racket/collects/compiler/zo-parse.ss
Matthew Flatt 76cf25fc12 document 'mzc --decompile'
svn: r11317
2008-08-19 00:50:52 +00:00

698 lines
24 KiB
Scheme

#lang scheme
(require mzlib/etc
scheme/list)
(provide zo-parse)
;; ----------------------------------------
;; Structures to represent bytecode
(define-syntax-rule (define-form-struct id (field-id ...))
(begin
(define-struct id (field-id ...) #:transparent)
(provide (struct-out id))))
(define-form-struct compilation-top (max-let-depth prefix code)) ; compiled code always wrapped with this
(define-form-struct prefix (num-lifts toplevels stxs)) ; sets up top-level and syntax-object array
;; In toplevels of resove prefix:
(define-form-struct global-bucket (name)) ; top-level binding
(define-form-struct module-variable (modidx sym pos phase)) ; direct access to exported id
;; In stxs of prefix:
(define-form-struct stx (encoded)) ; todo: decode syntax objects
(define-form-struct mod (name self-modidx prefix provides requires body syntax-body))
(define-form-struct lam (name flags num-params rest? closure-map max-let-depth body)) ; `lambda'
(define-form-struct closure (code gen-id)) ; a static closure (nothing to close over)
(define-form-struct case-lam (name clauses)) ; each clause is an lam
(define-form-struct let-one (rhs body)) ; pushes one value onto stack
(define-form-struct let-void (count boxes? body)) ; create new stack slots
(define-form-struct install-value (count pos boxes? rhs body)) ; set existing stack slot(s)
(define-form-struct let-rec (procs body)) ; put `letrec'-bound closures into existing stack slots
(define-form-struct boxenv (pos body)) ; box existing stack element
(define-form-struct localref (unbox? offset clear?)) ; access local via stack
(define-form-struct toplevel (depth pos const? mutated?)) ; access binding via prefix array (which is on stack)
(define-form-struct topsyntax (depth pos midpt)) ; access syntax object via prefix array (which is on stack)
(define-form-struct application (rator rands)) ; function call
(define-form-struct branch (test then else)) ; `if'
(define-form-struct with-cont-mark (key val body)) ; `with-continuation-mark'
(define-form-struct beg0 (seq)) ; `begin0'
(define-form-struct sequence (forms)) ; `begin'
(define-form-struct splice (forms)) ; top-level `begin'
(define-form-struct varref (toplevel)) ; `#%variable-reference'
(define-form-struct assign (id rhs undef-ok?)) ; top-level or module-level set!
(define-form-struct apply-values (proc args-expr)) ; `(call-with-values (lambda () ,args-expr) ,proc)
(define-form-struct primitive (id)) ; direct preference to a kernel primitive
;; Definitions (top level or within module):
(define-form-struct def-values (ids rhs))
(define-form-struct def-syntaxes (ids rhs prefix max-let-depth))
(define-form-struct def-for-syntax (ids rhs prefix max-let-depth))
;; Top-level `require'
(define-form-struct req (reqs dummy))
;; A static closure can refer directly to itself, creating a cycle
(define-struct indirect ([v #:mutable]) #:prefab)
(provide (struct-out indirect))
;; ----------------------------------------
;; Bytecode unmarshalers for various forms
(define (read-toplevel v)
(define SCHEME_TOPLEVEL_CONST #x01)
(define SCHEME_TOPLEVEL_MUTATED #x02)
(match v
[(cons depth (cons pos flags))
(make-toplevel depth pos
(positive? (bitwise-and flags SCHEME_TOPLEVEL_CONST))
(positive? (bitwise-and flags SCHEME_TOPLEVEL_MUTATED)))]
[(cons depth pos)
(make-toplevel depth pos #f #f)]))
(define (read-topsyntax v)
(match v
[`(,depth ,pos . ,midpt)
(make-topsyntax depth pos midpt)]))
(define (read-variable v)
(if (symbol? v)
(make-global-bucket v)
(let-values ([(phase modname varname)
(match v
[(list* phase modname varname)
(values phase modname varname)]
[(list* modname varname)
(values 0 modname varname)])])
(if (and (zero? phase) (eq? modname '#%kernel))
(error 'bucket "var ~a" varname)
(make-module-variable modname varname -1 phase)))))
(define (read-compilation-top v)
(match v
[`(,ld ,prefix . ,code)
(unless (prefix? prefix)
(error 'bad "not prefix ~a" prefix))
(make-compilation-top ld prefix code)]))
(define (read-resolve-prefix v)
(match v
[`(,i ,tv . ,sv)
(make-prefix i (vector->list tv) (vector->list sv))]))
(define (read-unclosed-procedure v)
(define CLOS_HAS_REST 1)
(define CLOS_HAS_REF_ARGS 2)
(match v
[`(,flags ,num-params ,max-let-depth ,name ,v . ,rest)
(let ([rest? (positive? (bitwise-and flags CLOS_HAS_REST))])
(let-values ([(closure-size closed-over body)
(if (zero? (bitwise-and flags CLOS_HAS_REF_ARGS))
(values (vector-length v) v rest)
(values v (car rest) (cdr rest)))])
(make-lam name
flags
((if rest? sub1 values) num-params)
rest?
(if (= closure-size (vector-length closed-over))
closed-over
(let ([v2 (make-vector closure-size)])
(vector-copy! v2 0 closed-over 0 closure-size)
v2))
max-let-depth
body)))]))
(define (read-let-value v)
(match v
[`(,count ,pos ,boxes? ,rhs . ,body)
(make-install-value count pos boxes? rhs body)]))
(define (read-let-void v)
(match v
[`(,count ,boxes? . ,body)
(make-let-void count boxes? body)]))
(define (read-letrec v)
(match v
[`(,count ,body . ,procs)
(make-let-rec procs body)]))
(define (read-with-cont-mark v)
(match v
[`(,key ,val . ,body)
(make-with-cont-mark key val body)]))
(define (read-sequence v)
(make-sequence v))
(define (read-define-values v)
(make-def-values
(cdr (vector->list v))
(vector-ref v 0)))
(define (read-define-syntaxes mk v)
(mk (list-tail (vector->list v) 4)
(vector-ref v 0)
(vector-ref v 1)
(vector-ref v 2)
#;(vector-ref v 3)))
(define (read-define-syntax v)
(read-define-syntaxes make-def-syntaxes v))
(define (read-define-for-syntax v)
(read-define-syntaxes make-def-for-syntax v))
(define (read-set! v)
(make-assign (cadr v) (cddr v) (car v)))
(define (read-case-lambda v)
(make-case-lam (car v) (cdr v)))
(define (read-begin0 v)
(match v
[(struct sequence (exprs))
(make-beg0 exprs)]))
(define (read-boxenv v)
(make-boxenv (car v) (cdr v)))
(define (read-require v)
(make-req (cdr v) (car v)))
(define (read-#%variable-ref v)
(make-varref v))
(define (read-apply-values v)
(make-apply-values (car v) (cdr v)))
(define (read-splice v)
(make-splice v))
(define (read-module v)
(match v
[`(,name ,self-modidx ,functional? ,et-functional?
,rename ,max-let-depth ,dummy
,prefix ,kernel-exclusion ,reprovide-kernel?
,indirect-provides ,num-indirect-provides ,protects
,provide-phase-count . ,rest)
(let ([phase-data (take rest (* 8 provide-phase-count))])
(match (list-tail rest (* 8 provide-phase-count))
[`(,syntax-body ,body
,requires ,syntax-requires ,template-requires ,label-requires
,more-requires-count . ,more-requires)
(make-mod name self-modidx
prefix phase-data
(list*
(cons 0 requires)
(cons 1 syntax-requires)
(cons -1 template-requires)
(cons #f label-requires)
more-requires)
(vector->list body)
(map (lambda (sb)
(match sb
[`#(,ids ,expr ,max-let-depth ,prefix ,for-stx?)
((if for-stx?
make-def-for-syntax
make-def-syntaxes)
ids expr prefix max-let-depth)]))
(vector->list syntax-body)))]))]))
(define (read-module-wrap v)
v)
;; ----------------------------------------
;; Unmarshal dispatch for various types
(define (read-more-syntax v)
(let ([id (car v)]
[v (cdr v)])
;; This is the ..._EXPD mapping from "schpriv.h":
(case id
[(0) (read-define-values v)]
[(1) (read-define-syntax v)]
[(2) (read-set! v)]
[(3) v] ; a case-lam already
[(4) (read-begin0 v)]
[(5) (read-boxenv v)]
[(6) (read-module-wrap v)]
[(7) (read-require v)]
[(8) (read-define-for-syntax v)]
[(9) (read-#%variable-ref v)]
[(10) (read-apply-values v)]
[(11) (read-splice v)]
[else (error 'read-mode-unsyntax "unknown id: ~e" id)])))
;; Type mappings from "stypes.h":
(define (int->type i)
(case i
[(0) 'toplevel-type]
[(3) 'syntax-type]
[(7) 'sequence-type]
[(9) 'unclosed-procedure-type]
[(10) 'let-value-type]
[(11) 'let-void-type]
[(12) 'letrec-type]
[(14) 'with-cont-mark-type]
[(15) 'quote-syntax-type]
[(24) 'variable-type]
[(25) 'module-variable-type]
[(96) 'case-lambda-sequence-type]
[(97) 'begin0-sequence-type]
[(100) 'module-type]
[(103) 'resolve-prefix-type]
[else (error 'int->type "unknown type: ~e" i)]))
(define type-readers
(make-immutable-hash
(list
(cons 'toplevel-type read-toplevel)
(cons 'syntax-type read-more-syntax)
(cons 'sequence-type read-sequence)
(cons 'unclosed-procedure-type read-unclosed-procedure)
(cons 'let-value-type read-let-value)
(cons 'let-void-type read-let-void)
(cons 'letrec-type read-letrec)
(cons 'with-cont-mark-type read-with-cont-mark)
(cons 'quote-syntax-type read-topsyntax)
(cons 'variable-type read-variable)
(cons 'module-variable-type read-variable)
(cons 'compilation-top-type read-compilation-top)
(cons 'case-lambda-sequence-type read-case-lambda)
(cons 'begin0-sequence-type read-sequence)
(cons 'module-type read-module)
(cons 'resolve-prefix-type read-resolve-prefix))))
(define (get-reader type)
(or (hash-ref type-readers type #f)
(lambda (v)
(error 'read-marshalled "reader for ~a not implemented" type))))
;; ----------------------------------------
;; Lowest layer of bytecode parsing
(define (split-so all-short so)
(define n (if (zero? all-short) 4 2))
(let loop ([so so])
(if (zero? (bytes-length so))
null
(cons (integer-bytes->integer (subbytes so 0 n) #f)
(loop (subbytes so n))))))
(define (read-simple-number p)
;; not sure if it's really unsigned
(integer-bytes->integer (read-bytes 4 p) #f #f))
(define-struct cport ([pos #:mutable] orig-port size bytes symtab shared-offsets))
(define (cp-getc cp)
(begin-with-definitions
(when ((cport-pos cp) . >= . (cport-size cp))
(error "off the end"))
(define r
(bytes-ref (cport-bytes cp) (cport-pos cp)))
(set-cport-pos! cp (add1 (cport-pos cp)))
r))
(define small-list-max 65)
(define cpt-table
;; The "schcpt.h" mapping
`([0 escape]
[1 symbol]
[2 symref]
[3 weird-symbol]
[4 keyword]
[5 byte-string]
[6 string]
[7 char]
[8 int]
[9 null]
[10 true]
[11 false]
[12 void]
[13 box]
[14 pair]
[15 list]
[16 vector]
[17 hash-table]
[18 stx]
[19 gstx] ; unused
[20 marshalled]
[21 quote]
[22 reference]
[23 local]
[24 local-unbox]
[25 svector]
[26 application]
[27 let-one]
[28 branch]
[29 module-index]
[30 module-var]
[31 path]
[32 closure]
[33 delayed]
[34 prefab]
[35 60 small-number]
[60 80 small-symbol]
[80 92 small-marshalled]
[92 ,(+ 92 small-list-max) small-proper-list]
[,(+ 92 small-list-max) 192 small-list]
[192 207 small-local]
[207 222 small-local-unbox]
[222 247 small-svector]
[248 small-application2]
[249 small-application3]
[247 255 small-application]))
(define (cpt-table-lookup i)
(for/or ([ent cpt-table])
(match ent
[(list k sym) (and (= k i) (cons k sym))]
[(list k k* sym)
(and (<= k i)
(< i k*)
(cons k sym))])))
(define (read-compact-bytes port c)
(begin0
(subbytes (cport-bytes port) (cport-pos port) (+ (cport-pos port) c))
(set-cport-pos! port (+ c (cport-pos port)))))
(define (read-compact-chars port c)
(bytes->string/utf-8 (read-compact-bytes port c)))
(define (read-compact-list c proper port)
(cond [(= 0 c)
(if proper null (read-compact port))]
[else (cons (read-compact port) (read-compact-list (sub1 c) proper port))]))
(define (read-compact-number port)
(define flag (cp-getc port))
(cond [(< flag 128)
flag]
[(zero? (bitwise-and flag #x40))
(let ([a (cp-getc port)])
(+ (a . << . 6) (bitwise-and flag 63)))]
[(zero? (bitwise-and flag #x20))
(- (bitwise-and flag #x1F))]
[else
(let ([a (cp-getc port)]
[b (cp-getc port)]
[c (cp-getc port)]
[d (cp-getc port)])
(let ([n (integer-bytes->integer (bytes a b c d) #f #f)])
(if (zero? (bitwise-and flag #x10))
(- n)
n)))]))
(define (read-compact-svector port n)
(list->vector (reverse (for/list ([i (in-range n)]) (read-compact-number port)))))
(define (read-marshalled type port)
(let* ([type (if (number? type) (int->type type) type)]
[l (read-compact port)]
[reader (get-reader type)])
(reader l)))
(define (make-local unbox? pos flags)
(define SCHEME_LOCAL_CLEAR_ON_READ #x01)
(make-localref unbox? pos (positive? (bitwise-and flags SCHEME_LOCAL_CLEAR_ON_READ))))
(define (a . << . b)
(arithmetic-shift a b))
(define-struct not-ready ())
;; ----------------------------------------
;; Main parsing loop
(define (read-compact cp)
(let loop ([need-car 0] [proper #f] [last #f] [first #f])
(begin-with-definitions
(define ch (cp-getc cp))
(define-values (cpt-start cpt-tag) (let ([x (cpt-table-lookup ch)])
(unless x
(error 'read-compact "unknown code : ~a" ch))
(values (car x) (cdr x))))
(define v
(case cpt-tag
[(delayed)
(let ([pos (read-compact-number cp)])
(let ([v (vector-ref (cport-symtab cp) pos)])
(if (not-ready? v)
(let ([save-pos (cport-pos cp)])
(set-cport-pos! cp (vector-ref (cport-shared-offsets cp) (sub1 pos)))
(let ([v (read-compact cp)])
(vector-set! (cport-symtab cp) pos v)
(set-cport-pos! cp save-pos)
v))
v)))]
[(escape)
(let* ([len (read-compact-number cp)]
[s (subbytes (cport-bytes cp) (cport-pos cp) (+ (cport-pos cp) len))])
(set-cport-pos! cp (+ (cport-pos cp) len))
(parameterize ([read-accept-compiled #t]
[read-accept-bar-quote #t]
[read-accept-box #t]
[read-accept-graph #t]
[read-case-sensitive #t]
[read-square-bracket-as-paren #t]
[read-curly-brace-as-paren #t]
[read-decimal-as-inexact #t]
[read-accept-dot #t]
[read-accept-infix-dot #t]
[read-accept-quasiquote #t])
(read (open-input-bytes s))))]
[(reference)
(make-primitive (read-compact-number cp))]
[(small-list small-proper-list)
(let* ([l (- ch cpt-start)]
[ppr (eq? cpt-tag 'small-proper-list)])
(if (positive? need-car)
(if (= l 1)
(cons (read-compact cp)
(if ppr null (read-compact cp)))
(read-compact-list l ppr cp))
(loop l ppr last first)))]
[(let-one)
(make-let-one (read-compact cp) (read-compact cp))]
[(branch)
(make-branch (read-compact cp) (read-compact cp) (read-compact cp))]
[(module-index) (module-path-index-join (read-compact cp) (read-compact cp))]
[(module-var)
(let ([mod (read-compact cp)]
[var (read-compact cp)]
[pos (read-compact-number cp)])
(make-module-variable mod var pos 0))]
[(local-unbox)
(let* ([p* (read-compact-number cp)]
[p (if (< p* 0)
(- (add1 p*))
p*)]
[flags (if (< p* 0)
(read-compact-number cp)
0)])
(make-local #t p flags))]
[(path)
(let* ([p (bytes->path (read-compact-bytes cp (read-compact-number cp)))])
(if (relative-path? p)
(path->complete-path p (or (current-load-relative-directory)
(current-directory)))
p))]
[(small-number)
(let ([l (- ch cpt-start)])
l)]
[(int)
(read-compact-number cp)]
[(false) #f]
[(true) #t]
[(null) null]
[(void) (void)]
[(vector) (let* ([n (read-compact-number cp)]
[lst (for/list ([i (in-range n)])
(read-compact cp))])
(vector->immutable-vector (list->vector lst)))]
[(list) (let* ([n (read-compact-number cp)])
(for/list ([i (in-range n)])
(read-compact cp)))]
[(prefab)
(let ([v (read-compact cp)])
(apply make-prefab-struct
(vector-ref v 0)
(cdr (vector->list v))))]
[(hash-table)
(let ([eq (read-compact-number cp)]
[len (read-compact-number cp)])
((if (zero? eq)
make-hash-placeholder
make-hasheq-placeholder)
(for/list ([i (in-range len)])
(cons (read-compact cp)
(read-compact cp)))))]
[(marshalled) (read-marshalled (read-compact-number cp) cp)]
[(stx)
(let ([v (make-reader-graph (read-compact cp))])
(make-stx v))]
[(local local-unbox)
(let ([c (read-compact-number cp)]
[unbox? (eq? cpt-tag 'local-unbox)])
(if (negative? c)
(make-local unbox? (- (add1 c)) (read-compact-number cp))
(make-local unbox? c 0)))]
[(small-local)
(make-local #f (- ch cpt-start) 0)]
[(small-local-unbox)
(make-local #t (- ch cpt-start) 0)]
[(small-symbol)
(let ([l (- ch cpt-start)])
(string->symbol (read-compact-chars cp l)))]
[(symbol)
(let ([l (read-compact-number cp)])
(string->symbol (read-compact-chars cp l)))]
[(keyword)
(let ([l (read-compact-number cp)])
(string->keyword (read-compact-chars cp l)))]
[(byte-string)
(let ([l (read-compact-number cp)])
(read-compact-bytes cp l))]
[(string)
(let ([l (read-compact-number cp)]
[cl (read-compact-number cp)])
(read-compact-chars cp l))]
[(char)
(integer->char (read-compact-number cp))]
[(box)
(box (read-compact cp))]
[(quote)
(make-reader-graph (read-compact cp))]
[(symref)
(let* ([l (read-compact-number cp)]
[v (vector-ref (cport-symtab cp) l)])
(if (not-ready? v)
(let ([pos (cport-pos cp)])
(set-cport-pos! cp (vector-ref (cport-shared-offsets cp) (sub1 l)))
(let ([v (read-compact cp)])
(set-cport-pos! cp pos)
(vector-set! (cport-symtab cp) l v)
v))
v))]
[(weird-symbol)
(let ([u (read-compact-number cp)]
[str (read-compact-chars cp (read-compact-number cp))])
;; FIXME: no way to construct quasi-interned symbols:
(string->uninterned-symbol str))]
[(small-marshalled)
(read-marshalled (- ch cpt-start) cp)]
[(small-application2)
(make-application (read-compact cp)
(list (read-compact cp)))]
[(small-application3)
(make-application (read-compact cp)
(list (read-compact cp)
(read-compact cp)))]
[(small-application)
(let ([c (add1 (- ch cpt-start))])
(make-application (read-compact cp)
(for/list ([i (in-range (sub1 c))])
(read-compact cp))))]
[(application)
(let ([c (read-compact-number cp)])
(make-application (read-compact cp)
(for/list ([i (in-range c)])
(read-compact cp))))]
[(closure)
(let* ([l (read-compact-number cp)]
[ind (make-indirect #f)])
(vector-set! (cport-symtab cp) l ind)
(let* ([v (read-compact cp)]
[cl (make-closure v (gensym
(let ([s (lam-name v)])
(cond
[(symbol? s) s]
[(vector? s) (vector-ref s 0)]
[else 'closure]))))])
(vector-set! (cport-symtab cp) l cl)
(set-indirect-v! ind cl)
cl))]
[(svector)
(read-compact-svector cp (read-compact-number cp))]
[(small-svector)
(read-compact-svector cp (- ch cpt-start))]
[else (error 'read-compact "unknown tag ~a" cpt-tag)]))
(cond
[(zero? need-car) v]
[(and proper (= need-car 1))
(cons v null)]
[else
(cons v (loop (sub1 need-car) proper last first))]))))
;; path -> bytes
;; implementes read.c:read_compiled
(define (zo-parse port)
(begin-with-definitions
;; skip the "#~"
(unless (equal? #"#~" (read-bytes 2 port))
(error 'zo-parse "not a bytecode stream"))
(define version (read-bytes (min 63 (read-byte port)) port))
(define symtabsize (read-simple-number port))
(define all-short (read-byte port))
(define cnt (* (if (not (zero? all-short)) 2 4)
(sub1 symtabsize)))
(define so (read-bytes cnt port))
(define so* (list->vector (split-so all-short so)))
(define shared-size (read-simple-number port))
(define size* (read-simple-number port))
(when (shared-size . >= . size*)
(error 'bad-read))
(define rst (read-bytes size* port))
(unless (eof-object? (read port))
(error 'not-end))
(unless (= size* (bytes-length rst))
(error "wrong number of bytes"))
(define symtab (make-vector symtabsize (make-not-ready)))
(define cp (make-cport 0 port size* rst symtab so*))
(for/list ([i (in-range 1 symtabsize)])
(when (not-ready? (vector-ref symtab i))
(set-cport-pos! cp (vector-ref so* (sub1 i)))
(let ([v (read-compact cp)])
(vector-set! symtab i v))))
(set-cport-pos! cp shared-size)
(read-marshalled 'compilation-top-type cp)))
;; ----------------------------------------
#;
(begin
(define (compile/write sexp)
(define s (open-output-bytes))
(write (parameterize ([current-namespace (make-base-namespace)])
(eval '(require (for-syntax scheme/base)))
(compile sexp))
s)
(get-output-bytes s))
(define (compile/parse sexp)
(let* ([bs (compile/write sexp)]
[p (open-input-bytes bs)])
(zo-parse p)))
#;(compile/parse #s(foo 10 13))
(zo-parse (open-input-file "/home/mflatt/proj/plt/collects/scheme/private/compiled/more-scheme_ss.zo"))
)