* Add cholesky_op forward part. test=develop

* Complete cholesky_op forward part. test=develop

* Add cholesky_op backward part. test=develop

* Complete cholesky_op backward part. test=develop

* Refine cholesky_op error check and docs. test=develop

* Add grad_check unit test for cholesky_op. test=develop

* Fix sample code in cholesky doc. test=develop

* Refine some error messages of cholesky_op. test=develop

* Refine some error messages of cholesky_op. test=develop

* Remove unused input in cholesky_grad. test=develop

* Remove unused input in cholesky_grad. test=develop

* Fix stream for cusolverDnSetStream. test=develop

* Update PADDLE_ENFORCE_CUDA_SUCCESS from cholesky_op to adapt to latest code.
test=develop

* Add CUSOLVER ERROR in enforce.h
test=develop

* Fix the missing return value in cholesky. test=develop

* add the thread_local_allocator, test=develop

* refactor the thread_local_allocator, test=develop

* provides option setting strategy, test=develop

* Optimize the error messages of paddle CUDA API, test=develop

* fix the error messages of paddle CUDA API, test=develop

* Refactoring PADDLE_ENFORCE_CUDA_SUCCESS, and apply to curand/cudnn/cublas/NCCL,test=develop

* remove build_ex_string,test=develop

* merge conflict,test=develop

* update eigen, test=develop

* remove patches, test=develop

* add definition of -fabi-version, test=develop

* add patch for TensorBlock.h, test=develop

* test windows, test=develop

* only update eigen for Linux, test=develop

* add code comments, test=develop

* supports thread-binding stream, test=develop

* avoid using thread_local variables in dtor, test=develop

* modify the stream priority enum, test=develop

Correct the name [`FLAGS_sync_nccl_allreduce`](https://www.paddlepaddle.org.cn/documentation/docs/zh/advanced_guide/flags/others_cn.html#flags-sync-nccl-allreduce) based on the information from our official website.

eagerly release cuda resources before cuda enviroment destroying
test=develop

* Initial FP32 DNNL MatMul Implementation

* Implement int8 DNNL MatMul

* Unify in-kernel-naming, clean UTs

* MatmuL: Introduce op caching

* Final adjustments

test=develop

* Remove dy_graph disablement

test=develop

* Change dnnl header name to new one

test=develop

* Contrain multi head check to prevent fails

test=develop

* Resolve dnnl header problems on MAC CI

* Variable namings to kernel and skip_grad_ci added

test=develop

* Prevent MAC CI from failing

* Prevent windows build from failing

test=develop

* Modify UTs to conform to the rules

* Modify MatMul aux functions namings

test=develop

add addmm op

* Remove the NGraph engine from PDPD repository
1. Each operator was removed from the operator's directory
2. Each test was removed from the unittest directory
3. The parallel executor support was removed from the PDPD
4. The CMake file was removed from the PDPD
5. The NG flags were removed from the repository
test=develop

* Remove ngraph from:
1. Cmake file
2. Python file
test=develop

* delete invalid check inferface Ref & VectorRef, test=develop

* fix vector ref delete error, test=develop

* try the new check inferface, test=develop

* change all related code with new check macro, test=develop

* remove static assert, test=develop

* polish detail, test=develop

* skip coverage problem, test=develop

* add new check macro, test=develop

* fix init_gflags with 'python -c', test=develop

* add test, test=develop

* use sys.executable instead of python, test=develop

* keep dummy, test=develop

* add op inout check macro, test=develop

* fix enforce_test, test=develop

* Delete is_test from activation operators
test=develop

* Revent unneeded changes
test=develop

As nccl comm is not created by CUDADeviceContext, it should be destroyed by the creator as the best practice of RAII.

* refine output of profiler for child event 

initialize global nccl context in dygraph
test=develop

* refine the profiler print test=develop

* add recorded cuda memory apis, fix typo, test=develop

* add more ut, test=develop

* follow comments, test=develop

* fix py35 incompatible issues, test=develop

* add profiler_help.h to refine the code test=develop