factor/basis/compiler/cfg/linearization/linearization.factor

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2.4 KiB
Factor
Executable File

! Copyright (C) 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel math accessors sequences namespaces make
combinators classes
compiler.cfg
compiler.cfg.rpo
compiler.cfg.instructions ;
IN: compiler.cfg.linearization
! Convert CFG IR to machine IR.
GENERIC: linearize-insn ( basic-block insn -- )
: linearize-insns ( basic-block -- )
dup instructions>> [ linearize-insn ] with each ; inline
M: insn linearize-insn , drop ;
: useless-branch? ( basic-block successor -- ? )
#! If our successor immediately follows us in RPO, then we
#! don't need to branch.
[ number>> ] bi@ 1- = ; inline
: branch-to-branch? ( successor -- ? )
#! A branch to a block containing just a jump return is cloned.
instructions>> dup length 2 = [
[ first ##epilogue? ]
[ second [ ##return? ] [ ##jump? ] bi or ] bi and
] [ drop f ] if ;
: emit-branch ( basic-block successor -- )
{
{ [ 2dup useless-branch? ] [ 2drop ] }
{ [ dup branch-to-branch? ] [ nip linearize-insns ] }
[ nip number>> _branch ]
} cond ;
M: ##branch linearize-insn
drop dup successors>> first emit-branch ;
: (binary-conditional) ( basic-block insn -- basic-block successor1 successor2 src1 src2 cc )
[ dup successors>> first2 ]
[ [ src1>> ] [ src2>> ] [ cc>> ] tri ] bi* ; inline
: binary-conditional ( basic-block insn -- basic-block successor label2 src1 src2 cc )
[ (binary-conditional) ]
[ drop dup successors>> second useless-branch? ] 2bi
[ [ swap number>> ] 3dip ] [ [ number>> ] 3dip negate-cc ] if ;
M: ##compare-branch linearize-insn
binary-conditional _compare-branch emit-branch ;
M: ##compare-imm-branch linearize-insn
binary-conditional _compare-imm-branch emit-branch ;
M: ##compare-float-branch linearize-insn
binary-conditional _compare-float-branch emit-branch ;
: gc? ( bb -- ? )
instructions>> [
class {
##allot
##integer>bignum
##box-float
##box-alien
} memq?
] any? ;
: linearize-basic-block ( bb -- )
[ number>> _label ]
[ gc? [ _gc ] when ]
[ linearize-insns ]
tri ;
: linearize-basic-blocks ( rpo -- insns )
[ [ linearize-basic-block ] each ] { } make ;
: build-mr ( cfg -- mr )
[ entry>> reverse-post-order linearize-basic-blocks ]
[ word>> ] [ label>> ]
tri <mr> ;