X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Flate-extensions.lisp;h=0d1febeece52465f2adcd48d7aa31621bf006a41;hb=aa1a5c6ea31c248587d78f62943ad749ea8fbe2f;hp=4b71114f62ce670d525de01e87fdf35d6be16efe;hpb=c41d75f1d2defd6234e644ef2b40440a5d1526c5;p=sbcl.git diff --git a/src/code/late-extensions.lisp b/src/code/late-extensions.lisp index 4b71114..0d1febe 100644 --- a/src/code/late-extensions.lisp +++ b/src/code/late-extensions.lisp @@ -20,12 +20,12 @@ (defun list-with-length-p (x) (values (ignore-errors (list-length x)))) -;;; not used in 0.7.8, but possibly useful for defensive programming +;;; 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 +;;; ;; * 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. @@ -35,3 +35,198 @@ ;;; ;; 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. +;;; +;;; 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 if 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 SYMBOL-VALUE of ~S" ,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)) + +(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. + +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." + (flet ((invalid-place () + (error "Invalid first argument to ATOMIC-INCF: ~S" 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 "ATOMIC-INCF requires a slot of type (UNSIGNED-BYTE ~S), not ~S: ~S" + sb!vm:n-word-bits type place)) + (when (dsd-read-only slotd) + (error "Cannot use ATOMIC-INCF with structure accessor for a read-only slot: ~S" + place)) + #!+(or x86 x86-64) + `(truly-the sb!vm:word + (%raw-instance-atomic-incf/word (the ,structure ,@args) + ,index + (the sb!vm:signed-word ,diff))) + ;; No threads outside x86 and x86-64 for now, so this is easy... + #!-(or x86 x86-64) + (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)) + (+ ,old (the sb!vm:signed-word ,diff)))) + ,old)))) + (invalid-place)))))) + +(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)))))))