[Dynamic-to-Static] Fix bug of convert_logical_and/convert_logical_or: the operands are executed sequentially(#28993)

1) The operands are executed sequentially according to the running logic of Python.
  
  2) If the left hand operand is True(for convert_logical_or)/False(for convert_logical_and), the right hand operand should be executed.

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

@@ -56,25 +56,39 @@ def _run_py_while(cond, body, loop_vars):
     return loop_vars
 
 
-def convert_logical_and(x, y):
+def convert_logical_and(x_func, y_func):
     """
     A function representation of a Python ``and`` statement.
 
     Args:
-        x(bool|Tensor): Left hand operand of ``and`` operator.
-        y(bool|Tensor): Right hand operand of ``and`` operator.
+        x_func(callable): x_func() is the left hand operand of ``and`` operator. x_func() is bool or Tensor.
+        y_func(callable): y_func() is the right hand operand of ``and`` operator.  y_func() is bool or Tensor.
 
     Returns:
         A python bool variable or a bool Tensor.
-    """
 
-    if isinstance(x, Variable) and isinstance(y, Variable):
-        return _run_paddle_logical_and(x, y)
+    NOTE(liym27):
+        1) The operands are executed sequentially according to the running logic of Python. So here the arguments
+        should be callable.
+        2) If the left hand operand is False, the right hand operand should be executed.
+
+        For example:
+            a = x > 1 and y < 1
+        Transformed code:
+            a = paddle.jit.dy2static.convert_logical_and(lambda:x>1, lambda:y<1)
+
+          In `convert_logical_and(lambda:x>1, lambda:y<1)`, `lambda:y<1` must be run after `lambda:x>1`. And
+        if `x>1` is False, `y<1` should NOT be run.
+    """
+    x_value = x_func()
+    if not isinstance(x_value, Variable):
+        return _run_py_logical_and(lambda: x_value, y_func)
 
-    if not isinstance(x, Variable):
-        return _run_py_logical_and(x, y)
+    y_value = y_func()
+    if not isinstance(y_value, Variable):
+        return _run_py_logical_and(lambda: y_value, lambda: x_value)
 
-    return _run_py_logical_and(y, x)
+    return _run_paddle_logical_and(x_value, y_value)
 
 
 def _run_paddle_logical_and(x, y):
@@ -83,31 +97,49 @@ def _run_paddle_logical_and(x, y):
     return logical_and(x, y)
 
 
-def _run_py_logical_and(x, y):
-    assert not isinstance(x, Variable)
-    # NOTE: Returns y if x is True
-    return x and y
+def _run_py_logical_and(x_func, y_func):
+    x_value = x_func()
+    assert not isinstance(x_value, Variable)
+
+    # NOTE(liym27):
+    #  1. Returns y_func() if x_value is False;
+    #  2. If x_value is False, y_func() should not be run.
+    return x_value and y_func()
 
 
-def convert_logical_or(x, y):
+def convert_logical_or(x_func, y_func):
     """
     A function representation of a Python ``or`` statement.
 
     Args:
-        x(bool|Tensor): Left hand operand of ``or`` operator.
-        y(bool|Tensor): Right hand operand of ``or`` operator.
+        x_func(callable): x_func() is the left hand operand of ``or`` operator. x_func() is bool or Tensor.
+        y_func(callable): y_func() is the right hand operand of ``or`` operator.  y_func() is bool or Tensor.
 
     Returns:
         A python bool variable or a bool Tensor.
-    """
 
-    if isinstance(x, Variable) and isinstance(y, Variable):
-        return _run_paddle_logical_or(x, y)
+    NOTE(liym27):
+        1) The operands are executed sequentially according to the running logic of Python. So here the arguments
+        should be callable.
+        2) If the left hand operand is True, the right hand operand should be executed.
 
-    if not isinstance(x, Variable):
-        return _run_py_logical_or(x, y)
+        For example:
+            a = x > 1 or y < 1
+        Transformed code:
+            a = paddle.jit.dy2static.convert_logical_or(lambda:x>1, lambda:y<1)
 
-    return _run_py_logical_or(y, x)
+        In `convert_logical_or(lambda:x>1, lambda:y<1)`, `lambda:y<1` must be run after `lambda:x>1`. And
+        if `x>1` is True, `y<1` should NOT be run.
+    """
+    x_value = x_func()
+    if not isinstance(x_value, Variable):
+        return _run_py_logical_or(lambda: x_value, y_func)
+
+    y_value = y_func()
+    if not isinstance(y_value, Variable):
+        return _run_py_logical_or(lambda: y_value, lambda: x_value)
+
+    return _run_paddle_logical_or(x_value, y_value)
 
 
 def _run_paddle_logical_or(x, y):
@@ -116,10 +148,14 @@ def _run_paddle_logical_or(x, y):
     return logical_or(x, y)
 
 
-def _run_py_logical_or(x, y):
-    assert not isinstance(x, Variable)
-    # NOTE: Returns y if x is False
-    return x or y
+def _run_py_logical_or(x_func, y_func):
+    x_value = x_func()
+    assert not isinstance(x_value, Variable)
+
+    # NOTE(liym27):
+    #  1. Returns y_func() if x_value is False;
+    #  2. If x_value is True, y_func() should not be run.
+    return x_value or y_func()
 
 
 def convert_logical_not(x):
@@ -193,7 +229,6 @@ def _run_paddle_cond(pred, true_fn, false_fn, true_args, false_args,
 
 
 def _run_py_ifelse(pred, true_fn, false_fn, true_args, false_args):
-
     return true_fn(*true_args) if pred else false_fn(*false_args)
 
 

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

@@ -20,7 +20,13 @@ from paddle.fluid.dygraph.dygraph_to_static.utils import ast_to_source_code
 
 class LogicalTransformer(gast.NodeTransformer):
     """
-    Transform python boolean op into Paddle logical op
+    Transform python boolean op into Paddle logical op.
+
+    For example:
+        a = x > 1 and y < 1
+
+    Transformed code:
+        a = paddle.jit.dy2static.convert_logical_and(lambda:x>1, lambda:y<1)
     """
 
     def __init__(self, wrapper_root):
@@ -53,6 +59,12 @@ class LogicalTransformer(gast.NodeTransformer):
         return new_node
 
     def _create_bool_op_node(self, nodes, api_type):
+        '''
+        NOTE(liym27):
+           The arguments of function convert_logical_XX should be callable so that they can be run
+          according to the actual order. In `convert_logical_and(lambda:x>1, lambda:y<1)`, `lambda:y<1`
+          must be run after `lambda:x>1`, If `x>1` is False, `y<1` should NOT be run.
+        '''
         assert len(
             nodes
         ) > 1, "The length of BoolOp should be at least 2, but received {}.".format(
@@ -67,7 +79,7 @@ class LogicalTransformer(gast.NodeTransformer):
             nodes = [pre_logic_node] + [post_logic_node]
 
         args = [ast_to_source_code(child) for child in nodes]
-        new_node_str = "paddle.jit.dy2static.convert_logical_{}(x={}, y={})".format(
+        new_node_str = "paddle.jit.dy2static.convert_logical_{}(lambda:{}, lambda:{})".format(
             api_type, args[0], args[1])
         # NOTE: gast.parse return Module(body=[expr(...)])
         new_node = gast.parse(new_node_str).body[0].value

python/paddle/fluid/tests/unittests/dygraph_to_static/test_logical.py

@@ -0,0 +1,228 @@
+#   Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Tests for logical operators of Dynamic-to-Static.
+Only test simple cases here. The complex test samples like nested ifelse
+or nested loop have been covered in file test_ifelse.py and test_loop.py"""
+from __future__ import print_function
+
+import unittest
+
+import numpy as np
+
+import paddle
+import paddle.fluid as fluid
+from paddle.fluid.dygraph import ProgramTranslator
+
+program_translator = ProgramTranslator()
+
+SEED = 2020
+np.random.seed(22)
+
+
+@paddle.jit.to_static
+def test_logical_not(x):
+    x = paddle.to_tensor(x)
+    if not x:
+        x = x - 1
+    else:
+        x = x + 1
+
+    if x != 10:
+        x = x - 1
+    else:
+        x = x + 1
+
+    y = 0
+    if not y:
+        x = x + 4
+
+    if y != 3:
+        x = x + 2
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_not_2(x):
+    x = paddle.to_tensor(x)
+
+    y = None
+    if y is not None and not y:
+        x = x + 4
+
+    if y != 3:
+        x = x + 2
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_and(x):
+    x = paddle.to_tensor(x)
+
+    if x < 10 and x > 1:
+        x = x - 1
+    else:
+        x = x + 1
+
+    y = 3
+    if y < 10 and y > 1:
+        x = x - 2
+    else:
+        x = x + 2
+
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_and_2(x):
+    x = paddle.to_tensor(x)
+
+    a = None
+    # NOTE(liym27):
+    # because `a is not None` is False, then `a > 1` won't be run,
+    # which means `convert_logical_and(a is not None, a > 1)` should not
+    # run a>1.
+    if a is not None and a > 1:
+        x = x - 1
+    else:
+        x = x + 1
+
+    b = 3
+
+    if b is not None and b > 1:
+        x = x - 1
+    else:
+        x = x + 1
+
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_or(x):
+    x = paddle.to_tensor(x)
+
+    if x < 10 or x > 1:
+        x = x - 1
+    else:
+        x = x + 1
+
+    a = 10
+    if a > 3 or a < 1:
+        x = x - 1
+    else:
+        x = x + 1
+
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_or_2(x):
+    x = paddle.to_tensor(x)
+
+    a = None
+    if x > 1 or a is None or a > 1:
+        x = x - 1
+    else:
+        x = x + 1
+    return x
+
+
+@paddle.jit.to_static
+def test_logical_not_and_or(x):
+    x = paddle.to_tensor(x)
+
+    a = 1
+    if x < 10 and (a < 4 or a > 0) or a < -1 or not x > -1:
+        x = x - 1
+    else:
+        x = x + 1
+    return x
+
+
+class TestLogicalBase(unittest.TestCase):
+    def setUp(self):
+        self.input = np.array([3]).astype('int32')
+        self.place = paddle.CUDAPlace(0) if fluid.is_compiled_with_cuda(
+        ) else paddle.CPUPlace()
+        self._set_test_func()
+
+    def _set_test_func(self):
+        raise NotImplementedError(
+            "Method 'set_test_func' should be implemented.")
+
+    def _run(self, to_static):
+        program_translator.enable(to_static)
+        with fluid.dygraph.guard(self.place):
+            result = self.dygraph_func(self.input)
+            return result.numpy()
+
+    def _run_dygraph(self):
+        return self._run(to_static=False)
+
+    def _run_static(self):
+        return self._run(to_static=True)
+
+
+class TestLogicalNot(TestLogicalBase):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_not
+
+    def test_transformed_result(self):
+        dygraph_res = self._run_dygraph()
+        static_res = self._run_static()
+        self.assertTrue(
+            np.allclose(dygraph_res, static_res),
+            msg='dygraph result is {}\nstatic_result is {}'.format(dygraph_res,
+                                                                   static_res))
+
+
+class TestLogicalNot2(TestLogicalBase):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_not_2
+
+    def test_transformed_result(self):
+        dygraph_res = self._run_dygraph()
+        static_res = self._run_static()
+        self.assertTrue(
+            np.allclose(dygraph_res, static_res),
+            msg='dygraph result is {}\nstatic_result is {}'.format(dygraph_res,
+                                                                   static_res))
+
+
+class TestLogicalAnd(TestLogicalNot):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_and
+
+
+class TestLogicalAnd2(TestLogicalNot):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_and_2
+
+
+class TestLogicalOr(TestLogicalNot):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_or
+
+
+class TestLogicalOr2(TestLogicalNot):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_or_2
+
+
+class TestLogicalNotAndOr(TestLogicalNot):
+    def _set_test_func(self):
+        self.dygraph_func = test_logical_not_and_or
+
+
+if __name__ == '__main__':
+    unittest.main()