* fix multi-thread error of fc_gru_fuse_pass.cc, test=develop

* export FLAGS and GLOG symbols, test=develop

[Cherry-pick 1.6] fix batch_norm_grad shape=0 & allreduce shape enforce & sync_batch_norm hang in fleet (#22157)

* fix seqconv_eltadd_relu pass during multi-threads predictor, test=develop

* fix attention_lstm_fuse_pass during multi-threads inference, test=develop

* fix embedding_fc_lstm_fuse_pass during multi-threads inference, test=develop

* fix fc_lstm_fuse_pass during multi-threads inference, test=develop

* fix seq_concat_fc_fuse_pass during multi-threads inference, test=develop

This reverts commit 0473cdb8.

make config option DisableGlogInfo() able to mute all inference logs

* fix fetch handler problem and refactor
when a user define FetchHandler class, he or she should initialize a handler
with variable dict. the key of a variable dict is a user defined name,
the value of a variable dict is a Varaible generated from python API.

For each fetching, a user should implement handler function in which
fetched_result_dict will be available and the user can access the fetched value
with user defined keys.

* ADD NV JETSON SUPPORT
test=release/1.6

* CHERRY_PICK: specify the auto growth allocator for inference.
test=release/1.6

* disable reshape inplace in dygraph model; test=develop (#21157)

* fix ExecutionContext::HasInput and ExecutionContext::HasOutput depend on the scope structure, test=develop (#20721)

* support dump param of model into afs (#20302)

* support dump param to afs
test=develop

* code style
test=develop

* code style
test=develop

* dump param
test=develop

* dump param
test=develop

* dump param
test=develop

* dump param
test=develop

* find lookup table in order (#20932)

test=develop

* cherry-pick
test=develop

* solve pslib core in stop worker
test=develop

* print table stat info for pslib
test=develop

* fix cache table bug, add save_paddle_inference_model, fix hdfs util bug (#21052)

* fix cache table bug
* add save_paddle_inference_model
* fix hdfs util bug
* test=develop

* fix several sparse table issuses (#20686)

* no longer need to define all embedding layers (no one less) of all slots in each program. make trainer_param repeated in ps.proto.
* add find_distributed_lookup_table_grads instead of hard code GRAD
* support embedding stop gradient. push sparse has error before fix this.* 
* fix fill sparse, skip slots which do not have embedding. each slot's embedding in a sparse table should be used in all training programs before fix this.
* fix pull sparse, skip slots which do not have embedding.
* fix collect feasign label info, skip slots which do not have embedding.
* support when there are multi sparse tables in one or multi training programs, each program can pull/push its own related sparse tables instead of all sparse tables.
* test=develop

* add copy table (#21086)

* copy some feasigns and corresponding embeddings from one sparse table to another
* copy all feasigns and corresponding embeddings from one sparse table to another
* copy all dense params from one table to another
* copy some local vars to other local vars

* fix fs_client_param bug (#21212)

* fix fs_client_param bug， user can set this config through fleet_desc_file or fleet config
* test=develop

* fix fleet util bug (#21254)

* fix fleet util bug in save paddle inference model
* test=develop

* add pre condition check for fuse optimizer op pass, test=develop

* add log & set init to zero, test=develop

* fix test_fuse_all_reduce_pass failed, test=develop

* polish details, test=develop

* refine PADDLE_ENFORCE & remove needless VLOG, test=develop

* refactor op check method, test=develop

* delete paddle infershape enforce marco (#20832)

* Polish and arrange code in enforce.h (#20901)

* Enrich the type of error and declare the error type interfaces (#21024)

* Enrich the type of error and declare the error type interfaces, test=develop

* adjust tests to adapt new form, test=develop

* add inference deps with error_codes.pb.h, test=develop

* restore stack iter start pos, test=develop

* polish code based review comments, test=develop

* Add dependency for error_codes.proto (#21084)

* fix activation_functions deps, test=develop, test=document_fix

* add error_codes_proto deps, test=develop, test=document_fix

* try delete enforce.h, test=develop, test=document_fix

* change cuda enforce & add example (#21142)
test=release/1.6

[cherry-pick] fix squared_mat_sub_fuse_pass bug when elementwise_op input is persistable param test=develop test=release/1.6 (#21044)

fix squared_mat_sub_fuse_pass bug when elementwise_op input is persistable param

* fix infer crashes caused by conv/pool upgrades, test=release/1.6

* fix bug, test=release/1.6

cherry-pick1.6 simplify master+patch，remove ins when size != merge_size or has conflict slot  (#20941)

* simplify master+patch，remove ins when size != merge_size or has conflict slot
* test=develop

* add check nan / inf in downpour worker during training
* test=develop

* update pserver decay blocks

* update distributed notify handler

* add support to gcc8, add docker env
* remove the warning issue

* Serialize to pickle format (#20820)

test=develop

* save load problem fix and new feature add (#20823)

* fix persistable;

* fix save load bugs; test=develop

* fix bug; test=develop

* add example for new io api; test=develop

* addd example; test=develop

* Add IndicateVarDataType interface to block tensor is not initialized problem in OP GetExceptedKernelType (#20044)

* add indicate_var_data_type inferface, test=develop

* add unittests & polish error message, test=develop

* remove needless include, test=develop

* extract public function & polish message, test=develop

* delete empty var check, test=develop

* change data_type to pointer parameter, test=develop

* polish details, test=develop

* Replace risky GetInputType method with secure IndicateVarDataType interface (#20668)

* replace part of the old implementation, test=develop

* restore concat op, test=develop

* update all ops implemention & delete GetDataTypeOfVar func, test=develop

test=release/1.6

* add more err msg, test=develop

* add more unittests, test=release/1.6

test=release/1.6

test=release/1.6

* - Flushing mkl-dnn cache

test=develop

- Disabled clearing cache for LoadModel

- Added clearing of mkl-dnn cache when Executor is created

test=develop

- Do not clear for GPU places

test=develop

- compilation fix

test=develop

* - Moved clearing of mkl-dnn cache in destructor of executor

test=develop

* - Compilation fix

test=develop

- Reverted conditional clearing of mkl-dnn cache in Executors's
  destructor

test=develop

- compilation fix

* fix op log bug, test=release/1.6

* add unittests, test=release/1.6

* Fix communicator slow bug & fix communicator stop bug (#20366)

* test=develop,Fix communicator slow bug

* test=develop, delete if() in stop_worker()

* test=develop

* fix UT, test=develop

* fix bug in fetch handler, test=develop

* fix bug in fetch handler, test=develop

* test=develop, fix fetch barrier bug

* test=develop, bug fix

* test=develop, bug fix

* test=develop, fix bug

* test=develop,test=release/1.6

* support dump multi file
test=develop

* dump fix num file
test=develop

Fix parse content in CreatePreLoadReaders. Before this fix, if you use dataset.set_parse_content and dataset.preload, parse content didn't work.

* Add Multihead matmul fuse pass (#20167)

* Add multihead fuse pass for ernie opt

* Refine softmax

test=develop

* Refine cuda kernel

* Refine cuda version

* Refine cmake

test=develop

* refine header file

* refine test case and pass
* refine comments

* Delete useless code.

test=develop
Signed-off-by: Nzhaoyuchen <zhaoyuchen01@baidu.com>

test=release/1.6