src/code/fop.lisp

   1 ;;;; FOP definitions
   2
   3 (in-package "SB!FASL")
   4
   5 ;;; Sometimes we want to skip over any FOPs with side-effects (like
   6 ;;; function calls) while executing other FOPs. *SKIP-UNTIL* will
   7 ;;; either contain the position where the skipping will stop, or
   8 ;;; NIL if we're executing normally.
   9 (defvar *skip-until* nil)
  10
  11 ;;; Define NAME as a fasl operation, with op-code FOP-CODE. PUSHP
  12 ;;; describes what the body does to the fop stack:
  13 ;;;   T
  14 ;;;     The body might pop the fop stack. The result of the body is
  15 ;;;     pushed on the fop stack.
  16 ;;;   NIL
  17 ;;;     The body might pop the fop stack. The result of the body is
  18 ;;;     discarded.
  19 ;;; STACKP describes whether or not the body interacts with the fop stack.
  20 (defmacro define-fop ((name fop-code &key (pushp t) (stackp t)) &rest forms)
  21   `(progn
  22      (defun ,name ()
  23        ,(if stackp
  24             `(with-fop-stack ,pushp ,@forms)
  25             `(progn ,@forms)))
  26      (%define-fop ',name ,fop-code)))
  27
  28 (defun %define-fop (name code)
  29   (let ((oname (svref *fop-names* code)))
  30     (when (and oname (not (eq oname name)))
  31       (error "multiple names for fop code ~D: ~S and ~S" code name oname)))
  32   ;; KLUDGE: It's mnemonically suboptimal to use 'FOP-CODE as the name of the
  33   ;; tag which associates names with codes when it's also used as one of
  34   ;; the names. Perhaps the fops named FOP-CODE and FOP-SMALL-CODE could
  35   ;; be renamed to something more mnemonic? -- WHN 19990902
  36   (let ((ocode (get name 'fop-code)))
  37     (when (and ocode (/= ocode code))
  38       (error "multiple codes for fop name ~S: ~D and ~D" name code ocode)))
  39   (setf (svref *fop-names* code) name
  40         (get name 'fop-code) code
  41         (svref *fop-funs* code) (symbol-function name))
  42   (values))
  43
  44 ;;; Define a pair of fops which are identical except that one reads
  45 ;;; a four-byte argument while the other reads a one-byte argument. The
  46 ;;; argument can be accessed by using the CLONE-ARG macro.
  47 ;;;
  48 ;;; KLUDGE: It would be nice if the definition here encapsulated which
  49 ;;; value ranges went with which fop variant, and chose the correct
  50 ;;; fop code to use. Currently, since such logic isn't encapsulated,
  51 ;;; we see callers doing stuff like
  52 ;;;     (cond ((and (< num-consts #x100) (< total-length #x10000))
  53 ;;;            (dump-fop 'sb!impl::fop-small-code file)
  54 ;;;            (dump-byte num-consts file)
  55 ;;;            (dump-integer-as-n-bytes total-length 2 file))
  56 ;;;           (t
  57 ;;;            (dump-fop 'sb!impl::fop-code file)
  58 ;;;            (dump-word num-consts file)
  59 ;;;            (dump-word total-length file))))
  60 ;;; in several places. It would be cleaner if this could be replaced with
  61 ;;; something like
  62 ;;;     (dump-fop file fop-code num-consts total-length)
  63 ;;; Some of this logic is already in DUMP-FOP*, but that still requires the
  64 ;;; caller to know that it's a 1-byte-arg/4-byte-arg cloned fop pair, and to
  65 ;;; know both the 1-byte-arg and the 4-byte-arg fop names. -- WHN 19990902
  66 (defmacro define-cloned-fops ((name code &key (pushp t) (stackp t))
  67                               (small-name small-code) &rest forms)
  68   (aver (member pushp '(nil t)))
  69   (aver (member stackp '(nil t)))
  70   `(progn
  71      (macrolet ((clone-arg () '(read-word-arg)))
  72        (define-fop (,name ,code :pushp ,pushp :stackp ,stackp) ,@forms))
  73      (macrolet ((clone-arg () '(read-byte-arg)))
  74        (define-fop (,small-name ,small-code :pushp ,pushp :stackp ,stackp) ,@forms))))
  75
  76 ;;; a helper function for reading string values from FASL files: sort
  77 ;;; of like READ-SEQUENCE specialized for files of (UNSIGNED-BYTE 8),
  78 ;;; with an automatic conversion from (UNSIGNED-BYTE 8) into CHARACTER
  79 ;;; for each element read
  80 (declaim (ftype (function (stream simple-string &optional index) (values))
  81                 read-string-as-bytes
  82                 #!+sb-unicode read-string-as-unsigned-byte-32))
  83 (defun read-string-as-bytes (stream string &optional (length (length string)))
  84   (dotimes (i length)
  85     (setf (aref string i)
  86           (sb!xc:code-char (read-byte stream))))
  87   ;; FIXME: The classic CMU CL code to do this was
  88   ;;   (READ-N-BYTES FILE STRING START END).
  89   ;; It was changed for SBCL because we needed a portable version for
  90   ;; bootstrapping. Benchmark the non-portable version and see whether it's
  91   ;; significantly better than the portable version here. If it is, then use
  92   ;; it as an alternate definition, protected with #-SB-XC-HOST.
  93   (values))
  94 #!+sb-unicode
  95 (defun read-string-as-unsigned-byte-32
  96     (stream string &optional (length (length string)))
  97   #+sb-xc-host (bug "READ-STRING-AS-UNSIGNED-BYTE-32 called")
  98   (dotimes (i length)
  99     (setf (aref string i)
 100           (let ((code 0))
 101             (dotimes (k 4 (sb!xc:code-char code))
 102               (setf code (logior code (ash (read-byte stream)
 103                                            (* k sb!vm:n-byte-bits))))))))
 104   (values))
 105 \f
 106 ;;;; miscellaneous fops
 107
 108 ;;; FIXME: POP-STACK should be called something more mnemonic. (POP-FOP-STACK?
 109 ;;; But that would conflict with PUSH-FOP-TABLE. Something, anyway..)
 110
 111 ;;; Setting this variable causes execution of a FOP-NOP4 to produce
 112 ;;; output to *DEBUG-IO*. This can be handy when trying to follow the
 113 ;;; progress of FASL loading.
 114 #!+sb-show
 115 (defvar *show-fop-nop4-p* nil)
 116
 117 ;;; CMU CL had a single no-op fop, FOP-NOP, with fop code 0. Since 0
 118 ;;; occurs disproportionately often in fasl files for other reasons,
 119 ;;; FOP-NOP is less than ideal for writing human-readable patterns
 120 ;;; into fasl files for debugging purposes. There's no shortage of
 121 ;;; unused fop codes, so we add this second NOP, which reads 4
 122 ;;; arbitrary bytes and discards them.
 123 (define-fop (fop-nop4 137 :stackp nil)
 124   (let ((arg (read-arg 4)))
 125     (declare (ignorable arg))
 126     #!+sb-show
 127     (when *show-fop-nop4-p*
 128       (format *debug-io* "~&/FOP-NOP4 ARG=~W=#X~X~%" arg arg))))
 129
 130 (define-fop (fop-nop 0 :stackp nil))
 131 (define-fop (fop-pop 1 :pushp nil) (push-fop-table (pop-stack)))
 132 (define-fop (fop-push 2) (svref *current-fop-table* (read-word-arg)))
 133 (define-fop (fop-byte-push 3) (svref *current-fop-table* (read-byte-arg)))
 134
 135 (define-fop (fop-empty-list 4) ())
 136 (define-fop (fop-truth 5) t)
 137 ;;; CMU CL had FOP-POP-FOR-EFFECT as fop 65, but it was never used and seemed
 138 ;;; to have no possible use.
 139 (define-fop (fop-misc-trap 66)
 140   #+sb-xc-host ; since xc host doesn't know how to compile %PRIMITIVE
 141   (error "FOP-MISC-TRAP can't be defined without %PRIMITIVE.")
 142   #-sb-xc-host
 143   (%primitive sb!c:make-other-immediate-type 0 sb!vm:unbound-marker-widetag))
 144
 145 (define-cloned-fops (fop-character 68) (fop-short-character 69)
 146   (code-char (clone-arg)))
 147
 148 (define-cloned-fops (fop-struct 48) (fop-small-struct 49)
 149   (let* ((size (clone-arg))
 150          (res (%make-instance size)))
 151     (declare (type index size))
 152     (let* ((layout (pop-stack))
 153            (nuntagged (layout-n-untagged-slots layout))
 154            (ntagged (- size nuntagged)))
 155       (setf (%instance-ref res 0) layout)
 156       (dotimes (n (1- ntagged))
 157         (declare (type index n))
 158         (setf (%instance-ref res (1+ n)) (pop-stack)))
 159       (dotimes (n nuntagged)
 160         (declare (type index n))
 161         (setf (%raw-instance-ref/word res (- nuntagged n 1)) (pop-stack))))
 162     res))
 163
 164 (define-fop (fop-layout 45)
 165   (let ((nuntagged (pop-stack))
 166         (length (pop-stack))
 167         (depthoid (pop-stack))
 168         (inherits (pop-stack))
 169         (name (pop-stack)))
 170     (find-and-init-or-check-layout name length inherits depthoid nuntagged)))
 171
 172 (define-fop (fop-end-group 64 :stackp nil)
 173   (/show0 "THROWing FASL-GROUP-END")
 174   (throw 'fasl-group-end t))
 175
 176 ;;; In the normal loader, we just ignore these. GENESIS overwrites
 177 ;;; FOP-MAYBE-COLD-LOAD with something that knows whether to revert to
 178 ;;; cold-loading or not.
 179 (define-fop (fop-normal-load 81 :stackp nil))
 180 (define-fop (fop-maybe-cold-load 82 :stackp nil))
 181
 182 (define-fop (fop-verify-table-size 62 :stackp nil)
 183   (let ((expected-index (read-word-arg)))
 184     (unless (= *current-fop-table-index* expected-index)
 185       (bug "fasl table of improper size"))))
 186 (define-fop (fop-verify-empty-stack 63 :stackp nil)
 187   (unless (zerop (length *fop-stack*))
 188     (bug "fasl stack not empty when it should be")))
 189 \f
 190 ;;;; fops for loading symbols
 191
 192 (macrolet (;; FIXME: Should all this code really be duplicated inside
 193            ;; each fop? Perhaps it would be better for this shared
 194            ;; code to live in FLET FROB1 and FLET FROB4 (for the
 195            ;; two different sizes of counts).
 196            (frob (name code name-size package)
 197              (let ((n-package (gensym))
 198                    (n-size (gensym))
 199                    (n-buffer (gensym)))
 200                `(define-fop (,name ,code)
 201                   (prepare-for-fast-read-byte *fasl-input-stream*
 202                     (let ((,n-package ,package)
 203                           (,n-size (fast-read-u-integer ,name-size)))
 204                       (when (> ,n-size (length *fasl-symbol-buffer*))
 205                         (setq *fasl-symbol-buffer*
 206                               (make-string (* ,n-size 2))))
 207                       (done-with-fast-read-byte)
 208                       (let ((,n-buffer *fasl-symbol-buffer*))
 209                         #+sb-xc-host
 210                         (read-string-as-bytes *fasl-input-stream*
 211                                               ,n-buffer
 212                                               ,n-size)
 213                         #-sb-xc-host
 214                         (#!+sb-unicode read-string-as-unsigned-byte-32
 215                          #!-sb-unicode read-string-as-bytes
 216                          *fasl-input-stream*
 217                          ,n-buffer
 218                          ,n-size)
 219                         (push-fop-table (without-package-locks
 220                                          (intern* ,n-buffer
 221                                                   ,n-size
 222                                                   ,n-package))))))))))
 223
 224   ;; Note: CMU CL had FOP-SYMBOL-SAVE and FOP-SMALL-SYMBOL-SAVE, but
 225   ;; since they made the behavior of the fasloader depend on the
 226   ;; *PACKAGE* variable, not only were they a pain to support (because
 227   ;; they required various hacks to handle *PACKAGE*-manipulation
 228   ;; forms) they were basically broken by design, because ANSI gives
 229   ;; the user so much flexibility in manipulating *PACKAGE* at
 230   ;; load-time that no reasonable hacks could possibly make things
 231   ;; work right. The ones used in CMU CL certainly didn't, as shown by
 232   ;; e.g.
 233   ;;   (IN-PACKAGE :CL-USER)
 234   ;;     (DEFVAR CL::*FOO* 'FOO-VALUE)
 235   ;;     (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
 236   ;;       (SETF *PACKAGE* (FIND-PACKAGE :CL)))
 237   ;; which in CMU CL 2.4.9 defines a variable CL-USER::*FOO* instead of
 238   ;; defining CL::*FOO*. Therefore, we don't use those fops in SBCL.
 239   ;;(frob fop-symbol-save               6 4 *package*)
 240   ;;(frob fop-small-symbol-save   7 1 *package*)
 241
 242   (frob fop-lisp-symbol-save          75 #.sb!vm:n-word-bytes *cl-package*)
 243   (frob fop-lisp-small-symbol-save    76 1 *cl-package*)
 244   (frob fop-keyword-symbol-save       77 #.sb!vm:n-word-bytes *keyword-package*)
 245   (frob fop-keyword-small-symbol-save 78 1 *keyword-package*)
 246
 247   ;; FIXME: Because we don't have FOP-SYMBOL-SAVE any more, an enormous number
 248   ;; of symbols will fall through to this case, probably resulting in bloated
 249   ;; fasl files. A new
 250   ;; FOP-SYMBOL-IN-LAST-PACKAGE-SAVE/FOP-SMALL-SYMBOL-IN-LAST-PACKAGE-SAVE
 251   ;; cloned fop pair could undo some of this bloat.
 252   (frob fop-symbol-in-package-save 8 #.sb!vm:n-word-bytes
 253     (svref *current-fop-table* (fast-read-u-integer #.sb!vm:n-word-bytes)))
 254   (frob fop-small-symbol-in-package-save 9 1
 255     (svref *current-fop-table* (fast-read-u-integer #.sb!vm:n-word-bytes)))
 256   (frob fop-symbol-in-byte-package-save 10 #.sb!vm:n-word-bytes
 257     (svref *current-fop-table* (fast-read-u-integer 1)))
 258   (frob fop-small-symbol-in-byte-package-save 11 1
 259     (svref *current-fop-table* (fast-read-u-integer 1))))
 260
 261 (define-cloned-fops (fop-uninterned-symbol-save 12)
 262                     (fop-uninterned-small-symbol-save 13)
 263   (let* ((arg (clone-arg))
 264          (res (make-string arg)))
 265     #!-sb-unicode
 266     (read-string-as-bytes *fasl-input-stream* res)
 267     #!+sb-unicode
 268     (read-string-as-unsigned-byte-32 *fasl-input-stream* res)
 269     (push-fop-table (make-symbol res))))
 270
 271 (define-fop (fop-package 14)
 272   (find-undeleted-package-or-lose (pop-stack)))
 273 \f
 274 ;;;; fops for loading numbers
 275
 276 ;;; Load a signed integer LENGTH bytes long from *FASL-INPUT-STREAM*.
 277 (defun load-s-integer (length)
 278   (declare (fixnum length))
 279   ;; #+cmu (declare (optimize (inhibit-warnings 2)))
 280   (do* ((index length (1- index))
 281         (byte 0 (read-byte *fasl-input-stream*))
 282         (result 0 (+ result (ash byte bits)))
 283         (bits 0 (+ bits 8)))
 284        ((= index 0)
 285         (if (logbitp 7 byte)    ; look at sign bit
 286             (- result (ash 1 bits))
 287             result))
 288     (declare (fixnum index byte bits))))
 289
 290 (define-cloned-fops (fop-integer 33) (fop-small-integer 34)
 291   (load-s-integer (clone-arg)))
 292
 293 (define-fop (fop-word-integer 35)
 294   (prepare-for-fast-read-byte *fasl-input-stream*
 295     (prog1
 296      (fast-read-s-integer #.sb!vm:n-word-bytes)
 297      (done-with-fast-read-byte))))
 298
 299 (define-fop (fop-byte-integer 36)
 300   (prepare-for-fast-read-byte *fasl-input-stream*
 301     (prog1
 302      (fast-read-s-integer 1)
 303      (done-with-fast-read-byte))))
 304
 305 (define-fop (fop-ratio 70)
 306   (let ((den (pop-stack)))
 307     (%make-ratio (pop-stack) den)))
 308
 309 (define-fop (fop-complex 71)
 310   (let ((im (pop-stack)))
 311     (%make-complex (pop-stack) im)))
 312
 313 (macrolet ((fast-read-single-float ()
 314              '(make-single-float (fast-read-s-integer 4)))
 315            (fast-read-double-float ()
 316              '(let ((lo (fast-read-u-integer 4)))
 317                (make-double-float (fast-read-s-integer 4) lo))))
 318   (macrolet ((define-complex-fop (name fop-code type)
 319                (let ((reader (symbolicate "FAST-READ-" type)))
 320                  `(define-fop (,name ,fop-code)
 321                       (prepare-for-fast-read-byte *fasl-input-stream*
 322                         (prog1
 323                             (complex (,reader) (,reader))
 324                           (done-with-fast-read-byte))))))
 325              (define-float-fop (name fop-code type)
 326                (let ((reader (symbolicate "FAST-READ-" type)))
 327                  `(define-fop (,name ,fop-code)
 328                       (prepare-for-fast-read-byte *fasl-input-stream*
 329                         (prog1
 330                             (,reader)
 331                           (done-with-fast-read-byte)))))))
 332     (define-complex-fop fop-complex-single-float 72 single-float)
 333     (define-complex-fop fop-complex-double-float 73 double-float)
 334     #!+long-float
 335     (define-complex-fop fop-complex-long-float 67 long-float)
 336     (define-float-fop fop-single-float 46 single-float)
 337     (define-float-fop fop-double-float 47 double-float)
 338     #!+long-float
 339     (define-float-fop fop-long-float 52 long-float)))
 340
 341 \f
 342 ;;;; loading lists
 343
 344 (define-fop (fop-list 15)
 345   (do ((res () (cons (pop-stack) res))
 346        (n (read-byte-arg) (1- n)))
 347       ((zerop n) res)
 348     (declare (type index n))))
 349
 350 (define-fop (fop-list* 16)
 351   (do ((res (pop-stack) (cons (pop-stack) res))
 352        (n (read-byte-arg) (1- n)))
 353       ((zerop n) res)
 354     (declare (type index n))))
 355
 356 (macrolet ((frob (name op fun n)
 357              `(define-fop (,name ,op)
 358                 (call-with-popped-args ,fun ,n))))
 359
 360   (frob fop-list-1 17 list 1)
 361   (frob fop-list-2 18 list 2)
 362   (frob fop-list-3 19 list 3)
 363   (frob fop-list-4 20 list 4)
 364   (frob fop-list-5 21 list 5)
 365   (frob fop-list-6 22 list 6)
 366   (frob fop-list-7 23 list 7)
 367   (frob fop-list-8 24 list 8)
 368
 369   (frob fop-list*-1 25 list* 2)
 370   (frob fop-list*-2 26 list* 3)
 371   (frob fop-list*-3 27 list* 4)
 372   (frob fop-list*-4 28 list* 5)
 373   (frob fop-list*-5 29 list* 6)
 374   (frob fop-list*-6 30 list* 7)
 375   (frob fop-list*-7 31 list* 8)
 376   (frob fop-list*-8 32 list* 9))
 377 \f
 378 ;;;; fops for loading arrays
 379
 380 (define-cloned-fops (fop-base-string 37) (fop-small-base-string 38)
 381   (let* ((arg (clone-arg))
 382          (res (make-string arg :element-type 'base-char)))
 383     (read-string-as-bytes *fasl-input-stream* res)
 384     res))
 385
 386 #!+sb-unicode
 387 (progn
 388   #+sb-xc-host
 389   (define-cloned-fops (fop-character-string 161) (fop-small-character-string 162)
 390     (bug "CHARACTER-STRING FOP encountered"))
 391
 392   #-sb-xc-host
 393   (define-cloned-fops (fop-character-string 161) (fop-small-character-string 162)
 394     (let* ((arg (clone-arg))
 395            (res (make-string arg)))
 396       (read-string-as-unsigned-byte-32 *fasl-input-stream* res)
 397       res)))
 398
 399 (define-cloned-fops (fop-vector 39) (fop-small-vector 40)
 400   (let* ((size (clone-arg))
 401          (res (make-array size)))
 402     (declare (fixnum size))
 403     (do ((n (1- size) (1- n)))
 404         ((minusp n))
 405       (setf (svref res n) (pop-stack)))
 406     res))
 407
 408 (define-fop (fop-array 83)
 409   (let* ((rank (read-word-arg))
 410          (vec (pop-stack))
 411          (length (length vec))
 412          (res (make-array-header sb!vm:simple-array-widetag rank)))
 413     (declare (simple-array vec)
 414              (type (unsigned-byte #.(- sb!vm:n-word-bits sb!vm:n-widetag-bits)) rank))
 415     (set-array-header res vec length nil 0
 416                       (do ((i rank (1- i))
 417                            (dimensions () (cons (pop-stack) dimensions)))
 418                           ((zerop i) dimensions)
 419                         (declare (type index i)))
 420                       nil)
 421     res))
 422
 423 (define-fop (fop-single-float-vector 84)
 424   (let* ((length (read-word-arg))
 425          (result (make-array length :element-type 'single-float)))
 426     (read-n-bytes *fasl-input-stream* result 0 (* length 4))
 427     result))
 428
 429 (define-fop (fop-double-float-vector 85)
 430   (let* ((length (read-word-arg))
 431          (result (make-array length :element-type 'double-float)))
 432     (read-n-bytes *fasl-input-stream* result 0 (* length 8))
 433     result))
 434
 435 (define-fop (fop-complex-single-float-vector 86)
 436   (let* ((length (read-word-arg))
 437          (result (make-array length :element-type '(complex single-float))))
 438     (read-n-bytes *fasl-input-stream* result 0 (* length 8))
 439     result))
 440
 441 (define-fop (fop-complex-double-float-vector 87)
 442   (let* ((length (read-word-arg))
 443          (result (make-array length :element-type '(complex double-float))))
 444     (read-n-bytes *fasl-input-stream* result 0 (* length 16))
 445     result))
 446
 447 ;;; CMU CL comment:
 448 ;;;   *** NOT *** the FOP-INT-VECTOR as currently documented in rtguts.
 449 ;;;   Size must be a directly supported I-vector element size, with no
 450 ;;;   extra bits. This must be packed according to the local
 451 ;;;   byte-ordering, allowing us to directly read the bits.
 452 (define-fop (fop-int-vector 43)
 453   (prepare-for-fast-read-byte *fasl-input-stream*
 454     (let* ((len (fast-read-u-integer #.sb!vm:n-word-bytes))
 455            (size (fast-read-byte))
 456            (res (case size
 457                   (0 (make-array len :element-type 'nil))
 458                   (1 (make-array len :element-type 'bit))
 459                   (2 (make-array len :element-type '(unsigned-byte 2)))
 460                   (4 (make-array len :element-type '(unsigned-byte 4)))
 461                   (7 (prog1 (make-array len :element-type '(unsigned-byte 7))
 462                        (setf size 8)))
 463                   (8 (make-array len :element-type '(unsigned-byte 8)))
 464                   (15 (prog1 (make-array len :element-type '(unsigned-byte 15))
 465                         (setf size 16)))
 466                   (16 (make-array len :element-type '(unsigned-byte 16)))
 467                   (31 (prog1 (make-array len :element-type '(unsigned-byte 31))
 468                         (setf size 32)))
 469                   (32 (make-array len :element-type '(unsigned-byte 32)))
 470                   #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
 471                   (63 (prog1 (make-array len :element-type '(unsigned-byte 63))
 472                         (setf size 64)))
 473                   (64 (make-array len :element-type '(unsigned-byte 64)))
 474                   (t (bug "losing i-vector element size: ~S" size)))))
 475       (declare (type index len))
 476       (done-with-fast-read-byte)
 477       (read-n-bytes *fasl-input-stream*
 478                     res
 479                     0
 480                     (ceiling (the index (* size len)) sb!vm:n-byte-bits))
 481       res)))
 482
 483 ;;; This is the same as FOP-INT-VECTOR, except this is for signed
 484 ;;; SIMPLE-ARRAYs.
 485 (define-fop (fop-signed-int-vector 50)
 486   (prepare-for-fast-read-byte *fasl-input-stream*
 487     (let* ((len (fast-read-u-integer #.sb!vm:n-word-bytes))
 488            (size (fast-read-byte))
 489            (res (case size
 490                   (8 (make-array len :element-type '(signed-byte 8)))
 491                   (16 (make-array len :element-type '(signed-byte 16)))
 492                   #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
 493                   (29 (prog1 (make-array len :element-type '(unsigned-byte 29))
 494                         (setf size 32)))
 495                   #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
 496                   (30 (prog1 (make-array len :element-type '(signed-byte 30))
 497                         (setf size 32)))
 498                   (32 (make-array len :element-type '(signed-byte 32)))
 499                   #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
 500                   (60 (prog1 (make-array len :element-type '(unsigned-byte 60))
 501                         (setf size 64)))
 502                   #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
 503                   (61 (prog1 (make-array len :element-type '(signed-byte 61))
 504                         (setf size 64)))
 505                   #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
 506                   (64 (make-array len :element-type '(signed-byte 64)))
 507                   (t (bug "losing si-vector element size: ~S" size)))))
 508       (declare (type index len))
 509       (done-with-fast-read-byte)
 510       (read-n-bytes *fasl-input-stream*
 511                     res
 512                     0
 513                     (ceiling (the index (* size len)) sb!vm:n-byte-bits))
 514       res)))
 515
 516 (define-fop (fop-eval 53)
 517   (if *skip-until*
 518       (pop-stack)
 519       (let ((result (eval (pop-stack))))
 520         ;; FIXME: CMU CL had this code here:
 521         ;;   (when *load-print*
 522         ;;     (load-fresh-line)
 523         ;;     (prin1 result)
 524         ;;     (terpri))
 525         ;; Unfortunately, this dependence on the *LOAD-PRINT* global
 526         ;; variable is non-ANSI, so for now we've just punted printing in
 527         ;; fasl loading.
 528         result)))
 529
 530 (define-fop (fop-eval-for-effect 54 :pushp nil)
 531   (if *skip-until*
 532       (pop-stack)
 533       (let ((result (eval (pop-stack))))
 534         ;; FIXME: See the comment about *LOAD-PRINT* in FOP-EVAL.
 535         (declare (ignore result))
 536         #+nil (when *load-print*
 537                 (load-fresh-line)
 538                 (prin1 result)
 539                 (terpri)))))
 540
 541 (define-fop (fop-funcall 55)
 542   (let ((arg (read-byte-arg)))
 543     (if *skip-until*
 544         (dotimes (i (1+ arg))
 545           (pop-stack))
 546         (if (zerop arg)
 547             (funcall (pop-stack))
 548             (do ((args () (cons (pop-stack) args))
 549                  (n arg (1- n)))
 550                 ((zerop n) (apply (pop-stack) args))
 551               (declare (type index n)))))))
 552
 553 (define-fop (fop-funcall-for-effect 56 :pushp nil)
 554   (let ((arg (read-byte-arg)))
 555     (if *skip-until*
 556         (dotimes (i (1+ arg))
 557           (pop-stack))
 558         (if (zerop arg)
 559             (funcall (pop-stack))
 560             (do ((args () (cons (pop-stack) args))
 561                  (n arg (1- n)))
 562                 ((zerop n) (apply (pop-stack) args))
 563               (declare (type index n)))))))
 564 \f
 565 ;;;; fops for fixing up circularities
 566
 567 (define-fop (fop-rplaca 200 :pushp nil)
 568   (let ((obj (svref *current-fop-table* (read-word-arg)))
 569         (idx (read-word-arg))
 570         (val (pop-stack)))
 571     (setf (car (nthcdr idx obj)) val)))
 572
 573 (define-fop (fop-rplacd 201 :pushp nil)
 574   (let ((obj (svref *current-fop-table* (read-word-arg)))
 575         (idx (read-word-arg))
 576         (val (pop-stack)))
 577     (setf (cdr (nthcdr idx obj)) val)))
 578
 579 (define-fop (fop-svset 202 :pushp nil)
 580   (let* ((obi (read-word-arg))
 581          (obj (svref *current-fop-table* obi))
 582          (idx (read-word-arg))
 583          (val (pop-stack)))
 584     (if (%instancep obj)
 585         (setf (%instance-ref obj idx) val)
 586         (setf (svref obj idx) val))))
 587
 588 (define-fop (fop-structset 204 :pushp nil)
 589   (setf (%instance-ref (svref *current-fop-table* (read-word-arg))
 590                        (read-word-arg))
 591         (pop-stack)))
 592
 593 ;;; In the original CMUCL code, this actually explicitly declared PUSHP
 594 ;;; to be T, even though that's what it defaults to in DEFINE-FOP.
 595 (define-fop (fop-nthcdr 203)
 596   (nthcdr (read-word-arg) (pop-stack)))
 597 \f
 598 ;;;; fops for loading functions
 599
 600 ;;; (In CMU CL there was a FOP-CODE-FORMAT (47) which was
 601 ;;; conventionally placed at the beginning of each fasl file to test
 602 ;;; for compatibility between the fasl file and the CMU CL which
 603 ;;; loaded it. In SBCL, this functionality has been replaced by
 604 ;;; putting the implementation and version in required fields in the
 605 ;;; fasl file header.)
 606
 607 (define-fop (fop-code 58 :stackp nil)
 608   (load-code (read-word-arg) (read-word-arg)))
 609
 610 (define-fop (fop-small-code 59 :stackp nil)
 611   (load-code (read-byte-arg) (read-halfword-arg)))
 612
 613 (define-fop (fop-fdefinition 60)
 614   (fdefinition-object (pop-stack) t))
 615
 616 (define-fop (fop-sanctify-for-execution 61)
 617   (let ((component (pop-stack)))
 618     (sb!vm:sanctify-for-execution component)
 619     component))
 620
 621 (define-fop (fop-fset 74 :pushp nil)
 622   ;; Ordinary, not-for-cold-load code shouldn't need to mess with this
 623   ;; at all, since it's only used as part of the conspiracy between
 624   ;; the cross-compiler and GENESIS to statically link FDEFINITIONs
 625   ;; for cold init.
 626   (warn "~@<FOP-FSET seen in ordinary load (not cold load) -- quite strange! ~
 627 If you didn't do something strange to cause this, please report it as a ~
 628 bug.~:@>")
 629   ;; Unlike CMU CL, we don't treat this as a no-op in ordinary code.
 630   ;; If the user (or, more likely, developer) is trying to reload
 631   ;; compiled-for-cold-load code into a warm SBCL, we'll do a warm
 632   ;; assignment. (This is partly for abstract tidiness, since the warm
 633   ;; assignment is the closest analogy to what happens at cold load,
 634   ;; and partly because otherwise our compiled-for-cold-load code will
 635   ;; fail, since in SBCL things like compiled-for-cold-load %DEFUN
 636   ;; depend more strongly than in CMU CL on FOP-FSET actually doing
 637   ;; something.)
 638   (let ((fn (pop-stack))
 639         (name (pop-stack)))
 640     (setf (fdefinition name) fn)))
 641
 642 ;;; Modify a slot in a CONSTANTS object.
 643 (define-cloned-fops (fop-alter-code 140 :pushp nil) (fop-byte-alter-code 141)
 644   (let ((value (pop-stack))
 645         (code (pop-stack)))
 646     (setf (code-header-ref code (clone-arg)) value)
 647     (values)))
 648
 649 (define-fop (fop-fun-entry 142)
 650   #+sb-xc-host ; since xc host doesn't know how to compile %PRIMITIVE
 651   (error "FOP-FUN-ENTRY can't be defined without %PRIMITIVE.")
 652   #-sb-xc-host
 653   (let ((xrefs (pop-stack))
 654         (type (pop-stack))
 655         (arglist (pop-stack))
 656         (name (pop-stack))
 657         (code-object (pop-stack))
 658         (offset (read-word-arg)))
 659     (declare (type index offset))
 660     (unless (zerop (logand offset sb!vm:lowtag-mask))
 661       (bug "unaligned function object, offset = #X~X" offset))
 662     (let ((fun (%primitive sb!c:compute-fun code-object offset)))
 663       (setf (%simple-fun-self fun) fun)
 664       (setf (%simple-fun-next fun) (%code-entry-points code-object))
 665       (setf (%code-entry-points code-object) fun)
 666       (setf (%simple-fun-name fun) name)
 667       (setf (%simple-fun-arglist fun) arglist)
 668       (setf (%simple-fun-type fun) type)
 669       (setf (%simple-fun-xrefs fun) xrefs)
 670       ;; FIXME: See the comment about *LOAD-PRINT* in FOP-EVAL.
 671       #+nil (when *load-print*
 672               (load-fresh-line)
 673               (format t "~S defined~%" fun))
 674       fun)))
 675 \f
 676 ;;;; Some Dylan FOPs used to live here. By 1 November 1998 the code
 677 ;;;; was sufficiently stale that the functions it called were no
 678 ;;;; longer defined, so I (William Harold Newman) deleted it.
 679 ;;;;
 680 ;;;; In case someone in the future is trying to make sense of FOP layout,
 681 ;;;; it might be worth recording that the Dylan FOPs were
 682 ;;;;    100 FOP-DYLAN-SYMBOL-SAVE
 683 ;;;;    101 FOP-SMALL-DYLAN-SYMBOL-SAVE
 684 ;;;;    102 FOP-DYLAN-KEYWORD-SAVE
 685 ;;;;    103 FOP-SMALL-DYLAN-KEYWORD-SAVE
 686 ;;;;    104 FOP-DYLAN-VARINFO-VALUE
 687 \f
 688 ;;;; assemblerish fops
 689
 690 (define-fop (fop-assembler-code 144)
 691   (error "cannot load assembler code except at cold load"))
 692
 693 (define-fop (fop-assembler-routine 145)
 694   (error "cannot load assembler code except at cold load"))
 695
 696 (define-fop (fop-foreign-fixup 147)
 697   (let* ((kind (pop-stack))
 698          (code-object (pop-stack))
 699          (len (read-byte-arg))
 700          (sym (make-string len :element-type 'base-char)))
 701     (read-n-bytes *fasl-input-stream* sym 0 len)
 702     (sb!vm:fixup-code-object code-object
 703                              (read-word-arg)
 704                              (foreign-symbol-address sym)
 705                              kind)
 706     code-object))
 707
 708 (define-fop (fop-assembler-fixup 148)
 709   (let ((routine (pop-stack))
 710         (kind (pop-stack))
 711         (code-object (pop-stack)))
 712     (multiple-value-bind (value found) (gethash routine *assembler-routines*)
 713       (unless found
 714         (error "undefined assembler routine: ~S" routine))
 715       (sb!vm:fixup-code-object code-object (read-word-arg) value kind))
 716     code-object))
 717
 718 (define-fop (fop-code-object-fixup 149)
 719   (let ((kind (pop-stack))
 720         (code-object (pop-stack)))
 721     ;; Note: We don't have to worry about GC moving the code-object after
 722     ;; the GET-LISP-OBJ-ADDRESS and before that value is deposited, because
 723     ;; we can only use code-object fixups when code-objects don't move.
 724     (sb!vm:fixup-code-object code-object (read-word-arg)
 725                              (get-lisp-obj-address code-object) kind)
 726     code-object))
 727
 728 #!+linkage-table
 729 (define-fop (fop-foreign-dataref-fixup 150)
 730   (let* ((kind (pop-stack))
 731          (code-object (pop-stack))
 732          (len (read-byte-arg))
 733          (sym (make-string len :element-type 'base-char)))
 734     (read-n-bytes *fasl-input-stream* sym 0 len)
 735     (sb!vm:fixup-code-object code-object
 736                              (read-word-arg)
 737                              (foreign-symbol-address sym t)
 738                              kind)
 739     code-object))
 740
 741 ;;; FOPs needed for implementing an IF operator in a FASL
 742
 743 ;;; Skip until a FOP-MAYBE-STOP-SKIPPING with the same POSITION is
 744 ;;; executed. While skipping, we execute most FOPs normally, except
 745 ;;; for ones that a) funcall/eval b) start skipping. This needs to
 746 ;;; be done to ensure that the fop table gets populated correctly
 747 ;;; regardless of the execution path.
 748 (define-fop (fop-skip 151 :pushp nil)
 749   (let ((position (pop-stack)))
 750     (unless *skip-until*
 751       (setf *skip-until* position)))
 752   (values))
 753
 754 ;;; As before, but only start skipping if the top of the FOP stack is NIL.
 755 (define-fop (fop-skip-if-false 152 :pushp nil)
 756   (let ((condition (pop-stack))
 757         (position (pop-stack)))
 758     (unless (or condition
 759                 *skip-until*)
 760       (setf *skip-until* position)))
 761   (values))
 762
 763 ;;; If skipping, pop the top of the stack and discard it. Needed for
 764 ;;; ensuring that the stack stays balanced when skipping.
 765 (define-fop (fop-drop-if-skipping 153 :pushp nil)
 766   (when *skip-until*
 767     (pop-stack))
 768   (values))
 769
 770 ;;; If skipping, push a dummy value on the stack. Needed for
 771 ;;; ensuring that the stack stays balanced when skipping.
 772 (define-fop (fop-push-nil-if-skipping 154 :pushp nil)
 773   (when *skip-until*
 774     (push-stack nil))
 775   (values))
 776
 777 ;;; Stop skipping if the top of the stack matches *SKIP-UNTIL*
 778 (define-fop (fop-maybe-stop-skipping 155 :pushp nil)
 779   (let ((label (pop-stack)))
 780     (when (eql *skip-until* label)
 781       (setf *skip-until* nil)))
 782   (values))