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)
76 (give-up-ir1-transform)))))
78 ;;; Flush %TYPEP tests whose result is known at compile time.
79 (deftransform %typep ((object type))
80 (unless (constant-continuation-p type)
81 (give-up-ir1-transform))
82 (ir1-transform-type-predicate
84 (specifier-type (continuation-value type))))
86 ;;; This is the IR1 transform for simple type predicates. It checks
87 ;;; whether the single argument is known to (not) be of the
88 ;;; appropriate type, expanding to T or NIL as appropriate.
89 (deftransform fold-type-predicate ((object) * * :node node :defun-only t)
90 (let ((ctype (gethash (leaf-source-name
93 (basic-combination-fun node))))
94 *backend-predicate-types*)))
96 (ir1-transform-type-predicate object ctype)))
98 ;;; If FIND-CLASS is called on a constant class, locate the CLASS-CELL
100 (deftransform find-class ((name) ((constant-arg symbol)) *)
101 (let* ((name (continuation-value name))
102 (cell (find-class-cell name)))
103 `(or (class-cell-class ',cell)
104 (error "class not yet defined: ~S" name))))
106 ;;;; standard type predicates, i.e. those defined in package COMMON-LISP,
107 ;;;; plus at least one oddball (%INSTANCEP)
109 ;;;; Various other type predicates (e.g. low-level representation
110 ;;;; stuff like SIMPLE-ARRAY-SINGLE-FLOAT-P) are defined elsewhere.
112 ;;; FIXME: This function is only called once, at top level. Why not
113 ;;; just expand all its operations into toplevel code?
114 (defun !define-standard-type-predicates ()
115 (define-type-predicate arrayp array)
116 ; (The ATOM predicate is handled separately as (NOT CONS).)
117 (define-type-predicate bit-vector-p bit-vector)
118 (define-type-predicate characterp character)
119 (define-type-predicate compiled-function-p compiled-function)
120 (define-type-predicate complexp complex)
121 (define-type-predicate complex-rational-p (complex rational))
122 (define-type-predicate complex-float-p (complex float))
123 (define-type-predicate consp cons)
124 (define-type-predicate floatp float)
125 (define-type-predicate functionp function)
126 (define-type-predicate integerp integer)
127 (define-type-predicate keywordp keyword)
128 (define-type-predicate listp list)
129 (define-type-predicate null null)
130 (define-type-predicate numberp number)
131 (define-type-predicate rationalp rational)
132 (define-type-predicate realp real)
133 (define-type-predicate simple-bit-vector-p simple-bit-vector)
134 (define-type-predicate simple-string-p simple-string)
135 (define-type-predicate simple-vector-p simple-vector)
136 (define-type-predicate stringp string)
137 (define-type-predicate %instancep instance)
138 (define-type-predicate funcallable-instance-p funcallable-instance)
139 (define-type-predicate symbolp symbol)
140 (define-type-predicate vectorp vector))
141 (!define-standard-type-predicates)
143 ;;;; transforms for type predicates not implemented primitively
145 ;;;; See also VM dependent transforms.
147 (define-source-transform atom (x)
150 ;;;; TYPEP source transform
152 ;;; Return a form that tests the variable N-OBJECT for being in the
153 ;;; binds specified by TYPE. BASE is the name of the base type, for
154 ;;; declaration. We make SAFETY locally 0 to inhibit any checking of
156 #!-negative-zero-is-not-zero
157 (defun transform-numeric-bound-test (n-object type base)
158 (declare (type numeric-type type))
159 (let ((low (numeric-type-low type))
160 (high (numeric-type-high type)))
162 (declare (optimize (safety 0)))
165 `((> (the ,base ,n-object) ,(car low)))
166 `((>= (the ,base ,n-object) ,low))))
169 `((< (the ,base ,n-object) ,(car high)))
170 `((<= (the ,base ,n-object) ,high))))))))
172 #!+negative-zero-is-not-zero
173 (defun transform-numeric-bound-test (n-object type base)
174 (declare (type numeric-type type))
175 (let ((low (numeric-type-low type))
176 (high (numeric-type-high type))
177 (float-type-p (csubtypep type (specifier-type 'float)))
181 (declare (optimize (safety 0)))
184 `((let ((,x (the ,base ,n-object))
186 ,(if (not float-type-p)
188 `(if (and (zerop ,x) (zerop ,y))
189 (> (float-sign ,x) (float-sign ,y))
191 `((let ((,x (the ,base ,n-object))
193 ,(if (not float-type-p)
195 `(if (and (zerop ,x) (zerop ,y))
196 (>= (float-sign ,x) (float-sign ,y))
200 `((let ((,x (the ,base ,n-object))
202 ,(if (not float-type-p)
204 `(if (and (zerop ,x) (zerop ,y))
205 (< (float-sign ,x) (float-sign ,y))
207 `((let ((,x (the ,base ,n-object))
209 ,(if (not float-type-p)
211 `(if (and (zerop ,x) (zerop ,y))
212 (<= (float-sign ,x) (float-sign ,y))
215 ;;; Do source transformation of a test of a known numeric type. We can
216 ;;; assume that the type doesn't have a corresponding predicate, since
217 ;;; those types have already been picked off. In particular, CLASS
218 ;;; must be specified, since it is unspecified only in NUMBER and
219 ;;; COMPLEX. Similarly, we assume that COMPLEXP is always specified.
221 ;;; For non-complex types, we just test that the number belongs to the
222 ;;; base type, and then test that it is in bounds. When CLASS is
223 ;;; INTEGER, we check to see whether the range is no bigger than
224 ;;; FIXNUM. If so, we check for FIXNUM instead of INTEGER. This allows
225 ;;; us to use fixnum comparison to test the bounds.
227 ;;; For complex types, we must test for complex, then do the above on
228 ;;; both the real and imaginary parts. When CLASS is float, we need
229 ;;; only check the type of the realpart, since the format of the
230 ;;; realpart and the imagpart must be the same.
231 (defun source-transform-numeric-typep (object type)
232 (let* ((class (numeric-type-class type))
234 (integer (containing-integer-type type))
236 (float (or (numeric-type-format type) 'float))
238 (once-only ((n-object object))
239 (ecase (numeric-type-complexp type)
241 `(and (typep ,n-object ',base)
242 ,(transform-numeric-bound-test n-object type base)))
244 `(and (complexp ,n-object)
245 ,(once-only ((n-real `(realpart (the complex ,n-object)))
246 (n-imag `(imagpart (the complex ,n-object))))
249 (and (typep ,n-real ',base)
250 ,@(when (eq class 'integer)
251 `((typep ,n-imag ',base)))
252 ,(transform-numeric-bound-test n-real type base)
253 ,(transform-numeric-bound-test n-imag type
256 ;;; Do the source transformation for a test of a hairy type. AND,
257 ;;; SATISFIES and NOT are converted into the obvious code. We convert
258 ;;; unknown types to %TYPEP, emitting an efficiency note if
260 (defun source-transform-hairy-typep (object type)
261 (declare (type hairy-type type))
262 (let ((spec (hairy-type-specifier type)))
263 (cond ((unknown-type-p type)
264 (when (policy *lexenv* (> speed inhibit-warnings))
265 (compiler-note "can't open-code test of unknown type ~S"
266 (type-specifier type)))
267 `(%typep ,object ',spec))
270 (satisfies `(if (funcall #',(second spec) ,object) t nil))
272 (once-only ((n-obj object))
273 `(,(first spec) ,@(mapcar (lambda (x)
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 ;;; just drop through to the general code in this case, rather than
282 ;;; trying to optimize it.
283 (defun source-transform-union-typep (object type)
284 (let* ((types (union-type-types type))
285 (ltype (specifier-type 'list))
286 (mtype (find-if #'member-type-p types)))
287 (if (and mtype (csubtypep ltype type))
288 (let ((members (member-type-members mtype)))
289 (once-only ((n-obj object))
292 '(or ,@(mapcar #'type-specifier
293 (remove (specifier-type 'cons)
294 (remove mtype types)))
295 (member ,@(remove nil members)))))))
296 (once-only ((n-obj object))
297 `(or ,@(mapcar (lambda (x)
298 `(typep ,n-obj ',(type-specifier x)))
301 ;;; Do source transformation for TYPEP of a known intersection type.
302 (defun source-transform-intersection-typep (object type)
303 (once-only ((n-obj object))
304 `(and ,@(mapcar (lambda (x)
305 `(typep ,n-obj ',(type-specifier x)))
306 (intersection-type-types type)))))
308 ;;; If necessary recurse to check the cons type.
309 (defun source-transform-cons-typep (object type)
310 (let* ((car-type (cons-type-car-type type))
311 (cdr-type (cons-type-cdr-type type)))
312 (let ((car-test-p (not (or (type= car-type *wild-type*)
313 (type= car-type (specifier-type t)))))
314 (cdr-test-p (not (or (type= cdr-type *wild-type*)
315 (type= cdr-type (specifier-type t))))))
316 (if (and (not car-test-p) (not cdr-test-p))
318 (once-only ((n-obj object))
321 `((typep (car ,n-obj)
322 ',(type-specifier car-type))))
324 `((typep (cdr ,n-obj)
325 ',(type-specifier cdr-type))))))))))
327 ;;; Return the predicate and type from the most specific entry in
328 ;;; *TYPE-PREDICATES* that is a supertype of TYPE.
329 (defun find-supertype-predicate (type)
330 (declare (type ctype type))
333 (dolist (x *backend-type-predicates*)
334 (let ((stype (car x)))
335 (when (and (csubtypep type stype)
337 (csubtypep stype res-type)))
338 (setq res-type stype)
339 (setq res (cdr x)))))
340 (values res res-type)))
342 ;;; Return forms to test that OBJ has the rank and dimensions
343 ;;; specified by TYPE, where STYPE is the type we have checked against
344 ;;; (which is the same but for dimensions.)
345 (defun test-array-dimensions (obj type stype)
346 (declare (type array-type type stype))
347 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
348 (dims (array-type-dimensions type)))
351 (when (eq (array-type-dimensions stype) '*)
352 (res `(= (array-rank ,obj) ,(length dims))))
354 (dim dims (cdr dim)))
356 (let ((dim (car dim)))
358 (res `(= (array-dimension ,obj ,i) ,dim)))))
361 ;;; If we can find a type predicate that tests for the type without
362 ;;; dimensions, then use that predicate and test for dimensions.
363 ;;; Otherwise, just do %TYPEP.
364 (defun source-transform-array-typep (obj type)
365 (multiple-value-bind (pred stype) (find-supertype-predicate type)
366 (if (and (array-type-p stype)
367 ;; (If the element type hasn't been defined yet, it's
368 ;; not safe to assume here that it will eventually
369 ;; have (UPGRADED-ARRAY-ELEMENT-TYPE type)=T, so punt.)
370 (not (unknown-type-p (array-type-element-type type)))
371 (type= (array-type-specialized-element-type stype)
372 (array-type-specialized-element-type type))
373 (eq (array-type-complexp stype) (array-type-complexp type)))
374 (once-only ((n-obj obj))
376 ,@(test-array-dimensions n-obj type stype)))
377 `(%typep ,obj ',(type-specifier type)))))
379 ;;; Transform a type test against some instance type. The type test is
380 ;;; flushed if the result is known at compile time. If not properly
381 ;;; named, error. If sealed and has no subclasses, just test for
382 ;;; layout-EQ. If a structure then test for layout-EQ and then a
383 ;;; general test based on layout-inherits. If safety is important,
384 ;;; then we also check whether the layout for the object is invalid
385 ;;; and signal an error if so. Otherwise, look up the indirect
386 ;;; class-cell and call CLASS-CELL-TYPEP at runtime.
387 (deftransform %instance-typep ((object spec) (* *) * :node node)
388 (aver (constant-continuation-p spec))
389 (let* ((spec (continuation-value spec))
390 (class (specifier-type spec))
391 (name (sb!xc:class-name class))
392 (otype (continuation-type object))
393 (layout (let ((res (info :type :compiler-layout name)))
394 (if (and res (not (layout-invalid res)))
398 ;; Flush tests whose result is known at compile time.
399 ((not (types-equal-or-intersect otype class))
401 ((csubtypep otype class)
403 ;; If not properly named, error.
404 ((not (and name (eq (sb!xc:find-class name) class)))
405 (compiler-error "can't compile TYPEP of anonymous or undefined ~
409 ;; Delay the type transform to give type propagation a chance.
410 (delay-ir1-transform node :constraint)
412 ;; Otherwise transform the type test.
413 (multiple-value-bind (pred get-layout)
415 ((csubtypep class (specifier-type 'funcallable-instance))
416 (values 'funcallable-instance-p '%funcallable-instance-layout))
417 ((csubtypep class (specifier-type 'instance))
418 (values '%instancep '%instance-layout))
420 (values '(lambda (x) (declare (ignore x)) t) 'layout-of)))
422 ((and (eq (class-state class) :sealed) layout
423 (not (class-subclasses class)))
424 ;; Sealed and has no subclasses.
425 (let ((n-layout (gensym)))
427 (let ((,n-layout (,get-layout object)))
428 ,@(when (policy *lexenv* (>= safety speed))
429 `((when (layout-invalid ,n-layout)
430 (%layout-invalid-error object ',layout))))
431 (eq ,n-layout ',layout)))))
432 ((and (typep class 'basic-structure-class) layout)
433 ;; structure type tests; hierarchical layout depths
434 (let ((depthoid (layout-depthoid layout))
437 (let ((,n-layout (,get-layout object)))
438 ,@(when (policy *lexenv* (>= safety speed))
439 `((when (layout-invalid ,n-layout)
440 (%layout-invalid-error object ',layout))))
441 (if (eq ,n-layout ',layout)
443 (and (> (layout-depthoid ,n-layout)
445 (locally (declare (optimize (safety 0)))
446 (eq (svref (layout-inherits ,n-layout)
449 ((and layout (>= (layout-depthoid layout) 0))
450 ;; hierarchical layout depths for other things (e.g.
452 (let ((depthoid (layout-depthoid layout))
454 (n-inherits (gensym)))
456 (let ((,n-layout (,get-layout object)))
457 ,@(when (policy *lexenv* (>= safety speed))
458 `((when (layout-invalid ,n-layout)
459 (%layout-invalid-error object ',layout))))
460 (if (eq ,n-layout ',layout)
462 (let ((,n-inherits (layout-inherits ,n-layout)))
463 (declare (optimize (safety 0)))
464 (and (> (length ,n-inherits) ,depthoid)
465 (eq (svref ,n-inherits ,depthoid)
468 (/noshow "default case -- ,PRED and CLASS-CELL-TYPEP")
470 (class-cell-typep (,get-layout object)
471 ',(find-class-cell name)
474 ;;; If the specifier argument is a quoted constant, then we consider
475 ;;; converting into a simple predicate or other stuff. If the type is
476 ;;; constant, but we can't transform the call, then we convert to
477 ;;; %TYPEP. We only pass when the type is non-constant. This allows us
478 ;;; to recognize between calls that might later be transformed
479 ;;; successfully when a constant type is discovered. We don't give an
480 ;;; efficiency note when we pass, since the IR1 transform will give
481 ;;; one if necessary and appropriate.
483 ;;; If the type is TYPE= to a type that has a predicate, then expand
484 ;;; to that predicate. Otherwise, we dispatch off of the type's type.
485 ;;; These transformations can increase space, but it is hard to tell
486 ;;; when, so we ignore policy and always do them.
487 (define-source-transform typep (object spec)
488 ;; KLUDGE: It looks bad to only do this on explicitly quoted forms,
489 ;; since that would overlook other kinds of constants. But it turns
490 ;; out that the DEFTRANSFORM for TYPEP detects any constant
491 ;; continuation, transforms it into a quoted form, and gives this
492 ;; source transform another chance, so it all works out OK, in a
493 ;; weird roundabout way. -- WHN 2001-03-18
494 (if (and (consp spec) (eq (car spec) 'quote))
495 (let ((type (specifier-type (cadr spec))))
496 (or (let ((pred (cdr (assoc type *backend-type-predicates*
498 (when pred `(,pred ,object)))
501 (source-transform-hairy-typep object type))
503 (source-transform-union-typep object type))
505 (source-transform-intersection-typep object type))
507 `(member ,object ',(member-type-members type)))
509 (compiler-warn "illegal type specifier for TYPEP: ~S"
511 `(%typep ,object ,spec))
515 (source-transform-numeric-typep object type))
517 `(%instance-typep ,object ,spec))
519 (source-transform-array-typep object type))
521 (source-transform-cons-typep object type))
523 `(%typep ,object ,spec)))
528 (deftransform coerce ((x type) (* *) *)
529 (unless (constant-continuation-p type)
530 (give-up-ir1-transform))
531 (let ((tspec (specifier-type (continuation-value type))))
532 (if (csubtypep (continuation-type x) tspec)
534 ;; Note: The THE here makes sure that specifiers like
535 ;; (SINGLE-FLOAT 0.0 1.0) can raise a TYPE-ERROR.
536 `(the ,(continuation-value type)
538 ((csubtypep tspec (specifier-type 'double-float))
540 ;; FIXME: #!+long-float (t ,(error "LONG-FLOAT case needed"))
541 ((csubtypep tspec (specifier-type 'float))
543 ((csubtypep tspec (specifier-type 'simple-vector))
544 '(coerce-to-simple-vector x))
546 (give-up-ir1-transform)))))))