ikarus/scheme/ikarus.fasl.write.ss

356 lines
12 KiB
Scheme

;;; Ikarus Scheme -- A compiler for R6RS Scheme.
;;; Copyright (C) 2006,2007 Abdulaziz Ghuloum
;;;
;;; This program is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License version 3 as
;;; published by the Free Software Foundation.
;;;
;;; This program 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
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program. If not, see <http://www.gnu.org/licenses/>.
(library (ikarus fasl write)
(export fasl-write)
(import
(rnrs hashtables)
(ikarus system $codes)
(ikarus system $pairs)
(ikarus system $structs)
(ikarus system $bytevectors)
(ikarus system $fx)
(ikarus system $chars)
(ikarus system $strings)
(ikarus system $flonums)
(ikarus system $bignums)
(except (ikarus code-objects) procedure-annotation)
(except (ikarus) fasl-write write-byte))
(module (wordsize)
(include "ikarus.config.ss"))
(define-syntax fxshift
(identifier-syntax
(case wordsize
[(4) 2]
[(8) 3]
[else (error 'fxshift "invalid wordsize" wordsize)])))
(define-syntax intbits (identifier-syntax (* wordsize 8)))
(define-syntax fxbits (identifier-syntax (- intbits fxshift)))
(define (fx? x)
(and (or (fixnum? x) (bignum? x))
(<= (- (expt 2 (- fxbits 1)))
x
(- (expt 2 (- fxbits 1)) 1))))
(define (int? x)
(and (or (fixnum? x) (bignum? x))
(<= (- (expt 2 (- intbits 1)))
x
(- (expt 2 (- intbits 1)) 1))))
(define-syntax write-byte
(syntax-rules ()
[(_ byte port)
(put-u8 port byte)]))
(define (put-tag c p)
(write-byte (char->integer c) p))
(define write-int32
(lambda (x p)
(write-byte (bitwise-and x #xFF) p)
(write-byte (bitwise-and (sra x 8) #xFF) p)
(write-byte (bitwise-and (sra x 16) #xFF) p)
(write-byte (bitwise-and (sra x 24) #xFF) p)))
(define write-int
(lambda (x p)
(unless (int? x) (die 'write-int "not a int" x))
(write-int32 x p)
(when (eqv? wordsize 8)
(write-int32 (sra x 32) p))))
(define fasl-write-immediate
(lambda (x p)
(cond
[(null? x) (put-tag #\N p)]
[(fx? x)
(put-tag #\I p)
(write-int (bitwise-arithmetic-shift-left x fxshift) p)]
[(char? x)
(let ([n ($char->fixnum x)])
(if ($fx<= n 255)
(begin
(put-tag #\c p)
(write-byte n p))
(begin
(put-tag #\C p)
(write-int32 n p))))]
[(boolean? x)
(put-tag (if x #\T #\F) p)]
[(eof-object? x) (put-tag #\E p)]
[(eq? x (void)) (put-tag #\U p)]
[else (die 'fasl-write "not a fasl-writable immediate" x)])))
(define (ascii-string? s)
(let f ([s s] [i 0] [n (string-length s)])
(or ($fx= i n)
(and ($char<= ($string-ref s i) ($fixnum->char 127))
(f s ($fxadd1 i) n)))))
(define (count-unshared-cdrs x h n)
(cond
[(and (pair? x) (eq? (hashtable-ref h x #f) 0))
(count-unshared-cdrs ($cdr x) h ($fxadd1 n))]
[else n]))
(define (write-pairs x p h m n)
(cond
[($fx= n 0) (fasl-write-object x p h m)]
[else
(write-pairs (cdr x) p h
(fasl-write-object (car x) p h m)
($fxsub1 n))]))
(define do-write
(lambda (x p h m)
(cond
[(pair? x)
(let ([d ($cdr x)])
(let ([n (count-unshared-cdrs d h 0)])
(cond
[($fx= n 0)
(put-tag #\P p)
(fasl-write-object d p h
(fasl-write-object (car x) p h m))]
[else
(cond
[($fx<= n 255)
(put-tag #\l p)
(write-byte n p)]
[else
(put-tag #\L p)
(write-int n p)])
(write-pairs d p h
(fasl-write-object (car x) p h m)
n)])))]
[(vector? x)
(put-tag #\V p)
(write-int (vector-length x) p)
(let f ([x x] [i 0] [n (vector-length x)] [m m])
(cond
[(fx= i n) m]
[else
(f x (fxadd1 i) n
(fasl-write-object (vector-ref x i) p h m))]))]
[(string? x)
(cond
[(ascii-string? x)
(put-tag #\s p)
(write-int (string-length x) p)
(let f ([x x] [i 0] [n (string-length x)])
(unless (fx= i n)
(write-byte (char->integer (string-ref x i)) p)
(f x (fxadd1 i) n)))]
[else
(put-tag #\S p)
(write-int (string-length x) p)
(let f ([x x] [i 0] [n (string-length x)])
(unless (= i n)
(write-int32 (char->integer (string-ref x i)) p)
(f x (fxadd1 i) n)))])
m]
[(gensym? x)
(put-tag #\G p)
(fasl-write-object (gensym->unique-string x) p h
(fasl-write-object (symbol->string x) p h m))]
[(symbol? x)
(put-tag #\M p)
(fasl-write-object (symbol->string x) p h m)]
[(code? x)
(put-tag #\x p)
(write-int (code-size x) p)
(write-int (bitwise-arithmetic-shift-left
(code-freevars x)
fxshift)
p)
(let ([m (fasl-write-object ($code-annotation x) p h m)])
(let f ([i 0] [n (code-size x)])
(unless (fx= i n)
(write-byte (code-ref x i) p)
(f (fxadd1 i) n)))
(fasl-write-object (code-reloc-vector x) p h m))]
[(struct? x)
(let ([rtd (struct-type-descriptor x)])
(cond
[(eq? rtd (base-rtd))
;;; rtd record
(put-tag #\R p)
(let ([names (struct-type-field-names x)]
[m
(fasl-write-object (struct-type-symbol x) p h
(fasl-write-object (struct-type-name x) p h m))])
(write-int (length names) p)
(let f ([names names] [m m])
(cond
[(null? names) m]
[else
(f (cdr names)
(fasl-write-object (car names) p h m))])))]
[else
;;; non-rtd record
(put-tag #\{ p)
(write-int (length (struct-type-field-names rtd)) p)
(let f ([names (struct-type-field-names rtd)]
[m (fasl-write-object rtd p h m)])
(cond
[(null? names) m]
[else
(f (cdr names)
(fasl-write-object
((struct-field-accessor rtd (car names)) x)
p h m))]))]))]
[(procedure? x)
(put-tag #\Q p)
(fasl-write-object ($closure-code x) p h m)]
[(bytevector? x)
(put-tag #\v p)
(let ([n ($bytevector-length x)])
(write-int n p)
(write-bytevector x 0 n p))
m]
[(flonum? x)
(put-tag #\f p)
(write-byte ($flonum-u8-ref x 7) p)
(write-byte ($flonum-u8-ref x 6) p)
(write-byte ($flonum-u8-ref x 5) p)
(write-byte ($flonum-u8-ref x 4) p)
(write-byte ($flonum-u8-ref x 3) p)
(write-byte ($flonum-u8-ref x 2) p)
(write-byte ($flonum-u8-ref x 1) p)
(write-byte ($flonum-u8-ref x 0) p)
m]
[(ratnum? x)
(put-tag #\r p)
(fasl-write-object (numerator x) p h
(fasl-write-object (denominator x) p h m))]
[(bignum? x)
(put-tag #\b p)
(let ([sz ($bignum-size x)])
(write-int (if ($bignum-positive? x) sz (- sz)) p)
(let f ([i 0])
(unless (fx= i sz)
(write-byte ($bignum-byte-ref x i) p)
(f (fxadd1 i)))))
m]
[else (die 'fasl-write "not fasl-writable" x)])))
(define (write-bytevector x i j p)
(unless ($fx= i j)
(write-byte ($bytevector-u8-ref x i) p)
(write-bytevector x ($fxadd1 i) j p)))
(define fasl-write-object
(lambda (x p h m)
(cond
[(immediate? x) (fasl-write-immediate x p) m]
[(hashtable-ref h x #f) =>
(lambda (mark)
(unless (fixnum? mark)
(die 'fasl-write "BUG: invalid mark" mark))
(cond
[(fx= mark 0) ; singly referenced
(do-write x p h m)]
[(fx> mark 0) ; marked but not written
(hashtable-set! h x (fx- 0 m))
(put-tag #\> p)
(write-int32 m p)
(do-write x p h (fxadd1 m))]
[else
(put-tag #\< p)
(write-int32 (fx- 0 mark) p)
m]))]
[else (die 'fasl-write "BUG: not in hash table" x)])))
(define make-graph
(lambda (x h)
(unless (immediate? x)
(cond
[(hashtable-ref h x #f) =>
(lambda (i)
(hashtable-set! h x (fxadd1 i)))]
[else
(hashtable-set! h x 0)
(cond
[(pair? x)
(make-graph (car x) h)
(make-graph (cdr x) h)]
[(vector? x)
(let f ([x x] [i 0] [n (vector-length x)])
(unless (fx= i n)
(make-graph (vector-ref x i) h)
(f x (fxadd1 i) n)))]
[(symbol? x)
(make-graph (symbol->string x) h)
(when (gensym? x) (make-graph (gensym->unique-string x) h))]
[(string? x) (void)]
[(code? x)
(make-graph ($code-annotation x) h)
(make-graph (code-reloc-vector x) h)]
[(struct? x)
(when (eq? x (base-rtd))
(die 'fasl-write "base-rtd is not writable"))
(let ([rtd (struct-type-descriptor x)])
(cond
[(eq? rtd (base-rtd))
;;; this is an rtd
(make-graph (struct-type-name x) h)
(make-graph (struct-type-symbol x) h)
(for-each (lambda (x) (make-graph x h))
(struct-type-field-names x))]
[else
;;; this is a record
(make-graph rtd h)
(for-each
(lambda (name)
(make-graph ((struct-field-accessor rtd name) x) h))
(struct-type-field-names rtd))]))]
[(procedure? x)
(let ([code ($closure-code x)])
(unless (fxzero? (code-freevars code))
(die 'fasl-write
"Cannot write a non-thunk procedure; \
the one given has free vars"
(code-freevars code)))
(make-graph code h))]
[(bytevector? x) (void)]
[(flonum? x) (void)]
[(bignum? x) (void)]
[(ratnum? x)
(make-graph (numerator x) h)
(make-graph (denominator x) h)]
[else (die 'fasl-write "not fasl-writable" x)])]))))
(define fasl-write-to-port
(lambda (x port)
(let ([h (make-eq-hashtable)])
(make-graph x h)
(put-tag #\# port)
(put-tag #\@ port)
(put-tag #\I port)
(put-tag #\K port)
(put-tag #\0 port)
(put-tag (if (= wordsize 4) #\1 #\2) port)
(fasl-write-object x port h 1)
(void))))
(define fasl-write
(case-lambda
[(x port)
(unless (and (output-port? port) (binary-port? port))
(die 'fasl-write "not an output port" port))
(fasl-write-to-port x port)])))