         n len + b' nth-unsafe n 2 * 1 + c' set-nth-unsafe
     ] each
     c' underlying>> ;
-: (simd-v<=)               ( a b rep -- c )
+SIMD-INTRINSIC: (simd-v<=)               ( a b rep -- c )
     dup rep-tf-values '[ <= _ _ ? ] components-2map ; 
-: (simd-v<)                ( a b rep -- c )
+SIMD-INTRINSIC: (simd-v<)                ( a b rep -- c )
     dup rep-tf-values '[ <  _ _ ? ] components-2map ;
-: (simd-v=)                ( a b rep -- c )
+SIMD-INTRINSIC: (simd-v=)                ( a b rep -- c )
     dup rep-tf-values '[ =  _ _ ? ] components-2map ;
-: (simd-v>)                ( a b rep -- c )
+SIMD-INTRINSIC: (simd-v>)                ( a b rep -- c )
     dup rep-tf-values '[ >  _ _ ? ] components-2map ;
-: (simd-v>=)               ( a b rep -- c )
+SIMD-INTRINSIC: (simd-v>=)               ( a b rep -- c )
     dup rep-tf-values '[ >= _ _ ? ] components-2map ;
-: (simd-vunordered?)       ( a b rep -- c )
+SIMD-INTRINSIC: (simd-vunordered?)       ( a b rep -- c )
     dup rep-tf-values '[ unordered? _ _ ? ] components-2map ;
-: (simd-vany?)             ( a   rep -- ? ) [ bitor  ] bitwise-components-reduce zero? not ;
-: (simd-vall?)             ( a   rep -- ? ) [ bitand ] bitwise-components-reduce zero? not ;
-: (simd-vnone?)            ( a   rep -- ? ) [ bitor  ] bitwise-components-reduce zero?     ;
-: (simd-v>float)           ( a   rep -- c )
+SIMD-INTRINSIC: (simd-vany?)             ( a   rep -- ? ) [ bitor  ] bitwise-components-reduce zero? not ;
+SIMD-INTRINSIC: (simd-vall?)             ( a   rep -- ? ) [ bitand ] bitwise-components-reduce zero? not ;
+SIMD-INTRINSIC: (simd-vnone?)            ( a   rep -- ? ) [ bitor  ] bitwise-components-reduce zero?     ;
+SIMD-INTRINSIC: (simd-v>float)           ( a   rep -- c )
     [ >rep-array [ >float ] ] [ >float-vector-rep <rep-array> ] bi map-as underlying>> ;
-: (simd-v>integer)         ( a   rep -- c )
+SIMD-INTRINSIC: (simd-v>integer)         ( a   rep -- c )
     [ >rep-array [ >integer ] ] [ >int-vector-rep <rep-array> ] bi map-as underlying>> ;
-: (simd-vpack-signed)      ( a b rep -- c )
+SIMD-INTRINSIC: (simd-vpack-signed)      ( a b rep -- c )
     [ 2>rep-array cord-append ]
     [ narrow-vector-rep [ <rep-array> ] [ rep-component-type ] bi ] bi
     '[ _ c-type-clamp ] swap map-as underlying>> ;
-: (simd-vpack-unsigned)    ( a b rep -- c )
+SIMD-INTRINSIC: (simd-vpack-unsigned)    ( a b rep -- c )
     [ 2>rep-array cord-append ]
     [ narrow-vector-rep >uint-vector-rep [ <rep-array> ] [ rep-component-type ] bi ] bi
     '[ _ c-type-clamp ] swap map-as underlying>> ;
-: (simd-vunpack-head)      ( a   rep -- c ) 
+SIMD-INTRINSIC: (simd-vunpack-head)      ( a   rep -- c ) 
     [ >rep-array ] [ widen-vector-rep [ rep-length ] [ [>rep-array] ] bi ] bi
     [ head-slice ] dip call( a' -- c' ) underlying>> ;
-: (simd-vunpack-tail)      ( a   rep -- c )
+SIMD-INTRINSIC: (simd-vunpack-tail)      ( a   rep -- c )
     [ >rep-array ] [ widen-vector-rep [ rep-length ] [ [>rep-array] ] bi ] bi
     [ tail-slice ] dip call( a' -- c' ) underlying>> ;
-: (simd-with)              (   n rep -- v )
+SIMD-INTRINSIC: (simd-with)              (   n rep -- v )
     [ rep-length swap '[ _ ] ] [ <rep-array> ] bi replicate-as 
     underlying>> ;
-: (simd-gather-2)          ( m n rep -- v ) <rep-array> [ 2 set-firstn ] keep underlying>> ;
-: (simd-gather-4)          ( m n o p rep -- v ) <rep-array> [ 4 set-firstn ] keep underlying>> ;
-: (simd-select)            ( a n rep -- x ) [ swap ] dip >rep-array nth-unsafe ;
-
-: alien-vector     (       c-ptr n rep -- value )
+SIMD-INTRINSIC: (simd-gather-2)          ( m n rep -- v ) <rep-array> [ 2 set-firstn ] keep underlying>> ;
+SIMD-INTRINSIC: (simd-gather-4)          ( m n o p rep -- v ) <rep-array> [ 4 set-firstn ] keep underlying>> ;
+SIMD-INTRINSIC: (simd-select)            ( a n rep -- x ) [ swap ] dip >rep-array nth-unsafe ;
+
+SIMD-INTRINSIC: alien-vector     (       c-ptr n rep -- value )
     [ swap <displaced-alien> ] dip rep-size memory>byte-array ;
-: set-alien-vector ( value c-ptr n rep --       )
+SIMD-INTRINSIC: set-alien-vector ( value c-ptr n rep --       )
     [ swap <displaced-alien> swap ] dip rep-size memcpy ;
 
 "compiler.cfg.intrinsics.simd" require

        [ [ second ] bi@ * ] 2bi +
        wide-type c-type-clamp
    ] wide-rep <rep-array> 2map-as underlying>> ;
: (simd-v/)                ( a b rep -- c ) [ / ] components-2map ;
: (simd-vavg)              ( a b rep -- c )
    [ + dup integer? [ 1 + -1 shift ] [ 0.5 * ] if ] components-2map ;
: (simd-vmin)              ( a b rep -- c ) [ min ] components-2map ;
: (simd-vmax)              ( a b rep -- c ) [ max ] components-2map ;
: (simd-v.)                ( a b rep -- n )
    [ 2>rep-array [ [ first ] bi@ * ] 2keep ] keep
    1 swap rep-length [a,b) [ '[ _ swap nth-unsafe ] bi@ * + ] with with each ;
: (simd-vsqrt)             ( a   rep -- c ) [ fsqrt ] components-map ;
: (simd-vsad)              ( a b rep -- c ) 2>rep-array [ - abs ] [ + ] 2map-reduce ;
: (simd-sum)               ( a   rep -- n ) [ + ] components-reduce ;
: (simd-vabs)              ( a   rep -- c ) [ abs ] components-map ;
: (simd-vbitand)           ( a b rep -- c ) [ bitand ] bitwise-components-2map ;
: (simd-vbitandn)          ( a b rep -- c ) [ [ bitnot ] dip bitand ] bitwise-components-2map ;
: (simd-vbitor)            ( a b rep -- c ) [ bitor ] bitwise-components-2map ;
: (simd-vbitxor)           ( a b rep -- c ) [ bitxor ] bitwise-components-2map ;
: (simd-vbitnot)           ( a   rep -- c ) [ bitnot ] bitwise-components-map ;
: (simd-vand)              ( a b rep -- c ) [ bitand ] bitwise-components-2map ;
: (simd-vandn)             ( a b rep -- c ) [ [ bitnot ] dip bitand ] bitwise-components-2map ;
: (simd-vor)               ( a b rep -- c ) [ bitor ] bitwise-components-2map ;
: (simd-vxor)              ( a b rep -- c ) [ bitxor ] bitwise-components-2map ;
: (simd-vnot)              ( a   rep -- c ) [ bitnot ] bitwise-components-map ;
: (simd-vlshift)           ( a n rep -- c ) swap '[ _ shift ] bitwise-components-map ;
: (simd-vrshift)           ( a n rep -- c ) swap '[ _ neg shift ] bitwise-components-map ;
: (simd-hlshift)           ( a n rep -- c )
    drop head-slice* 16 0 pad-head ;
: (simd-hrshift)           ( a n rep -- c )
    drop tail-slice 16 0 pad-tail ;
: (simd-vshuffle-elements) ( a n rep -- c ) [ rep-length 0 pad-tail ] keep (vshuffle) ;
: (simd-vshuffle2-elements) ( a b n rep -- c ) [ rep-length 0 pad-tail ] keep (vshuffle2) ;
: (simd-vshuffle-bytes)    ( a b rep -- c ) drop uchar-16-rep (vshuffle) ;
:: (simd-vmerge-head)      ( a b rep -- c )
    a b rep 2>rep-array :> ( a' b' )
    rep <rep-array> :> c'
    rep rep-length 2 /i iota [| n |

        n b' nth-unsafe n 2 * 1 + c' set-nth-unsafe
    ] each
    c' underlying>> ;
SIMD-INTRINSIC:: (simd-vmerge-tail)      ( a b rep -- c )
    a b rep 2>rep-array :> ( a' b' )
    rep <rep-array> :> c'
    rep rep-length 2 /i :> len
