1 ;;;; optimizers for list and sequence functions
3 ;;;; This software is part of the SBCL system. See the README file for
6 ;;;; This software is derived from the CMU CL system, which was
7 ;;;; written at Carnegie Mellon University and released into the
8 ;;;; public domain. The software is in the public domain and is
9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
10 ;;;; files for more information.
14 ;;;; mapping onto lists: the MAPFOO functions
16 (defun mapfoo-transform (fn arglists accumulate take-car)
17 (collect ((do-clauses)
20 (let ((n-first (gensym)))
21 (dolist (a (if accumulate
23 `(,n-first ,@(rest arglists))))
25 (do-clauses `(,v ,a (cdr ,v)))
27 (args-to-fn (if take-car `(car ,v) v))))
29 (let* ((fn-sym (gensym)) ; for ONCE-ONLY-ish purposes
30 (call `(funcall ,fn-sym . ,(args-to-fn)))
31 (endtest `(or ,@(tests))))
35 (map-result (gensym)))
37 (,map-result (list nil)))
38 (do-anonymous ((,temp ,map-result) . ,(do-clauses))
39 (,endtest (cdr ,map-result))
40 (setq ,temp (last (nconc ,temp ,call)))))))
43 (map-result (gensym)))
45 (,map-result (list nil)))
46 (do-anonymous ((,temp ,map-result) . ,(do-clauses))
47 (,endtest (cdr ,map-result))
48 (rplacd ,temp (setq ,temp (list ,call)))))))
51 (,n-first ,(first arglists)))
52 (do-anonymous ,(do-clauses)
53 (,endtest ,n-first) ,call))))))))
55 (define-source-transform mapc (function list &rest more-lists)
56 (mapfoo-transform function (cons list more-lists) nil t))
58 (define-source-transform mapcar (function list &rest more-lists)
59 (mapfoo-transform function (cons list more-lists) :list t))
61 (define-source-transform mapcan (function list &rest more-lists)
62 (mapfoo-transform function (cons list more-lists) :nconc t))
64 (define-source-transform mapl (function list &rest more-lists)
65 (mapfoo-transform function (cons list more-lists) nil nil))
67 (define-source-transform maplist (function list &rest more-lists)
68 (mapfoo-transform function (cons list more-lists) :list nil))
70 (define-source-transform mapcon (function list &rest more-lists)
71 (mapfoo-transform function (cons list more-lists) :nconc nil))
73 ;;;; mapping onto sequences: the MAP function
75 ;;; MAP is %MAP plus a check to make sure that any length specified in
76 ;;; the result type matches the actual result. We also wrap it in a
77 ;;; TRULY-THE for the most specific type we can determine.
78 (deftransform map ((result-type-arg fun seq &rest seqs) * * :node node)
79 (let* ((seq-names (make-gensym-list (1+ (length seqs))))
80 (bare `(%map result-type-arg fun ,@seq-names))
81 (constant-result-type-arg-p (constant-continuation-p result-type-arg))
82 ;; what we know about the type of the result. (Note that the
83 ;; "result type" argument is not necessarily the type of the
84 ;; result, since NIL means the result has NULL type.)
85 (result-type (if (not constant-result-type-arg-p)
87 (let ((result-type-arg-value
88 (continuation-value result-type-arg)))
89 (if (null result-type-arg-value)
91 result-type-arg-value)))))
92 `(lambda (result-type-arg fun ,@seq-names)
93 (truly-the ,result-type
94 ,(cond ((policy node (< safety 3))
95 ;; ANSI requires the length-related type check only
96 ;; when the SAFETY quality is 3... in other cases, we
97 ;; skip it, because it could be expensive.
99 ((not constant-result-type-arg-p)
100 `(sequence-of-checked-length-given-type ,bare
103 (let ((result-ctype (ir1-transform-specifier-type
105 (if (array-type-p result-ctype)
106 (let ((dims (array-type-dimensions result-ctype)))
107 (unless (and (listp dims) (= (length dims) 1))
108 (give-up-ir1-transform "invalid sequence type"))
109 (let ((dim (first dims)))
112 `(vector-of-checked-length-given-length ,bare
114 ;; FIXME: this is wrong, as not all subtypes of
115 ;; VECTOR are ARRAY-TYPEs [consider, for
116 ;; example, (OR (VECTOR T 3) (VECTOR T
117 ;; 4))]. However, it's difficult to see what we
118 ;; should put here... maybe we should
119 ;; GIVE-UP-IR1-TRANSFORM if the type is a
120 ;; subtype of VECTOR but not an ARRAY-TYPE?
123 ;;; Return a DO loop, mapping a function FUN to elements of
124 ;;; sequences. SEQS is a list of continuations, SEQ-NAMES - list of
125 ;;; variables, bound to sequences, INTO - a variable, which is used in
126 ;;; MAP-INTO. RESULT and BODY are forms, which can use variables
127 ;;; FUNCALL-RESULT, containing the result of application of FUN, and
128 ;;; INDEX, containing the current position in sequences.
129 (defun build-sequence-iterator (seqs seq-names &key result into body)
130 (declare (type list seqs seq-names)
137 (let ((found-vector-p nil))
138 (flet ((process-vector (length)
139 (unless found-vector-p
140 (setq found-vector-p t)
141 (bindings `(index 0 (1+ index)))
142 (declarations `(type index index)))
143 (vector-lengths length)))
144 (loop for seq of-type continuation in seqs
145 for seq-name in seq-names
146 for type = (continuation-type seq)
147 do (cond ((csubtypep type (specifier-type 'list))
148 (with-unique-names (index)
149 (bindings `(,index ,seq-name (cdr ,index)))
150 (declarations `(type list ,index))
151 (places `(car ,index))
152 (tests `(endp ,index))))
153 ((csubtypep type (specifier-type 'vector))
154 (process-vector `(length ,seq-name))
155 (places `(aref ,seq-name index)))
157 (give-up-ir1-transform
158 "can't determine sequence argument type"))))
160 (process-vector `(array-dimension ,into 0))))
162 (bindings `(length (min ,@(vector-lengths))))
163 (tests `(= index length)))
165 ((or ,@(tests)) ,result)
166 (declare ,@(declarations))
167 (let ((funcall-result (funcall fun ,@(places))))
168 (declare (ignorable funcall-result))
171 ;;; Try to compile %MAP efficiently when we can determine sequence
172 ;;; argument types at compile time.
174 ;;; Note: This transform was written to allow open coding of
175 ;;; quantifiers by expressing them in terms of (MAP NIL ..). For
176 ;;; non-NIL values of RESULT-TYPE, it's still useful, but not
177 ;;; necessarily as efficient as possible. In particular, it will be
178 ;;; inefficient when RESULT-TYPE is a SIMPLE-ARRAY with specialized
179 ;;; numeric element types. It should be straightforward to make it
180 ;;; handle that case more efficiently, but it's left as an exercise to
181 ;;; the reader, because the code is complicated enough already and I
182 ;;; don't happen to need that functionality right now. -- WHN 20000410
183 (deftransform %map ((result-type fun seq &rest seqs) * *
184 :policy (>= speed space))
186 (unless (constant-continuation-p result-type)
187 (give-up-ir1-transform "RESULT-TYPE argument not constant"))
188 (labels ( ;; 1-valued SUBTYPEP, fails unless second value of SUBTYPEP is true
189 (fn-1subtypep (fn x y)
190 (multiple-value-bind (subtype-p valid-p) (funcall fn x y)
193 (give-up-ir1-transform
194 "can't analyze sequence type relationship"))))
195 (1subtypep (x y) (fn-1subtypep #'sb!xc:subtypep x y)))
196 (let* ((result-type-value (continuation-value result-type))
197 (result-supertype (cond ((null result-type-value) 'null)
198 ((1subtypep result-type-value 'vector)
200 ((1subtypep result-type-value 'list)
203 (give-up-ir1-transform
204 "can't determine result type")))))
205 (cond ((and result-type-value (null seqs))
206 ;; The consing arity-1 cases can be implemented
207 ;; reasonably efficiently as function calls, and the cost
208 ;; of consing should be significantly larger than
209 ;; function call overhead, so we always compile these
210 ;; cases as full calls regardless of speed-versus-space
211 ;; optimization policy.
212 (cond ((subtypep result-type-value 'list)
213 '(%map-to-list-arity-1 fun seq))
214 ( ;; (This one can be inefficient due to COERCE, but
215 ;; the current open-coded implementation has the
217 (subtypep result-type-value 'vector)
218 `(coerce (%map-to-simple-vector-arity-1 fun seq)
219 ',result-type-value))
220 (t (bug "impossible (?) sequence type"))))
222 (let* ((seqs (cons seq seqs))
223 (seq-args (make-gensym-list (length seqs))))
224 (multiple-value-bind (push-dacc result)
225 (ecase result-supertype
226 (null (values nil nil))
227 (list (values `(push funcall-result acc)
229 (vector (values `(push funcall-result acc)
230 `(coerce (nreverse acc)
231 ',result-type-value))))
232 ;; (We use the same idiom, of returning a LAMBDA from
233 ;; DEFTRANSFORM, as is used in the DEFTRANSFORMs for
234 ;; FUNCALL and ALIEN-FUNCALL, and for the same
235 ;; reason: we need to get the runtime values of each
236 ;; of the &REST vars.)
237 `(lambda (result-type fun ,@seq-args)
238 (declare (ignore result-type))
239 (let ((fun (%coerce-callable-to-fun fun))
241 (declare (type list acc))
242 (declare (ignorable acc))
243 ,(build-sequence-iterator
246 :body push-dacc))))))))))
249 (deftransform map-into ((result fun &rest seqs)
253 (let ((seqs-names (mapcar (lambda (x)
257 `(lambda (result fun ,@seqs-names)
258 ,(build-sequence-iterator
260 :result '(when (array-has-fill-pointer-p result)
261 (setf (fill-pointer result) index))
263 :body '(setf (aref result index) funcall-result))
267 ;;; FIXME: once the confusion over doing transforms with known-complex
268 ;;; arrays is over, we should also transform the calls to (AND (ARRAY
269 ;;; * (*)) (NOT (SIMPLE-ARRAY * (*)))) objects.
270 (deftransform elt ((s i) ((simple-array * (*)) *) *)
273 (deftransform elt ((s i) (list *) * :policy (< safety 3))
276 (deftransform %setelt ((s i v) ((simple-array * (*)) * *) *)
279 (deftransform %setelt ((s i v) (list * *) * :policy (< safety 3))
280 '(setf (car (nthcdr i s)) v))
282 (deftransform %check-vector-sequence-bounds ((vector start end)
285 (if (policy node (< safety speed))
286 '(or end (length vector))
287 '(let ((length (length vector)))
288 (if (<= 0 start (or end length) length)
290 (sb!impl::signal-bounding-indices-bad-error vector start end)))))
292 (macrolet ((def (name)
293 `(deftransform ,name ((e l &key (test #'eql)) * *
295 (unless (constant-continuation-p l)
296 (give-up-ir1-transform))
298 (let ((val (continuation-value l)))
301 (and (>= speed space)
302 (<= (length val) 5))))
303 (give-up-ir1-transform))
307 `(if (funcall test e ',(car els))
315 ;;; FIXME: We have rewritten the original code that used DOLIST to this
316 ;;; more natural MACROLET. However, the original code suggested that when
317 ;;; this was done, a few bytes could be saved by a call to a shared
318 ;;; function. This remains to be done.
319 (macrolet ((def (fun eq-fun)
320 `(deftransform ,fun ((item list &key test) (t list &rest t) *)
322 ;; FIXME: The scope of this transformation could be
323 ;; widened somewhat, letting it work whenever the test is
324 ;; 'EQL and we know from the type of ITEM that it #'EQ
325 ;; works like #'EQL on it. (E.g. types FIXNUM, CHARACTER,
327 ;; If TEST is EQ, apply transform, else
328 ;; if test is not EQL, then give up on transform, else
329 ;; if ITEM is not a NUMBER or is a FIXNUM, apply
330 ;; transform, else give up on transform.
332 (unless (continuation-fun-is test '(eq))
333 (give-up-ir1-transform)))
334 ((types-equal-or-intersect (continuation-type item)
335 (specifier-type 'number))
336 (give-up-ir1-transform "Item might be a number.")))
337 `(,',eq-fun item list))))
342 (deftransform delete-if ((pred list) (t list))
344 '(do ((x list (cdr x))
347 (cond ((funcall pred (car x))
350 (rplacd splice (cdr x))))
351 (T (setq splice x)))))
353 (deftransform fill ((seq item &key (start 0) (end (length seq)))
354 (vector t &key (:start t) (:end index))
356 :policy (> speed space))
358 (let ((element-type (upgraded-element-type-specifier-or-give-up seq)))
360 `(with-array-data ((data seq)
363 (declare (type (simple-array ,element-type 1) data))
364 (declare (type fixnum start end))
365 (do ((i start (1+ i)))
367 (declare (type index i))
368 ;; WITH-ARRAY-DATA did our range checks once and for all, so
369 ;; it'd be wasteful to check again on every AREF...
370 (declare (optimize (safety 0)))
371 (setf (aref data i) item)))
372 ;; ... though we still need to check that the new element can fit
373 ;; into the vector in safe code. -- CSR, 2002-07-05
374 `((declare (type ,element-type item))))))
378 ;;; Return true if CONT's only use is a non-NOTINLINE reference to a
379 ;;; global function with one of the specified NAMES.
380 (defun continuation-fun-is (cont names)
381 (declare (type continuation cont) (list names))
382 (let ((use (continuation-use cont)))
384 (let ((leaf (ref-leaf use)))
385 (and (global-var-p leaf)
386 (eq (global-var-kind leaf) :global-function)
387 (not (null (member (leaf-source-name leaf) names
388 :test #'equal))))))))
390 ;;; If CONT is a constant continuation, the return the constant value.
391 ;;; If it is null, then return default, otherwise quietly give up the
394 ;;; ### Probably should take an ARG and flame using the NAME.
395 (defun constant-value-or-lose (cont &optional default)
396 (declare (type (or continuation null) cont))
397 (cond ((not cont) default)
398 ((constant-continuation-p cont)
399 (continuation-value cont))
401 (give-up-ir1-transform))))
403 ;;; FIXME: Why is this code commented out? (Why *was* it commented
404 ;;; out? We inherited this situation from cmucl-2.4.8, with no
405 ;;; explanation.) Should we just delete this code?
407 ;;; This is a frob whose job it is to make it easier to pass around
408 ;;; the arguments to IR1 transforms. It bundles together the name of
409 ;;; the argument (which should be referenced in any expansion), and
410 ;;; the continuation for that argument (or NIL if unsupplied.)
411 (defstruct (arg (:constructor %make-arg (name cont))
413 (name nil :type symbol)
414 (cont nil :type (or continuation null)))
415 (defmacro make-arg (name)
416 `(%make-arg ',name ,name))
418 ;;; If Arg is null or its CONT is null, then return Default, otherwise
419 ;;; return Arg's NAME.
420 (defun default-arg (arg default)
421 (declare (type (or arg null) arg))
422 (if (and arg (arg-cont arg))
426 ;;; If Arg is null or has no CONT, return the default. Otherwise, Arg's
427 ;;; CONT must be a constant continuation whose value we return. If not, we
429 (defun arg-constant-value (arg default)
430 (declare (type (or arg null) arg))
431 (if (and arg (arg-cont arg))
432 (let ((cont (arg-cont arg)))
433 (unless (constant-continuation-p cont)
434 (give-up-ir1-transform "Argument is not constant: ~S."
436 (continuation-value from-end))
439 ;;; If Arg is a constant and is EQL to X, then return T, otherwise NIL. If
440 ;;; Arg is NIL or its CONT is NIL, then compare to the default.
441 (defun arg-eql (arg default x)
442 (declare (type (or arg null) x))
443 (if (and arg (arg-cont arg))
444 (let ((cont (arg-cont arg)))
445 (and (constant-continuation-p cont)
446 (eql (continuation-value cont) x)))
449 (defstruct (iterator (:copier nil))
450 ;; The kind of iterator.
451 (kind nil (member :normal :result))
452 ;; A list of LET* bindings to create the initial state.
453 (binds nil :type list)
454 ;; A list of declarations for Binds.
455 (decls nil :type list)
456 ;; A form that returns the current value. This may be set with SETF to set
457 ;; the current value.
458 (current (error "Must specify CURRENT."))
459 ;; In a :NORMAL iterator, a form that tests whether there is a current value.
461 ;; In a :RESULT iterator, a form that truncates the result at the current
462 ;; position and returns it.
464 ;; A form that returns the initial total number of values. The result is
465 ;; undefined after NEXT has been evaluated.
466 (length (error "Must specify LENGTH."))
467 ;; A form that advances the state to the next value. It is an error to call
468 ;; this when the iterator is Done.
469 (next (error "Must specify NEXT.")))
471 ;;; Type of an index var that can go negative (in the from-end case.)
472 (deftype neg-index ()
473 `(integer -1 ,most-positive-fixnum))
475 ;;; Return an ITERATOR structure describing how to iterate over an arbitrary
476 ;;; sequence. Sequence is a variable bound to the sequence, and Type is the
477 ;;; type of the sequence. If true, INDEX is a variable that should be bound to
478 ;;; the index of the current element in the sequence.
480 ;;; If we can't tell whether the sequence is a list or a vector, or whether
481 ;;; the iteration is forward or backward, then GIVE-UP.
482 (defun make-sequence-iterator (sequence type &key start end from-end index)
483 (declare (symbol sequence) (type ctype type)
484 (type (or arg null) start end from-end)
485 (type (or symbol null) index))
486 (let ((from-end (arg-constant-value from-end nil)))
487 (cond ((csubtypep type (specifier-type 'vector))
488 (let* ((n-stop (gensym))
489 (n-idx (or index (gensym)))
490 (start (default-arg 0 start))
491 (end (default-arg `(length ,sequence) end)))
494 :binds `((,n-idx ,(if from-end `(1- ,end) ,start))
495 (,n-stop ,(if from-end `(1- ,start) ,end)))
496 :decls `((type neg-index ,n-idx ,n-stop))
497 :current `(aref ,sequence ,n-idx)
498 :done `(,(if from-end '<= '>=) ,n-idx ,n-stop)
500 ,(if from-end `(1- ,n-idx) `(1+ ,n-idx)))
503 `(- ,n-stop ,n-idx)))))
504 ((csubtypep type (specifier-type 'list))
505 (let* ((n-stop (if (and end (not from-end)) (gensym) nil))
507 (start-p (not (arg-eql start 0 0)))
508 (end-p (not (arg-eql end nil nil)))
509 (start (default-arg start 0))
510 (end (default-arg end nil)))
514 (if (or start-p end-p)
515 `(nreverse (subseq ,sequence ,start
516 ,@(when end `(,end))))
517 `(reverse ,sequence))
519 `(nthcdr ,start ,sequence)
522 `((,n-stop (nthcdr (the index
526 `((,index ,(if from-end `(1- ,end) start)))))
528 :decls `((list ,n-current ,n-end)
529 ,@(when index `((type neg-index ,index))))
530 :current `(car ,n-current)
531 :done `(eq ,n-current ,n-stop)
532 :length `(- ,(or end `(length ,sequence)) ,start)
534 (setq ,n-current (cdr ,n-current))
541 (give-up-ir1-transform
542 "can't tell whether sequence is a list or a vector")))))
544 ;;; Make an iterator used for constructing result sequences. Name is a
545 ;;; variable to be bound to the result sequence. Type is the type of result
546 ;;; sequence to make. Length is an expression to be evaluated to get the
547 ;;; maximum length of the result (not evaluated in list case.)
548 (defun make-result-sequence-iterator (name type length)
549 (declare (symbol name) (type ctype type))
551 ;;; Define each NAME as a local macro that will call the value of the
552 ;;; function arg with the given arguments. If the argument isn't known to be a
553 ;;; function, give them an efficiency note and reference a coerced version.
554 (defmacro coerce-funs (specs &body body)
556 "COERCE-FUNCTIONS ({(Name Fun-Arg Default)}*) Form*"
560 `(let ((body (progn ,@body))
561 (n-fun (arg-name ,(second spec)))
562 (fun-cont (arg-cont ,(second spec))))
563 (cond ((not fun-cont)
564 `(macrolet ((,',(first spec) (&rest args)
565 `(,',',(third spec) ,@args)))
567 ((not (csubtypep (continuation-type fun-cont)
568 (specifier-type 'function)))
569 (when (policy *compiler-error-context*
570 (> speed inhibit-warnings))
572 "~S may not be a function, so must coerce at run-time."
574 (once-only ((n-fun `(if (functionp ,n-fun)
576 (symbol-function ,n-fun))))
577 `(macrolet ((,',(first spec) (&rest args)
578 `(funcall ,',n-fun ,@args)))
581 `(macrolet ((,',(first spec) (&rest args)
582 `(funcall ,',n-fun ,@args)))
585 ;;; Wrap code around the result of the body to define Name as a local macro
586 ;;; that returns true when its arguments satisfy the test according to the Args
587 ;;; Test and Test-Not. If both Test and Test-Not are supplied, abort the
589 (defmacro with-sequence-test ((name test test-not) &body body)
590 `(let ((not-p (arg-cont ,test-not)))
591 (when (and (arg-cont ,test) not-p)
592 (abort-ir1-transform "Both ~S and ~S were supplied."
594 (arg-name ,test-not)))
595 (coerce-funs ((,name (if not-p ,test-not ,test) eql))
599 ;;;; hairy sequence transforms
601 ;;; FIXME: no hairy sequence transforms in SBCL?
603 ;;;; string operations
605 ;;; We transform the case-sensitive string predicates into a non-keyword
606 ;;; version. This is an IR1 transform so that we don't have to worry about
607 ;;; changing the order of evaluation.
608 (macrolet ((def (fun pred*)
609 `(deftransform ,fun ((string1 string2 &key (start1 0) end1
612 `(,',pred* string1 string2 start1 end1 start2 end2))))
613 (def string< string<*)
614 (def string> string>*)
615 (def string<= string<=*)
616 (def string>= string>=*)
617 (def string= string=*)
618 (def string/= string/=*))
620 ;;; Return a form that tests the free variables STRING1 and STRING2
621 ;;; for the ordering relationship specified by LESSP and EQUALP. The
622 ;;; start and end are also gotten from the environment. Both strings
623 ;;; must be SIMPLE-STRINGs.
624 (macrolet ((def (name lessp equalp)
625 `(deftransform ,name ((string1 string2 start1 end1 start2 end2)
626 (simple-string simple-string t t t t) *)
627 `(let* ((end1 (if (not end1) (length string1) end1))
628 (end2 (if (not end2) (length string2) end2))
629 (index (sb!impl::%sp-string-compare
630 string1 start1 end1 string2 start2 end2)))
632 (cond ((= index ,(if ',lessp 'end1 'end2)) index)
633 ((= index ,(if ',lessp 'end2 'end1)) nil)
634 ((,(if ',lessp 'char< 'char>)
635 (schar string1 index)
644 ,(if ',equalp 'end1 nil))))))
647 (def string>* nil nil)
648 (def string>=* nil t))
650 (macrolet ((def (name result-fun)
651 `(deftransform ,name ((string1 string2 start1 end1 start2 end2)
652 (simple-string simple-string t t t t) *)
654 (sb!impl::%sp-string-compare
655 string1 start1 (or end1 (length string1))
656 string2 start2 (or end2 (length string2)))))))
658 (def string/=* identity))
661 ;;;; string-only transforms for sequence functions
663 ;;;; Note: CMU CL had more of these, including transforms for
664 ;;;; functions which cons. In SBCL, we've gotten rid of most of the
665 ;;;; transforms for functions which cons, since our GC overhead is
666 ;;;; sufficiently large that it doesn't seem worth it to try to
667 ;;;; economize on function call overhead or on the overhead of runtime
668 ;;;; type dispatch in AREF. The exception is CONCATENATE, since
669 ;;;; a full call to CONCATENATE would have to look up the sequence
670 ;;;; type, which can be really slow.
672 ;;;; FIXME: It would be nicer for these transforms to work for any
673 ;;;; calls when all arguments are vectors with the same element type,
674 ;;;; rather than restricting them to STRINGs only.
676 ;;; Moved here from generic/vm-tran.lisp to satisfy clisp
678 ;;; FIXME: Add a comment telling whether this holds for all vectors
679 ;;; or only for vectors based on simple arrays (non-adjustable, etc.).
680 (def!constant vector-data-bit-offset
681 (* sb!vm:vector-data-offset sb!vm:n-word-bits))
683 (deftransform replace ((string1 string2 &key (start1 0) (start2 0)
685 (simple-string simple-string &rest t)
687 ;; FIXME: consider replacing this policy test
688 ;; with some tests for the STARTx and ENDx
689 ;; indices being valid, conditional on high
692 ;; FIXME: It turns out that this transform is
693 ;; critical for the performance of string
694 ;; streams. Make this more explicit.
695 :policy (< (max safety space) 3))
697 (declare (optimize (safety 0)))
698 (bit-bash-copy string2
700 (+ (the index (* start2 sb!vm:n-byte-bits))
701 ,vector-data-bit-offset))
704 (+ (the index (* start1 sb!vm:n-byte-bits))
705 ,vector-data-bit-offset))
707 (* (min (the index (- (or end1 (length string1))
709 (the index (- (or end2 (length string2))
714 ;;; FIXME: It seems as though it should be possible to make a DEFUN
715 ;;; %CONCATENATE (with a DEFTRANSFORM to translate constant RTYPE to
716 ;;; CTYPE before calling %CONCATENATE) which is comparably efficient,
717 ;;; at least once DYNAMIC-EXTENT works.
719 ;;; FIXME: currently KLUDGEed because of bug 188
720 (deftransform concatenate ((rtype &rest sequences)
721 (t &rest simple-string)
723 :policy (< safety 3))
728 (dolist (seq sequences)
729 (declare (ignorable seq))
730 (let ((n-seq (gensym))
733 (lets `(,n-length (the index (* (length ,n-seq) sb!vm:n-byte-bits))))
734 (all-lengths n-length)
735 (forms `(bit-bash-copy ,n-seq ,vector-data-bit-offset
738 (forms `(setq start (opaque-identity (+ start ,n-length))))))
739 `(lambda (rtype ,@(args))
740 (declare (ignore rtype))
742 (flet ((opaque-identity (x) x))
743 (declare (notinline opaque-identity))
745 (res (make-string (truncate (the index (+ ,@(all-lengths)))
747 (start ,vector-data-bit-offset))
748 (declare (type index start ,@(all-lengths)))
752 ;;;; CONS accessor DERIVE-TYPE optimizers
754 (defoptimizer (car derive-type) ((cons))
755 (let ((type (continuation-type cons))
756 (null-type (specifier-type 'null)))
757 (cond ((eq type null-type)
760 (cons-type-car-type type)))))
762 (defoptimizer (cdr derive-type) ((cons))
763 (let ((type (continuation-type cons))
764 (null-type (specifier-type 'null)))
765 (cond ((eq type null-type)
768 (cons-type-cdr-type type)))))
770 ;;;; FIND, POSITION, and their -IF and -IF-NOT variants
772 ;;; We want to make sure that %FIND-POSITION is inline-expanded into
773 ;;; %FIND-POSITION-IF only when %FIND-POSITION-IF has an inline
774 ;;; expansion, so we factor out the condition into this function.
775 (defun check-inlineability-of-find-position-if (sequence from-end)
776 (let ((ctype (continuation-type sequence)))
777 (cond ((csubtypep ctype (specifier-type 'vector))
778 ;; It's not worth trying to inline vector code unless we
779 ;; know a fair amount about it at compile time.
780 (upgraded-element-type-specifier-or-give-up sequence)
781 (unless (constant-continuation-p from-end)
782 (give-up-ir1-transform
783 "FROM-END argument value not known at compile time")))
784 ((csubtypep ctype (specifier-type 'list))
785 ;; Inlining on lists is generally worthwhile.
788 (give-up-ir1-transform
789 "sequence type not known at compile time")))))
791 ;;; %FIND-POSITION-IF and %FIND-POSITION-IF-NOT for LIST data
792 (macrolet ((def (name condition)
793 `(deftransform ,name ((predicate sequence from-end start end key)
794 (function list t t t function)
796 :policy (> speed space)
802 (declare (type index index))
804 (if (and end (> end index))
805 (sb!impl::signal-bounding-indices-bad-error
807 (values find position)))
808 (let ((key-i (funcall key i)))
809 (when (and end (>= index end))
810 (return (values find position)))
811 (when (>= index start)
812 (,',condition (funcall predicate key-i)
813 ;; This hack of dealing with non-NIL
814 ;; FROM-END for list data by iterating
815 ;; forward through the list and keeping
816 ;; track of the last time we found a match
817 ;; might be more screwy than what the user
818 ;; expects, but it seems to be allowed by
819 ;; the ANSI standard. (And if the user is
820 ;; screwy enough to ask for FROM-END
821 ;; behavior on list data, turnabout is
824 ;; It's also not enormously efficient,
825 ;; calling PREDICATE and KEY more often
826 ;; than necessary; but all the
827 ;; alternatives seem to have their own
828 ;; efficiency problems.
832 (return (values i index))))))
834 (def %find-position-if when)
835 (def %find-position-if-not unless))
837 ;;; %FIND-POSITION for LIST data can be expanded into %FIND-POSITION-IF
838 ;;; without loss of efficiency. (I.e., the optimizer should be able
839 ;;; to straighten everything out.)
840 (deftransform %find-position ((item sequence from-end start end key test)
843 :policy (> speed space)
846 '(%find-position-if (let ((test-fun (%coerce-callable-to-fun test)))
847 ;; The order of arguments for asymmetric tests
848 ;; (e.g. #'<, as opposed to order-independent
849 ;; tests like #'=) is specified in the spec
850 ;; section 17.2.1 -- the O/Zi stuff there.
852 (funcall test-fun item i)))
857 (%coerce-callable-to-fun key)))
859 ;;; The inline expansions for the VECTOR case are saved as macros so
860 ;;; that we can share them between the DEFTRANSFORMs and the default
861 ;;; cases in the DEFUNs. (This isn't needed for the LIST case, because
862 ;;; the DEFTRANSFORMs for LIST are less choosy about when to expand.)
863 (defun %find-position-or-find-position-if-vector-expansion (sequence-arg
869 (with-unique-names (offset block index n-sequence sequence n-end end)
870 `(let ((,n-sequence ,sequence-arg)
872 (with-array-data ((,sequence ,n-sequence :offset-var ,offset)
874 (,end (%check-vector-sequence-bounds
875 ,n-sequence ,start ,n-end)))
877 (macrolet ((maybe-return ()
878 '(let ((,element (aref ,sequence ,index)))
882 (- ,index ,offset)))))))
885 ;; (If we aren't fastidious about declaring that
886 ;; INDEX might be -1, then (FIND 1 #() :FROM-END T)
887 ;; can send us off into never-never land, since
888 ;; INDEX is initialized to -1.)
889 of-type index-or-minus-1
890 from (1- ,end) downto ,start do
892 (loop for ,index of-type index from ,start below ,end do
894 (values nil nil))))))
896 (def!macro %find-position-vector-macro (item sequence
897 from-end start end key test)
898 (with-unique-names (element)
899 (%find-position-or-find-position-if-vector-expansion
905 ;; (See the LIST transform for a discussion of the correct
906 ;; argument order, i.e. whether the searched-for ,ITEM goes before
907 ;; or after the checked sequence element.)
908 `(funcall ,test ,item (funcall ,key ,element)))))
910 (def!macro %find-position-if-vector-macro (predicate sequence
911 from-end start end key)
912 (with-unique-names (element)
913 (%find-position-or-find-position-if-vector-expansion
919 `(funcall ,predicate (funcall ,key ,element)))))
921 (def!macro %find-position-if-not-vector-macro (predicate sequence
922 from-end start end key)
923 (with-unique-names (element)
924 (%find-position-or-find-position-if-vector-expansion
930 `(not (funcall ,predicate (funcall ,key ,element))))))
932 ;;; %FIND-POSITION, %FIND-POSITION-IF and %FIND-POSITION-IF-NOT for
934 (deftransform %find-position-if ((predicate sequence from-end start end key)
935 (function vector t t t function)
937 :policy (> speed space)
940 (check-inlineability-of-find-position-if sequence from-end)
941 '(%find-position-if-vector-macro predicate sequence
942 from-end start end key))
944 (deftransform %find-position-if-not ((predicate sequence from-end start end key)
945 (function vector t t t function)
947 :policy (> speed space)
950 (check-inlineability-of-find-position-if sequence from-end)
951 '(%find-position-if-not-vector-macro predicate sequence
952 from-end start end key))
954 (deftransform %find-position ((item sequence from-end start end key test)
955 (t vector t t t function function)
957 :policy (> speed space)
960 (check-inlineability-of-find-position-if sequence from-end)
961 '(%find-position-vector-macro item sequence
962 from-end start end key test))
964 ;;; logic to unravel :TEST, :TEST-NOT, and :KEY options in FIND,
965 ;;; POSITION-IF, etc.
966 (define-source-transform effective-find-position-test (test test-not)
967 (once-only ((test test)
970 ((and ,test ,test-not)
971 (error "can't specify both :TEST and :TEST-NOT"))
972 (,test (%coerce-callable-to-fun ,test))
974 ;; (Without DYNAMIC-EXTENT, this is potentially horribly
975 ;; inefficient, but since the TEST-NOT option is deprecated
976 ;; anyway, we don't care.)
977 (complement (%coerce-callable-to-fun ,test-not)))
979 (define-source-transform effective-find-position-key (key)
980 (once-only ((key key))
982 (%coerce-callable-to-fun ,key)
985 (macrolet ((define-find-position (fun-name values-index)
986 `(deftransform ,fun-name ((item sequence &key
987 from-end (start 0) end
989 '(nth-value ,values-index
990 (%find-position item sequence
993 (effective-find-position-key key)
994 (effective-find-position-test
996 (define-find-position find 0)
997 (define-find-position position 1))
999 (macrolet ((define-find-position-if (fun-name values-index)
1000 `(deftransform ,fun-name ((predicate sequence &key
1005 (%find-position-if (%coerce-callable-to-fun predicate)
1008 (effective-find-position-key key))))))
1009 (define-find-position-if find-if 0)
1010 (define-find-position-if position-if 1))
1012 ;;; the deprecated functions FIND-IF-NOT and POSITION-IF-NOT. We
1013 ;;; didn't bother to worry about optimizing them, except note that on
1014 ;;; Sat, Oct 06, 2001 at 04:22:38PM +0100, Christophe Rhodes wrote on
1017 ;;; My understanding is that while the :test-not argument is
1018 ;;; deprecated in favour of :test (complement #'foo) because of
1019 ;;; semantic difficulties (what happens if both :test and :test-not
1020 ;;; are supplied, etc) the -if-not variants, while officially
1021 ;;; deprecated, would be undeprecated were X3J13 actually to produce
1022 ;;; a revised standard, as there are perfectly legitimate idiomatic
1023 ;;; reasons for allowing the -if-not versions equal status,
1024 ;;; particularly remove-if-not (== filter).
1026 ;;; This is only an informal understanding, I grant you, but
1027 ;;; perhaps it's worth optimizing the -if-not versions in the same
1028 ;;; way as the others?
1030 ;;; FIXME: Maybe remove uses of these deprecated functions (and
1031 ;;; definitely of :TEST-NOT) within the implementation of SBCL.
1032 (macrolet ((define-find-position-if-not (fun-name values-index)
1033 `(deftransform ,fun-name ((predicate sequence &key
1038 (%find-position-if-not (%coerce-callable-to-fun predicate)
1041 (effective-find-position-key key))))))
1042 (define-find-position-if-not find-if-not 0)
1043 (define-find-position-if-not position-if-not 1))