-! Copyright (C) 2009 Slava Pestov.
+! Copyright (C) 2009, 2011 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
-USING: accessors assocs fry kernel locals math math.order
-sequences namespaces sets
-compiler.cfg.rpo
-compiler.cfg.def-use
-compiler.cfg.utilities
-compiler.cfg.dominance
-compiler.cfg.instructions
-compiler.cfg.liveness.ssa
-compiler.cfg.critical-edges
-compiler.cfg.ssa.destruction.state
-compiler.cfg.ssa.destruction.forest
-compiler.cfg.ssa.destruction.copies
-compiler.cfg.ssa.destruction.renaming
-compiler.cfg.ssa.destruction.live-ranges
-compiler.cfg.ssa.destruction.process-blocks ;
+USING: accessors arrays assocs combinators compiler.cfg.def-use
+compiler.cfg.dominance compiler.cfg.instructions
+compiler.cfg.liveness compiler.cfg.parallel-copy
+compiler.cfg.registers compiler.cfg.rpo compiler.cfg.ssa.cssa
+compiler.cfg.ssa.destruction.leaders
+compiler.cfg.ssa.interference
+compiler.cfg.ssa.interference.live-ranges compiler.cfg.utilities
+cpu.architecture kernel locals make namespaces sequences sets ;
+FROM: namespaces => set ;
IN: compiler.cfg.ssa.destruction
-! Based on "Fast Copy Coalescing and Live-Range Identification"
-! http://www.cs.ucsd.edu/classes/sp02/cse231/kenpldi.pdf
-
-! Dominance, liveness and def-use need to be computed
-
-: process-blocks ( cfg -- )
- [ [ process-block ] if-has-phis ] each-basic-block ;
-
-SYMBOL: seen
-
-:: visit-renaming ( dst assoc src bb -- )
- src seen get key? [
- src dst bb add-waiting
- src assoc delete-at
- ] [ src seen get conjoin ] if ;
-
-:: break-interferences ( -- )
- H{ } clone seen set
- renaming-sets get [| dst assoc |
- assoc [| src bb |
- dst assoc src bb visit-renaming
- ] assoc-each
- ] assoc-each ;
-
-: remove-phis-from-block ( bb -- )
- instructions>> [ ##phi? not ] filter-here ;
-
-: remove-phis ( cfg -- )
- [ [ remove-phis-from-block ] if-has-phis ] each-basic-block ;
-
-: destruct-ssa ( cfg -- cfg' )
- dup cfg-has-phis? [
- dup split-critical-edges
- compute-ssa-live-sets
- init-coalescing
- dup compute-def-use
- dup compute-dominance
- dup compute-live-ranges
- dup process-blocks
- break-interferences
- dup perform-renaming
- insert-copies
- dup remove-phis
- ] when ;
\ No newline at end of file
+SYMBOL: class-element-map
+
+: class-elements ( vreg -- elts ) class-element-map get at ;
+
+<PRIVATE
+
+! Sequence of vreg pairs
+SYMBOL: copies
+
+: value-of ( vreg -- value )
+ dup insn-of dup ##tagged>integer? [ nip src>> ] [ drop ] if ;
+
+: init-coalescing ( -- )
+ defs get
+ [ keys unique leader-map set ]
+ [
+ [ [ dup dup value-of ] dip <vreg-info> 1array ] assoc-map
+ class-element-map set
+ ] bi
+ V{ } clone copies set ;
+
+: coalesce-elements ( merged vreg1 vreg2 -- )
+ ! delete leader1's class, and set leader2's class to merged.
+ class-element-map get [ delete-at ] [ set-at ] bi-curry bi* ;
+
+: coalesce-vregs ( merged leader1 leader2 -- )
+ 2dup swap leader-map get set-at coalesce-elements ;
+
+GENERIC: prepare-insn ( insn -- )
+
+: maybe-eliminate-copy-later ( dst src -- )
+ 2array copies get push ;
+
+M: insn prepare-insn drop ;
+
+M: alien-call-insn prepare-insn drop ;
+
+M: vreg-insn prepare-insn
+ [ temp-vregs [ leader-map get conjoin ] each ]
+ [
+ [ defs-vregs ] [ uses-vregs ] bi
+ 2dup [ empty? not ] both? [
+ [ first ] bi@
+ 2dup [ rep-of reg-class-of ] bi@ eq?
+ [ maybe-eliminate-copy-later ] [ 2drop ] if
+ ] [ 2drop ] if
+ ] bi ;
+
+M: ##copy prepare-insn
+ [ dst>> ] [ src>> ] bi maybe-eliminate-copy-later ;
+
+M: ##parallel-copy prepare-insn
+ values>> [ first2 maybe-eliminate-copy-later ] each ;
+
+: leaders ( vreg1 vreg2 -- vreg1' vreg2' )
+ [ leader ] bi@ ;
+
+: vregs-interfere? ( vreg1 vreg2 -- merged/f ? )
+ [ class-elements ] bi@ sets-interfere? ;
+
+ERROR: vregs-shouldn't-interfere vreg1 vreg2 ;
+
+:: must-eliminate-copy ( vreg1 vreg2 -- )
+ ! Eliminate a copy.
+ vreg1 vreg2 = [
+ vreg1 vreg2 vregs-interfere?
+ [ vreg1 vreg2 vregs-shouldn't-interfere ]
+ [ vreg1 vreg2 coalesce-vregs ]
+ if
+ ] unless ;
+
+M: ##tagged>integer prepare-insn
+ [ dst>> ] [ src>> ] bi leaders must-eliminate-copy ;
+
+M: ##phi prepare-insn
+ [ dst>> ] [ inputs>> values ] bi
+ [ leaders must-eliminate-copy ] with each ;
+
+: prepare-coalescing ( cfg -- )
+ init-coalescing
+ [ [ prepare-insn ] each ] simple-analysis ;
+
+:: maybe-eliminate-copy ( vreg1 vreg2 -- )
+ ! Eliminate a copy if possible.
+ vreg1 vreg2 = [
+ vreg1 vreg2 vregs-interfere?
+ [ drop ] [ vreg1 vreg2 coalesce-vregs ] if
+ ] unless ;
+
+: process-copies ( copies -- )
+ [ leaders maybe-eliminate-copy ] assoc-each ;
+
+: perform-coalescing ( cfg -- )
+ prepare-coalescing copies get process-copies ;
+
+GENERIC: cleanup-insn ( insn -- )
+
+: useful-copy? ( insn -- ? )
+ [ dst>> ] [ src>> ] bi leaders = not ; inline
+
+M: ##copy cleanup-insn
+ dup useful-copy? [ , ] [ drop ] if ;
+
+M: ##parallel-copy cleanup-insn
+ values>> [ leaders ] assoc-map [ first2 = ] reject
+ parallel-copy-rep % ;
+
+M: ##tagged>integer cleanup-insn
+ dup useful-copy? [ , ] [ drop ] if ;
+
+M: ##phi cleanup-insn drop ;
+
+M: insn cleanup-insn , ;
+
+: cleanup-cfg ( cfg -- )
+ [ [ [ cleanup-insn ] each ] V{ } make ] simple-optimization ;
+
+PRIVATE>
+
+: destruct-ssa ( cfg -- )
+ f leader-map set
+ {
+ needs-dominance
+ construct-cssa
+ compute-defs
+ compute-insns
+ compute-live-sets
+ compute-live-ranges
+ perform-coalescing
+ cleanup-cfg
+ compute-live-sets
+ } apply-passes ;
projects / factor.git / blobdiff