!3295 support mix precision in pynative mode

Merge pull request !3295 from wangqiuliang/support-mix-precision

mindspore/nn/cell.py

@@ -26,6 +26,7 @@ from ..common.parameter import Parameter, ParameterTuple
 from .._c_expression import init_backend
 from ..ops.primitive import Primitive
 from ..ops.operations import HookBackward
+from ..ops.functional import cast
 from ..parallel._tensor import _load_tensor_by_layout
 from ..common.tensor import Tensor
 
@@ -60,6 +61,7 @@ class Cell:
     def __init__(self, auto_prefix=True, flags=None):
         self._params = OrderedDict()
         self._cells = OrderedDict()
+        self._params_list = OrderedDict()
         self.training = False
         self.requires_grad = False
         self.pynative = False
@@ -188,11 +190,22 @@ class Cell:
         if '_params' in self.__dict__:
             params = self.__dict__['_params']
             if name in params:
+                if context.get_context("mode") == context.PYNATIVE_MODE:
+                    return self.cast_param(params[name])
                 return params[name]
         if '_cells' in self.__dict__:
             cells = self.__dict__['_cells']
             if name in cells:
                 return cells[name]
+        if context.get_context("mode") == context.PYNATIVE_MODE and '_params_list' in self.__dict__:
+            params_list = self.__dict__['_params_list']
+            if name in params_list:
+                para_list = params_list[name]
+                cast_list = list()
+                for para in para_list:
+                    cast_list.append(self.cast_param(para))
+                para_list = ParameterTuple(cast_list)
+                return para_list
         raise AttributeError("'{}' object has no attribute '{}'.".format(type(self).__name__, name))
 
     def __del__(self):
@@ -225,10 +238,21 @@ class Cell:
                 cell.set_grad(True)
         else:
             _pynative_exec.set_grad_flag(False)
-        if self.enable_hook:
-            output = self._hook_construct(*inputs)
+        cast_inputs = list()
+        if hasattr(self, "_mindspore_flags") and self._mindspore_flags.get('fp16'):
+            for item in inputs:
+                cast_inputs.append(cast(item, mstype.float16))
+        if hasattr(self, "_mindspore_flags") and self._mindspore_flags.get('fp32'):
+            for item in inputs:
+                cast_inputs.append(cast(item, mstype.float32))
+        if cast_inputs:
+            cast_inputs = tuple(cast_inputs)
         else:
-            output = self.construct(*inputs)
+            cast_inputs = inputs
+        if self.enable_hook:
+            output = self._hook_construct(*cast_inputs)
+        else:
+            output = self.construct(*cast_inputs)
         if isinstance(output, Parameter):
             output = output.data
         if self.requires_grad is True:
@@ -241,6 +265,7 @@ class Cell:
     def __setattr__(self, name, value):
         cells = self.__dict__.get('_cells')
         params = self.__dict__.get('_params')
+        params_list = self.__dict__.get('_params_list')
         if isinstance(value, Parameter):
             if params is None:
                 raise AttributeError("Can not assign params before Cell.__init__() call.")
@@ -256,7 +281,12 @@ class Cell:
                 raise AttributeError("Can not assign params before Cell.__init__() call.")
             for item in value:
                 self.insert_param_to_cell(item.name, item, check_name=False)
-            object.__setattr__(self, name, value)
+            if context.get_context("mode") == context.PYNATIVE_MODE:
+                if name in self.__dict__:
+                    del self.__dict__[name]
+                params_list[name] = value
+            else:
+                object.__setattr__(self, name, value)
         elif isinstance(value, Cell):
             if cells is None:
                 raise AttributeError("Can not assign cells before Cell.__init__() call.")
@@ -458,6 +488,19 @@ class Cell:
             raise TypeError("The type of parameter should be 'Parameter' if not None.")
         self._params[param_name] = param
 
+    def cast_param(self, param):
+        """
+        Cast parameter according to auto mix precison level in pynative mode.
+
+        Args:
+            param (Parameter): The parameter to cast.
+        """
+        if hasattr(self, "_mindspore_flags") and self._mindspore_flags.get('fp16'):
+            return cast(param, mstype.float16)
+        if hasattr(self, "_mindspore_flags") and self._mindspore_flags.get('fp32'):
+            return cast(param, mstype.float32)
+        return param
+
     def insert_child_to_cell(self, child_name, child):
         """
         Adds a child cell to the current cell.

tests/st/ops/cpu/test_lstm_op.py

@@ -23,7 +23,7 @@ from mindspore.ops import composite as C
 from mindspore.common.tensor import Tensor
 from mindspore.common.parameter import ParameterTuple, Parameter
 
-context.set_context(device_target='CPU')
+context.set_context(mode=context.GRAPH_MODE, device_target='CPU')
 
 
 class LstmNet(nn.Cell):