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: @louie5
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From: @laiyongqiang
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From: @xu_anyue
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From: @liujunzhu
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From: @jiangzg001
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From: @zh_qh
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From: @yuchaojie
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From: @caojian05
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