factor/basis/compiler/cfg/ssa/construction/construction.factor

140 lines
3.4 KiB
Factor

! Copyright (C) 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: namespaces kernel accessors sequences fry assocs
sets math combinators
compiler.cfg
compiler.cfg.rpo
compiler.cfg.def-use
compiler.cfg.liveness
compiler.cfg.registers
compiler.cfg.dominance
compiler.cfg.instructions
compiler.cfg.renaming
compiler.cfg.renaming.functor
compiler.cfg.ssa.construction.tdmsc ;
FROM: namespaces => set ;
IN: compiler.cfg.ssa.construction
! The phi placement algorithm is implemented in
! compiler.cfg.ssa.construction.tdmsc.
! The renaming algorithm is based on "Practical Improvements to
! the Construction and Destruction of Static Single Assignment Form",
! however we construct pruned SSA, not semi-pruned SSA.
! http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.49.9683
<PRIVATE
! Maps vregs to sets of basic blocks
SYMBOL: defs
! Set of vregs defined in more than one basic block
SYMBOL: defs-multi
: compute-insn-defs ( bb insn -- )
defs-vreg dup [
defs get [ conjoin-at ] [ drop ] [ at assoc-size 1 > ] 2tri
[ defs-multi get conjoin ] [ drop ] if
] [ 2drop ] if ;
: compute-defs ( cfg -- )
H{ } clone defs set
H{ } clone defs-multi set
[
dup instructions>> [
compute-insn-defs
] with each
] each-basic-block ;
! Maps basic blocks to sequences of vregs
SYMBOL: inserting-phi-nodes
: insert-phi-node-later ( vreg bb -- )
2dup live-in key? [
[ predecessors>> over '[ _ ] H{ } map>assoc \ ##phi new-insn ] keep
inserting-phi-nodes get push-at
] [ 2drop ] if ;
: compute-phi-nodes-for ( vreg bbs -- )
keys merge-set [ insert-phi-node-later ] with each ;
: compute-phi-nodes ( -- )
H{ } clone inserting-phi-nodes set
defs-multi get defs get '[ _ at compute-phi-nodes-for ] assoc-each ;
: insert-phi-nodes-in ( phis bb -- )
[ append ] change-instructions drop ;
: insert-phi-nodes ( -- )
inserting-phi-nodes get [ swap insert-phi-nodes-in ] assoc-each ;
SYMBOLS: stacks pushed ;
: init-renaming ( -- )
H{ } clone stacks set ;
: gen-name ( vreg -- vreg' )
[ next-vreg dup ] dip
dup pushed get 2dup key?
[ 2drop stacks get at set-last ]
[ conjoin stacks get push-at ]
if ;
: top-name ( vreg -- vreg' )
stacks get at last ;
RENAMING: ssa-rename [ gen-name ] [ top-name ] [ ]
GENERIC: rename-insn ( insn -- )
M: insn rename-insn
[ ssa-rename-insn-uses ]
[ ssa-rename-insn-defs ]
bi ;
M: ##phi rename-insn
ssa-rename-insn-defs ;
: rename-insns ( bb -- )
instructions>> [ rename-insn ] each ;
: rename-successor-phi ( phi bb -- )
swap inputs>> [ top-name ] change-at ;
: rename-successor-phis ( succ bb -- )
[ inserting-phi-nodes get at ] dip
'[ _ rename-successor-phi ] each ;
: rename-successors-phis ( bb -- )
[ successors>> ] keep '[ _ rename-successor-phis ] each ;
: pop-stacks ( -- )
pushed get stacks get '[ drop _ at pop* ] assoc-each ;
: rename-in-block ( bb -- )
H{ } clone pushed set
[ rename-insns ]
[ rename-successors-phis ]
[
pushed get
[ dom-children [ rename-in-block ] each ] dip
pushed set
] tri
pop-stacks ;
: rename ( cfg -- )
init-renaming
entry>> rename-in-block ;
PRIVATE>
: construct-ssa ( cfg -- cfg' )
{
[ compute-live-sets ]
[ compute-merge-sets ]
[ compute-defs compute-phi-nodes insert-phi-nodes ]
[ rename ]
[ ]
} cleave ;