check-value-flow ( cfg snapshot -- )

Vocabulary

compiler.cfg.register-allocation.verifier

Inputs

cfg	an object
snapshot	an object

Outputs

None

Definition

USING: assocs compiler.cfg.predecessors compiler.cfg.rpo kernel
sequences ;

IN: compiler.cfg.register-allocation.verifier

:: check-value-flow ( cfg snapshot -- )
    cfg needs-predecessors
    cfg snapshot check-value-flow-presence
    cfg reverse-post-order :> blocks
    H{ } clone :> states t :> changed!
    [ changed ] [
        f changed! blocks [| bb |
            bb cfg states snapshot incoming-value-flow-state [|
            incoming |
                bb incoming snapshot f transfer-value-flow-block
                :> outgoing outgoing bb states at =
                [ ] [ outgoing bb states set-at t changed! ] if
            ] when*
        ] each
    ] while blocks [| bb |
        bb cfg states snapshot incoming-value-flow-state [|
        incoming |
            bb incoming snapshot t transfer-value-flow-block
            drop
        ] when*
    ] each ;