* change strided_slice when step<0.

* add unittest for paddle.strided_slice

* polish unittest

* update readme test=document_fix

* update while loop docs test=document_fix

* pass found_inf to adam

* add unittest

* fix bug

* refine unittest

* change unit test's directory

* disable unittest on cpu

* mv recv to head, test=develop

* add cuda event and stream api

* add cuda event and stream api

* add get_current_stream api

* add get_current_stream api

* init streams

* modify get_current_stream

* modify get_cuttent_stream

* add synchronize func

* add current_stream doc and test file

* move get_current_stream into CUDA macro

* move CudaEvent into CUDA macro

* move _get_current_stream and _device_synchronize into cuda macro

* modify the macro of cuda stream and event

* add test case for synchronize

* add paddle.devices.cuda module

* event and stream support hip

* add doc for stream and event class

* move cuda stream and event into single pybind

* add cuda_streams_py.cc to cmakelist

* add _device_synchronize and _get_current_stream to core module

* add test case for cudastream and cudaevent

* move __all__ in streams.py

* fix test fail

* add cuda to devices __all__

* fix current_stream doc writing error

* move devices to device direction, and merge device.py into __init__.py

* add required:gpu to sample codes

* remove cuda direction from device/__init__.py

* fix used before assign

* fix used before assign

* fix func redef

* fix-func-redef

* fix func redef

* fix func redef

* fix func redef

* fix func redef

* fix func redef

* fix func redef

* fix the bug that happened in alltoall in dygraph mode

* [NPU] add sigmoid and sigmoid_cross_entropy_with_logits

* [NPU] add debug logs

* [NPU] delete debug logs

* [NPU] reset to paddle.NPUPlace(0)

* [NPU] add more unittests for sigmoid_cross_entropy_with_logits

* delete useless c++ code, and delete check_dygraph=False

* [NPU] delete repeated codes of unittests

* [NPU] fix licence code style

* [NPU] add attrs (now do not support) check for sigmoid_cross_entropy_with_logits

* add clear_float_status op

* refine infershape

* fix typo

* refine check_finite_and_scale

* refine code

* fix bn

* fix

* add unittest

* fix cpu

* cache core.ops, test=develop

* refine, test=develop

* Refine Constructor logic of ParallelExecutor

* Replace executor into ParallelExecutor in run_program_op

* adam add input SkipUpdate

* add unittest

* add npu unittest

* fix xpu compile

* remove param stream

* jit.save/load support method with parameters.

* add unittest and warning

* polish warning message.

As the title, add Python helper function to get block Inputs/Outputs. This function is helpful to distributed computing for sharding.

* Added OpTestTool for BF16 convenience

* fixes after review, names changed to snake case.

* fixes after review, naming reflects cpu.

* Support sccache to speed up compilation on Windows

* Support sccache to speed up compilation on Windows

* fix paddle.no_grad

* fix paddle.no_grad

* fix undef var

* fix undef var