preference-guided-colors ( graph order affinities available -- colors )

Vocabulary

compiler.cfg.register-allocation.chordal

Inputs

graph	an object
order	an object
affinities	an object
available	an object

Outputs

colors

an object

Definition

USING: assocs compiler.cfg.registers cpu.architecture kernel
math sequences sets ;

IN: compiler.cfg.register-allocation.chordal

:: preference-guided-colors
    ( graph order affinities available -- colors )
    H{ } clone :> colors graph keys
    [ H{ } clone ] H{ } map>assoc
    :> preferences affinities affinity-chunks :> chunks chunks
    values [ first ] map members [ H{ } clone ] H{ } map>assoc
    :> chunk-preferences order [| vertex |
        vertex chunks at first chunk-preferences at
        :> shared vertex graph at [ colors at ] map
        sift :> occupied vertex rep-of reg-class-of available at
        length :> capacity capacity <iota>
        [ occupied member? not ] filter :> free free empty?
        [ vertex occupied capacity uncolorable-spill-result ]
        when free vertex preferences at
        shared preferred-free-color
        :> chosen chosen vertex colors set-at
        chosen shared inc-at vertex affinities at [| partner
        weight |
            chosen partner preferences at
            [ 0 or weight 8 * + ] change-at
        ] assoc-each
    ] each colors ;