1 ;;;; that part of the implementation of HASH-TABLE which lives solely
2 ;;;; on the target system, not on the cross-compilation host
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.
13 (in-package "SB!IMPL")
17 ;; This stuff is performance critical and unwind-protect is too
18 ;; slow. And without the locking the next vector can get cyclic
19 ;; causing looping in a WITHOUT-GCING form, SHRINK-VECTOR can corrupt
20 ;; memory and who knows what else.
21 (defmacro with-spinlock-and-without-gcing ((spinlock) &body body)
23 (declare (ignore spinlock))
24 (with-unique-names (old-gc-inhibit old-interrupts-enabled)
25 `(let ((,old-gc-inhibit *gc-inhibit*)
26 (,old-interrupts-enabled *interrupts-enabled*)
27 (*interrupts-enabled* nil)
32 (sb!thread::get-spinlock ,spinlock)
35 (sb!thread::release-spinlock ,spinlock)
36 (let ((*interrupts-enabled* ,old-interrupts-enabled)
37 (*gc-inhibit* ,old-gc-inhibit))
38 ;; the test is racy, but it can err only on the overeager
40 (sb!kernel::maybe-handle-pending-gc))))))
42 (eval-when (:compile-toplevel :load-toplevel :execute)
43 (defconstant max-hash sb!xc:most-positive-fixnum))
46 `(integer 0 ,max-hash))
48 ;;; FIXME: Does this always make a nonnegative FIXNUM? If so, then
49 ;;; explain why. If not (or if the reason it always makes a
50 ;;; nonnegative FIXNUM is only the accident that pointers in supported
51 ;;; architectures happen to be in the lower half of the address
52 ;;; space), then fix it.
53 #!-sb-fluid (declaim (inline pointer-hash))
54 (defun pointer-hash (key)
55 (declare (values hash))
56 (truly-the hash (%primitive sb!c:make-fixnum key)))
58 #!-sb-fluid (declaim (inline eq-hash))
60 (declare (values hash (member t nil)))
61 (values (pointer-hash key)
62 (oddp (get-lisp-obj-address key))))
64 #!-sb-fluid (declaim (inline equal-hash))
65 (defun equal-hash (key)
66 (declare (values hash (member t nil)))
68 ;; For some types the definition of EQUAL implies a special hash
69 ((or string cons number bit-vector pathname)
70 (values (sxhash key) nil))
71 ;; Otherwise use an EQ hash, rather than SXHASH, since the values
72 ;; of SXHASH will be extremely badly distributed due to the
73 ;; requirements of the spec fitting badly with our implementation
78 #!-sb-fluid (declaim (inline eql-hash))
80 (declare (values hash (member t nil)))
85 (defun equalp-hash (key)
86 (declare (values hash (member t nil)))
87 (values (psxhash key) nil))
89 (defun almost-primify (num)
90 (declare (type index num))
92 "Return an almost prime number greater than or equal to NUM."
101 ;;;; user-defined hash table tests
103 (defvar *hash-table-tests* nil)
105 (defun define-hash-table-test (name test-fun hash-fun)
107 "Define a new kind of hash table test."
108 (declare (type symbol name)
109 (type function test-fun hash-fun))
110 (setf *hash-table-tests*
111 (cons (list name test-fun hash-fun)
112 (remove name *hash-table-tests* :test #'eq :key #'car)))
115 ;;;; construction and simple accessors
117 (defconstant +min-hash-table-size+ 16)
118 (defconstant +min-hash-table-rehash-threshold+ (float 1/16 1.0))
120 (defun make-hash-table (&key (test 'eql)
121 (size +min-hash-table-size+)
126 "Create and return a new hash table. The keywords are as follows:
127 :TEST -- Indicates what kind of test to use.
128 :SIZE -- A hint as to how many elements will be put in this hash
130 :REHASH-SIZE -- Indicates how to expand the table when it fills up.
131 If an integer, add space for that many elements. If a floating
132 point number (which must be greater than 1.0), multiply the size
134 :REHASH-THRESHOLD -- Indicates how dense the table can become before
135 forcing a rehash. Can be any positive number <=1, with density
136 approaching zero as the threshold approaches 0. Density 1 means an
137 average of one entry per bucket.
138 :WEAKNESS -- IF NIL (the default) it is a normal non-weak hash table.
139 If one of :KEY, :VALUE, :KEY-AND-VALUE, :KEY-OR-VALUE it is a weak
141 Depending on the type of weakness the lack of references to the
142 key and the value may allow for removal of the entry. If WEAKNESS
143 is :KEY and the key would otherwise be garbage the entry is eligible
144 for removal from the hash table. Similarly, if WEAKNESS is :VALUE
145 the life of an entry depends on its value's references. If WEAKNESS
146 is :KEY-AND-VALUE and either the key or the value would otherwise be
147 garbage the entry can be removed. If WEAKNESS is :KEY-OR-VALUE and
148 both the key and the value would otherwise be garbage the entry can
150 (declare (type (or function symbol) test))
151 (declare (type unsigned-byte size))
152 (multiple-value-bind (test test-fun hash-fun)
153 (cond ((or (eq test #'eq) (eq test 'eq))
154 (values 'eq #'eq #'eq-hash))
155 ((or (eq test #'eql) (eq test 'eql))
156 (values 'eql #'eql #'eql-hash))
157 ((or (eq test #'equal) (eq test 'equal))
158 (values 'equal #'equal #'equal-hash))
159 ((or (eq test #'equalp) (eq test 'equalp))
160 (values 'equalp #'equalp #'equalp-hash))
162 ;; FIXME: I'd like to remove *HASH-TABLE-TESTS* stuff.
163 ;; Failing that, I'd like to rename it to
164 ;; *USER-HASH-TABLE-TESTS*.
165 (dolist (info *hash-table-tests*
166 (error "unknown :TEST for MAKE-HASH-TABLE: ~S"
168 (destructuring-bind (test-name test-fun hash-fun) info
169 (when (or (eq test test-name) (eq test test-fun))
170 (return (values test-name test-fun hash-fun)))))))
171 (let* ((size (max +min-hash-table-size+
173 ;; SIZE is just a hint, so if the user asks
174 ;; for a SIZE which'd be too big for us to
175 ;; easily implement, we bump it down.
176 (floor array-dimension-limit 1024))))
177 (rehash-size (if (integerp rehash-size)
179 (float rehash-size 1.0)))
180 ;; FIXME: Original REHASH-THRESHOLD default should be 1.0,
181 ;; not 1, to make it easier for the compiler to avoid
183 (rehash-threshold (max +min-hash-table-rehash-threshold+
184 (float rehash-threshold 1.0)))
185 (size+1 (1+ size)) ; The first element is not usable.
186 ;; KLUDGE: The most natural way of expressing the below is
187 ;; (round (/ (float size+1) rehash-threshold)), and indeed
188 ;; it was expressed like that until 0.7.0. However,
189 ;; MAKE-HASH-TABLE is called very early in cold-init, and
190 ;; the SPARC has no primitive instructions for rounding,
191 ;; but only for truncating; therefore, we fudge this issue
192 ;; a little. The other uses of truncate, below, similarly
193 ;; used to be round. -- CSR, 2002-10-01
195 ;; Note that this has not yet been audited for
196 ;; correctness. It just seems to work. -- CSR, 2002-11-02
197 (scaled-size (truncate (/ (float size+1) rehash-threshold)))
198 (length (almost-primify (max scaled-size
199 (1+ +min-hash-table-size+))))
200 (index-vector (make-array length
202 '(unsigned-byte #.sb!vm:n-word-bits)
204 ;; Needs to be the half the length of the KV vector to link
205 ;; KV entries - mapped to indeces at 2i and 2i+1 -
207 (next-vector (make-array size+1
209 '(unsigned-byte #.sb!vm:n-word-bits)))
210 (kv-vector (make-array (* 2 size+1)
211 :initial-element +empty-ht-slot+))
212 (table (%make-hash-table
216 :rehash-size rehash-size
217 :rehash-threshold rehash-threshold
221 :index-vector index-vector
222 :next-vector next-vector
224 (unless (eq test 'eq)
226 :element-type '(unsigned-byte
228 :initial-element +magic-hash-vector-value+))
229 :spinlock (sb!thread::make-spinlock))))
230 (declare (type index size+1 scaled-size length))
231 ;; Set up the free list, all free. These lists are 0 terminated.
234 (setf (aref next-vector i) (1+ i)))
235 (setf (aref next-vector size) 0)
236 (setf (hash-table-next-free-kv table) 1)
237 (setf (hash-table-needing-rehash table) 0)
238 (setf (aref kv-vector 0) table)
241 (defun hash-table-count (hash-table)
243 "Return the number of entries in the given HASH-TABLE."
244 (declare (type hash-table hash-table)
246 (hash-table-number-entries hash-table))
249 (setf (fdocumentation 'hash-table-rehash-size 'function)
250 "Return the rehash-size HASH-TABLE was created with.")
253 (setf (fdocumentation 'hash-table-rehash-threshold 'function)
254 "Return the rehash-threshold HASH-TABLE was created with.")
256 (defun hash-table-size (hash-table)
258 "Return a size that can be used with MAKE-HASH-TABLE to create a hash
259 table that can hold however many entries HASH-TABLE can hold without
261 (hash-table-rehash-trigger hash-table))
264 (setf (fdocumentation 'hash-table-test 'function)
265 "Return the test HASH-TABLE was created with.")
268 (setf (fdocumentation 'hash-table-weakness 'function)
269 "Return the WEAKNESS of HASH-TABLE which is one of NIL, :KEY,
270 :VALUE, :KEY-AND-VALUE, :KEY-OR-VALUE.")
272 ;;;; accessing functions
274 ;;; Make new vectors for the table, extending the table based on the
276 (defun rehash (table)
277 (declare (type hash-table table))
278 (let* ((old-kv-vector (hash-table-table table))
279 (old-next-vector (hash-table-next-vector table))
280 (old-hash-vector (hash-table-hash-vector table))
281 (old-size (length old-next-vector))
283 (let ((rehash-size (hash-table-rehash-size table)))
284 (etypecase rehash-size
286 (+ rehash-size old-size))
288 (the index (truncate (* rehash-size old-size)))))))
289 (new-kv-vector (make-array (* 2 new-size)
290 :initial-element +empty-ht-slot+))
293 :element-type '(unsigned-byte #.sb!vm:n-word-bits)
296 (when old-hash-vector
298 :element-type '(unsigned-byte #.sb!vm:n-word-bits)
299 :initial-element +magic-hash-vector-value+)))
300 (old-index-vector (hash-table-index-vector table))
301 (new-length (almost-primify
302 (truncate (/ (float new-size)
303 (hash-table-rehash-threshold table)))))
305 (make-array new-length
306 :element-type '(unsigned-byte #.sb!vm:n-word-bits)
307 :initial-element 0)))
308 (declare (type index new-size new-length old-size))
310 ;; Disable GC tricks on the OLD-KV-VECTOR.
311 (set-header-data old-kv-vector sb!vm:vector-normal-subtype)
313 ;; Non-empty weak hash tables always need GC support.
314 (when (and (hash-table-weakness table) (plusp (hash-table-count table)))
315 (set-header-data new-kv-vector sb!vm:vector-valid-hashing-subtype))
317 ;; FIXME: here and in several other places in the hash table code,
318 ;; loops like this one are used when FILL or REPLACE would be
319 ;; appropriate. why are standard CL functions not used?
320 ;; Performance issues? General laziness? -- NJF, 2004-03-10
322 ;; Copy over the kv-vector. The element positions should not move
323 ;; in case there are active scans.
324 (dotimes (i (* old-size 2))
325 (declare (type index i))
326 (setf (aref new-kv-vector i) (aref old-kv-vector i)))
328 ;; Copy over the hash-vector.
329 (when old-hash-vector
330 (dotimes (i old-size)
331 (setf (aref new-hash-vector i) (aref old-hash-vector i))))
333 (setf (hash-table-next-free-kv table) 0)
334 (setf (hash-table-needing-rehash table) 0)
335 ;; Rehash all the entries; last to first so that after the pushes
336 ;; the chains are first to last.
337 (do ((i (1- new-size) (1- i)))
339 (declare (type index/2 i))
340 (let ((key (aref new-kv-vector (* 2 i)))
341 (value (aref new-kv-vector (1+ (* 2 i)))))
342 (cond ((and (eq key +empty-ht-slot+)
343 (eq value +empty-ht-slot+))
344 ;; Slot is empty, push it onto the free list.
345 (setf (aref new-next-vector i)
346 (hash-table-next-free-kv table))
347 (setf (hash-table-next-free-kv table) i))
348 ((and new-hash-vector
349 (not (= (aref new-hash-vector i)
350 +magic-hash-vector-value+)))
351 ;; Can use the existing hash value (not EQ based)
352 (let* ((hashing (aref new-hash-vector i))
353 (index (rem hashing new-length))
354 (next (aref new-index-vector index)))
355 (declare (type index index)
357 ;; Push this slot into the next chain.
358 (setf (aref new-next-vector i) next)
359 (setf (aref new-index-vector index) i)))
363 (set-header-data new-kv-vector
364 sb!vm:vector-valid-hashing-subtype)
365 (let* ((hashing (pointer-hash key))
366 (index (rem hashing new-length))
367 (next (aref new-index-vector index)))
368 (declare (type index index)
370 ;; Push this slot onto the next chain.
371 (setf (aref new-next-vector i) next)
372 (setf (aref new-index-vector index) i))))))
373 (setf (hash-table-table table) new-kv-vector)
374 (setf (hash-table-index-vector table) new-index-vector)
375 (setf (hash-table-next-vector table) new-next-vector)
376 (setf (hash-table-hash-vector table) new-hash-vector)
377 ;; Shrink the old vectors to 0 size to help the conservative GC.
378 (%shrink-vector old-kv-vector 0)
379 (%shrink-vector old-index-vector 0)
380 (%shrink-vector old-next-vector 0)
381 (when old-hash-vector
382 (%shrink-vector old-hash-vector 0))
383 (setf (hash-table-rehash-trigger table) new-size))
386 ;;; Use the same size as before, re-using the vectors.
387 (defun rehash-without-growing (table)
388 (declare (type hash-table table))
389 (let* ((kv-vector (hash-table-table table))
390 (next-vector (hash-table-next-vector table))
391 (hash-vector (hash-table-hash-vector table))
392 (size (length next-vector))
393 (index-vector (hash-table-index-vector table))
394 (length (length index-vector)))
395 (declare (type index size length))
397 ;; Non-empty weak hash tables always need GC support.
398 (unless (and (hash-table-weakness table) (plusp (hash-table-count table)))
399 ;; Disable GC tricks, they will be re-enabled during the re-hash
401 (set-header-data kv-vector sb!vm:vector-normal-subtype))
403 ;; Rehash all the entries.
404 (setf (hash-table-next-free-kv table) 0)
405 (setf (hash-table-needing-rehash table) 0)
407 (setf (aref next-vector i) 0))
409 (setf (aref index-vector i) 0))
410 (do ((i (1- size) (1- i)))
412 (declare (type index/2 i))
413 (let ((key (aref kv-vector (* 2 i)))
414 (value (aref kv-vector (1+ (* 2 i)))))
415 (cond ((and (eq key +empty-ht-slot+)
416 (eq value +empty-ht-slot+))
417 ;; Slot is empty, push it onto free list.
418 (setf (aref next-vector i) (hash-table-next-free-kv table))
419 (setf (hash-table-next-free-kv table) i))
420 ((and hash-vector (not (= (aref hash-vector i)
421 +magic-hash-vector-value+)))
422 ;; Can use the existing hash value (not EQ based)
423 (let* ((hashing (aref hash-vector i))
424 (index (rem hashing length))
425 (next (aref index-vector index)))
426 (declare (type index index))
427 ;; Push this slot into the next chain.
428 (setf (aref next-vector i) next)
429 (setf (aref index-vector index) i)))
433 (set-header-data kv-vector sb!vm:vector-valid-hashing-subtype)
434 (let* ((hashing (pointer-hash key))
435 (index (rem hashing length))
436 (next (aref index-vector index)))
437 (declare (type index index)
439 ;; Push this slot into the next chain.
440 (setf (aref next-vector i) next)
441 (setf (aref index-vector index) i)))))))
444 (defun flush-needing-rehash (table)
445 (let* ((kv-vector (hash-table-table table))
446 (index-vector (hash-table-index-vector table))
447 (next-vector (hash-table-next-vector table))
448 (length (length index-vector)))
449 (do ((next (hash-table-needing-rehash table)))
451 (declare (type index/2 next))
452 (let* ((key (aref kv-vector (* 2 next)))
453 (hashing (pointer-hash key))
454 (index (rem hashing length))
455 (temp (aref next-vector next)))
456 (setf (aref next-vector next) (aref index-vector index))
457 (setf (aref index-vector index) next)
459 (setf (hash-table-needing-rehash table) 0)
462 (defun gethash (key hash-table &optional default)
464 "Finds the entry in HASH-TABLE whose key is KEY and returns the associated
465 value and T as multiple values, or returns DEFAULT and NIL if there is no
466 such entry. Entries can be added using SETF."
467 (declare (type hash-table hash-table)
468 (values t (member t nil)))
469 (gethash3 key hash-table default))
471 (defun gethash2 (key hash-table)
473 "Two argument version of GETHASH"
474 (declare (type hash-table hash-table)
475 (values t (member t nil)))
476 (gethash3 key hash-table nil))
478 (defun gethash3 (key hash-table default)
480 "Three argument version of GETHASH"
481 (declare (type hash-table hash-table)
482 (values t (member t nil)))
483 (with-spinlock-and-without-gcing ((hash-table-spinlock hash-table))
484 (cond ((= (get-header-data (hash-table-table hash-table))
485 sb!vm:vector-must-rehash-subtype)
486 (rehash-without-growing hash-table))
487 ((not (zerop (hash-table-needing-rehash hash-table)))
488 (flush-needing-rehash hash-table)))
490 ;; First check the cache. Use EQ here for speed.
491 (let ((cache (hash-table-cache hash-table))
492 (table (hash-table-table hash-table)))
494 (if (and cache (< cache (length table)) (eq (aref table cache) key))
495 (values (aref table (1+ cache)) t)
497 ;; Search for key in the hash table.
498 (multiple-value-bind (hashing eq-based)
499 (funcall (hash-table-hash-fun hash-table) key)
500 (declare (type hash hashing))
501 (let* ((index-vector (hash-table-index-vector hash-table))
502 (length (length index-vector))
503 (index (rem hashing length))
504 (next (aref index-vector index))
505 (next-vector (hash-table-next-vector hash-table))
506 (hash-vector (hash-table-hash-vector hash-table))
507 (test-fun (hash-table-test-fun hash-table)))
508 (declare (type index index))
509 ;; Search next-vector chain for a matching key.
510 (if (or eq-based (not hash-vector))
511 (do ((next next (aref next-vector next)))
512 ((zerop next) (values default nil))
513 (declare (type index/2 next))
514 (when (eq key (aref table (* 2 next)))
515 (setf (hash-table-cache hash-table) (* 2 next))
516 (return (values (aref table (1+ (* 2 next))) t))))
517 (do ((next next (aref next-vector next)))
518 ((zerop next) (values default nil))
519 (declare (type index/2 next))
520 (when (and (= hashing (aref hash-vector next))
521 (funcall test-fun key (aref table (* 2 next))))
523 (setf (hash-table-cache hash-table) (* 2 next))
524 (return (values (aref table (1+ (* 2 next))) t)))))))))))
526 ;;; so people can call #'(SETF GETHASH)
527 (defun (setf gethash) (new-value key table &optional default)
528 (declare (ignore default))
529 (%puthash key table new-value))
531 (defun %puthash (key hash-table value)
532 (declare (type hash-table hash-table))
533 (aver (hash-table-index-vector hash-table))
534 (with-spinlock-and-without-gcing ((hash-table-spinlock hash-table))
535 ;; We need to rehash here so that a current key can be found if it
536 ;; exists. Check that there is room for one more entry. May not be
537 ;; needed if the key is already present.
538 (cond ((zerop (hash-table-next-free-kv hash-table))
540 ((= (get-header-data (hash-table-table hash-table))
541 sb!vm:vector-must-rehash-subtype)
542 (rehash-without-growing hash-table))
543 ((not (zerop (hash-table-needing-rehash hash-table)))
544 (flush-needing-rehash hash-table)))
546 (let ((cache (hash-table-cache hash-table))
547 (kv-vector (hash-table-table hash-table)))
550 (if (and cache (< cache (length kv-vector))
551 (eq (aref kv-vector cache) key))
552 ;; If cached, just store here
553 (setf (aref kv-vector (1+ cache)) value)
555 ;; Search for key in the hash table.
556 (multiple-value-bind (hashing eq-based)
557 (funcall (hash-table-hash-fun hash-table) key)
558 (declare (type hash hashing))
559 (let* ((index-vector (hash-table-index-vector hash-table))
560 (length (length index-vector))
561 (index (rem hashing length))
562 (next (aref index-vector index))
563 (kv-vector (hash-table-table hash-table))
564 (next-vector (hash-table-next-vector hash-table))
565 (hash-vector (hash-table-hash-vector hash-table))
566 (test-fun (hash-table-test-fun hash-table)))
567 (declare (type index index next))
568 (when (hash-table-weakness hash-table)
569 (set-header-data kv-vector sb!vm:vector-valid-hashing-subtype))
570 (cond ((or eq-based (not hash-vector))
572 (set-header-data kv-vector
573 sb!vm:vector-valid-hashing-subtype))
575 ;; Search next-vector chain for a matching key.
576 (do ((next next (aref next-vector next)))
578 (declare (type index/2 next))
579 (when (eq key (aref kv-vector (* 2 next)))
580 ;; Found, just replace the value.
581 (setf (hash-table-cache hash-table) (* 2 next))
582 (setf (aref kv-vector (1+ (* 2 next))) value)
583 (return-from %puthash value))))
585 ;; Search next-vector chain for a matching key.
586 (do ((next next (aref next-vector next)))
588 (declare (type index/2 next))
589 (when (and (= hashing (aref hash-vector next))
590 (funcall test-fun key
591 (aref kv-vector (* 2 next))))
592 ;; Found, just replace the value.
593 (setf (hash-table-cache hash-table) (* 2 next))
594 (setf (aref kv-vector (1+ (* 2 next))) value)
595 (return-from %puthash value)))))
597 ;; Pop a KV slot off the free list
598 (let ((free-kv-slot (hash-table-next-free-kv hash-table)))
599 (declare (type index/2 free-kv-slot))
600 ;; Double-check for overflow.
601 (aver (not (zerop free-kv-slot)))
602 (setf (hash-table-next-free-kv hash-table)
603 (aref next-vector free-kv-slot))
604 (incf (hash-table-number-entries hash-table))
606 (setf (hash-table-cache hash-table) (* 2 free-kv-slot))
607 (setf (aref kv-vector (* 2 free-kv-slot)) key)
608 (setf (aref kv-vector (1+ (* 2 free-kv-slot))) value)
610 ;; Setup the hash-vector if necessary.
613 (setf (aref hash-vector free-kv-slot) hashing)
614 (aver (= (aref hash-vector free-kv-slot)
615 +magic-hash-vector-value+))))
617 ;; Push this slot into the next chain.
618 (setf (aref next-vector free-kv-slot) next)
619 (setf (aref index-vector index) free-kv-slot)))))))
622 (defun remhash (key hash-table)
624 "Remove the entry in HASH-TABLE associated with KEY. Return T if there
625 was such an entry, or NIL if not."
626 (declare (type hash-table hash-table)
627 (values (member t nil)))
628 (with-spinlock-and-without-gcing ((hash-table-spinlock hash-table))
629 ;; We need to rehash here so that a current key can be found if it
631 (cond ((= (get-header-data (hash-table-table hash-table))
632 sb!vm:vector-must-rehash-subtype)
633 (rehash-without-growing hash-table))
634 ((not (zerop (hash-table-needing-rehash hash-table)))
635 (flush-needing-rehash hash-table)))
637 ;; For now, just clear the cache
638 (setf (hash-table-cache hash-table) nil)
640 ;; Search for key in the hash table.
641 (multiple-value-bind (hashing eq-based)
642 (funcall (hash-table-hash-fun hash-table) key)
643 (declare (type hash hashing))
644 (let* ((index-vector (hash-table-index-vector hash-table))
645 (length (length index-vector))
646 (index (rem hashing length))
647 (next (aref index-vector index))
648 (table (hash-table-table hash-table))
649 (next-vector (hash-table-next-vector hash-table))
650 (hash-vector (hash-table-hash-vector hash-table))
651 (test-fun (hash-table-test-fun hash-table)))
652 (declare (type index index)
654 (flet ((clear-slot (chain-vector prior-slot-location slot-location)
655 (declare (type index/2 slot-location))
656 ;; Mark slot as empty.
657 (setf (aref table (* 2 slot-location)) +empty-ht-slot+
658 (aref table (1+ (* 2 slot-location))) +empty-ht-slot+)
659 ;; Update the prior pointer in the chain to skip this.
660 (setf (aref chain-vector prior-slot-location)
661 (aref next-vector slot-location))
662 ;; Push KV slot onto free chain.
663 (setf (aref next-vector slot-location)
664 (hash-table-next-free-kv hash-table))
665 (setf (hash-table-next-free-kv hash-table) slot-location)
667 (setf (aref hash-vector slot-location)
668 +magic-hash-vector-value+))
669 (decf (hash-table-number-entries hash-table))
673 ((if (or eq-based (not hash-vector))
674 (eq key (aref table (* 2 next)))
675 (and (= hashing (aref hash-vector next))
676 (funcall test-fun key (aref table (* 2 next)))))
677 (clear-slot index-vector index next))
678 ;; Search next-vector chain for a matching key.
679 ((or eq-based (not hash-vector))
681 (do ((prior next next)
682 (next (aref next-vector next) (aref next-vector next)))
684 (declare (type index next))
685 (when (eq key (aref table (* 2 next)))
686 (return-from remhash (clear-slot next-vector prior next)))))
689 (do ((prior next next)
690 (next (aref next-vector next) (aref next-vector next)))
692 (declare (type index/2 next))
693 (when (and (= hashing (aref hash-vector next))
694 (funcall test-fun key (aref table (* 2 next))))
696 (clear-slot next-vector prior next)))))))))))
698 (defun clrhash (hash-table)
700 "This removes all the entries from HASH-TABLE and returns the hash table
702 (declare (optimize speed))
703 (with-spinlock-and-without-gcing ((hash-table-spinlock hash-table))
704 (let* ((kv-vector (hash-table-table hash-table))
705 (next-vector (hash-table-next-vector hash-table))
706 (hash-vector (hash-table-hash-vector hash-table))
707 (size (length next-vector))
708 (index-vector (hash-table-index-vector hash-table)))
709 ;; Disable GC tricks.
710 (set-header-data kv-vector sb!vm:vector-normal-subtype)
711 ;; Mark all slots as empty by setting all keys and values to magic
713 (aver (eq (aref kv-vector 0) hash-table))
714 (fill kv-vector +empty-ht-slot+ :start 2)
715 ;; Set up the free list, all free.
718 (setf (aref next-vector i) (1+ i)))
719 (setf (aref next-vector (1- size)) 0)
720 (setf (hash-table-next-free-kv hash-table) 1)
721 (setf (hash-table-needing-rehash hash-table) 0)
722 ;; Clear the index-vector.
723 (fill index-vector 0)
724 ;; Clear the hash-vector.
726 (fill hash-vector +magic-hash-vector-value+)))
727 (setf (hash-table-cache hash-table) nil)
728 (setf (hash-table-number-entries hash-table) 0))
733 ;;; FIXME: This should be made into a compiler transform for two reasons:
734 ;;; 1. It would then be available for compiling the entire system,
735 ;;; not only parts of the system which are defined after DEFUN MAPHASH.
736 ;;; 2. It could be conditional on compilation policy, so that
737 ;;; it could be compiled as a full call instead of an inline
738 ;;; expansion when SPACE>SPEED.
739 (declaim (inline maphash))
740 (defun maphash (function-designator hash-table)
742 "For each entry in HASH-TABLE, call the designated two-argument function on
743 the key and value of the entry. Return NIL."
744 ;; This essentially duplicates WITH-HASH-TABLE-ITERATOR, so
745 ;; any changes here should be reflected there as well.
746 (let ((fun (%coerce-callable-to-fun function-designator))
747 (size (length (hash-table-next-vector hash-table))))
748 (declare (type function fun))
751 (declare (type index/2 i))
752 (let* ((kv-vector (hash-table-table hash-table))
753 (key (aref kv-vector (* 2 i)))
754 (value (aref kv-vector (1+ (* 2 i)))))
755 ;; We are running without locking or WITHOUT-GCING. For a weak
756 ;; :VALUE hash table it's possible that the GC hit after KEY
757 ;; was read and now the entry is gone. So check if either the
758 ;; key or the value is empty.
759 (unless (or (eq key +empty-ht-slot+)
760 (eq value +empty-ht-slot+))
761 (funcall fun key value))))))
763 ;;;; methods on HASH-TABLE
765 ;;; Return a list of keyword args and values to use for MAKE-HASH-TABLE
766 ;;; when reconstructing HASH-TABLE.
767 (defun %hash-table-ctor-args (hash-table)
768 `(:test ',(hash-table-test hash-table)
769 :size ',(hash-table-size hash-table)
770 :rehash-size ',(hash-table-rehash-size hash-table)
771 :rehash-threshold ',(hash-table-rehash-threshold hash-table)
772 :weakness ',(hash-table-weakness hash-table)))
774 ;;; Return an association list representing the same data as HASH-TABLE.
775 (defun %hash-table-alist (hash-table)
777 (maphash (lambda (key value)
778 (push (cons key value) result))
782 ;;; Stuff an association list into HASH-TABLE. Return the hash table,
783 ;;; so that we can use this for the *PRINT-READABLY* case in
784 ;;; PRINT-OBJECT (HASH-TABLE T) without having to worry about LET
785 ;;; forms and readable gensyms and stuff.
786 (defun %stuff-hash-table (hash-table alist)
788 (setf (gethash (car x) hash-table) (cdr x)))
791 (def!method print-object ((hash-table hash-table) stream)
792 (declare (type stream stream))
793 (cond ((or (not *print-readably*) (not *read-eval*))
794 (print-unreadable-object (hash-table stream :type t :identity t)
797 (hash-table-test hash-table)
798 (hash-table-count hash-table))))
800 (with-standard-io-syntax
803 `(%stuff-hash-table (make-hash-table ,@(%hash-table-ctor-args
805 ',(%hash-table-alist hash-table)))))))
807 (def!method make-load-form ((hash-table hash-table) &optional environment)
808 (declare (ignore environment))
809 (values `(make-hash-table ,@(%hash-table-ctor-args hash-table))
810 `(%stuff-hash-table ,hash-table ',(%hash-table-alist hash-table))))