[Dy2St]Polish visit function in transformer (#44083)

* Polish visit function in transformer

* Call generic_visit first in visit_While/For

* Remove comments

* Polish utils.py, move some transformer to base_transformer

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

@@ -18,10 +18,10 @@ from paddle.utils import gast
 
 from paddle.fluid import unique_name
 from paddle.fluid.dygraph.dygraph_to_static.utils import index_in_list
-from paddle.fluid.dygraph.dygraph_to_static.utils import ForNodeVisitor
 from paddle.fluid.dygraph.dygraph_to_static.utils import BaseNodeVisitor
 from paddle.fluid.dygraph.dygraph_to_static.variable_trans_func import create_bool_node
 from paddle.fluid.dygraph.dygraph_to_static.base_transformer import BaseTransformer
+from paddle.fluid.dygraph.dygraph_to_static.base_transformer import ForNodeVisitor
 
 __all__ = ['BreakContinueTransformer']
 

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

@@ -21,8 +21,8 @@ from paddle.fluid.dygraph.dygraph_to_static.static_analysis import AstNodeWrappe
 from paddle.fluid.dygraph.dygraph_to_static.utils import ast_to_source_code
 from paddle.fluid.dygraph.dygraph_to_static.utils import slice_is_num
 from paddle.fluid.dygraph.dygraph_to_static.utils import is_control_flow_to_transform
-from paddle.fluid.dygraph.dygraph_to_static.utils import SplitAssignTransformer
 from paddle.fluid.dygraph.dygraph_to_static.base_transformer import BaseTransformer
+from paddle.fluid.dygraph.dygraph_to_static.base_transformer import SplitAssignTransformer
 
 
 class ListTransformer(BaseTransformer):

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

@@ -25,14 +25,14 @@ from paddle.fluid.dygraph.dygraph_to_static.static_analysis import StaticAnalysi
 from paddle.fluid.dygraph.dygraph_to_static.utils import ast_to_source_code
 from paddle.fluid.dygraph.dygraph_to_static.utils import generate_name_node
 from paddle.fluid.dygraph.dygraph_to_static.utils import get_attribute_full_name
-from paddle.fluid.dygraph.dygraph_to_static.utils import ForLoopTuplePreTransformer
-from paddle.fluid.dygraph.dygraph_to_static.utils import ForNodeVisitor
-from paddle.fluid.dygraph.dygraph_to_static.utils import RenameTransformer
 from paddle.fluid.dygraph.dygraph_to_static.variable_trans_func import create_undefined_var
 from paddle.fluid.dygraph.dygraph_to_static.variable_trans_func import create_fill_constant_node
 from paddle.fluid.dygraph.dygraph_to_static.utils import create_nonlocal_stmt_nodes, create_get_args_node, create_set_args_node
 from paddle.fluid.dygraph.dygraph_to_static.ifelse_transformer import ARGS_NAME
 from paddle.fluid.dygraph.dygraph_to_static.base_transformer import BaseTransformer
+from paddle.fluid.dygraph.dygraph_to_static.base_transformer import RenameTransformer
+from paddle.fluid.dygraph.dygraph_to_static.base_transformer import ForLoopTuplePreTransformer
+from paddle.fluid.dygraph.dygraph_to_static.base_transformer import ForNodeVisitor
 
 __all__ = ['LoopTransformer', 'NameVisitor']
 
@@ -489,14 +489,15 @@ class LoopTransformer(BaseTransformer):
         self.name_visitor = NameVisitor(self.root)
         self.visit(self.root)
 
-    def visit(self, node):
+    def visit_While(self, node):
         self.generic_visit(node)
-        # All parent nodes that may contain gast.While/gast.For
-        if hasattr(node, 'body'):
-            self.replace_stmt_list(node.body)
-        if hasattr(node, 'orelse'):
-            self.replace_stmt_list(node.orelse)
-        return node
+        new_stmts = self.get_while_stmt_nodes(node)
+        return new_stmts
+
+    def visit_For(self, node):
+        self.generic_visit(node)
+        new_stmts = self.get_for_stmt_nodes(node)
+        return new_stmts
 
     def replace_stmt_list(self, body_list):
         if not isinstance(body_list, list):

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

@@ -20,16 +20,13 @@ import inspect
 from paddle.utils import gast
 from paddle.fluid import core
 from paddle.fluid.dygraph.dygraph_to_static.utils import unwrap
+from paddle.fluid.dygraph.dygraph_to_static.utils import ORIGI_INFO
 from paddle.fluid.framework import Program
 try:
     from collections.abc import Sequence
 except:
     from collections import Sequence
 
-# NOTE(liym27): Please use `getattr(ast_node, ORIGI_INFO)` instead of . operation to get the original information of ast node.
-ORIGI_INFO = "Original information of source code for ast node."
-ORIGI_INFO_MAP = "Original information map of source code."
-
 
 class Location(object):
     """

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

@@ -188,9 +188,7 @@ class ReturnTransformer(BaseTransformer):
         Self-defined visit for appending ancestor
         """
         self.ancestor_nodes.append(node)
-        method = 'visit_' + node.__class__.__name__
-        visitor = getattr(self, method, self.generic_visit)
-        ret = visitor(node)
+        ret = super(ReturnTransformer, self).visit(node)
         self.ancestor_nodes.pop()
         return ret