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

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

1. Search call info before insert nodes for control flow calls;
2. Use label_switch for multi return points if required.

2. Dump the end graph in gpu session and cu session

From: @louie5
Reviewed-by: @ouwenchang,@lixiaohui33
Signed-off-by: @lixiaohui33

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

From: @HulkTang
Reviewed-by: @zhoufeng54,@jjfeing
Signed-off-by: @jjfeing

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

From: @zpac
Reviewed-by: @cristoval,@wilfchen
Signed-off-by: @cristoval

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

Fixed cpplint

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

From: @anancds
Reviewed-by: @limingqi107,@cristoval
Signed-off-by: @cristoval

From: @HulkTang
Reviewed-by: @zhoufeng54,@chujinjin
Signed-off-by: @chujinjin

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

From: @HulkTang
Reviewed-by: @chujinjin
Signed-off-by:

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

From: @chuckchen521
Reviewed-by: 
Signed-off-by:

1. Remove output parameter pool for ascend control flow;
2. Remove duplicate code for Switch and SwitchLayer;
3. Add 'return' attribute to label_goto that used for return;
4. Disable tail call optimize for graphs with 'recursive' flag.

From: @liu_xiao_93
Reviewed-by: 
Signed-off-by:

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

From: @islam_amin
Reviewed-by: @john_tzanakakis,@tom__chen
Signed-off-by:

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

From: @yuchaojie
Reviewed-by: @kisnwang
Signed-off-by:

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

From: @chenyijie6
Reviewed-by: @kisnwang,@chujinjin
Signed-off-by: @chujinjin

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

From: @islam_amin
Reviewed-by: @john_tzanakakis,@yelihua
Signed-off-by: @yelihua