optimize dygraph performance with move runtime import to begining (#37759)

* optimize dygraph probl

* refine code

* fix convert dtype error

* fix import datafeeder error

python/paddle/fluid/data_feeder.py

@@ -93,10 +93,10 @@ def check_type(input, input_name, expected_type, op_name, extra_message=''):
     if in_dygraph_mode():
         return
 
-    from .dygraph.dygraph_to_static.program_translator import in_declarative_mode
     # NOTE: `in_declarative_mode` is used to determined whether this op is called under
     # @declarative in transformation from dygrah to static layer. We add VarBase in
     # expected_type to skip checking because varBase may be created and used in unusual way.
+    from .dygraph.base import in_declarative_mode
     # Need a better design to be fix this.
     if in_declarative_mode():
         if not isinstance(expected_type, tuple):

python/paddle/fluid/dygraph/base.py

@@ -33,6 +33,17 @@ __all__ = [
     'enabled', 'to_variable'
 ]
 
+# Flag that indicates whether running code under `@declarative`
+_in_declarative_mode_ = False
+
+
+def in_declarative_mode():
+    """
+    Return a bool value that indicates whether running code under `@declarative`
+
+    """
+    return _in_declarative_mode_
+
 
 def _switch_to_static_graph_(func):
     def __impl__(*args, **kwargs):
@@ -45,6 +56,16 @@ def _switch_to_static_graph_(func):
 switch_to_static_graph = wrap_decorator(_switch_to_static_graph_)
 
 
+@signature_safe_contextmanager
+def _switch_declarative_mode_guard_(is_declarative=True):
+
+    global _in_declarative_mode_
+    original_val = _in_declarative_mode_
+    _in_declarative_mode_ = is_declarative
+    yield
+    _in_declarative_mode_ = original_val
+
+
 @signature_safe_contextmanager
 def program_desc_tracing_guard(enable):
     tracer = framework._dygraph_tracer()
@@ -63,7 +84,6 @@ _functional_dygraph_context_manager = None
 
 @signature_safe_contextmanager
 def param_guard(parameters):
-    from paddle.fluid.dygraph.dygraph_to_static.program_translator import in_declarative_mode
     # Note: parameters is a reference of self._parameters or self._buffers
     if in_declarative_mode() and not framework.in_dygraph_mode() and parameters:
         origin_parameters = parameters.copy()

python/paddle/fluid/dygraph/dygraph_to_static/program_translator.py

@@ -573,28 +573,6 @@ class StaticFunction(object):
         return self._function_spec
 
 
-# Flag that indicates whether running code under `@declarative`
-_in_declarative_mode_ = False
-
-
-def in_declarative_mode():
-    """
-    Return a bool value that indicates whether running code under `@declarative`
-
-    """
-    return _in_declarative_mode_
-
-
-@signature_safe_contextmanager
-def _switch_declarative_mode_guard_(is_declarative=True):
-
-    global _in_declarative_mode_
-    original_val = _in_declarative_mode_
-    _in_declarative_mode_ = is_declarative
-    yield
-    _in_declarative_mode_ = original_val
-
-
 def _verify_init_in_dynamic_mode(class_instance):
     """
     Verifies the instance is initialized in dynamic mode.
@@ -658,6 +636,7 @@ class ConcreteProgram(object):
         startup_program.random_seed = framework.default_startup_program(
         ).random_seed
 
+        from paddle.fluid.dygraph.base import _switch_declarative_mode_guard_
         with framework.program_guard(main_program, startup_program):
             with _switch_declarative_mode_guard_(is_declarative=True):
                 # 1. Adds `fluid.data` layers for input if needed

python/paddle/fluid/dygraph/layers.py

@@ -31,7 +31,7 @@ from .. import unique_name
 from paddle.fluid import core
 from .layer_object_helper import LayerObjectHelper
 from .layer_hooks import record_program_ops_pre_hook, set_op_customized_attrs_post_hook, LayerOpsRecoder
-from .base import program_desc_tracing_guard, param_guard
+from .base import program_desc_tracing_guard, param_guard, in_declarative_mode
 from paddle.fluid import framework
 from ..param_attr import ParamAttr
 from paddle.fluid.executor import Executor, global_scope
@@ -917,7 +917,6 @@ class Layer(object):
         # In case of ControlFlow, true_fn and false_fn will contain
         # parameters that may not trigger logic of `Operator` to create
         # them. we add this to make sure all parameters is available.
-        from paddle.fluid.dygraph.dygraph_to_static.program_translator import in_declarative_mode
 
         if in_declarative_mode() and not framework.in_dygraph_mode():
             with param_guard(self._parameters), param_guard(self._buffers):