X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Farray.lisp;h=565c0861a1027283ef001c85ce7ee429ddc20fbc;hb=f066ad2b0b89c016ab9ceaac6de0758e4eb4c1fb;hp=6296eb4901bb2cfb96c079252df0e88bd941ceb2;hpb=a682f4c392bc874a6a898632889319ebdd8821fc;p=sbcl.git diff --git a/src/code/array.lisp b/src/code/array.lisp index 6296eb4..565c086 100644 --- a/src/code/array.lisp +++ b/src/code/array.lisp @@ -12,7 +12,7 @@ (in-package "SB!IMPL") #!-sb-fluid -(declaim (inline fill-pointer array-has-fill-pointer-p adjustable-array-p +(declaim (inline adjustable-array-p array-displacement)) ;;;; miscellaneous accessor functions @@ -30,7 +30,8 @@ (def %array-available-elements) (def %array-data-vector) (def %array-displacement) - (def %array-displaced-p)) + (def %array-displaced-p) + (def %array-diplaced-from)) (defun %array-rank (array) (%array-rank array)) @@ -46,8 +47,11 @@ (fixnum index)) (%check-bound array bound index)) +(defun %with-array-data/fp (array start end) + (%with-array-data-macro array start end :check-bounds t :check-fill-pointer t)) + (defun %with-array-data (array start end) - (%with-array-data-macro array start end :fail-inline? t)) + (%with-array-data-macro array start end :check-bounds t :check-fill-pointer nil)) (defun %data-vector-and-index (array index) (if (array-header-p array) @@ -55,14 +59,6 @@ (%with-array-data array index nil) (values vector index)) (values array index))) - -;;; It'd waste space to expand copies of error handling in every -;;; inline %WITH-ARRAY-DATA, so we have them call this function -;;; instead. This is just a wrapper which is known never to return. -(defun failed-%with-array-data (array start end) - (declare (notinline %with-array-data)) - (%with-array-data array start end) - (bug "called FAILED-%WITH-ARRAY-DATA with valid array parameters?")) ;;;; MAKE-ARRAY (eval-when (:compile-toplevel :execute) @@ -100,6 +96,8 @@ (values #.sb!vm:simple-bit-vector-widetag 1)) ;; OK, we have to wade into SUBTYPEPing after all. (t + (unless *type-system-initialized* + (bug "SUBTYPEP dispatch for MAKE-ARRAY before the type system is ready")) #.`(pick-vector-type type ,@(map 'list (lambda (saetp) @@ -222,6 +220,7 @@ (setf (%array-fill-pointer-p array) nil))) (setf (%array-available-elements array) total-size) (setf (%array-data-vector array) data) + (setf (%array-displaced-from array) nil) (cond (displaced-to (when (or initial-element-p initial-contents-p) (error "Neither :INITIAL-ELEMENT nor :INITIAL-CONTENTS ~ @@ -231,7 +230,8 @@ (array-total-size displaced-to)) (error "~S doesn't have enough elements." displaced-to)) (setf (%array-displacement array) offset) - (setf (%array-displaced-p array) t))) + (setf (%array-displaced-p array) t) + (%save-displaced-array-backpointer array data))) (t (setf (%array-displaced-p array) nil))) (let ((axis 0)) @@ -316,21 +316,150 @@ of specialized arrays is supported." "Construct a SIMPLE-VECTOR from the given objects." (coerce (the list objects) 'simple-vector)) + ;;;; accessor/setter functions -(defun hairy-data-vector-ref (array index) - (with-array-data ((vector array) (index index) (end)) - (declare (ignore end)) - (etypecase vector . - #.(map 'list - (lambda (saetp) - (let* ((type (sb!vm:saetp-specifier saetp)) - (atype `(simple-array ,type (*)))) - `(,atype - (data-vector-ref (the ,atype vector) index)))) - (sort - (copy-seq - sb!vm:*specialized-array-element-type-properties*) - #'> :key #'sb!vm:saetp-importance))))) + +;;; Dispatch to an optimized routine the data vector accessors for +;;; each different specialized vector type. Do dispatching by looking +;;; up the widetag in the array rather than with the typecases, which +;;; as of 1.0.5 compiles to a naive sequence of linear TYPEPs. Also +;;; provide separate versions where bounds checking has been moved +;;; from the callee to the caller, since it's much cheaper to do once +;;; the type information is available. Finally, for each of these +;;; routines also provide a slow path, taken for arrays that are not +;;; vectors or not simple. +(macrolet ((def (name table-name) + `(progn + (defglobal ,table-name (make-array ,(1+ sb!vm:widetag-mask))) + (defmacro ,name (array-var) + `(the function + (let ((tag 0)) + (when (sb!vm::%other-pointer-p ,array-var) + (setf tag (%other-pointer-widetag ,array-var))) + (svref ,',table-name tag))))))) + (def !find-data-vector-setter %%data-vector-setters%%) + (def !find-data-vector-setter/check-bounds %%data-vector-setters/check-bounds%%) + (def !find-data-vector-reffer %%data-vector-reffers%%) + (def !find-data-vector-reffer/check-bounds %%data-vector-reffers/check-bounds%%)) + +(macrolet ((%ref (accessor-getter extra-params) + `(funcall (,accessor-getter array) array index ,@extra-params)) + (define (accessor-name slow-accessor-name accessor-getter + extra-params check-bounds) + `(progn + (defun ,accessor-name (array index ,@extra-params) + (declare (optimize speed + ;; (SAFETY 0) is ok. All calls to + ;; these functions are generated by + ;; the compiler, so argument count + ;; checking isn't needed. Type checking + ;; is done implicitly via the widetag + ;; dispatch. + (safety 0))) + (%ref ,accessor-getter ,extra-params)) + (defun ,slow-accessor-name (array index ,@extra-params) + (declare (optimize speed (safety 0))) + (if (not (%array-displaced-p array)) + ;; The reasonably quick path of non-displaced complex + ;; arrays. + (let ((array (%array-data-vector array))) + (%ref ,accessor-getter ,extra-params)) + ;; The real slow path. + (with-array-data + ((vector array) + (index (locally + (declare (optimize (speed 1) (safety 1))) + (,@check-bounds index))) + (end) + :force-inline t) + (declare (ignore end)) + (,accessor-name vector index ,@extra-params))))))) + (define hairy-data-vector-ref slow-hairy-data-vector-ref + !find-data-vector-reffer + nil (progn)) + (define hairy-data-vector-set slow-hairy-data-vector-set + !find-data-vector-setter + (new-value) (progn)) + (define hairy-data-vector-ref/check-bounds + slow-hairy-data-vector-ref/check-bounds + !find-data-vector-reffer/check-bounds + nil (%check-bound array (array-dimension array 0))) + (define hairy-data-vector-set/check-bounds + slow-hairy-data-vector-set/check-bounds + !find-data-vector-setter/check-bounds + (new-value) (%check-bound array (array-dimension array 0)))) + +(defun hairy-ref-error (array index &optional new-value) + (declare (ignore index new-value)) + (error 'type-error + :datum array + :expected-type 'vector)) + +;;; Populate the dispatch tables. +(macrolet ((define-reffer (saetp check-form) + (let* ((type (sb!vm:saetp-specifier saetp)) + (atype `(simple-array ,type (*)))) + `(named-lambda optimized-data-vector-ref (vector index) + (declare (optimize speed (safety 0))) + (data-vector-ref (the ,atype vector) + (locally + (declare (optimize (safety 1))) + (the index + (,@check-form index))))))) + (define-setter (saetp check-form) + (let* ((type (sb!vm:saetp-specifier saetp)) + (atype `(simple-array ,type (*)))) + `(named-lambda optimized-data-vector-set (vector index new-value) + (declare (optimize speed (safety 0))) + (data-vector-set (the ,atype vector) + (locally + (declare (optimize (safety 1))) + (the index + (,@check-form index))) + (locally + ;; SPEED 1 needed to avoid the compiler + ;; from downgrading the type check to + ;; a cheaper one. + (declare (optimize (speed 1) + (safety 1))) + (the ,type new-value))) + ;; For specialized arrays, the return from + ;; data-vector-set would have to be reboxed to be a + ;; (Lisp) return value; instead, we use the + ;; already-boxed value as the return. + new-value))) + (define-reffers (symbol deffer check-form slow-path) + `(progn + ;; FIXME/KLUDGE: can't just FILL here, because genesis doesn't + ;; preserve the binding, so re-initiaize as NS doesn't have + ;; the energy to figure out to change that right now. + (setf ,symbol (make-array (1+ sb!vm::widetag-mask) + :initial-element #'hairy-ref-error)) + ,@(loop for widetag in '(sb!vm:complex-vector-widetag + sb!vm:complex-vector-nil-widetag + sb!vm:complex-bit-vector-widetag + #!+sb-unicode sb!vm:complex-character-string-widetag + sb!vm:complex-base-string-widetag + sb!vm:simple-array-widetag + sb!vm:complex-array-widetag) + collect `(setf (svref ,symbol ,widetag) ,slow-path)) + ,@(loop for saetp across sb!vm:*specialized-array-element-type-properties* + for widetag = (sb!vm:saetp-typecode saetp) + collect `(setf (svref ,symbol ,widetag) + (,deffer ,saetp ,check-form)))))) + (defun !hairy-data-vector-reffer-init () + (define-reffers %%data-vector-reffers%% define-reffer + (progn) + #'slow-hairy-data-vector-ref) + (define-reffers %%data-vector-setters%% define-setter + (progn) + #'slow-hairy-data-vector-set) + (define-reffers %%data-vector-reffers/check-bounds%% define-reffer + (%check-bound vector (length vector)) + #'slow-hairy-data-vector-ref/check-bounds) + (define-reffers %%data-vector-setters/check-bounds%% define-setter + (%check-bound vector (length vector)) + #'slow-hairy-data-vector-set/check-bounds))) ;;; (Ordinary DATA-VECTOR-REF usage compiles into a vop, but ;;; DATA-VECTOR-REF is also FOLDABLE, and this ordinary function @@ -338,27 +467,36 @@ of specialized arrays is supported." (defun data-vector-ref (array index) (hairy-data-vector-ref array index)) -(defun hairy-data-vector-set (array index new-value) - (with-array-data ((vector array) (index index) (end)) - (declare (ignore end)) - (etypecase vector . - #.(map 'list - (lambda (saetp) - (let* ((type (sb!vm:saetp-specifier saetp)) - (atype `(simple-array ,type (*)))) - `(,atype - (data-vector-set (the ,atype vector) index - (the ,type new-value)) - ;; For specialized arrays, the return from - ;; data-vector-set would have to be - ;; reboxed to be a (Lisp) return value; - ;; instead, we use the already-boxed value - ;; as the return. - new-value))) - (sort - (copy-seq - sb!vm:*specialized-array-element-type-properties*) - #'> :key #'sb!vm:saetp-importance))))) +(defun data-vector-ref-with-offset (array index offset) + (hairy-data-vector-ref array (+ index offset))) + +(defun invalid-array-p (array) + (and (array-header-p array) + (consp (%array-displaced-p array)))) + +(declaim (ftype (function (array) nil) invalid-array-error)) +(defun invalid-array-error (array) + (aver (array-header-p array)) + ;; Array invalidation stashes the original dimensions here... + (let ((dims (%array-displaced-p array)) + (et (array-element-type array))) + (error 'invalid-array-error + :datum array + :expected-type + (if (cdr dims) + `(array ,et ,dims) + `(vector ,et ,@dims))))) + +(declaim (ftype (function (array integer integer &optional t) nil) + invalid-array-index-error)) +(defun invalid-array-index-error (array index bound &optional axis) + (if (invalid-array-p array) + (invalid-array-error array) + (error 'invalid-array-index-error + :array array + :axis axis + :datum index + :expected-type `(integer 0 (,bound))))) ;;; SUBSCRIPTS has a dynamic-extent list structure and is destroyed (defun %array-row-major-index (array subscripts @@ -381,11 +519,7 @@ of specialized arrays is supported." (declare (fixnum dim)) (unless (and (fixnump index) (< -1 index dim)) (if invalid-index-error-p - (error 'simple-type-error - :format-control "invalid index ~W~[~;~:; on axis ~:*~W~] in ~S" - :format-arguments (list index axis array) - :datum index - :expected-type `(integer 0 (,dim))) + (invalid-array-index-error array index dim axis) (return-from %array-row-major-index nil))) (incf result (* chunk-size (the fixnum index))) (setf chunk-size (* chunk-size dim)))) @@ -393,35 +527,28 @@ of specialized arrays is supported." (length (length (the (simple-array * (*)) array)))) (unless (and (fixnump index) (< -1 index length)) (if invalid-index-error-p - ;; FIXME: perhaps this should share a format-string - ;; with INVALID-ARRAY-INDEX-ERROR or - ;; INDEX-TOO-LARGE-ERROR? - (error 'simple-type-error - :format-control "invalid index ~W in ~S" - :format-arguments (list index array) - :datum index - :expected-type `(integer 0 (,length))) + (invalid-array-index-error array index length) (return-from %array-row-major-index nil))) index)))) (defun array-in-bounds-p (array &rest subscripts) #!+sb-doc - "Return T if the SUBSCIPTS are in bounds for the ARRAY, NIL otherwise." + "Return T if the SUBSCRIPTS are in bounds for the ARRAY, NIL otherwise." (if (%array-row-major-index array subscripts nil) t)) (defun array-row-major-index (array &rest subscripts) - (declare (dynamic-extent subscripts)) + (declare (truly-dynamic-extent subscripts)) (%array-row-major-index array subscripts)) (defun aref (array &rest subscripts) #!+sb-doc "Return the element of the ARRAY specified by the SUBSCRIPTS." - (declare (dynamic-extent subscripts)) + (declare (truly-dynamic-extent subscripts)) (row-major-aref array (%array-row-major-index array subscripts))) (defun %aset (array &rest stuff) - (declare (dynamic-extent stuff)) + (declare (truly-dynamic-extent stuff)) (let ((subscripts (butlast stuff)) (new-value (car (last stuff)))) (setf (row-major-aref array (%array-row-major-index array subscripts)) @@ -454,7 +581,7 @@ of specialized arrays is supported." #!-sb-fluid (declaim (inline (setf aref))) (defun (setf aref) (new-value array &rest subscripts) - (declare (dynamic-extent subscripts)) + (declare (truly-dynamic-extent subscripts)) (declare (type array array)) (setf (row-major-aref array (%array-row-major-index array subscripts)) new-value)) @@ -585,25 +712,7 @@ of specialized arrays is supported." (error "Axis number ~W is too big; ~S only has ~D dimension~:P." axis-number array (%array-rank array))) (t - ;; ANSI sayeth (ADJUST-ARRAY dictionary entry): - ;; - ;; "If A is displaced to B, the consequences are - ;; unspecified if B is adjusted in such a way that it no - ;; longer has enough elements to satisfy A. - ;; - ;; In situations where this matters we should be doing a - ;; bounds-check, which in turn uses ARRAY-DIMENSION -- so - ;; this seems like a good place to signal an error. - (multiple-value-bind (target offset) (array-displacement array) - (when (and target - (> (array-total-size array) - (- (array-total-size target) offset))) - (error 'displaced-to-array-too-small-error - :format-control "~@" - :format-arguments (list (array-total-size array) - (- (array-total-size target) offset)))) - (%array-dimension array axis-number))))) + (%array-dimension array axis-number)))) (defun array-dimensions (array) #!+sb-doc @@ -646,37 +755,45 @@ of specialized arrays is supported." ;;;; fill pointer frobbing stuff +(declaim (inline array-has-fill-pointer-p)) (defun array-has-fill-pointer-p (array) #!+sb-doc "Return T if the given ARRAY has a fill pointer, or NIL otherwise." (declare (array array)) (and (array-header-p array) (%array-fill-pointer-p array))) +(defun fill-pointer-error (vector arg) + (cond (arg + (aver (array-has-fill-pointer-p vector)) + (let ((max (%array-available-elements vector))) + (error 'simple-type-error + :datum arg + :expected-type (list 'integer 0 max) + :format-control "The new fill pointer, ~S, is larger than the length of the vector (~S.)" + :format-arguments (list arg max)))) + (t + (error 'simple-type-error + :datum vector + :expected-type '(and vector (satisfies array-has-fill-pointer-p)) + :format-control "~S is not an array with a fill pointer." + :format-arguments (list vector))))) + +(declaim (inline fill-pointer)) (defun fill-pointer (vector) #!+sb-doc "Return the FILL-POINTER of the given VECTOR." - (declare (vector vector)) - (if (and (array-header-p vector) (%array-fill-pointer-p vector)) + (if (array-has-fill-pointer-p vector) (%array-fill-pointer vector) - (error 'simple-type-error - :datum vector - :expected-type '(and vector (satisfies array-has-fill-pointer-p)) - :format-control "~S is not an array with a fill pointer." - :format-arguments (list vector)))) + (fill-pointer-error vector nil))) (defun %set-fill-pointer (vector new) - (declare (vector vector) (fixnum new)) - (if (and (array-header-p vector) (%array-fill-pointer-p vector)) - (if (> new (%array-available-elements vector)) - (error - "The new fill pointer, ~S, is larger than the length of the vector." - new) - (setf (%array-fill-pointer vector) new)) - (error 'simple-type-error - :datum vector - :expected-type '(and vector (satisfies array-has-fill-pointer-p)) - :format-control "~S is not an array with a fill pointer." - :format-arguments (list vector)))) + (flet ((oops (x) + (fill-pointer-error vector x))) + (if (array-has-fill-pointer-p vector) + (if (> new (%array-available-elements vector)) + (oops new) + (setf (%array-fill-pointer vector) new)) + (oops nil)))) ;;; FIXME: It'd probably make sense to use a MACROLET to share the ;;; guts of VECTOR-PUSH between VECTOR-PUSH-EXTEND. Such a macro @@ -689,25 +806,28 @@ of specialized arrays is supported." to NEW-EL, and increment the fill pointer by one. If the fill pointer is too large, NIL is returned, otherwise the index of the pushed element is returned." - (declare (vector array)) (let ((fill-pointer (fill-pointer array))) (declare (fixnum fill-pointer)) (cond ((= fill-pointer (%array-available-elements array)) nil) (t - (setf (aref array fill-pointer) new-el) + (locally (declare (optimize (safety 0))) + (setf (aref array fill-pointer) new-el)) (setf (%array-fill-pointer array) (1+ fill-pointer)) fill-pointer)))) (defun vector-push-extend (new-element vector &optional - (extension (1+ (length vector)))) - (declare (vector vector) (fixnum extension)) + (min-extension + (let ((length (length vector))) + (min (1+ length) + (- array-dimension-limit length))))) + (declare (fixnum min-extension)) (let ((fill-pointer (fill-pointer vector))) (declare (fixnum fill-pointer)) (when (= fill-pointer (%array-available-elements vector)) - (adjust-array vector (+ fill-pointer extension))) + (adjust-array vector (+ fill-pointer (max 1 min-extension)))) ;; disable bounds checking (locally (declare (optimize (safety 0))) (setf (aref vector fill-pointer) new-element)) @@ -718,7 +838,6 @@ of specialized arrays is supported." #!+sb-doc "Decrease the fill pointer by 1 and return the element pointed to by the new fill pointer." - (declare (vector array)) (let ((fill-pointer (fill-pointer array))) (declare (fixnum fill-pointer)) (if (zerop fill-pointer) @@ -740,6 +859,8 @@ of specialized arrays is supported." displaced-to displaced-index-offset) #!+sb-doc "Adjust ARRAY's dimensions to the given DIMENSIONS and stuff." + (when (invalid-array-p array) + (invalid-array-error array)) (let ((dimensions (if (listp dimensions) dimensions (list dimensions)))) (cond ((/= (the fixnum (length (the list dimensions))) (the fixnum (array-rank array))) @@ -770,7 +891,7 @@ of specialized arrays is supported." (set-array-header array array-data array-size (get-new-fill-pointer array array-size fill-pointer) - 0 dimensions nil) + 0 dimensions nil nil) (if (array-header-p array) ;; simple multidimensional or single dimensional array (make-array dimensions @@ -797,7 +918,7 @@ of specialized arrays is supported." (set-array-header array displaced-to array-size (get-new-fill-pointer array array-size fill-pointer) - displacement dimensions t) + displacement dimensions t nil) ;; simple multidimensional or single dimensional array (make-array dimensions :element-type element-type @@ -827,7 +948,7 @@ of specialized arrays is supported." (set-array-header array new-data new-length (get-new-fill-pointer array new-length fill-pointer) - 0 dimensions nil) + 0 dimensions nil nil) new-data)))) (t (let ((old-length (%array-available-elements array)) @@ -853,12 +974,12 @@ of specialized arrays is supported." initial-element-p)) (if (adjustable-array-p array) (set-array-header array new-data new-length - new-length 0 dimensions nil) + nil 0 dimensions nil nil) (let ((new-array (make-array-header sb!vm:simple-array-widetag array-rank))) (set-array-header new-array new-data new-length - new-length 0 dimensions nil))))))))))) + nil 0 dimensions nil t))))))))))) (defun get-new-fill-pointer (old-array new-array-size fill-pointer) @@ -938,9 +1059,76 @@ of specialized arrays is supported." vector) (t (subseq vector 0 new-length)))) +;;; BIG THREAD SAFETY NOTE +;;; +;;; ADJUST-ARRAY/SET-ARRAY-HEADER, and its callees are very +;;; thread unsafe. They are nonatomic, and can mess with parallel +;;; code using the same arrays. +;;; +;;; A likely seeming fix is an additional level of indirection: +;;; ARRAY-HEADER -> ARRAY-INFO -> ... where ARRAY-HEADER would +;;; hold nothing but the pointer to ARRAY-INFO, and ARRAY-INFO +;;; would hold everything ARRAY-HEADER now holds. This allows +;;; consing up a new ARRAY-INFO and replacing it atomically in +;;; the ARRAY-HEADER. +;;; +;;; %WALK-DISPLACED-ARRAY-BACKPOINTERS is an especially nasty +;;; one: not only is it needed extremely rarely, which makes +;;; any thread safety bugs involving it look like rare random +;;; corruption, but because it walks the chain *upwards*, which +;;; may violate user expectations. + +(defun %save-displaced-array-backpointer (array data) + (flet ((purge (pointers) + (remove-if (lambda (value) + (or (not value) (eq array value))) + pointers + :key #'weak-pointer-value))) + ;; Add backpointer to the new data vector if it has a header. + (when (array-header-p data) + (setf (%array-displaced-from data) + (cons (make-weak-pointer array) + (purge (%array-displaced-from data))))) + ;; Remove old backpointer, if any. + (let ((old-data (%array-data-vector array))) + (when (and (neq data old-data) (array-header-p old-data)) + (setf (%array-displaced-from old-data) + (purge (%array-displaced-from old-data))))))) + +(defun %walk-displaced-array-backpointers (array new-length) + (dolist (p (%array-displaced-from array)) + (let ((from (weak-pointer-value p))) + (when (and from (eq array (%array-data-vector from))) + (let ((requires (+ (%array-available-elements from) + (%array-displacement from)))) + (unless (>= new-length requires) + ;; ANSI sayeth (ADJUST-ARRAY dictionary entry): + ;; + ;; "If A is displaced to B, the consequences are unspecified if B is + ;; adjusted in such a way that it no longer has enough elements to + ;; satisfy A. + ;; + ;; since we're hanging on a weak pointer here, we can't signal an + ;; error right now: the array that we're looking at might be + ;; garbage. Instead, we set all dimensions to zero so that next + ;; safe access to the displaced array will trap. Additionally, we + ;; save the original dimensions, so we can signal a more + ;; understandable error when the time comes. + (%walk-displaced-array-backpointers from 0) + (setf (%array-fill-pointer from) 0 + (%array-available-elements from) 0 + (%array-displaced-p from) (array-dimensions array)) + (dotimes (i (%array-rank from)) + (setf (%array-dimension from i) 0)))))))) + ;;; Fill in array header with the provided information, and return the array. (defun set-array-header (array data length fill-pointer displacement dimensions - &optional displacedp) + displacedp newp) + (if newp + (setf (%array-displaced-from array) nil) + (%walk-displaced-array-backpointers array length)) + (when displacedp + (%save-displaced-array-backpointer array data)) (setf (%array-data-vector array) data) (setf (%array-available-elements array) length) (cond (fill-pointer @@ -957,53 +1145,71 @@ of specialized arrays is supported." (setf (%array-dimension array 0) dimensions)) (setf (%array-displaced-p array) displacedp) array) + +;;; User visible extension +(declaim (ftype (function (array) (values (simple-array * (*)) &optional)) + array-storage-vector)) +(defun array-storage-vector (array) + "Returns the underlying storage vector of ARRAY, which must be a non-displaced array. + +In SBCL, if ARRAY is a of type \(SIMPLE-ARRAY * \(*)), it is its own storage +vector. Multidimensional arrays, arrays with fill pointers, and adjustable +arrays have an underlying storage vector with the same ARRAY-ELEMENT-TYPE as +ARRAY, which this function returns. + +Important note: the underlying vector is an implementation detail. Even though +this function exposes it, changes in the implementation may cause this +function to be removed without further warning." + ;; KLUDGE: Without TRULY-THE the system is not smart enough to figure out that + ;; the return value is always of the known type. + (truly-the (simple-array * (*)) + (if (array-header-p array) + (if (%array-displaced-p array) + (error "~S cannot be used with displaced arrays. Use ~S instead." + 'array-storage-vector 'array-displacement) + (%array-data-vector array)) + array))) -;;;; ZAP-ARRAY-DATA for ADJUST-ARRAY -;;; a temporary to be used when OLD-DATA and NEW-DATA are EQ. -;;; KLUDGE: Boy, DYNAMIC-EXTENT would be nice. This is rebound -;;; to length zero array in each new thread. -;;; -;;; DX is probably a bad idea, because a with a big array it would -;;; be fairly easy to blow the stack. -;;; -;;; Rebound per thread. -(defvar *zap-array-data-temp* (make-array 1000 :initial-element t)) - -(defun zap-array-data-temp (length element-type initial-element - initial-element-p) - (declare (fixnum length)) - (when (> length (the fixnum (length *zap-array-data-temp*))) - (setf *zap-array-data-temp* - (make-array length :initial-element t))) - (when initial-element-p - (unless (typep initial-element element-type) - (error "~S can't be used to initialize an array of type ~S." - initial-element element-type)) - (fill (the simple-vector *zap-array-data-temp*) initial-element - :end length)) - *zap-array-data-temp*) +;;;; ZAP-ARRAY-DATA for ADJUST-ARRAY ;;; This does the grinding work for ADJUST-ARRAY. It zaps the data ;;; from the OLD-DATA in an arrangement specified by the OLD-DIMS to ;;; the NEW-DATA in an arrangement specified by the NEW-DIMS. OFFSET ;;; is a displaced offset to be added to computed indices of OLD-DATA. -;;; NEW-LENGTH, ELEMENT-TYPE, INITIAL-ELEMENT, and INITIAL-ELEMENT-P -;;; are used when OLD-DATA and NEW-DATA are EQ; in this case, a -;;; temporary must be used and filled appropriately. When OLD-DATA and -;;; NEW-DATA are not EQ, NEW-DATA has already been filled with any -;;; specified initial-element. (defun zap-array-data (old-data old-dims offset new-data new-dims new-length element-type initial-element initial-element-p) - (declare (list old-dims new-dims)) - (setq old-dims (nreverse old-dims)) - (setq new-dims (reverse new-dims)) - (if (eq old-data new-data) - (let ((temp (zap-array-data-temp new-length element-type - initial-element initial-element-p))) - (zap-array-data-aux old-data old-dims offset temp new-dims) - (dotimes (i new-length) (setf (aref new-data i) (aref temp i)))) - (zap-array-data-aux old-data old-dims offset new-data new-dims))) + (declare (list old-dims new-dims) + (fixnum new-length)) + ;; OLD-DIMS comes from array-dimensions, which returns a fresh list + ;; at least in SBCL. + ;; NEW-DIMS comes from the user. + (setf old-dims (nreverse old-dims) + new-dims (reverse new-dims)) + (cond ((eq old-data new-data) + ;; NEW-LENGTH, ELEMENT-TYPE, INITIAL-ELEMENT, and + ;; INITIAL-ELEMENT-P are used when OLD-DATA and NEW-DATA are + ;; EQ; in this case, a temporary must be used and filled + ;; appropriately. specified initial-element. + (when initial-element-p + ;; FIXME: transforming this TYPEP to someting a bit faster + ;; would be a win... + (unless (typep initial-element element-type) + (error "~S can't be used to initialize an array of type ~S." + initial-element element-type))) + (let ((temp (if initial-element-p + (make-array new-length :initial-element initial-element) + (make-array new-length)))) + (declare (simple-vector temp)) + (zap-array-data-aux old-data old-dims offset temp new-dims) + (dotimes (i new-length) + (setf (aref new-data i) (aref temp i))) + ;; Kill the temporary vector to prevent garbage retention. + (%shrink-vector temp 0))) + (t + ;; When OLD-DATA and NEW-DATA are not EQ, NEW-DATA has + ;; already been filled with any + (zap-array-data-aux old-data old-dims offset new-data new-dims)))) (defun zap-array-data-aux (old-data old-dims offset new-data new-dims) (declare (fixnum offset))