loop-preheader ( loop entering -- preheader )

Vocabulary

compiler.cfg.loop-optimization

Inputs

loop	an object
entering	an object

Outputs

preheader

an object

Definition

USING: accessors kernel sequences ;

IN: compiler.cfg.loop-optimization

:: loop-preheader ( loop entering -- preheader )
    entering length 1 = [
        entering first :> pred pred successors>> length 1 =
        pred kill-block?>> not and
        [ pred ] [ loop entering create-loop-preheader ] if
    ] [ loop entering create-loop-preheader ] if ;