-;;;; This file contains definitions and declarations for the
-;;;; EXTENSIONS package which must be available at early cross-compile
-;;;; time, and perhaps also some things which might as well be built
-;;;; at cross-compile time even if they're not strictly needed, since
-;;;; that's harmless. Things which can't be built at cross-compile
-;;;; time (e.g. because they need machinery which only exists inside
-;;;; CMU CL's implementation of the LISP package) do not belong in
-;;;; this file.
+;;;; various extensions (including SB-INT "internal extensions")
+;;;; available both in the cross-compilation host Lisp and in the
+;;;; target SBCL
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
-(in-package "SB!EXT")
+(in-package "SB!IMPL")
-(file-comment
- "$Header$")
+;;; something not EQ to anything we might legitimately READ
+(defparameter *eof-object* (make-symbol "EOF-OBJECT"))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (defconstant max-hash sb!xc:most-positive-fixnum))
+
+(def!type hash ()
+ `(integer 0 ,max-hash))
+
+;;; a type used for indexing into arrays, and for related quantities
+;;; like lengths of lists
+;;;
+;;; It's intentionally limited to one less than the
+;;; ARRAY-DIMENSION-LIMIT for efficiency reasons, because in SBCL
+;;; ARRAY-DIMENSION-LIMIT is MOST-POSITIVE-FIXNUM, and staying below
+;;; that lets the system know it can increment a value of this type
+;;; without having to worry about using a bignum to represent the
+;;; result.
+;;;
+;;; (It should be safe to use ARRAY-DIMENSION-LIMIT as an exclusive
+;;; bound because ANSI specifies it as an exclusive bound.)
+(def!type index () `(integer 0 (,sb!xc:array-dimension-limit)))
+
+;;; like INDEX, but only up to half the maximum. Used by hash-table
+;;; code that does plenty to (aref v (* 2 i)) and (aref v (1+ (* 2 i))).
+(def!type index/2 () `(integer 0 (,(floor sb!xc:array-dimension-limit 2))))
+
+;;; like INDEX, but augmented with -1 (useful when using the index
+;;; to count downwards to 0, e.g. LOOP FOR I FROM N DOWNTO 0, with
+;;; an implementation which terminates the loop by testing for the
+;;; index leaving the loop range)
+(def!type index-or-minus-1 () `(integer -1 (,sb!xc:array-dimension-limit)))
+
+;;; A couple of VM-related types that are currently used only on the
+;;; alpha platform. -- CSR, 2002-06-24
+(def!type unsigned-byte-with-a-bite-out (s bite)
+ (cond ((eq s '*) 'integer)
+ ((and (integerp s) (> s 0))
+ (let ((bound (ash 1 s)))
+ `(integer 0 ,(- bound bite 1))))
+ (t
+ (error "Bad size specified for UNSIGNED-BYTE type specifier: ~S." s))))
+
+;;; Motivated by the mips port. -- CSR, 2002-08-22
+(def!type signed-byte-with-a-bite-out (s bite)
+ (cond ((eq s '*) 'integer)
+ ((and (integerp s) (> s 1))
+ (let ((bound (ash 1 (1- s))))
+ `(integer ,(- bound) ,(- bound bite 1))))
+ (t
+ (error "Bad size specified for SIGNED-BYTE type specifier: ~S." s))))
+
+(def!type load/store-index (scale lowtag min-offset
+ &optional (max-offset min-offset))
+ `(integer ,(- (truncate (+ (ash 1 16)
+ (* min-offset sb!vm:n-word-bytes)
+ (- lowtag))
+ scale))
+ ,(truncate (- (+ (1- (ash 1 16)) lowtag)
+ (* max-offset sb!vm:n-word-bytes))
+ scale)))
+
+#!+(or x86 x86-64)
+(defun displacement-bounds (lowtag element-size data-offset)
+ (let* ((adjustment (- (* data-offset sb!vm:n-word-bytes) lowtag))
+ (bytes-per-element (ceiling element-size sb!vm:n-byte-bits))
+ (min (truncate (+ sb!vm::minimum-immediate-offset adjustment)
+ bytes-per-element))
+ (max (truncate (+ sb!vm::maximum-immediate-offset adjustment)
+ bytes-per-element)))
+ (values min max)))
+
+#!+(or x86 x86-64)
+(def!type constant-displacement (lowtag element-size data-offset)
+ (flet ((integerify (x)
+ (etypecase x
+ (integer x)
+ (symbol (symbol-value x)))))
+ (let ((lowtag (integerify lowtag))
+ (element-size (integerify element-size))
+ (data-offset (integerify data-offset)))
+ (multiple-value-bind (min max) (displacement-bounds lowtag
+ element-size
+ data-offset)
+ `(integer ,min ,max)))))
+
+;;; Similar to FUNCTION, but the result type is "exactly" specified:
+;;; if it is an object type, then the function returns exactly one
+;;; value, if it is a short form of VALUES, then this short form
+;;; specifies the exact number of values.
+(def!type sfunction (args &optional result)
+ (let ((result (cond ((eq result '*) '*)
+ ((or (atom result)
+ (not (eq (car result) 'values)))
+ `(values ,result &optional))
+ ((intersection (cdr result) sb!xc:lambda-list-keywords)
+ result)
+ (t `(values ,@(cdr result) &optional)))))
+ `(function ,args ,result)))
+
+;;; a type specifier
+;;;
+;;; FIXME: The SB!KERNEL:INSTANCE here really means CL:CLASS.
+;;; However, the CL:CLASS type is only defined once PCL is loaded,
+;;; which is before this is evaluated. Once PCL is moved into cold
+;;; init, this might be fixable.
+(def!type type-specifier () '(or list symbol sb!kernel:instance))
;;; the default value used for initializing character data. The ANSI
-;;; spec says this is arbitrary. CMU CL used #\NULL, which we avoid
-;;; because it's not in the ANSI table of portable characters.
-(defconstant default-init-char #\space)
+;;; spec says this is arbitrary, so we use the value that falls
+;;; through when we just let the low-level consing code initialize
+;;; all newly-allocated memory to zero.
+;;;
+;;; KLUDGE: It might be nice to use something which is a
+;;; STANDARD-CHAR, both to reduce user surprise a little and, probably
+;;; more significantly, to help SBCL's cross-compiler (which knows how
+;;; to dump STANDARD-CHARs). Unfortunately, the old CMU CL code is
+;;; shot through with implicit assumptions that it's #\NULL, and code
+;;; in several places (notably both DEFUN MAKE-ARRAY and DEFTRANSFORM
+;;; MAKE-ARRAY) would have to be rewritten. -- WHN 2001-10-04
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ ;; an expression we can use to construct a DEFAULT-INIT-CHAR value
+ ;; at load time (so that we don't need to teach the cross-compiler
+ ;; how to represent and dump non-STANDARD-CHARs like #\NULL)
+ (defparameter *default-init-char-form* '(code-char 0)))
;;; CHAR-CODE values for ASCII characters which we care about but
;;; which aren't defined in section "2.1.3 Standard Characters" of the
;;; if so, perhaps implement a DEFTRANSFORM or something to stop it.
;;; (or just find a nicer way of expressing characters portably?) --
;;; WHN 19990713
-(defconstant bell-char-code 7)
-(defconstant tab-char-code 9)
-(defconstant form-feed-char-code 12)
-(defconstant return-char-code 13)
-(defconstant escape-char-code 27)
-(defconstant rubout-char-code 127)
-\f
-;;; Concatenate together the names of some strings and symbols,
-;;; producing a symbol in the current package.
-(eval-when (:compile-toplevel :load-toplevel :execute)
- (declaim (ftype (function (&rest (or string symbol)) symbol) symbolicate))
- (defun symbolicate (&rest things)
- (values (intern (apply #'concatenate
- 'string
- (mapcar #'string things))))))
-
-;;; like SYMBOLICATE, but producing keywords
-(defun keywordicate (&rest things)
- (let ((*package* *keyword-package*))
- (apply #'symbolicate things)))
+(def!constant bell-char-code 7)
+(def!constant backspace-char-code 8)
+(def!constant tab-char-code 9)
+(def!constant line-feed-char-code 10)
+(def!constant form-feed-char-code 12)
+(def!constant return-char-code 13)
+(def!constant escape-char-code 27)
+(def!constant rubout-char-code 127)
\f
-;;;; miscellaneous iteration extensions
+;;;; type-ish predicates
-(defmacro dovector ((elt vector &optional result) &rest forms)
- #!+sb-doc
- "just like DOLIST, but with one-dimensional arrays"
- (let ((index (gensym))
- (length (gensym))
- (vec (gensym)))
- `(let ((,vec ,vector))
- (declare (type vector ,vec))
- (do ((,index 0 (1+ ,index))
- (,length (length ,vec)))
- ((>= ,index ,length) ,result)
- (let ((,elt (aref ,vec ,index)))
- ,@forms)))))
-
-(defmacro dohash ((key-var value-var table &optional result) &body body)
- #!+sb-doc
- "DOHASH (Key-Var Value-Var Table [Result]) Declaration* Form*
- Iterate over the entries in a hash-table."
- (multiple-value-bind (forms decls) (parse-body body nil)
- (let ((gen (gensym))
- (n-more (gensym)))
- `(with-hash-table-iterator (,gen ,table)
- (loop
- (multiple-value-bind (,n-more ,key-var ,value-var) (,gen)
- ,@decls
- (unless ,n-more (return ,result))
- ,@forms))))))
+;;; X may contain cycles -- a conservative approximation. This
+;;; occupies a somewhat uncomfortable niche between being fast for
+;;; common cases (we don't want to allocate a hash-table), and not
+;;; falling down to exponential behaviour for large trees (so we set
+;;; an arbitrady depth limit beyond which we punt).
+(defun maybe-cyclic-p (x &optional (depth-limit 12))
+ (and (listp x)
+ (labels ((safe-cddr (cons)
+ (let ((cdr (cdr cons)))
+ (when (consp cdr)
+ (cdr cdr))))
+ (check-cycle (object seen depth)
+ (when (and (consp object)
+ (or (> depth depth-limit)
+ (member object seen)
+ (circularp object seen depth)))
+ (return-from maybe-cyclic-p t)))
+ (circularp (list seen depth)
+ ;; Almost regular circular list detection, with a twist:
+ ;; we also check each element of the list for upward
+ ;; references using CHECK-CYCLE.
+ (do ((fast (cons (car list) (cdr list)) (safe-cddr fast))
+ (slow list (cdr slow)))
+ ((not (consp fast))
+ ;; Not CDR-circular, need to check remaining CARs yet
+ (do ((tail slow (and (cdr tail))))
+ ((not (consp tail))
+ nil)
+ (check-cycle (car tail) (cons tail seen) (1+ depth))))
+ (check-cycle (car slow) (cons slow seen) (1+ depth))
+ (when (eq fast slow)
+ (return t)))))
+ (circularp x (list x) 0))))
+
+;;; Is X a (possibly-improper) list of at least N elements?
+(declaim (ftype (function (t index)) list-of-length-at-least-p))
+(defun list-of-length-at-least-p (x n)
+ (or (zerop n) ; since anything can be considered an improper list of length 0
+ (and (consp x)
+ (list-of-length-at-least-p (cdr x) (1- n)))))
+
+(declaim (inline singleton-p))
+(defun singleton-p (list)
+ (and (consp list)
+ (null (rest list))))
+
+;;; Is X is a positive prime integer?
+(defun positive-primep (x)
+ ;; This happens to be called only from one place in sbcl-0.7.0, and
+ ;; only for fixnums, we can limit it to fixnums for efficiency. (And
+ ;; if we didn't limit it to fixnums, we should use a cleverer
+ ;; algorithm, since this one scales pretty badly for huge X.)
+ (declare (fixnum x))
+ (if (<= x 5)
+ (and (>= x 2) (/= x 4))
+ (and (not (evenp x))
+ (not (zerop (rem x 3)))
+ (do ((q 6)
+ (r 1)
+ (inc 2 (logxor inc 6)) ;; 2,4,2,4...
+ (d 5 (+ d inc)))
+ ((or (= r 0) (> d q)) (/= r 0))
+ (declare (fixnum inc))
+ (multiple-value-setq (q r) (truncate x d))))))
+
+;;; Could this object contain other objects? (This is important to
+;;; the implementation of things like *PRINT-CIRCLE* and the dumper.)
+(defun compound-object-p (x)
+ (or (consp x)
+ (%instancep x)
+ (typep x '(array t *))))
\f
-;;;; hash cache utility
+;;;; the COLLECT macro
+;;;;
+;;;; comment from CMU CL: "the ultimate collection macro..."
-(eval-when (:compile-toplevel :load-toplevel :execute)
- (defvar *profile-hash-cache* nil))
+;;; helper functions for COLLECT, which become the expanders of the
+;;; MACROLET definitions created by COLLECT
+;;;
+;;; COLLECT-NORMAL-EXPANDER handles normal collection macros.
+;;;
+;;; COLLECT-LIST-EXPANDER handles the list collection case. N-TAIL
+;;; is the pointer to the current tail of the list, or NIL if the list
+;;; is empty.
+(eval-when (#-sb-xc :compile-toplevel :load-toplevel :execute)
+ (defun collect-normal-expander (n-value fun forms)
+ `(progn
+ ,@(mapcar (lambda (form) `(setq ,n-value (,fun ,form ,n-value))) forms)
+ ,n-value))
+ (defun collect-list-expander (n-value n-tail forms)
+ (let ((n-res (gensym)))
+ `(progn
+ ,@(mapcar (lambda (form)
+ `(let ((,n-res (cons ,form nil)))
+ (cond (,n-tail
+ (setf (cdr ,n-tail) ,n-res)
+ (setq ,n-tail ,n-res))
+ (t
+ (setq ,n-tail ,n-res ,n-value ,n-res)))))
+ forms)
+ ,n-value))))
-;;; :INIT-WRAPPER is set to COLD-INIT-FORMS in type system definitions
-;;; so that caches will be created before top-level forms run.
-(defmacro define-hash-cache (name args &key hash-function hash-bits default
- (init-wrapper 'progn)
- (values 1))
+;;; Collect some values somehow. Each of the collections specifies a
+;;; bunch of things which collected during the evaluation of the body
+;;; of the form. The name of the collection is used to define a local
+;;; macro, a la MACROLET. Within the body, this macro will evaluate
+;;; each of its arguments and collect the result, returning the
+;;; current value after the collection is done. The body is evaluated
+;;; as a PROGN; to get the final values when you are done, just call
+;;; the collection macro with no arguments.
+;;;
+;;; INITIAL-VALUE is the value that the collection starts out with,
+;;; which defaults to NIL. FUNCTION is the function which does the
+;;; collection. It is a function which will accept two arguments: the
+;;; value to be collected and the current collection. The result of
+;;; the function is made the new value for the collection. As a
+;;; totally magical special-case, FUNCTION may be COLLECT, which tells
+;;; us to build a list in forward order; this is the default. If an
+;;; INITIAL-VALUE is supplied for COLLECT, the stuff will be RPLACD'd
+;;; onto the end. Note that FUNCTION may be anything that can appear
+;;; in the functional position, including macros and lambdas.
+(defmacro collect (collections &body body)
+ (let ((macros ())
+ (binds ()))
+ (dolist (spec collections)
+ (unless (proper-list-of-length-p spec 1 3)
+ (error "malformed collection specifier: ~S" spec))
+ (let* ((name (first spec))
+ (default (second spec))
+ (kind (or (third spec) 'collect))
+ (n-value (gensym (concatenate 'string
+ (symbol-name name)
+ "-N-VALUE-"))))
+ (push `(,n-value ,default) binds)
+ (if (eq kind 'collect)
+ (let ((n-tail (gensym (concatenate 'string
+ (symbol-name name)
+ "-N-TAIL-"))))
+ (if default
+ (push `(,n-tail (last ,n-value)) binds)
+ (push n-tail binds))
+ (push `(,name (&rest args)
+ (collect-list-expander ',n-value ',n-tail args))
+ macros))
+ (push `(,name (&rest args)
+ (collect-normal-expander ',n-value ',kind args))
+ macros))))
+ `(macrolet ,macros (let* ,(nreverse binds) ,@body))))
+\f
+;;;; some old-fashioned functions. (They're not just for old-fashioned
+;;;; code, they're also used as optimized forms of the corresponding
+;;;; general functions when the compiler can prove that they're
+;;;; equivalent.)
+
+;;; like (MEMBER ITEM LIST :TEST #'EQ)
+(defun memq (item list)
#!+sb-doc
- "DEFINE-HASH-CACHE Name ({(Arg-Name Test-Function)}*) {Key Value}*
- Define a hash cache that associates some number of argument values to a
- result value. The Test-Function paired with each Arg-Name is used to compare
- the value for that arg in a cache entry with a supplied arg. The
- Test-Function must not error when passed NIL as its first arg, but need not
- return any particular value. Test-Function may be any thing that can be
- placed in CAR position.
+ "Return tail of LIST beginning with first element EQ to ITEM."
+ ;; KLUDGE: These could be and probably should be defined as
+ ;; (MEMBER ITEM LIST :TEST #'EQ)),
+ ;; but when I try to cross-compile that, I get an error from
+ ;; LTN-ANALYZE-KNOWN-CALL, "Recursive known function definition". The
+ ;; comments for that error say it "is probably a botched interpreter stub".
+ ;; Rather than try to figure that out, I just rewrote this function from
+ ;; scratch. -- WHN 19990512
+ (do ((i list (cdr i)))
+ ((null i))
+ (when (eq (car i) item)
+ (return i))))
- Name is used to define these functions:
+;;; like (ASSOC ITEM ALIST :TEST #'EQ):
+;;; Return the first pair of ALIST where ITEM is EQ to the key of
+;;; the pair.
+(defun assq (item alist)
+ ;; KLUDGE: CMU CL defined this with
+ ;; (DECLARE (INLINE ASSOC))
+ ;; (ASSOC ITEM ALIST :TEST #'EQ))
+ ;; which is pretty, but which would have required adding awkward
+ ;; build order constraints on SBCL (or figuring out some way to make
+ ;; inline definitions installable at build-the-cross-compiler time,
+ ;; which was too ambitious for now). Rather than mess with that, we
+ ;; just define ASSQ explicitly in terms of more primitive
+ ;; operations:
+ (dolist (pair alist)
+ ;; though it may look more natural to write this as
+ ;; (AND PAIR (EQ (CAR PAIR) ITEM))
+ ;; the temptation to do so should be resisted, as pointed out by PFD
+ ;; sbcl-devel 2003-08-16, as NIL elements are rare in association
+ ;; lists. -- CSR, 2003-08-16
+ (when (and (eq (car pair) item) (not (null pair)))
+ (return pair))))
- <name>-CACHE-LOOKUP Arg*
- See whether there is an entry for the specified Args in the cache. If
- not present, the :DEFAULT keyword (default NIL) determines the result(s).
+;;; like (DELETE .. :TEST #'EQ):
+;;; Delete all LIST entries EQ to ITEM (destructively modifying
+;;; LIST), and return the modified LIST.
+(defun delq (item list)
+ (let ((list list))
+ (do ((x list (cdr x))
+ (splice '()))
+ ((endp x) list)
+ (cond ((eq item (car x))
+ (if (null splice)
+ (setq list (cdr x))
+ (rplacd splice (cdr x))))
+ (t (setq splice x)))))) ; Move splice along to include element.
- <name>-CACHE-ENTER Arg* Value*
- Encache the association of the specified args with Value.
- <name>-CACHE-CLEAR
- Reinitialize the cache, invalidating all entries and allowing the
- arguments and result values to be GC'd.
+;;; like (POSITION .. :TEST #'EQ):
+;;; Return the position of the first element EQ to ITEM.
+(defun posq (item list)
+ (do ((i list (cdr i))
+ (j 0 (1+ j)))
+ ((null i))
+ (when (eq (car i) item)
+ (return j))))
- These other keywords are defined:
+(declaim (inline neq))
+(defun neq (x y)
+ (not (eq x y)))
- :HASH-BITS <n>
- The size of the cache as a power of 2.
+;;; not really an old-fashioned function, but what the calling
+;;; convention should've been: like NTH, but with the same argument
+;;; order as in all the other indexed dereferencing functions, with
+;;; the collection first and the index second
+(declaim (inline nth-but-with-sane-arg-order))
+(declaim (ftype (function (list index) t) nth-but-with-sane-arg-order))
+(defun nth-but-with-sane-arg-order (list index)
+ (nth index list))
- :HASH-FUNCTION function
- Some thing that can be placed in CAR position which will compute a value
- between 0 and (1- (expt 2 <hash-bits>)).
+(defun adjust-list (list length initial-element)
+ (let ((old-length (length list)))
+ (cond ((< old-length length)
+ (append list (make-list (- length old-length)
+ :initial-element initial-element)))
+ ((> old-length length)
+ (subseq list 0 length))
+ (t list))))
+\f
+;;;; miscellaneous iteration extensions
+
+;;; like Scheme's named LET
+;;;
+;;; (CMU CL called this ITERATE, and commented it as "the ultimate
+;;; iteration macro...". I (WHN) found the old name insufficiently
+;;; specific to remind me what the macro means, so I renamed it.)
+(defmacro named-let (name binds &body body)
+ (dolist (x binds)
+ (unless (proper-list-of-length-p x 2)
+ (error "malformed NAMED-LET variable spec: ~S" x)))
+ `(labels ((,name ,(mapcar #'first binds) ,@body))
+ (,name ,@(mapcar #'second binds))))
- :VALUES <n>
- The number of values cached.
+(defun filter-dolist-declarations (decls)
+ (mapcar (lambda (decl)
+ `(declare ,@(remove-if
+ (lambda (clause)
+ (and (consp clause)
+ (or (eq (car clause) 'type)
+ (eq (car clause) 'ignore))))
+ (cdr decl))))
+ decls))
- :INIT-WRAPPER <name>
- The code for initializing the cache is wrapped in a form with the
- specified name. Default PROGN."
+;;; just like DOLIST, but with one-dimensional arrays
+(defmacro dovector ((elt vector &optional result) &body body)
+ (multiple-value-bind (forms decls) (parse-body body :doc-string-allowed nil)
+ (with-unique-names (index length vec)
+ `(let ((,vec ,vector))
+ (declare (type vector ,vec))
+ (do ((,index 0 (1+ ,index))
+ (,length (length ,vec)))
+ ((>= ,index ,length) (let ((,elt nil))
+ ,@(filter-dolist-declarations decls)
+ ,elt
+ ,result))
+ (let ((,elt (aref ,vec ,index)))
+ ,@decls
+ (tagbody
+ ,@forms)))))))
- (let* ((var-name (symbolicate "*" name "-CACHE-VECTOR*"))
- (nargs (length args))
- (entry-size (+ nargs values))
- (size (ash 1 hash-bits))
- (total-size (* entry-size size))
- (default-values (if (and (consp default) (eq (car default) 'values))
- (cdr default)
- (list default)))
- (n-index (gensym))
- (n-cache (gensym)))
+;;; Iterate over the entries in a HASH-TABLE, first obtaining the lock
+;;; if the table is a synchronized table.
+(defmacro dohash (((key-var value-var) table &key result locked) &body body)
+ (multiple-value-bind (forms decls) (parse-body body :doc-string-allowed nil)
+ (with-unique-names (gen n-more n-table)
+ (let ((iter-form `(with-hash-table-iterator (,gen ,n-table)
+ (loop
+ (multiple-value-bind (,n-more ,key-var ,value-var) (,gen)
+ ,@decls
+ (unless ,n-more (return ,result))
+ ,@forms)))))
+ `(let ((,n-table ,table))
+ ,(if locked
+ `(with-locked-hash-table (,n-table)
+ ,iter-form)
+ iter-form))))))
+\f
+;;;; hash cache utility
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (defvar *profile-hash-cache* nil))
+
+;;; a flag for whether it's too early in cold init to use caches so
+;;; that we have a better chance of recovering so that we have a
+;;; better chance of getting the system running so that we have a
+;;; better chance of diagnosing the problem which caused us to use the
+;;; caches too early
+#!+sb-show
+(defvar *hash-caches-initialized-p*)
+
+;;; Define a hash cache that associates some number of argument values
+;;; with a result value. The TEST-FUNCTION paired with each ARG-NAME
+;;; is used to compare the value for that arg in a cache entry with a
+;;; supplied arg. The TEST-FUNCTION must not error when passed NIL as
+;;; its first arg, but need not return any particular value.
+;;; TEST-FUNCTION may be any thing that can be placed in CAR position.
+;;;
+;;; This code used to store all the arguments / return values directly
+;;; in the cache vector. This was both interrupt- and thread-unsafe, since
+;;; it was possible that *-CACHE-ENTER would scribble over a region of the
+;;; cache vector which *-CACHE-LOOKUP had only partially processed. Instead
+;;; we now store the contents of each cache bucket as a separate array, which
+;;; is stored in the appropriate cell in the cache vector. A new bucket array
+;;; is created every time *-CACHE-ENTER is called, and the old ones are never
+;;; modified. This means that *-CACHE-LOOKUP will always work with a set
+;;; of consistent data. The overhead caused by consing new buckets seems to
+;;; be insignificant on the grand scale of things. -- JES, 2006-11-02
+;;;
+;;; NAME is used to define these functions:
+;;; <name>-CACHE-LOOKUP Arg*
+;;; See whether there is an entry for the specified ARGs in the
+;;; cache. If not present, the :DEFAULT keyword (default NIL)
+;;; determines the result(s).
+;;; <name>-CACHE-ENTER Arg* Value*
+;;; Encache the association of the specified args with VALUE.
+;;; <name>-CACHE-CLEAR
+;;; Reinitialize the cache, invalidating all entries and allowing
+;;; the arguments and result values to be GC'd.
+;;;
+;;; These other keywords are defined:
+;;; :HASH-BITS <n>
+;;; The size of the cache as a power of 2.
+;;; :HASH-FUNCTION function
+;;; Some thing that can be placed in CAR position which will compute
+;;; a value between 0 and (1- (expt 2 <hash-bits>)).
+;;; :VALUES <n>
+;;; the number of return values cached for each function call
+;;; :INIT-WRAPPER <name>
+;;; The code for initializing the cache is wrapped in a form with
+;;; the specified name. (:INIT-WRAPPER is set to COLD-INIT-FORMS
+;;; in type system definitions so that caches will be created
+;;; before top level forms run.)
+(defmacro define-hash-cache (name args &key hash-function hash-bits default
+ (init-wrapper 'progn)
+ (values 1))
+ (let* ((var-name (symbolicate "*" name "-CACHE-VECTOR*"))
+ (probes-name (when *profile-hash-cache*
+ (symbolicate "*" name "-CACHE-PROBES*")))
+ (misses-name (when *profile-hash-cache*
+ (symbolicate "*" name "-CACHE-MISSES*")))
+ (nargs (length args))
+ (size (ash 1 hash-bits))
+ (default-values (if (and (consp default) (eq (car default) 'values))
+ (cdr default)
+ (list default)))
+ (args-and-values (sb!xc:gensym "ARGS-AND-VALUES"))
+ (args-and-values-size (+ nargs values))
+ (n-index (sb!xc:gensym "INDEX"))
+ (n-cache (sb!xc:gensym "CACHE")))
+ (declare (ignorable probes-name misses-name))
(unless (= (length default-values) values)
- (error "The number of default values ~S differs from :VALUES ~D."
- default values))
+ (error "The number of default values ~S differs from :VALUES ~W."
+ default values))
(collect ((inlines)
- (forms)
- (inits)
- (tests)
- (sets)
- (arg-vars)
- (values-indices)
- (values-names))
+ (forms)
+ (inits)
+ (sets)
+ (tests)
+ (arg-vars)
+ (values-refs)
+ (values-names))
(dotimes (i values)
- (values-indices `(+ ,n-index ,(+ nargs i)))
- (values-names (gensym)))
+ (let ((name (sb!xc:gensym "VALUE")))
+ (values-names name)
+ (values-refs `(svref ,args-and-values (+ ,nargs ,i)))
+ (sets `(setf (svref ,args-and-values (+ ,nargs ,i)) ,name))))
(let ((n 0))
(dolist (arg args)
(unless (= (length arg) 2)
- (error "bad arg spec: ~S" arg))
+ (error "bad argument spec: ~S" arg))
(let ((arg-name (first arg))
(test (second arg)))
(arg-vars arg-name)
- (tests `(,test (svref ,n-cache (+ ,n-index ,n)) ,arg-name))
- (sets `(setf (svref ,n-cache (+ ,n-index ,n)) ,arg-name)))
+ (tests `(,test (svref ,args-and-values ,n) ,arg-name))
+ (sets `(setf (svref ,args-and-values ,n) ,arg-name)))
(incf n)))
(when *profile-hash-cache*
- (let ((n-probe (symbolicate "*" name "-CACHE-PROBES*"))
- (n-miss (symbolicate "*" name "-CACHE-MISSES*")))
- (inits `(setq ,n-probe 0))
- (inits `(setq ,n-miss 0))
- (forms `(defvar ,n-probe))
- (forms `(defvar ,n-miss))
- (forms `(declaim (fixnum ,n-miss ,n-probe)))))
+ (inits `(setq ,probes-name 0))
+ (inits `(setq ,misses-name 0))
+ (forms `(declaim (fixnum ,probes-name ,misses-name))))
(let ((fun-name (symbolicate name "-CACHE-LOOKUP")))
- (inlines fun-name)
- (forms
- `(defun ,fun-name ,(arg-vars)
- ,@(when *profile-hash-cache*
- `((incf ,(symbolicate "*" name "-CACHE-PROBES*"))))
- (let ((,n-index (* (,hash-function ,@(arg-vars)) ,entry-size))
- (,n-cache ,var-name))
- (declare (type fixnum ,n-index))
- (cond ((and ,@(tests))
- (values ,@(mapcar (lambda (x) `(svref ,n-cache ,x))
- (values-indices))))
- (t
- ,@(when *profile-hash-cache*
- `((incf ,(symbolicate "*" name "-CACHE-MISSES*"))))
- ,default))))))
+ (inlines fun-name)
+ (forms
+ `(defun ,fun-name ,(arg-vars)
+ ,@(when *profile-hash-cache*
+ `((incf ,probes-name)))
+ (let* ((,n-index (,hash-function ,@(arg-vars)))
+ (,n-cache ,var-name)
+ (,args-and-values (svref ,n-cache ,n-index)))
+ (cond ((and ,args-and-values
+ ,@(tests))
+ (values ,@(values-refs)))
+ (t
+ ,@(when *profile-hash-cache*
+ `((incf ,misses-name)))
+ ,default))))))
(let ((fun-name (symbolicate name "-CACHE-ENTER")))
- (inlines fun-name)
- (forms
- `(defun ,fun-name (,@(arg-vars) ,@(values-names))
- (let ((,n-index (* (,hash-function ,@(arg-vars)) ,entry-size))
- (,n-cache ,var-name))
- (declare (type fixnum ,n-index))
- ,@(sets)
- ,@(mapcar #'(lambda (i val)
- `(setf (svref ,n-cache ,i) ,val))
- (values-indices)
- (values-names))
- (values)))))
+ (inlines fun-name)
+ (forms
+ `(defun ,fun-name (,@(arg-vars) ,@(values-names))
+ (let ((,n-index (,hash-function ,@(arg-vars)))
+ (,n-cache ,var-name)
+ (,args-and-values (make-array ,args-and-values-size)))
+ ,@(sets)
+ (setf (svref ,n-cache ,n-index) ,args-and-values))
+ (values))))
(let ((fun-name (symbolicate name "-CACHE-CLEAR")))
- (forms
- `(defun ,fun-name ()
- (do ((,n-index ,(- total-size entry-size) (- ,n-index ,entry-size))
- (,n-cache ,var-name))
- ((minusp ,n-index))
- (declare (type fixnum ,n-index))
- ,@(collect ((arg-sets))
- (dotimes (i nargs)
- (arg-sets `(setf (svref ,n-cache (+ ,n-index ,i)) nil)))
- (arg-sets))
- ,@(mapcar #'(lambda (i val)
- `(setf (svref ,n-cache ,i) ,val))
- (values-indices)
- default-values))
- (values)))
- (forms `(,fun-name)))
+ (forms
+ `(defun ,fun-name ()
+ (fill ,var-name nil)))
+ (forms `(,fun-name)))
(inits `(unless (boundp ',var-name)
- (setq ,var-name (make-array ,total-size))))
+ (setq ,var-name (make-array ,size :initial-element nil))))
+ #!+sb-show (inits `(setq *hash-caches-initialized-p* t))
`(progn
- (defvar ,var-name)
- (declaim (type (simple-vector ,total-size) ,var-name))
- #!-sb-fluid (declaim (inline ,@(inlines)))
- (,init-wrapper ,@(inits))
- ,@(forms)
- ',name))))
+ (defvar ,var-name)
+ ,@(when *profile-hash-cache*
+ `((defvar ,probes-name)
+ (defvar ,misses-name)))
+ (declaim (type (simple-vector ,size) ,var-name))
+ #!-sb-fluid (declaim (inline ,@(inlines)))
+ (,init-wrapper ,@(inits))
+ ,@(forms)
+ ',name))))
+;;; some syntactic sugar for defining a function whose values are
+;;; cached by DEFINE-HASH-CACHE
(defmacro defun-cached ((name &rest options &key (values 1) default
- &allow-other-keys)
- args &body body-decls-doc)
- #!+sb-doc
- "DEFUN-CACHED (Name {Key Value}*) ({(Arg-Name Test-Function)}*) Form*
- Some syntactic sugar for defining a function whose values are cached by
- DEFINE-HASH-CACHE."
+ &allow-other-keys)
+ args &body body-decls-doc)
(let ((default-values (if (and (consp default) (eq (car default) 'values))
- (cdr default)
- (list default)))
- (arg-names (mapcar #'car args)))
- (collect ((values-names))
- (dotimes (i values)
- (values-names (gensym)))
- (multiple-value-bind (body decls doc) (parse-body body-decls-doc)
- `(progn
- (define-hash-cache ,name ,args ,@options)
- (defun ,name ,arg-names
- ,@decls
- ,doc
- (multiple-value-bind ,(values-names)
- (,(symbolicate name "-CACHE-LOOKUP") ,@arg-names)
- (if (and ,@(mapcar #'(lambda (val def)
- `(eq ,val ,def))
- (values-names) default-values))
- (multiple-value-bind ,(values-names)
- (progn ,@body)
- (,(symbolicate name "-CACHE-ENTER") ,@arg-names
- ,@(values-names))
- (values ,@(values-names)))
- (values ,@(values-names))))))))))
+ (cdr default)
+ (list default)))
+ (arg-names (mapcar #'car args))
+ (values-names (make-gensym-list values)))
+ (multiple-value-bind (body decls doc) (parse-body body-decls-doc)
+ `(progn
+ (define-hash-cache ,name ,args ,@options)
+ (defun ,name ,arg-names
+ ,@decls
+ ,doc
+ (cond #!+sb-show
+ ((not (boundp '*hash-caches-initialized-p*))
+ ;; This shouldn't happen, but it did happen to me
+ ;; when revising the type system, and it's a lot
+ ;; easier to figure out what what's going on with
+ ;; that kind of problem if the system can be kept
+ ;; alive until cold boot is complete. The recovery
+ ;; mechanism should definitely be conditional on some
+ ;; debugging feature (e.g. SB-SHOW) because it's big,
+ ;; duplicating all the BODY code. -- WHN
+ (/show0 ,name " too early in cold init, uncached")
+ (/show0 ,(first arg-names) "=..")
+ (/hexstr ,(first arg-names))
+ ,@body)
+ (t
+ (multiple-value-bind ,values-names
+ (,(symbolicate name "-CACHE-LOOKUP") ,@arg-names)
+ (if (and ,@(mapcar (lambda (val def)
+ `(eq ,val ,def))
+ values-names default-values))
+ (multiple-value-bind ,values-names
+ (progn ,@body)
+ (,(symbolicate name "-CACHE-ENTER") ,@arg-names
+ ,@values-names)
+ (values ,@values-names))
+ (values ,@values-names))))))))))
+
+(defmacro define-cached-synonym
+ (name &optional (original (symbolicate "%" name)))
+ (let ((cached-name (symbolicate "%%" name "-CACHED")))
+ `(progn
+ (defun-cached (,cached-name :hash-bits 8
+ :hash-function (lambda (x)
+ (logand (sxhash x) #xff)))
+ ((args equal))
+ (apply #',original args))
+ (defun ,name (&rest args)
+ (,cached-name args)))))
+
+;;; FIXME: maybe not the best place
+;;;
+;;; FIXME: think of a better name -- not only does this not have the
+;;; CAR recursion of EQUAL, it also doesn't have the special treatment
+;;; of pathnames, bit-vectors and strings.
+;;;
+;;; KLUDGE: This means that we will no longer cache specifiers of the
+;;; form '(INTEGER (0) 4). This is probably not a disaster.
+;;;
+;;; A helper function for the type system, which is the main user of
+;;; these caches: we must be more conservative than EQUAL for some of
+;;; our equality tests, because MEMBER and friends refer to EQLity.
+;;; So:
+(defun equal-but-no-car-recursion (x y)
+ (cond
+ ((eql x y) t)
+ ((consp x)
+ (and (consp y)
+ (eql (car x) (car y))
+ (equal-but-no-car-recursion (cdr x) (cdr y))))
+ (t nil)))
\f
;;;; package idioms
(defun %find-package-or-lose (package-designator)
(or (find-package package-designator)
(error 'sb!kernel:simple-package-error
- :package package-designator
- :format-control "The name ~S does not designate any package."
- :format-arguments (list package-designator))))
+ :package package-designator
+ :format-control "The name ~S does not designate any package."
+ :format-arguments (list package-designator))))
;;; ANSI specifies (in the section for FIND-PACKAGE) that the
;;; consequences of most operations on deleted packages are
(defun find-undeleted-package-or-lose (package-designator)
(let ((maybe-result (%find-package-or-lose package-designator)))
(if (package-name maybe-result) ; if not deleted
- maybe-result
- (error 'sb!kernel:simple-package-error
- :package maybe-result
- :format-control "The package ~S has been deleted."
- :format-arguments (list maybe-result)))))
+ maybe-result
+ (error 'sb!kernel:simple-package-error
+ :package maybe-result
+ :format-control "The package ~S has been deleted."
+ :format-arguments (list maybe-result)))))
\f
-;;;; miscellany
-
-;;; FIXME: What is this used for that SYMBOLICATE couldn't be used for instead?
-;;; If nothing, replace it.
-(eval-when (:compile-toplevel :load-toplevel :execute)
- (defun concat-pnames (name1 name2)
- (declare (symbol name1 name2))
- (if name1
- (intern (concatenate 'simple-string
- (symbol-name name1)
- (symbol-name name2)))
- name2)))
+;;;; various operations on names
;;; Is NAME a legal function name?
-(defun legal-function-name-p (name)
- (or (symbolp name)
- (and (consp name)
- (eq (car name) 'setf)
- (consp (cdr name))
- (symbolp (cadr name))
- (null (cddr name)))))
-
-;;; Given a function name, return the name for the BLOCK which encloses its
-;;; body (e.g. in DEFUN, DEFINE-COMPILER-MACRO, or FLET).
-(declaim (ftype (function ((or symbol cons)) symbol) function-name-block-name))
-(defun function-name-block-name (function-name)
- (cond ((symbolp function-name)
- function-name)
- ((and (consp function-name)
- (= (length function-name) 2)
- (eq (first function-name) 'setf))
- (second function-name))
- (t
- (error "not legal as a function name: ~S" function-name))))
+(declaim (inline legal-fun-name-p))
+(defun legal-fun-name-p (name)
+ (values (valid-function-name-p name)))
-;;; Is X a (possibly-improper) list of at least N elements?
-(defun list-of-length-at-least-p (x n)
- (declare (type (and unsigned-byte fixnum) n))
- (or (zerop n) ; since anything can be considered an improper list of length 0
- (and (consp x)
- (list-of-length-at-least-p (cdr x) (1- n)))))
+(deftype function-name () '(satisfies legal-fun-name-p))
+
+;;; Signal an error unless NAME is a legal function name.
+(defun legal-fun-name-or-type-error (name)
+ (unless (legal-fun-name-p name)
+ (error 'simple-type-error
+ :datum name
+ :expected-type 'function-name
+ :format-control "invalid function name: ~S"
+ :format-arguments (list name))))
+
+;;; Given a function name, return the symbol embedded in it.
+;;;
+;;; The ordinary use for this operator (and the motivation for the
+;;; name of this operator) is to convert from a function name to the
+;;; name of the BLOCK which encloses its body.
+;;;
+;;; Occasionally the operator is useful elsewhere, where the operator
+;;; name is less mnemonic. (Maybe it should be changed?)
+(declaim (ftype (function ((or symbol cons)) symbol) fun-name-block-name))
+(defun fun-name-block-name (fun-name)
+ (cond ((symbolp fun-name)
+ fun-name)
+ ((consp fun-name)
+ (multiple-value-bind (legalp block-name)
+ (valid-function-name-p fun-name)
+ (if legalp
+ block-name
+ (error "not legal as a function name: ~S" fun-name))))
+ (t
+ (error "not legal as a function name: ~S" fun-name))))
+
+(defun looks-like-name-of-special-var-p (x)
+ (and (symbolp x)
+ (let ((name (symbol-name x)))
+ (and (> (length name) 2) ; to exclude '* and '**
+ (char= #\* (aref name 0))
+ (char= #\* (aref name (1- (length name))))))))
+
+;;; This function is to be called just before a change which would affect the
+;;; symbol value. We don't absolutely have to call this function before such
+;;; changes, since such changes to constants are given as undefined behavior,
+;;; it's nice to do so. To circumvent this you need code like this:
+;;;
+;;; (defvar foo)
+;;; (defun set-foo (x) (setq foo x))
+;;; (defconstant foo 42)
+;;; (set-foo 13)
+;;; foo => 13, (constantp 'foo) => t
+;;;
+;;; ...in which case you frankly deserve to lose.
+(defun about-to-modify-symbol-value (symbol action &optional (new-value nil valuep) bind)
+ (declare (symbol symbol))
+ (flet ((describe-action ()
+ (ecase action
+ (set "set SYMBOL-VALUE of ~S")
+ (progv "bind ~S")
+ (compare-and-swap "compare-and-swap SYMBOL-VALUE of ~S")
+ (defconstant "define ~S as a constant")
+ (makunbound "make ~S unbound"))))
+ (let ((kind (info :variable :kind symbol)))
+ (multiple-value-bind (what continue)
+ (cond ((eq :constant kind)
+ (cond ((eq symbol t)
+ (values "Veritas aeterna. (can't ~@?)" nil))
+ ((eq symbol nil)
+ (values "Nihil ex nihil. (can't ~@?)" nil))
+ ((keywordp symbol)
+ (values "Can't ~@?." nil))
+ (t
+ (values "Constant modification: attempt to ~@?." t))))
+ ((and bind (eq :global kind))
+ (values "Can't ~@? (global variable)." nil)))
+ (when what
+ (if continue
+ (cerror "Modify the constant." what (describe-action) symbol)
+ (error what (describe-action) symbol)))
+ (when valuep
+ ;; :VARIABLE :TYPE is in the db only if it is declared, so no need to
+ ;; check.
+ (let ((type (info :variable :type symbol)))
+ (unless (sb!kernel::%%typep new-value type nil)
+ (let ((spec (type-specifier type)))
+ (error 'simple-type-error
+ :format-control "~@<Cannot ~@? to ~S, not of type ~S.~:@>"
+ :format-arguments (list (describe-action) symbol new-value spec)
+ :datum new-value
+ :expected-type spec))))))))
+ (values))
+
+;;; If COLD-FSET occurs not at top level, just treat it as an ordinary
+;;; assignment instead of doing cold static linking. That way things like
+;;; (FLET ((FROB (X) ..))
+;;; (DEFUN FOO (X Y) (FROB X) ..)
+;;; (DEFUN BAR (Z) (AND (FROB X) ..)))
+;;; can still "work" for cold init: they don't do magical static
+;;; linking the way that true toplevel DEFUNs do, but at least they do
+;;; the linking eventually, so as long as #'FOO and #'BAR aren't
+;;; needed until "cold toplevel forms" have executed, it's OK.
+(defmacro cold-fset (name lambda)
+ (style-warn
+ "~@<COLD-FSET ~S not cross-compiled at top level: demoting to ~
+(SETF FDEFINITION)~:@>"
+ name)
+ ;; We convert the LAMBDA expression to the corresponding NAMED-LAMBDA
+ ;; expression so that the compiler can use NAME in debug names etc.
+ (destructuring-bind (lambda-symbol &rest lambda-rest) lambda
+ (assert (eql lambda-symbol 'lambda)) ; else dunno how to do conversion
+ `(setf (fdefinition ',name)
+ (named-lambda ,name ,@lambda-rest))))
+\f
+;;;; ONCE-ONLY
+;;;;
+;;;; "The macro ONCE-ONLY has been around for a long time on various
+;;;; systems [..] if you can understand how to write and when to use
+;;;; ONCE-ONLY, then you truly understand macro." -- Peter Norvig,
+;;;; _Paradigms of Artificial Intelligence Programming: Case Studies
+;;;; in Common Lisp_, p. 853
+
+;;; ONCE-ONLY is a utility useful in writing source transforms and
+;;; macros. It provides a concise way to wrap a LET around some code
+;;; to ensure that some forms are only evaluated once.
+;;;
+;;; Create a LET* which evaluates each value expression, binding a
+;;; temporary variable to the result, and wrapping the LET* around the
+;;; result of the evaluation of BODY. Within the body, each VAR is
+;;; bound to the corresponding temporary variable.
+(defmacro once-only (specs &body body)
+ (named-let frob ((specs specs)
+ (body body))
+ (if (null specs)
+ `(progn ,@body)
+ (let ((spec (first specs)))
+ ;; FIXME: should just be DESTRUCTURING-BIND of SPEC
+ (unless (proper-list-of-length-p spec 2)
+ (error "malformed ONCE-ONLY binding spec: ~S" spec))
+ (let* ((name (first spec))
+ (exp-temp (gensym "ONCE-ONLY")))
+ `(let ((,exp-temp ,(second spec))
+ (,name (gensym ,(symbol-name name))))
+ `(let ((,,name ,,exp-temp))
+ ,,(frob (rest specs) body))))))))
+\f
+;;;; various error-checking utilities
+
+;;; This function can be used as the default value for keyword
+;;; arguments that must be always be supplied. Since it is known by
+;;; the compiler to never return, it will avoid any compile-time type
+;;; warnings that would result from a default value inconsistent with
+;;; the declared type. When this function is called, it signals an
+;;; error indicating that a required &KEY argument was not supplied.
+;;; This function is also useful for DEFSTRUCT slot defaults
+;;; corresponding to required arguments.
+(declaim (ftype (function () nil) missing-arg))
+(defun missing-arg ()
+ #!+sb-doc
+ (/show0 "entering MISSING-ARG")
+ (error "A required &KEY or &OPTIONAL argument was not supplied."))
+
+;;; like CL:ASSERT and CL:CHECK-TYPE, but lighter-weight
+;;;
+;;; (As of sbcl-0.6.11.20, we were using some 400 calls to CL:ASSERT.
+;;; The CL:ASSERT restarts and whatnot expand into a significant
+;;; amount of code when you multiply them by 400, so replacing them
+;;; with this should reduce the size of the system by enough to be
+;;; worthwhile. ENFORCE-TYPE is much less common, but might still be
+;;; worthwhile, and since I don't really like CERROR stuff deep in the
+;;; guts of complex systems anyway, I replaced it too.)
+(defmacro aver (expr)
+ `(unless ,expr
+ (%failed-aver ',expr)))
+
+(defun %failed-aver (expr)
+ ;; hackish way to tell we're in a cold sbcl and output the
+ ;; message before signalling error, as it may be this is too
+ ;; early in the cold init.
+ (when (find-package "SB!C")
+ (fresh-line)
+ (write-line "failed AVER:")
+ (write expr)
+ (terpri))
+ (bug "~@<failed AVER: ~2I~_~A~:>" expr))
+
+(defun bug (format-control &rest format-arguments)
+ (error 'bug
+ :format-control format-control
+ :format-arguments format-arguments))
+
+(defmacro enforce-type (value type)
+ (once-only ((value value))
+ `(unless (typep ,value ',type)
+ (%failed-enforce-type ,value ',type))))
+
+(defun %failed-enforce-type (value type)
+ ;; maybe should be TYPE-BUG, subclass of BUG? If it is changed,
+ ;; check uses of it in user-facing code (e.g. WARN)
+ (error 'simple-type-error
+ :datum value
+ :expected-type type
+ :format-control "~@<~S ~_is not a ~_~S~:>"
+ :format-arguments (list value type)))
+\f
+;;; Return a function like FUN, but expecting its (two) arguments in
+;;; the opposite order that FUN does.
+(declaim (inline swapped-args-fun))
+(defun swapped-args-fun (fun)
+ (declare (type function fun))
+ (lambda (x y)
+ (funcall fun y x)))
+
+;;; Return the numeric value of a type bound, i.e. an interval bound
+;;; more or less in the format of bounds in ANSI's type specifiers,
+;;; where a bare numeric value is a closed bound and a list of a
+;;; single numeric value is an open bound.
+;;;
+;;; The "more or less" bit is that the no-bound-at-all case is
+;;; represented by NIL (not by * as in ANSI type specifiers); and in
+;;; this case we return NIL.
+(defun type-bound-number (x)
+ (if (consp x)
+ (destructuring-bind (result) x result)
+ x))
+
+;;; some commonly-occuring CONSTANTLY forms
+(macrolet ((def-constantly-fun (name constant-expr)
+ `(setf (symbol-function ',name)
+ (constantly ,constant-expr))))
+ (def-constantly-fun constantly-t t)
+ (def-constantly-fun constantly-nil nil)
+ (def-constantly-fun constantly-0 0))
+
+;;; If X is a symbol, see whether it is present in *FEATURES*. Also
+;;; handle arbitrary combinations of atoms using NOT, AND, OR.
+(defun featurep (x)
+ (etypecase x
+ (cons
+ (case (car x)
+ ((:not not)
+ (cond
+ ((cddr x)
+ (error "too many subexpressions in feature expression: ~S" x))
+ ((null (cdr x))
+ (error "too few subexpressions in feature expression: ~S" x))
+ (t (not (featurep (cadr x))))))
+ ((:and and) (every #'featurep (cdr x)))
+ ((:or or) (some #'featurep (cdr x)))
+ (t
+ (error "unknown operator in feature expression: ~S." x))))
+ (symbol (not (null (memq x *features*))))))
+\f
+;;;; utilities for two-VALUES predicates
+
+(defmacro not/type (x)
+ (let ((val (gensym "VAL"))
+ (win (gensym "WIN")))
+ `(multiple-value-bind (,val ,win)
+ ,x
+ (if ,win
+ (values (not ,val) t)
+ (values nil nil)))))
+
+(defmacro and/type (x y)
+ `(multiple-value-bind (val1 win1) ,x
+ (if (and (not val1) win1)
+ (values nil t)
+ (multiple-value-bind (val2 win2) ,y
+ (if (and val1 val2)
+ (values t t)
+ (values nil (and win2 (not val2))))))))
+
+;;; sort of like ANY and EVERY, except:
+;;; * We handle two-VALUES predicate functions, as SUBTYPEP does.
+;;; (And if the result is uncertain, then we return (VALUES NIL NIL),
+;;; as SUBTYPEP does.)
+;;; * THING is just an atom, and we apply OP (an arity-2 function)
+;;; successively to THING and each element of LIST.
+(defun any/type (op thing list)
+ (declare (type function op))
+ (let ((certain? t))
+ (dolist (i list (values nil certain?))
+ (multiple-value-bind (sub-value sub-certain?) (funcall op thing i)
+ (if sub-certain?
+ (when sub-value (return (values t t)))
+ (setf certain? nil))))))
+(defun every/type (op thing list)
+ (declare (type function op))
+ (let ((certain? t))
+ (dolist (i list (if certain? (values t t) (values nil nil)))
+ (multiple-value-bind (sub-value sub-certain?) (funcall op thing i)
+ (if sub-certain?
+ (unless sub-value (return (values nil t)))
+ (setf certain? nil))))))
\f
-#|
-;;; REMOVEME when done testing byte cross-compiler
-(defun byte-compiled-foo (x y)
- (declare (optimize (speed 0) (debug 1)))
- (if x
- x
- (cons y y)))
-|#
\ No newline at end of file
+;;;; DEFPRINTER
+
+;;; These functions are called by the expansion of the DEFPRINTER
+;;; macro to do the actual printing.
+(declaim (ftype (function (symbol t stream) (values))
+ defprinter-prin1 defprinter-princ))
+(defun defprinter-prin1 (name value stream)
+ (defprinter-prinx #'prin1 name value stream))
+(defun defprinter-princ (name value stream)
+ (defprinter-prinx #'princ name value stream))
+(defun defprinter-prinx (prinx name value stream)
+ (declare (type function prinx))
+ (when *print-pretty*
+ (pprint-newline :linear stream))
+ (format stream ":~A " name)
+ (funcall prinx value stream)
+ (values))
+(defun defprinter-print-space (stream)
+ (write-char #\space stream))
+
+;;; Define some kind of reasonable PRINT-OBJECT method for a
+;;; STRUCTURE-OBJECT class.
+;;;
+;;; NAME is the name of the structure class, and CONC-NAME is the same
+;;; as in DEFSTRUCT.
+;;;
+;;; The SLOT-DESCS describe how each slot should be printed. Each
+;;; SLOT-DESC can be a slot name, indicating that the slot should
+;;; simply be printed. A SLOT-DESC may also be a list of a slot name
+;;; and other stuff. The other stuff is composed of keywords followed
+;;; by expressions. The expressions are evaluated with the variable
+;;; which is the slot name bound to the value of the slot. These
+;;; keywords are defined:
+;;;
+;;; :PRIN1 Print the value of the expression instead of the slot value.
+;;; :PRINC Like :PRIN1, only PRINC the value
+;;; :TEST Only print something if the test is true.
+;;;
+;;; If no printing thing is specified then the slot value is printed
+;;; as if by PRIN1.
+;;;
+;;; The structure being printed is bound to STRUCTURE and the stream
+;;; is bound to STREAM.
+(defmacro defprinter ((name
+ &key
+ (conc-name (concatenate 'simple-string
+ (symbol-name name)
+ "-"))
+ identity)
+ &rest slot-descs)
+ (let ((first? t)
+ maybe-print-space
+ (reversed-prints nil)
+ (stream (sb!xc:gensym "STREAM")))
+ (flet ((sref (slot-name)
+ `(,(symbolicate conc-name slot-name) structure)))
+ (dolist (slot-desc slot-descs)
+ (if first?
+ (setf maybe-print-space nil
+ first? nil)
+ (setf maybe-print-space `(defprinter-print-space ,stream)))
+ (cond ((atom slot-desc)
+ (push maybe-print-space reversed-prints)
+ (push `(defprinter-prin1 ',slot-desc ,(sref slot-desc) ,stream)
+ reversed-prints))
+ (t
+ (let ((sname (first slot-desc))
+ (test t))
+ (collect ((stuff))
+ (do ((option (rest slot-desc) (cddr option)))
+ ((null option)
+ (push `(let ((,sname ,(sref sname)))
+ (when ,test
+ ,maybe-print-space
+ ,@(or (stuff)
+ `((defprinter-prin1
+ ',sname ,sname ,stream)))))
+ reversed-prints))
+ (case (first option)
+ (:prin1
+ (stuff `(defprinter-prin1
+ ',sname ,(second option) ,stream)))
+ (:princ
+ (stuff `(defprinter-princ
+ ',sname ,(second option) ,stream)))
+ (:test (setq test (second option)))
+ (t
+ (error "bad option: ~S" (first option)))))))))))
+ `(def!method print-object ((structure ,name) ,stream)
+ (pprint-logical-block (,stream nil)
+ (print-unreadable-object (structure
+ ,stream
+ :type t
+ :identity ,identity)
+ ,@(nreverse reversed-prints))))))
+\f
+;;;; etc.
+
+;;; Given a pathname, return a corresponding physical pathname.
+(defun physicalize-pathname (possibly-logical-pathname)
+ (if (typep possibly-logical-pathname 'logical-pathname)
+ (translate-logical-pathname possibly-logical-pathname)
+ possibly-logical-pathname))
+
+(defun deprecation-warning (bad-name &optional good-name)
+ (warn "using deprecated ~S~@[, should use ~S instead~]"
+ bad-name
+ good-name))
+
+;;; Anaphoric macros
+(defmacro awhen (test &body body)
+ `(let ((it ,test))
+ (when it ,@body)))
+
+(defmacro acond (&rest clauses)
+ (if (null clauses)
+ `()
+ (destructuring-bind ((test &body body) &rest rest) clauses
+ (once-only ((test test))
+ `(if ,test
+ (let ((it ,test)) (declare (ignorable it)),@body)
+ (acond ,@rest))))))
+
+;;; (binding* ({(names initial-value [flag])}*) body)
+;;; FLAG may be NIL or :EXIT-IF-NULL
+;;;
+;;; This form unites LET*, MULTIPLE-VALUE-BIND and AWHEN.
+(defmacro binding* ((&rest bindings) &body body)
+ (let ((bindings (reverse bindings)))
+ (loop with form = `(progn ,@body)
+ for binding in bindings
+ do (destructuring-bind (names initial-value &optional flag)
+ binding
+ (multiple-value-bind (names declarations)
+ (etypecase names
+ (null
+ (let ((name (gensym)))
+ (values (list name) `((declare (ignorable ,name))))))
+ (symbol
+ (values (list names) nil))
+ (list
+ (collect ((new-names) (ignorable))
+ (dolist (name names)
+ (when (eq name nil)
+ (setq name (gensym))
+ (ignorable name))
+ (new-names name))
+ (values (new-names)
+ (when (ignorable)
+ `((declare (ignorable ,@(ignorable)))))))))
+ (setq form `(multiple-value-bind ,names
+ ,initial-value
+ ,@declarations
+ ,(ecase flag
+ ((nil) form)
+ ((:exit-if-null)
+ `(when ,(first names) ,form)))))))
+ finally (return form))))
+\f
+;;; Delayed evaluation
+(defmacro delay (form)
+ `(cons nil (lambda () ,form)))
+
+(defun force (promise)
+ (cond ((not (consp promise)) promise)
+ ((car promise) (cdr promise))
+ (t (setf (car promise) t
+ (cdr promise) (funcall (cdr promise))))))
+
+(defun promise-ready-p (promise)
+ (or (not (consp promise))
+ (car promise)))
+\f
+;;; toplevel helper
+(defmacro with-rebound-io-syntax (&body body)
+ `(%with-rebound-io-syntax (lambda () ,@body)))
+
+(defun %with-rebound-io-syntax (function)
+ (declare (type function function))
+ (let ((*package* *package*)
+ (*print-array* *print-array*)
+ (*print-base* *print-base*)
+ (*print-case* *print-case*)
+ (*print-circle* *print-circle*)
+ (*print-escape* *print-escape*)
+ (*print-gensym* *print-gensym*)
+ (*print-length* *print-length*)
+ (*print-level* *print-level*)
+ (*print-lines* *print-lines*)
+ (*print-miser-width* *print-miser-width*)
+ (*print-pretty* *print-pretty*)
+ (*print-radix* *print-radix*)
+ (*print-readably* *print-readably*)
+ (*print-right-margin* *print-right-margin*)
+ (*read-base* *read-base*)
+ (*read-default-float-format* *read-default-float-format*)
+ (*read-eval* *read-eval*)
+ (*read-suppress* *read-suppress*)
+ (*readtable* *readtable*))
+ (funcall function)))
+
+;;; Bind a few "potentially dangerous" printer control variables to
+;;; safe values, respecting current values if possible.
+(defmacro with-sane-io-syntax (&body forms)
+ `(call-with-sane-io-syntax (lambda () ,@forms)))
+
+(defun call-with-sane-io-syntax (function)
+ (declare (type function function))
+ (macrolet ((true (sym)
+ `(and (boundp ',sym) ,sym)))
+ (let ((*print-readably* nil)
+ (*print-level* (or (true *print-level*) 6))
+ (*print-length* (or (true *print-length*) 12)))
+ (funcall function))))
+
+;;; Returns a list of members of LIST. Useful for dealing with circular lists.
+;;; For a dotted list returns a secondary value of T -- in which case the
+;;; primary return value does not include the dotted tail.
+(defun list-members (list)
+ (when list
+ (do ((tail (cdr list) (cdr tail))
+ (members (list (car list)) (cons (car tail) members)))
+ ((or (not (consp tail)) (eq tail list))
+ (values members (not (listp tail)))))))
+
+;;; Default evaluator mode (interpeter / compiler)
+
+(declaim (type (member :compile #!+sb-eval :interpret) *evaluator-mode*))
+(defparameter *evaluator-mode* :compile
+ #!+sb-doc
+ "Toggle between different evaluator implementations. If set to :COMPILE,
+an implementation of EVAL that calls the compiler will be used. If set
+to :INTERPRET, an interpreter will be used.")
+
+;;; Helper for making the DX closure allocation in macros expanding
+;;; to CALL-WITH-FOO less ugly.
+(defmacro dx-flet (functions &body forms)
+ `(flet ,functions
+ (declare (#+sb-xc-host dynamic-extent #-sb-xc-host truly-dynamic-extent
+ ,@(mapcar (lambda (func) `(function ,(car func))) functions)))
+ ,@forms))
+
+;;; Another similar one.
+(defmacro dx-let (bindings &body forms)
+ `(let ,bindings
+ (declare (#+sb-xc-host dynamic-extent #-sb-xc-host truly-dynamic-extent
+ ,@(mapcar (lambda (bind) (if (consp bind) (car bind) bind))
+ bindings)))
+ ,@forms))
+
+(in-package "SB!KERNEL")
+
+(defun fp-zero-p (x)
+ (typecase x
+ (single-float (zerop x))
+ (double-float (zerop x))
+ #!+long-float
+ (long-float (zerop x))
+ (t nil)))
+
+(defun neg-fp-zero (x)
+ (etypecase x
+ (single-float
+ (if (eql x 0.0f0)
+ (make-unportable-float :single-float-negative-zero)
+ 0.0f0))
+ (double-float
+ (if (eql x 0.0d0)
+ (make-unportable-float :double-float-negative-zero)
+ 0.0d0))
+ #!+long-float
+ (long-float
+ (if (eql x 0.0l0)
+ (make-unportable-float :long-float-negative-zero)
+ 0.0l0))))