factor/basis/compiler/cfg/dependence/dependence.factor

157 lines
4.0 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.instructions compiler.cfg.registers fry kernel
locals namespaces sequences sets sorting math.vectors
make math combinators.short-circuit vectors ;
FROM: namespaces => set ;
IN: compiler.cfg.dependence
! Dependence graph construction
SYMBOL: roots
SYMBOL: node-number
SYMBOL: nodes
SYMBOL: +data+
SYMBOL: +control+
! Nodes in the dependency graph
! These need to be numbered so that the same instruction
! will get distinct nodes if it occurs multiple times
TUPLE: node
number insn precedes follows
children parent
registers parent-index ;
M: node equal? over node? [ [ number>> ] bi@ = ] [ 2drop f ] if ;
M: node hashcode* nip number>> ;
: <node> ( insn -- node )
node new
node-number counter >>number
swap >>insn
H{ } clone >>precedes
V{ } clone >>follows ;
: ready? ( node -- ? ) precedes>> assoc-empty? ;
:: precedes ( first second how -- )
how second first precedes>> set-at ;
:: add-data-edges ( nodes -- )
! This builds up def-use information on the fly, since
! we only care about local def-use
H{ } clone :> definers
nodes [| node |
node insn>> defs-vregs [ node swap definers set-at ] each
node insn>> uses-vregs [ definers at [ node +data+ precedes ] when* ] each
] each ;
UNION: stack-insn ##peek ##replace ##replace-imm ;
UNION: slot-insn
##read ##write ;
UNION: memory-insn
##load-memory ##load-memory-imm
##store-memory ##store-memory-imm
alien-call-insn
slot-insn ;
: chain ( node var -- )
dup get [
pick +control+ precedes
] when*
set ;
GENERIC: add-control-edge ( node insn -- )
M: stack-insn add-control-edge loc>> chain ;
M: memory-insn add-control-edge drop memory-insn chain ;
M: object add-control-edge 2drop ;
: add-control-edges ( nodes -- )
[ [ dup insn>> add-control-edge ] each ] with-scope ;
: set-follows ( nodes -- )
[
dup precedes>> keys [
follows>> push
] with each
] each ;
: set-roots ( nodes -- )
[ ready? ] V{ } filter-as roots set ;
: build-dependence-graph ( instructions -- )
[ <node> ] map {
[ add-control-edges ]
[ add-data-edges ]
[ set-follows ]
[ set-roots ]
[ nodes set ]
} cleave ;
! Sethi-Ulmann numbering
:: calculate-registers ( node -- registers )
node children>> [ 0 ] [
[ [ calculate-registers ] map natural-sort ]
[ length iota ]
bi v+ supremum
] if-empty
node insn>> temp-vregs length +
dup node registers<< ;
! Constructing fan-in trees
: attach-parent ( node parent -- )
[ >>parent drop ]
[ [ ?push ] change-children drop ] 2bi ;
: keys-for ( assoc value -- keys )
'[ nip _ = ] assoc-filter keys ;
: choose-parent ( node -- )
! If a node has control dependences, it has to be a root
! Otherwise, choose one of the data dependences for a parent
dup precedes>> +control+ keys-for empty? [
dup precedes>> +data+ keys-for [ drop ] [
first attach-parent
] if-empty
] [ drop ] if ;
: make-trees ( -- trees )
nodes get
[ [ choose-parent ] each ]
[ [ parent>> not ] filter ] bi ;
ERROR: node-missing-parent trees nodes ;
ERROR: node-missing-children trees nodes ;
: flatten-tree ( node -- nodes )
[ children>> [ flatten-tree ] map concat ] keep
suffix ;
: verify-parents ( trees -- trees )
nodes get over '[ [ parent>> ] [ _ member? ] bi or ] all?
[ nodes get node-missing-parent ] unless ;
: verify-children ( trees -- trees )
dup [ flatten-tree ] map concat
nodes get
{ [ [ length ] bi@ = ] [ set= ] } 2&&
[ nodes get node-missing-children ] unless ;
: verify-trees ( trees -- trees )
verify-parents verify-children ;
: build-fan-in-trees ( -- )
make-trees verify-trees [
-1/0. >>parent-index
calculate-registers drop
] each ;