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) * * :node node)
61 (unless (constant-lvar-p type)
62 (give-up-ir1-transform "can't open-code test of non-constant type"))
63 (multiple-value-bind (expansion fail-p)
64 (source-transform-typep 'object (lvar-value type))
69 ;;; If the lvar OBJECT definitely is or isn't of the specified
70 ;;; type, then return T or NIL as appropriate. Otherwise quietly
71 ;;; GIVE-UP-IR1-TRANSFORM.
72 (defun ir1-transform-type-predicate (object type)
73 (declare (type lvar object) (type ctype type))
74 (let ((otype (lvar-type object)))
75 (cond ((not (types-equal-or-intersect otype type))
77 ((csubtypep otype type)
79 ((eq type *empty-type*)
82 (give-up-ir1-transform)))))
84 ;;; Flush %TYPEP tests whose result is known at compile time.
85 (deftransform %typep ((object type))
86 (unless (constant-lvar-p type)
87 (give-up-ir1-transform))
88 (ir1-transform-type-predicate
90 (ir1-transform-specifier-type (lvar-value type))))
92 ;;; This is the IR1 transform for simple type predicates. It checks
93 ;;; whether the single argument is known to (not) be of the
94 ;;; appropriate type, expanding to T or NIL as appropriate.
95 (deftransform fold-type-predicate ((object) * * :node node :defun-only t)
96 (let ((ctype (gethash (leaf-source-name
99 (basic-combination-fun node))))
100 *backend-predicate-types*)))
102 (ir1-transform-type-predicate object ctype)))
104 ;;; If FIND-CLASS is called on a constant class, locate the CLASS-CELL
106 (deftransform find-classoid ((name) ((constant-arg symbol)) *)
107 (let* ((name (lvar-value name))
108 (cell (find-classoid-cell name)))
109 `(or (classoid-cell-classoid ',cell)
110 (error "class not yet defined: ~S" name))))
112 ;;;; standard type predicates, i.e. those defined in package COMMON-LISP,
113 ;;;; plus at least one oddball (%INSTANCEP)
115 ;;;; Various other type predicates (e.g. low-level representation
116 ;;;; stuff like SIMPLE-ARRAY-SINGLE-FLOAT-P) are defined elsewhere.
118 ;;; FIXME: This function is only called once, at top level. Why not
119 ;;; just expand all its operations into toplevel code?
120 (defun !define-standard-type-predicates ()
121 (define-type-predicate arrayp array)
122 ; (The ATOM predicate is handled separately as (NOT CONS).)
123 (define-type-predicate bit-vector-p bit-vector)
124 (define-type-predicate characterp character)
125 (define-type-predicate compiled-function-p compiled-function)
126 (define-type-predicate complexp complex)
127 (define-type-predicate complex-rational-p (complex rational))
128 (define-type-predicate complex-float-p (complex float))
129 (define-type-predicate consp cons)
130 (define-type-predicate floatp float)
131 (define-type-predicate functionp function)
132 (define-type-predicate integerp integer)
133 (define-type-predicate keywordp keyword)
134 (define-type-predicate listp list)
135 (define-type-predicate null null)
136 (define-type-predicate numberp number)
137 (define-type-predicate rationalp rational)
138 (define-type-predicate realp real)
139 (define-type-predicate simple-bit-vector-p simple-bit-vector)
140 (define-type-predicate simple-string-p simple-string)
141 (define-type-predicate simple-vector-p simple-vector)
142 (define-type-predicate stringp string)
143 (define-type-predicate %instancep instance)
144 (define-type-predicate funcallable-instance-p funcallable-instance)
145 (define-type-predicate symbolp symbol)
146 (define-type-predicate vectorp vector))
147 (!define-standard-type-predicates)
149 ;;;; transforms for type predicates not implemented primitively
151 ;;;; See also VM dependent transforms.
153 (define-source-transform atom (x)
156 (define-source-transform base-char-p (x)
157 `(typep ,x 'base-char))
159 ;;;; TYPEP source transform
161 ;;; Return a form that tests the variable N-OBJECT for being in the
162 ;;; binds specified by TYPE. BASE is the name of the base type, for
163 ;;; declaration. We make SAFETY locally 0 to inhibit any checking of
165 (defun transform-numeric-bound-test (n-object type base)
166 (declare (type numeric-type type))
167 (let ((low (numeric-type-low type))
168 (high (numeric-type-high type)))
170 (declare (optimize (safety 0)))
173 `((> (truly-the ,base ,n-object) ,(car low)))
174 `((>= (truly-the ,base ,n-object) ,low))))
177 `((< (truly-the ,base ,n-object) ,(car high)))
178 `((<= (truly-the ,base ,n-object) ,high))))))))
180 ;;; Do source transformation of a test of a known numeric type. We can
181 ;;; assume that the type doesn't have a corresponding predicate, since
182 ;;; those types have already been picked off. In particular, CLASS
183 ;;; must be specified, since it is unspecified only in NUMBER and
184 ;;; COMPLEX. Similarly, we assume that COMPLEXP is always specified.
186 ;;; For non-complex types, we just test that the number belongs to the
187 ;;; base type, and then test that it is in bounds. When CLASS is
188 ;;; INTEGER, we check to see whether the range is no bigger than
189 ;;; FIXNUM. If so, we check for FIXNUM instead of INTEGER. This allows
190 ;;; us to use fixnum comparison to test the bounds.
192 ;;; For complex types, we must test for complex, then do the above on
193 ;;; both the real and imaginary parts. When CLASS is float, we need
194 ;;; only check the type of the realpart, since the format of the
195 ;;; realpart and the imagpart must be the same.
196 (defun source-transform-numeric-typep (object type)
197 (let* ((class (numeric-type-class type))
199 (integer (containing-integer-type
200 (if (numeric-type-complexp type)
201 (modified-numeric-type type
205 (float (or (numeric-type-format type) 'float))
207 (once-only ((n-object object))
208 (ecase (numeric-type-complexp type)
210 `(and (typep ,n-object ',base)
211 ,(transform-numeric-bound-test n-object type base)))
213 `(and (complexp ,n-object)
214 ,(once-only ((n-real `(realpart (truly-the complex ,n-object)))
215 (n-imag `(imagpart (truly-the complex ,n-object))))
218 (and (typep ,n-real ',base)
219 ,@(when (eq class 'integer)
220 `((typep ,n-imag ',base)))
221 ,(transform-numeric-bound-test n-real type base)
222 ,(transform-numeric-bound-test n-imag type
225 ;;; Do the source transformation for a test of a hairy type. AND,
226 ;;; SATISFIES and NOT are converted into the obvious code. We convert
227 ;;; unknown types to %TYPEP, emitting an efficiency note if
229 (defun source-transform-hairy-typep (object type)
230 (declare (type hairy-type type))
231 (let ((spec (hairy-type-specifier type)))
232 (cond ((unknown-type-p type)
233 (when (policy *lexenv* (> speed inhibit-warnings))
234 (compiler-notify "can't open-code test of unknown type ~S"
235 (type-specifier type)))
236 `(%typep ,object ',spec))
239 (satisfies `(if (funcall #',(second spec) ,object) t nil))
241 (once-only ((n-obj object))
242 `(,(first spec) ,@(mapcar (lambda (x)
246 (defun source-transform-negation-typep (object type)
247 (declare (type negation-type type))
248 (let ((spec (type-specifier (negation-type-type type))))
249 `(not (typep ,object ',spec))))
251 ;;; Do source transformation for TYPEP of a known union type. If a
252 ;;; union type contains LIST, then we pull that out and make it into a
253 ;;; single LISTP call. Note that if SYMBOL is in the union, then LIST
254 ;;; will be a subtype even without there being any (member NIL). We
255 ;;; currently just drop through to the general code in this case,
256 ;;; rather than trying to optimize it (but FIXME CSR 2004-04-05: it
257 ;;; wouldn't be hard to optimize it after all).
258 (defun source-transform-union-typep (object type)
259 (let* ((types (union-type-types type))
260 (type-cons (specifier-type 'cons))
261 (mtype (find-if #'member-type-p types))
262 (members (when mtype (member-type-members mtype))))
265 (memq type-cons types))
266 (once-only ((n-obj object))
269 '(or ,@(mapcar #'type-specifier
271 (remove mtype types)))
272 (member ,@(remove nil members))))))
273 (once-only ((n-obj object))
274 `(or ,@(mapcar (lambda (x)
275 `(typep ,n-obj ',(type-specifier x)))
278 ;;; Do source transformation for TYPEP of a known intersection type.
279 (defun source-transform-intersection-typep (object type)
280 (once-only ((n-obj object))
281 `(and ,@(mapcar (lambda (x)
282 `(typep ,n-obj ',(type-specifier x)))
283 (intersection-type-types type)))))
285 ;;; If necessary recurse to check the cons type.
286 (defun source-transform-cons-typep (object type)
287 (let* ((car-type (cons-type-car-type type))
288 (cdr-type (cons-type-cdr-type type)))
289 (let ((car-test-p (not (type= car-type *universal-type*)))
290 (cdr-test-p (not (type= cdr-type *universal-type*))))
291 (if (and (not car-test-p) (not cdr-test-p))
293 (once-only ((n-obj object))
296 `((typep (car ,n-obj)
297 ',(type-specifier car-type))))
299 `((typep (cdr ,n-obj)
300 ',(type-specifier cdr-type))))))))))
302 (defun source-transform-character-set-typep (object type)
303 (let ((pairs (character-set-type-pairs type)))
304 (if (and (= (length pairs) 1)
306 (= (cdar pairs) (1- sb!xc:char-code-limit)))
307 `(characterp ,object)
308 (once-only ((n-obj object))
309 (let ((n-code (gensym "CODE")))
310 `(and (characterp ,n-obj)
311 (let ((,n-code (sb!xc:char-code ,n-obj)))
313 ,@(loop for pair in pairs
315 `(<= ,(car pair) ,n-code ,(cdr pair)))))))))))
317 ;;; Return the predicate and type from the most specific entry in
318 ;;; *TYPE-PREDICATES* that is a supertype of TYPE.
319 (defun find-supertype-predicate (type)
320 (declare (type ctype type))
323 (dolist (x *backend-type-predicates*)
324 (let ((stype (car x)))
325 (when (and (csubtypep type stype)
327 (csubtypep stype res-type)))
328 (setq res-type stype)
329 (setq res (cdr x)))))
330 (values res res-type)))
332 ;;; Return forms to test that OBJ has the rank and dimensions
333 ;;; specified by TYPE, where STYPE is the type we have checked against
334 ;;; (which is the same but for dimensions and element type).
335 (defun test-array-dimensions (obj type stype)
336 (declare (type array-type type stype))
337 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
338 (dims (array-type-dimensions type)))
339 (unless (or (eq dims '*)
340 (equal dims (array-type-dimensions stype)))
342 (when (eq (array-type-dimensions stype) '*)
343 (res `(= (array-rank ,obj) ,(length dims))))
345 (dim dims (cdr dim)))
347 (let ((dim (car dim)))
349 (res `(= (array-dimension ,obj ,i) ,dim)))))
352 ;;; Return forms to test that OBJ has the element-type specified by
353 ;;; type specified by TYPE, where STYPE is the type we have checked
354 ;;; against (which is the same but for dimensions and element type).
355 (defun test-array-element-type (obj type stype)
356 (declare (type array-type type stype))
357 (let ((obj `(truly-the ,(type-specifier stype) ,obj))
358 (eltype (array-type-specialized-element-type type)))
359 (unless (type= eltype (array-type-specialized-element-type stype))
360 (with-unique-names (data)
361 `((do ((,data ,obj (%array-data-vector ,data)))
362 ((not (array-header-p ,data))
363 ;; KLUDGE: this isn't in fact maximally efficient,
364 ;; because though we know that DATA is a (SIMPLE-ARRAY *
365 ;; (*)), we will still check to see if the lowtag is
368 '(simple-array ,(type-specifier eltype) (*))))))))))
370 ;;; If we can find a type predicate that tests for the type without
371 ;;; dimensions, then use that predicate and test for dimensions.
372 ;;; Otherwise, just do %TYPEP.
373 (defun source-transform-array-typep (obj type)
374 (multiple-value-bind (pred stype) (find-supertype-predicate type)
375 (if (and (array-type-p stype)
376 ;; (If the element type hasn't been defined yet, it's
377 ;; not safe to assume here that it will eventually
378 ;; have (UPGRADED-ARRAY-ELEMENT-TYPE type)=T, so punt.)
379 (not (unknown-type-p (array-type-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 ,@(test-array-element-type n-obj type stype)))
385 `(%typep ,obj ',(type-specifier type)))))
387 ;;; Transform a type test against some instance type. The type test is
388 ;;; flushed if the result is known at compile time. If not properly
389 ;;; named, error. If sealed and has no subclasses, just test for
390 ;;; layout-EQ. If a structure then test for layout-EQ and then a
391 ;;; general test based on layout-inherits. If safety is important,
392 ;;; then we also check whether the layout for the object is invalid
393 ;;; and signal an error if so. Otherwise, look up the indirect
394 ;;; class-cell and call CLASS-CELL-TYPEP at runtime.
395 (deftransform %instance-typep ((object spec) (* *) * :node node)
396 (aver (constant-lvar-p spec))
397 (let* ((spec (lvar-value spec))
398 (class (specifier-type spec))
399 (name (classoid-name class))
400 (otype (lvar-type object))
401 (layout (let ((res (info :type :compiler-layout name)))
402 (if (and res (not (layout-invalid res)))
406 ;; Flush tests whose result is known at compile time.
407 ((not (types-equal-or-intersect otype class))
409 ((csubtypep otype class)
411 ;; If not properly named, error.
412 ((not (and name (eq (find-classoid name) class)))
413 (compiler-error "can't compile TYPEP of anonymous or undefined ~
417 ;; Delay the type transform to give type propagation a chance.
418 (delay-ir1-transform node :constraint)
420 ;; Otherwise transform the type test.
421 (multiple-value-bind (pred get-layout)
423 ((csubtypep class (specifier-type 'funcallable-instance))
424 (values 'funcallable-instance-p '%funcallable-instance-layout))
425 ((csubtypep class (specifier-type 'instance))
426 (values '%instancep '%instance-layout))
428 (values '(lambda (x) (declare (ignore x)) t) 'layout-of)))
430 ((and (eq (classoid-state class) :sealed) layout
431 (not (classoid-subclasses class)))
432 ;; Sealed and has no subclasses.
433 (let ((n-layout (gensym)))
435 (let ((,n-layout (,get-layout object)))
436 ,@(when (policy *lexenv* (>= safety speed))
437 `((when (layout-invalid ,n-layout)
438 (%layout-invalid-error object ',layout))))
439 (eq ,n-layout ',layout)))))
440 ((and (typep class 'structure-classoid) layout)
441 ;; structure type tests; hierarchical layout depths
442 (let ((depthoid (layout-depthoid layout))
445 (let ((,n-layout (,get-layout object)))
446 ;; we used to check for invalid layouts here,
447 ;; but in fact that's both unnecessary and
448 ;; wrong; it's unnecessary because structure
449 ;; classes can't be redefined, and it's wrong
450 ;; because it is quite legitimate to pass an
451 ;; object with an invalid layout to a structure
453 (if (eq ,n-layout ',layout)
455 (and (> (layout-depthoid ,n-layout)
457 (locally (declare (optimize (safety 0)))
458 (eq (svref (layout-inherits ,n-layout)
461 ((and layout (>= (layout-depthoid layout) 0))
462 ;; hierarchical layout depths for other things (e.g.
463 ;; CONDITION, STREAM)
464 (let ((depthoid (layout-depthoid layout))
466 (n-inherits (gensym)))
468 (let ((,n-layout (,get-layout object)))
469 (when (layout-invalid ,n-layout)
470 (setq ,n-layout (update-object-layout-or-invalid
472 (if (eq ,n-layout ',layout)
474 (let ((,n-inherits (layout-inherits ,n-layout)))
475 (declare (optimize (safety 0)))
476 (and (> (length ,n-inherits) ,depthoid)
477 (eq (svref ,n-inherits ,depthoid)
480 (/noshow "default case -- ,PRED and CLASS-CELL-TYPEP")
482 (classoid-cell-typep (,get-layout object)
483 ',(find-classoid-cell name)
486 ;;; If the specifier argument is a quoted constant, then we consider
487 ;;; converting into a simple predicate or other stuff. If the type is
488 ;;; constant, but we can't transform the call, then we convert to
489 ;;; %TYPEP. We only pass when the type is non-constant. This allows us
490 ;;; to recognize between calls that might later be transformed
491 ;;; successfully when a constant type is discovered. We don't give an
492 ;;; efficiency note when we pass, since the IR1 transform will give
493 ;;; one if necessary and appropriate.
495 ;;; If the type is TYPE= to a type that has a predicate, then expand
496 ;;; to that predicate. Otherwise, we dispatch off of the type's type.
497 ;;; These transformations can increase space, but it is hard to tell
498 ;;; when, so we ignore policy and always do them.
499 (defun source-transform-typep (object type)
500 (let ((ctype (careful-specifier-type type)))
501 (or (when (not ctype)
502 (compiler-warn "illegal type specifier for TYPEP: ~S" type)
503 (return-from source-transform-typep (values nil t)))
504 (let ((pred (cdr (assoc ctype *backend-type-predicates*
506 (when pred `(,pred ,object)))
509 (source-transform-hairy-typep object ctype))
511 (source-transform-negation-typep object ctype))
513 (source-transform-union-typep object ctype))
515 (source-transform-intersection-typep object ctype))
517 `(if (member ,object ',(member-type-members ctype)) t))
519 (compiler-warn "illegal type specifier for TYPEP: ~S" type)
520 (return-from source-transform-typep (values nil t)))
524 (source-transform-numeric-typep object ctype))
526 `(%instance-typep ,object ',type))
528 (source-transform-array-typep object ctype))
530 (source-transform-cons-typep object ctype))
532 (source-transform-character-set-typep object ctype))
534 `(%typep ,object ',type))))
536 (define-source-transform typep (object spec)
537 ;; KLUDGE: It looks bad to only do this on explicitly quoted forms,
538 ;; since that would overlook other kinds of constants. But it turns
539 ;; out that the DEFTRANSFORM for TYPEP detects any constant
540 ;; lvar, transforms it into a quoted form, and gives this
541 ;; source transform another chance, so it all works out OK, in a
542 ;; weird roundabout way. -- WHN 2001-03-18
543 (if (and (consp spec) (eq (car spec) 'quote))
544 (source-transform-typep object (cadr spec))
549 ;;; Constant-folding.
552 (defoptimizer (coerce optimizer) ((x type) node)
553 (when (and (constant-lvar-p x) (constant-lvar-p type))
554 (let ((value (lvar-value x)))
555 (when (or (numberp value) (characterp value))
556 (constant-fold-call node)
559 (deftransform coerce ((x type) (* *) * :node node)
560 (unless (constant-lvar-p type)
561 (give-up-ir1-transform))
562 (let ((tspec (ir1-transform-specifier-type (lvar-value type))))
563 (if (csubtypep (lvar-type x) tspec)
565 ;; Note: The THE here makes sure that specifiers like
566 ;; (SINGLE-FLOAT 0.0 1.0) can raise a TYPE-ERROR.
567 `(the ,(lvar-value type)
569 ((csubtypep tspec (specifier-type 'double-float))
571 ;; FIXME: #!+long-float (t ,(error "LONG-FLOAT case needed"))
572 ((csubtypep tspec (specifier-type 'float))
574 ((and (csubtypep tspec (specifier-type 'simple-vector))
575 ;; Can we avoid checking for dimension issues like
576 ;; (COERCE FOO '(SIMPLE-VECTOR 5)) returning a
577 ;; vector of length 6?
578 (or (policy node (< safety 3)) ; no need in unsafe code
579 (and (array-type-p tspec) ; no need when no dimensions
580 (equal (array-type-dimensions tspec) '(*)))))
581 `(if (simple-vector-p x)
583 (replace (make-array (length x)) x)))
584 ;; FIXME: other VECTOR types?
586 (give-up-ir1-transform)))))))