[bpt/guile.git] / module / language / cps / compile-bytecode.scm

;;; Continuation-passing style (CPS) intermediate language (IL)

;; Copyright (C) 2013, 2014 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 arities)
  #:use-module (language cps closure-conversion)
  #:use-module (language cps contification)
  #:use-module (language cps constructors)
  #:use-module (language cps dfg)
  #:use-module (language cps elide-values)
  #:use-module (language cps primitives)
  #:use-module (language cps reify-primitives)
  #:use-module (language cps slot-allocation)
  #:use-module (language cps specialize-primcalls)
  #:use-module (system vm assembler)
  #:export (compile-bytecode))

;; TODO: Local var names.

(define (kw-arg-ref args kw default)
  (match (memq kw args)
    ((_ val . _) val)
    (_ default)))

(define (optimize exp opts)
  (define (run-pass exp pass kw default)
    (if (kw-arg-ref opts kw default)
        (pass exp)
        exp))

  ;; Calls to source-to-source optimization passes go here.
  (let* ((exp (run-pass exp contify #:contify? #t))
         (exp (run-pass exp inline-constructors #:inline-constructors? #t))
         (exp (run-pass exp specialize-primcalls #:specialize-primcalls? #t))
         (exp (run-pass exp elide-values #:elide-values? #t)))
    ;; Passes that are needed:
    ;; 
    ;;  * Abort contification: turning abort primcalls into continuation
    ;;    calls, and eliding prompts if possible.
    ;;
    ;;  * Common subexpression elimination.  Desperately needed.  Requires
    ;;    effects analysis.
    ;;
    ;;  * Loop peeling.  Unrolls the first round through a loop if the
    ;;    loop has effects that CSE can work on.  Requires effects
    ;;    analysis.  When run before CSE, loop peeling is the equivalent
    ;;    of loop-invariant code motion (LICM).
    ;;
    ;;  * Generic simplification pass, to be run as needed.  Used to
    ;;    "clean up", both on the original raw input and after specific
    ;;    optimization passes.

    exp))

(define (collect-conts f cfa)
  (let ((contv (make-vector (cfa-k-count cfa) #f)))
    (fold-local-conts
     (lambda (k cont tail)
       (let ((idx (cfa-k-idx cfa k #:default (lambda (k) #f))))
         (when idx
           (vector-set! contv idx cont))))
     '()
     (match f
       (($ $fun src meta free entry)
        entry)))
    contv))

(define (compile-fun f asm)
  (let* ((dfg (compute-dfg f #:global? #f))
         (cfa (analyze-control-flow f dfg))
         (allocation (allocate-slots f dfg))
         (contv (collect-conts f cfa)))
    (define (lookup-cont k)
      (vector-ref contv (cfa-k-idx cfa k)))

    (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 (maybe-mov dst src)
      (unless (= dst src)
        (emit-mov asm dst src)))

    (define (maybe-load-constant slot src)
      (call-with-values (lambda ()
                          (lookup-maybe-constant-value src allocation))
        (lambda (has-const? val)
          (and has-const?
               (begin
                 (emit-load-constant asm slot val)
                 #t)))))

    (define (compile-entry meta)
      (match (vector-ref contv 0)
        (($ $kentry self tail clauses)
         (emit-begin-program asm (cfa-k-sym cfa 0) meta)
         (let lp ((n 1)
                  (ks (map (match-lambda (($ $cont k) k)) clauses)))
           (match ks
             (()
              (unless (= n (vector-length contv))
                (error "unexpected end of clauses"))
              (emit-end-program asm))
             ((k . ks)
              (unless (eq? (cfa-k-sym cfa n) k)
                (error "unexpected k" k))
              (lp (compile-clause n (and (pair? ks) (car ks)))
                  ks)))))))

    (define (compile-clause n alternate)
      (match (vector-ref contv n)
        (($ $kclause ($ $arity req opt rest kw allow-other-keys?))
         (let* ((kw-indices (map (match-lambda
                                  ((key name sym)
                                   (cons key (lookup-slot sym allocation))))
                                 kw))
                (k (cfa-k-sym cfa n))
                (nlocals (lookup-nlocals k allocation)))
           (emit-label asm k)
           (emit-begin-kw-arity asm req opt rest kw-indices
                                allow-other-keys? nlocals alternate)
           (let ((next (compile-body (1+ n) nlocals)))
             (emit-end-arity asm)
             next)))))

    (define (compile-body n nlocals)
      (let compile-cont ((n n))
        (if (= n (vector-length contv))
            n
            (match (vector-ref contv n)
              (($ $kclause) n)
              (($ $kargs _ _ term)
               (emit-label asm (cfa-k-sym cfa n))
               (let find-exp ((term term))
                 (match term
                   (($ $letk conts term)
                    (find-exp term))
                   (($ $continue k src exp)
                    (when src
                      (emit-source asm src))
                    (compile-expression n k exp nlocals)
                    (compile-cont (1+ n))))))
              (_
               (emit-label asm (cfa-k-sym cfa n))
               (compile-cont (1+ n)))))))

    (define (compile-expression n k exp nlocals)
      (let* ((label (cfa-k-sym cfa n))
             (k-idx (cfa-k-idx cfa k))
             (fallthrough? (= k-idx (1+ n))))
        (define (maybe-emit-jump)
          (unless (= k-idx (1+ n))
            (emit-br asm k)))
        (match (vector-ref contv k-idx)
          (($ $ktail)
           (compile-tail label exp))
          (($ $kargs (name) (sym))
           (let ((dst (maybe-slot sym)))
             (when dst
               (compile-value label exp dst nlocals)))
           (maybe-emit-jump))
          (($ $kargs () ())
           (compile-effect label exp k nlocals)
           (maybe-emit-jump))
          (($ $kargs names syms)
           (compile-values label exp syms)
           (maybe-emit-jump))
          (($ $kif kt kf)
           (compile-test label exp kt kf
                         (and (= k-idx (1+ n))
                              (< (+ n 2) (cfa-k-count cfa))
                              (cfa-k-sym cfa (+ n 2)))))
          (($ $ktrunc ($ $arity req () rest () #f) kargs)
           (compile-trunc label k exp (length req)
                          (and rest
                               (match (vector-ref contv (cfa-k-idx cfa kargs))
                                 (($ $kargs names (_ ... rest)) rest)))
                          nlocals)
           (unless (and (= k-idx (1+ n))
                        (< (+ n 2) (cfa-k-count cfa))
                        (eq? (cfa-k-sym cfa (+ n 2)) kargs))
             (emit-br asm kargs))))))

    (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
        (($ $call proc args)
         (for-each (match-lambda
                    ((src . dst) (emit-mov asm dst src)))
                   (lookup-parallel-moves label allocation))
         (let ((tail-slots (cdr (iota (1+ (length args))))))
           (for-each maybe-load-constant tail-slots args))
         (emit-tail-call asm (1+ (length args))))
        (($ $values ())
         (emit-reset-frame asm 1)
         (emit-return-values asm))
        (($ $values (arg))
         (if (maybe-slot arg)
             (emit-return asm (slot arg))
             (begin
               (emit-load-constant asm 1 (constant arg))
               (emit-return asm 1))))
        (($ $values args)
         (for-each (match-lambda
                    ((src . dst) (emit-mov asm dst src)))
                   (lookup-parallel-moves label allocation))
         (let ((tail-slots (cdr (iota (1+ (length args))))))
           (for-each maybe-load-constant tail-slots args))
         (emit-reset-frame asm (1+ (length args)))
         (emit-return-values asm))
        (($ $primcall 'return (arg))
         (emit-return asm (slot arg)))))

    (define (compile-value label exp dst nlocals)
      (match exp
        (($ $values (arg))
         (or (maybe-load-constant dst arg)
             (maybe-mov dst (slot arg))))
        (($ $void)
         (emit-load-constant asm dst *unspecified*))
        (($ $const exp)
         (emit-load-constant asm dst exp))
        (($ $fun src meta () ($ $cont k))
         (emit-load-static-procedure asm dst k))
        (($ $fun src meta free ($ $cont k))
         (emit-make-closure asm dst k (length free)))
        (($ $call proc args)
         (let* ((proc-slot (lookup-call-proc-slot label allocation))
                (nargs (1+ (length args)))
                (arg-slots (map (lambda (x) (+ x proc-slot)) (iota nargs))))
           (for-each (match-lambda
                      ((src . dst) (emit-mov asm dst src)))
                     (lookup-parallel-moves label allocation))
           (for-each maybe-load-constant arg-slots (cons proc args))
           (emit-call asm proc-slot nargs)
           (cond
            (dst
             (emit-receive asm dst proc-slot nlocals))
            (else
             ;; FIXME: Only allow more values if there is a rest arg.
             ;; Express values truncation by the presence of an
             ;; unused rest arg instead of implicitly.
             (emit-receive-values asm proc-slot #t 1)
             (emit-reset-frame asm nlocals)))))
        (($ $primcall 'current-module)
         (emit-current-module asm dst))
        (($ $primcall 'cached-toplevel-box (scope name bound?))
         (emit-cached-toplevel-box asm dst (constant scope) (constant name)
                                   (constant bound?)))
        (($ $primcall 'cached-module-box (mod name public? bound?))
         (emit-cached-module-box asm dst (constant mod) (constant name)
                                 (constant public?) (constant bound?)))
        (($ $primcall 'resolve (name bound?))
         (emit-resolve asm dst (constant bound?) (slot name)))
        (($ $primcall 'free-ref (closure idx))
         (emit-free-ref asm dst (slot closure) (constant idx)))
        (($ $primcall 'vector-ref (vector index))
         (emit-vector-ref asm dst (slot vector) (slot index)))
        (($ $primcall 'make-vector/immediate (length init))
         (emit-make-vector/immediate asm dst (constant length) (slot init)))
        (($ $primcall 'vector-ref/immediate (vector index))
         (emit-vector-ref/immediate asm dst (slot vector) (constant index)))
        (($ $primcall 'allocate-struct/immediate (vtable nfields))
         (emit-allocate-struct/immediate asm dst (slot vtable) (constant nfields)))
        (($ $primcall 'struct-ref/immediate (struct n))
         (emit-struct-ref/immediate asm dst (slot struct) (constant n)))
        (($ $primcall 'builtin-ref (name))
         (emit-builtin-ref asm dst (constant name)))
        (($ $primcall 'bv-u8-ref (bv idx))
         (emit-bv-u8-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-s8-ref (bv idx))
         (emit-bv-s8-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-u16-ref (bv idx))
         (emit-bv-u16-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-s16-ref (bv idx))
         (emit-bv-s16-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-u32-ref (bv idx val))
         (emit-bv-u32-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-s32-ref (bv idx val))
         (emit-bv-s32-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-u64-ref (bv idx val))
         (emit-bv-u64-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-s64-ref (bv idx val))
         (emit-bv-s64-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-f32-ref (bv idx val))
         (emit-bv-f32-ref asm dst (slot bv) (slot idx)))
        (($ $primcall 'bv-f64-ref (bv idx val))
         (emit-bv-f64-ref asm dst (slot bv) (slot idx)))
        (($ $primcall name args)
         ;; FIXME: Inline all the cases.
         (let ((inst (prim-instruction name)))
           (emit-text asm `((,inst ,dst ,@(map slot args))))))))

    (define (compile-effect label exp k nlocals)
      (match exp
        (($ $values ()) #f)
        (($ $prompt escape? tag handler)
         (match (lookup-cont handler)
           (($ $ktrunc ($ $arity req () rest () #f) khandler-body)
            (let ((receive-args (gensym "handler"))
                  (nreq (length req))
                  (proc-slot (lookup-call-proc-slot handler allocation)))
              (emit-prompt asm (slot tag) escape? proc-slot receive-args)
              (emit-br asm k)
              (emit-label asm receive-args)
              (emit-receive-values asm proc-slot (->bool rest) nreq)
              (when (and rest
                         (match (vector-ref contv (cfa-k-idx cfa khandler-body))
                           (($ $kargs names (_ ... rest))
                            (maybe-slot rest))))
                (emit-bind-rest asm (+ proc-slot 1 nreq)))
              (for-each (match-lambda
                         ((src . dst) (emit-mov asm dst src)))
                        (lookup-parallel-moves handler allocation))
              (emit-reset-frame asm nlocals)
              (emit-br asm khandler-body)))))
        (($ $primcall 'cache-current-module! (sym scope))
         (emit-cache-current-module! asm (slot sym) (constant scope)))
        (($ $primcall 'free-set! (closure idx value))
         (emit-free-set! asm (slot closure) (slot value) (constant idx)))
        (($ $primcall 'box-set! (box value))
         (emit-box-set! asm (slot box) (slot value)))
        (($ $primcall 'struct-set!/immediate (struct index value))
         (emit-struct-set!/immediate asm (slot struct) (constant index) (slot value)))
        (($ $primcall 'vector-set! (vector index value))
         (emit-vector-set! asm (slot vector) (slot index) (slot value)))
        (($ $primcall 'vector-set!/immediate (vector index value))
         (emit-vector-set!/immediate asm (slot vector) (constant index)
                                     (slot value)))
        (($ $primcall 'variable-set! (var val))
         (emit-box-set! asm (slot var) (slot val)))
        (($ $primcall 'set-car! (pair value))
         (emit-set-car! asm (slot pair) (slot value)))
        (($ $primcall 'set-cdr! (pair value))
         (emit-set-cdr! asm (slot pair) (slot value)))
        (($ $primcall 'define! (sym value))
         (emit-define! asm (slot sym) (slot value)))
        (($ $primcall 'push-fluid (fluid val))
         (emit-push-fluid asm (slot fluid) (slot val)))
        (($ $primcall 'pop-fluid ())
         (emit-pop-fluid asm))
        (($ $primcall 'wind (winder unwinder))
         (emit-wind asm (slot winder) (slot unwinder)))
        (($ $primcall 'bv-u8-set! (bv idx val))
         (emit-bv-u8-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-s8-set! (bv idx val))
         (emit-bv-s8-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-u16-set! (bv idx val))
         (emit-bv-u16-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-s16-set! (bv idx val))
         (emit-bv-s16-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-u32-set! (bv idx val))
         (emit-bv-u32-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-s32-set! (bv idx val))
         (emit-bv-s32-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-u64-set! (bv idx val))
         (emit-bv-u64-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-s64-set! (bv idx val))
         (emit-bv-s64-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-f32-set! (bv idx val))
         (emit-bv-f32-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'bv-f64-set! (bv idx val))
         (emit-bv-f64-set! asm (slot bv) (slot idx) (slot val)))
        (($ $primcall 'unwind ())
         (emit-unwind asm))))

    (define (compile-values label exp syms)
      (match exp
        (($ $values args)
         (for-each (match-lambda
                    ((src . dst) (emit-mov asm dst src)))
                   (lookup-parallel-moves label allocation))
         (for-each maybe-load-constant (map slot syms) args))))

    (define (compile-test label exp kt kf next-label)
      (define (unary op sym)
        (cond
         ((eq? kt next-label)
          (op asm (slot sym) #t kf))
         (else
          (op asm (slot sym) #f kt)
          (unless (eq? kf next-label)
            (emit-br asm kf)))))
      (define (binary op a b)
        (cond
         ((eq? kt next-label)
          (op asm (slot a) (slot b) #t kf))
         (else
          (op asm (slot a) (slot b) #f kt)
          (unless (eq? kf next-label)
            (emit-br asm kf)))))
      (match exp
        (($ $values (sym))
         (call-with-values (lambda ()
                             (lookup-maybe-constant-value sym allocation))
           (lambda (has-const? val)
             (if has-const?
                 (if val
                     (unless (eq? kt next-label)
                       (emit-br asm kt))
                     (unless (eq? kf next-label)
                       (emit-br asm kf)))
                 (unary emit-br-if-true sym)))))
        (($ $primcall 'null? (a)) (unary emit-br-if-null a))
        (($ $primcall 'nil? (a)) (unary emit-br-if-nil a))
        (($ $primcall 'pair? (a)) (unary emit-br-if-pair a))
        (($ $primcall 'struct? (a)) (unary emit-br-if-struct a))
        (($ $primcall 'char? (a)) (unary emit-br-if-char a))
        (($ $primcall 'symbol? (a)) (unary emit-br-if-symbol a))
        (($ $primcall 'variable? (a)) (unary emit-br-if-variable a))
        (($ $primcall 'vector? (a)) (unary emit-br-if-vector a))
        (($ $primcall 'string? (a)) (unary emit-br-if-string a))
        (($ $primcall 'bytevector? (a)) (unary emit-br-if-bytevector a))
        ;; Add more TC7 tests here.  Keep in sync with
        ;; *branching-primcall-arities* in (language cps primitives) and
        ;; the set of macro-instructions in assembly.scm.
        (($ $primcall 'eq? (a b)) (binary emit-br-if-eq a b))
        (($ $primcall 'eqv? (a b)) (binary emit-br-if-eqv a b))
        (($ $primcall 'equal? (a b)) (binary emit-br-if-equal a b))
        (($ $primcall '< (a b)) (binary emit-br-if-< a b))
        (($ $primcall '<= (a b)) (binary emit-br-if-<= a b))
        (($ $primcall '= (a b)) (binary emit-br-if-= a b))
        (($ $primcall '>= (a b)) (binary emit-br-if-<= b a))
        (($ $primcall '> (a b)) (binary emit-br-if-< b a))))

    (define (compile-trunc label k exp nreq rest-var nlocals)
      (match exp
        (($ $call proc args)
         (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 dst src)))
                     (lookup-parallel-moves label allocation))
           (for-each maybe-load-constant arg-slots (cons proc args))
           (emit-call asm proc-slot nargs)
           ;; FIXME: Only allow more values if there is a rest arg.
           ;; Express values truncation by the presence of an
           ;; unused rest arg instead of implicitly.
           (emit-receive-values asm proc-slot #t nreq)
           (when (and rest-var (maybe-slot rest-var))
             (emit-bind-rest asm (+ proc-slot 1 nreq)))
           (for-each (match-lambda
                      ((src . dst) (emit-mov asm dst src)))
                     (lookup-parallel-moves k allocation))
           (emit-reset-frame asm nlocals)))))

    (match f
      (($ $fun src meta free ($ $cont k ($ $kentry self tail clauses)))
       ;; FIXME: src on kentry instead?
       (when src
         (emit-source asm src))
       (compile-entry (or meta '()))))))

(define (visit-funs proc exp)
  (match exp
    (($ $continue _ _ exp)
     (visit-funs proc exp))

    (($ $fun src meta free body)
     (proc exp)
     (visit-funs proc body))

    (($ $letk conts body)
     (visit-funs proc body)
     (for-each (lambda (cont) (visit-funs proc cont)) conts))

    (($ $cont sym ($ $kargs names syms body))
     (visit-funs proc body))

    (($ $cont sym ($ $kclause arity body))
     (visit-funs proc body))

    (($ $cont sym ($ $kentry self tail clauses))
     (for-each (lambda (clause) (visit-funs proc clause)) clauses))

    (_ (values))))

(define (compile-bytecode exp env opts)
  (let* ((exp (fix-arities exp))
         (exp (optimize exp opts))
         (exp (convert-closures exp))
         (exp (reify-primitives exp))
         (asm (make-assembler)))
    (visit-funs (lambda (fun)
                  (compile-fun fun asm))
                exp)
    (values (link-assembly asm #:page-aligned? (kw-arg-ref opts #:to-file? #f))
            env
            env)))
Commit	Line	Data
6e8ad823 AW	1	;;; Continuation-passing style (CPS) intermediate language (IL)
6e8ad823 AW	2
7ab76a83	3	;; Copyright (C) 2013, 2014 Free Software Foundation, Inc.
6e8ad823 AW	4
	5	;;;; This library is free software; you can redistribute it and/or
	6	;;;; modify it under the terms of the GNU Lesser General Public
	7	;;;; License as published by the Free Software Foundation; either
	8	;;;; version 3 of the License, or (at your option) any later version.
	9	;;;;
	10	;;;; This library is distributed in the hope that it will be useful,
	11	;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	;;;; Lesser General Public License for more details.
	14	;;;;
	15	;;;; You should have received a copy of the GNU Lesser General Public
	16	;;;; License along with this library; if not, write to the Free Software
	17	;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	18
	19	;;; Commentary:
	20	;;;
691697de AW	21	;;; Compiling CPS to bytecode. The result is in the bytecode language,
691697de AW	22	;;; which happens to be an ELF image as a bytecode.
6e8ad823 AW	23	;;;
	24	;;; Code:
	25
691697de	26	(define-module (language cps compile-bytecode)
6e8ad823 AW	27	#:use-module (ice-9 match)
	28	#:use-module (srfi srfi-1)
	29	#:use-module (language cps)
	30	#:use-module (language cps arities)
	31	#:use-module (language cps closure-conversion)
8ac8e2df	32	#:use-module (language cps contification)
fa3b6e57	33	#:use-module (language cps constructors)
6e8ad823	34	#:use-module (language cps dfg)
7e273b7a	35	#:use-module (language cps elide-values)
6e8ad823 AW	36	#:use-module (language cps primitives)
	37	#:use-module (language cps reify-primitives)
	38	#:use-module (language cps slot-allocation)
4c906ad5	39	#:use-module (language cps specialize-primcalls)
6e8ad823	40	#:use-module (system vm assembler)
691697de	41	#:export (compile-bytecode))
6e8ad823	42
d258fccc	43	;; TODO: Local var names.
6e8ad823 AW	44
	45	(define (kw-arg-ref args kw default)
	46	(match (memq kw args)
	47	((_ val . _) val)
	48	(_ default)))
	49
	50	(define (optimize exp opts)
	51	(define (run-pass exp pass kw default)
	52	(if (kw-arg-ref opts kw default)
1d15832f	53	(pass exp)
6e8ad823 AW	54	exp))
	55
	56	;; Calls to source-to-source optimization passes go here.
fa3b6e57	57	(let* ((exp (run-pass exp contify #:contify? #t))
7e273b7a	58	(exp (run-pass exp inline-constructors #:inline-constructors? #t))
4c906ad5	59	(exp (run-pass exp specialize-primcalls #:specialize-primcalls? #t))
7e273b7a	60	(exp (run-pass exp elide-values #:elide-values? #t)))
6e8ad823 AW	61	;; Passes that are needed:
6e8ad823 AW	62	;;
6e8ad823 AW	63	;; * Abort contification: turning abort primcalls into continuation
	64	;; calls, and eliding prompts if possible.
	65	;;
	66	;; * Common subexpression elimination. Desperately needed. Requires
	67	;; effects analysis.
	68	;;
	69	;; * Loop peeling. Unrolls the first round through a loop if the
	70	;; loop has effects that CSE can work on. Requires effects
	71	;; analysis. When run before CSE, loop peeling is the equivalent
	72	;; of loop-invariant code motion (LICM).
	73	;;
	74	;; * Generic simplification pass, to be run as needed. Used to
	75	;; "clean up", both on the original raw input and after specific
	76	;; optimization passes.
	77
	78	exp))
	79
d258fccc	80	(define (collect-conts f cfa)
6e422a35	81	(let ((contv (make-vector (cfa-k-count cfa) #f)))
d258fccc	82	(fold-local-conts
6e422a35	83	(lambda (k cont tail)
d258fccc AW	84	(let ((idx (cfa-k-idx cfa k #:default (lambda (k) #f))))
d258fccc AW	85	(when idx
d258fccc AW	86	(vector-set! contv idx cont))))
	87	'()
	88	(match f
6e422a35	89	(($ $fun src meta free entry)
d258fccc	90	entry)))
6e422a35	91	contv))
d258fccc AW	92
	93	(define (compile-fun f asm)
	94	(let* ((dfg (compute-dfg f #:global? #f))
	95	(cfa (analyze-control-flow f dfg))
6e422a35 AW	96	(allocation (allocate-slots f dfg))
	97	(contv (collect-conts f cfa)))
	98	(define (lookup-cont k)
	99	(vector-ref contv (cfa-k-idx cfa k)))
	100
987c1f5f AW	101	(define (maybe-slot sym)
	102	(lookup-maybe-slot sym allocation))
	103
6e422a35 AW	104	(define (slot sym)
	105	(lookup-slot sym allocation))
	106
	107	(define (constant sym)
	108	(lookup-constant-value sym allocation))
	109
	110	(define (maybe-mov dst src)
	111	(unless (= dst src)
	112	(emit-mov asm dst src)))
	113
	114	(define (maybe-load-constant slot src)
	115	(call-with-values (lambda ()
	116	(lookup-maybe-constant-value src allocation))
	117	(lambda (has-const? val)
	118	(and has-const?
	119	(begin
	120	(emit-load-constant asm slot val)
	121	#t)))))
	122
	123	(define (compile-entry meta)
	124	(match (vector-ref contv 0)
	125	(($ $kentry self tail clauses)
	126	(emit-begin-program asm (cfa-k-sym cfa 0) meta)
	127	(let lp ((n 1)
	128	(ks (map (match-lambda (($ $cont k) k)) clauses)))
	129	(match ks
	130	(()
	131	(unless (= n (vector-length contv))
	132	(error "unexpected end of clauses"))
	133	(emit-end-program asm))
	134	((k . ks)
	135	(unless (eq? (cfa-k-sym cfa n) k)
	136	(error "unexpected k" k))
	137	(lp (compile-clause n (and (pair? ks) (car ks)))
	138	ks)))))))
	139
	140	(define (compile-clause n alternate)
	141	(match (vector-ref contv n)
	142	(($ $kclause ($ $arity req opt rest kw allow-other-keys?))
	143	(let* ((kw-indices (map (match-lambda
	144	((key name sym)
	145	(cons key (lookup-slot sym allocation))))
	146	kw))
	147	(k (cfa-k-sym cfa n))
	148	(nlocals (lookup-nlocals k allocation)))
	149	(emit-label asm k)
	150	(emit-begin-kw-arity asm req opt rest kw-indices
	151	allow-other-keys? nlocals alternate)
	152	(let ((next (compile-body (1+ n) nlocals)))
	153	(emit-end-arity asm)
	154	next)))))
	155
	156	(define (compile-body n nlocals)
	157	(let compile-cont ((n n))
	158	(if (= n (vector-length contv))
	159	n
	160	(match (vector-ref contv n)
	161	(($ $kclause) n)
	162	(($ $kargs _ _ term)
	163	(emit-label asm (cfa-k-sym cfa n))
	164	(let find-exp ((term term))
	165	(match term
	166	(($ $letk conts term)
	167	(find-exp term))
168	(($ $continue k src exp)
169	(when src
170	(emit-source asm src))
171	(compile-expression n k exp nlocals)
172	(compile-cont (1+ n))))))
173	(_
174	(emit-label asm (cfa-k-sym cfa n))
175	(compile-cont (1+ n)))))))
176
177	(define (compile-expression n k exp nlocals)
178	(let* ((label (cfa-k-sym cfa n))
179	(k-idx (cfa-k-idx cfa k))
180	(fallthrough? (= k-idx (1+ n))))
181	(define (maybe-emit-jump)
182	(unless (= k-idx (1+ n))
183	(emit-br asm k)))
184	(match (vector-ref contv k-idx)
185	(($ $ktail)
186	(compile-tail label exp))
187	(($ $kargs (name) (sym))
987c1f5f	188	(let ((dst (maybe-slot sym)))
6e422a35 AW	189	(when dst
	190	(compile-value label exp dst nlocals)))
	191	(maybe-emit-jump))
	192	(($ $kargs () ())
	193	(compile-effect label exp k nlocals)
	194	(maybe-emit-jump))
	195	(($ $kargs names syms)
	196	(compile-values label exp syms)
	197	(maybe-emit-jump))
	198	(($ $kif kt kf)
	199	(compile-test label exp kt kf
	200	(and (= k-idx (1+ n))
	201	(< (+ n 2) (cfa-k-count cfa))
	202	(cfa-k-sym cfa (+ n 2)))))
987c1f5f	203	(($ $ktrunc ($ $arity req () rest () #f) kargs)
fa48a2f7 AW	204	(compile-trunc label k exp (length req)
	205	(and rest
	206	(match (vector-ref contv (cfa-k-idx cfa kargs))
	207	(($ $kargs names (_ ... rest)) rest)))
	208	nlocals)
6e422a35 AW	209	(unless (and (= k-idx (1+ n))
6e422a35 AW	210	(< (+ n 2) (cfa-k-count cfa))
987c1f5f AW	211	(eq? (cfa-k-sym cfa (+ n 2)) kargs))
987c1f5f AW	212	(emit-br asm kargs))))))
6e422a35 AW	213
	214	(define (compile-tail label exp)
	215	;; There are only three kinds of expressions in tail position:
	216	;; tail calls, multiple-value returns, and single-value returns.
	217	(match exp
	218	(($ $call proc args)
	219	(for-each (match-lambda
	220	((src . dst) (emit-mov asm dst src)))
	221	(lookup-parallel-moves label allocation))
	222	(let ((tail-slots (cdr (iota (1+ (length args))))))
	223	(for-each maybe-load-constant tail-slots args))
	224	(emit-tail-call asm (1+ (length args))))
987c1f5f AW	225	(($ $values ())
	226	(emit-reset-frame asm 1)
	227	(emit-return-values asm))
13085a82	228	(($ $values (arg))
987c1f5f	229	(if (maybe-slot arg)
13085a82 AW	230	(emit-return asm (slot arg))
	231	(begin
	232	(emit-load-constant asm 1 (constant arg))
	233	(emit-return asm 1))))
6e422a35	234	(($ $values args)
13085a82 AW	235	(for-each (match-lambda
	236	((src . dst) (emit-mov asm dst src)))
	237	(lookup-parallel-moves label allocation))
6e422a35	238	(let ((tail-slots (cdr (iota (1+ (length args))))))
6e422a35 AW	239	(for-each maybe-load-constant tail-slots args))
	240	(emit-reset-frame asm (1+ (length args)))
	241	(emit-return-values asm))
	242	(($ $primcall 'return (arg))
	243	(emit-return asm (slot arg)))))
	244
	245	(define (compile-value label exp dst nlocals)
	246	(match exp
6e422a35 AW	247	(($ $values (arg))
	248	(or (maybe-load-constant dst arg)
	249	(maybe-mov dst (slot arg))))
	250	(($ $void)
	251	(emit-load-constant asm dst unspecified))
	252	(($ $const exp)
	253	(emit-load-constant asm dst exp))
	254	(($ $fun src meta () ($ $cont k))
	255	(emit-load-static-procedure asm dst k))
	256	(($ $fun src meta free ($ $cont k))
	257	(emit-make-closure asm dst k (length free)))
	258	(($ $call proc args)
987c1f5f AW	259	(let* ((proc-slot (lookup-call-proc-slot label allocation))
	260	(nargs (1+ (length args)))
	261	(arg-slots (map (lambda (x) (+ x proc-slot)) (iota nargs))))
	262	(for-each (match-lambda
	263	((src . dst) (emit-mov asm dst src)))
	264	(lookup-parallel-moves label allocation))
	265	(for-each maybe-load-constant arg-slots (cons proc args))
	266	(emit-call asm proc-slot nargs)
fa48a2f7 AW	267	(cond
	268	(dst
	269	(emit-receive asm dst proc-slot nlocals))
	270	(else
	271	;; FIXME: Only allow more values if there is a rest arg.
	272	;; Express values truncation by the presence of an
	273	;; unused rest arg instead of implicitly.
	274	(emit-receive-values asm proc-slot #t 1)
	275	(emit-reset-frame asm nlocals)))))
6e422a35 AW	276	(($ $primcall 'current-module)
	277	(emit-current-module asm dst))
	278	(($ $primcall 'cached-toplevel-box (scope name bound?))
	279	(emit-cached-toplevel-box asm dst (constant scope) (constant name)
	280	(constant bound?)))
	281	(($ $primcall 'cached-module-box (mod name public? bound?))
	282	(emit-cached-module-box asm dst (constant mod) (constant name)
	283	(constant public?) (constant bound?)))
	284	(($ $primcall 'resolve (name bound?))
	285	(emit-resolve asm dst (constant bound?) (slot name)))
	286	(($ $primcall 'free-ref (closure idx))
	287	(emit-free-ref asm dst (slot closure) (constant idx)))
6e422a35	288	(($ $primcall 'vector-ref (vector index))
4c906ad5 AW	289	(emit-vector-ref asm dst (slot vector) (slot index)))
	290	(($ $primcall 'make-vector/immediate (length init))
	291	(emit-make-vector/immediate asm dst (constant length) (slot init)))
	292	(($ $primcall 'vector-ref/immediate (vector index))
	293	(emit-vector-ref/immediate asm dst (slot vector) (constant index)))
	294	(($ $primcall 'allocate-struct/immediate (vtable nfields))
	295	(emit-allocate-struct/immediate asm dst (slot vtable) (constant nfields)))
	296	(($ $primcall 'struct-ref/immediate (struct n))
	297	(emit-struct-ref/immediate asm dst (slot struct) (constant n)))
6e422a35 AW	298	(($ $primcall 'builtin-ref (name))
	299	(emit-builtin-ref asm dst (constant name)))
	300	(($ $primcall 'bv-u8-ref (bv idx))
	301	(emit-bv-u8-ref asm dst (slot bv) (slot idx)))
d59060ce AW	302	(($ $primcall 'bv-s8-ref (bv idx))
d59060ce AW	303	(emit-bv-s8-ref asm dst (slot bv) (slot idx)))
6e422a35 AW	304	(($ $primcall 'bv-u16-ref (bv idx))
	305	(emit-bv-u16-ref asm dst (slot bv) (slot idx)))
	306	(($ $primcall 'bv-s16-ref (bv idx))
	307	(emit-bv-s16-ref asm dst (slot bv) (slot idx)))
	308	(($ $primcall 'bv-u32-ref (bv idx val))
	309	(emit-bv-u32-ref asm dst (slot bv) (slot idx)))
	310	(($ $primcall 'bv-s32-ref (bv idx val))
	311	(emit-bv-s32-ref asm dst (slot bv) (slot idx)))
	312	(($ $primcall 'bv-u64-ref (bv idx val))
	313	(emit-bv-u64-ref asm dst (slot bv) (slot idx)))
	314	(($ $primcall 'bv-s64-ref (bv idx val))
	315	(emit-bv-s64-ref asm dst (slot bv) (slot idx)))
	316	(($ $primcall 'bv-f32-ref (bv idx val))
	317	(emit-bv-f32-ref asm dst (slot bv) (slot idx)))
	318	(($ $primcall 'bv-f64-ref (bv idx val))
	319	(emit-bv-f64-ref asm dst (slot bv) (slot idx)))
	320	(($ $primcall name args)
	321	;; FIXME: Inline all the cases.
691697de	322	(let ((inst (prim-instruction name)))
6e422a35 AW	323	(emit-text asm `((,inst ,dst ,@(map slot args))))))))
	324
	325	(define (compile-effect label exp k nlocals)
	326	(match exp
	327	(($ $values ()) #f)
7ab76a83	328	(($ $prompt escape? tag handler)
6e422a35 AW	329	(match (lookup-cont handler)
	330	(($ $ktrunc ($ $arity req () rest () #f) khandler-body)
	331	(let ((receive-args (gensym "handler"))
	332	(nreq (length req))
987c1f5f	333	(proc-slot (lookup-call-proc-slot handler allocation)))
6e422a35 AW	334	(emit-prompt asm (slot tag) escape? proc-slot receive-args)
	335	(emit-br asm k)
	336	(emit-label asm receive-args)
	337	(emit-receive-values asm proc-slot (->bool rest) nreq)
fa48a2f7 AW	338	(when (and rest
	339	(match (vector-ref contv (cfa-k-idx cfa khandler-body))
	340	(($ $kargs names (_ ... rest))
	341	(maybe-slot rest))))
6e422a35 AW	342	(emit-bind-rest asm (+ proc-slot 1 nreq)))
	343	(for-each (match-lambda
	344	((src . dst) (emit-mov asm dst src)))
	345	(lookup-parallel-moves handler allocation))
	346	(emit-reset-frame asm nlocals)
	347	(emit-br asm khandler-body)))))
	348	(($ $primcall 'cache-current-module! (sym scope))
	349	(emit-cache-current-module! asm (slot sym) (constant scope)))
	350	(($ $primcall 'free-set! (closure idx value))
	351	(emit-free-set! asm (slot closure) (slot value) (constant idx)))
	352	(($ $primcall 'box-set! (box value))
	353	(emit-box-set! asm (slot box) (slot value)))
4c906ad5 AW	354	(($ $primcall 'struct-set!/immediate (struct index value))
4c906ad5 AW	355	(emit-struct-set!/immediate asm (slot struct) (constant index) (slot value)))
6e422a35	356	(($ $primcall 'vector-set! (vector index value))
4c906ad5 AW	357	(emit-vector-set! asm (slot vector) (slot index) (slot value)))
	358	(($ $primcall 'vector-set!/immediate (vector index value))
	359	(emit-vector-set!/immediate asm (slot vector) (constant index)
	360	(slot value)))
6e422a35 AW	361	(($ $primcall 'variable-set! (var val))
	362	(emit-box-set! asm (slot var) (slot val)))
	363	(($ $primcall 'set-car! (pair value))
	364	(emit-set-car! asm (slot pair) (slot value)))
	365	(($ $primcall 'set-cdr! (pair value))
	366	(emit-set-cdr! asm (slot pair) (slot value)))
	367	(($ $primcall 'define! (sym value))
	368	(emit-define! asm (slot sym) (slot value)))
	369	(($ $primcall 'push-fluid (fluid val))
	370	(emit-push-fluid asm (slot fluid) (slot val)))
	371	(($ $primcall 'pop-fluid ())
	372	(emit-pop-fluid asm))
	373	(($ $primcall 'wind (winder unwinder))
	374	(emit-wind asm (slot winder) (slot unwinder)))
	375	(($ $primcall 'bv-u8-set! (bv idx val))
	376	(emit-bv-u8-set! asm (slot bv) (slot idx) (slot val)))
d59060ce AW	377	(($ $primcall 'bv-s8-set! (bv idx val))
d59060ce AW	378	(emit-bv-s8-set! asm (slot bv) (slot idx) (slot val)))
6e422a35 AW	379	(($ $primcall 'bv-u16-set! (bv idx val))
	380	(emit-bv-u16-set! asm (slot bv) (slot idx) (slot val)))
	381	(($ $primcall 'bv-s16-set! (bv idx val))
	382	(emit-bv-s16-set! asm (slot bv) (slot idx) (slot val)))
	383	(($ $primcall 'bv-u32-set! (bv idx val))
	384	(emit-bv-u32-set! asm (slot bv) (slot idx) (slot val)))
	385	(($ $primcall 'bv-s32-set! (bv idx val))
	386	(emit-bv-s32-set! asm (slot bv) (slot idx) (slot val)))
	387	(($ $primcall 'bv-u64-set! (bv idx val))
	388	(emit-bv-u64-set! asm (slot bv) (slot idx) (slot val)))
	389	(($ $primcall 'bv-s64-set! (bv idx val))
	390	(emit-bv-s64-set! asm (slot bv) (slot idx) (slot val)))
	391	(($ $primcall 'bv-f32-set! (bv idx val))
	392	(emit-bv-f32-set! asm (slot bv) (slot idx) (slot val)))
	393	(($ $primcall 'bv-f64-set! (bv idx val))
	394	(emit-bv-f64-set! asm (slot bv) (slot idx) (slot val)))
	395	(($ $primcall 'unwind ())
	396	(emit-unwind asm))))
	397
	398	(define (compile-values label exp syms)
	399	(match exp
	400	(($ $values args)
	401	(for-each (match-lambda
	402	((src . dst) (emit-mov asm dst src)))
	403	(lookup-parallel-moves label allocation))
	404	(for-each maybe-load-constant (map slot syms) args))))
	405
	406	(define (compile-test label exp kt kf next-label)
	407	(define (unary op sym)
	408	(cond
	409	((eq? kt next-label)
	410	(op asm (slot sym) #t kf))
	411	(else
	412	(op asm (slot sym) #f kt)
	413	(unless (eq? kf next-label)
	414	(emit-br asm kf)))))
	415	(define (binary op a b)
	416	(cond
	417	((eq? kt next-label)
	418	(op asm (slot a) (slot b) #t kf))
	419	(else
	420	(op asm (slot a) (slot b) #f kt)
	421	(unless (eq? kf next-label)
	422	(emit-br asm kf)))))
	423	(match exp
58ef5f07 AW	424	(($ $values (sym))
	425	(call-with-values (lambda ()
	426	(lookup-maybe-constant-value sym allocation))
	427	(lambda (has-const? val)
	428	(if has-const?
	429	(if val
	430	(unless (eq? kt next-label)
	431	(emit-br asm kt))
	432	(unless (eq? kf next-label)
	433	(emit-br asm kf)))
	434	(unary emit-br-if-true sym)))))
6e422a35 AW	435	(($ $primcall 'null? (a)) (unary emit-br-if-null a))
	436	(($ $primcall 'nil? (a)) (unary emit-br-if-nil a))
	437	(($ $primcall 'pair? (a)) (unary emit-br-if-pair a))
	438	(($ $primcall 'struct? (a)) (unary emit-br-if-struct a))
	439	(($ $primcall 'char? (a)) (unary emit-br-if-char a))
	440	(($ $primcall 'symbol? (a)) (unary emit-br-if-symbol a))
	441	(($ $primcall 'variable? (a)) (unary emit-br-if-variable a))
	442	(($ $primcall 'vector? (a)) (unary emit-br-if-vector a))
	443	(($ $primcall 'string? (a)) (unary emit-br-if-string a))
	444	(($ $primcall 'bytevector? (a)) (unary emit-br-if-bytevector a))
	445	;; Add more TC7 tests here. Keep in sync with
	446	;; branching-primcall-arities in (language cps primitives) and
	447	;; the set of macro-instructions in assembly.scm.
	448	(($ $primcall 'eq? (a b)) (binary emit-br-if-eq a b))
	449	(($ $primcall 'eqv? (a b)) (binary emit-br-if-eqv a b))
	450	(($ $primcall 'equal? (a b)) (binary emit-br-if-equal a b))
	451	(($ $primcall '< (a b)) (binary emit-br-if-< a b))
	452	(($ $primcall '<= (a b)) (binary emit-br-if-<= a b))
	453	(($ $primcall '= (a b)) (binary emit-br-if-= a b))
	454	(($ $primcall '>= (a b)) (binary emit-br-if-<= b a))
	455	(($ $primcall '> (a b)) (binary emit-br-if-< b a))))
	456
fa48a2f7	457	(define (compile-trunc label k exp nreq rest-var nlocals)
6e422a35 AW	458	(match exp
6e422a35 AW	459	(($ $call proc args)
987c1f5f AW	460	(let* ((proc-slot (lookup-call-proc-slot label allocation))
	461	(nargs (1+ (length args)))
	462	(arg-slots (map (lambda (x) (+ x proc-slot)) (iota nargs))))
	463	(for-each (match-lambda
	464	((src . dst) (emit-mov asm dst src)))
	465	(lookup-parallel-moves label allocation))
	466	(for-each maybe-load-constant arg-slots (cons proc args))
	467	(emit-call asm proc-slot nargs)
	468	;; FIXME: Only allow more values if there is a rest arg.
	469	;; Express values truncation by the presence of an
	470	;; unused rest arg instead of implicitly.
	471	(emit-receive-values asm proc-slot #t nreq)
fa48a2f7	472	(when (and rest-var (maybe-slot rest-var))
987c1f5f AW	473	(emit-bind-rest asm (+ proc-slot 1 nreq)))
	474	(for-each (match-lambda
	475	((src . dst) (emit-mov asm dst src)))
	476	(lookup-parallel-moves k allocation))
	477	(emit-reset-frame asm nlocals)))))
6e422a35 AW	478
	479	(match f
	480	(($ $fun src meta free ($ $cont k ($ $kentry self tail clauses)))
	481	;; FIXME: src on kentry instead?
	482	(when src
	483	(emit-source asm src))
	484	(compile-entry (or meta '()))))))
d258fccc	485
6e8ad823 AW	486	(define (visit-funs proc exp)
6e8ad823 AW	487	(match exp
6e422a35	488	(($ $continue _ _ exp)
6e8ad823 AW	489	(visit-funs proc exp))
6e8ad823 AW	490
6e422a35	491	(($ $fun src meta free body)
6e8ad823 AW	492	(proc exp)
	493	(visit-funs proc body))
	494
	495	(($ $letk conts body)
	496	(visit-funs proc body)
	497	(for-each (lambda (cont) (visit-funs proc cont)) conts))
	498
6e422a35	499	(($ $cont sym ($ $kargs names syms body))
6e8ad823 AW	500	(visit-funs proc body))
6e8ad823 AW	501
6e422a35	502	(($ $cont sym ($ $kclause arity body))
6e8ad823 AW	503	(visit-funs proc body))
6e8ad823 AW	504
6e422a35	505	(($ $cont sym ($ $kentry self tail clauses))
6e8ad823 AW	506	(for-each (lambda (clause) (visit-funs proc clause)) clauses))
	507
	508	(_ (values))))
	509
691697de	510	(define (compile-bytecode exp env opts)
6e8ad823 AW	511	(let* ((exp (fix-arities exp))
	512	(exp (optimize exp opts))
	513	(exp (convert-closures exp))
	514	(exp (reify-primitives exp))
	515	(asm (make-assembler)))
	516	(visit-funs (lambda (fun)
	517	(compile-fun fun asm))
	518	exp)
	519	(values (link-assembly asm #:page-aligned? (kw-arg-ref opts #:to-file? #f))
	520	env
	521	env)))