* support refuse forward dygraph

* modify backward api exponential__grad yaml

* remove print code

* 当反向复用前向时进行需不需要更高阶的反向判断，如果不需要调用c++ api，需要的话则调用前向动态图生成反向节点

* fix some backward bugs

* modify the generated dygraph function name

* add legacy_api.yaml

* set merged_momentum inplace only

* support inplace optional<vector<tensor>>

* add dygraph_mode api

* optimize TensorToConstDenseTensorPtr

* [Eager draft] forward_only interface migrate to autograd_api

* strings api add dygraph forward function

* rm useless comments

* draft version for check CI

* fix ci

* forward-only no need compute_require_grad and pass stop_gradient, rm useless comments

* polish yaml and using CPUPlace = phi::CPUPlace

* rm useless comments

* polish yaml and update some test case

* rm useless funcs

* polish eager_gen code

* polish code

* support optional<vector<Tensor>> in yaml and eager

* delete useless comments in eager_gen.py

* fix api_base.py support optional<vector<TTensor>>

* python_c_gen.py support optional<vector<tensor>>

* transfer linear_interp_v2 yaml from fluid to phi

* fix op_test typo error

* change linear_interp_v2 testcase

* fix args in final_state_linear_interp_v2

* fix zeropad2d typo. test=document_fix

* Polish black_ops_list logic in eager_gen

* update black_ops_list

* fix deriv with inplace

* fix double grad bugs

* remove additional file

* fix compat dygraph mode

* fix yaml remove additional yaml

* fix slice double grad error and auto code gen logic error for higher order differentiate

* fix fix_higher_order_deriv

* remove additional include

* fix fix_higher_order_deriv

* fix starganv2

* fix starganv2 stop_gradient end error

* fix edvr_starganv2

* fix mul kernel to fix optional ddx

* fix typo

* add yaml

* fix infrt compile bugs

* refactor the optional tensor

* remove optiona<MetaTensor> in InferMeta

* fix bug

* fix optional<vector<Tensor>>

* fix bug

* fix rmsprop

* fix amp of eager_gen

* polish code

* fix deleted code

* fix merge conflict

* polish code

* remove is_nullopt_

* fix merge conflict

* fix merge conflict

* add assign_out_ yaml

* fix final_state_assign

* fix inplace bug

* add inplace_check_blacklist for assign

* fix merge conflict

* support inplace in backward

* fix final_state_linear

* fix format of backward_inplace_map

* little change

* add subtract in yaml

* fix hook mem leak

* fix hook use_count

* little format change

* fix
Co-authored-by: NJiabinYang <360788950@qq.com>

* 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

* fix bug of higher order derivative

* fix bug of FillZeroForEmptyGradInput

* remove redundant vector in grad_node

* fix bug of test_deformable_conv_v1_op

* fix bug of test_deformable_conv_v1_op

* some refacotr

* [Eager] Polish eager code generation

* Remove useless code in codegen

* add nan_inf_utils for eager

* support check nan and inf

* add unittest for coverage

* update code

* change the return type for inplace dygraph api

* change the tuple construct

* remove full reserved strategy

* fix inplace error

* 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 Gradient Accumulation for sr

* add ut

* change ut to fit small vector

* polish code details

* remove needless prefix

* revert needless change

* polish grad func generated format

* fix new dygraph record event

* refine name

* fix

* fix

* fix according to review

* [DoubleGrad] Enabled double grad test cases in eager_mode for test_imperative_double_grad

* Fixed elementwise issue

* Addressed CI failures

* [DoubleGrad] Enabled test_imperative_triple_grad test cases under eager_mode

* Fixed minor issues

* [DoubleGrad] Enabled double grad test cases in eager_mode for test_imperative_double_grad

* Fixed elementwise issue

* Addressed CI failures

* support final_state in multiprocess

* fix no place.device

* set device_id in eager_gen

* [Refactor] refactored eager_gen.py PR #2

* [DoubleGrad PR #1] Decoupled code generation logics for Dygraph ForwardFunctions and GradNodes

* Fixed minor issue

* Adjusted logics of GenerateNodeCreationCodes and GenerateForwardDefinition

* Fixed issues

* Supported higher-order grad node generation

* [DoubleGrad PR #4] Supported higher-order GradNode generation

* [DoubleGrad #4] Bug Fixes to Double Grad Node Generation

* Fixed yaml typo

* Fixed yaml typo

* fixed minor issues

* [DoubleGrad PR #5] Enabled gradient computations for grad_tensors passed to paddle.grad()

* Fixed minor issue

* Fixed CI-Inference issue

* Fixed CI-inference issues

* [DoubleGrad PR #7] paddle.grad() to copy backward graph before backward run

* Fixed minor issues

* Fixed issue with backward graph construction logic

* Fixed implementation issues with backward graph reconstruction

* Fixed unittest issue

* Fixed issues

* [DoubleGrad PR #8] Enabled triple grads for sigmoid and matmul

* Fixed issues with phi kernel

* Added triple grad test case

* Fixed minor issue

* [Refactor] refactored eager_gen.py PR #2

* [DoubleGrad PR #1] Decoupled code generation logics for Dygraph ForwardFunctions and GradNodes

* Fixed minor issue

* Adjusted logics of GenerateNodeCreationCodes and GenerateForwardDefinition

* Fixed issues

* Supported higher-order grad node generation

* [DoubleGrad PR #4] Supported higher-order GradNode generation

* [DoubleGrad #4] Bug Fixes to Double Grad Node Generation

* Fixed yaml typo

* Fixed yaml typo

* fixed minor issues

* [DoubleGrad PR #5] Enabled gradient computations for grad_tensors passed to paddle.grad()

* Fixed minor issue

* Fixed CI-Inference issue

* Fixed CI-inference issues

* [DoubleGrad PR #7] paddle.grad() to copy backward graph before backward run

* Fixed minor issues

* Fixed issue with backward graph construction logic

* Fixed implementation issues with backward graph reconstruction

* Fixed unittest issue

* Fixed issues

* fix eager gen opti bug

* polish code

* fix some bug

* fix some bugs;

* [Refactor] refactored eager_gen.py PR #2

* [DoubleGrad PR #1] Decoupled code generation logics for Dygraph ForwardFunctions and GradNodes

* Fixed minor issue

* Adjusted logics of GenerateNodeCreationCodes and GenerateForwardDefinition

* Fixed issues

* Supported higher-order grad node generation

* [DoubleGrad PR #4] Supported higher-order GradNode generation

* [DoubleGrad #4] Bug Fixes to Double Grad Node Generation

* Fixed yaml typo

* Fixed yaml typo

* fixed minor issues

* Fixed minor issue