File: //proc/thread-self/root/proc/thread-self/root/usr/share/guile/2.2/language/cps/compile-bytecode.scm
;;; Continuation-passing style (CPS) intermediate language (IL)
;; Copyright (C) 2013, 2014, 2015 Free Software Foundation, Inc.
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;;
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;;; Lesser General Public License for more details.
;;;;
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;;; Commentary:
;;;
;;; Compiling CPS to bytecode. The result is in the bytecode language,
;;; which happens to be an ELF image as a bytecode.
;;;
;;; Code:
(define-module (language cps compile-bytecode)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (language cps)
#:use-module (language cps primitives)
#:use-module (language cps slot-allocation)
#:use-module (language cps utils)
#:use-module (language cps closure-conversion)
#:use-module (language cps handle-interrupts)
#:use-module (language cps optimize)
#:use-module (language cps reify-primitives)
#:use-module (language cps renumber)
#:use-module (language cps split-rec)
#:use-module (language cps intmap)
#:use-module (language cps intset)
#:use-module (system vm assembler)
#:export (compile-bytecode))
(define (kw-arg-ref args kw default)
(match (memq kw args)
((_ val . _) val)
(_ default)))
(define (intmap-for-each f map)
(intmap-fold (lambda (k v seed) (f k v) seed) map *unspecified*))
(define (intmap-select map set)
(persistent-intmap
(intset-fold
(lambda (k out)
(intmap-add! out k (intmap-ref map k)))
set
empty-intmap)))
;; Any $values expression that continues to a $kargs and causes no
;; shuffles is a forwarding label.
(define (compute-forwarding-labels cps allocation)
(fixpoint
(lambda (forwarding-map)
(intmap-fold (lambda (label target forwarding-map)
(let ((new-target (intmap-ref forwarding-map target
(lambda (target) target))))
(if (eqv? target new-target)
forwarding-map
(intmap-replace forwarding-map label new-target))))
forwarding-map forwarding-map))
(intmap-fold (lambda (label cont forwarding-labels)
(match cont
(($ $kargs _ _ ($ $continue k _ ($ $values)))
(match (lookup-parallel-moves label allocation)
(()
(match (intmap-ref cps k)
(($ $ktail) forwarding-labels)
(_ (intmap-add forwarding-labels label k))))
(_ forwarding-labels)))
(_ forwarding-labels)))
cps empty-intmap)))
(define (compile-function cps asm opts)
(let* ((allocation (allocate-slots cps #:precolor-calls?
(kw-arg-ref opts #:precolor-calls? #t)))
(forwarding-labels (compute-forwarding-labels cps allocation))
(frame-size (lookup-nlocals allocation)))
(define (forward-label k)
(intmap-ref forwarding-labels k (lambda (k) k)))
(define (elide-cont? label)
(match (intmap-ref forwarding-labels label (lambda (_) #f))
(#f #f)
(target (not (eqv? label target)))))
(define (maybe-slot sym)
(lookup-maybe-slot sym allocation))
(define (slot sym)
(lookup-slot sym allocation))
(define (constant sym)
(lookup-constant-value sym allocation))
(define (from-sp var)
(- frame-size 1 var))
(define (maybe-mov dst src)
(unless (= dst src)
(emit-mov asm (from-sp dst) (from-sp src))))
(define (compile-tail label exp)
;; There are only three kinds of expressions in tail position:
;; tail calls, multiple-value returns, and single-value returns.
(match exp
(($ $call proc args)
(for-each (match-lambda
((src . dst) (emit-mov asm (from-sp dst) (from-sp src))))
(lookup-parallel-moves label allocation))
(emit-tail-call asm (1+ (length args))))
(($ $callk k proc args)
(for-each (match-lambda
((src . dst) (emit-mov asm (from-sp dst) (from-sp src))))
(lookup-parallel-moves label allocation))
(emit-tail-call-label asm (1+ (length args)) k))
(($ $values args)
(for-each (match-lambda
((src . dst) (emit-mov asm (from-sp dst) (from-sp src))))
(lookup-parallel-moves label allocation))
(emit-return-values asm (1+ (length args))))))
(define (compile-value label exp dst)
(match exp
(($ $values (arg))
(maybe-mov dst (slot arg)))
(($ $const exp)
(emit-load-constant asm (from-sp dst) exp))
(($ $closure k 0)
(emit-load-static-procedure asm (from-sp dst) k))
(($ $closure k nfree)
(emit-make-closure asm (from-sp dst) k nfree))
(($ $primcall 'current-module)
(emit-current-module asm (from-sp dst)))
(($ $primcall 'current-thread)
(emit-current-thread asm (from-sp dst)))
(($ $primcall 'cached-toplevel-box (scope name bound?))
(emit-cached-toplevel-box asm (from-sp dst)
(constant scope) (constant name)
(constant bound?)))
(($ $primcall 'cached-module-box (mod name public? bound?))
(emit-cached-module-box asm (from-sp dst)
(constant mod) (constant name)
(constant public?) (constant bound?)))
(($ $primcall 'define! (sym))
(emit-define! asm (from-sp dst) (from-sp (slot sym))))
(($ $primcall 'resolve (name bound?))
(emit-resolve asm (from-sp dst) (constant bound?)
(from-sp (slot name))))
(($ $primcall 'free-ref (closure idx))
(emit-free-ref asm (from-sp dst) (from-sp (slot closure))
(constant idx)))
(($ $primcall 'vector-ref (vector index))
(emit-vector-ref asm (from-sp dst) (from-sp (slot vector))
(from-sp (slot index))))
(($ $primcall 'make-vector (length init))
(emit-make-vector asm (from-sp dst) (from-sp (slot length))
(from-sp (slot init))))
(($ $primcall 'make-vector/immediate (length init))
(emit-make-vector/immediate asm (from-sp dst) (constant length)
(from-sp (slot init))))
(($ $primcall 'vector-ref/immediate (vector index))
(emit-vector-ref/immediate asm (from-sp dst) (from-sp (slot vector))
(constant index)))
(($ $primcall 'allocate-struct (vtable nfields))
(emit-allocate-struct asm (from-sp dst) (from-sp (slot vtable))
(from-sp (slot nfields))))
(($ $primcall 'allocate-struct/immediate (vtable nfields))
(emit-allocate-struct/immediate asm (from-sp dst)
(from-sp (slot vtable))
(constant nfields)))
(($ $primcall 'struct-ref (struct n))
(emit-struct-ref asm (from-sp dst) (from-sp (slot struct))
(from-sp (slot n))))
(($ $primcall 'struct-ref/immediate (struct n))
(emit-struct-ref/immediate asm (from-sp dst) (from-sp (slot struct))
(constant n)))
(($ $primcall 'char->integer (src))
(emit-char->integer asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'integer->char (src))
(emit-integer->char asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'add/immediate (x y))
(emit-add/immediate asm (from-sp dst) (from-sp (slot x)) (constant y)))
(($ $primcall 'sub/immediate (x y))
(emit-sub/immediate asm (from-sp dst) (from-sp (slot x)) (constant y)))
(($ $primcall 'uadd/immediate (x y))
(emit-uadd/immediate asm (from-sp dst) (from-sp (slot x))
(constant y)))
(($ $primcall 'usub/immediate (x y))
(emit-usub/immediate asm (from-sp dst) (from-sp (slot x))
(constant y)))
(($ $primcall 'umul/immediate (x y))
(emit-umul/immediate asm (from-sp dst) (from-sp (slot x))
(constant y)))
(($ $primcall 'ursh/immediate (x y))
(emit-ursh/immediate asm (from-sp dst) (from-sp (slot x))
(constant y)))
(($ $primcall 'ulsh/immediate (x y))
(emit-ulsh/immediate asm (from-sp dst) (from-sp (slot x))
(constant y)))
(($ $primcall 'builtin-ref (name))
(emit-builtin-ref asm (from-sp dst) (constant name)))
(($ $primcall 'scm->f64 (src))
(emit-scm->f64 asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'load-f64 (src))
(emit-load-f64 asm (from-sp dst) (constant src)))
(($ $primcall 'f64->scm (src))
(emit-f64->scm asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'scm->u64 (src))
(emit-scm->u64 asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'scm->u64/truncate (src))
(emit-scm->u64/truncate asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'load-u64 (src))
(emit-load-u64 asm (from-sp dst) (constant src)))
(($ $primcall 'u64->scm (src))
(emit-u64->scm asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'scm->s64 (src))
(emit-scm->s64 asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'load-s64 (src))
(emit-load-s64 asm (from-sp dst) (constant src)))
(($ $primcall 's64->scm (src))
(emit-s64->scm asm (from-sp dst) (from-sp (slot src))))
(($ $primcall 'bv-length (bv))
(emit-bv-length asm (from-sp dst) (from-sp (slot bv))))
(($ $primcall 'bv-u8-ref (bv idx))
(emit-bv-u8-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-s8-ref (bv idx))
(emit-bv-s8-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-u16-ref (bv idx))
(emit-bv-u16-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-s16-ref (bv idx))
(emit-bv-s16-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-u32-ref (bv idx val))
(emit-bv-u32-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-s32-ref (bv idx val))
(emit-bv-s32-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-u64-ref (bv idx val))
(emit-bv-u64-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-s64-ref (bv idx val))
(emit-bv-s64-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-f32-ref (bv idx val))
(emit-bv-f32-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'bv-f64-ref (bv idx val))
(emit-bv-f64-ref asm (from-sp dst) (from-sp (slot bv))
(from-sp (slot idx))))
(($ $primcall 'make-atomic-box (init))
(emit-make-atomic-box asm (from-sp dst) (from-sp (slot init))))
(($ $primcall 'atomic-box-ref (box))
(emit-atomic-box-ref asm (from-sp dst) (from-sp (slot box))))
(($ $primcall 'atomic-box-swap! (box val))
(emit-atomic-box-swap! asm (from-sp dst) (from-sp (slot box))
(from-sp (slot val))))
(($ $primcall 'atomic-box-compare-and-swap! (box expected desired))
(emit-atomic-box-compare-and-swap!
asm (from-sp dst) (from-sp (slot box))
(from-sp (slot expected)) (from-sp (slot desired))))
(($ $primcall name args)
;; FIXME: Inline all the cases.
(let ((inst (prim-instruction name)))
(emit-text asm `((,inst ,(from-sp dst)
,@(map (compose from-sp slot) args))))))))
(define (compile-effect label exp k)
(match exp
(($ $values ()) #f)
(($ $prompt escape? tag handler)
(match (intmap-ref cps handler)
(($ $kreceive ($ $arity req () rest () #f) khandler-body)
(let ((receive-args (gensym "handler"))
(nreq (length req))
(proc-slot (lookup-call-proc-slot label allocation)))
(emit-prompt asm (from-sp (slot tag)) escape? proc-slot
receive-args)
(emit-br asm k)
(emit-label asm receive-args)
(unless (and rest (zero? nreq))
(emit-receive-values asm proc-slot (->bool rest) nreq))
(when (and rest
(match (intmap-ref cps khandler-body)
(($ $kargs names (_ ... rest))
(maybe-slot rest))))
(emit-bind-rest asm (+ proc-slot 1 nreq)))
(for-each (match-lambda
((src . dst) (emit-fmov asm dst src)))
(lookup-parallel-moves handler allocation))
(emit-reset-frame asm frame-size)
(emit-br asm (forward-label khandler-body))))))
(($ $primcall 'cache-current-module! (sym scope))
(emit-cache-current-module! asm (from-sp (slot sym)) (constant scope)))
(($ $primcall 'free-set! (closure idx value))
(emit-free-set! asm (from-sp (slot closure)) (from-sp (slot value))
(constant idx)))
(($ $primcall 'box-set! (box value))
(emit-box-set! asm (from-sp (slot box)) (from-sp (slot value))))
(($ $primcall 'struct-set! (struct index value))
(emit-struct-set! asm (from-sp (slot struct)) (from-sp (slot index))
(from-sp (slot value))))
(($ $primcall 'struct-set!/immediate (struct index value))
(emit-struct-set!/immediate asm (from-sp (slot struct))
(constant index) (from-sp (slot value))))
(($ $primcall 'vector-set! (vector index value))
(emit-vector-set! asm (from-sp (slot vector)) (from-sp (slot index))
(from-sp (slot value))))
(($ $primcall 'vector-set!/immediate (vector index value))
(emit-vector-set!/immediate asm (from-sp (slot vector))
(constant index) (from-sp (slot value))))
(($ $primcall 'string-set! (string index char))
(emit-string-set! asm (from-sp (slot string)) (from-sp (slot index))
(from-sp (slot char))))
(($ $primcall 'set-car! (pair value))
(emit-set-car! asm (from-sp (slot pair)) (from-sp (slot value))))
(($ $primcall 'set-cdr! (pair value))
(emit-set-cdr! asm (from-sp (slot pair)) (from-sp (slot value))))
(($ $primcall 'push-fluid (fluid val))
(emit-push-fluid asm (from-sp (slot fluid)) (from-sp (slot val))))
(($ $primcall 'pop-fluid ())
(emit-pop-fluid asm))
(($ $primcall 'push-dynamic-state (state))
(emit-push-dynamic-state asm (from-sp (slot state))))
(($ $primcall 'pop-dynamic-state ())
(emit-pop-dynamic-state asm))
(($ $primcall 'wind (winder unwinder))
(emit-wind asm (from-sp (slot winder)) (from-sp (slot unwinder))))
(($ $primcall 'bv-u8-set! (bv idx val))
(emit-bv-u8-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-s8-set! (bv idx val))
(emit-bv-s8-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-u16-set! (bv idx val))
(emit-bv-u16-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-s16-set! (bv idx val))
(emit-bv-s16-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-u32-set! (bv idx val))
(emit-bv-u32-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-s32-set! (bv idx val))
(emit-bv-s32-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-u64-set! (bv idx val))
(emit-bv-u64-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-s64-set! (bv idx val))
(emit-bv-s64-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-f32-set! (bv idx val))
(emit-bv-f32-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'bv-f64-set! (bv idx val))
(emit-bv-f64-set! asm (from-sp (slot bv)) (from-sp (slot idx))
(from-sp (slot val))))
(($ $primcall 'unwind ())
(emit-unwind asm))
(($ $primcall 'fluid-set! (fluid value))
(emit-fluid-set! asm (from-sp (slot fluid)) (from-sp (slot value))))
(($ $primcall 'atomic-box-set! (box val))
(emit-atomic-box-set! asm (from-sp (slot box)) (from-sp (slot val))))
(($ $primcall 'handle-interrupts ())
(emit-handle-interrupts asm))))
(define (compile-values label exp syms)
(match exp
(($ $values args)
(for-each (match-lambda
((src . dst) (emit-mov asm (from-sp dst) (from-sp src))))
(lookup-parallel-moves label allocation)))))
(define (compile-test label exp kt kf next-label)
(define (prefer-true?)
(if (< (max kt kf) label)
;; Two backwards branches. Prefer
;; the nearest.
(> kt kf)
;; Otherwise prefer a backwards
;; branch or a near jump.
(< kt kf)))
(define (unary op sym)
(cond
((eq? kt next-label)
(op asm (from-sp (slot sym)) #t kf))
((eq? kf next-label)
(op asm (from-sp (slot sym)) #f kt))
(else
(let ((invert? (not (prefer-true?))))
(op asm (from-sp (slot sym)) invert? (if invert? kf kt))
(emit-br asm (if invert? kt kf))))))
(define (binary op a b)
(cond
((eq? kt next-label)
(op asm (from-sp (slot a)) (from-sp (slot b)) #t kf))
((eq? kf next-label)
(op asm (from-sp (slot a)) (from-sp (slot b)) #f kt))
(else
(let ((invert? (not (prefer-true?))))
(op asm (from-sp (slot a)) (from-sp (slot b)) invert?
(if invert? kf kt))
(emit-br asm (if invert? kt kf))))))
(match exp
(($ $values (sym)) (unary emit-br-if-true sym))
(($ $primcall 'null? (a)) (unary emit-br-if-null a))
(($ $primcall 'nil? (a)) (unary emit-br-if-nil a))
(($ $primcall 'pair? (a)) (unary emit-br-if-pair a))
(($ $primcall 'struct? (a)) (unary emit-br-if-struct a))
(($ $primcall 'char? (a)) (unary emit-br-if-char a))
(($ $primcall 'symbol? (a)) (unary emit-br-if-symbol a))
(($ $primcall 'variable? (a)) (unary emit-br-if-variable a))
(($ $primcall 'vector? (a)) (unary emit-br-if-vector a))
(($ $primcall 'string? (a)) (unary emit-br-if-string a))
(($ $primcall 'bytevector? (a)) (unary emit-br-if-bytevector a))
(($ $primcall 'bitvector? (a)) (unary emit-br-if-bitvector a))
(($ $primcall 'keyword? (a)) (unary emit-br-if-keyword a))
;; Add more TC7 tests here. Keep in sync with
;; *branching-primcall-arities* in (language cps primitives) and
;; the set of macro-instructions in assembly.scm.
(($ $primcall 'eq? (a b)) (binary emit-br-if-eq a b))
(($ $primcall 'eqv? (a b)) (binary emit-br-if-eqv a b))
(($ $primcall '< (a b)) (binary emit-br-if-< a b))
(($ $primcall '<= (a b)) (binary emit-br-if-<= a b))
(($ $primcall '= (a b)) (binary emit-br-if-= a b))
(($ $primcall '>= (a b)) (binary emit-br-if-<= b a))
(($ $primcall '> (a b)) (binary emit-br-if-< b a))
(($ $primcall 'u64-< (a b)) (binary emit-br-if-u64-< a b))
(($ $primcall 'u64-<= (a b)) (binary emit-br-if-u64-<= a b))
(($ $primcall 'u64-= (a b)) (binary emit-br-if-u64-= a b))
(($ $primcall 'u64->= (a b)) (binary emit-br-if-u64-<= b a))
(($ $primcall 'u64-> (a b)) (binary emit-br-if-u64-< b a))
(($ $primcall 'u64-<-scm (a b)) (binary emit-br-if-u64-<-scm a b))
(($ $primcall 'u64-<=-scm (a b)) (binary emit-br-if-u64-<=-scm a b))
(($ $primcall 'u64-=-scm (a b)) (binary emit-br-if-u64-=-scm a b))
(($ $primcall 'u64->=-scm (a b)) (binary emit-br-if-u64->=-scm a b))
(($ $primcall 'u64->-scm (a b)) (binary emit-br-if-u64->-scm a b))
(($ $primcall 'logtest (a b)) (binary emit-br-if-logtest a b))
(($ $primcall 'f64-< (a b)) (binary emit-br-if-f64-< a b))
(($ $primcall 'f64-<= (a b)) (binary emit-br-if-f64-<= a b))
(($ $primcall 'f64-= (a b)) (binary emit-br-if-f64-= a b))
(($ $primcall 'f64->= (a b)) (binary emit-br-if-f64->= a b))
(($ $primcall 'f64-> (a b)) (binary emit-br-if-f64-> a b))))
(define (compile-trunc label k exp nreq rest-var)
(define (do-call proc args emit-call)
(let* ((proc-slot (lookup-call-proc-slot label allocation))
(nargs (1+ (length args)))
(arg-slots (map (lambda (x) (+ x proc-slot)) (iota nargs))))
(for-each (match-lambda
((src . dst) (emit-mov asm (from-sp dst) (from-sp src))))
(lookup-parallel-moves label allocation))
(emit-call asm proc-slot nargs)
(emit-slot-map asm proc-slot (lookup-slot-map label allocation))
(cond
((and (= 1 nreq) (and rest-var) (not (maybe-slot rest-var))
(match (lookup-parallel-moves k allocation)
((((? (lambda (src) (= src (1+ proc-slot))) src)
. dst)) dst)
(_ #f)))
;; The usual case: one required live return value, ignoring
;; any additional values.
=> (lambda (dst)
(emit-receive asm dst proc-slot frame-size)))
(else
(unless (and (zero? nreq) rest-var)
(emit-receive-values asm proc-slot (->bool rest-var) nreq))
(when (and rest-var (maybe-slot rest-var))
(emit-bind-rest asm (+ proc-slot 1 nreq)))
(for-each (match-lambda
((src . dst) (emit-fmov asm dst src)))
(lookup-parallel-moves k allocation))
(emit-reset-frame asm frame-size)))))
(match exp
(($ $call proc args)
(do-call proc args
(lambda (asm proc-slot nargs)
(emit-call asm proc-slot nargs))))
(($ $callk k proc args)
(do-call proc args
(lambda (asm proc-slot nargs)
(emit-call-label asm proc-slot nargs k))))))
(define (skip-elided-conts label)
(if (elide-cont? label)
(skip-elided-conts (1+ label))
label))
(define (compile-expression label k exp)
(let* ((forwarded-k (forward-label k))
(fallthrough? (= forwarded-k (skip-elided-conts (1+ label)))))
(define (maybe-emit-jump)
(unless fallthrough?
(emit-br asm forwarded-k)))
(match (intmap-ref cps k)
(($ $ktail)
(compile-tail label exp))
(($ $kargs (name) (sym))
(let ((dst (maybe-slot sym)))
(when dst
(compile-value label exp dst)))
(maybe-emit-jump))
(($ $kargs () ())
(match exp
(($ $branch kt exp)
(compile-test label exp (forward-label kt) forwarded-k
(skip-elided-conts (1+ label))))
(_
(compile-effect label exp k)
(maybe-emit-jump))))
(($ $kargs names syms)
(compile-values label exp syms)
(maybe-emit-jump))
(($ $kreceive ($ $arity req () rest () #f) kargs)
(compile-trunc label k exp (length req)
(and rest
(match (intmap-ref cps kargs)
(($ $kargs names (_ ... rest)) rest))))
(let* ((kargs (forward-label kargs))
(fallthrough? (and fallthrough?
(= kargs (skip-elided-conts (1+ k))))))
(unless fallthrough?
(emit-br asm kargs)))))))
(define (compile-cont label cont)
(match cont
(($ $kfun src meta self tail clause)
(when src
(emit-source asm src))
(emit-begin-program asm label meta))
(($ $kclause ($ $arity req opt rest kw allow-other-keys?) body alt)
(let ((first? (match (intmap-ref cps (1- label))
(($ $kfun) #t)
(_ #f)))
(kw-indices (map (match-lambda
((key name sym)
(cons key (lookup-slot sym allocation))))
kw)))
(unless first?
(emit-end-arity asm))
(emit-label asm label)
(emit-begin-kw-arity asm req opt rest kw-indices allow-other-keys?
frame-size alt)
;; All arities define a closure binding in slot 0.
(emit-definition asm 'closure 0 'scm)
;; Usually we just fall through, but it could be the body is
;; contified into another clause.
(let ((body (forward-label body)))
(unless (= body (skip-elided-conts (1+ label)))
(emit-br asm body)))))
(($ $kargs names vars ($ $continue k src exp))
(emit-label asm label)
(for-each (lambda (name var)
(let ((slot (maybe-slot var)))
(when slot
(let ((repr (lookup-representation var allocation)))
(emit-definition asm name slot repr)))))
names vars)
(when src
(emit-source asm src))
(unless (elide-cont? label)
(compile-expression label k exp)))
(($ $kreceive arity kargs)
(emit-label asm label))
(($ $ktail)
(emit-end-arity asm)
(emit-end-program asm))))
(intmap-for-each compile-cont cps)))
(define (emit-bytecode exp env opts)
(let ((asm (make-assembler)))
(intmap-for-each (lambda (kfun body)
(compile-function (intmap-select exp body) asm opts))
(compute-reachable-functions exp 0))
(values (link-assembly asm #:page-aligned? (kw-arg-ref opts #:to-file? #f))
env
env)))
(define (lower-cps exp opts)
;; FIXME: For now the closure conversion pass relies on $rec instances
;; being separated into SCCs. We should fix this to not be the case,
;; and instead move the split-rec pass back to
;; optimize-higher-order-cps.
(set! exp (split-rec exp))
(set! exp (optimize-higher-order-cps exp opts))
(set! exp (convert-closures exp))
(set! exp (optimize-first-order-cps exp opts))
(set! exp (reify-primitives exp))
(set! exp (add-handle-interrupts exp))
(renumber exp))
(define (compile-bytecode exp env opts)
(set! exp (lower-cps exp opts))
(emit-bytecode exp env opts))