[PyTorch] [Relay] Add l1 and mse loss function for pytorch frontend (#11978)

* add l1 and mse loss function for pytorch frontend

* fix CI

Author: Yuanjing Shi

python/tvm/relay/frontend/pytorch.py

@@ -932,6 +932,35 @@ def cross_entropy_loss_with_logits(self, inputs, input_types):
         assert weights is None, "weight not supported in cross_entropy_loss"
         return _op.nn.cross_entropy_with_logits(_op.nn.log_softmax(input), target)
 
+    def l1_loss(self, inputs, input_types):
+        assert len(inputs) == 3
+        [predictions, targets, reduction] = inputs
+        delta = _op.abs(_op.subtract(predictions, targets))
+        if reduction == 0:
+            # reduction = "none"
+            return delta
+        elif reduction == 1:
+            # reduction = "mean"
+            return _op.mean(delta)
+        else:
+            # reduction = "sum"
+            return _op.sum(delta)
+
+    def mse_loss(self, inputs, input_types):
+        assert len(inputs) == 3
+        [predictions, targets, reduction] = inputs
+        delta = _op.subtract(predictions, targets)
+        delta = _op.power(delta, _expr.const(2, input_types[0]))
+        if reduction == 0:
+            # reduction = "none"
+            return delta
+        elif reduction == 1:
+            # reduction = "mean"
+            return _op.mean(delta)
+        else:
+            # reduction = "sum"
+            return _op.sum(delta)
+
     def hard_sigmoid(self, inputs, input_types):
         def _relu6(x):
             return _op.tensor.clip(x, 0.0, 6.0)
@@ -3200,7 +3229,6 @@ def create_convert_map(self):
             "aten::silu": self.silu,
             "aten::glu": self.glu,
             "aten::log_sigmoid": self.log_sigmoid,
-            "aten::cross_entropy_loss": self.cross_entropy_loss_with_logits,
             "aten::adaptive_avg_pool1d": functools.partial(
                 self.adaptive_avg_pool, _op.nn.adaptive_avg_pool1d
             ),
@@ -3374,6 +3402,9 @@ def create_convert_map(self):
             "aten::nll_loss": self.nll_loss,
             "aten::nll_loss2d": self.nll_loss,
             "aten::nll_loss_nd": self.nll_loss,
+            "aten::cross_entropy_loss": self.cross_entropy_loss_with_logits,
+            "aten::l1_loss": self.l1_loss,
+            "aten::mse_loss": self.mse_loss,
             "aten::flip": self.flip,
             "aten::gru": self.gru,
             "aten::lstm": self.lstm,

python/tvm/topi/nn/softmax.py

@@ -129,12 +129,12 @@ def log_softmax(x, axis=-1):
     Parameters
     ----------
     data : tvm.te.Tensor
-        2-D input data
+        N-D input data
 
     Returns
     -------
     output : tvm.te.Tensor
-        2-D output with same shape
+        N-D output with same shape
     """
     shape = x.shape
     if axis < 0:

tests/python/frontend/pytorch/test_forward.py

@@ -4177,6 +4177,42 @@ def test_cross_entropy_loss():
     verify_model(torch.nn.CrossEntropyLoss().eval(), input_data=[predictions, targets])
 
 
+def test_forward_l1_loss():
+    torch.set_grad_enabled(False)
+    N, C = 10, 3
+    predictions = torch.rand((N, C)).float()
+    targets = torch.rand((N, C)).float()
+    verify_model(torch.nn.L1Loss().eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.L1Loss(reduction="sum").eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.L1Loss(reduction="none").eval(), input_data=[predictions, targets])
+
+    # multidimension l1 loss
+    d1, d2 = 2, 3
+    predictions = torch.rand((N, C, d1, d2)).float()
+    targets = torch.rand((N, C, d1, d2)).float()
+    verify_model(torch.nn.L1Loss().eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.L1Loss(reduction="sum").eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.L1Loss(reduction="none").eval(), input_data=[predictions, targets])
+
+
+def test_forward_mse_loss():
+    torch.set_grad_enabled(False)
+    N, C = 10, 3
+    predictions = torch.rand((N, C)).float()
+    targets = torch.rand((N, C)).float()
+    verify_model(torch.nn.MSELoss().eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.MSELoss(reduction="sum").eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.MSELoss(reduction="none").eval(), input_data=[predictions, targets])
+
+    # multidimension mse loss
+    d1, d2 = 2, 3
+    predictions = torch.rand((N, C, d1, d2)).float()
+    targets = torch.rand((N, C, d1, d2)).float()
+    verify_model(torch.nn.MSELoss().eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.MSELoss(reduction="sum").eval(), input_data=[predictions, targets])
+    verify_model(torch.nn.MSELoss(reduction="none").eval(), input_data=[predictions, targets])
+
+
 @tvm.testing.uses_gpu
 def test_forward_flip():
     torch.set_grad_enabled(False)