From 23edebc0797008f0525fd1eef7f1299b513457ad Mon Sep 17 00:00:00 2001
From: VictorSanh <victorsanh@gmail.com>
Date: Wed, 2 Oct 2019 11:01:33 -0400
Subject: [PATCH] update extract_distilbert

---
 ...ct_for_distil.py => extract_distilbert.py} | 28 +++++++------------
 1 file changed, 10 insertions(+), 18 deletions(-)
 rename examples/distillation/scripts/{extract_for_distil.py => extract_distilbert.py} (76%)

diff --git a/examples/distillation/scripts/extract_for_distil.py b/examples/distillation/scripts/extract_distilbert.py
similarity index 76%
rename from examples/distillation/scripts/extract_for_distil.py
rename to examples/distillation/scripts/extract_distilbert.py
index 2e7e5c73d8..fdb0662ca7 100644
--- a/examples/distillation/scripts/extract_for_distil.py
+++ b/examples/distillation/scripts/extract_distilbert.py
@@ -14,6 +14,7 @@
 # limitations under the License.
 """
 Preprocessing script before training DistilBERT.
+Specific to BERT -> DistilBERT.
 """
 from transformers import BertForMaskedLM, RobertaForMaskedLM
 import torch
@@ -21,7 +22,7 @@ import argparse
 
 if __name__ == '__main__':
     parser = argparse.ArgumentParser(description="Extraction some layers of the full BertForMaskedLM or RObertaForMaskedLM for Transfer Learned Distillation")
-    parser.add_argument("--model_type", default="bert", choices=["bert", "roberta"])
+    parser.add_argument("--model_type", default="bert", choices=["bert"])
     parser.add_argument("--model_name", default='bert-base-uncased', type=str)
     parser.add_argument("--dump_checkpoint", default='serialization_dir/tf_bert-base-uncased_0247911.pth', type=str)
     parser.add_argument("--vocab_transform", action='store_true')
@@ -31,9 +32,8 @@ if __name__ == '__main__':
     if args.model_type == 'bert':
         model = BertForMaskedLM.from_pretrained(args.model_name)
         prefix = 'bert'
-    elif args.model_type == 'roberta':
-        model = RobertaForMaskedLM.from_pretrained(args.model_name)
-        prefix = 'roberta'
+    else:
+        raise ValueError(f'args.model_type should be "bert".')
 
     state_dict = model.state_dict()
     compressed_sd = {}
@@ -68,20 +68,12 @@ if __name__ == '__main__':
                 state_dict[f'{prefix}.encoder.layer.{teacher_idx}.output.LayerNorm.{w}']
         std_idx += 1
 
-    if args.model_type == 'bert':
-        compressed_sd[f'vocab_projector.weight'] = state_dict[f'cls.predictions.decoder.weight']
-        compressed_sd[f'vocab_projector.bias'] = state_dict[f'cls.predictions.bias']
-        if args.vocab_transform:
-            for w in ['weight', 'bias']:
-                compressed_sd[f'vocab_transform.{w}'] = state_dict[f'cls.predictions.transform.dense.{w}']
-                compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'cls.predictions.transform.LayerNorm.{w}']
-    elif args.model_type == 'roberta':
-        compressed_sd[f'vocab_projector.weight'] = state_dict[f'lm_head.decoder.weight']
-        compressed_sd[f'vocab_projector.bias'] = state_dict[f'lm_head.bias']
-        if args.vocab_transform:
-            for w in ['weight', 'bias']:
-                compressed_sd[f'vocab_transform.{w}'] = state_dict[f'lm_head.dense.{w}']
-                compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'lm_head.layer_norm.{w}']
+    compressed_sd[f'vocab_projector.weight'] = state_dict[f'cls.predictions.decoder.weight']
+    compressed_sd[f'vocab_projector.bias'] = state_dict[f'cls.predictions.bias']
+    if args.vocab_transform:
+        for w in ['weight', 'bias']:
+            compressed_sd[f'vocab_transform.{w}'] = state_dict[f'cls.predictions.transform.dense.{w}']
+            compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'cls.predictions.transform.LayerNorm.{w}']
 
     print(f'N layers selected for distillation: {std_idx}')
     print(f'Number of params transfered for distillation: {len(compressed_sd.keys())}')