1 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; This software is derived from the CMU CL system, which was
5 ;;;; written at Carnegie Mellon University and released into the
6 ;;;; public domain. The software is in the public domain and is
7 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
8 ;;;; files for more information.
10 (in-package "SB!KERNEL")
12 (!begin-collecting-cold-init-forms)
14 ;;; Has the type system been properly initialized? (I.e. is it OK to
16 (defvar *type-system-initialized* #+sb-xc-host nil) ; (set in cold load)
18 ;;;; representations of types
20 ;;; A HAIRY-TYPE represents anything too weird to be described
21 ;;; reasonably or to be useful, such as NOT, SATISFIES, unknown types,
22 ;;; and unreasonably complicated types involving AND. We just remember
23 ;;; the original type spec.
24 (defstruct (hairy-type (:include ctype
25 (class-info (type-class-or-lose 'hairy))
27 (might-contain-other-types-p t))
30 ;; the Common Lisp type-specifier of the type we represent
31 (specifier nil :type t))
33 (!define-type-class hairy)
35 ;;; An UNKNOWN-TYPE is a type not known to the type system (not yet
36 ;;; defined). We make this distinction since we don't want to complain
37 ;;; about types that are hairy but defined.
38 (defstruct (unknown-type (:include hairy-type)
41 (defstruct (negation-type (:include ctype
42 (class-info (type-class-or-lose 'negation))
43 ;; FIXME: is this right? It's
44 ;; what they had before, anyway
46 (might-contain-other-types-p t))
49 (type (missing-arg) :type ctype))
51 (!define-type-class negation)
53 ;;; ARGS-TYPE objects are used both to represent VALUES types and
54 ;;; to represent FUNCTION types.
55 (defstruct (args-type (:include ctype)
58 ;; Lists of the type for each required and optional argument.
59 (required nil :type list)
60 (optional nil :type list)
61 ;; The type for the rest arg. NIL if there is no &REST arg.
62 (rest nil :type (or ctype null))
63 ;; true if &KEY arguments are specified
64 (keyp nil :type boolean)
65 ;; list of KEY-INFO structures describing the &KEY arguments
66 (keywords nil :type list)
67 ;; true if other &KEY arguments are allowed
68 (allowp nil :type boolean))
70 (defun canonicalize-args-type-args (required optional rest)
72 (let ((last-distinct-optional (position rest optional
76 (when last-distinct-optional
77 (subseq optional 0 (1+ last-distinct-optional))))))
78 (values required optional rest))
80 (defun args-types (lambda-list-like-thing)
82 (required optional restp rest keyp keys allowp auxp aux)
83 (parse-lambda-list-like-thing lambda-list-like-thing)
84 (declare (ignore aux))
86 (error "&AUX in a FUNCTION or VALUES type: ~S." lambda-list-like-thing))
87 (let ((required (mapcar #'single-value-specifier-type required))
88 (optional (mapcar #'single-value-specifier-type optional))
89 (rest (when restp (single-value-specifier-type rest)))
93 (unless (proper-list-of-length-p key 2)
94 (error "Keyword type description is not a two-list: ~S." key))
95 (let ((kwd (first key)))
96 (when (find kwd (key-info) :key #'key-info-name)
97 (error "~@<repeated keyword ~S in lambda list: ~2I~_~S~:>"
98 kwd lambda-list-like-thing))
102 :type (single-value-specifier-type (second key))))))
104 (multiple-value-bind (required optional rest)
105 (canonicalize-args-type-args required optional rest)
106 (values required optional rest keyp keywords allowp)))))
108 (defstruct (values-type
110 (class-info (type-class-or-lose 'values)))
111 (:constructor %make-values-type)
114 (defun make-values-type (&rest initargs
115 &key (args nil argsp) &allow-other-keys)
119 (multiple-value-bind (required optional rest keyp keywords allowp)
121 (if (and (null required)
123 (eq rest *universal-type*)
126 (%make-values-type :required required
132 (apply #'%make-values-type initargs)))
134 (!define-type-class values)
136 ;;; (SPECIFIER-TYPE 'FUNCTION) and its subtypes
137 (defstruct (fun-type (:include args-type
138 (class-info (type-class-or-lose 'function)))
139 (:constructor %make-fun-type))
140 ;; true if the arguments are unrestrictive, i.e. *
141 (wild-args nil :type boolean)
142 ;; type describing the return values. This is a values type
143 ;; when multiple values were specified for the return.
144 (returns (missing-arg) :type ctype))
145 (defun make-fun-type (&rest initargs
146 &key (args nil argsp) returns &allow-other-keys)
149 (if (eq returns *wild-type*)
150 (specifier-type 'function)
151 (%make-fun-type :wild-args t :returns returns))
152 (multiple-value-bind (required optional rest keyp keywords allowp)
154 (if (and (null required)
156 (eq rest *universal-type*)
158 (if (eq returns *wild-type*)
159 (specifier-type 'function)
160 (%make-fun-type :wild-args t :returns returns))
161 (%make-fun-type :required required
168 ;; FIXME: are we really sure that we won't make something that
169 ;; looks like a completely wild function here?
170 (apply #'%make-fun-type initargs)))
172 ;;; The CONSTANT-TYPE structure represents a use of the CONSTANT-ARG
173 ;;; "type specifier", which is only meaningful in function argument
174 ;;; type specifiers used within the compiler. (It represents something
175 ;;; that the compiler knows to be a constant.)
176 (defstruct (constant-type
178 (class-info (type-class-or-lose 'constant)))
180 ;; The type which the argument must be a constant instance of for this type
182 (type (missing-arg) :type ctype))
184 ;;; The NAMED-TYPE is used to represent *, T and NIL. These types must
185 ;;; be super- or sub-types of all types, not just classes and * and
186 ;;; NIL aren't classes anyway, so it wouldn't make much sense to make
187 ;;; them built-in classes.
188 (defstruct (named-type (:include ctype
189 (class-info (type-class-or-lose 'named)))
191 (name nil :type symbol))
193 ;;; a list of all the float "formats" (i.e. internal representations;
194 ;;; nothing to do with #'FORMAT), in order of decreasing precision
195 (eval-when (:compile-toplevel :load-toplevel :execute)
196 (defparameter *float-formats*
197 '(long-float double-float single-float short-float)))
199 ;;; The type of a float format.
200 (deftype float-format () `(member ,@*float-formats*))
202 ;;; A NUMERIC-TYPE represents any numeric type, including things
204 (defstruct (numeric-type (:include ctype
205 (class-info (type-class-or-lose 'number)))
206 (:constructor %make-numeric-type)
208 ;; the kind of numeric type we have, or NIL if not specified (just
209 ;; NUMBER or COMPLEX)
211 ;; KLUDGE: A slot named CLASS for a non-CLASS value is bad.
212 ;; Especially when a CLASS value *is* stored in another slot (called
213 ;; CLASS-INFO:-). Perhaps this should be called CLASS-NAME? Also
214 ;; weird that comment above says "Numeric-Type is used to represent
215 ;; all numeric types" but this slot doesn't allow COMPLEX as an
216 ;; option.. how does this fall into "not specified" NIL case above?
217 ;; Perhaps someday we can switch to CLOS and make NUMERIC-TYPE
218 ;; be an abstract base class and INTEGER-TYPE, RATIONAL-TYPE, and
219 ;; whatnot be concrete subclasses..
220 (class nil :type (member integer rational float nil) :read-only t)
221 ;; "format" for a float type (i.e. type specifier for a CPU
222 ;; representation of floating point, e.g. 'SINGLE-FLOAT -- nothing
223 ;; to do with #'FORMAT), or NIL if not specified or not a float.
224 ;; Formats which don't exist in a given implementation don't appear
226 (format nil :type (or float-format null) :read-only t)
227 ;; Is this a complex numeric type? Null if unknown (only in NUMBER).
229 ;; FIXME: I'm bewildered by FOO-P names for things not intended to
230 ;; interpreted as truth values. Perhaps rename this COMPLEXNESS?
231 (complexp :real :type (member :real :complex nil) :read-only t)
232 ;; The upper and lower bounds on the value, or NIL if there is no
233 ;; bound. If a list of a number, the bound is exclusive. Integer
234 ;; types never have exclusive bounds, i.e. they may have them on
235 ;; input, but they're canonicalized to inclusive bounds before we
237 (low nil :type (or number cons null) :read-only t)
238 (high nil :type (or number cons null) :read-only t))
240 ;;; Impose canonicalization rules for NUMERIC-TYPE. Note that in some
241 ;;; cases, despite the name, we return *EMPTY-TYPE* instead of a
243 (defun make-numeric-type (&key class format (complexp :real) low high
245 ;; if interval is empty
248 (if (or (consp low) (consp high)) ; if either bound is exclusive
249 (>= (type-bound-number low) (type-bound-number high))
252 (multiple-value-bind (canonical-low canonical-high)
255 ;; INTEGER types always have their LOW and HIGH bounds
256 ;; represented as inclusive, not exclusive values.
257 (values (if (consp low)
258 (1+ (type-bound-number low))
261 (1- (type-bound-number high))
263 #!+negative-zero-is-not-zero
265 ;; Canonicalize a low bound of (-0.0) to 0.0, and a high
266 ;; bound of (+0.0) to -0.0.
267 (values (if (and (consp low)
270 (minusp (float-sign (car low))))
271 (float 0.0 (car low))
273 (if (and (consp high)
276 (plusp (float-sign (car high))))
277 (float -0.0 (car high))
280 ;; no canonicalization necessary
282 (when (and (eq class 'rational)
283 (integerp canonical-low)
284 (integerp canonical-high)
285 (= canonical-low canonical-high))
286 (setf class 'integer))
287 (%make-numeric-type :class class
292 :enumerable enumerable))))
294 (defun modified-numeric-type (base
296 (class (numeric-type-class base))
297 (format (numeric-type-format base))
298 (complexp (numeric-type-complexp base))
299 (low (numeric-type-low base))
300 (high (numeric-type-high base))
301 (enumerable (numeric-type-enumerable base)))
302 (make-numeric-type :class class
307 :enumerable enumerable))
309 ;;; An ARRAY-TYPE is used to represent any array type, including
310 ;;; things such as SIMPLE-STRING.
311 (defstruct (array-type (:include ctype
312 (class-info (type-class-or-lose 'array)))
313 (:constructor %make-array-type)
315 ;; the dimensions of the array, or * if unspecified. If a dimension
316 ;; is unspecified, it is *.
317 (dimensions '* :type (or list (member *)))
318 ;; Is this not a simple array type? (:MAYBE means that we don't know.)
319 (complexp :maybe :type (member t nil :maybe))
320 ;; the element type as originally specified
321 (element-type (missing-arg) :type ctype)
322 ;; the element type as it is specialized in this implementation
323 (specialized-element-type *wild-type* :type ctype))
324 (define-cached-synonym make-array-type)
326 ;;; A MEMBER-TYPE represent a use of the MEMBER type specifier. We
327 ;;; bother with this at this level because MEMBER types are fairly
328 ;;; important and union and intersection are well defined.
329 (defstruct (member-type (:include ctype
330 (class-info (type-class-or-lose 'member))
333 (:constructor %make-member-type (members))
334 #-sb-xc-host (:pure nil))
335 ;; the things in the set, with no duplications
336 (members nil :type list))
337 (defun make-member-type (&key members)
338 (declare (type list members))
339 ;; make sure that we've removed duplicates
340 (aver (= (length members) (length (remove-duplicates members))))
341 ;; if we have a pair of zeros (e.g. 0.0d0 and -0.0d0), then we can
342 ;; canonicalize to (DOUBLE-FLOAT 0.0d0 0.0d0), because numeric
343 ;; ranges are compared by arithmetic operators (while MEMBERship is
344 ;; compared by EQL). -- CSR, 2003-04-23
345 (let ((singlep (subsetp '(-0.0f0 0.0f0) members))
346 (doublep (subsetp '(-0.0d0 0.0d0) members))
348 (longp (subsetp '(-0.0l0 0.0l0) members)))
349 (if (or singlep doublep #!+long-float longp)
352 (push (ctype-of 0.0f0) union-types)
353 (setf members (set-difference members '(-0.0f0 0.0f0))))
355 (push (ctype-of 0.0d0) union-types)
356 (setf members (set-difference members '(-0.0d0 0.0d0))))
359 (push (ctype-of 0.0l0) union-types)
360 (setf members (set-difference members '(-0.0l0 0.0l0))))
361 (aver (not (null union-types)))
365 (cons (%make-member-type members)
367 (%make-member-type members))))
369 ;;; A COMPOUND-TYPE is a type defined out of a set of types, the
370 ;;; common parent of UNION-TYPE and INTERSECTION-TYPE.
371 (defstruct (compound-type (:include ctype
372 (might-contain-other-types-p t))
375 (types nil :type list :read-only t))
377 ;;; A UNION-TYPE represents a use of the OR type specifier which we
378 ;;; couldn't canonicalize to something simpler. Canonical form:
379 ;;; 1. All possible pairwise simplifications (using the UNION2 type
380 ;;; methods) have been performed. Thus e.g. there is never more
381 ;;; than one MEMBER-TYPE component. FIXME: As of sbcl-0.6.11.13,
382 ;;; this hadn't been fully implemented yet.
383 ;;; 2. There are never any UNION-TYPE components.
384 (defstruct (union-type (:include compound-type
385 (class-info (type-class-or-lose 'union)))
386 (:constructor %make-union-type (enumerable types))
388 (define-cached-synonym make-union-type)
390 ;;; An INTERSECTION-TYPE represents a use of the AND type specifier
391 ;;; which we couldn't canonicalize to something simpler. Canonical form:
392 ;;; 1. All possible pairwise simplifications (using the INTERSECTION2
393 ;;; type methods) have been performed. Thus e.g. there is never more
394 ;;; than one MEMBER-TYPE component.
395 ;;; 2. There are never any INTERSECTION-TYPE components: we've
396 ;;; flattened everything into a single INTERSECTION-TYPE object.
397 ;;; 3. There are never any UNION-TYPE components. Either we should
398 ;;; use the distributive rule to rearrange things so that
399 ;;; unions contain intersections and not vice versa, or we
400 ;;; should just punt to using a HAIRY-TYPE.
401 (defstruct (intersection-type (:include compound-type
402 (class-info (type-class-or-lose
404 (:constructor %make-intersection-type
408 ;;; Return TYPE converted to canonical form for a situation where the
409 ;;; "type" '* (which SBCL still represents as a type even though ANSI
410 ;;; CL defines it as a related but different kind of placeholder) is
411 ;;; equivalent to type T.
412 (defun type-*-to-t (type)
413 (if (type= type *wild-type*)
417 ;;; A CONS-TYPE is used to represent a CONS type.
418 (defstruct (cons-type (:include ctype (class-info (type-class-or-lose 'cons)))
420 ;; ANSI says that for CAR and CDR subtype
421 ;; specifiers '* is equivalent to T. In order
422 ;; to avoid special cases in SUBTYPEP and
423 ;; possibly elsewhere, we slam all CONS-TYPE
424 ;; objects into canonical form w.r.t. this
425 ;; equivalence at creation time.
426 %make-cons-type (car-raw-type
429 (car-type (type-*-to-t car-raw-type))
430 (cdr-type (type-*-to-t cdr-raw-type))))
432 ;; the CAR and CDR element types (to support ANSI (CONS FOO BAR) types)
434 ;; FIXME: Most or all other type structure slots could also be :READ-ONLY.
435 (car-type (missing-arg) :type ctype :read-only t)
436 (cdr-type (missing-arg) :type ctype :read-only t))
437 (defun make-cons-type (car-type cdr-type)
438 (if (or (eq car-type *empty-type*)
439 (eq cdr-type *empty-type*))
441 (%make-cons-type car-type cdr-type)))
445 ;;; Return the type structure corresponding to a type specifier. We
446 ;;; pick off structure types as a special case.
448 ;;; Note: VALUES-SPECIFIER-TYPE-CACHE-CLEAR must be called whenever a
449 ;;; type is defined (or redefined).
450 (defun-cached (values-specifier-type
451 :hash-function (lambda (x)
452 (logand (sxhash x) #x3FF))
454 :init-wrapper !cold-init-forms)
455 ((orig equal-but-no-car-recursion))
456 (let ((u (uncross orig)))
457 (or (info :type :builtin u)
458 (let ((spec (type-expand u)))
460 ((and (not (eq spec u))
461 (info :type :builtin spec)))
462 ((eq (info :type :kind spec) :instance)
463 (find-classoid spec))
464 ((typep spec 'classoid)
465 ;; There doesn't seem to be any way to translate
466 ;; (TYPEP SPEC 'BUILT-IN-CLASS) into something which can be
467 ;; executed on the host Common Lisp at cross-compilation time.
469 "stub: (TYPEP SPEC 'BUILT-IN-CLASS) on xc host")
470 (if (typep spec 'built-in-classoid)
471 (or (built-in-classoid-translation spec) spec)
474 (let* (;; FIXME: This automatic promotion of FOO-style
475 ;; specs to (FOO)-style specs violates the ANSI
476 ;; standard. Unfortunately, we can't fix the
477 ;; problem just by removing it, since then things
478 ;; downstream should break. But at some point we
479 ;; should fix this and the things downstream too.
480 (lspec (if (atom spec) (list spec) spec))
481 (fun (info :type :translator (car lspec))))
484 ((or (and (consp spec) (symbolp (car spec)))
486 (when (and *type-system-initialized*
487 (not (eq (info :type :kind spec)
488 :forthcoming-defclass-type)))
489 (signal 'parse-unknown-type :specifier spec))
490 ;; (The RETURN-FROM here inhibits caching.)
491 (return-from values-specifier-type
492 (make-unknown-type :specifier spec)))
494 (error "bad thing to be a type specifier: ~S"
497 ;;; This is like VALUES-SPECIFIER-TYPE, except that we guarantee to
498 ;;; never return a VALUES type.
499 (defun specifier-type (x)
500 (let ((res (values-specifier-type x)))
501 (when (values-type-p res)
502 (error "VALUES type illegal in this context:~% ~S" x))
505 (defun single-value-specifier-type (x)
506 (let ((res (specifier-type x)))
507 (if (eq res *wild-type*)
511 ;;; Similar to MACROEXPAND, but expands DEFTYPEs. We don't bother
512 ;;; returning a second value.
513 (defun type-expand (form)
514 (let ((def (cond ((symbolp form)
515 (info :type :expander form))
516 ((and (consp form) (symbolp (car form)))
517 (info :type :expander (car form)))
520 (type-expand (funcall def (if (consp form) form (list form))))
523 ;;; Note that the type NAME has been (re)defined, updating the
524 ;;; undefined warnings and VALUES-SPECIFIER-TYPE cache.
525 (defun %note-type-defined (name)
526 (declare (symbol name))
527 (note-name-defined name :type)
528 (when (boundp 'sb!kernel::*values-specifier-type-cache-vector*)
529 (values-specifier-type-cache-clear))
532 (!defun-from-collected-cold-init-forms !early-type-cold-init)