Merge pull request !2461 from YuJianfeng/r0.5

Merge pull request !2369 from baihuawei/reduce

Merge pull request !2393 from lianliguang/fix-bug-of-merge-cast-to-op-and-gene-hccl-kernel-info

- 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.

Merge pull request !2384 from YuJianfeng/split

Merge pull request !2394 from kisnwang/add-cpu-outputsync

Merge pull request !2056 from zhoufeng/enable-new-control-sink

Merge pull request !2157 from hangq/master

Merge pull request !2338 from chenweifeng/nezha

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

Merge pull request !2355 from dengwentao/fix_sub_op

Merge pull request !2358 from YuJianfeng/proximal

Merge pull request !2361 from kisnwang/fix-codex-reviewbot

Merge pull request !2346 from wangcong/master

Merge pull request !2264 from liuxiao/Adapt-ApplyProximalAdagrad-operator-for-vm

Merge pull request !2315 from yanzhenxiang2020/add_pack_open

Merge pull request !2307 from baihuawei/cpulstm

Merge pull request !2285 from jjfeing/master

Merge pull request !2290 from yanzhenxiang2020/aicpu_param_open

Merge pull request !2281 from zyli2020/add_sigmoid

Merge pull request !2280 from chenjianping/host_reduce

Merge pull request !2246 from kisnwang/fix-cpu-argmax

Merge pull request !2265 from dengwentao/code_check

Merge pull request !2251 from YuJianfeng/proximal

Merge pull request !2222 from wangcong/master

Merge pull request !2150 from chenweifeng/tanh-fp16