += "\n"
+
+    print(top1_str)
+    print(top1_str, file=open(f"{directory}/accuracy", "w"))
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Analyze encoder outputs")
+    parser.add_argument("directory", help="Source language corpus")
+    parser.add_argument("--langs", help="List of langs")
+    args = parser.parse_args()
+    langs = args.langs.split(",")
+    compute_accuracy(args.directory, langs)

examples/criss/sentence_retrieval/sentence_retrieval_tatoeba.sh

+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+#
+source_lang=kk_KZ
+target_lang=en_XX
+MODEL=criss_checkpoints/criss.3rd.pt
+SPM=criss_checkpoints/sentence.bpe.model
+SPLIT=test
+LANG_DICT=criss_checkpoints/lang_dict.txt
+ENCODER_ANALYSIS=sentence_retrieval/encoder_analysis.py
+SAVE_ENCODER=save_encoder.py
+ENCODER_SAVE_ROOT=sentence_embeddings/$MODEL
+
+
+
+DATA_DIR=data_tmp
+INPUT_DIR=$DATA_DIR/${source_lang}-${target_lang}-tatoeba
+ENCODER_SAVE_DIR=${ENCODER_SAVE_ROOT}/${source_lang}-${target_lang}
+mkdir -p $ENCODER_SAVE_DIR/${target_lang}
+mkdir -p $ENCODER_SAVE_DIR/${source_lang}
+
+# Save encoder outputs for source sentences
+python $SAVE_ENCODER \
+  ${INPUT_DIR} \
+  --path ${MODEL} \
+  --task translation_multi_simple_epoch \
+  --lang-dict ${LANG_DICT} \
+  --gen-subset ${SPLIT} \
+  --bpe 'sentencepiece' \
+  --lang-pairs ${source_lang}-${target_lang} \
+  -s ${source_lang} -t ${target_lang} \
+  --sentencepiece-model ${SPM} \
+  --remove-bpe 'sentencepiece' \
+  --beam 1 \
+  --lang-tok-style mbart \
+  --encoder-save-dir ${ENCODER_SAVE_DIR}/${source_lang}
+
+# Save encoder outputs for target sentences
+python $SAVE_ENCODER \
+  ${INPUT_DIR} \
+  --path ${MODEL} \
+  --lang-dict ${LANG_DICT} \
+  --task translation_multi_simple_epoch \
+  --gen-subset ${SPLIT} \
+  --bpe 'sentencepiece' \
+  --lang-pairs ${target_lang}-${source_lang} \
+  -t ${source_lang} -s ${target_lang} \
+  --sentencepiece-model ${SPM} \
+  --remove-bpe 'sentencepiece' \
+  --beam 1 \
+  --lang-tok-style mbart \
+  --encoder-save-dir ${ENCODER_SAVE_DIR}/${target_lang}
+
+# Analyze sentence retrieval accuracy
+python $ENCODER_ANALYSIS --langs "${source_lang},${target_lang}" ${ENCODER_SAVE_DIR}

examples/criss/unsupervised_mt/eval.sh

+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+#
+SRC=si_LK
+TGT=en_XX
+MODEL=criss_checkpoints/criss.3rd.pt
+
+MULTIBLEU=mosesdecoder/scripts/generic/multi-bleu.perl
+MOSES=mosesdecoder
+REPLACE_UNICODE_PUNCT=$MOSES/scripts/tokenizer/replace-unicode-punctuation.perl
+NORM_PUNC=$MOSES/scripts/tokenizer/normalize-punctuation.perl
+REM_NON_PRINT_CHAR=$MOSES/scripts/tokenizer/remove-non-printing-char.perl
+TOKENIZER=$MOSES/scripts/tokenizer/tokenizer.perl
+GEN_TMP_DIR=gen_tmp
+LANG_DICT=criss_checkpoints/lang_dict.txt
+
+if [ ! -d "mosesdecoder" ]; then
+  git clone https://github.com/moses-smt/mosesdecoder
+fi
+mkdir -p $GEN_TMP_DIR
+fairseq-generate data_tmp/${SRC}-${TGT}-flores \
+        --task translation_multi_simple_epoch \
+        --max-tokens 2000 \
+        --path ${MODEL} \
+        --skip-invalid-size-inputs-valid-test \
+        --beam 5 --lenpen 1.0 --gen-subset test  \
+        --remove-bpe=sentencepiece \
+        --source-lang ${SRC} --target-lang ${TGT} \
+        --decoder-langtok --lang-pairs 'en_XX-ar_AR,en_XX-de_DE,en_XX-es_XX,en_XX-fr_XX,en_XX-hi_IN,en_XX-it_IT,en_XX-ja_XX,en_XX-ko_KR,en_XX-nl_XX,en_XX-ru_RU,en_XX-zh_CN,en_XX-tr_TR,en_XX-vi_VN,en_XX-ro_RO,en_XX-my_MM,en_XX-ne_NP,en_XX-si_LK,en_XX-cs_CZ,en_XX-lt_LT,en_XX-kk_KZ,en_XX-gu_IN,en_XX-fi_FI,en_XX-et_EE,en_XX-lv_LV,ar_AR-en_XX,cs_CZ-en_XX,de_DE-en_XX,es_XX-en_XX,et_EE-en_XX,fi_FI-en_XX,fr_XX-en_XX,gu_IN-en_XX,hi_IN-en_XX,it_IT-en_XX,ja_XX-en_XX,kk_KZ-en_XX,ko_KR-en_XX,lt_LT-en_XX,lv_LV-en_XX,my_MM-en_XX,ne_NP-en_XX,nl_XX-en_XX,ro_RO-en_XX,ru_RU-en_XX,si_LK-en_XX,tr_TR-en_XX,vi_VN-en_XX,zh_CN-en_XX,ar_AR-es_XX,es_XX-ar_AR,ar_AR-hi_IN,hi_IN-ar_AR,ar_AR-zh_CN,zh_CN-ar_AR,cs_CZ-es_XX,es_XX-cs_CZ,cs_CZ-hi_IN,hi_IN-cs_CZ,cs_CZ-zh_CN,zh_CN-cs_CZ,de_DE-es_XX,es_XX-de_DE,de_DE-hi_IN,hi_IN-de_DE,de_DE-zh_CN,zh_CN-de_DE,es_XX-hi_IN,hi_IN-es_XX,es_XX-zh_CN,zh_CN-es_XX,et_EE-es_XX,es_XX-et_EE,et_EE-hi_IN,hi_IN-et_EE,et_EE-zh_CN,zh_CN-et_EE,fi_FI-es_XX,es_XX-fi_FI,fi_FI-hi_IN,hi_IN-fi_FI,fi_FI-zh_CN,zh_CN-fi_FI,fr_XX-es_XX,es_XX-fr_XX,fr_XX-hi_IN,hi_IN-fr_XX,fr_XX-zh_CN,zh_CN-fr_XX,gu_IN-es_XX,es_XX-gu_IN,gu_IN-hi_IN,hi_IN-gu_IN,gu_IN-zh_CN,zh_CN-gu_IN,hi_IN-zh_CN,zh_CN-hi_IN,it_IT-es_XX,es_XX-it_IT,it_IT-hi_IN,hi_IN-it_IT,it_IT-zh_CN,zh_CN-it_IT,ja_XX-es_XX,es_XX-ja_XX,ja_XX-hi_IN,hi_IN-ja_XX,ja_XX-zh_CN,zh_CN-ja_XX,kk_KZ-es_XX,es_XX-kk_KZ,kk_KZ-hi_IN,hi_IN-kk_KZ,kk_KZ-zh_CN,zh_CN-kk_KZ,ko_KR-es_XX,es_XX-ko_KR,ko_KR-hi_IN,hi_IN-ko_KR,ko_KR-zh_CN,zh_CN-ko_KR,lt_LT-es_XX,es_XX-lt_LT,lt_LT-hi_IN,hi_IN-lt_LT,lt_LT-zh_CN,zh_CN-lt_LT,lv_LV-es_XX,es_XX-lv_LV,lv_LV-hi_IN,hi_IN-lv_LV,lv_LV-zh_CN,zh_CN-lv_LV,my_MM-es_XX,es_XX-my_MM,my_MM-hi_IN,hi_IN-my_MM,my_MM-zh_CN,zh_CN-my_MM,ne_NP-es_XX,es_XX-ne_NP,ne_NP-hi_IN,hi_IN-ne_NP,ne_NP-zh_CN,zh_CN-ne_NP,nl_XX-es_XX,es_XX-nl_XX,nl_XX-hi_IN,hi_IN-nl_XX,nl_XX-zh_CN,zh_CN-nl_XX,ro_RO-es_XX,es_XX-ro_RO,ro_RO-hi_IN,hi_IN-ro_RO,ro_RO-zh_CN,zh_CN-ro_RO,ru_RU-es_XX,es_XX-ru_RU,ru_RU-hi_IN,hi_IN-ru_RU,ru_RU-zh_CN,zh_CN-ru_RU,si_LK-es_XX,es_XX-si_LK,si_LK-hi_IN,hi_IN-si_LK,si_LK-zh_CN,zh_CN-si_LK,tr_TR-es_XX,es_XX-tr_TR,tr_TR-hi_IN,hi_IN-tr_TR,tr_TR-zh_CN,zh_CN-tr_TR,vi_VN-es_XX,es_XX-vi_VN,vi_VN-hi_IN,hi_IN-vi_VN,vi_VN-zh_CN,zh_CN-vi_VN' \
+        --lang-dict ${LANG_DICT} --lang-tok-style 'mbart' --sampling-method 'temperature' --sampling-temperature '1.0'  > $GEN_TMP_DIR/${SRC}_${TGT}.gen
+cat $GEN_TMP_DIR/${SRC}_${TGT}.gen | grep -P "^T-" | cut -f2 | $REPLACE_UNICODE_PUNCT | $NORM_PUNC -l ${TGT:0:2} | $REM_NON_PRINT_CHAR | $TOKENIZER -no-escape ${TGT:0:2} > $GEN_TMP_DIR/${SRC}_${TGT}.hyp
+cat $GEN_TMP_DIR/${SRC}_${TGT}.gen | grep -P "^H-" | cut -f3 | $REPLACE_UNICODE_PUNCT | $NORM_PUNC -l ${TGT:0:2} | $REM_NON_PRINT_CHAR | $TOKENIZER -no-escape ${TGT:0:2} > $GEN_TMP_DIR/${SRC}_${TGT}.ref
+${MULTIBLEU} $GEN_TMP_DIR/${SRC}_${TGT}.ref < $GEN_TMP_DIR/${SRC}_${TGT}.hyp

examples/cross_lingual_language_model/README.md

+# Cross-Lingual Language Model Pre-training
+
+Below are some details for training Cross-Lingual Language Models (XLM) - similar to the ones presented in [Lample & Conneau, 2019](https://arxiv.org/pdf/1901.07291.pdf) - in Fairseq. The current implementation only supports the Masked Language Model (MLM) from the paper above.
+
+## Downloading and Tokenizing Monolingual Data
+
+Pointers to the monolingual data from wikipedia, used for training the XLM-style MLM model as well as details on processing (tokenization and BPE) it can be found in the [XLM Github Repository](https://github.com/facebookresearch/XLM#download--preprocess-monolingual-data).
+
+Let's assume the following for the code snippets in later sections to work
+- Processed data is in the folder: monolingual_data/processed
+- Each language has 3 files for train, test and validation. For example we have the following files for English:
+    train.en, valid.en
+- We are training a model for 5 languages: Arabic (ar), German (de), English (en), Hindi (hi) and French (fr)
+- The vocabulary file is monolingual_data/processed/vocab_mlm
+
+
+## Fairseq Pre-processing and Binarization
+
+Pre-process and binarize the data with the MaskedLMDictionary and cross_lingual_lm task
+
+```bash
+# Ensure the output directory exists
+DATA_DIR=monolingual_data/fairseq_processed
+mkdir -p "$DATA_DIR"
+
+for lg in ar de en hi fr
+do
+
+  fairseq-preprocess \
+  --task cross_lingual_lm \
+  --srcdict monolingual_data/processed/vocab_mlm \
+  --only-source \
+  --trainpref monolingual_data/processed/train \
+  --validpref monolingual_data/processed/valid \
+  --testpref monolingual_data/processed/test \
+  --destdir monolingual_data/fairseq_processed \
+  --workers 20 \
+  --source-lang $lg
+
+  # Since we only have a source language, the output file has a None for the
+  # target language. Remove this
+
+  for stage in train test valid
+
+    sudo mv "$DATA_DIR/$stage.$lg-None.$lg.bin" "$stage.$lg.bin"
+    sudo mv "$DATA_DIR/$stage.$lg-None.$lg.idx" "$stage.$lg.idx"
+
+  done
+
+done
+```
+
+## Train a Cross-lingual Language Model similar to the XLM MLM model
+
+Use the following command to train the model on 5 languages.
+
+```
+fairseq-train \
+--task cross_lingual_lm monolingual_data/fairseq_processed \
+--save-dir checkpoints/mlm \
+--max-update 2400000 --save-interval 1 --no-epoch-checkpoints \
+--arch xlm_base \
+--optimizer adam --lr-scheduler reduce_lr_on_plateau \
+--lr-shrink 0.5 --lr 0.0001 --min-lr 1e-09 \
+--dropout 0.1 \
+--criterion legacy_masked_lm_loss \
+--max-tokens 2048 --tokens-per-sample 256 --attention-dropout 0.1 \
+--dataset-impl lazy --seed 0 \
+--masked-lm-only \
+--monolingual-langs 'ar,de,en,hi,fr' --num-segment 5 \
+--ddp-backend=no_c10d
+```
+
+Some Notes:
+- Using tokens_per_sample greater than 256 can cause OOM (out-of-memory) issues. Usually since MLM packs in streams of text, this parameter doesn't need much tuning.
+- The Evaluation workflow for computing MLM Perplexity on test data is in progress.
+- Finetuning this model on a downstream task is something which is not currently available.

examples/joint_alignment_translation/README.md

+# Jointly Learning to Align and Translate with Transformer Models (Garg et al., 2019)
+
+This page includes instructions for training models described in [Jointly Learning to Align and Translate with Transformer Models (Garg et al., 2019)](https://arxiv.org/abs/1909.02074).
+
+## Training a joint alignment-translation model on WMT'18 En-De
+
+##### 1. Extract and preprocess the WMT'18 En-De data
+```bash
+./prepare-wmt18en2de_no_norm_no_escape_no_agressive.sh
+```
+
+##### 2. Generate alignments from statistical alignment toolkits e.g. Giza++/FastAlign.
+In this example, we use FastAlign.
+```bash
+git clone git@github.com:clab/fast_align.git
+pushd fast_align
+mkdir build
+cd build
+cmake ..
+make
+popd
+ALIGN=fast_align/build/fast_align
+paste bpe.32k/train.en bpe.32k/train.de | awk -F '\t' '{print $1 " ||| " $2}' > bpe.32k/train.en-de
+$ALIGN -i bpe.32k/train.en-de -d -o -v > bpe.32k/train.align
+```
+
+##### 3. Preprocess the dataset with the above generated alignments.
+```bash
+fairseq-preprocess \
+    --source-lang en --target-lang de \
+    --trainpref bpe.32k/train \
+    --validpref bpe.32k/valid \
+    --testpref bpe.32k/test \
+    --align-suffix align \
+    --destdir binarized/ \
+    --joined-dictionary \
+    --workers 32
+```
+
+##### 4. Train a model
+```bash
+fairseq-train \
+    binarized \
+    --arch transformer_wmt_en_de_big_align --share-all-embeddings \
+    --optimizer adam --adam-betas '(0.9, 0.98)' --clip-norm 0.0 --activation-fn relu\
+    --lr 0.0002 --lr-scheduler inverse_sqrt --warmup-updates 4000 --warmup-init-lr 1e-07 \
+    --dropout 0.3 --attention-dropout 0.1 --weight-decay 0.0 \
+    --max-tokens 3500 --label-smoothing 0.1 \
+    --save-dir ./checkpoints --log-interval 1000 --max-update 60000 \
+    --keep-interval-updates -1 --save-interval-updates 0 \
+    --load-alignments --criterion label_smoothed_cross_entropy_with_alignment \
+    --fp16
+```
+
+Note that the `--fp16` flag requires you have CUDA 9.1 or greater and a Volta GPU or newer.
+
+If you want to train the above model with big batches (assuming your machine has 8 GPUs):
+- add `--update-freq 8` to simulate training on 8x8=64 GPUs
+- increase the learning rate; 0.0007 works well for big batches
+
+##### 5. Evaluate and generate the alignments (BPE level)
+```bash
+fairseq-generate \
+    binarized --gen-subset test --print-alignment \
+    --source-lang en --target-lang de \
+    --path checkpoints/checkpoint_best.pt --beam 5 --nbest 1
+```
+
+##### 6. Other resources.
+The code for:
+1. preparing alignment test sets
+2. converting BPE level alignments to token level alignments
+3. symmetrizing bidirectional alignments
+4. evaluating alignments using AER metric
+can be found [here](https://github.com/lilt/alignment-scripts)
+
+## Citation
+
+```bibtex
+@inproceedings{garg2019jointly,
+  title = {Jointly Learning to Align and Translate with Transformer Models},
+  author = {Garg, Sarthak and Peitz, Stephan and Nallasamy, Udhyakumar and Paulik, Matthias},
+  booktitle = {Conference on Empirical Methods in Natural Language Processing (EMNLP)},
+  address = {Hong Kong},
+  month = {November},
+  url = {https://arxiv.org/abs/1909.02074},
+  year = {2019},
+}
+```