(in-package "SB!IMPL")
-;;; Like CMU CL, we use HEAPSORT. However, other than that, this code
-;;; isn't really related to the CMU CL code, since instead of trying
-;;; to generalize the CMU CL code to allow START and END values, this
-;;; code has been written from scratch following Chapter 7 of
-;;; _Introduction to Algorithms_ by Corman, Rivest, and Shamir.
-(macrolet ((%index (x) `(truly-the index ,x))
- (%parent (i) `(ash ,i -1))
- (%left (i) `(%index (ash ,i 1)))
- (%right (i) `(%index (1+ (ash ,i 1))))
- (%heapify (i)
- `(do* ((i ,i)
- (left (%left i) (%left i)))
- ((> left current-heap-size))
- (declare (type index i left))
- (let* ((i-elt (%elt i))
- (i-key (funcall keyfun i-elt))
- (left-elt (%elt left))
- (left-key (funcall keyfun left-elt)))
- (multiple-value-bind (large large-elt large-key)
- (if (funcall predicate i-key left-key)
- (values left left-elt left-key)
- (values i i-elt i-key))
- (let ((right (%right i)))
- (multiple-value-bind (largest largest-elt)
- (if (> right current-heap-size)
- (values large large-elt)
- (let* ((right-elt (%elt right))
- (right-key (funcall keyfun right-elt)))
- (if (funcall predicate large-key right-key)
- (values right right-elt)
- (values large large-elt))))
- (cond ((= largest i)
- (return))
- (t
- (setf (%elt i) largest-elt
- (%elt largest) i-elt
- i largest)))))))))
- (%sort-vector (keyfun &optional (vtype 'vector))
- `(macrolet (;; KLUDGE: In SBCL ca. 0.6.10, I had trouble getting
- ;; type inference to propagate all the way
- ;; through this tangled mess of inlining. The
- ;; TRULY-THE here works around that. -- WHN
- (%elt (i)
- `(aref (truly-the ,',vtype vector)
- (%index (+ (%index ,i) start-1)))))
- (let ((start-1 (1- start)) ; Heaps prefer 1-based addressing.
- (current-heap-size (- end start))
- (keyfun ,keyfun))
- (declare (type (integer -1 #.(1- most-positive-fixnum))
- start-1))
- (declare (type index current-heap-size))
- (declare (type function keyfun))
- (loop for i of-type index
- from (ash current-heap-size -1) downto 1 do
- (%heapify i))
- (loop
- (when (< current-heap-size 2)
- (return))
- (rotatef (%elt 1) (%elt current-heap-size))
- (decf current-heap-size)
- (%heapify 1))))))
-
- (declaim (inline sort-vector))
- (defun sort-vector (vector start end predicate key)
- (declare (type vector vector))
- (declare (type index start end))
- (declare (type function predicate))
- (declare (type (or function null) key))
- ;; This used to be (OPTIMIZE (SPEED 3) (SAFETY 3)), but now
- ;; (0.7.1.39) that (SAFETY 3) means "absolutely safe (including
- ;; expensive things like %DETECT-STACK-EXHAUSTION)" we get closer
- ;; to what we want by using (SPEED 2) (SAFETY 2): "pretty fast,
- ;; pretty safe, and safety is no more important than speed".
- (declare (optimize (speed 2) (safety 2) (debug 1) (space 1)))
- (if (typep vector 'simple-vector)
- ;; (VECTOR T) is worth optimizing for, and SIMPLE-VECTOR is
- ;; what we get from (VECTOR T) inside WITH-ARRAY-DATA.
- (if (null key)
- ;; Special-casing the KEY=NIL case lets us avoid some
- ;; function calls.
- (%sort-vector #'identity simple-vector)
- (%sort-vector key simple-vector))
- ;; It's hard to anticipate many speed-critical applications for
- ;; sorting vector types other than (VECTOR T), so we just lump
- ;; them all together in one slow dynamically typed mess.
- (locally
- (declare (optimize (speed 2) (space 2) (inhibit-warnings 3)))
- (%sort-vector (or key #'identity))))))
+(defun sort-vector (vector start end predicate-fun key-fun-or-nil)
+ (sort-vector vector start end predicate-fun key-fun-or-nil))
;;; This is MAYBE-INLINE because it's not too hard to have an
;;; application where sorting is a major bottleneck, and inlining it
;;; allows the compiler to make enough optimizations that it might be
;;; worth the (large) cost in space.
(declaim (maybe-inline sort))
-(defun sort (sequence predicate &key key)
+(defun sort (sequence predicate &rest args &key key)
#!+sb-doc
"Destructively sort SEQUENCE. PREDICATE should return non-NIL if
ARG1 is to precede ARG2."
- (let ((predicate-function (%coerce-callable-to-fun predicate))
- (key-function (and key (%coerce-callable-to-fun key))))
- (typecase sequence
- (list (sort-list sequence predicate-function key-function))
- (vector
- (with-array-data ((vector (the vector sequence))
- (start 0)
- (end (length sequence)))
- (sort-vector vector start end predicate-function key-function))
- sequence)
- (t
- (error 'simple-type-error
- :datum sequence
- :expected-type 'sequence
- :format-control "~S is not a sequence."
- :format-arguments (list sequence))))))
+ (declare (dynamic-extent args))
+ (let ((predicate-fun (%coerce-callable-to-fun predicate)))
+ (seq-dispatch sequence
+ (stable-sort-list sequence
+ predicate-fun
+ (if key (%coerce-callable-to-fun key) #'identity))
+ (let ((key-fun-or-nil (and key (%coerce-callable-to-fun key))))
+ (with-array-data ((vector (the vector sequence))
+ (start 0)
+ (end (length sequence)))
+ (sort-vector vector start end predicate-fun key-fun-or-nil))
+ sequence)
+ (apply #'sb!sequence:sort sequence predicate args))))
\f
;;;; stable sorting
-
-(defun stable-sort (sequence predicate &key key)
+(defun stable-sort (sequence predicate &rest args &key key)
#!+sb-doc
- "Destructively sorts sequence. Predicate should return non-Nil if
- Arg1 is to precede Arg2."
- (typecase sequence
- (simple-vector
- (stable-sort-simple-vector sequence predicate key))
- (list
- (sort-list sequence predicate key))
- (vector
- (stable-sort-vector sequence predicate key))
- (t
- (error 'simple-type-error
- :datum sequence
- :expected-type 'sequence
- :format-control "~S is not a sequence."
- :format-arguments (list sequence)))))
+ "Destructively sort SEQUENCE. PREDICATE should return non-NIL if
+ ARG1 is to precede ARG2."
+ (declare (dynamic-extent args))
+ (let ((predicate-fun (%coerce-callable-to-fun predicate)))
+ (seq-dispatch sequence
+ (stable-sort-list sequence
+ predicate-fun
+ (if key (%coerce-callable-to-fun key) #'identity))
+ (if (typep sequence 'simple-vector)
+ (stable-sort-simple-vector sequence
+ predicate-fun
+ (and key (%coerce-callable-to-fun key)))
+ (stable-sort-vector sequence
+ predicate-fun
+ (and key (%coerce-callable-to-fun key))))
+ (apply #'sb!sequence:stable-sort sequence predicate args))))
+\f
+;;; FUNCALL-USING-KEY saves us a function call sometimes.
+(eval-when (:compile-toplevel :execute)
+ (sb!xc:defmacro funcall2-using-key (pred key one two)
+ `(if ,key
+ (funcall ,pred (funcall ,key ,one)
+ (funcall ,key ,two))
+ (funcall ,pred ,one ,two)))
+) ; EVAL-WHEN
+\f
+;;;; stable sort of lists
-;;; stable sort of lists
+(defun last-cons-of (list)
+ (loop (let ((rest (rest list)))
+ (if rest
+ (setf list rest)
+ (return list)))))
-;;; SORT-LIST uses a bottom up merge sort. First a pass is made over
-;;; the list grabbing one element at a time and merging it with the
-;;; next one form pairs of sorted elements. Then n is doubled, and
-;;; elements are taken in runs of two, merging one run with the next
-;;; to form quadruples of sorted elements. This continues until n is
-;;; large enough that the inner loop only runs for one iteration; that
-;;; is, there are only two runs that can be merged, the first run
+;;; Destructively merge LIST-1 with LIST-2 (given that they're already
+;;; sorted w.r.t. PRED-FUN on KEY-FUN, giving output sorted the same
+;;; way). In the resulting list, elements of LIST-1 are guaranteed to
+;;; come before equal elements of LIST-2.
+;;;
+;;; Return (VALUES HEAD TAILTAIL), where HEAD is the same value you'd
+;;; expect from MERGE, and TAILTAIL is the last cons in the list (i.e.
+;;; the last cons in the list which NRECONC calls TAIL).
+(defun merge-lists* (list-1 list-2 pred-fun key-fun)
+ (declare (type list list-1 list-2))
+ (declare (type function pred-fun key-fun))
+ (cond ((null list-1) (values list-2 (last-cons-of list-2)))
+ ((null list-2) (values list-1 (last-cons-of list-1)))
+ (t (let* ((reversed-result-so-far nil)
+ (key-1 (funcall key-fun (car list-1)))
+ (key-2 (funcall key-fun (car list-2))))
+ (loop
+ (macrolet ((frob (list-i key-i other-list)
+ `(progn
+ ;; basically
+ ;; (PUSH (POP ,LIST-I) REVERSED-RESULT-SO-FAR),
+ ;; except doing some fancy footwork to
+ ;; reuse the cons cell:
+ (psetf (cdr ,list-i) reversed-result-so-far
+ reversed-result-so-far ,list-i
+ ,list-i (cdr ,list-i))
+ ;; Now maybe we're done.
+ (if (endp ,list-i)
+ (return (values (nreconc
+ reversed-result-so-far
+ ,other-list)
+ (last-cons-of
+ ,other-list)))
+ (setf ,key-i
+ (funcall key-fun (car ,list-i)))))))
+ ;; Note that by making KEY-2 the first arg to
+ ;; PRED-FUN, we arrange that if PRED-FUN is a function
+ ;; in the #'< style, the outcome is stably sorted.
+ (if (funcall pred-fun key-2 key-1)
+ (frob list-2 key-2 list-1)
+ (frob list-1 key-1 list-2))))))))
+
+;;; STABLE-SORT-LIST uses a bottom-up merge sort. First a pass is made
+;;; over the list grabbing one element at a time and merging it with
+;;; the next one to form pairs of sorted elements. Then N is doubled,
+;;; and elements are taken in runs of two, merging one run with the
+;;; next to form quadruples of sorted elements. This continues until N
+;;; is large enough that the inner loop only runs for one iteration;
+;;; that is, there are only two runs that can be merged, the first run
;;; starting at the beginning of the list, and the second being the
;;; remaining elements.
-
-(defun sort-list (list pred key)
+(defun stable-sort-list (list pred-fun key-fun)
(let ((head (cons :header list)) ; head holds on to everything
- (n 1) ; bottom-up size of lists to be merged
- unsorted ; unsorted is the remaining list to be
- ; broken into n size lists and merged
- list-1 ; list-1 is one length n list to be merged
- last) ; last points to the last visited cell
- (declare (fixnum n))
+ (n 1) ; bottom-up size of lists to be merged
+ unsorted ; unsorted is the remaining list to be
+ ; broken into n size lists and merged
+ list-1 ; list-1 is one length n list to be merged
+ last) ; last points to the last visited cell
+ (declare (type function pred-fun key-fun)
+ (type fixnum n))
(loop
- ;; start collecting runs of n at the first element
+ ;; Start collecting runs of N at the first element.
(setf unsorted (cdr head))
- ;; tack on the first merge of two n-runs to the head holder
+ ;; Tack on the first merge of two N-runs to the head holder.
(setf last head)
(let ((n-1 (1- n)))
(declare (fixnum n-1))
(loop
- (setf list-1 unsorted)
- (let ((temp (nthcdr n-1 list-1))
- list-2)
- (cond (temp
- ;; there are enough elements for a second run
- (setf list-2 (cdr temp))
- (setf (cdr temp) nil)
- (setf temp (nthcdr n-1 list-2))
- (cond (temp
- (setf unsorted (cdr temp))
- (setf (cdr temp) nil))
- ;; the second run goes off the end of the list
- (t (setf unsorted nil)))
- (multiple-value-bind (merged-head merged-last)
- (merge-lists* list-1 list-2 pred key)
- (setf (cdr last) merged-head)
- (setf last merged-last))
- (if (null unsorted) (return)))
- ;; if there is only one run, then tack it on to the end
- (t (setf (cdr last) list-1)
- (return)))))
+ (setf list-1 unsorted)
+ (let ((temp (nthcdr n-1 list-1))
+ list-2)
+ (cond (temp
+ ;; There are enough elements for a second run.
+ (setf list-2 (cdr temp))
+ (setf (cdr temp) nil)
+ (setf temp (nthcdr n-1 list-2))
+ (cond (temp
+ (setf unsorted (cdr temp))
+ (setf (cdr temp) nil))
+ ;; The second run goes off the end of the list.
+ (t (setf unsorted nil)))
+ (multiple-value-bind (merged-head merged-last)
+ (merge-lists* list-1 list-2 pred-fun key-fun)
+ (setf (cdr last) merged-head
+ last merged-last))
+ (if (null unsorted) (return)))
+ ;; If there is only one run, then tack it on to the end.
+ (t (setf (cdr last) list-1)
+ (return)))))
(setf n (ash n 1)) ; (+ n n)
;; If the inner loop only executed once, then there were only
;; enough elements for two runs given n, so all the elements
;; have been merged into one list. This may waste one outer
;; iteration to realize.
(if (eq list-1 (cdr head))
- (return list-1))))))
-
-;;; APPLY-PRED saves us a function call sometimes.
-(eval-when (:compile-toplevel :execute)
- (sb!xc:defmacro apply-pred (one two pred key)
- `(if ,key
- (funcall ,pred (funcall ,key ,one)
- (funcall ,key ,two))
- (funcall ,pred ,one ,two)))
-) ; EVAL-WHEN
-
-(defvar *merge-lists-header* (list :header))
-
-;;; MERGE-LISTS* originally written by Jim Large.
-;;; modified to return a pointer to the end of the result
-;;; and to not cons header each time its called.
-;;; It destructively merges list-1 with list-2. In the resulting
-;;; list, elements of list-2 are guaranteed to come after equal elements
-;;; of list-1.
-(defun merge-lists* (list-1 list-2 pred key)
- (do* ((result *merge-lists-header*)
- (P result)) ; points to last cell of result
- ((or (null list-1) (null list-2)) ; done when either list used up
- (if (null list-1) ; in which case, append the
- (rplacd p list-2) ; other list
- (rplacd p list-1))
- (do ((drag p lead)
- (lead (cdr p) (cdr lead)))
- ((null lead)
- (values (prog1 (cdr result) ; Return the result sans header
- (rplacd result nil)) ; (free memory, be careful)
- drag)))) ; and return pointer to last element.
- (cond ((apply-pred (car list-2) (car list-1) pred key)
- (rplacd p list-2) ; Append the lesser list to last cell of
- (setq p (cdr p)) ; result. Note: test must bo done for
- (pop list-2)) ; LIST-2 < LIST-1 so merge will be
- (T (rplacd p list-1) ; stable for LIST-1.
- (setq p (cdr p))
- (pop list-1)))))
-
-;;; stable sort of vectors
+ (return list-1))))))
+\f
+;;;; stable sort of vectors
;;; Stable sorting vectors is done with the same algorithm used for
;;; lists, using a temporary vector to merge back and forth between it
;;; and merges them into a target vector starting at index start-1.
(sb!xc:defmacro stable-sort-merge-vectors* (source target start-1 end-1 end-2
- pred key source-ref
- target-ref)
+ pred key source-ref
+ target-ref)
(let ((i (gensym))
- (j (gensym))
- (target-i (gensym)))
+ (j (gensym))
+ (target-i (gensym)))
`(let ((,i ,start-1)
- (,j ,end-1) ; start-2
- (,target-i ,start-1))
+ (,j ,end-1) ; start-2
+ (,target-i ,start-1))
(declare (fixnum ,i ,j ,target-i))
(loop
- (cond ((= ,i ,end-1)
- (loop (if (= ,j ,end-2) (return))
- (setf (,target-ref ,target ,target-i)
- (,source-ref ,source ,j))
- (incf ,target-i)
- (incf ,j))
- (return))
- ((= ,j ,end-2)
- (loop (if (= ,i ,end-1) (return))
- (setf (,target-ref ,target ,target-i)
- (,source-ref ,source ,i))
- (incf ,target-i)
- (incf ,i))
- (return))
- ((apply-pred (,source-ref ,source ,j)
- (,source-ref ,source ,i)
- ,pred ,key)
- (setf (,target-ref ,target ,target-i)
- (,source-ref ,source ,j))
- (incf ,j))
- (t (setf (,target-ref ,target ,target-i)
- (,source-ref ,source ,i))
- (incf ,i)))
- (incf ,target-i)))))
+ (cond ((= ,i ,end-1)
+ (loop (if (= ,j ,end-2) (return))
+ (setf (,target-ref ,target ,target-i)
+ (,source-ref ,source ,j))
+ (incf ,target-i)
+ (incf ,j))
+ (return))
+ ((= ,j ,end-2)
+ (loop (if (= ,i ,end-1) (return))
+ (setf (,target-ref ,target ,target-i)
+ (,source-ref ,source ,i))
+ (incf ,target-i)
+ (incf ,i))
+ (return))
+ ((funcall2-using-key ,pred ,key
+ (,source-ref ,source ,j)
+ (,source-ref ,source ,i))
+ (setf (,target-ref ,target ,target-i)
+ (,source-ref ,source ,j))
+ (incf ,j))
+ (t (setf (,target-ref ,target ,target-i)
+ (,source-ref ,source ,i))
+ (incf ,i)))
+ (incf ,target-i)))))
;;; VECTOR-MERGE-SORT is the same algorithm used to stable sort lists,
;;; but it uses a temporary vector. DIRECTION determines whether we
;;; are merging into the temporary (T) or back into the given vector
;;; (NIL).
(sb!xc:defmacro vector-merge-sort (vector pred key vector-ref)
- (let ((vector-len (gensym)) (n (gensym))
- (direction (gensym)) (unsorted (gensym))
- (start-1 (gensym)) (end-1 (gensym))
- (end-2 (gensym)) (temp-len (gensym))
- (i (gensym)))
- `(let ((,vector-len (length (the vector ,vector)))
- (,n 1) ; bottom-up size of contiguous runs to be merged
- (,direction t) ; t vector --> temp nil temp --> vector
- (,temp-len (length (the simple-vector *merge-sort-temp-vector*)))
- (,unsorted 0) ; unsorted..vector-len are the elements that need
- ; to be merged for a given n
- (,start-1 0)) ; one n-len subsequence to be merged with the next
- (declare (fixnum ,vector-len ,n ,temp-len ,unsorted ,start-1))
+ (with-unique-names
+ (vector-len n direction unsorted start-1 end-1 end-2 temp temp-len i)
+ `(let* ((,vector-len (length (the vector ,vector)))
+ (,n 1) ; bottom-up size of contiguous runs to be merged
+ (,direction t) ; t vector --> temp nil temp --> vector
+ (,temp *merge-sort-temp-vector*)
+ (,temp-len (length ,temp))
+ (,unsorted 0) ; unsorted..vector-len are the elements that need
+ ; to be merged for a given n
+ (,start-1 0)) ; one n-len subsequence to be merged with the next
+ (declare (fixnum ,vector-len ,n ,temp-len ,unsorted ,start-1)
+ (simple-vector ,temp))
(if (> ,vector-len ,temp-len)
- (setf *merge-sort-temp-vector*
- (make-array (max ,vector-len (+ ,temp-len ,temp-len)))))
- (loop
- ;; for each n, we start taking n-runs from the start of the vector
- (setf ,unsorted 0)
- (loop
- (setf ,start-1 ,unsorted)
- (let ((,end-1 (+ ,start-1 ,n)))
- (declare (fixnum ,end-1))
- (cond ((< ,end-1 ,vector-len)
- ;; there are enough elements for a second run
- (let ((,end-2 (+ ,end-1 ,n)))
- (declare (fixnum ,end-2))
- (if (> ,end-2 ,vector-len) (setf ,end-2 ,vector-len))
- (setf ,unsorted ,end-2)
- (if ,direction
- (stable-sort-merge-vectors*
- ,vector *merge-sort-temp-vector*
- ,start-1 ,end-1 ,end-2 ,pred ,key ,vector-ref svref)
- (stable-sort-merge-vectors*
- *merge-sort-temp-vector* ,vector
- ,start-1 ,end-1 ,end-2 ,pred ,key svref ,vector-ref))
- (if (= ,unsorted ,vector-len) (return))))
- ;; if there is only one run, copy those elements to the end
- (t (if ,direction
- (do ((,i ,start-1 (1+ ,i)))
- ((= ,i ,vector-len))
- (declare (fixnum ,i))
- (setf (svref *merge-sort-temp-vector* ,i)
- (,vector-ref ,vector ,i)))
- (do ((,i ,start-1 (1+ ,i)))
- ((= ,i ,vector-len))
- (declare (fixnum ,i))
- (setf (,vector-ref ,vector ,i)
- (svref *merge-sort-temp-vector* ,i))))
- (return)))))
- ;; If the inner loop only executed once, then there were only enough
- ;; elements for two subsequences given n, so all the elements have
- ;; been merged into one list. Start-1 will have remained 0 upon exit.
- (when (zerop ,start-1)
- (if ,direction
- ;; if we just merged into the temporary, copy it all back
- ;; to the given vector.
- (dotimes (,i ,vector-len)
- (setf (,vector-ref ,vector ,i)
- (svref *merge-sort-temp-vector* ,i))))
- (return ,vector))
- (setf ,n (ash ,n 1)) ; (* 2 n)
- (setf ,direction (not ,direction))))))
+ (setf ,temp (make-array (max ,vector-len
+ (min most-positive-fixnum
+ (+ ,temp-len ,temp-len))))
+ *merge-sort-temp-vector* ,temp))
+ ;; rebind, in case PRED or KEY calls STABLE-SORT
+ (let ((*merge-sort-temp-vector* (vector)))
+ (loop
+ ;; for each n, we start taking n-runs from the start of the vector
+ (setf ,unsorted 0)
+ (loop
+ (setf ,start-1 ,unsorted)
+ (let ((,end-1 (+ ,start-1 ,n)))
+ (declare (fixnum ,end-1))
+ (cond ((< ,end-1 ,vector-len)
+ ;; there are enough elements for a second run
+ (let ((,end-2 (+ ,end-1 ,n)))
+ (declare (fixnum ,end-2))
+ (if (> ,end-2 ,vector-len) (setf ,end-2 ,vector-len))
+ (setf ,unsorted ,end-2)
+ (if ,direction
+ (stable-sort-merge-vectors*
+ ,vector ,temp
+ ,start-1 ,end-1 ,end-2 ,pred ,key ,vector-ref svref)
+ (stable-sort-merge-vectors*
+ ,temp ,vector
+ ,start-1 ,end-1 ,end-2 ,pred ,key svref ,vector-ref))
+ (if (= ,unsorted ,vector-len) (return))))
+ ;; if there is only one run, copy those elements to the end
+ (t (if ,direction
+ (do ((,i ,start-1 (1+ ,i)))
+ ((= ,i ,vector-len))
+ (declare (fixnum ,i))
+ (setf (svref ,temp ,i)
+ (,vector-ref ,vector ,i)))
+ (do ((,i ,start-1 (1+ ,i)))
+ ((= ,i ,vector-len))
+ (declare (fixnum ,i))
+ (setf (,vector-ref ,vector ,i)
+ (svref ,temp ,i))))
+ (return)))))
+ ;; If the inner loop only executed once, then there were only enough
+ ;; elements for two subsequences given n, so all the elements have
+ ;; been merged into one list. Start-1 will have remained 0 upon exit.
+ (when (zerop ,start-1)
+ (if ,direction
+ ;; if we just merged into the temporary, copy it all back
+ ;; to the given vector.
+ (dotimes (,i ,vector-len)
+ (setf (,vector-ref ,vector ,i)
+ (svref ,temp ,i))))
+ (return ,vector))
+ (setf ,n (ash ,n 1)) ; (* 2 n)
+ (setf ,direction (not ,direction)))))))
) ; EVAL-when
-;;; temporary vector for stable sorting vectors
-(defvar *merge-sort-temp-vector*
- (make-array 50))
+;;; temporary vector for stable sorting vectors, allocated for each new thread
+(defvar *merge-sort-temp-vector* (make-array 50))
(declaim (simple-vector *merge-sort-temp-vector*))
(defun stable-sort-simple-vector (vector pred key)
- (declare (simple-vector vector))
+ (declare (type simple-vector vector)
+ (type function pred)
+ (type (or null function) key))
(vector-merge-sort vector pred key svref))
(defun stable-sort-vector (vector pred key)
+ (declare (type function pred)
+ (type (or null function) key))
(vector-merge-sort vector pred key aref))
-
+\f
;;;; merging
(eval-when (:compile-toplevel :execute)
;;; are chosen only if they are strictly less than elements of
;;; VECTOR-1, (PRED ELT-2 ELT-1), as specified in the manual.
(sb!xc:defmacro merge-vectors (vector-1 length-1 vector-2 length-2
- result-vector pred key access)
+ result-vector pred key access)
(let ((result-i (gensym))
- (i (gensym))
- (j (gensym)))
+ (i (gensym))
+ (j (gensym)))
`(let* ((,result-i 0)
- (,i 0)
- (,j 0))
+ (,i 0)
+ (,j 0))
(declare (fixnum ,result-i ,i ,j))
(loop
- (cond ((= ,i ,length-1)
- (loop (if (= ,j ,length-2) (return))
- (setf (,access ,result-vector ,result-i)
- (,access ,vector-2 ,j))
- (incf ,result-i)
- (incf ,j))
- (return ,result-vector))
- ((= ,j ,length-2)
- (loop (if (= ,i ,length-1) (return))
- (setf (,access ,result-vector ,result-i)
- (,access ,vector-1 ,i))
- (incf ,result-i)
- (incf ,i))
- (return ,result-vector))
- ((apply-pred (,access ,vector-2 ,j) (,access ,vector-1 ,i)
- ,pred ,key)
- (setf (,access ,result-vector ,result-i)
- (,access ,vector-2 ,j))
- (incf ,j))
- (t (setf (,access ,result-vector ,result-i)
- (,access ,vector-1 ,i))
- (incf ,i)))
- (incf ,result-i)))))
+ (cond ((= ,i ,length-1)
+ (loop (if (= ,j ,length-2) (return))
+ (setf (,access ,result-vector ,result-i)
+ (,access ,vector-2 ,j))
+ (incf ,result-i)
+ (incf ,j))
+ (return ,result-vector))
+ ((= ,j ,length-2)
+ (loop (if (= ,i ,length-1) (return))
+ (setf (,access ,result-vector ,result-i)
+ (,access ,vector-1 ,i))
+ (incf ,result-i)
+ (incf ,i))
+ (return ,result-vector))
+ ((funcall2-using-key ,pred ,key
+ (,access ,vector-2 ,j) (,access ,vector-1 ,i))
+ (setf (,access ,result-vector ,result-i)
+ (,access ,vector-2 ,j))
+ (incf ,j))
+ (t (setf (,access ,result-vector ,result-i)
+ (,access ,vector-1 ,i))
+ (incf ,i)))
+ (incf ,result-i)))))
) ; EVAL-WHEN
#!+sb-doc
"Merge the sequences SEQUENCE1 and SEQUENCE2 destructively into a
sequence of type RESULT-TYPE using PREDICATE to order the elements."
- (if (eq result-type 'list)
- (let ((result (merge-lists* (coerce sequence1 'list)
- (coerce sequence2 'list)
- predicate key)))
- result)
- (let* ((vector-1 (coerce sequence1 'vector))
- (vector-2 (coerce sequence2 'vector))
- (length-1 (length vector-1))
- (length-2 (length vector-2))
- (result (make-sequence-of-type result-type
- (+ length-1 length-2))))
- (declare (vector vector-1 vector-2)
- (fixnum length-1 length-2))
-
- #!+high-security (aver (typep result result-type))
- (if (and (simple-vector-p result)
- (simple-vector-p vector-1)
- (simple-vector-p vector-2))
- (merge-vectors vector-1 length-1 vector-2 length-2
- result predicate key svref)
- (merge-vectors vector-1 length-1 vector-2 length-2
- result predicate key aref)))))
+ ;; FIXME: This implementation is remarkably inefficient in various
+ ;; ways. In decreasing order of estimated user astonishment, I note:
+ ;; full calls to SPECIFIER-TYPE at runtime; copying input vectors
+ ;; to lists before doing MERGE-LISTS*; and walking input lists
+ ;; (because of the call to MERGE-LISTS*, which walks the list to
+ ;; find the last element for its second return value) even in cases
+ ;; like (MERGE 'LIST (LIST 1) (LIST 2 3 4 5 ... 1000)) where one list
+ ;; can be largely ignored. -- WHN 2003-01-05
+ (let ((type (specifier-type result-type)))
+ (cond
+ ((csubtypep type (specifier-type 'list))
+ ;; the VECTOR clause, below, goes through MAKE-SEQUENCE, so
+ ;; benefits from the error checking there. Short of
+ ;; reimplementing everything, we can't do the same for the LIST
+ ;; case, so do relevant length checking here:
+ (let ((s1 (coerce sequence1 'list))
+ (s2 (coerce sequence2 'list))
+ (pred-fun (%coerce-callable-to-fun predicate))
+ (key-fun (if key
+ (%coerce-callable-to-fun key)
+ #'identity)))
+ (when (type= type (specifier-type 'list))
+ (return-from merge (values (merge-lists* s1 s2 pred-fun key-fun))))
+ (when (eq type *empty-type*)
+ (bad-sequence-type-error nil))
+ (when (type= type (specifier-type 'null))
+ (if (and (null s1) (null s2))
+ (return-from merge 'nil)
+ ;; FIXME: This will break on circular lists (as,
+ ;; indeed, will the whole MERGE function).
+ (sequence-type-length-mismatch-error type
+ (+ (length s1)
+ (length s2)))))
+ (if (cons-type-p type)
+ (multiple-value-bind (min exactp)
+ (sb!kernel::cons-type-length-info type)
+ (let ((length (+ (length s1) (length s2))))
+ (if exactp
+ (unless (= length min)
+ (sequence-type-length-mismatch-error type length))
+ (unless (>= length min)
+ (sequence-type-length-mismatch-error type length)))
+ (values (merge-lists* s1 s2 pred-fun key-fun))))
+ (sequence-type-too-hairy result-type))))
+ ((csubtypep type (specifier-type 'vector))
+ (let* ((vector-1 (coerce sequence1 'vector))
+ (vector-2 (coerce sequence2 'vector))
+ (length-1 (length vector-1))
+ (length-2 (length vector-2))
+ (result (make-sequence result-type (+ length-1 length-2))))
+ (declare (vector vector-1 vector-2)
+ (fixnum length-1 length-2))
+ (if (and (simple-vector-p result)
+ (simple-vector-p vector-1)
+ (simple-vector-p vector-2))
+ (merge-vectors vector-1 length-1 vector-2 length-2
+ result predicate key svref)
+ (merge-vectors vector-1 length-1 vector-2 length-2
+ result predicate key aref))))
+ ((and (csubtypep type (specifier-type 'sequence))
+ (find-class result-type nil))
+ (let* ((vector-1 (coerce sequence1 'vector))
+ (vector-2 (coerce sequence2 'vector))
+ (length-1 (length vector-1))
+ (length-2 (length vector-2))
+ (temp (make-array (+ length-1 length-2)))
+ (result (make-sequence result-type (+ length-1 length-2))))
+ (declare (vector vector-1 vector-2) (fixnum length-1 length-2))
+ (merge-vectors vector-1 length-1 vector-2 length-2
+ temp predicate key aref)
+ (replace result temp)
+ result))
+ (t (bad-sequence-type-error result-type)))))
projects / sbcl.git / blobdiff