8231988: Unexpected test result caused by C2 IdealLoopTree::do_remove_empty_loop Summary: Duplicate cmp node in empty loop if it has other users Reviewed-by: neliasso, thartmann Contributed-by: wanghuang3@huawei.com, xietuo@huawei.com

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test/nashorn/script/external
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NashornProfile.txt
**/JTreport/**
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