factor/basis/compiler/cfg/stacks/vacant/vacant.factor

97 lines
2.7 KiB
Factor

USING: accessors arrays assocs classes.tuple compiler.cfg.dataflow-analysis
compiler.cfg.instructions compiler.cfg.registers fry kernel math math.order
sequences sets ;
IN: compiler.cfg.stacks.vacant
! Utils
: write-slots ( tuple values slots -- )
[ execute( x y -- z ) ] 2each drop ;
! Operations on the stack info
: register-write ( n stack -- stack' )
first2 rot suffix members 2array ;
: adjust-stack ( n stack -- stack' )
first2 pick '[ _ + ] map [ + ] dip 2array ;
: read-ok? ( n stack -- ? )
[ first >= ] [ second in? ] 2bi or ;
: stack>vacant ( stack -- seq )
first2 [ 0 max iota ] dip diff ;
: vacant>bits ( vacant -- bits )
[ { } ] [
dup supremum 1 + 1 <array>
[ '[ _ 0 -rot set-nth ] each ] keep
] if-empty ;
: stack>overinitialized ( stack -- seq )
second [ 0 < ] filter ;
: overinitialized>bits ( overinitialized -- bits )
[ neg 1 - ] map vacant>bits ;
: stack>scrub-and-check ( stack -- pair )
[ stack>vacant vacant>bits ]
[ stack>overinitialized overinitialized>bits ] bi 2array ;
! Operations on the analysis state
: state>gc-data ( state -- gc-data )
[ stack>scrub-and-check ] map ;
CONSTANT: initial-state { { 0 { } } { 0 { } } }
: insn>location ( insn -- n ds? )
loc>> [ n>> ] [ ds-loc? ] bi ;
: visit-replace ( state insn -- state' )
[ first2 ] dip insn>location
[ rot register-write swap ] [ swap register-write ] if 2array ;
ERROR: vacant-peek insn ;
: peek-loc-ok? ( state insn -- ? )
insn>location 0 1 ? rot nth read-ok? ;
GENERIC: visit-insn ( state insn -- state' )
M: ##inc-d visit-insn ( state insn -- state' )
n>> swap first2 [ adjust-stack ] dip 2array ;
M: ##inc-r visit-insn ( state insn -- state' )
n>> swap first2 swapd adjust-stack 2array ;
M: ##replace-imm visit-insn visit-replace ;
M: ##replace visit-insn visit-replace ;
M: ##peek visit-insn ( state insn -- state' )
2dup peek-loc-ok? [ drop ] [ vacant-peek ] if ;
M: ##call visit-insn ( state insn -- state' )
! After a word call, we can't trust any overinitialized locations
! to contain valid pointers anymore.
drop [ first2 [ 0 >= ] filter 2array ] map ;
: set-gc-map ( state gc-map -- )
swap state>gc-data concat
{ >>scrub-d >>check-d >>scrub-r >>check-r } write-slots ;
M: gc-map-insn visit-insn ( state insn -- state' )
dupd gc-map>> set-gc-map ;
M: insn visit-insn ( state insn -- state' )
drop ;
FORWARD-ANALYSIS: vacant
M: vacant-analysis transfer-set ( in-set bb dfa -- out-set )
drop instructions>> swap [ visit-insn ] reduce ;
M: vacant-analysis ignore-block? ( bb dfa -- ? )
2drop f ;
! Picking the first means that a block will only be analyzed once.
M: vacant-analysis join-sets ( sets bb dfa -- set )
2drop [ initial-state ] [ first ] if-empty ;