Add the demo of subgraph splitter

* listen_and_serv use localscope

* fix ut

* Fix a bug related to dispensable inputs and refine the inference unittest.

* Fix the use of dispensable inputs in reshape_op.

* Polish the enforce statements.

* Fix an English writing typo.

This reverts commit 0446220e.

Reason:

Rerun failed test hides flaky test.
Flaky test can be bugs, for example, race condition.
Test shouldn't be flaky, if a test is flaky, it should be fixed.

* CI: rerun failed tests.

* fix check style error.

generate timeline file
PYTHONPATH=/paddle/dev/my/build2/python/ python /paddle/dev/my/Paddle2/tools/timeline.py --profile_path=train=run_inference_profiler --timeline_path=/tmp/timeline_infer
visualize it
open url chrome://tracing

* init refactor

* init

* update some comment

* fix build

* fix errorrr

* fix bug

* fix comment

* update

We need to figure out if tensorrt
use row-major or col-major for tensor
layerout inorder to do conversion.

* init

* init

* add ut

* split singleton from base class

* add singleton

* ad singleton

* add test float16 inference accuracy example

* complete the test

* clean code

* add argument parse and refine tests

* add shell script

* add float16 benchmark code

* refine code

* prepare for contrib/float16

* put things in contrib float16 folder

* update benchmark result

* further update benchmark report

* add float16 inference report

* update report

* Fix CPPLint issues in fluid/inference/tensorrt/

* Fix compile errors

* add float16 transpiler

* fix feed fetch target names mismatch

* fix cast op input change issue

* fix program desc flush error

* fix inconsistent var names in block desc bug

* code clean up

* add float16 infernce C++ example and fix prune bug

* Fix CPPLint issue in test_engine

* Fix CPPLint errors in operators/math

* Fix compilation

* Fix more CPPLint issues

* Fix more CPPLint issues

* Fix more CPPLint issues

* Fix CPPLint issues in operators/math and operators/reader