Remove F.softmax_with_cross_entropy in paddlenlp (#484)

* upgrade F.cross_entropy usage

* fix sample code bug

* fix ppl shape error

Author: LiuChiachi

examples/machine_translation/seq2seq/seq2seq_attn.py

@@ -25,8 +25,8 @@ def __init__(self):
         super(CrossEntropyCriterion, self).__init__()
 
     def forward(self, predict, label, trg_mask):
-        cost = F.softmax_with_cross_entropy(
-            logits=predict, label=label, soft_label=False)
+        cost = F.cross_entropy(
+            input=predict, label=label, soft_label=False, reduction='none')
         cost = paddle.squeeze(cost, axis=[2])
         masked_cost = cost * trg_mask
         batch_mean_cost = paddle.mean(masked_cost, axis=[0])

paddlenlp/metrics/perplexity.py

@@ -46,9 +46,10 @@ def __init__(self, name='Perplexity', *args, **kwargs):
         self.total_word_num = 0
 
     def compute(self, pred, label, seq_mask=None):
-        label = paddle.unsqueeze(label, axis=2)
-        ce = F.softmax_with_cross_entropy(
-            logits=pred, label=label, soft_label=False)
+        if label.dim() == 2:
+            label = paddle.unsqueeze(label, axis=2)
+        ce = F.cross_entropy(
+            input=pred, label=label, reduction='none', soft_label=False)
         ce = paddle.squeeze(ce, axis=[2])
         if seq_mask is not None:
             ce = ce * seq_mask

paddlenlp/transformers/bert/modeling.py

@@ -535,9 +535,12 @@ def __init__(self, vocab_size):
     def forward(self, prediction_scores, seq_relationship_score,
                 masked_lm_labels, next_sentence_labels, masked_lm_scale):
         with paddle.static.amp.fp16_guard():
-            masked_lm_loss = paddle.nn.functional.softmax_with_cross_entropy(
-                prediction_scores, masked_lm_labels, ignore_index=-1)
+            masked_lm_loss = F.cross_entropy(
+                prediction_scores,
+                masked_lm_labels,
+                reduction='none',
+                ignore_index=-1)
             masked_lm_loss = masked_lm_loss / masked_lm_scale
-            next_sentence_loss = paddle.nn.functional.softmax_with_cross_entropy(
-                seq_relationship_score, next_sentence_labels)
+            next_sentence_loss = F.cross_entropy(
+                seq_relationship_score, next_sentence_labels, reduction='none')
         return paddle.sum(masked_lm_loss) + paddle.mean(next_sentence_loss)

paddlenlp/transformers/bigbird/modeling.py

@@ -862,14 +862,17 @@ def forward(self, prediction_scores, seq_relationship_score,
                                 masked_lm_scale, masked_lm_weights)
                 print(loss)
         """
-        masked_lm_loss = paddle.nn.functional.softmax_with_cross_entropy(
-            prediction_scores, masked_lm_labels, ignore_index=self.ignore_index)
+        masked_lm_loss = F.cross_entropy(
+            prediction_scores,
+            masked_lm_labels,
+            ignore_index=self.ignore_index,
+            reduction='none')
         masked_lm_loss = paddle.transpose(masked_lm_loss, [1, 0])
         masked_lm_loss = paddle.sum(masked_lm_loss * masked_lm_weights) / (
             paddle.sum(masked_lm_weights) + 1e-5)
         scale = 1.0
         if not self.use_nsp:
             scale = 0.0
-        next_sentence_loss = paddle.nn.functional.softmax_with_cross_entropy(
-            seq_relationship_score, next_sentence_labels)
+        next_sentence_loss = F.cross_entropy(
+            seq_relationship_score, next_sentence_labels, reduction='none')
         return masked_lm_loss + paddle.mean(next_sentence_loss) * scale

paddlenlp/transformers/ernie/modeling.py

@@ -14,6 +14,7 @@
 
 import paddle
 import paddle.nn as nn
+import paddle.nn.functional as F
 
 from .. import PretrainedModel, register_base_model
 
@@ -772,9 +773,12 @@ def __init__(self, vocab_size):
     def forward(self, prediction_scores, seq_relationship_score,
                 masked_lm_labels, next_sentence_labels, masked_lm_scale):
         with paddle.static.amp.fp16_guard():
-            masked_lm_loss = paddle.nn.functional.softmax_with_cross_entropy(
-                prediction_scores, masked_lm_labels, ignore_index=-1)
+            masked_lm_loss = F.cross_entropy(
+                prediction_scores,
+                masked_lm_labels,
+                ignore_index=-1,
+                reduction='none')
             masked_lm_loss = masked_lm_loss / masked_lm_scale
-            next_sentence_loss = paddle.nn.functional.softmax_with_cross_entropy(
-                seq_relationship_score, next_sentence_labels)
+            next_sentence_loss = F.cross_entropy(
+                seq_relationship_score, next_sentence_labels, reduction='none')
             return paddle.sum(masked_lm_loss) + paddle.mean(next_sentence_loss)

paddlenlp/transformers/ernie_gen/modeling.py

@@ -607,7 +607,10 @@ def forward(self, *args, **kwargs):
             if len(tgt_labels.shape) == 1:
                 tgt_labels = paddle.reshape(tgt_labels, [-1, 1])
 
-            loss = paddle.nn.functional.cross_entropy(
-                logits_2d, tgt_labels, soft_label=(tgt_labels.shape[-1] != 1))
+            loss = F.cross_entropy(
+                logits_2d,
+                tgt_labels,
+                reduction="none",
+                soft_label=(tgt_labels.shape[-1] != 1))
 
             return loss, logits_2d, info

paddlenlp/transformers/transformer/modeling.py

@@ -252,7 +252,7 @@ def forward(self, predict, label):
                 label = paddle.randint(
                     low=3,
                     high=vocab_size,
-                    shape=[batch_size, seq_len, vocab_size])
+                    shape=[batch_size, seq_len, 1])
 
                 criterion(predict, label)
         """
@@ -265,9 +265,10 @@ def forward(self, predict, label):
                     x=label, num_classes=predict.shape[-1]),
                 epsilon=self.label_smooth_eps)
 
-        cost = F.softmax_with_cross_entropy(
-            logits=predict,
+        cost = F.cross_entropy(
+            input=predict,
             label=label,
+            reduction='none',
             soft_label=True if self.label_smooth_eps else False)
         weighted_cost = cost * weights
         sum_cost = paddle.sum(weighted_cost)