Add support for bias is none for fused_attention op.

* skip compiled program with places > 1

* fix corner case and add ut

* fix_nearest

* fix_nearest

* fix_nearest

* fix_nearest

* Added HCCL backend support in dynamic graph mode

* fix segmentation fault

* add ut

* Bug fix for snapshoting VariableWrapper with initialized tensor but empty allocation

* Added unittest for inplace&clear_gradient

* Add transfer_layout/dtype op

* clean useless codes

* fix unused var

* add optest in white.txt

* split into data_transfer.cc

* fix cmake

* modify according reviewer comment

* replace cast_op with transfer_dtype_op

* add isclose op, test=develop

* add isclose op, test=develop

* add isclose api, test=develop

* rm useless code

* rm useless code

* update python api of isclose

* add some unittest of isclose op, test=develop

[Dy2stat]Allow users to switch eval/train mode when using @to_static to decorate a function (#37383)

* Allow users to switch eval/train mode when using @to_static to decorate a function

* refine code for train() and eval()

* support zero dim for slice op

* support zero dim Tensor in set_value op

* polish some debug log

* shape api should not backward

* fix stop_gradient

* update

* update doc

* Removed one ENFORCE statement

* Changed func name to _share_buffer_to

* Improve error reporting information

* Updated the logic of _is_share_buffer_to func

* add new API paddle.nn.initializer.Orthogonal and calculate_gain

* fix comment

* fix comment

* GeneratePass support attr condition and mapping, test=develop

* fix coverage, test=develop

* Add fuse_resnet_unit pass, test=develop

* fix CI errors, test=develop

* fix CI errors, test=develop

* fix unittest error when compiling without CUDA, test=develop

* fix static ci error, test=develop

* limit kernel size must equal 1, test=develop

* add cpu version, using set: sum, min, max

* add cpu version: mean

* improve cpu code and fix dynamic memory allcation problem

* fix arg error, add index judge, delete fp16

* fix bug in CudaAtomicMax and CudaAtomicMin

* add CUDA version

* fix grad_op bug for index

* add op test, add correct cpu grad op

* Add correct CUDA Mean grad

* [Add] Successful MEAN and SUM

* [Add] Successful MIN and MAX in CPU

* [Add] Successful MIN and MAX in CUDA

* fix windows dtype ci

* fix ROCM ci by adding HIP flag

* rename fused_gather_scatter to send_recv

* unify name as send and recv

* change zero index return time

* add send_recv incubate api

* fix index data type, add unittest case for API

* delete redundant input tensor

* fix en example and docs, add default value in pool_type

* add shape judge and max grid judge

* fix comment

* fix index type bug

* add const &

* fix en docs

* delete numpy in examples

* add unittest for int input

* fix send_recv comment

* change send_recv to graph_send_recv

* support `for i in [1,2,3]` statements in dy2stat

* add test case

* fix ci

* remove wrong code

* fix pslib. test=develop

* add device to train_from_dataset. test=develop

* refine fleet.stop_worker. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix executor & ut. test=develop

* fix executor & ut. test=develop

* fix executor & ut. test=develop

* fleet support elastic train

* fleet support elastic train

* support elastic

* add unittest

* fix unitest bug

* fix unittest bug

* fix unittest bug

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix elastic bug

* fix ci fail

* fix ci fail

* fix elastic bug

* fix elastic bug

* fix joint debugging bug

* fix joint debugging bug

* fix windows ci failed

* fix windows ci failed

* Optimize fleet elastic scale in/out

* elastic support pre hook

* add prehook unittest

* Fix the slow running speed of kl_div when option reduction is set

* fix unittest coverage

* init

* add feed ops in python side

* import LRScheduler

* update_feed

* refine code format

* fix. test=develop

* fix. test=develop

* fix. test=develop

* fix. test=develop

* fix. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* refactor heter trainer. test=develop

* fix. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix. test=develop

* fix. test=develop

* fix. test=develop

* fix. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* [Einsum] correct output dimension errors due to single element tensors.

* [Einsum] format polish.

* add

* add BuildOperatorDependences

* fix bug

* add unittest for write after write

* fix merge bug

* fix

* Added BF16 Pool2d grad

* upstream pulled

* fix for CI

* fixes after review

* make pass ut timeout smaller

* increate ut timeout