1. add case to guard precision
2. fix a shape bug
3. fix a funcGraph bug

- It provides a unified style to express graph and kernel for user.
- It provides a unified IR to represent graph and kernel for developer.
- It breaks the boundary between graph and kernel.
- It provides more opportunities to do compile optimization.

Signed-off-by: zhoufeng <zhoufeng54@huawei.com>

Signed-off-by: leonwanghui <leon.wanghui@huawei.com>