some comments in backward_slice.py
some comments in backward_slice.py

haylesr/angr,f-prettyland/angr,chubbymaggie/angr,angr/angr,tyb0807/angr,axt/angr,f-prettyland/angr,chubbymaggie/angr,schieb/angr,f-prettyland/angr,chubbymaggie/angr,iamahuman/angr,schieb/angr,angr/angr,axt/angr,schieb/angr,angr/angr,tyb0807/angr,iamahuman/angr,iamahuman/angr,axt/angr,tyb0807/angr,haylesr/angr