* Set lod level of sequence_unpad's output to 1 in compile time

* add lod check for sequence op, test=develop

* delete unnecessary check in expend op, test=develop

* Removing last dims constraints of seq_pad and seq_unpad test=develop

* fix test_layer api code test=develop

* fix sequence_pad_op.cc conflict test=develop

* remove test_analyzer_mm_dnn test=develop

* fix vectorize bug test=develop

* fix vectorize<int> test=develop

* support 2-level lod of input in sequence_pool test=develop

* fix lod level bug in .cu test=develop

test=develop

* add topk_avg_pooling

* refine api doc and modify api.spec test=develop

* Add the check of lod in sequence_softmax kernel.
test=develop

* Refine the comments.
test=develop

* sequnce mask support max length tensor input; test=develop

* add rnn_impl.py; test=develop

* add basic gru lstm unittest; test=develop

* fix api spec; test=develop

* fix sequence_mask op bug;
test=develop
test=document_preview

* change +-*x to elmentwise_op; test=develop

* add mkl flag; test=develop

* fix rnn impl bug; test=develop

* update api spec; test=develop

* fix doc bug; test=develop

* fix lstm bugs; test=develop

* Use TensorCopySync for sequence_unpad op

test=develop

* Fix the tensor memory alloc bug

test=develop

Fix bug in sequence_unpad op, when allocate the output memory do not match actual memory, check memory failed. Fix this bug by allocating the output memeory in correct code position.

* Enable seq_pool op to accept len 0 input

test=develop

* Update sequence_pool's api

test=develop

* Add more unittest cases for seq_pool op

test=develop

* Remove legacy comments

test=develop

* Don't use template in op maker

test=develop

test=develop

* Optimize the computing kernel of sequence_reverse operator.

test=develop

* Clean code

test=develop

* Fix for cpplint syntax checking.

test=develop

* Fix the compile warning issue.

test=develop

* Support seq len equal to 0 in sequence ops

test=develop

* Add more test cases

* Fix some comments

test=develop

* Fix py3 error

test=develop

* fix overflow by int32 mul test=develop

* fix reference nullptr

* fix codestyle test=develop

* modify to point in ContextProjectFunctor test=develop

* modify to point in ContextProjectFunctor test=develop

* modify . to -> test=develop

test=develop

test=develop

test=develop

test=develop

test=develop

test=develop

test=develop

test=develop

test=develop

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test=develop

Optimize the CUDA implementation of sequence_expand op by reduce the times of copying lod data from CPU to GPU. (#15493)

* Optimize the CUDA implementation of sequence_expand op by reduce the times of copying lod data from CPU to GPU.
test=develop

* Refine the op benchmark to support setting lod in config.
test=develop

* fix warnings

test=develop

* fix enforce test

test=develop

* Add check of input in sequence_expand op.
test=develop

* Correct the unittest of sequence_expand op.
test=develop

* code style fix, test=develop

test=develop

test=develop

The macro should be defined by compiler rather than by source.

test=develop

test=develop

* wip simplify operator framework

* wip

* wip

* done test=develop

* clean test=develop

* fix test=develop

* fix deps test=develop

* fix cpu build test=develop

* fix tensorrt build test=develop

* fix tests test=develop

* fix test=develop

* fix cpu build test=develop