factor/basis/compiler/cfg/linear-scan/live-intervals/live-intervals.factor

190 lines
5.2 KiB
Factor

! Copyright (C) 2008, 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: namespaces kernel assocs accessors sequences math math.order fry
combinators binary-search compiler.cfg.instructions compiler.cfg.registers
compiler.cfg.def-use compiler.cfg.liveness compiler.cfg.linearization.order
compiler.cfg ;
IN: compiler.cfg.linear-scan.live-intervals
TUPLE: live-range from to ;
C: <live-range> live-range
TUPLE: live-interval
vreg
reg spill-to reload-from
start end ranges uses ;
GENERIC: covers? ( insn# obj -- ? )
M: f covers? 2drop f ;
M: live-range covers? [ from>> ] [ to>> ] bi between? ;
M: live-interval covers? ( insn# live-interval -- ? )
ranges>>
dup length 4 <= [
[ covers? ] with any?
] [
[ drop ] [ [ from>> <=> ] with search nip ] 2bi
covers?
] if ;
: add-new-range ( from to live-interval -- )
[ <live-range> ] dip ranges>> push ;
: shorten-range ( n live-interval -- )
dup ranges>> empty?
[ dupd add-new-range ] [ ranges>> last (>>from) ] if ;
: extend-range ( from to live-range -- )
ranges>> last
[ max ] change-to
[ min ] change-from
drop ;
: extend-range? ( to live-interval -- ? )
ranges>> [ drop f ] [ last from>> >= ] if-empty ;
: add-range ( from to live-interval -- )
2dup extend-range?
[ extend-range ] [ add-new-range ] if ;
GENERIC: operands-in-registers? ( insn -- ? )
M: vreg-insn operands-in-registers? drop t ;
M: partial-sync-insn operands-in-registers? drop f ;
: add-def ( insn live-interval -- )
[ insn#>> ] [ uses>> ] bi* push ;
: add-use ( insn live-interval -- )
! Every use is a potential def, no SSA here baby!
over operands-in-registers? [ add-def ] [ 2drop ] if ;
: <live-interval> ( vreg -- live-interval )
\ live-interval new
V{ } clone >>uses
V{ } clone >>ranges
swap >>vreg ;
: block-from ( bb -- n ) instructions>> first insn#>> 1 - ;
: block-to ( bb -- n ) instructions>> last insn#>> ;
M: live-interval hashcode*
nip [ start>> ] [ end>> 1000 * ] bi + ;
! Mapping from vreg to live-interval
SYMBOL: live-intervals
: live-interval ( vreg -- live-interval )
live-intervals get [ <live-interval> ] cache ;
GENERIC: compute-live-intervals* ( insn -- )
M: insn compute-live-intervals* drop ;
: handle-output ( insn vreg -- )
live-interval
[ [ insn#>> ] dip shorten-range ] [ add-def ] 2bi ;
: handle-input ( insn vreg -- )
live-interval
[ [ [ basic-block get block-from ] dip insn#>> ] dip add-range ] [ add-use ] 2bi ;
: handle-temp ( insn vreg -- )
live-interval
[ [ insn#>> dup ] dip add-range ] [ add-use ] 2bi ;
M: vreg-insn compute-live-intervals*
[ dup defs-vreg [ handle-output ] with when* ]
[ dup uses-vregs [ handle-input ] with each ]
[ dup temp-vregs [ handle-temp ] with each ]
tri ;
: handle-live-out ( bb -- )
[ block-from ] [ block-to ] [ live-out keys ] tri
[ live-interval add-range ] with with each ;
! A location where all registers have to be spilled
TUPLE: sync-point n ;
C: <sync-point> sync-point
! Sequence of sync points
SYMBOL: sync-points
GENERIC: compute-sync-points* ( insn -- )
M: partial-sync-insn compute-sync-points*
insn#>> <sync-point> sync-points get push ;
M: insn compute-sync-points* drop ;
: compute-live-intervals-step ( bb -- )
[ basic-block set ]
[ handle-live-out ]
[
instructions>> <reversed> [
[ compute-live-intervals* ]
[ compute-sync-points* ]
bi
] each
] tri ;
: init-live-intervals ( -- )
H{ } clone live-intervals set
V{ } clone sync-points set ;
: compute-start/end ( live-interval -- )
dup ranges>> [ first from>> ] [ last to>> ] bi
[ >>start ] [ >>end ] bi* drop ;
ERROR: bad-live-interval live-interval ;
: check-start ( live-interval -- )
dup start>> -1 = [ bad-live-interval ] [ drop ] if ;
: finish-live-intervals ( live-intervals -- seq )
! Since live intervals are computed in a backward order, we have
! to reverse some sequences, and compute the start and end.
values dup [
{
[ ranges>> reverse-here ]
[ uses>> reverse-here ]
[ compute-start/end ]
[ check-start ]
} cleave
] each ;
: compute-live-intervals ( cfg -- live-intervals sync-points )
init-live-intervals
linearization-order <reversed> [ compute-live-intervals-step ] each
live-intervals get finish-live-intervals
sync-points get ;
: relevant-ranges ( interval1 interval2 -- ranges1 ranges2 )
[ [ ranges>> ] bi@ ] [ nip start>> ] 2bi '[ to>> _ >= ] filter ;
: intersect-live-range ( range1 range2 -- n/f )
2dup [ from>> ] bi@ > [ swap ] when
2dup [ to>> ] [ from>> ] bi* >= [ nip from>> ] [ 2drop f ] if ;
: intersect-live-ranges ( ranges1 ranges2 -- n )
{
{ [ over empty? ] [ 2drop f ] }
{ [ dup empty? ] [ 2drop f ] }
[
2dup [ first ] bi@ intersect-live-range dup [ 2nip ] [
drop
2dup [ first from>> ] bi@ <
[ [ rest-slice ] dip ] [ rest-slice ] if
intersect-live-ranges
] if
]
} cond ;
: intervals-intersect? ( interval1 interval2 -- ? )
relevant-ranges intersect-live-ranges >boolean ; inline