Optimize the concat and split kernel for specical cases when the number of inputs/outputs is 2 (#17415)

* Optimize the concat and split kernel for special cases that the number of inputs/outputs is 2.
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* Refine codes.
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* Correct the condition.
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* Move the define of tmp_data outside the if statement.

* Print the cudnn minor version.
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* Fix the case when in_num/o_num is 1 in concat/split op.
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* Remove const_cast.
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* update python APIs

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* update API.spec

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* update merge_selected_rows

* update API.spec

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* update API.spec

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* fix the comment of less_than

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* update API.spec

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* update API.spec

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* update API.spec

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* update API.spec

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* update API

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* add INT8 conv+relu6 fuse and enbale mobilentv2 INT8 test
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* change fasle and 0.0 to fuse_brelu and brelu_threshold
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change the "fuse_relu||fuse_brelu" to "unsigned_output"
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* Use relu instead of brelu as INT8 post-op because INT8 brelu is not enabled in mkldnn v0.18
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* continuous-integration fix
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* - changes to graph detector

- Changes to pass

- Added ut for new pass

- use_pass

- Added pass to mkldnn passes

- fix to registration

- improved verbose messaging for conv bias passes

- Lint fixes

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* - Lint fixes

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* [DOC] Fix api docs, test=develop, test=document_preview

* [DOC] Fix api annotation: fluid.layers.tensor_array_to_tensor. test=develop, test=document_preview

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update MD5 of tensor_array_to_tensor

* fix the api example for create_global_var, create_parameter, SGDOptimizer, RMSPropOptimizer, MomentumOptimizer, LarsMomentumOptimizer, FtrlOptimizer
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* add example for adamoptimizer
fix API.spec
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* Bias correction for exponential moving average

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* Fix docs

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This reverts commit f34830e2.

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* Enable sqrt operator for the nGraph Bridge.

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* Update activation_op.h

* add Concat quantization
add unit test for quantizing concat
fix for wrong value when the input is not in map of calculated scales
add use_quantizer to concat_op.cc
add scale_algo rules for concat

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* missing fix for multiple inputs quantize-squash

* wojtuss review fix: adding comment

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* fix the bug that sub_scope_ may be null in AnalysisPredictor::Run.

* add more directions about io APIs' docs.

* update the API.spec. test=develop test=document_preview

* enhance print

* Revert "Revert "Fix allocator bug""

This reverts commit 174d0d0b.

* Revert "fix travis ci"

This reverts commit 5656fa9f.

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* add inlined_vector.h, test=develop

* add inlined_vector_test,test=develop

* clean code of allocator,test=develop

* delete zero_size_allocator.h,test=develop

* fix failed unittest,test=develop

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* Add Dockerfile for cuda9 and cuda10

* add data parallel batch

* gather_op support int64_t index by adding a template typename

* add UT and rename typename

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* Add Dockerfile for cuda9 and cuda10

Add Dockerfile for building cuda9 cuda10 images.

* fluid int8 train and trt int8 predict align.
trt int8 predict init
op converter

* 2. align fluid int8 train and trt int8 inference.
enhance quant dequant fuse pass
enhance op converter, trt engine, trt engine op, trt subgraph pass.

* 3. add delete_quant_dequant_pass for trt

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* 4. add the missing file
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* 5. i modify the c++ interface, but forget to modify the pybind code
fix the IS_TRT_VERSION_GE bug, and fix elementwise op converter
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* fuse mul and elementwise add to fc

* Reimplement the FC forward operator

* Fix FC MKLDNN integration by transposing weights

* Add FC MKLDNN Pass

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* FC MKLDNN Pass: change memcpy to std::copy

* Fix MKLDNN FC handling of mismatch input and weights dims

* Lower tolerance for MKL-DNN in resnet50 test

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* Adjust FC to support MKLDNN Op placement

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* Adjust Placement Op to set use_mkldnn attribute for graph

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* MKLDNN FC: fix weights format so that gemm version is called

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* FC MKLDNN: Remove tolerance decrease from tester_helper

* FC MKL-DNN: Refactor the code, change input reorder to weight reorder

* MKL-DNN FC: Introduce operator caching

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* FC MKL-DNN: Fix the tensor type in ExpectedKernelType

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* FC MKL-DNN: fix style changes

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* FC MKL-DNN: fallback to native on non-supported dim sizes

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* FC MKLDNN: fix CMake paths

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* FC MKLDNN: Refine placement pass graph mkldnn attribute

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* Fix Transpiler error for fuse_conv_eltwise

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* Fix missing STL includes in files

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* FC MKL-DNN: Enable new output size computation

Also, refine pass to comply with newest interface.
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* FC MKL-DNN: enable only when fc_mkldnn_pass is enabled

* FC MKL-DNN: Allow Weights to use oi or io format

* FC MKL-DNN: Adjust UT to work with correct dims

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* Enable MKL DEBUG for resnet50 analyzer

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* FC MKL-DNN: Improve Hashing function

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* FC MKL-DNN: Fix shape for fc weights in transpiler

* FC MKL-DNN: Update input pointer in re-used fc primitive

* Add log for not handling fc fuse for unsupported dims

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* FC MKL-DNN: Move transpose from pass to Op Kernel

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* FC MKL-DNN: Disable transpose in unit test

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* FC MKL-DNN: Remove fc_mkldnn_pass from default list

* Correct Flag for fake data analyzer tests

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* FC MKL-DNN: Add comment about fc mkldnn pass disablement

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* FC MKL-DNN: Disable fc in int8 tests

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* add __str__ method for tensor and lodtensor to support print test=develop

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* fix example; test=develop

* fix api spec; test=develop

* fix api spec; test=develop

* add doc check
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* test=develop,test=document_preview

add blank line to fix format, add one more "import"

* fix bug; test=develop

* fix bug; test=develop

add Run Prepared Ctx, fix pybind problem

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* Fix the example code in some Python API.
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* Fix the example code in some Python API by adding import.
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* This PR adds broadcast for multi-process. And it could be used in dynamic graph to broadcast parameters.

Python examples of fluid.layers.io.double_buffer and some BuildStrategy's methods.

* add conv_concat_relu fuse

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* add test code

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* added missing include with unordered_map

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* review fixes for wojtuss

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* remove 'should (not) be fused' comment statements

one of them was invalid anyway

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* fix quantize_squash_pass segfault when there is no tensor linked do Bias input

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* add googlenet test

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* fix concat CreateKey not using input format

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* add profiler in tracer.cc

* add profiler in layer.cc
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* add profiler in Layer.cc
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