* unify utils naming style

* polish details

* split phi and fluid infermeta context

* resolve conflict

* fix type error

* optimize scheduling perf

* spec small vector size

* replace all grad var name

* fix test failed

* move init defalut signature

* polish details

* polish details

* fix no init bug

* init sig for tests

* add init sig for infer

* fix infrt error

* fix infrt failed

* fix kunlun error

* fix infrt failed

* move clip op to phi

* fix as review

* update hierarchical_sigmoid_kernel.cc

* update selected_rows

* update clip_kernel.cu

* fix as review