X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Flate-extensions.lisp;h=0062618145fb396071b4081cc4575ff5ca085770;hb=57522083c49215cee67ddd85782b01872f4ec9ce;hp=afd2191efa01e6836a3026e95b8830468758f6c4;hpb=e5f24ebc38e38c986df830fd1e4035d16bea4e5c;p=sbcl.git diff --git a/src/code/late-extensions.lisp b/src/code/late-extensions.lisp index afd2191..0062618 100644 --- a/src/code/late-extensions.lisp +++ b/src/code/late-extensions.lisp @@ -1,3 +1,9 @@ +;;;; various extensions (including SB-INT "internal extensions") +;;;; available both in the cross-compilation host Lisp and in the +;;;; target SBCL, but which can't be defined on the target until until +;;;; some significant amount of machinery (e.g. error-handling) is +;;;; defined + ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. ;;;; @@ -9,85 +15,291 @@ (in-package "SB!IMPL") -(defun featurep (x) - #!+sb-doc - "If X is an atom, see whether it is present in *FEATURES*. Also - handle arbitrary combinations of atoms using NOT, AND, OR." - (if (consp x) - (case (car x) - ((:not not) - (if (cddr x) - (error "too many subexpressions in feature expression: ~S" x) - (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))) - (not (null (memq x *features*))))) - -;;; KLUDGE: This is a wrapper around stale code for working with floating point -;;; infinities. I believe that I will eventually eliminate floating point -;;; infinities from the code, since they're a pain to cross-compile, since they -;;; significantly increase the number of conditions which need to be tested in -;;; numeric functions, and since the benefits which they provide (which are -;;; admittedly significant) are unfortunately not portable. I haven't actually -;;; done the dirty deed yet, though, and until then, I've wrapped various -;;; infinity-returning forms in this macro. -- WHN 1999 -(defmacro infinite (x) - (declare (ignorable x)) - #!-sb-infinities '(error 'floating-point-overflow) - #!+sb-infinities x) - -;;; Given a list of keyword substitutions `(,OLD ,NEW), and a -;;; keyword-argument-list-style list of alternating keywords and arbitrary -;;; values, return a new keyword-argument-list-style list with all -;;; substitutions applied to it. -;;; -;;; Note: If efficiency mattered, we could do less consing. (But if efficiency -;;; mattered, why would we be using keyword arguments at all, much less -;;; renaming keyword arguments?) +;;; Is X a list for which LENGTH is meaningful, i.e. a list which is +;;; not improper and which is not circular? +(defun list-with-length-p (x) + (values (ignore-errors (list-length x)))) + +;;; not used in 0.7.8, but possibly useful for defensive programming +;;; in e.g. (COERCE ... 'VECTOR) +;;;(defun list-length-or-die (x) +;;; (or (list-length x) +;;; ;; not clear how to do this best: +;;; ;; * Should this be a TYPE-ERROR? Colloquially that'd make +;;; ;; lots of sense, but since I'm not sure how to express +;;; ;; "noncircular list" as a Lisp type expression, coding +;;; ;; it seems awkward. +;;; ;; * Should the ERROR object include the offending value? +;;; ;; Ordinarily that's helpful, but if the user doesn't have +;;; ;; his printer set up to deal with cyclicity, we might not +;;; ;; be doing him a favor by printing the object here. +;;; ;; -- WHN 2002-10-19 +;;; (error "can't calculate length of cyclic list"))) + +;;; This is used in constructing arg lists for debugger printing, +;;; and when needing to print unbound slots in PCL. +(defstruct (unprintable-object + (:constructor make-unprintable-object (string)) + (:print-object (lambda (x s) + (print-unreadable-object (x s) + (write-string (unprintable-object-string x) s)))) + (:copier nil)) + string) + +;;; Used internally, but it would be nice to provide something +;;; like this for users as well. ;;; -;;; KLUDGE: It would probably be good to get rid of this. -- WHN 19991201 -(defun rename-keyword-args (rename-list keyword-args) - (declare (type list rename-list keyword-args)) - ;; Walk through RENAME-LIST modifying RESULT as per each element in - ;; RENAME-LIST. - (do ((result (copy-list keyword-args))) ; may be modified below - ((null rename-list) result) - (destructuring-bind (old new) (pop rename-list) - (declare (type keyword old new)) - ;; Walk through RESULT renaming any OLD keyword argument to NEW. - (do ((in-result result (cddr in-result))) - ((null in-result)) - (declare (type list in-result)) - (when (eq (car in-result) old) - (setf (car in-result) new)))))) - -;;; ANSI Common Lisp's READ-SEQUENCE function, unlike most of the -;;; other ANSI input functions, is defined to communicate end of file -;;; status with its return value, not by signalling. This is not the -;;; behavior we usually want. This is a wrapper which give the -;;; behavior we usually want, causing READ-SEQUENCE to communicate -;;; end-of-file status by signalling. -(defun read-sequence-or-die (sequence stream &key start end) - ;; implementation using READ-SEQUENCE - #-no-ansi-read-sequence - (let ((read-end (read-sequence sequence - stream - :start start - :end end))) - (unless (= read-end end) - (error 'end-of-file :stream stream)) - (values)) - ;; workaround for broken READ-SEQUENCE - #+no-ansi-read-sequence - (progn - (assert (<= start end)) - (let ((etype (stream-element-type stream))) - (cond ((equal etype '(unsigned-byte 8)) - (do ((i start (1+ i))) - ((>= i end) - (values)) - (setf (aref sequence i) - (read-byte stream)))) - (t (error "unsupported element type ~S" etype)))))) +;;; FIXME / IMPORTANT: If the slot is raw, the address is correct only for +;;; instances of the specified class, not its subclasses! +#!+sb-thread +(defmacro define-structure-slot-addressor (name &key structure slot) + (let* ((dd (find-defstruct-description structure t)) + (slotd (when dd (find slot (dd-slots dd) :key #'dsd-name))) + (index (when slotd (dsd-index slotd))) + (raw-type (dsd-raw-type slotd))) + (unless index + (error "Slot ~S not found in ~S." slot structure)) + `(progn + (declaim (inline ,name)) + (defun ,name (instance) + (declare (type ,structure instance) (optimize speed)) + (sb!ext:truly-the + sb!vm:word + (+ (sb!kernel:get-lisp-obj-address instance) + (- (* ,(if (eq t raw-type) + (+ sb!vm:instance-slots-offset index) + (- (1+ (sb!kernel::dd-instance-length dd)) sb!vm:instance-slots-offset index + (1- (sb!kernel::raw-slot-words raw-type)))) + sb!vm:n-word-bytes) + sb!vm:instance-pointer-lowtag))))))) + +(defmacro compare-and-swap (place old new &environment env) + "Atomically stores NEW in PLACE if OLD matches the current value of PLACE. +Two values are considered to match if they are EQ. Returns the previous value +of PLACE: if the returned value is EQ to OLD, the swap was carried out. + +PLACE must be an accessor form whose CAR is one of the following: + + CAR, CDR, FIRST, REST, SYMBOL-PLIST, SYMBOL-VALUE, SVREF + +or the name of a DEFSTRUCT created accessor for a slot whose declared type is +either FIXNUM or T. Results are unspecified if the slot has a declared type +other then FIXNUM or T. + +EXPERIMENTAL: Interface subject to change." + (flet ((invalid-place () + (error "Invalid first argument to COMPARE-AND-SWAP: ~S" place))) + (unless (consp place) + (invalid-place)) + ;; FIXME: Not the nicest way to do this... + (destructuring-bind (op &rest args) place + (case op + ((car first) + `(%compare-and-swap-car (the cons ,@args) ,old ,new)) + ((cdr rest) + `(%compare-and-swap-cdr (the cons ,@args) ,old ,new)) + (symbol-plist + `(%compare-and-swap-symbol-plist (the symbol ,@args) ,old (the list ,new))) + (symbol-value + (destructuring-bind (name) args + (flet ((slow (symbol) + (with-unique-names (n-symbol n-old n-new) + `(let ((,n-symbol ,symbol) + (,n-old ,old) + (,n-new ,new)) + (declare (symbol ,n-symbol)) + (about-to-modify-symbol-value ,n-symbol 'compare-and-swap ,n-new) + (%compare-and-swap-symbol-value ,n-symbol ,n-old ,n-new))))) + (if (sb!xc:constantp name env) + (let ((cname (constant-form-value name env))) + (if (eq :special (info :variable :kind cname)) + ;; Since we know the symbol is a special, we can just generate + ;; the type check. + `(%compare-and-swap-symbol-value + ',cname ,old (the ,(info :variable :type cname) ,new)) + (slow (list 'quote cname)))) + (slow name))))) + (svref + (let ((vector (car args)) + (index (cadr args))) + (unless (and vector index (not (cddr args))) + (invalid-place)) + (with-unique-names (v) + `(let ((,v ,vector)) + (declare (simple-vector ,v)) + (%compare-and-swap-svref ,v (%check-bound ,v (length ,v) ,index) ,old ,new))))) + (t + (let ((dd (info :function :structure-accessor op))) + (if dd + (let* ((structure (dd-name dd)) + (slotd (find op (dd-slots dd) :key #'dsd-accessor-name)) + (index (dsd-index slotd)) + (type (dsd-type slotd))) + (unless (eq t (dsd-raw-type slotd)) + (error "Cannot use COMPARE-AND-SWAP with structure accessor for a typed slot: ~S" + place)) + (when (dsd-read-only slotd) + (error "Cannot use COMPARE-AND-SWAP with structure accessor for a read-only slot: ~S" + place)) + `(truly-the (values ,type &optional) + (%compare-and-swap-instance-ref (the ,structure ,@args) + ,index + (the ,type ,old) (the ,type ,new)))) + (error "Invalid first argument to COMPARE-AND-SWAP: ~S" place)))))))) + +(macrolet ((def (name lambda-list ref &optional set) + #!+compare-and-swap-vops + (declare (ignore ref set)) + `(defun ,name (,@lambda-list old new) + #!+compare-and-swap-vops + (,name ,@lambda-list old new) + #!-compare-and-swap-vops + (let ((current (,ref ,@lambda-list))) + (when (eq current old) + ,(if set + `(,set ,@lambda-list new) + `(setf (,ref ,@lambda-list) new))) + current)))) + (def %compare-and-swap-car (cons) car) + (def %compare-and-swap-cdr (cons) cdr) + (def %compare-and-swap-instance-ref (instance index) %instance-ref %instance-set) + (def %compare-and-swap-symbol-plist (symbol) symbol-plist) + (def %compare-and-swap-symbol-value (symbol) symbol-value) + (def %compare-and-swap-svref (vector index) svref)) + +(defun expand-atomic-frob (name place diff) + (flet ((invalid-place () + (error "Invalid first argument to ~S: ~S" name place))) + (unless (consp place) + (invalid-place)) + (destructuring-bind (op &rest args) place + (when (cdr args) + (invalid-place)) + (let ((dd (info :function :structure-accessor op))) + (if dd + (let* ((structure (dd-name dd)) + (slotd (find op (dd-slots dd) :key #'dsd-accessor-name)) + (index (dsd-index slotd)) + (type (dsd-type slotd))) + (declare (ignorable structure index)) + (unless (and (eq 'sb!vm:word (dsd-raw-type slotd)) + (type= (specifier-type type) (specifier-type 'sb!vm:word))) + (error "~S requires a slot of type (UNSIGNED-BYTE ~S), not ~S: ~S" + name sb!vm:n-word-bits type place)) + (when (dsd-read-only slotd) + (error "Cannot use ~S with structure accessor for a read-only slot: ~S" + name place)) + #!+(or x86 x86-64 ppc) + `(truly-the sb!vm:word + (%raw-instance-atomic-incf/word + (the ,structure ,@args) ,index + (logand #.(1- (ash 1 sb!vm:n-word-bits)) + ,(ecase name + (atomic-incf + `(the sb!vm:signed-word ,diff)) + (atomic-decf + `(- (the sb!vm:signed-word ,diff))))))) + ;; No threads outside x86 and x86-64 for now, so this is easy... + #!-(or x86 x86-64 ppc) + (with-unique-names (structure old) + `(sb!sys:without-interrupts + (let* ((,structure ,@args) + (,old (,op ,structure))) + (setf (,op ,structure) + (logand #.(1- (ash 1 sb!vm:n-word-bits)) + ,(ecase name + (atomic-incf + `(+ ,old (the sb!vm:signed-word ,diff))) + (atomic-decf + `(- ,old (the sb!vm:signed-word ,diff)))))) + ,old)))) + (invalid-place)))))) + +(defmacro atomic-incf (place &optional (diff 1)) + #!+sb-doc + "Atomically increments PLACE by DIFF, and returns the value of PLACE before +the increment. + +The incrementation is done using word-size modular arithmetic: on 32 bit +platforms ATOMIC-INCF of #xFFFFFFFF by one results in #x0 being stored in +PLACE. + +PLACE must be an accessor form whose CAR is the name of a DEFSTRUCT accessor +whose declared type is (UNSIGNED-BYTE 32) on 32 bit platforms, +and (UNSIGNED-BYTE 64) on 64 bit platforms -- the type SB-EXT:WORD can be used +for this purpose. + +DIFF defaults to 1, and must be a (SIGNED-BYTE 32) on 32 bit platforms, +and (SIGNED-BYTE 64) on 64 bit platforms. + +EXPERIMENTAL: Interface subject to change." + (expand-atomic-frob 'atomic-incf place diff)) + +(defmacro atomic-decf (place &optional (diff 1)) + #!+sb-doc + "Atomically decrements PLACE by DIFF, and returns the value of PLACE before +the increment. + +The decrementation is done using word-size modular arithmetic: on 32 bit +platforms ATOMIC-DECF of #x0 by one results in #xFFFFFFFF being stored in +PLACE. + +PLACE must be an accessor form whose CAR is the name of a DEFSTRUCT accessor +whose declared type is (UNSIGNED-BYTE 32) on 32 bit platforms, +and (UNSIGNED-BYTE 64) on 64 bit platforms -- the type SB-EXT:WORD can be used +for this purpose. + +DIFF defaults to 1, and must be a (SIGNED-BYTE 32) on 32 bit platforms, +and (SIGNED-BYTE 64) on 64 bit platforms. + +EXPERIMENTAL: Interface subject to change." + (expand-atomic-frob 'atomic-decf place diff)) + +(defun call-hooks (kind hooks &key (on-error :error)) + (dolist (hook hooks) + (handler-case + (funcall hook) + (serious-condition (c) + (if (eq :warn on-error) + (warn "Problem running ~A hook ~S:~% ~A" kind hook c) + (with-simple-restart (continue "Skip this ~A hook." kind) + (error "Problem running ~A hook ~S:~% ~A" kind hook c))))))) + +;;;; DEFGLOBAL + +(defmacro-mundanely defglobal (name value &optional (doc nil docp)) + #!+sb-doc + "Defines NAME as a global variable that is always bound. VALUE is evaluated +and assigned to NAME both at compile- and load-time, but only if NAME is not +already bound. + +Global variables share their values between all threads, and cannot be +locally bound, declared special, defined as constants, and neither bound +nor defined as symbol macros. + +See also the declarations SB-EXT:GLOBAL and SB-EXT:ALWAYS-BOUND." + `(progn + (eval-when (:compile-toplevel) + (let ((boundp (boundp ',name))) + (%compiler-defglobal ',name (unless boundp ,value) boundp))) + (eval-when (:load-toplevel :execute) + (let ((boundp (boundp ',name))) + (%defglobal ',name (unless boundp ,value) boundp ',doc ,docp + (sb!c:source-location)))))) + +(defun %compiler-defglobal (name value boundp) + (sb!xc:proclaim `(global ,name)) + (unless boundp + #-sb-xc-host + (set-symbol-global-value name value) + #+sb-xc-host + (set name value)) + (sb!xc:proclaim `(always-bound ,name))) + +(defun %defglobal (name value boundp doc docp source-location) + (%compiler-defglobal name value boundp) + (when docp + (setf (fdocumentation name 'variable) doc)) + (sb!c:with-source-location (source-location) + (setf (info :source-location :variable name) source-location)) + name)