(find-alternate-loop-head) ( bb -- bb' )

Vocabulary

compiler.cfg.linearization.private

Inputs

bb

an object

Outputs

bb'

an object

Definition

USING: accessors combinators.short-circuit
compiler.cfg.utilities kernel math sequences ;

IN: compiler.cfg.linearization.private

: (find-alternate-loop-head) ( bb -- bb' )
    dup {
        [ predecessor visited? not ]
        [ predecessors>> length 1 = ]
        [ predecessor successors>> length 1 = ]
        [ [ number>> ] [ predecessor number>> ] bi > ]
    } 1&& [ predecessor (find-alternate-loop-head) ] when ;