src/compiler/array-tran.lisp

   1 ;;;; array-specific optimizers and transforms
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   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.
  11
  12 (in-package "SB!C")
  13 \f
  14 ;;;; utilities for optimizing array operations
  15
  16 ;;; Return UPGRADED-ARRAY-ELEMENT-TYPE for LVAR, or do
  17 ;;; GIVE-UP-IR1-TRANSFORM if the upgraded element type can't be
  18 ;;; determined.
  19 (defun upgraded-element-type-specifier-or-give-up (lvar)
  20   (let* ((element-ctype (extract-upgraded-element-type lvar))
  21          (element-type-specifier (type-specifier element-ctype)))
  22     (if (eq element-type-specifier '*)
  23         (give-up-ir1-transform
  24          "upgraded array element type not known at compile time")
  25         element-type-specifier)))
  26
  27 ;;; Array access functions return an object from the array, hence its type is
  28 ;;; going to be the array upgraded element type. Secondary return value is the
  29 ;;; known supertype of the upgraded-array-element-type, if if the exact
  30 ;;; U-A-E-T is not known. (If it is NIL, the primary return value is as good
  31 ;;; as it gets.)
  32 (defun extract-upgraded-element-type (array)
  33   (let ((type (lvar-type array)))
  34     (cond
  35       ;; Note that this IF mightn't be satisfied even if the runtime
  36       ;; value is known to be a subtype of some specialized ARRAY, because
  37       ;; we can have values declared e.g. (AND SIMPLE-VECTOR UNKNOWN-TYPE),
  38       ;; which are represented in the compiler as INTERSECTION-TYPE, not
  39       ;; array type.
  40       ((array-type-p type)
  41        (values (array-type-specialized-element-type type) nil))
  42       ;; fix for bug #396. This type logic corresponds to the special case for
  43       ;; strings in HAIRY-DATA-VECTOR-REF (generic/vm-tran.lisp)
  44       ((csubtypep type (specifier-type 'string))
  45        (cond
  46          ((csubtypep type (specifier-type '(array character (*))))
  47           (values (specifier-type 'character) nil))
  48          #!+sb-unicode
  49          ((csubtypep type (specifier-type '(array base-char (*))))
  50           (values (specifier-type 'base-char) nil))
  51          ((csubtypep type (specifier-type '(array nil (*))))
  52           (values *empty-type* nil))
  53          (t
  54           ;; See KLUDGE below.
  55           (values *wild-type* (specifier-type 'character)))))
  56       (t
  57        ;; KLUDGE: there is no good answer here, but at least
  58        ;; *wild-type* won't cause HAIRY-DATA-VECTOR-{REF,SET} to be
  59        ;; erroneously optimized (see generic/vm-tran.lisp) -- CSR,
  60        ;; 2002-08-21
  61        (values *wild-type* nil)))))
  62
  63 (defun extract-declared-element-type (array)
  64   (let ((type (lvar-type array)))
  65     (if (array-type-p type)
  66         (array-type-element-type type)
  67         *wild-type*)))
  68
  69 ;;; The ``new-value'' for array setters must fit in the array, and the
  70 ;;; return type is going to be the same as the new-value for SETF
  71 ;;; functions.
  72 (defun assert-new-value-type (new-value array)
  73   (let ((type (lvar-type array)))
  74     (when (array-type-p type)
  75       (assert-lvar-type
  76        new-value
  77        (array-type-specialized-element-type type)
  78        (lexenv-policy (node-lexenv (lvar-dest new-value))))))
  79   (lvar-type new-value))
  80
  81 (defun assert-array-complex (array)
  82   (assert-lvar-type
  83    array
  84    (make-array-type :complexp t
  85                     :element-type *wild-type*)
  86    (lexenv-policy (node-lexenv (lvar-dest array))))
  87   nil)
  88
  89 ;;; Return true if ARG is NIL, or is a constant-lvar whose
  90 ;;; value is NIL, false otherwise.
  91 (defun unsupplied-or-nil (arg)
  92   (declare (type (or lvar null) arg))
  93   (or (not arg)
  94       (and (constant-lvar-p arg)
  95            (not (lvar-value arg)))))
  96 \f
  97 ;;;; DERIVE-TYPE optimizers
  98
  99 ;;; Array operations that use a specific number of indices implicitly
 100 ;;; assert that the array is of that rank.
 101 (defun assert-array-rank (array rank)
 102   (assert-lvar-type
 103    array
 104    (specifier-type `(array * ,(make-list rank :initial-element '*)))
 105    (lexenv-policy (node-lexenv (lvar-dest array)))))
 106
 107 (defun derive-aref-type (array)
 108   (multiple-value-bind (uaet other) (extract-upgraded-element-type array)
 109     (or other uaet)))
 110
 111 (defoptimizer (array-in-bounds-p derive-type) ((array &rest indices))
 112   (assert-array-rank array (length indices))
 113   *universal-type*)
 114
 115 (defoptimizer (aref derive-type) ((array &rest indices) node)
 116   (assert-array-rank array (length indices))
 117   (derive-aref-type array))
 118
 119 (defoptimizer (%aset derive-type) ((array &rest stuff))
 120   (assert-array-rank array (1- (length stuff)))
 121   (assert-new-value-type (car (last stuff)) array))
 122
 123 (macrolet ((define (name)
 124              `(defoptimizer (,name derive-type) ((array index))
 125                 (derive-aref-type array))))
 126   (define hairy-data-vector-ref)
 127   (define hairy-data-vector-ref/check-bounds)
 128   (define data-vector-ref))
 129
 130 #!+(or x86 x86-64)
 131 (defoptimizer (data-vector-ref-with-offset derive-type) ((array index offset))
 132   (derive-aref-type array))
 133
 134 (macrolet ((define (name)
 135              `(defoptimizer (,name derive-type) ((array index new-value))
 136                 (assert-new-value-type new-value array))))
 137   (define hairy-data-vector-set)
 138   (define hairy-data-vector-set/check-bounds)
 139   (define data-vector-set))
 140
 141 #!+(or x86 x86-64)
 142 (defoptimizer (data-vector-set-with-offset derive-type) ((array index offset new-value))
 143   (assert-new-value-type new-value array))
 144
 145 ;;; Figure out the type of the data vector if we know the argument
 146 ;;; element type.
 147 (defun derive-%with-array-data/mumble-type (array)
 148   (let ((atype (lvar-type array)))
 149     (when (array-type-p atype)
 150       (specifier-type
 151        `(simple-array ,(type-specifier
 152                         (array-type-specialized-element-type atype))
 153                       (*))))))
 154 (defoptimizer (%with-array-data derive-type) ((array start end))
 155   (derive-%with-array-data/mumble-type array))
 156 (defoptimizer (%with-array-data/fp derive-type) ((array start end))
 157   (derive-%with-array-data/mumble-type array))
 158
 159 (defoptimizer (array-row-major-index derive-type) ((array &rest indices))
 160   (assert-array-rank array (length indices))
 161   *universal-type*)
 162
 163 (defoptimizer (row-major-aref derive-type) ((array index))
 164   (derive-aref-type array))
 165
 166 (defoptimizer (%set-row-major-aref derive-type) ((array index new-value))
 167   (assert-new-value-type new-value array))
 168
 169 (defoptimizer (make-array derive-type)
 170               ((dims &key initial-element element-type initial-contents
 171                 adjustable fill-pointer displaced-index-offset displaced-to))
 172   (let ((simple (and (unsupplied-or-nil adjustable)
 173                      (unsupplied-or-nil displaced-to)
 174                      (unsupplied-or-nil fill-pointer))))
 175     (or (careful-specifier-type
 176          `(,(if simple 'simple-array 'array)
 177             ,(cond ((not element-type) t)
 178                    ((constant-lvar-p element-type)
 179                     (let ((ctype (careful-specifier-type
 180                                   (lvar-value element-type))))
 181                       (cond
 182                         ((or (null ctype) (unknown-type-p ctype)) '*)
 183                         (t (sb!xc:upgraded-array-element-type
 184                             (lvar-value element-type))))))
 185                    (t
 186                     '*))
 187             ,(cond ((constant-lvar-p dims)
 188                     (let* ((val (lvar-value dims))
 189                            (cdims (if (listp val) val (list val))))
 190                       (if simple
 191                           cdims
 192                           (length cdims))))
 193                    ((csubtypep (lvar-type dims)
 194                                (specifier-type 'integer))
 195                     '(*))
 196                    (t
 197                     '*))))
 198         (specifier-type 'array))))
 199
 200 ;;; Complex array operations should assert that their array argument
 201 ;;; is complex.  In SBCL, vectors with fill-pointers are complex.
 202 (defoptimizer (fill-pointer derive-type) ((vector))
 203   (assert-array-complex vector))
 204 (defoptimizer (%set-fill-pointer derive-type) ((vector index))
 205   (declare (ignorable index))
 206   (assert-array-complex vector))
 207
 208 (defoptimizer (vector-push derive-type) ((object vector))
 209   (declare (ignorable object))
 210   (assert-array-complex vector))
 211 (defoptimizer (vector-push-extend derive-type)
 212     ((object vector &optional index))
 213   (declare (ignorable object index))
 214   (assert-array-complex vector))
 215 (defoptimizer (vector-pop derive-type) ((vector))
 216   (assert-array-complex vector))
 217 \f
 218 ;;;; constructors
 219
 220 ;;; Convert VECTOR into a MAKE-ARRAY followed by SETFs of all the
 221 ;;; elements.
 222 (define-source-transform vector (&rest elements)
 223   (let ((len (length elements))
 224         (n -1))
 225     (once-only ((n-vec `(make-array ,len)))
 226       `(progn
 227          ,@(mapcar (lambda (el)
 228                      (once-only ((n-val el))
 229                        `(locally (declare (optimize (safety 0)))
 230                           (setf (svref ,n-vec ,(incf n)) ,n-val))))
 231                    elements)
 232          ,n-vec))))
 233
 234 ;;; Just convert it into a MAKE-ARRAY.
 235 (deftransform make-string ((length &key
 236                                    (element-type 'character)
 237                                    (initial-element
 238                                     #.*default-init-char-form*)))
 239   `(the simple-string (make-array (the index length)
 240                        :element-type element-type
 241                        ,@(when initial-element
 242                            '(:initial-element initial-element)))))
 243
 244 (deftransform make-array ((dims &key initial-element element-type
 245                                      adjustable fill-pointer)
 246                           (t &rest *))
 247   (when (null initial-element)
 248     (give-up-ir1-transform))
 249   (let* ((eltype (cond ((not element-type) t)
 250                        ((not (constant-lvar-p element-type))
 251                         (give-up-ir1-transform
 252                          "ELEMENT-TYPE is not constant."))
 253                        (t
 254                         (lvar-value element-type))))
 255          (eltype-type (ir1-transform-specifier-type eltype))
 256          (saetp (find-if (lambda (saetp)
 257                            (csubtypep eltype-type (sb!vm:saetp-ctype saetp)))
 258                          sb!vm:*specialized-array-element-type-properties*))
 259          (creation-form `(make-array dims
 260                           :element-type ',(type-specifier (sb!vm:saetp-ctype saetp))
 261                           ,@(when fill-pointer
 262                                   '(:fill-pointer fill-pointer))
 263                           ,@(when adjustable
 264                                   '(:adjustable adjustable)))))
 265
 266     (unless saetp
 267       (give-up-ir1-transform "ELEMENT-TYPE not found in *SAETP*: ~S" eltype))
 268
 269     (cond ((and (constant-lvar-p initial-element)
 270                 (eql (lvar-value initial-element)
 271                      (sb!vm:saetp-initial-element-default saetp)))
 272            creation-form)
 273           (t
 274            ;; error checking for target, disabled on the host because
 275            ;; (CTYPE-OF #\Null) is not possible.
 276            #-sb-xc-host
 277            (when (constant-lvar-p initial-element)
 278              (let ((value (lvar-value initial-element)))
 279                (cond
 280                  ((not (ctypep value (sb!vm:saetp-ctype saetp)))
 281                   ;; this case will cause an error at runtime, so we'd
 282                   ;; better WARN about it now.
 283                   (warn 'array-initial-element-mismatch
 284                         :format-control "~@<~S is not a ~S (which is the ~
 285                                          ~S of ~S).~@:>"
 286                         :format-arguments
 287                         (list
 288                          value
 289                          (type-specifier (sb!vm:saetp-ctype saetp))
 290                          'upgraded-array-element-type
 291                          eltype)))
 292                  ((not (ctypep value eltype-type))
 293                   ;; this case will not cause an error at runtime, but
 294                   ;; it's still worth STYLE-WARNing about.
 295                   (compiler-style-warn "~S is not a ~S."
 296                                        value eltype)))))
 297            `(let ((array ,creation-form))
 298              (multiple-value-bind (vector)
 299                  (%data-vector-and-index array 0)
 300                (fill vector initial-element))
 301              array)))))
 302
 303 ;;; The integer type restriction on the length ensures that it will be
 304 ;;; a vector. The lack of :ADJUSTABLE, :FILL-POINTER, and
 305 ;;; :DISPLACED-TO keywords ensures that it will be simple; the lack of
 306 ;;; :INITIAL-ELEMENT relies on another transform to deal with that
 307 ;;; kind of initialization efficiently.
 308 (deftransform make-array ((length &key element-type)
 309                           (integer &rest *))
 310   (let* ((eltype (cond ((not element-type) t)
 311                        ((not (constant-lvar-p element-type))
 312                         (give-up-ir1-transform
 313                          "ELEMENT-TYPE is not constant."))
 314                        (t
 315                         (lvar-value element-type))))
 316          (len (if (constant-lvar-p length)
 317                   (lvar-value length)
 318                   '*))
 319          (eltype-type (ir1-transform-specifier-type eltype))
 320          (result-type-spec
 321           `(simple-array
 322             ,(if (unknown-type-p eltype-type)
 323                  (give-up-ir1-transform
 324                   "ELEMENT-TYPE is an unknown type: ~S" eltype)
 325                  (sb!xc:upgraded-array-element-type eltype))
 326             (,len)))
 327          (saetp (find-if (lambda (saetp)
 328                            (csubtypep eltype-type (sb!vm:saetp-ctype saetp)))
 329                          sb!vm:*specialized-array-element-type-properties*)))
 330     (unless saetp
 331       (give-up-ir1-transform
 332        "cannot open-code creation of ~S" result-type-spec))
 333     #-sb-xc-host
 334     (unless (ctypep (sb!vm:saetp-initial-element-default saetp) eltype-type)
 335       ;; This situation arises e.g. in (MAKE-ARRAY 4 :ELEMENT-TYPE
 336       ;; '(INTEGER 1 5)) ANSI's definition of MAKE-ARRAY says "If
 337       ;; INITIAL-ELEMENT is not supplied, the consequences of later
 338       ;; reading an uninitialized element of new-array are undefined,"
 339       ;; so this could be legal code as long as the user plans to
 340       ;; write before he reads, and if he doesn't we're free to do
 341       ;; anything we like. But in case the user doesn't know to write
 342       ;; elements before he reads elements (or to read manuals before
 343       ;; he writes code:-), we'll signal a STYLE-WARNING in case he
 344       ;; didn't realize this.
 345       (compiler-style-warn "The default initial element ~S is not a ~S."
 346                            (sb!vm:saetp-initial-element-default saetp)
 347                            eltype))
 348     (let* ((n-bits-per-element (sb!vm:saetp-n-bits saetp))
 349            (typecode (sb!vm:saetp-typecode saetp))
 350            (n-pad-elements (sb!vm:saetp-n-pad-elements saetp))
 351            (padded-length-form (if (zerop n-pad-elements)
 352                                    'length
 353                                    `(+ length ,n-pad-elements)))
 354            (n-words-form
 355             (cond
 356               ((= n-bits-per-element 0) 0)
 357               ((>= n-bits-per-element sb!vm:n-word-bits)
 358                `(* ,padded-length-form
 359                  (the fixnum ; i.e., not RATIO
 360                    ,(/ n-bits-per-element sb!vm:n-word-bits))))
 361               (t
 362                (let ((n-elements-per-word (/ sb!vm:n-word-bits
 363                                              n-bits-per-element)))
 364                  (declare (type index n-elements-per-word)) ; i.e., not RATIO
 365                  `(ceiling ,padded-length-form ,n-elements-per-word))))))
 366       (values
 367        `(truly-the ,result-type-spec
 368          (allocate-vector ,typecode length ,n-words-form))
 369        '((declare (type index length)))))))
 370
 371 ;;; The list type restriction does not ensure that the result will be a
 372 ;;; multi-dimensional array. But the lack of adjustable, fill-pointer,
 373 ;;; and displaced-to keywords ensures that it will be simple.
 374 ;;;
 375 ;;; FIXME: should we generalize this transform to non-simple (though
 376 ;;; non-displaced-to) arrays, given that we have %WITH-ARRAY-DATA to
 377 ;;; deal with those? Maybe when the DEFTRANSFORM
 378 ;;; %DATA-VECTOR-AND-INDEX in the VECTOR case problem is solved? --
 379 ;;; CSR, 2002-07-01
 380 (deftransform make-array ((dims &key element-type)
 381                           (list &rest *))
 382   (unless (or (null element-type) (constant-lvar-p element-type))
 383     (give-up-ir1-transform
 384      "The element-type is not constant; cannot open code array creation."))
 385   (unless (constant-lvar-p dims)
 386     (give-up-ir1-transform
 387      "The dimension list is not constant; cannot open code array creation."))
 388   (let ((dims (lvar-value dims)))
 389     (unless (every #'integerp dims)
 390       (give-up-ir1-transform
 391        "The dimension list contains something other than an integer: ~S"
 392        dims))
 393     (if (= (length dims) 1)
 394         `(make-array ',(car dims)
 395                      ,@(when element-type
 396                          '(:element-type element-type)))
 397         (let* ((total-size (reduce #'* dims))
 398                (rank (length dims))
 399                (spec `(simple-array
 400                        ,(cond ((null element-type) t)
 401                               ((and (constant-lvar-p element-type)
 402                                     (ir1-transform-specifier-type
 403                                      (lvar-value element-type)))
 404                                (sb!xc:upgraded-array-element-type
 405                                 (lvar-value element-type)))
 406                               (t '*))
 407                            ,(make-list rank :initial-element '*))))
 408           `(let ((header (make-array-header sb!vm:simple-array-widetag ,rank)))
 409              (setf (%array-fill-pointer header) ,total-size)
 410              (setf (%array-fill-pointer-p header) nil)
 411              (setf (%array-available-elements header) ,total-size)
 412              (setf (%array-data-vector header)
 413                    (make-array ,total-size
 414                                ,@(when element-type
 415                                    '(:element-type element-type))))
 416              (setf (%array-displaced-p header) nil)
 417              ,@(let ((axis -1))
 418                  (mapcar (lambda (dim)
 419                            `(setf (%array-dimension header ,(incf axis))
 420                                   ,dim))
 421                          dims))
 422              (truly-the ,spec header))))))
 423 \f
 424 ;;;; miscellaneous properties of arrays
 425
 426 ;;; Transforms for various array properties. If the property is know
 427 ;;; at compile time because of a type spec, use that constant value.
 428
 429 ;;; Most of this logic may end up belonging in code/late-type.lisp;
 430 ;;; however, here we also need the -OR-GIVE-UP for the transforms, and
 431 ;;; maybe this is just too sloppy for actual type logic.  -- CSR,
 432 ;;; 2004-02-18
 433 (defun array-type-dimensions-or-give-up (type)
 434   (typecase type
 435     (array-type (array-type-dimensions type))
 436     (union-type
 437      (let ((types (union-type-types type)))
 438        ;; there are at least two types, right?
 439        (aver (> (length types) 1))
 440        (let ((result (array-type-dimensions-or-give-up (car types))))
 441          (dolist (type (cdr types) result)
 442            (unless (equal (array-type-dimensions-or-give-up type) result)
 443              (give-up-ir1-transform))))))
 444     ;; FIXME: intersection type [e.g. (and (array * (*)) (satisfies foo)) ]
 445     (t (give-up-ir1-transform))))
 446
 447 (defun conservative-array-type-complexp (type)
 448   (typecase type
 449     (array-type (array-type-complexp type))
 450     (union-type
 451      (let ((types (union-type-types type)))
 452        (aver (> (length types) 1))
 453        (let ((result (conservative-array-type-complexp (car types))))
 454          (dolist (type (cdr types) result)
 455            (unless (eq (conservative-array-type-complexp type) result)
 456              (return-from conservative-array-type-complexp :maybe))))))
 457     ;; FIXME: intersection type
 458     (t :maybe)))
 459
 460 ;;; If we can tell the rank from the type info, use it instead.
 461 (deftransform array-rank ((array))
 462   (let ((array-type (lvar-type array)))
 463     (let ((dims (array-type-dimensions-or-give-up array-type)))
 464       (if (not (listp dims))
 465           (give-up-ir1-transform
 466            "The array rank is not known at compile time: ~S"
 467            dims)
 468           (length dims)))))
 469
 470 ;;; If we know the dimensions at compile time, just use it. Otherwise,
 471 ;;; if we can tell that the axis is in bounds, convert to
 472 ;;; %ARRAY-DIMENSION (which just indirects the array header) or length
 473 ;;; (if it's simple and a vector).
 474 (deftransform array-dimension ((array axis)
 475                                (array index))
 476   (unless (constant-lvar-p axis)
 477     (give-up-ir1-transform "The axis is not constant."))
 478   (let ((array-type (lvar-type array))
 479         (axis (lvar-value axis)))
 480     (let ((dims (array-type-dimensions-or-give-up array-type)))
 481       (unless (listp dims)
 482         (give-up-ir1-transform
 483          "The array dimensions are unknown; must call ARRAY-DIMENSION at runtime."))
 484       (unless (> (length dims) axis)
 485         (abort-ir1-transform "The array has dimensions ~S, ~W is too large."
 486                              dims
 487                              axis))
 488       (let ((dim (nth axis dims)))
 489         (cond ((integerp dim)
 490                dim)
 491               ((= (length dims) 1)
 492                (ecase (conservative-array-type-complexp array-type)
 493                  ((t)
 494                   '(%array-dimension array 0))
 495                  ((nil)
 496                   '(length array))
 497                  ((:maybe)
 498                   (give-up-ir1-transform
 499                    "can't tell whether array is simple"))))
 500               (t
 501                '(%array-dimension array axis)))))))
 502
 503 ;;; If the length has been declared and it's simple, just return it.
 504 (deftransform length ((vector)
 505                       ((simple-array * (*))))
 506   (let ((type (lvar-type vector)))
 507     (let ((dims (array-type-dimensions-or-give-up type)))
 508       (unless (and (listp dims) (integerp (car dims)))
 509         (give-up-ir1-transform
 510          "Vector length is unknown, must call LENGTH at runtime."))
 511       (car dims))))
 512
 513 ;;; All vectors can get their length by using VECTOR-LENGTH. If it's
 514 ;;; simple, it will extract the length slot from the vector. It it's
 515 ;;; complex, it will extract the fill pointer slot from the array
 516 ;;; header.
 517 (deftransform length ((vector) (vector))
 518   '(vector-length vector))
 519
 520 ;;; If a simple array with known dimensions, then VECTOR-LENGTH is a
 521 ;;; compile-time constant.
 522 (deftransform vector-length ((vector))
 523   (let ((vtype (lvar-type vector)))
 524     (let ((dim (first (array-type-dimensions-or-give-up vtype))))
 525       (when (eq dim '*)
 526         (give-up-ir1-transform))
 527       (when (conservative-array-type-complexp vtype)
 528         (give-up-ir1-transform))
 529       dim)))
 530
 531 ;;; Again, if we can tell the results from the type, just use it.
 532 ;;; Otherwise, if we know the rank, convert into a computation based
 533 ;;; on array-dimension. We can wrap a TRULY-THE INDEX around the
 534 ;;; multiplications because we know that the total size must be an
 535 ;;; INDEX.
 536 (deftransform array-total-size ((array)
 537                                 (array))
 538   (let ((array-type (lvar-type array)))
 539     (let ((dims (array-type-dimensions-or-give-up array-type)))
 540       (unless (listp dims)
 541         (give-up-ir1-transform "can't tell the rank at compile time"))
 542       (if (member '* dims)
 543           (do ((form 1 `(truly-the index
 544                                    (* (array-dimension array ,i) ,form)))
 545                (i 0 (1+ i)))
 546               ((= i (length dims)) form))
 547           (reduce #'* dims)))))
 548
 549 ;;; Only complex vectors have fill pointers.
 550 (deftransform array-has-fill-pointer-p ((array))
 551   (let ((array-type (lvar-type array)))
 552     (let ((dims (array-type-dimensions-or-give-up array-type)))
 553       (if (and (listp dims) (not (= (length dims) 1)))
 554           nil
 555           (ecase (conservative-array-type-complexp array-type)
 556             ((t)
 557              t)
 558             ((nil)
 559              nil)
 560             ((:maybe)
 561              (give-up-ir1-transform
 562               "The array type is ambiguous; must call ~
 563                ARRAY-HAS-FILL-POINTER-P at runtime.")))))))
 564
 565 ;;; Primitive used to verify indices into arrays. If we can tell at
 566 ;;; compile-time or we are generating unsafe code, don't bother with
 567 ;;; the VOP.
 568 (deftransform %check-bound ((array dimension index) * * :node node)
 569   (cond ((policy node (= insert-array-bounds-checks 0))
 570          'index)
 571         ((not (constant-lvar-p dimension))
 572          (give-up-ir1-transform))
 573         (t
 574          (let ((dim (lvar-value dimension)))
 575            ;; FIXME: Can SPEED > SAFETY weaken this check to INTEGER?
 576            `(the (integer 0 (,dim)) index)))))
 577 \f
 578 ;;;; WITH-ARRAY-DATA
 579
 580 ;;; This checks to see whether the array is simple and the start and
 581 ;;; end are in bounds. If so, it proceeds with those values.
 582 ;;; Otherwise, it calls %WITH-ARRAY-DATA. Note that %WITH-ARRAY-DATA
 583 ;;; may be further optimized.
 584 ;;;
 585 ;;; Given any ARRAY, bind DATA-VAR to the array's data vector and
 586 ;;; START-VAR and END-VAR to the start and end of the designated
 587 ;;; portion of the data vector. SVALUE and EVALUE are any start and
 588 ;;; end specified to the original operation, and are factored into the
 589 ;;; bindings of START-VAR and END-VAR. OFFSET-VAR is the cumulative
 590 ;;; offset of all displacements encountered, and does not include
 591 ;;; SVALUE.
 592 ;;;
 593 ;;; When FORCE-INLINE is set, the underlying %WITH-ARRAY-DATA form is
 594 ;;; forced to be inline, overriding the ordinary judgment of the
 595 ;;; %WITH-ARRAY-DATA DEFTRANSFORMs. Ordinarily the DEFTRANSFORMs are
 596 ;;; fairly picky about their arguments, figuring that if you haven't
 597 ;;; bothered to get all your ducks in a row, you probably don't care
 598 ;;; that much about speed anyway! But in some cases it makes sense to
 599 ;;; do type testing inside %WITH-ARRAY-DATA instead of outside, and
 600 ;;; the DEFTRANSFORM can't tell that that's going on, so it can make
 601 ;;; sense to use FORCE-INLINE option in that case.
 602 (def!macro with-array-data (((data-var array &key offset-var)
 603                              (start-var &optional (svalue 0))
 604                              (end-var &optional (evalue nil))
 605                              &key force-inline check-fill-pointer)
 606                             &body forms
 607                             &environment env)
 608   (once-only ((n-array array)
 609               (n-svalue `(the index ,svalue))
 610               (n-evalue `(the (or index null) ,evalue)))
 611     (let ((check-bounds (policy env (plusp insert-array-bounds-checks))))
 612       `(multiple-value-bind (,data-var
 613                              ,start-var
 614                              ,end-var
 615                              ,@(when offset-var `(,offset-var)))
 616            (if (not (array-header-p ,n-array))
 617                (let ((,n-array ,n-array))
 618                  (declare (type (simple-array * (*)) ,n-array))
 619                  ,(once-only ((n-len (if check-fill-pointer
 620                                          `(length ,n-array)
 621                                          `(array-total-size ,n-array)))
 622                               (n-end `(or ,n-evalue ,n-len)))
 623                              (if check-bounds
 624                                  `(if (<= 0 ,n-svalue ,n-end ,n-len)
 625                                       (values ,n-array ,n-svalue ,n-end 0)
 626                                       ,(if check-fill-pointer
 627                                            `(sequence-bounding-indices-bad-error ,n-array ,n-svalue ,n-evalue)
 628                                            `(array-bounding-indices-bad-error ,n-array ,n-svalue ,n-evalue)))
 629                                  `(values ,n-array ,n-svalue ,n-end 0))))
 630                ,(if force-inline
 631                     `(%with-array-data-macro ,n-array ,n-svalue ,n-evalue
 632                                              :check-bounds ,check-bounds
 633                                              :check-fill-pointer ,check-fill-pointer)
 634                     (if check-fill-pointer
 635                         `(%with-array-data/fp ,n-array ,n-svalue ,n-evalue)
 636                         `(%with-array-data ,n-array ,n-svalue ,n-evalue))))
 637          ,@forms))))
 638
 639 ;;; This is the fundamental definition of %WITH-ARRAY-DATA, for use in
 640 ;;; DEFTRANSFORMs and DEFUNs.
 641 (def!macro %with-array-data-macro (array
 642                                    start
 643                                    end
 644                                    &key
 645                                    (element-type '*)
 646                                    check-bounds
 647                                    check-fill-pointer)
 648   (with-unique-names (size defaulted-end data cumulative-offset)
 649     `(let* ((,size ,(if check-fill-pointer
 650                         `(length ,array)
 651                         `(array-total-size ,array)))
 652             (,defaulted-end (or ,end ,size)))
 653        ,@(when check-bounds
 654                `((unless (<= ,start ,defaulted-end ,size)
 655                    ,(if check-fill-pointer
 656                         `(sequence-bounding-indices-bad-error ,array ,start ,end)
 657                         `(array-bounding-indices-bad-error ,array ,start ,end)))))
 658        (do ((,data ,array (%array-data-vector ,data))
 659             (,cumulative-offset 0
 660                                 (+ ,cumulative-offset
 661                                    (%array-displacement ,data))))
 662            ((not (array-header-p ,data))
 663             (values (the (simple-array ,element-type 1) ,data)
 664                     (the index (+ ,cumulative-offset ,start))
 665                     (the index (+ ,cumulative-offset ,defaulted-end))
 666                     (the index ,cumulative-offset)))
 667          (declare (type index ,cumulative-offset))))))
 668
 669 (defun transform-%with-array-data/muble (array node check-fill-pointer)
 670   (let ((element-type (upgraded-element-type-specifier-or-give-up array))
 671         (type (lvar-type array))
 672         (check-bounds (policy node (plusp insert-array-bounds-checks))))
 673     (if (and (array-type-p type)
 674              (not (array-type-complexp type))
 675              (listp (array-type-dimensions type))
 676              (not (null (cdr (array-type-dimensions type)))))
 677         ;; If it's a simple multidimensional array, then just return
 678         ;; its data vector directly rather than going through
 679         ;; %WITH-ARRAY-DATA-MACRO. SBCL doesn't generally generate
 680         ;; code that would use this currently, but we have encouraged
 681         ;; users to use WITH-ARRAY-DATA and we may use it ourselves at
 682         ;; some point in the future for optimized libraries or
 683         ;; similar.
 684         (if check-bounds
 685             `(let* ((data (truly-the (simple-array ,element-type (*))
 686                                      (%array-data-vector array)))
 687                     (len (length data))
 688                     (real-end (or end len)))
 689                (unless (<= 0 start data-end lend)
 690                  (sequence-bounding-indices-bad-error array start end))
 691                (values data 0 real-end 0))
 692             `(let ((data (truly-the (simple-array ,element-type (*))
 693                                     (%array-data-vector array))))
 694                (values data 0 (or end (length data)) 0)))
 695         `(%with-array-data-macro array start end
 696                                  :check-fill-pointer ,check-fill-pointer
 697                                  :check-bounds ,check-bounds
 698                                  :element-type ,element-type))))
 699
 700 ;; It might very well be reasonable to allow general ARRAY here, I
 701 ;; just haven't tried to understand the performance issues involved.
 702 ;; -- WHN, and also CSR 2002-05-26
 703 (deftransform %with-array-data ((array start end)
 704                                 ((or vector simple-array) index (or index null) t)
 705                                 *
 706                                 :node node
 707                                 :policy (> speed space))
 708   "inline non-SIMPLE-vector-handling logic"
 709   (transform-%with-array-data/muble array node nil))
 710 (deftransform %with-array-data/fp ((array start end)
 711                                 ((or vector simple-array) index (or index null) t)
 712                                 *
 713                                 :node node
 714                                 :policy (> speed space))
 715   "inline non-SIMPLE-vector-handling logic"
 716   (transform-%with-array-data/muble array node t))
 717 \f
 718 ;;;; array accessors
 719
 720 ;;; We convert all typed array accessors into AREF and %ASET with type
 721 ;;; assertions on the array.
 722 (macrolet ((define-bit-frob (reffer setter simplep)
 723              `(progn
 724                 (define-source-transform ,reffer (a &rest i)
 725                   `(aref (the (,',(if simplep 'simple-array 'array)
 726                                   bit
 727                                   ,(mapcar (constantly '*) i))
 728                            ,a) ,@i))
 729                 (define-source-transform ,setter (a &rest i)
 730                   `(%aset (the (,',(if simplep 'simple-array 'array)
 731                                    bit
 732                                    ,(cdr (mapcar (constantly '*) i)))
 733                             ,a) ,@i)))))
 734   (define-bit-frob sbit %sbitset t)
 735   (define-bit-frob bit %bitset nil))
 736 (macrolet ((define-frob (reffer setter type)
 737              `(progn
 738                 (define-source-transform ,reffer (a i)
 739                   `(aref (the ,',type ,a) ,i))
 740                 (define-source-transform ,setter (a i v)
 741                   `(%aset (the ,',type ,a) ,i ,v)))))
 742   (define-frob svref %svset simple-vector)
 743   (define-frob schar %scharset simple-string)
 744   (define-frob char %charset string))
 745
 746 (macrolet (;; This is a handy macro for computing the row-major index
 747            ;; given a set of indices. We wrap each index with a call
 748            ;; to %CHECK-BOUND to ensure that everything works out
 749            ;; correctly. We can wrap all the interior arithmetic with
 750            ;; TRULY-THE INDEX because we know the resultant
 751            ;; row-major index must be an index.
 752            (with-row-major-index ((array indices index &optional new-value)
 753                                   &rest body)
 754              `(let (n-indices dims)
 755                 (dotimes (i (length ,indices))
 756                   (push (make-symbol (format nil "INDEX-~D" i)) n-indices)
 757                   (push (make-symbol (format nil "DIM-~D" i)) dims))
 758                 (setf n-indices (nreverse n-indices))
 759                 (setf dims (nreverse dims))
 760                 `(lambda (,',array ,@n-indices
 761                                    ,@',(when new-value (list new-value)))
 762                    (let* (,@(let ((,index -1))
 763                               (mapcar (lambda (name)
 764                                         `(,name (array-dimension
 765                                                  ,',array
 766                                                  ,(incf ,index))))
 767                                       dims))
 768                             (,',index
 769                              ,(if (null dims)
 770                                   0
 771                                 (do* ((dims dims (cdr dims))
 772                                       (indices n-indices (cdr indices))
 773                                       (last-dim nil (car dims))
 774                                       (form `(%check-bound ,',array
 775                                                            ,(car dims)
 776                                                            ,(car indices))
 777                                             `(truly-the
 778                                               index
 779                                               (+ (truly-the index
 780                                                             (* ,form
 781                                                                ,last-dim))
 782                                                  (%check-bound
 783                                                   ,',array
 784                                                   ,(car dims)
 785                                                   ,(car indices))))))
 786                                     ((null (cdr dims)) form)))))
 787                      ,',@body)))))
 788
 789   ;; Just return the index after computing it.
 790   (deftransform array-row-major-index ((array &rest indices))
 791     (with-row-major-index (array indices index)
 792       index))
 793
 794   ;; Convert AREF and %ASET into a HAIRY-DATA-VECTOR-REF (or
 795   ;; HAIRY-DATA-VECTOR-SET) with the set of indices replaced with the an
 796   ;; expression for the row major index.
 797   (deftransform aref ((array &rest indices))
 798     (with-row-major-index (array indices index)
 799       (hairy-data-vector-ref array index)))
 800
 801   (deftransform %aset ((array &rest stuff))
 802     (let ((indices (butlast stuff)))
 803       (with-row-major-index (array indices index new-value)
 804         (hairy-data-vector-set array index new-value)))))
 805
 806 ;; For AREF of vectors we do the bounds checking in the callee. This
 807 ;; lets us do a significantly more efficient check for simple-arrays
 808 ;; without bloating the code. If we already know the type of the array
 809 ;; with sufficient precision, skip directly to DATA-VECTOR-REF.
 810 (deftransform aref ((array index) (t t) * :node node)
 811   (let* ((type (lvar-type array))
 812          (element-ctype (extract-upgraded-element-type array)))
 813     (cond
 814       ((and (array-type-p type)
 815             (null (array-type-complexp type))
 816             (not (eql element-ctype *wild-type*))
 817             (eql (length (array-type-dimensions type)) 1))
 818        (let* ((declared-element-ctype (extract-declared-element-type array))
 819               (bare-form
 820                `(data-vector-ref array
 821                  (%check-bound array (array-dimension array 0) index))))
 822          (if (type= declared-element-ctype element-ctype)
 823              bare-form
 824              `(the ,(type-specifier declared-element-ctype) ,bare-form))))
 825       ((policy node (zerop insert-array-bounds-checks))
 826        `(hairy-data-vector-ref array index))
 827       (t `(hairy-data-vector-ref/check-bounds array index)))))
 828
 829 (deftransform %aset ((array index new-value) (t t t) * :node node)
 830   (if (policy node (zerop insert-array-bounds-checks))
 831       `(hairy-data-vector-set array index new-value)
 832       `(hairy-data-vector-set/check-bounds array index new-value)))
 833
 834 ;;; But if we find out later that there's some useful type information
 835 ;;; available, switch back to the normal one to give other transforms
 836 ;;; a stab at it.
 837 (macrolet ((define (name transform-to extra extra-type)
 838              (declare (ignore extra-type))
 839              `(deftransform ,name ((array index ,@extra))
 840                 (let ((type (lvar-type array))
 841                       (element-type (extract-upgraded-element-type array)))
 842                   ;; If an element type has been declared, we want to
 843                   ;; use that information it for type checking (even
 844                   ;; if the access can't be optimized due to the array
 845                   ;; not being simple).
 846                   (when (and (eql element-type *wild-type*)
 847                              ;; This type logic corresponds to the special
 848                              ;; case for strings in HAIRY-DATA-VECTOR-REF
 849                              ;; (generic/vm-tran.lisp)
 850                              (not (csubtypep type (specifier-type 'simple-string))))
 851                     (when (or (not (array-type-p type))
 852                               ;; If it's a simple array, we might be able
 853                               ;; to inline the access completely.
 854                               (not (null (array-type-complexp type))))
 855                       (give-up-ir1-transform
 856                        "Upgraded element type of array is not known at compile time."))))
 857                 `(,',transform-to array
 858                                   (%check-bound array
 859                                                 (array-dimension array 0)
 860                                                 index)
 861                                   ,@',extra))))
 862   (define hairy-data-vector-ref/check-bounds
 863       hairy-data-vector-ref nil nil)
 864   (define hairy-data-vector-set/check-bounds
 865       hairy-data-vector-set (new-value) (*)))
 866
 867 ;;; Just convert into a HAIRY-DATA-VECTOR-REF (or
 868 ;;; HAIRY-DATA-VECTOR-SET) after checking that the index is inside the
 869 ;;; array total size.
 870 (deftransform row-major-aref ((array index))
 871   `(hairy-data-vector-ref array
 872                           (%check-bound array (array-total-size array) index)))
 873 (deftransform %set-row-major-aref ((array index new-value))
 874   `(hairy-data-vector-set array
 875                           (%check-bound array (array-total-size array) index)
 876                           new-value))
 877 \f
 878 ;;;; bit-vector array operation canonicalization
 879 ;;;;
 880 ;;;; We convert all bit-vector operations to have the result array
 881 ;;;; specified. This allows any result allocation to be open-coded,
 882 ;;;; and eliminates the need for any VM-dependent transforms to handle
 883 ;;;; these cases.
 884
 885 (macrolet ((def (fun)
 886              `(progn
 887                (deftransform ,fun ((bit-array-1 bit-array-2
 888                                                 &optional result-bit-array)
 889                                    (bit-vector bit-vector &optional null) *
 890                                    :policy (>= speed space))
 891                  `(,',fun bit-array-1 bit-array-2
 892                    (make-array (array-dimension bit-array-1 0) :element-type 'bit)))
 893                ;; If result is T, make it the first arg.
 894                (deftransform ,fun ((bit-array-1 bit-array-2 result-bit-array)
 895                                    (bit-vector bit-vector (eql t)) *)
 896                  `(,',fun bit-array-1 bit-array-2 bit-array-1)))))
 897   (def bit-and)
 898   (def bit-ior)
 899   (def bit-xor)
 900   (def bit-eqv)
 901   (def bit-nand)
 902   (def bit-nor)
 903   (def bit-andc1)
 904   (def bit-andc2)
 905   (def bit-orc1)
 906   (def bit-orc2))
 907
 908 ;;; Similar for BIT-NOT, but there is only one arg...
 909 (deftransform bit-not ((bit-array-1 &optional result-bit-array)
 910                        (bit-vector &optional null) *
 911                        :policy (>= speed space))
 912   '(bit-not bit-array-1
 913             (make-array (array-dimension bit-array-1 0) :element-type 'bit)))
 914 (deftransform bit-not ((bit-array-1 result-bit-array)
 915                        (bit-vector (eql t)))
 916   '(bit-not bit-array-1 bit-array-1))
 917 \f
 918 ;;; Pick off some constant cases.
 919 (defoptimizer (array-header-p derive-type) ((array))
 920   (let ((type (lvar-type array)))
 921     (cond ((not (array-type-p type))
 922            ;; FIXME: use analogue of ARRAY-TYPE-DIMENSIONS-OR-GIVE-UP
 923            nil)
 924           (t
 925            (let ((dims (array-type-dimensions type)))
 926              (cond ((csubtypep type (specifier-type '(simple-array * (*))))
 927                     ;; no array header
 928                     (specifier-type 'null))
 929                    ((and (listp dims) (/= (length dims) 1))
 930                     ;; multi-dimensional array, will have a header
 931                     (specifier-type '(eql t)))
 932                    ((eql (array-type-complexp type) t)
 933                     (specifier-type '(eql t)))
 934                    (t
 935                     nil)))))))