The basic idea is: exploits data dependency to control the execution order
of side-effect operations, and keep the semantics of ANF unchanged.

The ControlDepend primitive is removed and there are two primitives added:

1. UpdateState:
```
  a = Assign(para, value)
```
became:
```
  a = Assign(para, value, u)
  u = UpdateState(u, a)
```

2. Load:
```
  x = Add(para, value)
```
became:
```
  p = Load(para, u)
  x = Add(p, value)
  u = UpdateState(u, p)
```

add support for pynative pass

add testcases

This reverts commit 7a7e499475.

This reverts commit f3a9fbdd78.

Merge pull request !2969 from BowenK/fix_reduce_all

Merge pull request !2948 from amongo/FixControlFlow

add join for ref

adjust env eliminate to eliminate all env ops

add partial app cache

resolve while endless

fix env eliminate

support for "for while" cases

fix join shape error

Merge pull request !3270 from thlinh/dev_Jul17_removeSelect

Create a new pass named ValueBasedEliminate to reduce the load of Arithmetic Simplify

Code review

update logic for cache

clean up code

add test cases for new api

update include of code

specify the resolve attr to ClassMember

avoid resolve attr of self