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 ;;; FIXME: Shouldn't we be testing for legality of
195 ;;; * START1, START2, END1, and END2 indices?
196 ;;; * size of copied string relative to destination string?
197 ;;; (Either there should be tests conditional on SAFETY>=SPEED, or
198 ;;; the transform should be conditional on SPEED>SAFETY.)
200 ;;; FIXME: Also, the transform should probably be dependent on
202 (deftransform replace ((string1 string2 &key (start1 0) (start2 0)
204 (simple-string simple-string &rest t))
206 (declare (optimize (safety 0)))
207 (bit-bash-copy string2
209 (+ (the index (* start2 sb!vm:byte-bits))
210 ,vector-data-bit-offset))
213 (+ (the index (* start1 sb!vm:byte-bits))
214 ,vector-data-bit-offset))
216 (* (min (the index (- (or end1 (length string1))
218 (the index (- (or end2 (length string2))
223 ;;;; bit vector hackery
225 ;;; SIMPLE-BIT-VECTOR bit-array operations are transformed to a word loop that
226 ;;; does 32 bits at a time.
228 ;;; FIXME: This is a lot of repeatedly macroexpanded code. It should be a
229 ;;; function call instead. And do it with DEF-FROB instead of DOLIST.
230 (dolist (x '((bit-and 32bit-logical-and)
231 (bit-ior 32bit-logical-or)
232 (bit-xor 32bit-logical-xor)
233 (bit-eqv 32bit-logical-eqv)
234 (bit-nand 32bit-logical-nand)
235 (bit-nor 32bit-logical-nor)
236 (bit-andc1 32bit-logical-andc1)
237 (bit-andc2 32bit-logical-andc2)
238 (bit-orc1 32bit-logical-orc1)
239 (bit-orc2 32bit-logical-orc2)))
240 (destructuring-bind (bitfun wordfun) x
242 ((bit-array-1 bit-array-2 result-bit-array)
243 '(simple-bit-vector simple-bit-vector simple-bit-vector) '*
244 :eval-name t :node node :policy (>= speed space))
246 ,@(unless (policy node (zerop safety))
247 '((unless (= (length bit-array-1) (length bit-array-2)
248 (length result-bit-array))
249 (error "Argument and/or result bit arrays are not the same length:~
251 bit-array-1 bit-array-2 result-bit-array))))
252 (do ((index sb!vm:vector-data-offset (1+ index))
253 (end (+ sb!vm:vector-data-offset
255 (+ (length bit-array-1)
258 ((= index end) result-bit-array)
259 (declare (optimize (speed 3) (safety 0))
260 (type index index end))
261 (setf (%raw-bits result-bit-array index)
262 (,wordfun (%raw-bits bit-array-1 index)
263 (%raw-bits bit-array-2 index))))))))
265 (deftransform bit-not
266 ((bit-array result-bit-array)
267 (simple-bit-vector simple-bit-vector) *
268 :node node :policy (>= speed space))
270 ,@(unless (policy node (zerop safety))
271 '((unless (= (length bit-array)
272 (length result-bit-array))
273 (error "Argument and result bit arrays are not the same length:~
275 bit-array result-bit-array))))
276 (do ((index sb!vm:vector-data-offset (1+ index))
277 (end (+ sb!vm:vector-data-offset
279 (+ (length bit-array)
280 (1- sb!vm:word-bits)))
282 ((= index end) result-bit-array)
283 (declare (optimize (speed 3) (safety 0))
284 (type index index end))
285 (setf (%raw-bits result-bit-array index)
286 (32bit-logical-not (%raw-bits bit-array index))))))
288 ;;;; primitive translator for BYTE-BLT
290 (def-primitive-translator byte-blt (src src-start dst dst-start dst-end)
292 (src-start (* ,src-start sb!vm:byte-bits))
294 (dst-start (* ,dst-start sb!vm:byte-bits))
295 (dst-end (* ,dst-end sb!vm:byte-bits)))
296 (let ((length (- dst-end dst-start)))
301 (system-area-copy src src-start dst dst-start length))
302 ((simple-unboxed-array (*))
303 (copy-from-system-area src src-start
304 dst (+ dst-start ,vector-data-bit-offset)
306 ((simple-unboxed-array (*))
309 (copy-to-system-area src (+ src-start ,vector-data-bit-offset)
312 ((simple-unboxed-array (*))
313 (bit-bash-copy src (+ src-start ,vector-data-bit-offset)
314 dst (+ dst-start ,vector-data-bit-offset)
317 ;;;; transforms for EQL of floating point values
319 (deftransform eql ((x y) (single-float single-float))
320 '(= (single-float-bits x) (single-float-bits y)))
322 (deftransform eql ((x y) (double-float double-float))
323 '(and (= (double-float-low-bits x) (double-float-low-bits y))
324 (= (double-float-high-bits x) (double-float-high-bits y))))