factor/basis/compiler/cfg/value-numbering/rewrite/rewrite.factor

132 lines
4.0 KiB
Factor

! Copyright (C) 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel sequences layouts accessors combinators namespaces
math fry
compiler.cfg.hats
compiler.cfg.instructions
compiler.cfg.value-numbering.graph
compiler.cfg.value-numbering.simplify
compiler.cfg.value-numbering.expressions ;
IN: compiler.cfg.value-numbering.rewrite
GENERIC: rewrite ( insn -- insn' )
M: ##mul-imm rewrite
dup src2>> dup power-of-2? [
[ [ dst>> ] [ src1>> ] bi ] [ log2 ] bi* \ ##shl-imm new-insn
dup number-values
] [ drop ] if ;
: ##branch-t? ( insn -- ? )
dup ##compare-imm-branch? [
[ cc>> cc/= eq? ]
[ src2>> \ f tag-number eq? ] bi and
] [ drop f ] if ; inline
: rewrite-boolean-comparison? ( insn -- ? )
dup ##branch-t? [
src1>> vreg>expr compare-expr?
] [ drop f ] if ; inline
: >compare-expr< ( expr -- in1 in2 cc )
[ in1>> vn>vreg ] [ in2>> vn>vreg ] [ cc>> ] tri ; inline
: >compare-imm-expr< ( expr -- in1 in2 cc )
[ in1>> vn>vreg ] [ in2>> vn>constant ] [ cc>> ] tri ; inline
: rewrite-boolean-comparison ( expr -- insn )
src1>> vreg>expr dup op>> {
{ \ ##compare [ >compare-expr< \ ##compare-branch new-insn ] }
{ \ ##compare-imm [ >compare-imm-expr< \ ##compare-imm-branch new-insn ] }
{ \ ##compare-float [ >compare-expr< \ ##compare-float-branch new-insn ] }
} case ;
: tag-fixnum-expr? ( expr -- ? )
dup op>> \ ##shl-imm eq?
[ in2>> vn>constant tag-bits get = ] [ drop f ] if ;
: rewrite-tagged-comparison? ( insn -- ? )
#! Are we comparing two tagged fixnums? Then untag them.
[ src1>> vreg>expr tag-fixnum-expr? ]
[ src2>> tag-mask get bitand 0 = ]
bi and ; inline
: (rewrite-tagged-comparison) ( insn -- src1 src2 cc )
[ src1>> vreg>expr in1>> vn>vreg ]
[ src2>> tag-bits get neg shift ]
[ cc>> ]
tri ; inline
GENERIC: rewrite-tagged-comparison ( insn -- insn' )
M: ##compare-imm-branch rewrite-tagged-comparison
(rewrite-tagged-comparison) \ ##compare-imm-branch new-insn ;
M: ##compare-imm rewrite-tagged-comparison
[ dst>> ] [ (rewrite-tagged-comparison) ] bi
i \ ##compare-imm new-insn ;
M: ##compare-imm-branch rewrite
dup rewrite-boolean-comparison? [ rewrite-boolean-comparison ] when
dup ##compare-imm-branch? [
dup rewrite-tagged-comparison? [ rewrite-tagged-comparison ] when
] when ;
: flip-comparison? ( insn -- ? )
dup cc>> cc= eq? [ src1>> vreg>expr constant-expr? ] [ drop f ] if ;
: flip-comparison ( insn -- insn' )
[ dst>> ]
[ src2>> ]
[ src1>> vreg>vn vn>constant ] tri
cc= f i \ ##compare-imm boa ;
M: ##compare rewrite
dup flip-comparison? [
flip-comparison
dup number-values
rewrite
] when ;
: rewrite-redundant-comparison? ( insn -- ? )
[ src1>> vreg>expr compare-expr? ]
[ src2>> \ f tag-number = ]
[ cc>> { cc= cc/= } memq? ]
tri and and ; inline
: rewrite-redundant-comparison ( insn -- insn' )
[ cc>> ] [ dst>> ] [ src1>> vreg>expr dup op>> ] tri {
{ \ ##compare [ >compare-expr< i \ ##compare new-insn ] }
{ \ ##compare-imm [ >compare-imm-expr< i \ ##compare-imm new-insn ] }
{ \ ##compare-float [ >compare-expr< i \ ##compare-float new-insn ] }
} case
swap cc= eq? [ [ negate-cc ] change-cc ] when ;
M: ##compare-imm rewrite
dup rewrite-redundant-comparison? [
rewrite-redundant-comparison
dup number-values rewrite
] when
dup ##compare-imm? [
dup rewrite-tagged-comparison? [
rewrite-tagged-comparison
dup number-values rewrite
] when
] when ;
: dispatch-offset ( expr -- n )
[ in2>> vn>constant tag-bits get neg shift ] [ op>> ] bi
\ ##sub-imm eq? [ neg ] when ;
: add-dispatch-offset? ( insn -- expr ? )
src>> vreg>expr dup op>> { ##add-imm ##sub-imm } memq? ; inline
M: ##dispatch rewrite
dup add-dispatch-offset? [
[ clone ] dip
[ in1>> vn>vreg >>src ]
[ dispatch-offset '[ _ + ] change-offset ] bi
] [ drop ] if ;
M: insn rewrite ;