* change the output format of C++ backward api

* fix merge conflict

* fix sparse api code auto-gen

* fix eager_gen bug

* fix bug of output is null

* fix bug of conv2d_grad_impl

* fix optional grad

* fix bug of eager-gen double_grad

* fix bug

* fix multiply_double_grad bug

* remove node pruning

* support setting vector out size in yaml

* support setting size of vector<tensor> for out in yaml

* add roi_align yaml

* fix bug

* rename scalar_array to int_array

* update cmake

* fix conflict

* remove useless log

* refactor code auto-gene for no_need_buffer

* fix some bug

* delete test code

* support intermediate for saprse api

* close intermediate in yaml

* fix dygraph_api dep for eager

* Added more signposts to dygraph profiling

* Fixed minor issues

* Refactored signpost names

* Fixed typo

* Removed debug codes

* Fixed typo

* Adjusted signpost names

* Fixed issues from branch merge

* support code auto-gene for sparse backward api

* fix bug of intermediate api and name of return var

* suppport sparse api in yaml

* support auto-gen code of sparse api

* do some refactor

* add unittest test_sparse_conv_api

* add unitest file
Co-authored-by: Nzkh2016 <zhangkaihuo@baidu.com>

* fix selected_rows bug in C++ API

* add optional for C++ APIO

* data transform support optional

* remove data transform for optional vector<Tensor>

* adjust some format of funtcion

* fix empyt bug

* Support custom implement for C++ API

* rename api_invoke_impl to api_custom_impl

* remove manual_api

* delete mutable_data in copy_to api

* fix problem of copy_to

* add unittest for infer_meta_fn_factory

* fix split cofig in yaml

* fix split cofig in yaml

* modify sum api yaml

* add copy_to wrapped infermeta

* rollback copy impl

* rename pten dir to phi

* rename namespace to phi

* rename infrt pten dir to phi

* resolve conflict

* rename pten to phi in cmake

* revert all infrt change

* change needed files

* fix infrt failed

* fix inference failed

* support inplace and intermediate in yaml

* add cmake for dygraph_api

* add data_transform in pten api

* support GetKernelTypeForVar

* fix complie problem of bfloat16

* add scale_sr in api

* suppport select_row in C++ api

* merge code

* refactor C++ API code-gen

* fix windows problem of C++ API

* add data_transform in pten api

* support GetKernelTypeForVar

* fix complie problem of bfloat16

* change error namespace

* add complex type transform unittest

* fix merge conflict

* change unary infermeta

* change other infermeta

* change all infermeta format

* resolve conflit

* fix test failed

* resolve reshape conflit

* fix compile failed

* adapt auto api gen

* fix reshape failed

* fix concat failed

* resolve conflict

* add config of backward-api auto-gene

* fix compile bug

* remove wrong header

* rename grad_api to backward_api

* modify .gitignore