X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Flate-extensions.lisp;h=0062618145fb396071b4081cc4575ff5ca085770;hb=57522083c49215cee67ddd85782b01872f4ec9ce;hp=52b45c6c7af2bbb85f9adc0e65d5985d2d92bbb5;hpb=ea3a2433c72ee97c5691c29d882a63e4d86f0a32;p=sbcl.git diff --git a/src/code/late-extensions.lisp b/src/code/late-extensions.lisp index 52b45c6..0062618 100644 --- a/src/code/late-extensions.lisp +++ b/src/code/late-extensions.lisp @@ -48,32 +48,15 @@ ;;; Used internally, but it would be nice to provide something ;;; like this for users as well. -#!+sb-thread -(defmacro define-structure-slot-compare-and-swap - (name &key structure slot) - (let* ((dd (find-defstruct-description structure t)) - (slotd (when dd (find slot (dd-slots dd) :key #'dsd-name))) - (type (when slotd (dsd-type slotd))) - (index (when slotd (dsd-index slotd)))) - (unless index - (error "Slot ~S not found in ~S." slot structure)) - (unless (eq t (dsd-raw-type slotd)) - (error "Cannot define compare-and-swap on a raw slot.")) - (when (dsd-read-only slotd) - (error "Cannot define compare-and-swap on a read-only slot.")) - `(progn - (declaim (inline ,name)) - (defun ,name (instance old new) - (declare (type ,structure instance) - (type ,type old new)) - (%instance-compare-and-swap instance ,index old new))))) - -;;; Ditto +;;; +;;; 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)))) + (index (when slotd (dsd-index slotd))) + (raw-type (dsd-raw-type slotd))) (unless index (error "Slot ~S not found in ~S." slot structure)) `(progn @@ -83,6 +66,240 @@ (sb!ext:truly-the sb!vm:word (+ (sb!kernel:get-lisp-obj-address instance) - (- (* ,(+ sb!vm:instance-slots-offset index) sb!vm:n-word-bytes) + (- (* ,(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)