factor/basis/compiler/cfg/linear-scan/allocation/coalescing/coalescing.factor

35 lines
1.1 KiB
Factor

! Copyright (C) 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors kernel sequences namespaces assocs fry
combinators.short-circuit
compiler.cfg.linear-scan.live-intervals
compiler.cfg.linear-scan.allocation.state ;
IN: compiler.cfg.linear-scan.allocation.coalescing
: active-interval ( vreg -- live-interval )
dup [ dup active-intervals-for [ vreg>> = ] with find nip ] when ;
: avoids-inactive-intervals? ( live-interval -- ? )
dup vreg>> inactive-intervals-for
[ intervals-intersect? not ] with all? ;
: coalesce? ( live-interval -- ? )
{
[ copy-from>> active-interval ]
[ [ start>> ] [ copy-from>> active-interval end>> ] bi = ]
[ avoids-inactive-intervals? ]
} 1&& ;
: reuse-spill-slot ( old new -- )
[ vreg>> spill-slots get at ] dip '[ _ vreg>> spill-slots get set-at ] when* ;
: reuse-register ( old new -- )
reg>> >>reg drop ;
: (coalesce) ( old new -- )
[ add-active ] [ [ delete-active ] [ add-handled ] bi ] bi* ;
: coalesce ( live-interval -- )
dup copy-from>> active-interval
[ reuse-spill-slot ] [ reuse-register ] [ (coalesce) ] 2tri ;