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 SEQUENCE) are best tested by letting
28 ;;;; the 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))
61 (unless (constant-continuation-p type)
62 (give-up-ir1-transform "can't open-code test of non-constant type"))
63 `(typep object ',(continuation-value type)))
65 ;;; If the continuation OBJECT definitely is or isn't of the specified
66 ;;; type, then return T or NIL as appropriate. Otherwise quietly
67 ;;; GIVE-UP-IR1-TRANSFORM.
68 (defun ir1-transform-type-predicate (object type)
69 (declare (type continuation object) (type ctype type))
70 (let ((otype (continuation-type object)))
71 (cond ((not (types-equal-or-intersect otype type))
73 ((csubtypep otype type)
75 ((eq type *empty-type*)
78 (give-up-ir1-transform)))))
80 ;;; Flush %TYPEP tests whose result is known at compile time.
81 (deftransform %typep ((object type))
82 (unless (constant-continuation-p type)
83 (give-up-ir1-transform))
84 (ir1-transform-type-predicate
86 (ir1-transform-specifier-type (continuation-value type))))
88 ;;; This is the IR1 transform for simple type predicates. It checks
89 ;;; whether the single argument is known to (not) be of the
90 ;;; appropriate type, expanding to T or NIL as appropriate.
91 (deftransform fold-type-predicate ((object) * * :node node :defun-only t)
92 (let ((ctype (gethash (leaf-source-name
95 (basic-combination-fun node))))
96 *backend-predicate-types*)))
98 (ir1-transform-type-predicate object ctype)))
100 ;;; If FIND-CLASS is called on a constant class, locate the CLASS-CELL
102 (deftransform find-classoid ((name) ((constant-arg symbol)) *)
103 (let* ((name (continuation-value name))
104 (cell (find-classoid-cell name)))
105 `(or (classoid-cell-classoid ',cell)
106 (error "class not yet defined: ~S" name))))
108 ;;;; standard type predicates, i.e. those defined in package COMMON-LISP,
109 ;;;; plus at least one oddball (%INSTANCEP)
111 ;;;; Various other type predicates (e.g. low-level representation
112 ;;;; stuff like SIMPLE-ARRAY-SINGLE-FLOAT-P) are defined elsewhere.
114 ;;; FIXME: This function is only called once, at top level. Why not
115 ;;; just expand all its operations into toplevel code?
116 (defun !define-standard-type-predicates ()
117 (define-type-predicate arrayp array)
118 ; (The ATOM predicate is handled separately as (NOT CONS).)
119 (define-type-predicate bit-vector-p bit-vector)
120 (define-type-predicate characterp character)
121 (define-type-predicate compiled-function-p compiled-function)
122 (define-type-predicate complexp complex)
123 (define-type-predicate complex-rational-p (complex rational))
124 (define-type-predicate complex-float-p (complex float))
125 (define-type-predicate consp cons)
126 (define-type-predicate floatp float)
127 (define-type-predicate functionp function)
128 (define-type-predicate integerp integer)
129 (define-type-predicate keywordp keyword)
130 (define-type-predicate listp list)
131 (define-type-predicate null null)
132 (define-type-predicate numberp number)
133 (define-type-predicate rationalp rational)
134 (define-type-predicate realp real)
135 (define-type-predicate simple-bit-vector-p simple-bit-vector)
136 (define-type-predicate simple-string-p simple-string)
137 (define-type-predicate simple-vector-p simple-vector)
138 (define-type-predicate stringp string)
139 (define-type-predicate %instancep instance)
140 (define-type-predicate funcallable-instance-p funcallable-instance)
141 (define-type-predicate symbolp symbol)
142 (define-type-predicate vectorp vector))
143 (!define-standard-type-predicates)
145 ;;;; transforms for type predicates not implemented primitively
147 ;;;; See also VM dependent transforms.
149 (define-source-transform atom (x)
152 ;;;; TYPEP source transform
154 ;;; Return a form that tests the variable N-OBJECT for being in the
155 ;;; binds specified by TYPE. BASE is the name of the base type, for
156 ;;; declaration. We make SAFETY locally 0 to inhibit any checking of
158 #!-negative-zero-is-not-zero
159 (defun transform-numeric-bound-test (n-object type base)
160 (declare (type numeric-type type))
161 (let ((low (numeric-type-low type))
162 (high (numeric-type-high type)))
164 (declare (optimize (safety 0)))
167 `((> (the ,base ,n-object) ,(car low)))
168 `((>= (the ,base ,n-object) ,low))))
171 `((< (the ,base ,n-object) ,(car high)))
172 `((<= (the ,base ,n-object) ,high))))))))
174 #!+negative-zero-is-not-zero
175 (defun transform-numeric-bound-test (n-object type base)
176 (declare (type numeric-type type))
177 (let ((low (numeric-type-low type))
178 (high (numeric-type-high type))
179 (float-type-p (csubtypep type (specifier-type 'float)))
183 (declare (optimize (safety 0)))
186 `((let ((,x (the ,base ,n-object))
188 ,(if (not float-type-p)
190 `(if (and (zerop ,x) (zerop ,y))
191 (> (float-sign ,x) (float-sign ,y))
193 `((let ((,x (the ,base ,n-object))
195 ,(if (not float-type-p)
197 `(if (and (zerop ,x) (zerop ,y))
198 (>= (float-sign ,x) (float-sign ,y))
202 `((let ((,x (the ,base ,n-object))
204 ,(if (not float-type-p)
206 `(if (and (zerop ,x) (zerop ,y))
207 (< (float-sign ,x) (float-sign ,y))
209 `((let ((,x (the ,base ,n-object))
211 ,(if (not float-type-p)
213 `(if (and (zerop ,x) (zerop ,y))
214 (<= (float-sign ,x) (float-sign ,y))
217 ;;; Do source transformation of a test of a known numeric type. We can
218 ;;; assume that the type doesn't have a corresponding predicate, since
219 ;;; those types have already been picked off. In particular, CLASS
220 ;;; must be specified, since it is unspecified only in NUMBER and
221 ;;; COMPLEX. Similarly, we assume that COMPLEXP is always specified.
223 ;;; For non-complex types, we just test that the number belongs to the
224 ;;; base type, and then test that it is in bounds. When CLASS is
225 ;;; INTEGER, we check to see whether the range is no bigger than
226 ;;; FIXNUM. If so, we check for FIXNUM instead of INTEGER. This allows
227 ;;; us to use fixnum comparison to test the bounds.
229 ;;; For complex types, we must test for complex, then do the above on
230 ;;; both the real and imaginary parts. When CLASS is float, we need
231 ;;; only check the type of the realpart, since the format of the
232 ;;; realpart and the imagpart must be the same.
233 (defun source-transform-numeric-typep (object type)
234 (let* ((class (numeric-type-class type))
236 (integer (containing-integer-type type))
238 (float (or (numeric-type-format type) 'float))
240 (once-only ((n-object object))
241 (ecase (numeric-type-complexp type)
243 `(and (typep ,n-object ',base)
244 ,(transform-numeric-bound-test n-object type base)))
246 `(and (complexp ,n-object)
247 ,(once-only ((n-real `(realpart (the complex ,n-object)))
248 (n-imag `(imagpart (the complex ,n-object))))
251 (and (typep ,n-real ',base)
252 ,@(when (eq class 'integer)
253 `((typep ,n-imag ',base)))
254 ,(transform-numeric-bound-test n-real type base)
255 ,(transform-numeric-bound-test n-imag type
258 ;;; Do the source transformation for a test of a hairy type. AND,
259 ;;; SATISFIES and NOT are converted into the obvious code. We convert
260 ;;; unknown types to %TYPEP, emitting an efficiency note if
262 (defun source-transform-hairy-typep (object type)
263 (declare (type hairy-type type))
264 (let ((spec (hairy-type-specifier type)))
265 (cond ((unknown-type-p type)
266 (when (policy *lexenv* (> speed inhibit-warnings))
267 (compiler-note "can't open-code test of unknown type ~S"
268 (type-specifier type)))
269 `(%typep ,object ',spec))
272 (satisfies `(if (funcall #',(second spec) ,object) t nil))
274 (once-only ((n-obj object))
275 `(,(first spec) ,@(mapcar (lambda (x)
279 (defun source-transform-negation-typep (object type)
280 (declare (type negation-type type))
281 (let ((spec (type-specifier (negation-type-type type))))
282 `(not (typep ,object ',spec))))
284 ;;; Do source transformation for TYPEP of a known union type. If a
285 ;;; union type contains LIST, then we pull that out and make it into a
286 ;;; single LISTP call. Note that if SYMBOL is in the union, then LIST
287 ;;; will be a subtype even without there being any (member NIL). We
288 ;;; just drop through to the general code in this case, rather than
289 ;;; trying to optimize it.
290 (defun source-transform-union-typep (object type)
291 (let* ((types (union-type-types type))
292 (ltype (specifier-type 'list))
293 (mtype (find-if #'member-type-p types)))
294 (if (and mtype (csubtypep ltype type))
295 (let ((members (member-type-members mtype)))
296 (once-only ((n-obj object))
299 '(or ,@(mapcar #'type-specifier
300 (remove (specifier-type 'cons)
301 (remove mtype types)))
302 (member ,@(remove nil members)))))))
303 (once-only ((n-obj object))
304 `(or ,@(mapcar (lambda (x)
305 `(typep ,n-obj ',(type-specifier x)))
308 ;;; Do source transformation for TYPEP of a known intersection type.
309 (defun source-transform-intersection-typep (object type)
310 (once-only ((n-obj object))
311 `(and ,@(mapcar (lambda (x)
312 `(typep ,n-obj ',(type-specifier x)))
313 (intersection-type-types type)))))
315 ;;; If necessary recurse to check the cons type.
316 (defun source-transform-cons-typep (object type)
317 (let* ((car-type (cons-type-car-type type))
318 (cdr-type (cons-type-cdr-type type)))
319 (let ((car-test-p (not (or (type= car-type *wild-type*)
320 (type= car-type (specifier-type t)))))
321 (cdr-test-p (not (or (type= cdr-type *wild-type*)
322 (type= cdr-type (specifier-type t))))))
323 (if (and (not car-test-p) (not cdr-test-p))
325 (once-only ((n-obj object))
328 `((typep (car ,n-obj)
329 ',(type-specifier car-type))))
331 `((typep (cdr ,n-obj)
332 ',(type-specifier cdr-type))))))))))
334 ;;; Return the predicate and type from the most specific entry in
335 ;;; *TYPE-PREDICATES* that is a supertype of TYPE.
336 (defun find-supertype-predicate (type)
337 (declare (type ctype type))
340 (dolist (x *backend-type-predicates*)
341 (let ((stype (car x)))
342 (when (and (csubtypep type stype)
344 (csubtypep stype res-type)))
345 (setq res-type stype)
346 (setq res (cdr x)))))
347 (values res res-type)))
349 ;;; Return forms to test that OBJ has the rank and dimensions
350 ;;; specified by TYPE, where STYPE is the type we have checked against
351 ;;; (which is the same but for dimensions.)
352 (defun test-array-dimensions (obj type stype)
353 (declare (type array-type type stype))
354 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
355 (dims (array-type-dimensions type)))
358 (when (eq (array-type-dimensions stype) '*)
359 (res `(= (array-rank ,obj) ,(length dims))))
361 (dim dims (cdr dim)))
363 (let ((dim (car dim)))
365 (res `(= (array-dimension ,obj ,i) ,dim)))))
368 ;;; If we can find a type predicate that tests for the type without
369 ;;; dimensions, then use that predicate and test for dimensions.
370 ;;; Otherwise, just do %TYPEP.
371 (defun source-transform-array-typep (obj type)
372 (multiple-value-bind (pred stype) (find-supertype-predicate type)
373 (if (and (array-type-p stype)
374 ;; (If the element type hasn't been defined yet, it's
375 ;; not safe to assume here that it will eventually
376 ;; have (UPGRADED-ARRAY-ELEMENT-TYPE type)=T, so punt.)
377 (not (unknown-type-p (array-type-element-type type)))
378 (type= (array-type-specialized-element-type stype)
379 (array-type-specialized-element-type type))
380 (eq (array-type-complexp stype) (array-type-complexp type)))
381 (once-only ((n-obj obj))
383 ,@(test-array-dimensions n-obj type stype)))
384 `(%typep ,obj ',(type-specifier type)))))
386 ;;; Transform a type test against some instance type. The type test is
387 ;;; flushed if the result is known at compile time. If not properly
388 ;;; named, error. If sealed and has no subclasses, just test for
389 ;;; layout-EQ. If a structure then test for layout-EQ and then a
390 ;;; general test based on layout-inherits. If safety is important,
391 ;;; then we also check whether the layout for the object is invalid
392 ;;; and signal an error if so. Otherwise, look up the indirect
393 ;;; class-cell and call CLASS-CELL-TYPEP at runtime.
394 (deftransform %instance-typep ((object spec) (* *) * :node node)
395 (aver (constant-continuation-p spec))
396 (let* ((spec (continuation-value spec))
397 (class (specifier-type spec))
398 (name (classoid-name class))
399 (otype (continuation-type object))
400 (layout (let ((res (info :type :compiler-layout name)))
401 (if (and res (not (layout-invalid res)))
405 ;; Flush tests whose result is known at compile time.
406 ((not (types-equal-or-intersect otype class))
408 ((csubtypep otype class)
410 ;; If not properly named, error.
411 ((not (and name (eq (find-classoid name) class)))
412 (compiler-error "can't compile TYPEP of anonymous or undefined ~
416 ;; Delay the type transform to give type propagation a chance.
417 (delay-ir1-transform node :constraint)
419 ;; Otherwise transform the type test.
420 (multiple-value-bind (pred get-layout)
422 ((csubtypep class (specifier-type 'funcallable-instance))
423 (values 'funcallable-instance-p '%funcallable-instance-layout))
424 ((csubtypep class (specifier-type 'instance))
425 (values '%instancep '%instance-layout))
427 (values '(lambda (x) (declare (ignore x)) t) 'layout-of)))
429 ((and (eq (classoid-state class) :sealed) layout
430 (not (classoid-subclasses class)))
431 ;; Sealed and has no subclasses.
432 (let ((n-layout (gensym)))
434 (let ((,n-layout (,get-layout object)))
435 ,@(when (policy *lexenv* (>= safety speed))
436 `((when (layout-invalid ,n-layout)
437 (%layout-invalid-error object ',layout))))
438 (eq ,n-layout ',layout)))))
439 ((and (typep class 'basic-structure-classoid) layout)
440 ;; structure type tests; hierarchical layout depths
441 (let ((depthoid (layout-depthoid layout))
444 (let ((,n-layout (,get-layout object)))
445 ,@(when (policy *lexenv* (>= safety speed))
446 `((when (layout-invalid ,n-layout)
447 (%layout-invalid-error object ',layout))))
448 (if (eq ,n-layout ',layout)
450 (and (> (layout-depthoid ,n-layout)
452 (locally (declare (optimize (safety 0)))
453 (eq (svref (layout-inherits ,n-layout)
456 ((and layout (>= (layout-depthoid layout) 0))
457 ;; hierarchical layout depths for other things (e.g.
459 (let ((depthoid (layout-depthoid layout))
461 (n-inherits (gensym)))
463 (let ((,n-layout (,get-layout object)))
464 ,@(when (policy *lexenv* (>= safety speed))
465 `((when (layout-invalid ,n-layout)
466 (%layout-invalid-error object ',layout))))
467 (if (eq ,n-layout ',layout)
469 (let ((,n-inherits (layout-inherits ,n-layout)))
470 (declare (optimize (safety 0)))
471 (and (> (length ,n-inherits) ,depthoid)
472 (eq (svref ,n-inherits ,depthoid)
475 (/noshow "default case -- ,PRED and CLASS-CELL-TYPEP")
477 (classoid-cell-typep (,get-layout object)
478 ',(find-classoid-cell name)
481 ;;; If the specifier argument is a quoted constant, then we consider
482 ;;; converting into a simple predicate or other stuff. If the type is
483 ;;; constant, but we can't transform the call, then we convert to
484 ;;; %TYPEP. We only pass when the type is non-constant. This allows us
485 ;;; to recognize between calls that might later be transformed
486 ;;; successfully when a constant type is discovered. We don't give an
487 ;;; efficiency note when we pass, since the IR1 transform will give
488 ;;; one if necessary and appropriate.
490 ;;; If the type is TYPE= to a type that has a predicate, then expand
491 ;;; to that predicate. Otherwise, we dispatch off of the type's type.
492 ;;; These transformations can increase space, but it is hard to tell
493 ;;; when, so we ignore policy and always do them.
494 (define-source-transform typep (object spec)
495 ;; KLUDGE: It looks bad to only do this on explicitly quoted forms,
496 ;; since that would overlook other kinds of constants. But it turns
497 ;; out that the DEFTRANSFORM for TYPEP detects any constant
498 ;; continuation, transforms it into a quoted form, and gives this
499 ;; source transform another chance, so it all works out OK, in a
500 ;; weird roundabout way. -- WHN 2001-03-18
501 (if (and (consp spec) (eq (car spec) 'quote))
502 (let ((type (careful-specifier-type (cadr spec))))
504 (compiler-warn "illegal type specifier for TYPEP: ~S"
506 `(%typep ,object ,spec))
507 (let ((pred (cdr (assoc type *backend-type-predicates*
509 (when pred `(,pred ,object)))
512 (source-transform-hairy-typep object type))
514 (source-transform-negation-typep object type))
516 (source-transform-union-typep object type))
518 (source-transform-intersection-typep object type))
520 `(member ,object ',(member-type-members type)))
522 (compiler-warn "illegal type specifier for TYPEP: ~S"
524 `(%typep ,object ,spec))
528 (source-transform-numeric-typep object type))
530 `(%instance-typep ,object ,spec))
532 (source-transform-array-typep object type))
534 (source-transform-cons-typep object type))
536 `(%typep ,object ,spec)))
541 (deftransform coerce ((x type) (* *) * :node node)
542 (unless (constant-continuation-p type)
543 (give-up-ir1-transform))
544 (let ((tspec (ir1-transform-specifier-type (continuation-value type))))
545 (if (csubtypep (continuation-type x) tspec)
547 ;; Note: The THE here makes sure that specifiers like
548 ;; (SINGLE-FLOAT 0.0 1.0) can raise a TYPE-ERROR.
549 `(the ,(continuation-value type)
551 ((csubtypep tspec (specifier-type 'double-float))
553 ;; FIXME: #!+long-float (t ,(error "LONG-FLOAT case needed"))
554 ((csubtypep tspec (specifier-type 'float))
556 ((and (csubtypep tspec (specifier-type 'simple-vector))
557 ;; Can we avoid checking for dimension issues like
558 ;; (COERCE FOO '(SIMPLE-VECTOR 5)) returning a
559 ;; vector of length 6?
560 (or (policy node (< safety 3)) ; no need in unsafe code
561 (and (array-type-p tspec) ; no need when no dimensions
562 (equal (array-type-dimensions tspec) '(*)))))
563 `(if (simple-vector-p x)
565 (replace (make-array (length x)) x)))
566 ;; FIXME: other VECTOR types?
568 (give-up-ir1-transform)))))))