From: @dayschan
Reviewed-by: @ckey_dou,@gaoxiong1
Signed-off-by: @gaoxiong1

From: @jiaoy1224
Reviewed-by: @gaoxiong1,@gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @wenfangpei
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @wenfangpei
Reviewed-by: @gaoxiong1,@ckey_dou,@gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou,@ckey_dou

From: @tronzhang
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

Use a disjoint-set to maintain the clusters before building anf-graph, to speed up the process of building graph.
Dump the change of nodes to file if the graphkernel flag "dump_as_text" is set.

The algorithm of CheckCircle is unchanged.
Reuse the FuseNodesToSubGraph interface.

From: @wenfangpei
Reviewed-by: @ckey_dou,@gaoxiong1
Signed-off-by: @ckey_dou

From: @lingyunli63
Reviewed-by: @ckey_dou,@gaoxiong1
Signed-off-by: @gaoxiong1

From: @r1chardf1d0
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @wenfangpei
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @zengzitao
Reviewed-by: @ckey_dou,@gaoxiong1
Signed-off-by: @gaoxiong1

fix compiling

From: @hwhewei
Reviewed-by: @zh_qh,@ginfung
Signed-off-by: @zh_qh

From: @lingyunli63
Reviewed-by: @gaoxiong1,@anyrenwei
Signed-off-by: @anyrenwei

support castup, type-insensitive to type-insensitive, castup

refactor reorder_ops

fix compiling

move reorder_ops pass to later

fix abstract

refactor

fix node input num bug

1. set class GraphKernel as deprecated, and treat it as Cell
2. set class InplaceAssign as deprecated, suggested using Assign instead.
3. set op_selector as deprecated, removed the _selected_ops and _selected_grad_ops, replaced with real operations
4. removed the two passes of GraphKernel from frontend
5. removed the GraphKernel's codes from other modules

From: @hanhuifeng2020
Reviewed-by: @gaoxiong1,@dylangeng
Signed-off-by: @dylangeng

From: @lingyunli63
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @lingyunli63
Reviewed-by: @gaoxiong1,@dylangeng
Signed-off-by: @dylangeng

From: @lingyunli63
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @tronzhang
Reviewed-by: @ckey_dou,@gaoxiong1
Signed-off-by: @gaoxiong1

From: @r1chardf1d0
Reviewed-by: @gaoxiong1,@ckey_dou
Signed-off-by: @ckey_dou

From: @wenfangpei
Reviewed-by: @gaoxiong1,@anyrenwei
Signed-off-by: @anyrenwei

From: @huangbingjian
Reviewed-by: 
Signed-off-by: