1 ;;;; stuff that creates debugger information from the compiler's
2 ;;;; internal data structures
4 ;;;; This software is part of the SBCL system. See the README file for
7 ;;;; This software is derived from the CMU CL system, which was
8 ;;;; written at Carnegie Mellon University and released into the
9 ;;;; public domain. The software is in the public domain and is
10 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
11 ;;;; files for more information.
15 (deftype byte-buffer
() '(vector (unsigned-byte 8)))
16 (defvar *byte-buffer
*)
17 (declaim (type byte-buffer
*byte-buffer
*))
21 (deftype location-kind
()
22 '(member :unknown-return
:known-return
:internal-error
:non-local-exit
23 :block-start
:call-site
:single-value-return
:non-local-entry
26 ;;; The LOCATION-INFO structure holds the information what we need
27 ;;; about locations which code generation decided were "interesting".
28 (defstruct (location-info
29 (:constructor make-location-info
(kind label vop
))
31 ;; The kind of location noted.
32 (kind nil
:type location-kind
)
33 ;; The label pointing to the interesting code location.
34 (label nil
:type
(or label index null
))
35 ;; The VOP that emitted this location (for node, save-set, ir2-block, etc.)
38 ;;; This is called during code generation in places where there is an
39 ;;; "interesting" location: someplace where we are likely to end up
40 ;;; in the debugger, and thus want debug info.
41 (defun note-debug-location (vop label kind
)
42 (declare (type vop vop
) (type (or label null
) label
)
43 (type location-kind kind
))
44 (let ((location (make-location-info kind label vop
)))
45 (setf (ir2-block-locations (vop-block vop
))
46 (nconc (ir2-block-locations (vop-block vop
))
50 #!-sb-fluid
(declaim (inline ir2-block-physenv
))
51 (defun ir2-block-physenv (2block)
52 (declare (type ir2-block
2block
))
53 (block-physenv (ir2-block-block 2block
)))
55 (defun make-lexenv-var-cache (lexenv)
56 (or (lexenv-var-cache lexenv
)
57 (let ((cache (make-hash-table :test
#'eq
)))
58 (labels ((populate (lexenv)
59 (loop for
(nil . var
) in
(lexenv-vars lexenv
)
60 when
(lambda-var-p var
)
61 do
(setf (gethash var cache
) t
))
62 (let* ((lambda (lexenv-lambda lexenv
))
63 (call-lexenv (and lambda
64 (lambda-call-lexenv lambda
))))
65 (cond ((not call-lexenv
))
66 ((lexenv-var-cache call-lexenv
)
67 (loop for var being each hash-key of
(lexenv-var-cache call-lexenv
)
68 do
(setf (gethash var cache
) t
)))
70 (populate call-lexenv
))))))
72 (setf (lexenv-var-cache lexenv
) cache
))))
74 (defun leaf-visible-to-debugger-p (leaf node
)
75 (gethash leaf
(make-lexenv-var-cache (node-lexenv node
))))
77 ;;; Given a local conflicts vector and an IR2 block to represent the
78 ;;; set of live TNs, and the VAR-LOCS hash-table representing the
79 ;;; variables dumped, compute a bit-vector representing the set of
80 ;;; live variables. If the TN is environment-live, we only mark it as
81 ;;; live when it is in scope at NODE.
82 (defun compute-live-vars (live node block var-locs vop
)
83 (declare (type ir2-block block
) (type local-tn-bit-vector live
)
84 (type hash-table var-locs
) (type node node
)
85 (type (or vop null
) vop
))
86 (let ((res (make-array (logandc2 (+ (hash-table-count var-locs
) 7) 7)
90 (ir2-component-spilled-vops
91 (component-info *component-being-compiled
*)))))
92 (do-live-tns (tn live block
)
93 (let ((leaf (tn-leaf tn
)))
94 (when (and (lambda-var-p leaf
)
95 (or (not (member (tn-kind tn
)
96 '(:environment
:debug-environment
)))
97 (leaf-visible-to-debugger-p leaf node
))
99 (not (member tn spilled
))))
100 (let ((num (gethash leaf var-locs
)))
102 (setf (sbit res num
) 1))))))
105 ;;; The PC for the location most recently dumped.
106 (defvar *previous-location
*)
107 (declaim (type index
*previous-location
*))
109 ;;; Dump a compiled debug-location into *BYTE-BUFFER* that describes
110 ;;; the code/source map and live info. If true, VOP is the VOP
111 ;;; associated with this location, for use in determining whether TNs
113 (defun dump-1-location (node block kind tlf-num label live var-locs vop
)
114 (declare (type node node
) (type ir2-block block
)
115 (type (or null local-tn-bit-vector
) live
)
116 (type (or label index
) label
)
117 (type location-kind kind
) (type (or index null
) tlf-num
)
118 (type hash-table var-locs
) (type (or vop null
) vop
))
120 (let ((byte-buffer *byte-buffer
*))
122 (position-or-lose kind
*compiled-code-location-kinds
*)
125 (let ((loc (if (fixnump label
) label
(label-position label
))))
126 (write-var-integer (- loc
*previous-location
*) byte-buffer
)
127 (setq *previous-location
* loc
))
129 (let ((path (node-source-path node
)))
131 (write-var-integer (source-path-tlf-number path
) byte-buffer
))
132 (write-var-integer (source-path-form-number path
) byte-buffer
))
135 (write-packed-bit-vector (compute-live-vars live node block var-locs vop
)
137 (write-packed-bit-vector
138 (make-array (logandc2 (+ (hash-table-count var-locs
) 7) 7)
143 (write-var-string (or (and (typep node
'combination
)
144 (combination-step-info node
))
149 ;;; Extract context info from a Location-Info structure and use it to
150 ;;; dump a compiled code-location.
151 (defun dump-location-from-info (loc tlf-num var-locs
)
152 (declare (type location-info loc
) (type (or index null
) tlf-num
)
153 (type hash-table var-locs
))
154 (let ((vop (location-info-vop loc
)))
155 (dump-1-location (vop-node vop
)
157 (location-info-kind loc
)
159 (location-info-label loc
)
165 ;;; Scan all the blocks, determining if all locations are in the same
166 ;;; TLF, and returning it or NIL.
167 (defun find-tlf-number (fun)
168 (declare (type clambda fun
))
169 (let* ((source-path (node-source-path (lambda-bind fun
)))
170 (res (source-path-tlf-number source-path
)))
171 (declare (type (or index null
) res
))
172 (do-physenv-ir2-blocks (2block (lambda-physenv fun
))
173 (let ((block (ir2-block-block 2block
)))
174 (when (eq (block-info block
) 2block
)
175 (unless (eql (source-path-tlf-number
177 (block-start-node block
)))
181 (dolist (loc (ir2-block-locations 2block
))
182 (unless (eql (source-path-tlf-number
184 (vop-node (location-info-vop loc
))))
187 (values res
(source-path-form-number source-path
))))
189 ;;; Dump out the number of locations and the locations for Block.
190 (defun dump-block-locations (block locations tlf-num var-locs
)
191 (declare (type cblock block
) (list locations
))
193 (eq (location-info-kind (first locations
))
195 (write-var-integer (length locations
) *byte-buffer
*)
196 (let ((2block (block-info block
)))
197 (write-var-integer (+ (length locations
) 1) *byte-buffer
*)
198 (dump-1-location (block-start-node block
)
199 2block
:block-start tlf-num
200 (ir2-block-%label
2block
)
201 (ir2-block-live-out 2block
)
204 (dolist (loc locations
)
205 (dump-location-from-info loc tlf-num var-locs
))
208 ;;; Return a vector and an integer (or null) suitable for use as the
209 ;;; BLOCKS and TLF-NUMBER in FUN's DEBUG-FUN.
210 (defun compute-debug-blocks (fun var-locs
)
211 (declare (type clambda fun
) (type hash-table var-locs
))
212 (multiple-value-bind (tlf-num form-number
) (find-tlf-number fun
)
213 (let ((*previous-location
* 0)
214 (physenv (lambda-physenv fun
))
215 (byte-buffer *byte-buffer
*)
219 (setf (fill-pointer byte-buffer
) 0)
220 (do-physenv-ir2-blocks (2block physenv
)
221 (let ((block (ir2-block-block 2block
)))
222 (when (eq (block-info block
) 2block
)
224 (dump-block-locations prev-block
(nreverse (shiftf locations nil
))
226 (setf prev-block block
)))
227 (dolist (loc (ir2-block-locations 2block
))
228 (if (label-elsewhere-p (location-info-label loc
)
229 (location-info-kind loc
))
230 (push loc elsewhere-locations
)
231 (push loc locations
))))
233 (dump-block-locations prev-block
(nreverse locations
)
236 (when elsewhere-locations
237 (write-var-integer (length elsewhere-locations
) byte-buffer
)
238 (dolist (loc (nreverse elsewhere-locations
))
240 (dump-location-from-info loc tlf-num var-locs
)))
242 (values (!make-specialized-array
(length byte-buffer
) '(unsigned-byte 8)
244 tlf-num form-number
))))
246 ;;; Return DEBUG-SOURCE structure containing information derived from
248 (defun debug-source-for-info (info &key function
)
249 (declare (type source-info info
))
250 (let ((file-info (get-toplevelish-file-info info
)))
252 :compiled
(source-info-start-time info
)
254 :namestring
(or *source-namestring
*
255 (make-file-info-namestring
256 (if (pathnamep (file-info-name file-info
))
257 (file-info-name file-info
))
259 :created
(file-info-write-date file-info
)
260 :start-positions
(coerce-to-smallest-eltype
261 (file-info-positions file-info
))
263 :form
(let ((direct-file-info (source-info-file-info info
)))
264 (when (eq :lisp
(file-info-name direct-file-info
))
265 (elt (file-info-forms direct-file-info
) 0)))
266 :function function
)))
268 ;;; Given an arbitrary sequence, coerce it to an unsigned vector if
269 ;;; possible. Ordinarily we coerce it to the smallest specialized
271 ;;; During cross-compilation the in-memory representation is opaque -
272 ;;; we don't care how it looks, but can recover the intended specialization.
274 (defun coerce-to-smallest-eltype (seq)
275 (let ((maxoid 0) (length 0))
277 (if (typep x
'unsigned-byte
)
280 (return-from coerce-to-smallest-eltype
281 (coerce seq
'simple-vector
)))))
284 (incf length
) ; so not to traverse again to compute it
286 (dovector (i seq
(setq length
(length seq
)))
288 (let ((specializer (etypecase maxoid
289 ((unsigned-byte 8) '(unsigned-byte 8))
290 ((unsigned-byte 16) '(unsigned-byte 16))
291 ((unsigned-byte 32) '(unsigned-byte 32))
292 ((unsigned-byte 64) '(unsigned-byte 64)))))
293 ;; formerly (coerce seq `(simple-array ,specializer (*)))
294 ;; plus a kludge for cross-compilation. This is nicer.
295 (!make-specialized-array length specializer seq
)))))
299 ;;; Return a SC-OFFSET describing TN's location.
300 (defun tn-sc-offset (tn)
301 (declare (type tn tn
))
302 (make-sc-offset (sc-number (tn-sc tn
))
305 (defun lambda-ancestor-p (maybe-ancestor maybe-descendant
)
306 (declare (type clambda maybe-ancestor
)
307 (type (or clambda null
) maybe-descendant
))
309 (when (eq maybe-ancestor maybe-descendant
)
311 (setf maybe-descendant
(lambda-parent maybe-descendant
))
312 (when (null maybe-descendant
)
315 ;;; Dump info to represent VAR's location being TN. ID is an integer
316 ;;; that makes VAR's name unique in the function. BUFFER is the vector
317 ;;; we stick the result in. If MINIMAL, we suppress name dumping, and
318 ;;; set the minimal flag.
320 ;;; The DEBUG-VAR is only marked as always-live if the TN is
321 ;;; environment live and is an argument. If a :DEBUG-ENVIRONMENT TN,
322 ;;; then we also exclude set variables, since the variable is not
323 ;;; guaranteed to be live everywhere in that case.
324 (defun dump-1-var (fun var tn id minimal buffer
)
325 (declare (type lambda-var var
) (type (or tn null
) tn
) (type index id
)
327 (let* ((name (leaf-debug-name var
))
328 (save-tn (and tn
(tn-save-tn tn
)))
329 (kind (and tn
(tn-kind tn
)))
331 (info (lambda-var-arg-info var
))
332 (indirect (and (lambda-var-indirect var
)
333 (not (lambda-var-explicit-value-cell var
))
334 (neq (lambda-physenv fun
)
335 (lambda-physenv (lambda-var-home var
))))))
336 (declare (type index flags
))
338 (setq flags
(logior flags compiled-debug-var-minimal-p
))
339 (unless (and tn
(tn-offset tn
))
340 (setq flags
(logior flags compiled-debug-var-deleted-p
))))
341 (when (and (or (eq kind
:environment
)
342 (and (eq kind
:debug-environment
)
343 (null (basic-var-sets var
))))
344 (not (gethash tn
(ir2-component-spilled-tns
345 (component-info *component-being-compiled
*))))
346 (lambda-ancestor-p (lambda-var-home var
) fun
))
347 (setq flags
(logior flags compiled-debug-var-environment-live
)))
349 (setq flags
(logior flags compiled-debug-var-save-loc-p
)))
350 (unless (or (zerop id
) minimal
)
351 (setq flags
(logior flags compiled-debug-var-id-p
)))
353 (setq flags
(logior flags compiled-debug-var-indirect-p
)))
355 (case (arg-info-kind info
)
357 (setq flags
(logior flags compiled-debug-var-more-context-p
)))
359 (setq flags
(logior flags compiled-debug-var-more-count-p
)))))
362 (setf (ldb (byte 27 8) flags
) (tn-sc-offset tn
))
364 (setf (ldb (byte 27 35) flags
) (tn-sc-offset save-tn
))))
366 (if (and tn
(tn-offset tn
))
367 (setf (ldb (byte 27 8) flags
) (tn-sc-offset tn
))
370 (setf (ldb (byte 27 35) flags
) (tn-sc-offset save-tn
)))))
371 (vector-push-extend flags buffer
)
373 (vector-push-extend name buffer
)
375 (vector-push-extend id buffer
)))
378 ;; Indirect variables live in the parent frame, and are
379 ;; accessed through a saved frame pointer.
380 ;; The first one/two sc-offsets are for the frame pointer,
381 ;; the third is for the stack offset.
383 (vector-push-extend (tn-sc-offset tn
) buffer
)
386 (vector-push-extend (tn-sc-offset save-tn
) buffer
))
387 (vector-push-extend (tn-sc-offset (leaf-info var
)) buffer
))
390 (if (and tn
(tn-offset tn
))
391 (vector-push-extend (tn-sc-offset tn
) buffer
)
394 (vector-push-extend (tn-sc-offset save-tn
) buffer
)))))
397 ;;; Return a vector suitable for use as the DEBUG-FUN-VARS
398 ;;; of FUN. LEVEL is the current DEBUG-INFO quality. VAR-LOCS is a
399 ;;; hash table in which we enter the translation from LAMBDA-VARS to
400 ;;; the relative position of that variable's location in the resulting
402 (defun compute-vars (fun level var-locs
)
403 (declare (type clambda fun
) (type hash-table var-locs
))
405 (labels ((frob-leaf (leaf tn gensym-p
)
406 (let ((name (leaf-debug-name leaf
)))
407 (when (and name
(leaf-refs leaf
) (tn-offset tn
)
408 (or gensym-p
(symbol-package name
)))
409 (vars (cons leaf tn
)))))
410 (frob-lambda (x gensym-p
)
411 (dolist (leaf (lambda-vars x
))
412 (frob-leaf leaf
(leaf-info leaf
) gensym-p
))))
415 (dolist (x (ir2-physenv-closure (physenv-info (lambda-physenv fun
))))
416 (let ((thing (car x
)))
417 (when (lambda-var-p thing
)
418 (frob-leaf thing
(cdr x
) (= level
3)))))
420 (dolist (let (lambda-lets fun
))
421 (frob-lambda let
(= level
3)))))
423 (let ((sorted (sort (vars) #'string
<
425 (symbol-name (leaf-debug-name (car x
))))))
429 (buffer (make-array 0 :fill-pointer
0 :adjustable t
)))
430 (declare (type (or simple-string null
) prev-name
)
434 (name (symbol-name (leaf-debug-name var
))))
435 (cond ((and prev-name
(string= prev-name name
))
438 (setq id
0 prev-name name
)))
439 (dump-1-var fun var
(cdr x
) id nil buffer
)
440 (setf (gethash var var-locs
) i
)
442 (coerce buffer
'simple-vector
))))
444 ;;; Return a vector suitable for use as the DEBUG-FUN-VARS of
445 ;;; FUN, representing the arguments to FUN in minimal variable format.
446 (defun compute-minimal-vars (fun)
447 (declare (type clambda fun
))
448 (let ((buffer (make-array 0 :fill-pointer
0 :adjustable t
)))
449 (dolist (var (lambda-vars fun
))
450 (dump-1-var fun var
(leaf-info var
) 0 t buffer
))
451 (coerce buffer
'simple-vector
)))
453 ;;; Return VAR's relative position in the function's variables (determined
454 ;;; from the VAR-LOCS hashtable). If VAR is deleted, then return DELETED.
455 (defun debug-location-for (var var-locs
)
456 (declare (type lambda-var var
) (type hash-table var-locs
))
457 (let ((res (gethash var var-locs
)))
460 (aver (or (null (leaf-refs var
))
461 (not (tn-offset (leaf-info var
)))))
464 ;;;; arguments/returns
466 ;;; Return a vector to be used as the COMPILED-DEBUG-FUN-ARGS for FUN.
467 ;;; If FUN is the MAIN-ENTRY for an optional dispatch, then look at
468 ;;; the ARGLIST to determine the syntax, otherwise pretend all
469 ;;; arguments are fixed.
471 ;;; ### This assumption breaks down in EPs other than the main-entry,
472 ;;; since they may or may not have supplied-p vars, etc.
473 (defun compute-args (fun var-locs
)
474 (declare (type clambda fun
) (type hash-table var-locs
))
476 (let ((od (lambda-optional-dispatch fun
)))
477 (if (and od
(eq (optional-dispatch-main-entry od
) fun
))
478 (let ((actual-vars (lambda-vars fun
))
480 (labels ((one-arg (arg)
481 (let ((info (lambda-var-arg-info arg
))
482 (actual (pop actual-vars
)))
484 (case (arg-info-kind info
)
486 (res (arg-info-key info
)))
488 (let ((more (arg-info-default info
)))
489 (cond ((and (consp more
) (third more
))
490 (one-arg (first (arg-info-default info
)))
491 (one-arg (second (arg-info-default info
)))
492 (return-from one-arg
))
494 (setf (arg-info-default info
) t
)))
501 (setq saw-optional t
))))
502 (res (debug-location-for actual var-locs
))
503 (when (arg-info-supplied-p info
)
505 (res (debug-location-for (pop actual-vars
) var-locs
))))
507 (res (debug-location-for actual var-locs
)))))))
508 (dolist (arg (optional-dispatch-arglist od
))
510 (dolist (var (lambda-vars fun
))
511 (res (debug-location-for var var-locs
)))))
513 (coerce-to-smallest-eltype (res))))
515 ;;; Return a vector of SC offsets describing FUN's return locations.
516 ;;; (Must be known values return...)
517 (defun compute-debug-returns (fun)
518 (coerce-to-smallest-eltype
519 (mapcar (lambda (loc)
521 (return-info-locations (tail-set-info (lambda-tail-set fun
))))))
525 ;;; Return a C-D-F structure with all the mandatory slots filled in.
526 (defun dfun-from-fun (fun)
527 (declare (type clambda fun
))
528 (let* ((2env (physenv-info (lambda-physenv fun
)))
529 (dispatch (lambda-optional-dispatch fun
))
530 (main-p (and dispatch
531 (eq fun
(optional-dispatch-main-entry dispatch
)))))
532 (make-compiled-debug-fun
533 :name
(leaf-debug-name fun
)
534 :kind
(if main-p nil
(functional-kind fun
))
535 #!-fp-and-pc-standard-save
:return-pc
536 #!-fp-and-pc-standard-save
(tn-sc-offset (ir2-physenv-return-pc 2env
))
537 #!-fp-and-pc-standard-save
:old-fp
538 #!-fp-and-pc-standard-save
(tn-sc-offset (ir2-physenv-old-fp 2env
))
539 :start-pc
(label-position (ir2-physenv-environment-start 2env
))
540 :elsewhere-pc
(label-position (ir2-physenv-elsewhere-start 2env
))
541 :closure-save
(when (ir2-physenv-closure-save-tn 2env
)
542 (tn-sc-offset (ir2-physenv-closure-save-tn 2env
)))
543 #!+unwind-to-frame-and-call-vop
545 #!+unwind-to-frame-and-call-vop
546 (when (ir2-physenv-bsp-save-tn 2env
)
547 (tn-sc-offset (ir2-physenv-bsp-save-tn 2env
))))))
549 ;;; Return a complete C-D-F structure for FUN. This involves
550 ;;; determining the DEBUG-INFO level and filling in optional slots as
552 (defun compute-1-debug-fun (fun var-locs
)
553 (declare (type clambda fun
) (type hash-table var-locs
))
554 (let* ((dfun (dfun-from-fun fun
))
555 (actual-level (policy (lambda-bind fun
) compute-debug-fun
))
556 (level (if #!+sb-dyncount
*collect-dynamic-statistics
*
560 (toplevel-p (eq :toplevel
(compiled-debug-fun-kind dfun
))))
561 (cond ((or (zerop level
) toplevel-p
))
563 (let ((od (lambda-optional-dispatch fun
)))
565 (not (eq (optional-dispatch-main-entry od
) fun
)))))
566 (setf (compiled-debug-fun-vars dfun
)
567 (compute-minimal-vars fun
))
568 (setf (compiled-debug-fun-arguments dfun
) :minimal
))
570 (setf (compiled-debug-fun-vars dfun
)
571 (compute-vars fun level var-locs
))
572 (setf (compiled-debug-fun-arguments dfun
)
573 (compute-args fun var-locs
))))
575 (if (and (>= level
2) (not toplevel-p
))
576 (multiple-value-bind (blocks tlf-num form-number
)
577 (compute-debug-blocks fun var-locs
)
578 (setf (compiled-debug-fun-blocks dfun
) blocks
579 (compiled-debug-fun-tlf-number dfun
) tlf-num
580 (compiled-debug-fun-form-number dfun
) form-number
))
581 (multiple-value-bind (tlf-num form-number
) (find-tlf-number fun
)
582 (setf (compiled-debug-fun-tlf-number dfun
) tlf-num
583 (compiled-debug-fun-form-number dfun
) form-number
)))
585 (setf (compiled-debug-fun-returns dfun
) :standard
)
586 (let ((info (tail-set-info (lambda-tail-set fun
))))
588 (cond ((eq (return-info-kind info
) :unknown
)
589 (setf (compiled-debug-fun-returns dfun
)
592 (setf (compiled-debug-fun-returns dfun
)
593 (compute-debug-returns fun
)))))))
596 ;;;; full component dumping
598 ;;; Compute the full form (simple-vector) function map.
599 (defun compute-debug-fun-map (sorted)
600 (declare (list sorted
))
601 (let* ((len (1- (* (length sorted
) 2)))
602 (funs-vec (make-array len
)))
604 (sorted sorted
(cdr sorted
)))
607 (let ((dfun (car sorted
)))
609 (setf (svref funs-vec i
) (car dfun
)))
610 (setf (svref funs-vec
(1+ i
)) (cdr dfun
))))
613 ;;; Return a DEBUG-INFO structure describing COMPONENT. This has to be
614 ;;; called after assembly so that source map information is available.
615 (defun debug-info-for-component (component)
616 (declare (type component component
))
618 (var-locs (make-hash-table :test
'eq
))
619 (*byte-buffer
* (make-array 10
620 :element-type
'(unsigned-byte 8)
623 (dolist (lambda (component-lambdas component
))
625 (push (cons (label-position (block-label (lambda-block lambda
)))
626 (compute-1-debug-fun lambda var-locs
))
628 (let* ((sorted (sort dfuns
#'< :key
#'car
))
629 (fun-map (compute-debug-fun-map sorted
)))
630 (make-compiled-debug-info :name
(component-name component
)
633 ;;; Write BITS out to BYTE-BUFFER in backend byte order. The length of
634 ;;; BITS must be evenly divisible by eight.
635 (defun write-packed-bit-vector (bits byte-buffer
)
636 (declare (type simple-bit-vector bits
) (type byte-buffer byte-buffer
))
638 ;; Enforce constraint from CMU-CL-era comment.
639 (aver (zerop (mod (length bits
) 8)))
641 (multiple-value-bind (initial step done
)
642 (ecase *backend-byte-order
*
643 (:little-endian
(values 0 1 8))
644 (:big-endian
(values 7 -
1 -
1)))
645 (let ((shift initial
)
647 (dotimes (i (length bits
))
648 (let ((int (aref bits i
)))
649 (setf byte
(logior byte
(ash int shift
)))
652 (vector-push-extend byte byte-buffer
)
655 (unless (= shift initial
)
656 (vector-push-extend byte byte-buffer
))))