* in NPU environment, use CPUPlace for missing operators.

* in NPU environment, use CPUPlace for missing operators.

* fix TensorCopy bug and add unit test.

* fix code style.

* add more unit tests.

* - fix to #33282

* - Increased threshold for elementwise_mul_bf16 grad

* -disabled faulty UT

* - fix to approval

* tmp

* pass con_element_add2_act

* recover unittests CMakeLists

* init pass enhance

* fix the attr according to review

* repair the attr conv2d

* repair axis of elementwise_add

* CI-coverage test=allcase

* repari some attr

* recover batch_norm_act

* conv_elementwise_add2_act_fuse

* base changes for split op

* 90% of split functionality added

* full fp32 functionality

* added bf16 test

* added submemory caching

* added bf test to static mode whitelist

* minor change

* enabled split op for inference

* minor fix

* minor fix

* optimize attr default value, test=develop

* refine, test=develop

* refine, test=develop

* refine, test=develop

* fix bug in AttrReader, test=develop

* fix bug, test=develop

* fix double_grad, test=develop

* refine, test=develop

* refine, test=develop

* fix checker null, test=develop

* for test, test=develop

* refine, test=develop

* refine, test=develop

* refine, test=develop

* refine, test=develop

* refine, test=develop

* refine, test=develop

* enable npu alignment

* support flatten_params/grads

* support clip by global norm

* remove memset in coalesce_tensor_op

* fix npu kernel of sum op when input is one tensor

* add ut for flatten_param_grads+regularizer

* fix ut

* fix typo

* batch_norm_act_fuse_pass_init

* repair the unittest of batch_norm_act

* simplify_with_basic

* fix

* scale factor

* new api trunc, test=develop

* Small changes related to BF16 fusion_gru and fusion_lstm

* Correct to pass arg by value

* Add conditions to rnn op

* Correct the spelling mistake

* Improving the test with checking activation

* Trigger CI

* fc_elementwise_layer_fuse_pass

* fc_ele_layernorm_pass

* fc_elementwise_layernorm_pass

* fc_elementwise_layernorm_pass_amend

* add check nan of inf for dygraph

* add unittest for dygraph

* revert error change

* support state_dict save to memory.

* Perfect unittest

* perfect unittest.

* suport saving binary var to memory

* polish code.

* packag save/load files into pybind/io.py

* polish code .

* add example for save to memory; remove useless save load function(_load_static_dict,_save_dygraph_dict)

* delete _load_static/dygraph_dict;_save_static/dygraph_dict

* edit example of paddle.save/load

* fix inference prepare data bug

* rename functions

* typo

* typo

* typo

* UT correct

* correct condition

* correct condition

* ci coverage

* morelines

* fix ci coverage