factor/basis/compiler/cfg/parallel-copy/parallel-copy.factor

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2.3 KiB
Factor

! Copyright (C) 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: assocs cpu.architecture compiler.cfg.registers
compiler.cfg.instructions compiler.cfg.ssa.destruction.leaders
deques dlists fry kernel locals namespaces sequences hashtables ;
FROM: sets => conjoin ;
IN: compiler.cfg.parallel-copy
! Revisiting Out-of-SSA Translation for Correctness, Code Quality, and Efficiency
! http://hal.archives-ouvertes.fr/docs/00/34/99/25/PDF/OutSSA-RR.pdf,
! Algorithm 1
<PRIVATE
SYMBOLS: locs preds to-do ready ;
: init-to-do ( bs -- )
to-do get push-all-back ;
: init-ready ( bs -- )
locs get '[ _ key? not ] filter ready get push-all-front ;
: init ( mapping -- )
<dlist> to-do set
<dlist> ready set
[ preds set ]
[ [ nip dup ] H{ } assoc-map-as locs set ]
[ keys [ init-to-do ] [ init-ready ] bi ] tri ;
:: process-ready ( b quot: ( dst src -- ) -- )
b preds get at :> a
a locs get at :> c
b c quot call
b a locs get set-at
a c = a preds get at and [ a ready get push-front ] when ; inline
:: process-to-do ( b temp: ( src -- dst ) quot: ( dst src -- ) -- )
! Note that we check if b = loc(b), not b = loc(pred(b)) as the
! paper suggests. Confirmed by one of the authors at
! http://www.reddit.com/comments/93253/some_lecture_notes_on_ssa_form/c0bco4f
b locs get at b = [
b temp call :> temp
temp b quot call
temp b locs get set-at
b ready get push-front
] when ; inline
PRIVATE>
:: parallel-mapping ( mapping temp: ( src -- dst ) quot: ( dst src -- ) -- )
! mapping is a list of { dst src } pairs
[
mapping init
to-do get [
ready get [
quot process-ready
] slurp-deque
temp quot process-to-do
] slurp-deque
] with-scope ; inline
: parallel-copy ( mapping -- )
! mapping is a list of { dst src } pairs
next-vreg '[ drop _ ] [ any-rep ##copy, ] parallel-mapping ;
<PRIVATE
SYMBOL: temp-vregs
: temp-vreg ( rep -- vreg )
temp-vregs get [ next-vreg-rep ] cache
[ leader-map get conjoin ] keep ;
PRIVATE>
: parallel-copy-rep ( mapping -- )
! mapping is a list of { dst src } pairs
H{ } clone temp-vregs set
[ rep-of temp-vreg ] [ dup rep-of ##copy, ] parallel-mapping ;