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 ((call `(funcall ,fn . ,(args-to-fn)))
30 (endtest `(or ,@(tests))))
34 (map-result (gensym)))
35 `(let ((,map-result (list nil)))
36 (do-anonymous ((,temp ,map-result) . ,(do-clauses))
37 (,endtest (cdr ,map-result))
38 (setq ,temp (last (nconc ,temp ,call)))))))
41 (map-result (gensym)))
42 `(let ((,map-result (list nil)))
43 (do-anonymous ((,temp ,map-result) . ,(do-clauses))
44 (,endtest (cdr ,map-result))
45 (rplacd ,temp (setq ,temp (list ,call)))))))
47 `(let ((,n-first ,(first arglists)))
48 (do-anonymous ,(do-clauses)
49 (,endtest ,n-first) ,call))))))))
51 (define-source-transform mapc (function list &rest more-lists)
52 (mapfoo-transform function (cons list more-lists) nil t))
54 (define-source-transform mapcar (function list &rest more-lists)
55 (mapfoo-transform function (cons list more-lists) :list t))
57 (define-source-transform mapcan (function list &rest more-lists)
58 (mapfoo-transform function (cons list more-lists) :nconc t))
60 (define-source-transform mapl (function list &rest more-lists)
61 (mapfoo-transform function (cons list more-lists) nil nil))
63 (define-source-transform maplist (function list &rest more-lists)
64 (mapfoo-transform function (cons list more-lists) :list nil))
66 (define-source-transform mapcon (function list &rest more-lists)
67 (mapfoo-transform function (cons list more-lists) :nconc nil))
69 ;;;; mapping onto sequences: the MAP function
71 ;;; MAP is %MAP plus a check to make sure that any length specified in
72 ;;; the result type matches the actual result. We also wrap it in a
73 ;;; TRULY-THE for the most specific type we can determine.
74 (deftransform map ((result-type-arg fun &rest seqs) * * :node node)
75 (let* ((seq-names (make-gensym-list (length seqs)))
76 (bare `(%map result-type-arg fun ,@seq-names))
77 (constant-result-type-arg-p (constant-continuation-p result-type-arg))
78 ;; what we know about the type of the result. (Note that the
79 ;; "result type" argument is not necessarily the type of the
80 ;; result, since NIL means the result has NULL type.)
81 (result-type (if (not constant-result-type-arg-p)
83 (let ((result-type-arg-value
84 (continuation-value result-type-arg)))
85 (if (null result-type-arg-value)
87 result-type-arg-value)))))
88 `(lambda (result-type-arg fun ,@seq-names)
89 (truly-the ,result-type
90 ,(cond ((policy node (< safety 3))
91 ;; ANSI requires the length-related type check only
92 ;; when the SAFETY quality is 3... in other cases, we
95 ((not constant-result-type-arg-p)
96 `(sequence-of-checked-length-given-type ,bare
99 (let ((result-ctype (ir1-transform-specifier-type result-type)))
100 (if (array-type-p result-ctype)
101 (let ((dims (array-type-dimensions result-ctype)))
102 (unless (and (listp dims) (= (length dims) 1))
103 (give-up-ir1-transform "invalid sequence type"))
104 (let ((dim (first dims)))
107 `(vector-of-checked-length-given-length ,bare
109 ;; FIXME: this is wrong, as not all subtypes of
110 ;; VECTOR are ARRAY-TYPEs [consider, for
111 ;; example, (OR (VECTOR T 3) (VECTOR T
112 ;; 4))]. However, it's difficult to see what we
113 ;; should put here... maybe we should
114 ;; GIVE-UP-IR1-TRANSFORM if the type is a
115 ;; subtype of VECTOR but not an ARRAY-TYPE?
118 ;;; Try to compile %MAP efficiently when we can determine sequence
119 ;;; argument types at compile time.
121 ;;; Note: This transform was written to allow open coding of
122 ;;; quantifiers by expressing them in terms of (MAP NIL ..). For
123 ;;; non-NIL values of RESULT-TYPE, it's still useful, but not
124 ;;; necessarily as efficient as possible. In particular, it will be
125 ;;; inefficient when RESULT-TYPE is a SIMPLE-ARRAY with specialized
126 ;;; numeric element types. It should be straightforward to make it
127 ;;; handle that case more efficiently, but it's left as an exercise to
128 ;;; the reader, because the code is complicated enough already and I
129 ;;; don't happen to need that functionality right now. -- WHN 20000410
130 (deftransform %map ((result-type fun &rest seqs) * * :policy (>= speed space))
132 (unless seqs (abort-ir1-transform "no sequence args"))
133 (unless (constant-continuation-p result-type)
134 (give-up-ir1-transform "RESULT-TYPE argument not constant"))
135 (labels (;; 1-valued SUBTYPEP, fails unless second value of SUBTYPEP is true
136 (fn-1subtypep (fn x y)
137 (multiple-value-bind (subtype-p valid-p) (funcall fn x y)
140 (give-up-ir1-transform
141 "can't analyze sequence type relationship"))))
142 (1subtypep (x y) (fn-1subtypep #'sb!xc:subtypep x y))
143 (1csubtypep (x y) (fn-1subtypep #'csubtypep x y))
145 (let ((ctype (continuation-type seq)))
146 (cond ((1csubtypep ctype (specifier-type 'vector)) 'vector)
147 ((1csubtypep ctype (specifier-type 'list)) 'list)
149 (give-up-ir1-transform
150 "can't determine sequence argument type"))))))
151 (let* ((result-type-value (continuation-value result-type))
152 (result-supertype (cond ((null result-type-value) 'null)
153 ((1subtypep result-type-value 'vector)
155 ((1subtypep result-type-value 'list)
158 (give-up-ir1-transform
159 "can't determine result type"))))
160 (seq-supertypes (mapcar #'seq-supertype seqs)))
161 (cond ((and result-type-value (= 1 (length seqs)))
162 ;; The consing arity-1 cases can be implemented
163 ;; reasonably efficiently as function calls, and the cost
164 ;; of consing should be significantly larger than
165 ;; function call overhead, so we always compile these
166 ;; cases as full calls regardless of speed-versus-space
167 ;; optimization policy.
168 (cond ((subtypep 'list result-type-value)
169 '(apply #'%map-to-list-arity-1 fun seqs))
170 (;; (This one can be inefficient due to COERCE, but
171 ;; the current open-coded implementation has the
173 (subtypep result-type-value 'vector)
174 `(coerce (apply #'%map-to-simple-vector-arity-1 fun seqs)
175 ',result-type-value))
176 (t (bug "impossible (?) sequence type"))))
178 (let* ((seq-args (make-gensym-list (length seqs)))
180 (mapcar (lambda (seq-arg seq-supertype)
181 (let ((i (gensym "I")))
183 (vector `(,i 0 (1+ ,i)))
184 (list `(,i ,seq-arg (rest ,i))))))
185 seq-args seq-supertypes))
186 (indices (mapcar #'first index-bindingoids))
187 (index-decls (mapcar (lambda (index seq-supertype)
188 `(type ,(ecase seq-supertype
192 indices seq-supertypes))
193 (tests (mapcar (lambda (seq-arg seq-supertype index)
195 (vector `(>= ,index (length ,seq-arg)))
196 (list `(endp ,index))))
197 seq-args seq-supertypes indices))
198 (values (mapcar (lambda (seq-arg seq-supertype index)
200 (vector `(aref ,seq-arg ,index))
201 (list `(first ,index))))
202 seq-args seq-supertypes indices)))
203 (multiple-value-bind (push-dacc final-result)
204 (ecase result-supertype
205 (null (values nil nil))
206 (list (values `(push dacc acc) `(nreverse acc)))
207 (vector (values `(push dacc acc)
208 `(coerce (nreverse acc)
209 ',result-type-value))))
210 ;; (We use the same idiom, of returning a LAMBDA from
211 ;; DEFTRANSFORM, as is used in the DEFTRANSFORMs for
212 ;; FUNCALL and ALIEN-FUNCALL, and for the same
213 ;; reason: we need to get the runtime values of each
214 ;; of the &REST vars.)
215 `(lambda (result-type fun ,@seq-args)
216 (declare (ignore result-type))
217 (do ((really-fun (%coerce-callable-to-fun fun))
222 (declare ,@index-decls)
223 (declare (type list acc))
224 (declare (ignorable acc))
225 (let ((dacc (funcall really-fun ,@values)))
226 (declare (ignorable dacc))
229 (deftransform elt ((s i) ((simple-array * (*)) *) *)
232 (deftransform elt ((s i) (list *) *)
235 (deftransform %setelt ((s i v) ((simple-array * (*)) * *) *)
238 (deftransform %setelt ((s i v) (list * *))
239 '(setf (car (nthcdr i s)) v))
241 (macrolet ((def (name)
242 `(deftransform ,name ((e l &key (test #'eql)) * *
244 (unless (constant-continuation-p l)
245 (give-up-ir1-transform))
247 (let ((val (continuation-value l)))
250 (and (>= speed space)
251 (<= (length val) 5))))
252 (give-up-ir1-transform))
256 `(if (funcall test e ',(car els))
264 ;;; FIXME: We have rewritten the original code that used DOLIST to this
265 ;;; more natural MACROLET. However, the original code suggested that when
266 ;;; this was done, a few bytes could be saved by a call to a shared
267 ;;; function. This remains to be done.
268 (macrolet ((def (fun eq-fun)
269 `(deftransform ,fun ((item list &key test) (t list &rest t) *)
271 ;; FIXME: The scope of this transformation could be
272 ;; widened somewhat, letting it work whenever the test is
273 ;; 'EQL and we know from the type of ITEM that it #'EQ
274 ;; works like #'EQL on it. (E.g. types FIXNUM, CHARACTER,
276 ;; If TEST is EQ, apply transform, else
277 ;; if test is not EQL, then give up on transform, else
278 ;; if ITEM is not a NUMBER or is a FIXNUM, apply
279 ;; transform, else give up on transform.
281 (unless (continuation-fun-is test '(eq))
282 (give-up-ir1-transform)))
283 ((types-equal-or-intersect (continuation-type item)
284 (specifier-type 'number))
285 (give-up-ir1-transform "Item might be a number.")))
286 `(,',eq-fun item list))))
291 (deftransform delete-if ((pred list) (t list))
293 '(do ((x list (cdr x))
296 (cond ((funcall pred (car x))
299 (rplacd splice (cdr x))))
300 (T (setq splice x)))))
302 (deftransform fill ((seq item &key (start 0) (end (length seq)))
303 (vector t &key (:start t) (:end index))
305 :policy (> speed space))
307 (let ((element-type (upgraded-element-type-specifier-or-give-up seq)))
309 `(with-array-data ((data seq)
312 (declare (type (simple-array ,element-type 1) data))
313 (declare (type fixnum start end))
314 (do ((i start (1+ i)))
316 (declare (type index i))
317 ;; WITH-ARRAY-DATA did our range checks once and for all, so
318 ;; it'd be wasteful to check again on every AREF...
319 (declare (optimize (safety 0)))
320 (setf (aref data i) item)))
321 ;; ... though we still need to check that the new element can fit
322 ;; into the vector in safe code. -- CSR, 2002-07-05
323 `((declare (type ,element-type item))))))
327 ;;; Return true if CONT's only use is a non-NOTINLINE reference to a
328 ;;; global function with one of the specified NAMES.
329 (defun continuation-fun-is (cont names)
330 (declare (type continuation cont) (list names))
331 (let ((use (continuation-use cont)))
333 (let ((leaf (ref-leaf use)))
334 (and (global-var-p leaf)
335 (eq (global-var-kind leaf) :global-function)
336 (not (null (member (leaf-source-name leaf) names
337 :test #'equal))))))))
339 ;;; If CONT is a constant continuation, the return the constant value.
340 ;;; If it is null, then return default, otherwise quietly give up the
343 ;;; ### Probably should take an ARG and flame using the NAME.
344 (defun constant-value-or-lose (cont &optional default)
345 (declare (type (or continuation null) cont))
346 (cond ((not cont) default)
347 ((constant-continuation-p cont)
348 (continuation-value cont))
350 (give-up-ir1-transform))))
352 ;;; FIXME: Why is this code commented out? (Why *was* it commented
353 ;;; out? We inherited this situation from cmucl-2.4.8, with no
354 ;;; explanation.) Should we just delete this code?
356 ;;; This is a frob whose job it is to make it easier to pass around
357 ;;; the arguments to IR1 transforms. It bundles together the name of
358 ;;; the argument (which should be referenced in any expansion), and
359 ;;; the continuation for that argument (or NIL if unsupplied.)
360 (defstruct (arg (:constructor %make-arg (name cont))
362 (name nil :type symbol)
363 (cont nil :type (or continuation null)))
364 (defmacro make-arg (name)
365 `(%make-arg ',name ,name))
367 ;;; If Arg is null or its CONT is null, then return Default, otherwise
368 ;;; return Arg's NAME.
369 (defun default-arg (arg default)
370 (declare (type (or arg null) arg))
371 (if (and arg (arg-cont arg))
375 ;;; If Arg is null or has no CONT, return the default. Otherwise, Arg's
376 ;;; CONT must be a constant continuation whose value we return. If not, we
378 (defun arg-constant-value (arg default)
379 (declare (type (or arg null) arg))
380 (if (and arg (arg-cont arg))
381 (let ((cont (arg-cont arg)))
382 (unless (constant-continuation-p cont)
383 (give-up-ir1-transform "Argument is not constant: ~S."
385 (continuation-value from-end))
388 ;;; If Arg is a constant and is EQL to X, then return T, otherwise NIL. If
389 ;;; Arg is NIL or its CONT is NIL, then compare to the default.
390 (defun arg-eql (arg default x)
391 (declare (type (or arg null) x))
392 (if (and arg (arg-cont arg))
393 (let ((cont (arg-cont arg)))
394 (and (constant-continuation-p cont)
395 (eql (continuation-value cont) x)))
398 (defstruct (iterator (:copier nil))
399 ;; The kind of iterator.
400 (kind nil (member :normal :result))
401 ;; A list of LET* bindings to create the initial state.
402 (binds nil :type list)
403 ;; A list of declarations for Binds.
404 (decls nil :type list)
405 ;; A form that returns the current value. This may be set with SETF to set
406 ;; the current value.
407 (current (error "Must specify CURRENT."))
408 ;; In a :NORMAL iterator, a form that tests whether there is a current value.
410 ;; In a :RESULT iterator, a form that truncates the result at the current
411 ;; position and returns it.
413 ;; A form that returns the initial total number of values. The result is
414 ;; undefined after NEXT has been evaluated.
415 (length (error "Must specify LENGTH."))
416 ;; A form that advances the state to the next value. It is an error to call
417 ;; this when the iterator is Done.
418 (next (error "Must specify NEXT.")))
420 ;;; Type of an index var that can go negative (in the from-end case.)
421 (deftype neg-index ()
422 `(integer -1 ,most-positive-fixnum))
424 ;;; Return an ITERATOR structure describing how to iterate over an arbitrary
425 ;;; sequence. Sequence is a variable bound to the sequence, and Type is the
426 ;;; type of the sequence. If true, INDEX is a variable that should be bound to
427 ;;; the index of the current element in the sequence.
429 ;;; If we can't tell whether the sequence is a list or a vector, or whether
430 ;;; the iteration is forward or backward, then GIVE-UP.
431 (defun make-sequence-iterator (sequence type &key start end from-end index)
432 (declare (symbol sequence) (type ctype type)
433 (type (or arg null) start end from-end)
434 (type (or symbol null) index))
435 (let ((from-end (arg-constant-value from-end nil)))
436 (cond ((csubtypep type (specifier-type 'vector))
437 (let* ((n-stop (gensym))
438 (n-idx (or index (gensym)))
439 (start (default-arg 0 start))
440 (end (default-arg `(length ,sequence) end)))
443 :binds `((,n-idx ,(if from-end `(1- ,end) ,start))
444 (,n-stop ,(if from-end `(1- ,start) ,end)))
445 :decls `((type neg-index ,n-idx ,n-stop))
446 :current `(aref ,sequence ,n-idx)
447 :done `(,(if from-end '<= '>=) ,n-idx ,n-stop)
449 ,(if from-end `(1- ,n-idx) `(1+ ,n-idx)))
452 `(- ,n-stop ,n-idx)))))
453 ((csubtypep type (specifier-type 'list))
454 (let* ((n-stop (if (and end (not from-end)) (gensym) nil))
456 (start-p (not (arg-eql start 0 0)))
457 (end-p (not (arg-eql end nil nil)))
458 (start (default-arg start 0))
459 (end (default-arg end nil)))
463 (if (or start-p end-p)
464 `(nreverse (subseq ,sequence ,start
465 ,@(when end `(,end))))
466 `(reverse ,sequence))
468 `(nthcdr ,start ,sequence)
471 `((,n-stop (nthcdr (the index
475 `((,index ,(if from-end `(1- ,end) start)))))
477 :decls `((list ,n-current ,n-end)
478 ,@(when index `((type neg-index ,index))))
479 :current `(car ,n-current)
480 :done `(eq ,n-current ,n-stop)
481 :length `(- ,(or end `(length ,sequence)) ,start)
483 (setq ,n-current (cdr ,n-current))
490 (give-up-ir1-transform
491 "can't tell whether sequence is a list or a vector")))))
493 ;;; Make an iterator used for constructing result sequences. Name is a
494 ;;; variable to be bound to the result sequence. Type is the type of result
495 ;;; sequence to make. Length is an expression to be evaluated to get the
496 ;;; maximum length of the result (not evaluated in list case.)
497 (defun make-result-sequence-iterator (name type length)
498 (declare (symbol name) (type ctype type))
500 ;;; Define each NAME as a local macro that will call the value of the
501 ;;; function arg with the given arguments. If the argument isn't known to be a
502 ;;; function, give them an efficiency note and reference a coerced version.
503 (defmacro coerce-funs (specs &body body)
505 "COERCE-FUNCTIONS ({(Name Fun-Arg Default)}*) Form*"
509 `(let ((body (progn ,@body))
510 (n-fun (arg-name ,(second spec)))
511 (fun-cont (arg-cont ,(second spec))))
512 (cond ((not fun-cont)
513 `(macrolet ((,',(first spec) (&rest args)
514 `(,',',(third spec) ,@args)))
516 ((not (csubtypep (continuation-type fun-cont)
517 (specifier-type 'function)))
518 (when (policy *compiler-error-context*
519 (> speed inhibit-warnings))
521 "~S may not be a function, so must coerce at run-time."
523 (once-only ((n-fun `(if (functionp ,n-fun)
525 (symbol-function ,n-fun))))
526 `(macrolet ((,',(first spec) (&rest args)
527 `(funcall ,',n-fun ,@args)))
530 `(macrolet ((,',(first spec) (&rest args)
531 `(funcall ,',n-fun ,@args)))
534 ;;; Wrap code around the result of the body to define Name as a local macro
535 ;;; that returns true when its arguments satisfy the test according to the Args
536 ;;; Test and Test-Not. If both Test and Test-Not are supplied, abort the
538 (defmacro with-sequence-test ((name test test-not) &body body)
539 `(let ((not-p (arg-cont ,test-not)))
540 (when (and (arg-cont ,test) not-p)
541 (abort-ir1-transform "Both ~S and ~S were supplied."
543 (arg-name ,test-not)))
544 (coerce-funs ((,name (if not-p ,test-not ,test) eql))
548 ;;;; hairy sequence transforms
550 ;;; FIXME: no hairy sequence transforms in SBCL?
552 ;;;; string operations
554 ;;; We transform the case-sensitive string predicates into a non-keyword
555 ;;; version. This is an IR1 transform so that we don't have to worry about
556 ;;; changing the order of evaluation.
557 (macrolet ((def (fun pred*)
558 `(deftransform ,fun ((string1 string2 &key (start1 0) end1
561 `(,',pred* string1 string2 start1 end1 start2 end2))))
562 (def string< string<*)
563 (def string> string>*)
564 (def string<= string<=*)
565 (def string>= string>=*)
566 (def string= string=*)
567 (def string/= string/=*))
569 ;;; Return a form that tests the free variables STRING1 and STRING2
570 ;;; for the ordering relationship specified by LESSP and EQUALP. The
571 ;;; start and end are also gotten from the environment. Both strings
572 ;;; must be SIMPLE-STRINGs.
573 (macrolet ((def (name lessp equalp)
574 `(deftransform ,name ((string1 string2 start1 end1 start2 end2)
575 (simple-string simple-string t t t t) *)
576 `(let* ((end1 (if (not end1) (length string1) end1))
577 (end2 (if (not end2) (length string2) end2))
578 (index (sb!impl::%sp-string-compare
579 string1 start1 end1 string2 start2 end2)))
581 (cond ((= index ,(if ',lessp 'end1 'end2)) index)
582 ((= index ,(if ',lessp 'end2 'end1)) nil)
583 ((,(if ',lessp 'char< 'char>)
584 (schar string1 index)
593 ,(if ',equalp 'end1 nil))))))
596 (def string>* nil nil)
597 (def string>=* nil t))
599 (macrolet ((def (name result-fun)
600 `(deftransform ,name ((string1 string2 start1 end1 start2 end2)
601 (simple-string simple-string t t t t) *)
603 (sb!impl::%sp-string-compare
604 string1 start1 (or end1 (length string1))
605 string2 start2 (or end2 (length string2)))))))
607 (def string/=* identity))
610 ;;;; string-only transforms for sequence functions
612 ;;;; Note: CMU CL had more of these, including transforms for
613 ;;;; functions which cons. In SBCL, we've gotten rid of most of the
614 ;;;; transforms for functions which cons, since our GC overhead is
615 ;;;; sufficiently large that it doesn't seem worth it to try to
616 ;;;; economize on function call overhead or on the overhead of runtime
617 ;;;; type dispatch in AREF. The exception is CONCATENATE, since
618 ;;;; a full call to CONCATENATE would have to look up the sequence
619 ;;;; type, which can be really slow.
621 ;;;; FIXME: It would be nicer for these transforms to work for any
622 ;;;; calls when all arguments are vectors with the same element type,
623 ;;;; rather than restricting them to STRINGs only.
625 ;;; Moved here from generic/vm-tran.lisp to satisfy clisp
627 ;;; FIXME: It would be good to implement SB!XC:DEFCONSTANT, and use
628 ;;; use that here, so that the compiler is born knowing this value.
629 ;;; FIXME: Add a comment telling whether this holds for all vectors
630 ;;; or only for vectors based on simple arrays (non-adjustable, etc.).
631 (def!constant vector-data-bit-offset
632 (* sb!vm:vector-data-offset sb!vm:n-word-bits))
634 ;;; FIXME: Shouldn't we be testing for legality of
635 ;;; * START1, START2, END1, and END2 indices?
636 ;;; * size of copied string relative to destination string?
637 ;;; (Either there should be tests conditional on SAFETY>=SPEED, or
638 ;;; the transform should be conditional on SPEED>SAFETY.)
640 ;;; FIXME: Also, the transform should probably be dependent on
642 (deftransform replace ((string1 string2 &key (start1 0) (start2 0)
644 (simple-string simple-string &rest t))
646 (declare (optimize (safety 0)))
647 (bit-bash-copy string2
649 (+ (the index (* start2 sb!vm:n-byte-bits))
650 ,vector-data-bit-offset))
653 (+ (the index (* start1 sb!vm:n-byte-bits))
654 ,vector-data-bit-offset))
656 (* (min (the index (- (or end1 (length string1))
658 (the index (- (or end2 (length string2))
663 ;;; FIXME: It seems as though it should be possible to make a DEFUN
664 ;;; %CONCATENATE (with a DEFTRANSFORM to translate constant RTYPE to
665 ;;; CTYPE before calling %CONCATENATE) which is comparably efficient,
666 ;;; at least once DYNAMIC-EXTENT works.
668 ;;; FIXME: currently KLUDGEed because of bug 188
669 (deftransform concatenate ((rtype &rest sequences)
670 (t &rest simple-string)
672 :policy (< safety 3))
677 (dolist (seq sequences)
678 (declare (ignorable seq))
679 (let ((n-seq (gensym))
682 (lets `(,n-length (the index (* (length ,n-seq) sb!vm:n-byte-bits))))
683 (all-lengths n-length)
684 (forms `(bit-bash-copy ,n-seq ,vector-data-bit-offset
687 (forms `(setq start (opaque-identity (+ start ,n-length))))))
688 `(lambda (rtype ,@(args))
689 (declare (ignore rtype))
691 (flet ((opaque-identity (x) x))
692 (declare (notinline opaque-identity))
694 (res (make-string (truncate (the index (+ ,@(all-lengths)))
696 (start ,vector-data-bit-offset))
697 (declare (type index start ,@(all-lengths)))
701 ;;;; CONS accessor DERIVE-TYPE optimizers
703 (defoptimizer (car derive-type) ((cons))
704 (let ((type (continuation-type cons))
705 (null-type (specifier-type 'null)))
706 (cond ((eq type null-type)
709 (cons-type-car-type type)))))
711 (defoptimizer (cdr derive-type) ((cons))
712 (let ((type (continuation-type cons))
713 (null-type (specifier-type 'null)))
714 (cond ((eq type null-type)
717 (cons-type-cdr-type type)))))
719 ;;;; FIND, POSITION, and their -IF and -IF-NOT variants
721 ;;; We want to make sure that %FIND-POSITION is inline-expanded into
722 ;;; %FIND-POSITION-IF only when %FIND-POSITION-IF has an inline
723 ;;; expansion, so we factor out the condition into this function.
724 (defun check-inlineability-of-find-position-if (sequence from-end)
725 (let ((ctype (continuation-type sequence)))
726 (cond ((csubtypep ctype (specifier-type 'vector))
727 ;; It's not worth trying to inline vector code unless we
728 ;; know a fair amount about it at compile time.
729 (upgraded-element-type-specifier-or-give-up sequence)
730 (unless (constant-continuation-p from-end)
731 (give-up-ir1-transform
732 "FROM-END argument value not known at compile time")))
733 ((csubtypep ctype (specifier-type 'list))
734 ;; Inlining on lists is generally worthwhile.
737 (give-up-ir1-transform
738 "sequence type not known at compile time")))))
740 ;;; %FIND-POSITION-IF and %FIND-POSITION-IF-NOT for LIST data
741 (macrolet ((def (name condition)
742 `(deftransform ,name ((predicate sequence from-end start end key)
743 (function list t t t function)
745 :policy (> speed space)
751 (declare (type index index))
752 (dolist (i sequence (values find position))
753 (let ((key-i (funcall key i)))
754 (when (and end (>= index end))
755 (return (values find position)))
756 (when (>= index start)
757 (,',condition (funcall predicate key-i)
758 ;; This hack of dealing with non-NIL
759 ;; FROM-END for list data by iterating
760 ;; forward through the list and keeping
761 ;; track of the last time we found a match
762 ;; might be more screwy than what the user
763 ;; expects, but it seems to be allowed by
764 ;; the ANSI standard. (And if the user is
765 ;; screwy enough to ask for FROM-END
766 ;; behavior on list data, turnabout is
769 ;; It's also not enormously efficient,
770 ;; calling PREDICATE and KEY more often
771 ;; than necessary; but all the
772 ;; alternatives seem to have their own
773 ;; efficiency problems.
777 (return (values i index))))))
779 (def %find-position-if when)
780 (def %find-position-if-not unless))
782 ;;; %FIND-POSITION for LIST data can be expanded into %FIND-POSITION-IF
783 ;;; without loss of efficiency. (I.e., the optimizer should be able
784 ;;; to straighten everything out.)
785 (deftransform %find-position ((item sequence from-end start end key test)
788 :policy (> speed space)
791 '(%find-position-if (let ((test-fun (%coerce-callable-to-fun test)))
792 ;; I'm having difficulty believing I'm
793 ;; reading it right, but as far as I can see,
794 ;; the only guidance that ANSI gives for the
795 ;; order of arguments to asymmetric tests is
796 ;; the character-set dependent example from
797 ;; the definition of FIND,
798 ;; (find #\d "here are some.." :test #'char>)
800 ;; (In ASCII, we have (CHAR> #\d #\SPACE)=>T.)
801 ;; (Neither the POSITION definition page nor
802 ;; section 17.2 ("Rules about Test Functions")
803 ;; seem to consider the possibility of
806 ;; So, judging from the example, we want to
807 ;; do (FUNCALL TEST-FUN ITEM I), because
808 ;; (FUNCALL #'CHAR> #\d #\SPACE)=>T.
810 ;; -- WHN (whose attention was drawn to it by
811 ;; Alexey Dejneka's bug report/fix)
813 (funcall test-fun item i)))
818 (%coerce-callable-to-fun key)))
820 ;;; The inline expansions for the VECTOR case are saved as macros so
821 ;;; that we can share them between the DEFTRANSFORMs and the default
822 ;;; cases in the DEFUNs. (This isn't needed for the LIST case, because
823 ;;; the DEFTRANSFORMs for LIST are less choosy about when to expand.)
824 (defun %find-position-or-find-position-if-vector-expansion (sequence-arg
830 (let ((offset (gensym "OFFSET"))
831 (block (gensym "BLOCK"))
832 (index (gensym "INDEX"))
833 (n-sequence (gensym "N-SEQUENCE-"))
834 (sequence (gensym "SEQUENCE"))
835 (n-end (gensym "N-END-"))
836 (end (gensym "END-")))
837 `(let ((,n-sequence ,sequence-arg)
839 (with-array-data ((,sequence ,n-sequence :offset-var ,offset)
841 (,end (or ,n-end (length ,n-sequence))))
843 (macrolet ((maybe-return ()
844 '(let ((,element (aref ,sequence ,index)))
848 (- ,index ,offset)))))))
851 ;; (If we aren't fastidious about declaring that
852 ;; INDEX might be -1, then (FIND 1 #() :FROM-END T)
853 ;; can send us off into never-never land, since
854 ;; INDEX is initialized to -1.)
855 of-type index-or-minus-1
856 from (1- ,end) downto ,start do
858 (loop for ,index of-type index from ,start below ,end do
860 (values nil nil))))))
862 (def!macro %find-position-vector-macro (item sequence
863 from-end start end key test)
864 (let ((element (gensym "ELEMENT")))
865 (%find-position-or-find-position-if-vector-expansion
871 ;; (See the LIST transform for a discussion of the correct
872 ;; argument order, i.e. whether the searched-for ,ITEM goes before
873 ;; or after the checked sequence element.)
874 `(funcall ,test ,item (funcall ,key ,element)))))
876 (def!macro %find-position-if-vector-macro (predicate sequence
877 from-end start end key)
878 (let ((element (gensym "ELEMENT")))
879 (%find-position-or-find-position-if-vector-expansion
885 `(funcall ,predicate (funcall ,key ,element)))))
887 (def!macro %find-position-if-not-vector-macro (predicate sequence
888 from-end start end key)
889 (let ((element (gensym "ELEMENT")))
890 (%find-position-or-find-position-if-vector-expansion
896 `(not (funcall ,predicate (funcall ,key ,element))))))
898 ;;; %FIND-POSITION, %FIND-POSITION-IF and %FIND-POSITION-IF-NOT for
900 (deftransform %find-position-if ((predicate sequence from-end start end key)
901 (function vector t t t function)
903 :policy (> speed space)
906 (check-inlineability-of-find-position-if sequence from-end)
907 '(%find-position-if-vector-macro predicate sequence
908 from-end start end key))
910 (deftransform %find-position-if-not ((predicate sequence from-end start end key)
911 (function vector t t t function)
913 :policy (> speed space)
916 (check-inlineability-of-find-position-if sequence from-end)
917 '(%find-position-if-not-vector-macro predicate sequence
918 from-end start end key))
920 (deftransform %find-position ((item sequence from-end start end key test)
921 (t vector t t t function function)
923 :policy (> speed space)
926 (check-inlineability-of-find-position-if sequence from-end)
927 '(%find-position-vector-macro item sequence
928 from-end start end key test))