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

291 lines
8.3 KiB
Factor
Executable File

! Copyright (C) 2008, 2009 Slava Pestov, Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors locals combinators combinators.short-circuit arrays
fry kernel layouts math namespaces sequences cpu.architecture
math.bitwise classes
compiler.cfg.hats
compiler.cfg.comparisons
compiler.cfg.instructions
compiler.cfg.value-numbering.expressions
compiler.cfg.value-numbering.graph
compiler.cfg.value-numbering.simplify ;
IN: compiler.cfg.value-numbering.rewrite
! Outputs f to mean no change
GENERIC: rewrite* ( insn -- insn/f )
: rewrite ( insn -- insn' )
dup [ number-values ] [ rewrite* ] bi
[ rewrite ] [ ] ?if ;
M: insn rewrite* drop f ;
: ##branch-t? ( insn -- ? )
dup ##compare-imm-branch? [
{
[ cc>> cc/= eq? ]
[ src2>> \ f tag-number eq? ]
} 1&&
] [ 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 = ]
} 1&& ; inline
: tagged>constant ( n -- n' )
tag-bits get neg shift ; inline
: (rewrite-tagged-comparison) ( insn -- src1 src2 cc )
[ src1>> vreg>expr in1>> vn>vreg ]
[ src2>> tagged>constant ]
[ cc>> ]
tri ; inline
GENERIC: rewrite-tagged-comparison ( insn -- insn/f )
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 ] }
{ [ dup rewrite-tagged-comparison? ] [ rewrite-tagged-comparison ] }
[ drop f ]
} cond ;
:: >compare-imm ( insn swap? -- insn' )
insn dst>>
insn src1>>
insn src2>> swap? [ swap ] when vreg>constant
insn cc>> swap? [ swap-cc ] when
i \ ##compare-imm new-insn ; inline
: vreg-small-constant? ( vreg -- ? )
vreg>expr {
[ constant-expr? ]
[ value>> small-enough? ]
} 1&& ;
M: ##compare rewrite*
dup [ src1>> ] [ src2>> ] bi
[ vreg-small-constant? ] bi@ 2array {
{ { f t } [ f >compare-imm ] }
{ { t f } [ t >compare-imm ] }
[ 2drop f ]
} case ;
:: >compare-imm-branch ( insn swap? -- insn' )
insn src1>>
insn src2>> swap? [ swap ] when vreg>constant
insn cc>> swap? [ swap-cc ] when
\ ##compare-imm-branch new-insn ; inline
M: ##compare-branch rewrite*
dup [ src1>> ] [ src2>> ] bi
[ vreg-small-constant? ] bi@ 2array {
{ { f t } [ f >compare-imm-branch ] }
{ { t f } [ t >compare-imm-branch ] }
[ 2drop f ]
} case ;
: rewrite-redundant-comparison? ( insn -- ? )
{
[ src1>> vreg>expr compare-expr? ]
[ src2>> \ f tag-number = ]
[ cc>> { cc= cc/= } memq? ]
} 1&& ; 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 rewrite-tagged-comparison? ] [ rewrite-tagged-comparison ] }
[ drop f ]
} cond ;
: constant-fold? ( insn -- ? )
src1>> vreg>expr constant-expr? ; inline
GENERIC: constant-fold* ( x y insn -- z )
M: ##add-imm constant-fold* drop + ;
M: ##sub-imm constant-fold* drop - ;
M: ##mul-imm constant-fold* drop * ;
M: ##and-imm constant-fold* drop bitand ;
M: ##or-imm constant-fold* drop bitor ;
M: ##xor-imm constant-fold* drop bitxor ;
M: ##shr-imm constant-fold* drop [ cell-bits 2^ wrap ] dip neg shift ;
M: ##sar-imm constant-fold* drop neg shift ;
M: ##shl-imm constant-fold* drop shift ;
: constant-fold ( insn -- insn' )
[ dst>> ]
[ [ src1>> vreg>constant ] [ src2>> ] [ ] tri constant-fold* ] bi
\ ##load-immediate new-insn ; inline
:: new-imm-insn ( insn dst src1 src2 op -- new-insn/insn )
src2 small-enough? [ dst src1 src2 op new-insn ] [ insn ] if ; inline
: reassociate? ( insn -- ? )
[ src1>> vreg>expr op>> ] [ class ] bi = ; inline
: reassociate ( insn op -- insn )
[
{
[ ]
[ dst>> ]
[ src1>> vreg>expr [ in1>> vn>vreg ] [ in2>> vn>constant ] bi ]
[ src2>> ]
[ ]
} cleave constant-fold*
] dip new-imm-insn ; inline
M: ##add-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
{ [ dup reassociate? ] [ \ ##add-imm reassociate ] }
[ drop f ]
} cond ;
: sub-imm>add-imm ( insn -- insn' )
dup [ dst>> ] [ src1>> ] [ src2>> neg ] tri dup small-enough?
[ \ ##add-imm new-insn nip ] [ 2drop 2drop f ] if ;
M: ##sub-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
[ sub-imm>add-imm ]
} cond ;
: strength-reduce-mul ( insn -- insn' )
[ [ dst>> ] [ src1>> ] bi ] [ src2>> log2 ] bi \ ##shl-imm new-insn ;
: strength-reduce-mul? ( insn -- ? )
src2>> power-of-2? ;
M: ##mul-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
{ [ dup strength-reduce-mul? ] [ strength-reduce-mul ] }
{ [ dup reassociate? ] [ \ ##mul-imm reassociate ] }
[ drop f ]
} cond ;
M: ##and-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
{ [ dup reassociate? ] [ \ ##and-imm reassociate ] }
[ drop f ]
} cond ;
M: ##or-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
{ [ dup reassociate? ] [ \ ##or-imm reassociate ] }
[ drop f ]
} cond ;
M: ##xor-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
{ [ dup reassociate? ] [ \ ##xor-imm reassociate ] }
[ drop f ]
} cond ;
M: ##shl-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
[ drop f ]
} cond ;
M: ##shr-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
[ drop f ]
} cond ;
M: ##sar-imm rewrite*
{
{ [ dup constant-fold? ] [ constant-fold ] }
[ drop f ]
} cond ;
:: insn>imm-insn ( insn op swap? -- )
insn
insn dst>>
insn src1>>
insn src2>> swap? [ swap ] when vreg>constant
op new-imm-insn ; inline
: rewrite-arithmetic ( insn op -- ? )
{
{ [ over src2>> vreg-small-constant? ] [ f insn>imm-insn ] }
[ 2drop f ]
} cond ; inline
: rewrite-arithmetic-commutative ( insn op -- ? )
{
{ [ over src2>> vreg-small-constant? ] [ f insn>imm-insn ] }
{ [ over src1>> vreg-small-constant? ] [ t insn>imm-insn ] }
[ 2drop f ]
} cond ; inline
M: ##add rewrite* \ ##add-imm rewrite-arithmetic-commutative ;
: subtraction-identity? ( insn -- ? )
[ src1>> ] [ src2>> ] bi [ vreg>vn ] bi@ eq? ;
: rewrite-subtraction-identity ( insn -- insn' )
dst>> 0 \ ##load-immediate new-insn ;
M: ##sub rewrite*
{
{ [ dup subtraction-identity? ] [ rewrite-subtraction-identity ] }
[ \ ##sub-imm rewrite-arithmetic ]
} cond ;
M: ##mul rewrite* \ ##mul-imm rewrite-arithmetic-commutative ;
M: ##and rewrite* \ ##and-imm rewrite-arithmetic-commutative ;
M: ##or rewrite* \ ##or-imm rewrite-arithmetic-commutative ;
M: ##xor rewrite* \ ##xor-imm rewrite-arithmetic-commutative ;