Merge branch 'master' into new_optimizer

basis/alien/c-types/c-types-tests.factor

@@ -2,6 +2,12 @@ IN: alien.c-types.tests
 USING: alien alien.syntax alien.c-types kernel tools.test
 sequences system libc alien.strings io.encodings.utf8 ;
 
+\ expand-constants must-infer
+
+: xyz 123 ;
+
+[ { "blah" 123 } ] [ { "blah" xyz } expand-constants ] unit-test
+
 : foo ( -- n ) "fdafd" f dlsym [ 123 ] unless* ;
 
 [ 123 ] [ foo ] unit-test

basis/alien/c-types/c-types.factor

@@ -4,7 +4,7 @@ USING: byte-arrays arrays assocs kernel kernel.private libc math
 namespaces parser sequences strings words assocs splitting
 math.parser cpu.architecture alien alien.accessors quotations
 layouts system compiler.units io.files io.encodings.binary
-accessors combinators effects ;
+accessors combinators effects continuations ;
 IN: alien.c-types
 
 DEFER: <int>
@@ -239,15 +239,20 @@ M: long-long-type box-return ( type -- )
     } 2cleave ;
 
 : expand-constants ( c-type -- c-type' )
-    #! We use def>> call instead of execute to get around
-    #! staging violations
     dup array? [
-        unclip >r [ dup word? [ def>> call ] when ] map r> prefix
+        unclip >r [
+            dup word? [
+                def>> { } swap with-datastack first
+            ] when
+        ] map r> prefix
     ] when ;
 
 : malloc-file-contents ( path -- alien len )
     binary file-contents dup malloc-byte-array swap length ;
 
+: if-void ( type true false -- )
+    pick "void" = [ drop nip call ] [ nip call ] if ; inline
+
 [
     <c-type>
         [ alien-cell ] >>getter

basis/compiler/generator/generator.factor

@@ -2,8 +2,10 @@
 ! See http://factorcode.org/license.txt for BSD license.
 USING: accessors arrays assocs classes combinators
 cpu.architecture effects generic hashtables io kernel
-kernel.private layouts math namespaces prettyprint quotations
-sequences system threads words vectors sets dequeues cursors
+kernel.private layouts math math.parser namespaces prettyprint
+quotations sequences system threads words vectors sets dequeues
+cursors continuations.private summary alien alien.c-types
+alien.structs alien.strings alien.arrays libc compiler.errors
 stack-checker.inlining
 compiler.tree compiler.tree.builder compiler.tree.combinators
 compiler.tree.propagation.info compiler.generator.fixup
@@ -48,7 +50,7 @@ SYMBOL: current-label-start
 : save-machine-code ( literals relocation labels code -- )
     4array compiling-label get compiled get set-at ;
 
-: with-generator ( node word label quot -- )
+: with-generator ( nodes word label quot -- )
     [
         >r begin-compiling r>
         { } make fixup
@@ -267,3 +269,316 @@ M: #return-recursive generate-node
     end-basic-block
     label>> id>> compiling-loops get key?
     [ %return ] unless f ;
+
+! #alien-invoke
+: large-struct? ( ctype -- ? )
+    dup c-struct? [
+        heap-size struct-small-enough? not
+    ] [ drop f ] if ;
+
+: alien-parameters ( params -- seq )
+    dup parameters>>
+    swap return>> large-struct? [ "void*" prefix ] when ;
+
+: alien-return ( params -- ctype )
+    return>> dup large-struct? [ drop "void" ] when ;
+
+: c-type-stack-align ( type -- align )
+    dup c-type-stack-align? [ c-type-align ] [ drop cell ] if ;
+
+: parameter-align ( n type -- n delta )
+    over >r c-type-stack-align align dup r> - ;
+
+: parameter-sizes ( types -- total offsets )
+    #! Compute stack frame locations.
+    [
+        0 [
+            [ parameter-align drop dup , ] keep stack-size +
+        ] reduce cell align
+    ] { } make ;
+
+: return-size ( ctype -- n )
+    #! Amount of space we reserve for a return value.
+    dup large-struct? [ heap-size ] [ drop 0 ] if ;
+
+: alien-stack-frame ( params -- n )
+    alien-parameters parameter-sizes drop ;
+
+: alien-invoke-frame ( params -- n )
+    #! One cell is temporary storage, temp@
+    dup return>> return-size
+    swap alien-stack-frame +
+    cell + ;
+
+: set-stack-frame ( n -- )
+    dup [ frame-required ] when* \ stack-frame set ;
+
+: with-stack-frame ( n quot -- )
+    swap set-stack-frame
+    call
+    f set-stack-frame ; inline
+
+GENERIC: reg-size ( register-class -- n )
+
+M: int-regs reg-size drop cell ;
+
+M: single-float-regs reg-size drop 4 ;
+
+M: double-float-regs reg-size drop 8 ;
+
+GENERIC: reg-class-variable ( register-class -- symbol )
+
+M: reg-class reg-class-variable ;
+
+M: float-regs reg-class-variable drop float-regs ;
+
+GENERIC: inc-reg-class ( register-class -- )
+
+M: reg-class inc-reg-class
+    dup reg-class-variable inc
+    fp-shadows-int? [ reg-size stack-params +@ ] [ drop ] if ;
+
+M: float-regs inc-reg-class
+    dup call-next-method
+    fp-shadows-int? [ reg-size cell /i int-regs +@ ] [ drop ] if ;
+
+: reg-class-full? ( class -- ? )
+    [ reg-class-variable get ] [ param-regs length ] bi >= ;
+
+: spill-param ( reg-class -- n reg-class )
+    stack-params get
+    >r reg-size stack-params +@ r>
+    stack-params ;
+
+: fastcall-param ( reg-class -- n reg-class )
+    [ reg-class-variable get ] [ inc-reg-class ] [ ] tri ;
+
+: alloc-parameter ( parameter -- reg reg-class )
+    c-type-reg-class dup reg-class-full?
+    [ spill-param ] [ fastcall-param ] if
+    [ param-reg ] keep ;
+
+: (flatten-int-type) ( size -- )
+    cell /i "void*" c-type <repetition> % ;
+
+GENERIC: flatten-value-type ( type -- )
+
+M: object flatten-value-type , ;
+
+M: struct-type flatten-value-type ( type -- )
+    stack-size cell align (flatten-int-type) ;
+
+M: long-long-type flatten-value-type ( type -- )
+    stack-size cell align (flatten-int-type) ;
+
+: flatten-value-types ( params -- params )
+    #! Convert value type structs to consecutive void*s.
+    [
+        0 [
+            c-type
+            [ parameter-align (flatten-int-type) ] keep
+            [ stack-size cell align + ] keep
+            flatten-value-type
+        ] reduce drop
+    ] { } make ;
+
+: each-parameter ( parameters quot -- )
+    >r [ parameter-sizes nip ] keep r> 2each ; inline
+
+: reverse-each-parameter ( parameters quot -- )
+    >r [ parameter-sizes nip ] keep r> 2reverse-each ; inline
+
+: reset-freg-counts ( -- )
+    { int-regs float-regs stack-params } [ 0 swap set ] each ;
+
+: with-param-regs ( quot -- )
+    #! In quot you can call alloc-parameter
+    [ reset-freg-counts call ] with-scope ; inline
+
+: move-parameters ( node word -- )
+    #! Moves values from C stack to registers (if word is
+    #! %load-param-reg) and registers to C stack (if word is
+    #! %save-param-reg).
+    >r
+    alien-parameters
+    flatten-value-types
+    r> [ >r alloc-parameter r> execute ] curry each-parameter ;
+    inline
+
+: unbox-parameters ( offset node -- )
+    parameters>> [
+        %prepare-unbox >r over + r> unbox-parameter
+    ] reverse-each-parameter drop ;
+
+: prepare-box-struct ( node -- offset )
+    #! Return offset on C stack where to store unboxed
+    #! parameters. If the C function is returning a structure,
+    #! the first parameter is an implicit target area pointer,
+    #! so we need to use a different offset.
+    return>> dup large-struct?
+    [ heap-size %prepare-box-struct cell ] [ drop 0 ] if ;
+
+: objects>registers ( params -- )
+    #! Generate code for unboxing a list of C types, then
+    #! generate code for moving these parameters to register on
+    #! architectures where parameters are passed in registers.
+    [
+        [ prepare-box-struct ] keep
+        [ unbox-parameters ] keep
+        \ %load-param-reg move-parameters
+    ] with-param-regs ;
+
+: box-return* ( node -- )
+    return>> [ ] [ box-return ] if-void ;
+
+TUPLE: no-such-library name ;
+
+M: no-such-library summary
+    drop "Library not found" ;
+
+M: no-such-library compiler-error-type
+    drop +linkage+ ;
+
+: no-such-library ( name -- )
+    \ no-such-library boa
+    compiling-word get compiler-error ;
+
+TUPLE: no-such-symbol name ;
+
+M: no-such-symbol summary
+    drop "Symbol not found" ;
+
+M: no-such-symbol compiler-error-type
+    drop +linkage+ ;
+
+: no-such-symbol ( name -- )
+    \ no-such-symbol boa
+    compiling-word get compiler-error ;
+
+: check-dlsym ( symbols dll -- )
+    dup dll-valid? [
+        dupd [ dlsym ] curry contains?
+        [ drop ] [ no-such-symbol ] if
+    ] [
+        dll-path no-such-library drop
+    ] if ;
+
+: stdcall-mangle ( symbol node -- symbol )
+    "@"
+    swap parameters>> parameter-sizes drop
+    number>string 3append ;
+
+: alien-invoke-dlsym ( params -- symbols dll )
+    dup function>> dup pick stdcall-mangle 2array
+    swap library>> library dup [ dll>> ] when
+    2dup check-dlsym ;
+
+M: #alien-invoke generate-node
+    params>>
+    dup alien-invoke-frame [
+        end-basic-block
+        %prepare-alien-invoke
+        dup objects>registers
+        %prepare-var-args
+        dup alien-invoke-dlsym %alien-invoke
+        dup %cleanup
+        box-return*
+        iterate-next
+    ] with-stack-frame ;
+
+! #alien-indirect
+M: #alien-indirect generate-node
+    params>>
+    dup alien-invoke-frame [
+        ! Flush registers
+        end-basic-block
+        ! Save registers for GC
+        %prepare-alien-invoke
+        ! Save alien at top of stack to temporary storage
+        %prepare-alien-indirect
+        dup objects>registers
+        %prepare-var-args
+        ! Call alien in temporary storage
+        %alien-indirect
+        dup %cleanup
+        box-return*
+        iterate-next
+    ] with-stack-frame ;
+
+! #alien-callback
+: box-parameters ( params -- )
+    alien-parameters [ box-parameter ] each-parameter ;
+
+: registers>objects ( node -- )
+    [
+        dup \ %save-param-reg move-parameters
+        "nest_stacks" f %alien-invoke
+        box-parameters
+    ] with-param-regs ;
+
+TUPLE: callback-context ;
+
+: current-callback 2 getenv ;
+
+: wait-to-return ( token -- )
+    dup current-callback eq? [
+        drop
+    ] [
+        yield wait-to-return
+    ] if ;
+
+: do-callback ( quot token -- )
+    init-catchstack
+    dup 2 setenv
+    slip
+    wait-to-return ; inline
+
+: callback-return-quot ( ctype -- quot )
+    return>> {
+        { [ dup "void" = ] [ drop [ ] ] }
+        { [ dup large-struct? ] [ heap-size [ memcpy ] curry ] }
+        [ c-type c-type-unboxer-quot ]
+    } cond ;
+
+: callback-prep-quot ( params -- quot )
+    parameters>> [ c-type c-type-boxer-quot ] map spread>quot ;
+
+: wrap-callback-quot ( params -- quot )
+    [
+        [ callback-prep-quot ]
+        [ quot>> ]
+        [ callback-return-quot ] tri 3append ,
+        [ callback-context new do-callback ] %
+    ] [ ] make ;
+
+: %unnest-stacks ( -- ) "unnest_stacks" f %alien-invoke ;
+
+: callback-unwind ( params -- n )
+    {
+        { [ dup abi>> "stdcall" = ] [ alien-stack-frame ] }
+        { [ dup return>> large-struct? ] [ drop 4 ] }
+        [ drop 0 ]
+    } cond ;
+
+: %callback-return ( params -- )
+    #! All the extra book-keeping for %unwind is only for x86.
+    #! On other platforms its an alias for %return.
+    dup alien-return
+    [ %unnest-stacks ] [ %callback-value ] if-void
+    callback-unwind %unwind ;
+
+: generate-callback ( params -- )
+    dup xt>> dup [
+        init-templates
+        %prologue-later
+        dup alien-stack-frame [
+            [ registers>objects ]
+            [ wrap-callback-quot %alien-callback ]
+            [ %callback-return ]
+            tri
+        ] with-stack-frame
+    ] with-generator ;
+
+M: #alien-callback generate-node
+    end-basic-block
+    params>> generate-callback iterate-next ;

basis/compiler/tree/dataflow-analysis/backward/backward.factor

@@ -35,6 +35,12 @@ M: #phi backward
     [ [ out-r>> ] [ phi-in-r>> ] bi look-at-corresponding ]
     2bi ;
 
+M: #alien-invoke backward
+    nip [ look-at-inputs ] [ look-at-outputs ] bi ;
+
+M: #alien-indirect backward
+    nip [ look-at-inputs ] [ look-at-outputs ] bi ;
+
 M: node backward 2drop ;
 
 : backward-dfa ( node quot -- assoc ) [ backward ] dfa ; inline

basis/compiler/tree/dead-code/dead-code.factor

@@ -23,6 +23,12 @@ M: #call mark-live-values
     dup word>> "flushable" word-prop
     [ drop ] [ [ look-at-inputs ] [ look-at-outputs ] bi ] if ;
 
+M: #alien-invoke mark-live-values
+    [ look-at-inputs ] [ look-at-outputs ] bi ;
+
+M: #alien-indirect mark-live-values
+    [ look-at-inputs ] [ look-at-outputs ] bi ;
+
 M: #return mark-live-values
     look-at-inputs ;
 

basis/compiler/tree/debugger/debugger-tests.factor

@@ -1,6 +1,5 @@
 IN: compiler.tree.debugger.tests
 USING: compiler.tree.debugger tools.test ;
 
-\ optimized-quot. must-infer
-\ optimized-word. must-infer
+\ optimized. must-infer
 \ optimizer-report. must-infer

basis/compiler/tree/debugger/debugger.factor

@@ -22,7 +22,7 @@ MACRO: match-choose ( alist -- )
 MATCH-VARS: ?a ?b ?c ;
 
 : pretty-shuffle ( effect -- word/f )
-    [ in>> ] [ out>> ] bi {
+    [ in>> ] [ out>> ] bi 2array {
         { { { } { } } [ ] }
         { { { ?a } { ?a } } [ ] }
         { { { ?a ?b } { ?a ?b } } [ ] }

basis/compiler/tree/escape-analysis/simple/simple.factor

@@ -80,3 +80,13 @@ M: #call escape-analysis*
 
 M: #return escape-analysis*
     in-d>> add-escaping-values ;
+
+M: #alien-invoke escape-analysis*
+    [ in-d>> add-escaping-values ]
+    [ out-d>> unknown-allocation ]
+    bi ;
+
+M: #alien-indirect escape-analysis*
+    [ in-d>> add-escaping-values ]
+    [ out-d>> unknown-allocation ]
+    bi ;

basis/compiler/tree/propagation/simple/simple.factor

@@ -115,3 +115,9 @@ M: #call propagate-before
 M: #call propagate-after
     dup word>> "input-classes" word-prop dup
     [ propagate-input-classes ] [ 2drop ] if ;
+
+M: #alien-invoke propagate-before
+    out-d>> [ object-info swap set-value-info ] each ;
+
+M: #alien-indirect propagate-before
+    out-d>> [ object-info swap set-value-info ] each ;

basis/compiler/tree/tree.factor

@@ -143,6 +143,30 @@ TUPLE: #copy < #renaming in-d out-d ;
         swap >>out-d
         swap >>in-d ;
 
+TUPLE: #alien-node < node params ;
+
+: new-alien-node ( params class -- node )
+    new
+        over in-d>> >>in-d
+        over out-d>> >>out-d
+        swap >>params ; inline
+
+TUPLE: #alien-invoke < #alien-node in-d out-d ;
+
+: #alien-invoke ( params -- node )
+    \ #alien-invoke new-alien-node ;
+
+TUPLE: #alien-indirect < #alien-node in-d out-d ;
+
+: #alien-indirect ( params -- node )
+    \ #alien-indirect new-alien-node ;
+
+TUPLE: #alien-callback < #alien-node ;
+
+: #alien-callback ( params -- node )
+    \ #alien-callback new
+        swap >>params ;
+
 : node, ( node -- ) stack-visitor get push ;
 
 GENERIC: inputs/outputs ( #renaming -- inputs outputs )
@@ -177,3 +201,6 @@ M: vector #phi, #phi node, ;
 M: vector #declare, #declare node, ;
 M: vector #recursive, #recursive node, ;
 M: vector #copy, #copy node, ;
+M: vector #alien-invoke, #alien-invoke node, ;
+M: vector #alien-indirect, #alien-indirect node, ;
+M: vector #alien-callback, #alien-callback node, ;

basis/compiler/tree/tuple-unboxing/tuple-unboxing.factor

@@ -128,4 +128,8 @@ M: #return unbox-tuples* dup in-d>> assert-not-unboxed ;
 
 M: #introduce unbox-tuples* dup value>> assert-not-unboxed ;
 
+M: #alien-invoke unbox-tuples* dup in-d>> assert-not-unboxed ;
+
+M: #alien-indirect unbox-tuples* dup in-d>> assert-not-unboxed ;
+
 : unbox-tuples ( nodes -- nodes ) [ unbox-tuples* ] map-nodes ;

basis/stack-checker/inlining/inlining.factor

@@ -32,7 +32,7 @@ M: inline-recursive hashcode* id>> hashcode* ;
 
 : <inline-recursive> ( word -- label )
     inline-recursive new
-        gensym t "inlined-block" set-word-prop >>id
+        gensym dup t "inlined-block" set-word-prop >>id
         swap >>word ;
 
 : quotation-param? ( obj -- ? )

basis/stack-checker/known-words/known-words.factor

@@ -10,10 +10,14 @@ sequences sequences.private slots.private strings
 strings.private system threads.private classes.tuple
 classes.tuple.private vectors vectors.private words definitions
 words.private assocs summary compiler.units system.private
-combinators locals.backend stack-checker.state
-stack-checker.backend stack-checker.branches
-stack-checker.errors stack-checker.transforms
-stack-checker.visitor ;
+combinators locals.backend
+stack-checker.state
+stack-checker.backend
+stack-checker.branches
+stack-checker.errors
+stack-checker.transforms
+stack-checker.visitor
+stack-checker.alien ;
 IN: stack-checker.known-words
 
 : infer-primitive ( word -- )
@@ -153,13 +157,15 @@ M: object infer-call*
         { \ get-local [ infer-get-local ] }
         { \ drop-locals [ infer-drop-locals ] }
         { \ do-primitive [ \ do-primitive cannot-infer-effect ] }
+        { \ alien-invoke [ infer-alien-invoke ] }
+        { \ alien-indirect [ infer-alien-indirect ] }
+        { \ alien-callback [ infer-alien-callback ] }
     } case ;
 
 {
-    >r r> declare call curry compose
-    execute if dispatch <tuple-boa>
-    (throw) load-locals get-local drop-locals
-    do-primitive
+    >r r> declare call curry compose execute if dispatch
+    <tuple-boa> (throw) load-locals get-local drop-locals
+    do-primitive alien-invoke alien-indirect alien-callback
 } [ t +special+ set-word-prop ] each
 
 { call execute dispatch load-locals get-local drop-locals }
@@ -173,10 +179,10 @@ SYMBOL: +primitive+
         { [ dup +shuffle+ word-prop ] [ infer-shuffle-word ] }
         { [ dup +special+ word-prop ] [ infer-special ] }
         { [ dup +primitive+ word-prop ] [ infer-primitive ] }
-        { [ dup +cannot-infer+ word-prop ] [ cannot-infer-effect ] }
         { [ dup +transform-quot+ word-prop ] [ apply-transform ] }
-        { [ dup +inferred-effect+ word-prop ] [ cached-infer ] }
         { [ dup "macro" word-prop ] [ apply-macro ] }
+        { [ dup +cannot-infer+ word-prop ] [ cannot-infer-effect ] }
+        { [ dup +inferred-effect+ word-prop ] [ cached-infer ] }
         { [ dup recursive-label ] [ call-recursive-word ] }
         [ dup infer-word apply-word/effect ]
     } cond ;

basis/stack-checker/transforms/transforms.factor

@@ -23,10 +23,11 @@ SYMBOL: +transform-n+
     inline
 
 : (apply-transform) ( word quot n -- )
-    consume-d dup [ known literal? ] all? [
+    dup ensure-d [ known literal? ] all? [
         dup empty? [
             drop recursive-state get 1array
         ] [
+            consume-d
             [ #drop, ]
             [ [ literal value>> ] map ]
             [ first literal recursion>> ] tri prefix
@@ -123,7 +124,6 @@ SYMBOL: +transform-n+
 
 : bit-member-quot ( seq -- newquot )
     [
-        [ drop ] % ! drop the sequence itself; we don't use it at run time
         bit-member-seq ,
         [
             {
@@ -140,7 +140,7 @@ SYMBOL: +transform-n+
         bit-member-quot
     ] [
         [ literalize [ t ] ] { } map>assoc
-        [ drop f ] suffix [ nip case ] curry
+        [ drop f ] suffix [ case ] curry
     ] if ;
 
 \ member? [

basis/stack-checker/visitor/dummy/dummy.factor

@@ -22,3 +22,6 @@ M: f #declare, drop ;
 M: f #recursive, 2drop 2drop ;
 M: f #copy, 2drop ;
 M: f #drop, drop ;
+M: f #alien-invoke, drop ;
+M: f #alien-indirect, drop ;
+M: f #alien-callback, drop ;

basis/stack-checker/visitor/visitor.factor

@@ -27,3 +27,6 @@ HOOK: #enter-recursive, stack-visitor ( label inputs outputs -- )
 HOOK: #return-recursive, stack-visitor ( label inputs outputs -- )
 HOOK: #recursive, stack-visitor ( word label inputs visitor -- )
 HOOK: #copy, stack-visitor ( inputs outputs -- )
+HOOK: #alien-invoke, stack-visitor ( params -- )
+HOOK: #alien-indirect, stack-visitor ( params -- )
+HOOK: #alien-callback, stack-visitor ( params -- )

unfinished/stack-checker/alien/alien.factor

@@ -0,0 +1,84 @@
+! Copyright (C) 2008 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: kernel sequences accessors combinators math namespaces
+init sets words
+alien alien.c-types
+stack-checker.backend stack-checker.errors stack-checker.visitor ;
+IN: stack-checker.alien
+
+TUPLE: alien-node-params return parameters abi in-d out-d ;
+
+TUPLE: alien-invoke-params < alien-node-params library function ;
+
+TUPLE: alien-indirect-params < alien-node-params ;
+
+TUPLE: alien-callback-params < alien-node-params quot xt ;
+
+: pop-parameters ( -- seq )
+    pop-literal nip [ expand-constants ] map ;
+
+: param-prep-quot ( node -- quot )
+    parameters>> [ c-type c-type-unboxer-quot ] map spread>quot ;
+
+: alien-stack ( params extra -- )
+    over parameters>> length + consume-d >>in-d
+    dup return>> "void" = 0 1 ? produce-d >>out-d
+    drop ;
+
+: return-prep-quot ( node -- quot )
+    return>> [ [ ] ] [ c-type c-type-boxer-quot ] if-void ;
+
+: infer-alien-invoke ( -- )
+    alien-invoke-params new
+    ! Compile-time parameters
+    pop-parameters >>parameters
+    pop-literal nip >>function
+    pop-literal nip >>library
+    pop-literal nip >>return
+    ! Quotation which coerces parameters to required types
+    dup param-prep-quot recursive-state get infer-quot
+    ! Set ABI
+    dup library>> library [ abi>> ] [ "cdecl" ] if* >>abi
+    ! Magic #: consume exactly the number of inputs
+    dup 0 alien-stack
+    ! Add node to IR
+    dup #alien-invoke,
+    ! Quotation which coerces return value to required type
+    return-prep-quot recursive-state get infer-quot ;
+
+: infer-alien-indirect ( -- )
+    alien-indirect-params new
+    ! Compile-time parameters
+    pop-literal nip >>abi
+    pop-parameters >>parameters
+    pop-literal nip >>return
+    ! Quotation which coerces parameters to required types
+    dup param-prep-quot [ dip ] curry recursive-state get infer-quot
+    ! Magic #: consume the function pointer, too
+    dup 1 alien-stack
+    ! Add node to IR
+    dup #alien-indirect,
+    ! Quotation which coerces return value to required type
+    return-prep-quot recursive-state get infer-quot ;
+
+! Callbacks are registered in a global hashtable. If you clear
+! this hashtable, they will all be blown away by code GC, beware
+SYMBOL: callbacks
+
+[ H{ } clone callbacks set-global ] "alien.compiler" add-init-hook
+
+: register-callback ( word -- ) callbacks get conjoin ;
+
+: callback-bottom ( params -- )
+    xt>> [ [ register-callback ] [ word-xt drop <alien> ] bi ] curry
+    recursive-state get infer-quot ;
+
+: infer-alien-callback ( -- )
+    alien-callback-params new
+    pop-literal nip >>quot
+    pop-literal nip >>abi
+    pop-parameters >>parameters
+    pop-literal nip >>return
+    gensym >>xt
+    dup callback-bottom
+    #alien-callback, ;