X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Flate-extensions.lisp;h=48ee19018a5a4bb5293aed29a97caf77fa574ac0;hb=4f4906712a4fa98880fb0f8f036ca2add541b8a1;hp=a841f908b461a8c2eac849e5ef59ac95401eeaa2;hpb=4898ef32c639b1c7f4ee13a5ba566ce6debd03e6;p=sbcl.git diff --git a/src/code/late-extensions.lisp b/src/code/late-extensions.lisp index a841f90..48ee190 100644 --- a/src/code/late-extensions.lisp +++ b/src/code/late-extensions.lisp @@ -35,3 +35,404 @@ ;;; ;; 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))))))) + +;;;; ATOMIC-INCF and ATOMIC-DECF + +(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 + (case op + (aref + (when (cddr args) + (invalid-place)) + #!+(or x86 x86-64 ppc) + (with-unique-names (array) + `(let ((,array (the (simple-array sb!ext:word (*)) ,(car args)))) + (%array-atomic-incf/word + ,array + (%check-bound ,array (array-dimension ,array 0) ,(cadr args)) + (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)))))))) + #!-(or x86 x86-64 ppc) + (with-unique-names (array index old-value) + (let ((incremented-value + (ecase name + (atomic-incf + `(+ ,old-value (the sb!vm:signed-word ,diff))) + (atomic-decf + `(- ,old-value (the sb!vm:signed-word ,diff)))))) + `(sb!sys:without-interrupts + (let* ((,array ,(car args)) + (,index ,(cadr args)) + (,old-value (aref ,array ,index))) + (setf (aref ,array ,index) + (logand #.(1- (ash 1 sb!vm:n-word-bits)) + ,incremented-value)) + ,old-value))))) + (t + (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 or an AREF of a (SIMPLE-ARRAY +SB-EXT:WORD (*) -- 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 or an AREF of a (SIMPLE-ARRAY +SB-EXT:WORD (*) -- 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)) + +;; Interpreter stubs for ATOMIC-INCF. +#!+(or x86 x86-64 ppc) +(defun %array-atomic-incf/word (array index diff) + (declare (type (simple-array word (*)) array) + (fixnum index) + (type sb!vm:signed-word diff)) + (%array-atomic-incf/word array index diff)) + +(defun spin-loop-hint () + #!+sb-doc + "Hints the processor that the current thread is spin-looping." + (spin-loop-hint)) + +(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) + +;;;; WAIT-FOR -- waiting on arbitrary conditions + +(defun %%wait-for (test stop-sec stop-usec) + (declare (function test)) + (labels ((try () + (declare (optimize (safety 0))) + (awhen (funcall test) + (return-from %%wait-for it))) + (tick (sec usec) + (declare (fixnum sec usec)) + ;; TICK is microseconds + (+ usec (* 1000000 sec))) + (get-tick () + (multiple-value-call #'tick + (decode-internal-time (get-internal-real-time))))) + (let* ((timeout-tick (when stop-sec (tick stop-sec stop-usec))) + (start (get-tick)) + ;; Rough estimate of how long a single attempt takes. + (try-ticks (progn + (try) (try) (try) + (max 1 (truncate (- (get-tick) start) 3))))) + ;; Scale sleeping between attempts: + ;; + ;; Start by sleeping for as many ticks as an average attempt + ;; takes, then doubling for each attempt. + ;; + ;; Max out at 0.1 seconds, or the 2 x time of a single try, + ;; whichever is longer -- with a hard cap of 10 seconds. + ;; + ;; FIXME: Maybe the API should have a :MAX-SLEEP argument? + (loop with max-ticks = (max 100000 (min (* 2 try-ticks) + (expt 10 7))) + for scale of-type fixnum = 1 + then (let ((x (logand most-positive-fixnum (* 2 scale)))) + (if (> scale x) + most-positive-fixnum + x)) + do (try) + (let* ((now (get-tick)) + (sleep-ticks (min (* try-ticks scale) max-ticks)) + (sleep + (if timeout-tick + ;; If sleep would take us past the + ;; timeout, shorten it so it's just + ;; right. + (if (>= (+ now sleep-ticks) timeout-tick) + (- timeout-tick now) + sleep-ticks) + sleep-ticks))) + (declare (fixnum sleep)) + (cond ((plusp sleep) + ;; microseconds to seconds and nanoseconds + (multiple-value-bind (sec nsec) + (truncate (* 1000 sleep) (expt 10 9)) + (with-interrupts + (sb!unix:nanosleep sec nsec)))) + (t + (return-from %%wait-for nil)))))))) + +(defun %wait-for (test timeout) + (declare (function test)) + (tagbody + :restart + (multiple-value-bind (to-sec to-usec stop-sec stop-usec deadlinep) + (decode-timeout timeout) + (declare (ignore to-sec to-usec)) + (return-from %wait-for + (or (%%wait-for test stop-sec stop-usec) + (when deadlinep + (signal-deadline) + (go :restart))))))) + +(defmacro wait-for (test-form &key timeout) + #!+sb-doc + "Wait until TEST-FORM evaluates to true, then return its primary value. +If TIMEOUT is provided, waits at most approximately TIMEOUT seconds before +returning NIL. + +If WITH-DEADLINE has been used to provide a global deadline, signals a +DEADLINE-TIMEOUT if TEST-FORM doesn't evaluate to true before the +deadline. + +Experimental: subject to change without prior notice." + `(dx-flet ((wait-for-test () (progn ,test-form))) + (%wait-for #'wait-for-test ,timeout))) + +(defmacro with-progressive-timeout ((name &key seconds) + &body body) + #!+sb-doc + "Binds NAME as a local function for BODY. Each time #'NAME is called, it +returns SECONDS minus the time that has elapsed since BODY was entered, or +zero if more time than SECONDS has elapsed. If SECONDS is NIL, #'NAME +returns NIL each time." + (with-unique-names (deadline time-left sec) + `(let* ((,sec ,seconds) + (,deadline + (when ,sec + (+ (get-internal-real-time) + (round (* ,seconds internal-time-units-per-second)))))) + (flet ((,name () + (when ,deadline + (let ((,time-left (- ,deadline (get-internal-real-time)))) + (if (plusp ,time-left) + (* (coerce ,time-left 'single-float) + ,(/ 1.0 internal-time-units-per-second)) + 0))))) + ,@body)))) + +(defmacro atomic-update (place update-fn &rest arguments &environment env) + #!+sb-doc + "Updates PLACE atomically to the value returned by calling function +designated by UPDATE-FN with ARGUMENTS and the previous value of PLACE. + +PLACE may be read and UPDATE-FN evaluated and called multiple times before the +update succeeds: atomicity in this context means that value of place did not +change between the time it was read, and the time it was replaced with the +computed value. + +PLACE can be any place supported by SB-EXT:COMPARE-AND-SWAP. + +Examples: + + ;;; Conses T to the head of FOO-LIST. + (defstruct foo list) + (defvar *foo* (make-foo)) + (atomic-update (foo-list *foo*) #'cons t) + + (let ((x (cons :count 0))) + (mapc #'sb-thread:join-thread + (loop repeat 1000 + collect (sb-thread:make-thread + (lambda () + (loop repeat 1000 + do (atomic-update (cdr x) #'1+) + (sleep 0.00001)))))) + ;; Guaranteed to be (:COUNT . 1000000) -- if you replace + ;; atomic update with (INCF (CDR X)) above, the result becomes + ;; unpredictable. + x) +" + (multiple-value-bind (vars vals old new cas-form read-form) + (get-cas-expansion place env) + `(let* (,@(mapcar 'list vars vals) + (,old ,read-form)) + (loop for ,new = (funcall ,update-fn ,@arguments ,old) + until (eq ,old (setf ,old ,cas-form)) + finally (return ,new))))) + +(defmacro atomic-push (obj place &environment env) + #!+sb-doc + "Like PUSH, but atomic. PLACE may be read multiple times before +the operation completes -- the write does not occur until such time +that no other thread modified PLACE between the read and the write. + +Works on all CASable places." + (multiple-value-bind (vars vals old new cas-form read-form) + (get-cas-expansion place env) + `(let* (,@(mapcar 'list vars vals) + (,old ,read-form) + (,new (cons ,obj ,old))) + (loop until (eq ,old (setf ,old ,cas-form)) + do (setf (cdr ,new) ,old) + finally (return ,new))))) + +(defmacro atomic-pop (place &environment env) + #!+sb-doc + "Like POP, but atomic. PLACE may be read multiple times before +the operation completes -- the write does not occur until such time +that no other thread modified PLACE between the read and the write. + +Works on all CASable places." + (multiple-value-bind (vars vals old new cas-form read-form) + (get-cas-expansion place env) + `(let* (,@(mapcar 'list vars vals)) + (loop for ,old = ,read-form + for ,new = (cdr ,old) + until (eq ,old (setf ,old ,cas-form)) + finally (return (car ,old))))))