1 ;;;; This file contains stuff that implements the portable IR1
2 ;;;; semantics of type tests and coercion. The main thing we do is
3 ;;;; convert complex type operations into simpler code that can be
6 ;;;; This software is part of the SBCL system. See the README file for
9 ;;;; This software is derived from the CMU CL system, which was
10 ;;;; written at Carnegie Mellon University and released into the
11 ;;;; public domain. The software is in the public domain and is
12 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
13 ;;;; files for more information.
17 ;;;; type predicate translation
19 ;;;; We maintain a bidirectional association between type predicates
20 ;;;; and the tested type. The presence of a predicate in this
21 ;;;; association implies that it is desirable to implement tests of
22 ;;;; this type using the predicate. These are either predicates that
23 ;;;; the back end is likely to have special knowledge about, or
24 ;;;; predicates so complex that the only reasonable implentation is
25 ;;;; via function call.
27 ;;;; Some standard types (such as ATOM) are best tested by letting the
28 ;;;; TYPEP source transform do its thing with the expansion. These
29 ;;;; types (and corresponding predicates) are not maintained in this
30 ;;;; association. In this case, there need not be any predicate
31 ;;;; function unless it is required by the Common Lisp specification.
33 ;;;; The mapping between predicates and type structures is considered
34 ;;;; part of the backend; different backends can support different
35 ;;;; sets of predicates.
37 ;;; Establish an association between the type predicate NAME and the
38 ;;; corresponding TYPE. This causes the type predicate to be
39 ;;; recognized for purposes of optimization.
40 (defmacro define-type-predicate (name type)
41 `(%define-type-predicate ',name ',type))
42 (defun %define-type-predicate (name specifier)
43 (let ((type (specifier-type specifier)))
44 (setf (gethash name *backend-predicate-types*) type)
45 (setf *backend-type-predicates*
46 (cons (cons type name)
47 (remove name *backend-type-predicates*
49 (%deftransform name '(function (t) *) #'fold-type-predicate)
54 ;;; If we discover the type argument is constant during IR1
55 ;;; optimization, then give the source transform another chance. The
56 ;;; source transform can't pass, since we give it an explicit
57 ;;; constant. At worst, it will convert to %TYPEP, which will prevent
58 ;;; spurious attempts at transformation (and possible repeated
60 (deftransform typep ((object type &optional env) * * :node node)
61 (unless (constant-lvar-p type)
62 (give-up-ir1-transform "can't open-code test of non-constant type"))
63 (unless (and (constant-lvar-p env) (null (lvar-value env)))
64 (give-up-ir1-transform "environment argument present and not null"))
65 (multiple-value-bind (expansion fail-p)
66 (source-transform-typep 'object (lvar-value type))
71 ;;; If the lvar OBJECT definitely is or isn't of the specified
72 ;;; type, then return T or NIL as appropriate. Otherwise quietly
73 ;;; GIVE-UP-IR1-TRANSFORM.
74 (defun ir1-transform-type-predicate (object type node)
75 (declare (type lvar object) (type ctype type))
76 (let ((otype (lvar-type object)))
78 (cond ((typep type 'alien-type-type)
79 ;; We don't transform alien type tests until here, because
80 ;; once we do that the rest of the type system can no longer
81 ;; reason about them properly -- so we'd miss out on type
83 (delay-ir1-transform node :optimize)
84 (let ((alien-type (alien-type-type-alien-type type)))
85 ;; If it's a lisp-rep-type, the CTYPE should be one already.
86 (aver (not (compute-lisp-rep-type alien-type)))
87 `(sb!alien::alien-value-typep object ',alien-type)))
89 (give-up-ir1-transform)))))
90 (cond ((not (types-equal-or-intersect otype type))
92 ((csubtypep otype type)
94 ((eq type *empty-type*)
97 (let ((intersect (type-intersection2 type otype)))
100 (multiple-value-bind (constantp value)
101 (type-singleton-p intersect)
103 `(eql object ',value)
106 ;;; Flush %TYPEP tests whose result is known at compile time.
107 (deftransform %typep ((object type) * * :node node)
108 (unless (constant-lvar-p type)
109 (give-up-ir1-transform))
110 (ir1-transform-type-predicate
112 (ir1-transform-specifier-type (lvar-value type))
115 ;;; This is the IR1 transform for simple type predicates. It checks
116 ;;; whether the single argument is known to (not) be of the
117 ;;; appropriate type, expanding to T or NIL as appropriate.
118 (deftransform fold-type-predicate ((object) * * :node node :defun-only t)
119 (let ((ctype (gethash (leaf-source-name
122 (basic-combination-fun node))))
123 *backend-predicate-types*)))
125 (ir1-transform-type-predicate object ctype node)))
127 ;;; If FIND-CLASSOID is called on a constant class, locate the
128 ;;; CLASSOID-CELL at load time.
129 (deftransform find-classoid ((name) ((constant-arg symbol)) *)
130 (let* ((name (lvar-value name))
131 (cell (find-classoid-cell name :create t)))
132 `(or (classoid-cell-classoid ',cell)
133 (error "class not yet defined: ~S" name))))
135 ;;;; standard type predicates, i.e. those defined in package COMMON-LISP,
136 ;;;; plus at least one oddball (%INSTANCEP)
138 ;;;; Various other type predicates (e.g. low-level representation
139 ;;;; stuff like SIMPLE-ARRAY-SINGLE-FLOAT-P) are defined elsewhere.
141 ;;; FIXME: This function is only called once, at top level. Why not
142 ;;; just expand all its operations into toplevel code?
143 (defun !define-standard-type-predicates ()
144 (define-type-predicate arrayp array)
145 ; (The ATOM predicate is handled separately as (NOT CONS).)
146 (define-type-predicate bit-vector-p bit-vector)
147 (define-type-predicate characterp character)
148 (define-type-predicate compiled-function-p compiled-function)
149 (define-type-predicate complexp complex)
150 (define-type-predicate complex-rational-p (complex rational))
151 (define-type-predicate complex-float-p (complex float))
152 (define-type-predicate consp cons)
153 (define-type-predicate floatp float)
154 (define-type-predicate functionp function)
155 (define-type-predicate integerp integer)
156 (define-type-predicate keywordp keyword)
157 (define-type-predicate listp list)
158 (define-type-predicate null null)
159 (define-type-predicate numberp number)
160 (define-type-predicate rationalp rational)
161 (define-type-predicate realp real)
162 (define-type-predicate sequencep sequence)
163 (define-type-predicate extended-sequence-p extended-sequence)
164 (define-type-predicate simple-bit-vector-p simple-bit-vector)
165 (define-type-predicate simple-string-p simple-string)
166 (define-type-predicate simple-vector-p simple-vector)
167 (define-type-predicate stringp string)
168 (define-type-predicate %instancep instance)
169 (define-type-predicate funcallable-instance-p funcallable-instance)
170 (define-type-predicate symbolp symbol)
171 (define-type-predicate vectorp vector))
172 (!define-standard-type-predicates)
174 ;;;; transforms for type predicates not implemented primitively
176 ;;;; See also VM dependent transforms.
178 (define-source-transform atom (x)
181 (define-source-transform base-char-p (x)
182 `(typep ,x 'base-char))
184 ;;;; TYPEP source transform
186 ;;; Return a form that tests the variable N-OBJECT for being in the
187 ;;; binds specified by TYPE. BASE is the name of the base type, for
188 ;;; declaration. We make SAFETY locally 0 to inhibit any checking of
190 (defun transform-numeric-bound-test (n-object type base)
191 (declare (type numeric-type type))
192 (let ((low (numeric-type-low type))
193 (high (numeric-type-high type)))
195 (declare (optimize (safety 0)))
198 `((> (truly-the ,base ,n-object) ,(car low)))
199 `((>= (truly-the ,base ,n-object) ,low))))
202 `((< (truly-the ,base ,n-object) ,(car high)))
203 `((<= (truly-the ,base ,n-object) ,high))))))))
205 ;;; Do source transformation of a test of a known numeric type. We can
206 ;;; assume that the type doesn't have a corresponding predicate, since
207 ;;; those types have already been picked off. In particular, CLASS
208 ;;; must be specified, since it is unspecified only in NUMBER and
209 ;;; COMPLEX. Similarly, we assume that COMPLEXP is always specified.
211 ;;; For non-complex types, we just test that the number belongs to the
212 ;;; base type, and then test that it is in bounds. When CLASS is
213 ;;; INTEGER, we check to see whether the range is no bigger than
214 ;;; FIXNUM. If so, we check for FIXNUM instead of INTEGER. This allows
215 ;;; us to use fixnum comparison to test the bounds.
217 ;;; For complex types, we must test for complex, then do the above on
218 ;;; both the real and imaginary parts. When CLASS is float, we need
219 ;;; only check the type of the realpart, since the format of the
220 ;;; realpart and the imagpart must be the same.
221 (defun source-transform-numeric-typep (object type)
222 (let* ((class (numeric-type-class type))
224 (integer (containing-integer-type
225 (if (numeric-type-complexp type)
226 (modified-numeric-type type
230 (float (or (numeric-type-format type) 'float))
232 (once-only ((n-object object))
233 (ecase (numeric-type-complexp type)
235 `(and (typep ,n-object ',base)
236 ,(transform-numeric-bound-test n-object type base)))
238 `(and (complexp ,n-object)
239 ,(once-only ((n-real `(realpart (truly-the complex ,n-object)))
240 (n-imag `(imagpart (truly-the complex ,n-object))))
243 (and (typep ,n-real ',base)
244 ,@(when (eq class 'integer)
245 `((typep ,n-imag ',base)))
246 ,(transform-numeric-bound-test n-real type base)
247 ,(transform-numeric-bound-test n-imag type
250 ;;; Do the source transformation for a test of a hairy type. AND,
251 ;;; SATISFIES and NOT are converted into the obvious code. We convert
252 ;;; unknown types to %TYPEP, emitting an efficiency note if
254 (defun source-transform-hairy-typep (object type)
255 (declare (type hairy-type type))
256 (let ((spec (hairy-type-specifier type)))
257 (cond ((unknown-type-p type)
258 (when (policy *lexenv* (> speed inhibit-warnings))
259 (compiler-notify "can't open-code test of unknown type ~S"
260 (type-specifier type)))
261 `(%typep ,object ',spec))
265 `(if (funcall (global-function ,(second spec)) ,object) t nil))
267 (once-only ((n-obj object))
268 `(,(first spec) ,@(mapcar (lambda (x)
272 (defun source-transform-negation-typep (object type)
273 (declare (type negation-type type))
274 (let ((spec (type-specifier (negation-type-type type))))
275 `(not (typep ,object ',spec))))
277 ;;; Do source transformation for TYPEP of a known union type. If a
278 ;;; union type contains LIST, then we pull that out and make it into a
279 ;;; single LISTP call. Note that if SYMBOL is in the union, then LIST
280 ;;; will be a subtype even without there being any (member NIL). We
281 ;;; currently just drop through to the general code in this case,
282 ;;; rather than trying to optimize it (but FIXME CSR 2004-04-05: it
283 ;;; wouldn't be hard to optimize it after all).
284 (defun source-transform-union-typep (object type)
285 (let* ((types (union-type-types type))
286 (type-cons (specifier-type 'cons))
287 (mtype (find-if #'member-type-p types))
288 (members (when mtype (member-type-members mtype))))
291 (memq type-cons types))
292 (once-only ((n-obj object))
295 '(or ,@(mapcar #'type-specifier
297 (remove mtype types)))
298 (member ,@(remove nil members))))))
299 (once-only ((n-obj object))
300 `(or ,@(mapcar (lambda (x)
301 `(typep ,n-obj ',(type-specifier x)))
304 ;;; Do source transformation for TYPEP of a known intersection type.
305 (defun source-transform-intersection-typep (object type)
306 (once-only ((n-obj object))
307 `(and ,@(mapcar (lambda (x)
308 `(typep ,n-obj ',(type-specifier x)))
309 (intersection-type-types type)))))
311 ;;; If necessary recurse to check the cons type.
312 (defun source-transform-cons-typep (object type)
313 (let* ((car-type (cons-type-car-type type))
314 (cdr-type (cons-type-cdr-type type)))
315 (let ((car-test-p (not (type= car-type *universal-type*)))
316 (cdr-test-p (not (type= cdr-type *universal-type*))))
317 (if (and (not car-test-p) (not cdr-test-p))
319 (once-only ((n-obj object))
322 `((typep (car ,n-obj)
323 ',(type-specifier car-type))))
325 `((typep (cdr ,n-obj)
326 ',(type-specifier cdr-type))))))))))
328 (defun source-transform-character-set-typep (object type)
329 (let ((pairs (character-set-type-pairs type)))
330 (if (and (= (length pairs) 1)
332 (= (cdar pairs) (1- sb!xc:char-code-limit)))
333 `(characterp ,object)
334 (once-only ((n-obj object))
335 (let ((n-code (gensym "CODE")))
336 `(and (characterp ,n-obj)
337 (let ((,n-code (sb!xc:char-code ,n-obj)))
339 ,@(loop for pair in pairs
341 `(<= ,(car pair) ,n-code ,(cdr pair)))))))))))
343 ;;; Return the predicate and type from the most specific entry in
344 ;;; *TYPE-PREDICATES* that is a supertype of TYPE.
345 (defun find-supertype-predicate (type)
346 (declare (type ctype type))
349 (dolist (x *backend-type-predicates*)
350 (let ((stype (car x)))
351 (when (and (csubtypep type stype)
353 (csubtypep stype res-type)))
354 (setq res-type stype)
355 (setq res (cdr x)))))
356 (values res res-type)))
358 ;;; Return forms to test that OBJ has the rank and dimensions
359 ;;; specified by TYPE, where STYPE is the type we have checked against
360 ;;; (which is the same but for dimensions and element type).
362 ;;; Secondary return value is true if passing the generated tests implies that
363 ;;; the array has a header.
364 (defun test-array-dimensions (obj type stype)
365 (declare (type array-type type stype))
366 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
367 (dims (array-type-dimensions type)))
368 (unless (or (eq dims '*)
369 (equal dims (array-type-dimensions stype)))
371 (values `((array-header-p ,obj)
372 ,@(when (eq (array-type-dimensions stype) '*)
373 `((= (%array-rank ,obj) ,(length dims))))
374 ,@(loop for d in dims
377 collect `(= (%array-dimension ,obj ,i) ,d)))
380 (values `((array-header-p ,obj)
381 (= (%array-rank ,obj) 0))
383 ((not (array-type-complexp type))
384 (if (csubtypep stype (specifier-type 'vector))
385 (values (unless (eq '* (car dims))
386 `((= (vector-length ,obj) ,@dims)))
388 (values (if (eq '* (car dims))
389 `((not (array-header-p ,obj)))
390 `((not (array-header-p ,obj))
391 (= (vector-length ,obj) ,@dims)))
394 (values (unless (eq '* (car dims))
395 `((if (array-header-p ,obj)
396 (= (%array-dimension ,obj 0) ,@dims)
397 (= (vector-length ,obj) ,@dims))))
400 ;;; Return forms to test that OBJ has the element-type specified by type
401 ;;; specified by TYPE, where STYPE is the type we have checked against (which
402 ;;; is the same but for dimensions and element type). If HEADERP is true, OBJ
403 ;;; is guaranteed to be an array-header.
404 (defun test-array-element-type (obj type stype headerp)
405 (declare (type array-type type stype))
406 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
407 (eltype (array-type-specialized-element-type type)))
408 (unless (or (type= eltype (array-type-specialized-element-type stype))
409 (eq eltype *wild-type*))
410 (let ((typecode (sb!vm:saetp-typecode (find-saetp-by-ctype eltype))))
411 (with-unique-names (data)
412 (if (and headerp (not (array-type-complexp stype)))
413 ;; If we know OBJ is an array header, and that the array is
414 ;; simple, we also know there is exactly one indirection to
416 `((eq (%other-pointer-widetag (%array-data-vector ,obj)) ,typecode))
417 `((do ((,data ,(if headerp `(%array-data-vector ,obj) obj)
418 (%array-data-vector ,data)))
419 ((not (array-header-p ,data))
420 (eq (%other-pointer-widetag ,data) ,typecode))))))))))
422 ;;; If we can find a type predicate that tests for the type without
423 ;;; dimensions, then use that predicate and test for dimensions.
424 ;;; Otherwise, just do %TYPEP.
425 (defun source-transform-array-typep (obj type)
426 (multiple-value-bind (pred stype) (find-supertype-predicate type)
427 (if (and (array-type-p stype)
428 ;; (If the element type hasn't been defined yet, it's
429 ;; not safe to assume here that it will eventually
430 ;; have (UPGRADED-ARRAY-ELEMENT-TYPE type)=T, so punt.)
431 (not (unknown-type-p (array-type-element-type type)))
432 (or (eq (array-type-complexp stype) (array-type-complexp type))
433 (and (eql (array-type-complexp stype) :maybe)
434 (eql (array-type-complexp type) t))))
435 (once-only ((n-obj obj))
436 (multiple-value-bind (tests headerp)
437 (test-array-dimensions n-obj type stype)
439 ,@(when (and (eql (array-type-complexp stype) :maybe)
440 (eql (array-type-complexp type) t))
441 ;; KLUDGE: this is a bit lame; if we get here,
442 ;; we already know that N-OBJ is an array, but
443 ;; (NOT SIMPLE-ARRAY) doesn't know that. On the
444 ;; other hand, this should get compiled down to
445 ;; two widetag tests, so it's only a bit lame.
446 `((typep ,n-obj '(not simple-array))))
448 ,@(test-array-element-type n-obj type stype headerp))))
449 `(%typep ,obj ',(type-specifier type)))))
451 ;;; Transform a type test against some instance type. The type test is
452 ;;; flushed if the result is known at compile time. If not properly
453 ;;; named, error. If sealed and has no subclasses, just test for
454 ;;; layout-EQ. If a structure then test for layout-EQ and then a
455 ;;; general test based on layout-inherits. If safety is important,
456 ;;; then we also check whether the layout for the object is invalid
457 ;;; and signal an error if so. Otherwise, look up the indirect
458 ;;; class-cell and call CLASS-CELL-TYPEP at runtime.
459 (deftransform %instance-typep ((object spec) (* *) * :node node)
460 (aver (constant-lvar-p spec))
461 (let* ((spec (lvar-value spec))
462 (class (specifier-type spec))
463 (name (classoid-name class))
464 (otype (lvar-type object))
465 (layout (let ((res (info :type :compiler-layout name)))
466 (if (and res (not (layout-invalid res)))
470 ;; Flush tests whose result is known at compile time.
471 ((not (types-equal-or-intersect otype class))
473 ((csubtypep otype class)
475 ;; If not properly named, error.
476 ((not (and name (eq (find-classoid name) class)))
477 (compiler-error "can't compile TYPEP of anonymous or undefined ~
481 ;; Delay the type transform to give type propagation a chance.
482 (delay-ir1-transform node :constraint)
484 ;; Otherwise transform the type test.
485 (multiple-value-bind (pred get-layout)
487 ((csubtypep class (specifier-type 'funcallable-instance))
488 (values 'funcallable-instance-p '%funcallable-instance-layout))
489 ((csubtypep class (specifier-type 'instance))
490 (values '%instancep '%instance-layout))
492 (values '(lambda (x) (declare (ignore x)) t) 'layout-of)))
494 ((and (eq (classoid-state class) :sealed) layout
495 (not (classoid-subclasses class)))
496 ;; Sealed and has no subclasses.
497 (let ((n-layout (gensym)))
499 (let ((,n-layout (,get-layout object)))
500 ,@(when (policy *lexenv* (>= safety speed))
501 `((when (layout-invalid ,n-layout)
502 (%layout-invalid-error object ',layout))))
503 (eq ,n-layout ',layout)))))
504 ((and (typep class 'structure-classoid) layout)
505 ;; structure type tests; hierarchical layout depths
506 (let ((depthoid (layout-depthoid layout))
509 (let ((,n-layout (,get-layout object)))
510 ;; we used to check for invalid layouts here,
511 ;; but in fact that's both unnecessary and
512 ;; wrong; it's unnecessary because structure
513 ;; classes can't be redefined, and it's wrong
514 ;; because it is quite legitimate to pass an
515 ;; object with an invalid layout to a structure
517 (if (eq ,n-layout ',layout)
519 (and (> (layout-depthoid ,n-layout)
521 (locally (declare (optimize (safety 0)))
522 ;; Use DATA-VECTOR-REF directly,
523 ;; since that's what SVREF in a
524 ;; SAFETY 0 lexenv will eventually be
525 ;; transformed to. This can give a
526 ;; large compilation speedup, since
527 ;; %INSTANCE-TYPEPs are frequently
528 ;; created during GENERATE-TYPE-CHECKS,
529 ;; and the normal aref transformation path
531 (eq (data-vector-ref (layout-inherits ,n-layout)
534 ((and layout (>= (layout-depthoid layout) 0))
535 ;; hierarchical layout depths for other things (e.g.
536 ;; CONDITION, STREAM)
537 (let ((depthoid (layout-depthoid layout))
539 (n-inherits (gensym)))
541 (let ((,n-layout (,get-layout object)))
542 (when (layout-invalid ,n-layout)
543 (setq ,n-layout (update-object-layout-or-invalid
545 (if (eq ,n-layout ',layout)
547 (let ((,n-inherits (layout-inherits ,n-layout)))
548 (declare (optimize (safety 0)))
549 (and (> (length ,n-inherits) ,depthoid)
551 (eq (data-vector-ref ,n-inherits ,depthoid)
554 (/noshow "default case -- ,PRED and CLASS-CELL-TYPEP")
556 (classoid-cell-typep (,get-layout object)
557 ',(find-classoid-cell name :create t)
560 ;;; If the specifier argument is a quoted constant, then we consider
561 ;;; converting into a simple predicate or other stuff. If the type is
562 ;;; constant, but we can't transform the call, then we convert to
563 ;;; %TYPEP. We only pass when the type is non-constant. This allows us
564 ;;; to recognize between calls that might later be transformed
565 ;;; successfully when a constant type is discovered. We don't give an
566 ;;; efficiency note when we pass, since the IR1 transform will give
567 ;;; one if necessary and appropriate.
569 ;;; If the type is TYPE= to a type that has a predicate, then expand
570 ;;; to that predicate. Otherwise, we dispatch off of the type's type.
571 ;;; These transformations can increase space, but it is hard to tell
572 ;;; when, so we ignore policy and always do them.
573 (defun source-transform-typep (object type)
574 (let ((ctype (careful-specifier-type type)))
575 (or (when (not ctype)
576 (compiler-warn "illegal type specifier for TYPEP: ~S" type)
577 (return-from source-transform-typep (values nil t)))
578 (multiple-value-bind (constantp value) (type-singleton-p ctype)
580 `(eql ,object ',value)))
581 (let ((pred (cdr (assoc ctype *backend-type-predicates*
583 (when pred `(,pred ,object)))
586 (source-transform-hairy-typep object ctype))
588 (source-transform-negation-typep object ctype))
590 (source-transform-union-typep object ctype))
592 (source-transform-intersection-typep object ctype))
594 `(if (member ,object ',(member-type-members ctype)) t))
596 (compiler-warn "illegal type specifier for TYPEP: ~S" type)
597 (return-from source-transform-typep (values nil t)))
601 (source-transform-numeric-typep object ctype))
603 `(%instance-typep ,object ',type))
605 (source-transform-array-typep object ctype))
607 (source-transform-cons-typep object ctype))
609 (source-transform-character-set-typep object ctype))
611 `(%typep ,object ',type))))
613 (define-source-transform typep (object spec &optional env)
614 ;; KLUDGE: It looks bad to only do this on explicitly quoted forms,
615 ;; since that would overlook other kinds of constants. But it turns
616 ;; out that the DEFTRANSFORM for TYPEP detects any constant
617 ;; lvar, transforms it into a quoted form, and gives this
618 ;; source transform another chance, so it all works out OK, in a
619 ;; weird roundabout way. -- WHN 2001-03-18
622 (eq (car spec) 'quote)
623 (or (not *allow-instrumenting*)
624 (policy *lexenv* (= store-coverage-data 0))))
625 (source-transform-typep object (cadr spec))
630 ;;; Constant-folding.
633 (defoptimizer (coerce optimizer) ((x type) node)
634 (when (and (constant-lvar-p x) (constant-lvar-p type))
635 (let ((value (lvar-value x)))
636 (when (or (numberp value) (characterp value))
637 (constant-fold-call node)
640 ;;; Drops dimension information from vector types.
641 (defun simplify-vector-type (type)
642 (aver (csubtypep type (specifier-type '(array * (*)))))
644 (if (csubtypep type (specifier-type 'simple-array))
649 (or (eq 'simple-array array-type)
651 (type-intersection type (specifier-type 'simple-array)))))))
653 #+sb-xc-host '(t bit character)
654 #-sb-xc-host sb!kernel::*specialized-array-element-types*
655 #+sb-xc-host (values nil nil nil)
656 #-sb-xc-host (values `(,array-type * (*)) t complexp))
658 (let ((simplified (specifier-type `(,array-type ,etype (*)))))
659 (when (csubtypep type simplified)
660 (return (values (type-specifier simplified)
664 (deftransform coerce ((x type) (* *) * :node node)
665 (unless (constant-lvar-p type)
666 (give-up-ir1-transform))
667 (let* ((tval (lvar-value type))
668 (tspec (ir1-transform-specifier-type tval)))
669 (if (csubtypep (lvar-type x) tspec)
671 ;; Note: The THE forms we use to wrap the results make sure that
672 ;; specifiers like (SINGLE-FLOAT 0.0 1.0) can raise a TYPE-ERROR.
674 ((csubtypep tspec (specifier-type 'double-float))
675 `(the ,tval (%double-float x)))
676 ;; FIXME: #!+long-float (t ,(error "LONG-FLOAT case needed"))
677 ((csubtypep tspec (specifier-type 'float))
678 `(the ,tval (%single-float x)))
679 ;; Special case STRING and SIMPLE-STRING as they are union types
681 ((member tval '(string simple-string))
685 (replace (make-array (length x) :element-type 'character) x))))
686 ;; Special case VECTOR
691 (replace (make-array (length x)) x))))
692 ;; Handle specialized element types for 1D arrays.
693 ((csubtypep tspec (specifier-type '(array * (*))))
694 ;; Can we avoid checking for dimension issues like (COERCE FOO
695 ;; '(SIMPLE-VECTOR 5)) returning a vector of length 6?
697 ;; CLHS actually allows this for all code with SAFETY < 3,
698 ;; but we're a conservative bunch.
699 (if (or (policy node (zerop safety)) ; no need in unsafe code
700 (and (array-type-p tspec) ; no need when no dimensions
701 (equal (array-type-dimensions tspec) '(*))))
703 (multiple-value-bind (vtype etype complexp) (simplify-vector-type tspec)
705 (give-up-ir1-transform))
707 (if (typep x ',vtype)
710 (make-array (length x) :element-type ',etype
712 (list :fill-pointer t
715 ;; No, duh. Dimension checking required.
716 (give-up-ir1-transform
717 "~@<~S specifies dimensions other than (*) in safe code.~:@>"
720 (give-up-ir1-transform
721 "~@<open coding coercion to ~S not implemented.~:@>"