1 ;;;; implementation-dependent transforms
3 ;;;; This software is part of the SBCL system. See the README file for
6 ;;;; This software is derived from the CMU CL system, which was
7 ;;;; written at Carnegie Mellon University and released into the
8 ;;;; public domain. The software is in the public domain and is
9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
10 ;;;; files for more information.
17 ;;; FIXME: It would be good to implement SB!XC:DEFCONSTANT, and use
18 ;;; use that here, so that the compiler is born knowing this value.
19 ;;; FIXME: Add a comment telling whether this holds for all vectors
20 ;;; or only for vectors based on simple arrays (non-adjustable, etc.).
21 (defconstant vector-data-bit-offset
22 (* sb!vm:vector-data-offset sb!vm:word-bits))
24 ;;; We need to define these predicates, since the TYPEP source transform picks
25 ;;; whichever predicate was defined last when there are multiple predicates for
27 (def-source-transform short-float-p (x) `(single-float-p ,x))
29 (def-source-transform long-float-p (x) `(double-float-p ,x))
31 (def-source-transform compiled-function-p (x)
34 (def-source-transform char-int (x)
37 (deftransform abs ((x) (rational))
38 '(if (< x 0) (- x) x))
40 ;;; The layout is stored in slot 0.
41 (def-source-transform %instance-layout (x)
42 `(truly-the layout (%instance-ref ,x 0)))
43 (def-source-transform %set-instance-layout (x val)
44 `(%instance-set ,x 0 (the layout ,val)))
46 ;;;; character support
48 ;;; In our implementation there are really only BASE-CHARs.
49 (def-source-transform characterp (obj)
52 ;;;; simplifying HAIRY-DATA-VECTOR-REF and HAIRY-DATA-VECTOR-SET
54 (deftransform hairy-data-vector-ref ((array index) (array t) * :important t)
55 "avoid runtime dispatch on array element type"
56 (let ((element-ctype (extract-upgraded-element-type array)))
57 (declare (type ctype element-ctype))
58 (when (eq *wild-type* element-ctype)
59 (give-up-ir1-transform
60 "Upgraded element type of array is not known at compile time."))
61 ;; (The expansion here is basically a degenerate case of
62 ;; WITH-ARRAY-DATA. Since WITH-ARRAY-DATA is implemented as a
63 ;; macro, and macros aren't expanded in transform output, we have
64 ;; to hand-expand it ourselves.)
65 (let ((element-type-specifier (type-specifier element-ctype)))
66 `(multiple-value-bind (array index)
67 ;; FIXME: All this noise should move into a
68 ;; %DATA-VECTOR-AND-INDEX function, and there should be
69 ;; DEFTRANSFORMs for %DATA-VECTOR-AND-INDEX to optimize the
70 ;; function call away when the array is known to be simple,
71 ;; and to specialize to
72 ;; %DATA-VECTOR-AND-INDEX-IN-VECTOR-CASE when the array is
73 ;; known to have only one dimension.
74 (if (array-header-p array)
75 (%with-array-data array index nil)
77 (declare (type (simple-array ,element-type-specifier 1)
79 (%check-bound array 0 index)
80 (values array index)))
81 (declare (type (simple-array ,element-type-specifier 1) array))
82 (data-vector-ref array index)))))
84 (deftransform data-vector-ref ((array index)
86 (let ((array-type (continuation-type array)))
87 (unless (array-type-p array-type)
88 (give-up-ir1-transform))
89 (let ((dims (array-type-dimensions array-type)))
90 (when (or (atom dims) (= (length dims) 1))
91 (give-up-ir1-transform))
92 (let ((el-type (array-type-element-type array-type))
93 (total-size (if (member '* dims)
96 `(data-vector-ref (truly-the (simple-array ,(type-specifier el-type)
98 (%array-data-vector array))
101 (deftransform hairy-data-vector-set ((array index new-value)
105 "avoid runtime dispatch on array element type"
106 (let ((element-ctype (extract-upgraded-element-type array)))
107 (declare (type ctype element-ctype))
108 (when (eq *wild-type* element-ctype)
109 (give-up-ir1-transform
110 "Upgraded element type of array is not known at compile time."))
111 (let ((element-type-specifier (type-specifier element-ctype)))
112 `(multiple-value-bind (array index)
113 ;; FIXME: All this noise should move into a
114 ;; %DATA-VECTOR-AND-INDEX function, and there should be
115 ;; DEFTRANSFORMs for %DATA-VECTOR-AND-INDEX to optimize the
116 ;; function call away when the array is known to be simple,
117 ;; and to specialize to
118 ;; %DATA-VECTOR-AND-INDEX-IN-VECTOR-CASE when the array is
119 ;; known to have only one dimension.
120 (if (array-header-p array)
121 (%with-array-data array index nil)
123 (declare (type (simple-array ,element-type-specifier 1)
125 (%check-bound array 0 index)
126 (values array index)))
127 (data-vector-set (truly-the (simple-array ,element-type-specifier 1)
132 (deftransform data-vector-set ((array index new-value)
134 (let ((array-type (continuation-type array)))
135 (unless (array-type-p array-type)
136 (give-up-ir1-transform))
137 (let ((dims (array-type-dimensions array-type)))
138 (when (or (atom dims) (= (length dims) 1))
139 (give-up-ir1-transform))
140 (let ((el-type (array-type-element-type array-type))
141 (total-size (if (member '* dims)
144 `(data-vector-set (truly-the (simple-array ,(type-specifier el-type)
146 (%array-data-vector array))
150 ;;; transforms for getting at simple arrays of (UNSIGNED-BYTE N) when (< N 8)
152 ;;; FIXME: In CMU CL, these were commented out with #+NIL. Why? Should
153 ;;; we fix them or should we delete them? (Perhaps these definitions
154 ;;; predate the various DATA-VECTOR-REF-FOO VOPs which have
155 ;;; (:TRANSLATE DATA-VECTOR-REF), and are redundant now?)
159 (let ((elements-per-word (truncate sb!vm:word-bits bits)))
161 (deftransform data-vector-ref ((vector index)
163 `(multiple-value-bind (word bit)
164 (floor index ,',elements-per-word)
165 (ldb ,(ecase sb!vm:target-byte-order
166 (:little-endian '(byte ,bits (* bit ,bits)))
167 (:big-endian '(byte ,bits (- sb!vm:word-bits
168 (* (1+ bit) ,bits)))))
169 (%raw-bits vector (+ word sb!vm:vector-data-offset)))))
170 (deftransform data-vector-set ((vector index new-value)
172 `(multiple-value-bind (word bit)
173 (floor index ,',elements-per-word)
174 (setf (ldb ,(ecase sb!vm:target-byte-order
175 (:little-endian '(byte ,bits (* bit ,bits)))
177 '(byte ,bits (- sb!vm:word-bits
178 (* (1+ bit) ,bits)))))
179 (%raw-bits vector (+ word sb!vm:vector-data-offset)))
181 (frob simple-bit-vector 1)
182 (frob (simple-array (unsigned-byte 2) (*)) 2)
183 (frob (simple-array (unsigned-byte 4) (*)) 4))
185 ;;;; simple string transforms
187 ;;;; Note: CMU CL had more of these, including transforms for
188 ;;;; functions which cons. In SBCL, we've gotten rid of the transforms
189 ;;;; for functions which cons, since our GC overhead is sufficiently
190 ;;;; large that it doesn't seem worth it to try to economize on
191 ;;;; function call overhead or on the overhead of runtime type
192 ;;;; dispatch in AREF.
194 (deftransform subseq ((string start &optional (end nil))
195 (simple-string t &optional t))
196 `(let* ((length (- (or end (length string))
198 (result (make-string length)))
199 (declare (optimize (safety 0)))
200 (bit-bash-copy string
202 (+ (the index (* start sb!vm:byte-bits))
203 ,vector-data-bit-offset))
205 ,vector-data-bit-offset
206 (the index (* length sb!vm:byte-bits)))
209 (deftransform copy-seq ((seq) (simple-string))
210 `(let* ((length (length seq))
211 (res (make-string length)))
212 (declare (optimize (safety 0)))
214 ,vector-data-bit-offset
216 ,vector-data-bit-offset
217 (the index (* length sb!vm:byte-bits)))
220 (deftransform replace ((string1 string2 &key (start1 0) (start2 0)
222 (simple-string simple-string &rest t))
223 `(locally (declare (optimize (safety 0)))
224 (bit-bash-copy string2
226 (+ (the index (* start2 sb!vm:byte-bits))
227 ,vector-data-bit-offset))
230 (+ (the index (* start1 sb!vm:byte-bits))
231 ,vector-data-bit-offset))
233 (* (min (the index (- (or end1 (length string1))
235 (the index (- (or end2 (length string2))
240 (deftransform concatenate ((rtype &rest sequences)
241 (t &rest simple-string)
247 (dolist (seq sequences)
248 (declare (ignore seq))
249 (let ((n-seq (gensym))
252 (lets `(,n-length (the index (* (length ,n-seq) sb!vm:byte-bits))))
253 (all-lengths n-length)
254 (forms `(bit-bash-copy ,n-seq ,vector-data-bit-offset
257 (forms `(setq start (+ start ,n-length)))))
258 `(lambda (rtype ,@(args))
259 (declare (ignore rtype))
261 (res (make-string (truncate (the index (+ ,@(all-lengths)))
263 (start ,vector-data-bit-offset))
264 (declare (type index start ,@(all-lengths)))
268 ;;;; bit vector hackery
270 ;;; SIMPLE-BIT-VECTOR bit-array operations are transformed to a word loop that
271 ;;; does 32 bits at a time.
273 ;;; FIXME: This is a lot of repeatedly macroexpanded code. It should be a
274 ;;; function call instead. And do it with DEF-FROB instead of DOLIST.
275 (dolist (x '((bit-and 32bit-logical-and)
276 (bit-ior 32bit-logical-or)
277 (bit-xor 32bit-logical-xor)
278 (bit-eqv 32bit-logical-eqv)
279 (bit-nand 32bit-logical-nand)
280 (bit-nor 32bit-logical-nor)
281 (bit-andc1 32bit-logical-andc1)
282 (bit-andc2 32bit-logical-andc2)
283 (bit-orc1 32bit-logical-orc1)
284 (bit-orc2 32bit-logical-orc2)))
285 (destructuring-bind (bitfun wordfun) x
287 ((bit-array-1 bit-array-2 result-bit-array)
288 '(simple-bit-vector simple-bit-vector simple-bit-vector) '*
289 :eval-name t :node node :policy (>= speed space))
291 ,@(unless (policy node (zerop safety))
292 '((unless (= (length bit-array-1) (length bit-array-2)
293 (length result-bit-array))
294 (error "Argument and/or result bit arrays are not the same length:~
296 bit-array-1 bit-array-2 result-bit-array))))
297 (do ((index sb!vm:vector-data-offset (1+ index))
298 (end (+ sb!vm:vector-data-offset
300 (+ (length bit-array-1)
303 ((= index end) result-bit-array)
304 (declare (optimize (speed 3) (safety 0))
305 (type index index end))
306 (setf (%raw-bits result-bit-array index)
307 (,wordfun (%raw-bits bit-array-1 index)
308 (%raw-bits bit-array-2 index))))))))
310 (deftransform bit-not
311 ((bit-array result-bit-array)
312 (simple-bit-vector simple-bit-vector) *
313 :node node :policy (>= speed space))
315 ,@(unless (policy node (zerop safety))
316 '((unless (= (length bit-array)
317 (length result-bit-array))
318 (error "Argument and result bit arrays are not the same length:~
320 bit-array result-bit-array))))
321 (do ((index sb!vm:vector-data-offset (1+ index))
322 (end (+ sb!vm:vector-data-offset
324 (+ (length bit-array)
325 (1- sb!vm:word-bits)))
327 ((= index end) result-bit-array)
328 (declare (optimize (speed 3) (safety 0))
329 (type index index end))
330 (setf (%raw-bits result-bit-array index)
331 (32bit-logical-not (%raw-bits bit-array index))))))
333 ;;;; primitive translator for BYTE-BLT
335 (def-primitive-translator byte-blt (src src-start dst dst-start dst-end)
337 (src-start (* ,src-start sb!vm:byte-bits))
339 (dst-start (* ,dst-start sb!vm:byte-bits))
340 (dst-end (* ,dst-end sb!vm:byte-bits)))
341 (let ((length (- dst-end dst-start)))
346 (system-area-copy src src-start dst dst-start length))
347 ((simple-unboxed-array (*))
348 (copy-from-system-area src src-start
349 dst (+ dst-start ,vector-data-bit-offset)
351 ((simple-unboxed-array (*))
354 (copy-to-system-area src (+ src-start ,vector-data-bit-offset)
357 ((simple-unboxed-array (*))
358 (bit-bash-copy src (+ src-start ,vector-data-bit-offset)
359 dst (+ dst-start ,vector-data-bit-offset)
362 ;;;; transforms for EQL of floating point values
364 (deftransform eql ((x y) (single-float single-float))
365 '(= (single-float-bits x) (single-float-bits y)))
367 (deftransform eql ((x y) (double-float double-float))
368 '(and (= (double-float-low-bits x) (double-float-low-bits y))
369 (= (double-float-high-bits x) (double-float-high-bits y))))