factor/basis/compiler/cfg/scheduling/scheduling.factor

136 lines
3.8 KiB
Factor

! Copyright (C) 2009, 2010 Daniel Ehrenberg.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors assocs combinators compiler.cfg.def-use
compiler.cfg.dependence compiler.cfg.instructions
compiler.cfg.registers compiler.cfg.rpo continuations
cpu.architecture fry hashtables kernel locals math math.order
namespaces random sequences sets vectors literals make
arrays
compiler.cfg.liveness
compiler.cfg.liveness.ssa ;
IN: compiler.cfg.scheduling
! Instruction scheduling to reduce register pressure, from:
! "Register-sensitive selection, duplication, and
! sequencing of instructions"
! by Vivek Sarkar, et al.
! http://portal.acm.org/citation.cfm?id=377849
ERROR: bad-delete-at key assoc ;
: check-delete-at ( key assoc -- )
2dup key? [ delete-at ] [ bad-delete-at ] if ;
: set-parent-indices ( node -- )
children>> building get length
'[ _ >>parent-index drop ] each ;
: remove-node ( node -- )
[ follows>> keys ] keep
'[ [ precedes>> _ swap check-delete-at ] each ]
[ [ ready? ] filter roots get push-all ] bi ;
: score ( insn -- n )
[ parent-index>> ] [ registers>> neg ] bi 2array ;
: pull-out-nth ( n seq -- elt )
[ nth ] [ remove-nth! drop ] 2bi ;
: select ( vector quot -- elt )
! This could be sped up by a constant factor
[ dup <enum> ] dip '[ _ call( insn -- score ) ] assoc-map
dup values supremum '[ nip _ = ] assoc-find
2drop swap pull-out-nth ; inline
: select-instruction ( -- insn/f )
roots get [ f ] [
[ score ] select
[ insn>> ]
[ set-parent-indices ]
[ remove-node ] tri
] if-empty ;
: (reorder) ( -- )
select-instruction [
, (reorder)
] when* ;
: cut-by ( seq quot -- before after )
dupd find drop [ cut ] [ f ] if* ; inline
: split-3-ways ( insns -- first middle last )
[ ##phi? not ] cut-by unclip-last ;
: reorder ( insns -- insns' )
split-3-ways [
build-dependence-graph
build-fan-in-trees
[ (reorder) ] V{ } make reverse
] dip suffix append ;
ERROR: not-all-instructions-were-scheduled old-bb new-bb ;
SYMBOL: check-scheduling?
t check-scheduling? set-global
:: check-instructions ( new-bb old-bb -- )
new-bb old-bb [ instructions>> ] bi@
[ [ length ] bi@ = ] [ [ unique ] bi@ = ] 2bi and
[ old-bb new-bb not-all-instructions-were-scheduled ] unless ;
ERROR: definition-after-usage vreg old-bb new-bb ;
:: check-usages ( new-bb old-bb -- )
H{ } clone :> useds
new-bb instructions>> split-3-ways drop nip
[| insn |
insn uses-vregs [ useds conjoin ] each
insn defs-vreg :> def-reg
def-reg useds key?
[ def-reg old-bb new-bb definition-after-usage ] when
] each ;
: check-scheduling ( new-bb old-bb -- )
[ check-instructions ] [ check-usages ] 2bi ;
: with-scheduling-check ( bb quot: ( bb -- ) -- )
check-scheduling? get [
over dup clone
[ call( bb -- ) ] 2dip
check-scheduling
] [
call( bb -- )
] if ; inline
: number-insns ( insns -- )
[ >>insn# drop ] each-index ;
: clear-numbers ( insns -- )
[ f >>insn# drop ] each ;
: schedule-block ( bb -- )
[
[
[ number-insns ]
[ reorder ]
[ clear-numbers ] tri
] change-instructions drop
] with-scheduling-check ;
! Really, instruction scheduling should be aware that there are
! multiple types of registers, but this number is just used
! to decide whether to schedule instructions
: num-registers ( -- x ) int-regs machine-registers at length ;
: might-spill? ( bb -- ? )
[ live-in assoc-size ]
[ instructions>> [ defs-vreg ] count ] bi
+ num-registers >= ;
: schedule-instructions ( cfg -- cfg' )
dup [
dup might-spill?
[ schedule-block ]
[ drop ] if
] each-basic-block ;