* [Fix CppExtension Unittest] Change CUDAExtension to CppExtension if necessary

* Temporarily test cpp_extension under GPU

* Split mixed_extension unittest

* add jacobian and hessian in paddle.autograd

* disable unitest 'func_multi_input' for bug in high-order gradient of multiply

* add dimension checks

* add support for 0-D tensor

* change return type from Jacobian to Hessian in hessian function

* refine Jacobian _flatten function for single xs

* refine support for 0-D tensor

* 1. add 'func_multi_input' unitest for multiply_grad_kernel bug fixed
already.
2. support non-inplace math operation via magical method overwriting.

* add unitest for math operation and raise error when 0-D tensor is indexed

* add ndim check on ys and xs according to is_batched, and add one unitest

* refine docstring of jacobian and hessian

* move paddle.incubate.autograd.Jacobian/Hessian to paddle.incubate.autograd.functional.Jacobian/Hessian

* remove single_input unitest case because numerical differentiation is wrong

* remove 3 unitest for numerical result(reference result) is wrong

* 1. rename autodiff.py to autograd.py
2. increase TIMEOUT to 100

* cancel modification for functional Jacobian/Hessian

* 1. use tuple as return type instead of list
2. refine docstring

* add more unitest case to improve coverage

* remove 2 unitest of Hessian for numerical result is wrong

* remove 1 unitest of Hessian for numerical result is wrong

* remove 1 unitest of Hessian for numerical result is wrong

* change unit test to shape check

* correct doc and replace incubate API to stable API in _grad

* modify concat_grad add sum comp rule

* modify opcompat

* updata Adamw.py

out.backward()  -> loss.backward()

* Update adamw.py

* [XPU] remove scale_loss in parallel.py

* [XPU] throw Unimplemented when using Reducer

* add pad op

* add_some_code

* modify some code

* add some code

* add some code

* modify some code

* add some code

* modify some code

* Update composite_backward_api.h

* modify some code

* add some code

* add some code

* add some code

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* polish

* rm paddle_install_dir

* update test=document_fix

* update test=document_fix

* update

* add test

* update

* update

* update

* update

* update

* update

* update

* update

* update

* add todo commont

* add scatter_nd_add comp

* add scatter_nd_add prim

* fix

* fix

* add public_python_api in TestScatterNdAddSimpleOp setup function

* fix composite_backward_api.h

* fix composite_backward

* add test cases

* fix composite_backward_api.h, unittest

* add test cases, test=allcase

* fix test cases, test=allcase

* fix test cases, test=allcase

* assert_allclose, test=allcase

* 1e-5 to 1e-4, test=allcase

* change rtol from 1e-4 to 1e-3, test=allcase

* modify numel in lbfgs and add a new test case. test=develop

* change param 'lr' to 'learning_rate' in lbfgs and its test

* add opt LBFGS and change test

* optimize embedding deterministic mode

* fix compile error

* change FLAGS_cudnn_deterministic to int64

* fix 700 error

* add ut

* fix ut

* fix ut

* fix win32 ci

* fix flags with PHI_DEFINE_EXPORTED_int64

* add leaky relu composite rule

* add public python api

* unset default negative slope

* fix unittest case

* Fix some problems in Paddle english instruction doc files.

* fix some new questions

* fix cn doc problems, test=document_fix

* print modifed flags

* fix ref, opt print

* fix default getter

* fix ut

* add test+conv3d_transpose_part2

* fix some merge error

* fix codestyle

* fix typo

* fix codestyle

* fix some error

* add redef float2uint

* fix conv3d and conv3d_transpose

* fluid clean: remove print/switch from fluid to static

* remove Switch in static.__init__

* fix conflicts.

* replace Switch by case.

* fix piecewise_lr decay.

* fix typo

* fix conflicts.

* fix lr dtype

* keep Switch in paddle.static.nn.control_flow and fix piecewise_lr.

* fix conflicts.

* keep Switch in the fluid.

* fix Switch doc

* fix example in Switch doc

* fix Switch doc.

* fix static/__init__.

* add fp_bf for pool_max_withidx

* fix some error

* fix error

* codestyle error

* fix masktype

* fix input bf type

* input bf dtype convert error

* back to convert input to bf16 first

* fix convert error

* fix bf16 grad check

* rename monkey_patch_varbase as monkey_patch_tensor & monkey_patch_math_varbase as monkey_patch_math_tensor

* rename monkey_patch_varbase as monkey_patch_tensor & monkey_patch_math_varbase as monkey_patch_math_tensor

* rename monkey_patch_varbase as monkey_patch_tensor & monkey_patch_math_varbase as monkey_patch_math_tensor v2

* rename monkey_patch_varbase as monkey_patch_tensor & monkey_patch_math_varbase as monkey_patch_math_tensor fixed bug

* fix bug: wrong match between depend and c_allreduce_sum

* fix codestyle

* fix bug

* add c_sync_calc_stream back

* fix

* revert

* use flag to control

* fix for code coverage

* support 0d tensor for shape and squeeze onednn kernel

* set python api for shape op ut

* add 0D support for trace, test=allcase

* fix trace gpu kernel 0d error, test=allcase

* fix windows error, test=allcase

* remove ASCEND* keyword in doc

* fix PR-CI-Codestyle-Check error

Add paddle.geometric.weighted_sample_neighbors API