* fix fetch handler problem and refactor
when a user define FetchHandler class, he or she should initialize a handler
with variable dict. the key of a variable dict is a user defined name,
the value of a variable dict is a Varaible generated from python API.

For each fetching, a user should implement handler function in which
fetched_result_dict will be available and the user can access the fetched value
with user defined keys.

* adapt test_collective_base.py for only two GPU cards available.
test=develop

* fix bug of issue #21259
test=develop

* add int8 kernel to lookup_table op and add dequantize op test=develop

* change paddle_enforce to paddle_enforce_eq test=develop

* change copyright and change some not suitable code test=develop

* remove debug log test=develop

* replace GetInputType with IndicateVarDataType test=develop

* fix EmptyGradMaker test=develop

* fix diff between cpu and gpu test=develop

* use memcopy when int8_t test=develop

Previously, CVM OP was only able to run in CPU. This PR implements its GPU kernel.
What's more, we improve the UTs about CVM OP.

* polish code details, test=develop

* futher polish hint msg, test=develop

* fix fs_client_param bug， user can set this config through fleet_desc_file or fleet config
* test=develop

* open dygraph op test, test=develop

* modify to_variable, test=develop

* modify input and output for dygraph, test=develop

* modify input and output for dygraph(fix bug), test=develop

* fix input processing of dygraph op test, test=develop

* fix bug, test=develop

* fix op test, test=develop

* fix forward bug for dygraph, test=develop

* fix mkldnn op test for forward, test=develop

* update nn.py for dygraph, test=develop

* fix crop_tensor_op, test=develop

* fix elementwise_mul_op, test=develop

* fix fill_op, test=develop

* fix some mkldnn op, test=develop

* open backward op test for dygraph, test=develop

* delete log, test=develop

* close backward op test for dygraph, test=develop

* fix bug for edit_distance_op and test_lstm_cudnn_op, test=develop

* fix optest backward bug for dygraph, test=develop

* fix optest backward bug for dygraph, test=develop

* close backward op test for dygraph, test=develop

* close backward op test for dygraph, test=develop

* open dygraph op test, test=develop

* fix op test for dygraph, fix GradOpDescMaker, test=develop

* fix bug for linear_chain_crf_op.h, test=develop

* remove log, test=develop

* remove log, test=develop

* remove log for op_test.py, test=develop

* remove log for op_test.py, test=develop

* fix bug for var_conv_2d_op, change PADDLE_ENFORCE, test=develop

* fix PADDLE_ENFORCE_EQ for hierarchical_sigmoid_op.cc, test=develop

* fix bug for test_increment_ngraph_op.py, test=develop

* fix lod for op test in dygraph, test=develop

* refactor op_test.py to reduce redundant code, test=develop

* fix lod optest, modify InputVar/OutputVar to HasInput/HasOutput, test=develop

* remove debug log, test=develop

* remove redundant code in base.py, test=develop

* fix some error in optest, test=develop

* fix ClearNoNeedBufferInputs function's bug for LoDTensor, test=develop

* refactor op_test.py, test=develop

* remove redundant writing, test=develop

* fix error(get tensor of the grad variable), test=develop

* fix test_concat_mkldnn test_conv2d_mkldnn, test=develop

* fix optest.py for get tensor of LoDTensor, test=develop

* fix optest.py for get tensor of LoDTensor, test=develop

* fix optest.py for get tensor of LoDTensor, test=develop

* fix some redundant code, test=develop

* reslove conflict and rewrite paddle error message, test=develop

* add input type and input data type check for Print_op test=develop

* add control flow API: case. test=develop

* delete 'raise TypeError' in _error_message() and return a string. test=develop

* polish API document. test=develop

* fix auc drop first commit test=develop

* update datanorm op

* update datanorm with enforce test=develop

* update test=develop

* update format test=develop

* update format

* update format test=develop

* add unit test test=develop

* update unit test test=develop

* update format test=develop

* update format test=develop

* update API description test=develop

* update API description test=develop

* update format test=develop

* fix codes as comments test=develop

* fix description as comments test=develop

* fix description as comments test=develop

* update codes.. test=develop

* fix warnings oof gcc 8 compilation, test=develop

* fix boost::bad_get, test=develop

* refine PADDLE_ENFORCE, test=develop

* add API switch_case. test=develop

add Nest

* modify code according to reviews:
1.Attr(branch_index) support 'uint8' and 'int64' besides 'int32'.
2.remove useless code.
test=develop

* replace fluid.layers.data with fluid.data and polish API document. test=develop

* fix cache table bug
* add save_paddle_inference_model
* fix hdfs util bug
* test=develop

* friendly trace interface, test=develop

* refine TracedLayer, test=develop

* add some docs, test=develop

* add input type and dtype check template, and update some APIs check

* refine check template, and update some APIs check in nn.py

* update some APIs check in loss.py

test=develop

use 2 cards test=develop

* Add Asypadding for conv fusion.

test=develop

reference: pr/20042

* Fix eigen build link error

* Change back file mode

* Use math function & add more checks.

modify the implementation of save_persistables and save_inference_model for fleet collective mode (#20802)

* modify the implementation of  save_persistables and save_inference_model functions for fleet collective, test=develop

* add ut, test=develop

* fix instance norm

* update unitest,test=develop

* set the default value of alpha for prelu to 0.25, test=develop

* add the call to __syncthreads(), test=develop

* fix the implementation of cpu prelu, test=develop

* repair the implementation of element mode prelu, test=develop

* modify test_prelu_op.py, test=develop

* Add the check of lod_level between compile-time and runtime.
test=develop

* Fix bug in check_compile_vs_runtime.
test=develop

* Fix the check of output when it is dispensiable or intermediate.
test=develop

* Share lod of x to out in match_matrix_tensor op in compile-time.

* Implement GetLoDLevel in InferShapeContext.

* Set the default value of check_compile_vs_runtime to False and enable it in test_sequence_pad_op.
test=develop

* Enable check_compile_vs_runtime in test_match_matrix_tensor.

* Add the implementation of SetLoDLevel in InferShapeContext.

* Remove the implementation of IncreaseLoDLevel and call Get/SetLoDLevel instead.

* Remove the implementation of DecreaseLoDLevel and call Set/GetLoDLevel instead.

* Refine some ops and unittests.
test=develop

* Fix a typo.
test=develop

* Remove the check of var type, and change int to int32_t.
test=develop

* Add unittest for Get/SetLoDLevel.
test=develop

* Add transpose2 INT8 for mkl-dnn

test=develop

* Fix test_transpose_int8_mkldnn

test=develop

* Revert "Merge branch 'develop' into transpose_int8_mkldnn_2"

This reverts commit 34011bdb, reversing
changes made to 2ce6473f.

* Revert "Revert "Merge branch 'develop' into transpose_int8_mkldnn_2""

This reverts commit 23754dd7.

* Add template to TransposeMKLDNNHandler

test=develop

* Resolve conflict

test=develop

* Restore get_size and refactor

test=develop

fix bug in pool/conv/conv_transpose: UpdatePaddingAndDilation, _get_padding_with_SAME and conv2dtranspose_forward_naive. (#20997)

* fix bug in pool/conv/conv_transpose:
1. It should be stride[i] not stride[0] in UpdatePaddingAndDilation;
2. fix bug of func  _get_padding_with_SAME in test_conv/conv_transpose_op.py;
3. fix bug of the computation process in function conv2dtranspose_forward_naive.
test=develop

* change test to make the data of different dimensions different. test=develop

* Add asymetric padding support for mkldnn pooling
test=develop

* Add asymetric padding support for mkldnn conv
test=develop

* Add asymetric padding support for mkldnn conv_transpose
test=develop

These ops are useful in control flow.

* fix uniform random; test=develop

* add uniform random test; test=develop