* update env setting

* update pass logic

* dist op support bf16

* backward cast update

* update setting

* update backward

* revert amp pass

* update fp16 backward logic

* register c_embedding bf16

* revert engine

* add unitest

* add unitest

* update unitest

* update cmake

* update math

* update math.py

* update unitest

* update unitest

* revise unitest

* revise unitest

* update unitest

* update unitest

* update unitest