factor/basis/compiler/cfg/liveness/liveness.factor

154 lines
4.5 KiB
Factor

! Copyright (C) 2009, 2010 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors assocs combinators combinators.short-circuit
compiler.cfg.def-use compiler.cfg.instructions
compiler.cfg.predecessors compiler.cfg.registers
compiler.cfg.rpo compiler.cfg.ssa.destruction.leaders
compiler.cfg.utilities compiler.utilities cpu.architecture
deques dlists fry kernel locals namespaces sequences sets ;
IN: compiler.cfg.liveness
SYMBOL: live-ins
: live-in ( bb -- set )
live-ins get at ;
SYMBOL: live-outs
: live-out ( bb -- set )
live-outs get at ;
SYMBOL: edge-live-ins
: edge-live-in ( predecessor basic-block -- set )
edge-live-ins get at at ;
SYMBOL: base-pointers
GENERIC: visit-insn ( live-set insn -- )
! This would be much better if live-set was a real set
: kill-defs ( live-set insn -- )
defs-vregs [ ?leader ] map
'[ drop ?leader _ in? ] assoc-reject! drop ; inline
: gen-uses ( live-set insn -- )
uses-vregs [ swap conjoin ] with each ; inline
M: vreg-insn visit-insn ( live-set insn -- )
[ kill-defs ] [ gen-uses ] 2bi ;
DEFER: lookup-base-pointer
GENERIC: lookup-base-pointer* ( vreg insn -- vreg/f )
M: ##tagged>integer lookup-base-pointer* nip src>> ;
M: ##unbox-any-c-ptr lookup-base-pointer*
! If the input to unbox-any-c-ptr was an alien and not a
! byte array, then the derived pointer will be outside of
! the data heap. The GC has to handle this case and ignore
! it.
nip src>> ;
M: ##copy lookup-base-pointer* nip src>> lookup-base-pointer ;
M: ##add-imm lookup-base-pointer* nip src1>> lookup-base-pointer ;
M: ##sub-imm lookup-base-pointer* nip src1>> lookup-base-pointer ;
M: ##parallel-copy lookup-base-pointer* values>> value-at ;
M: ##add lookup-base-pointer*
! If both operands have a base pointer, then the user better
! not be doing memory reads and writes on the object, since
! we don't give it a base pointer in that case at all.
nip [ src1>> ] [ src2>> ] bi [ lookup-base-pointer ] bi@ xor ;
M: ##sub lookup-base-pointer*
nip src1>> lookup-base-pointer ;
M: vreg-insn lookup-base-pointer* 2drop f ;
: lookup-base-pointer ( vreg -- vreg/f )
base-pointers get ?at [
f over base-pointers get set-at
[ dup ?leader insn-of lookup-base-pointer* ] keep
dupd base-pointers get set-at
] unless ;
:: visit-derived-root ( vreg derived-roots gc-roots -- )
vreg lookup-base-pointer :> base
base [
{ vreg base } derived-roots push
base gc-roots adjoin
] when ;
: visit-gc-root ( vreg derived-roots gc-roots -- )
pick rep-of {
{ tagged-rep [ nip adjoin ] }
{ int-rep [ visit-derived-root ] }
[ 4drop ]
} case ;
: gc-roots ( live-set -- derived-roots gc-roots )
keys V{ } clone HS{ } clone
[ '[ _ _ visit-gc-root ] each ] 2keep members ;
: fill-gc-map ( live-set gc-map -- )
[ gc-roots ] dip [ gc-roots<< ] [ derived-roots<< ] bi ;
M: gc-map-insn visit-insn ( live-set insn -- )
[ kill-defs ] [ gc-map>> fill-gc-map ] [ gen-uses ] 2tri ;
M: ##phi visit-insn kill-defs ;
M: insn visit-insn 2drop ;
: transfer-liveness ( live-set insns -- )
<reversed> [ visit-insn ] with each ;
: compute-live-in ( basic-block -- live-in )
[ live-out clone dup ] keep instructions>> transfer-liveness ;
: compute-edge-live-in ( basic-block -- edge-live-in )
H{ } clone [
'[ inputs>> [ swap _ conjoin-at ] assoc-each ] each-phi
] keep ;
: update-live-in ( basic-block -- changed? )
[ [ compute-live-in ] keep live-ins get maybe-set-at ]
[ [ compute-edge-live-in ] keep edge-live-ins get maybe-set-at ]
bi or ;
: compute-live-out ( basic-block -- live-out )
[ successors>> [ live-in ] map ]
[ dup successors>> [ edge-live-in ] with map ] bi
append assoc-combine ;
: update-live-out ( basic-block -- changed? )
[ compute-live-out ] keep
live-outs get maybe-set-at ;
: update-live-out/in ( basic-block -- changed? )
{ [ update-live-out ] [ update-live-in ] } 1&& ;
: liveness-step ( basic-block -- basic-blocks )
[ update-live-out/in ] keep predecessors>> { } ? ;
: init-liveness ( -- )
H{ } clone live-ins namespaces:set
H{ } clone edge-live-ins namespaces:set
H{ } clone live-outs namespaces:set
H{ } clone base-pointers namespaces:set ;
: compute-live-sets ( cfg -- )
init-liveness
dup needs-predecessors dup compute-insns
post-order <hashed-dlist> [ push-all-front ] keep
[ liveness-step ] slurp/replenish-deque ;
: live-in? ( vreg bb -- ? ) live-in key? ;
: live-out? ( vreg bb -- ? ) live-out key? ;