(in-package "SB-PCL")
-(sb-int:file-comment
- "$Header$")
-\f
-;;; This file is (almost) functionally equivalent to dlap.lisp, but easier to
-;;; read.
-;;; Might generate faster code, too, depending on the compiler and whether an
-;;; implementation-specific lap assembler was used.
+;;;; some support stuff for getting a hold of symbols that we need when
+;;;; building the discriminator codes. It's OK for these to be interned
+;;;; symbols because we don't capture any user code in the scope in which
+;;;; these symbols are bound.
+
+(declaim (list *dfun-arg-symbols*))
+(defvar *dfun-arg-symbols* '(.ARG0. .ARG1. .ARG2. .ARG3.))
+
+(defun dfun-arg-symbol (arg-number)
+ (or (nth arg-number *dfun-arg-symbols*)
+ (format-symbol *pcl-package* ".ARG~A." arg-number)))
+
+(declaim (list *slot-vector-symbols*))
+(defvar *slot-vector-symbols* '(.SLOTS0. .SLOTS1. .SLOTS2. .SLOTS3.))
+
+(defun slot-vector-symbol (arg-number)
+ (or (nth arg-number *slot-vector-symbols*)
+ (format-symbol *pcl-package* ".SLOTS~A." arg-number)))
+
+(declaim (inline make-dfun-required-args))
+(defun make-dfun-required-args (count)
+ (declare (type index count))
+ (let (result)
+ (dotimes (i count (nreverse result))
+ (push (dfun-arg-symbol i) result))))
+
+(defun make-dfun-lambda-list (nargs applyp)
+ (let ((required (make-dfun-required-args nargs)))
+ (if applyp
+ (nconc required
+ ;; Use &MORE arguments to avoid consing up an &REST list
+ ;; that we might not need at all. See MAKE-EMF-CALL and
+ ;; INVOKE-EFFECTIVE-METHOD-FUNCTION for the other
+ ;; pieces.
+ '(&more .dfun-more-context. .dfun-more-count.))
+ required)))
+
+(defun make-dlap-lambda-list (nargs applyp)
+ (let* ((required (make-dfun-required-args nargs))
+ (lambda-list (if applyp
+ (append required '(&more .more-context. .more-count.))
+ required)))
+ ;; Return the full lambda list, the required arguments, a form
+ ;; that will generate a rest-list, and a list of the &MORE
+ ;; parameters used.
+ (values lambda-list
+ required
+ (when applyp
+ '((sb-c::%listify-rest-args
+ .more-context.
+ (the (and unsigned-byte fixnum)
+ .more-count.))))
+ (when applyp
+ '(.more-context. .more-count.)))))
+
+(defun make-emf-call (nargs applyp fn-variable &optional emf-type)
+ (let ((required (make-dfun-required-args nargs)))
+ `(,(if (eq emf-type 'fast-method-call)
+ 'invoke-effective-method-function-fast
+ 'invoke-effective-method-function)
+ ,fn-variable
+ ,applyp
+ :required-args ,required
+ ;; INVOKE-EFFECTIVE-METHOD-FUNCTION will decide whether to use
+ ;; the :REST-ARG version or the :MORE-ARG version depending on
+ ;; the type of the EMF.
+ :rest-arg ,(if applyp
+ ;; Creates a list from the &MORE arguments.
+ '((sb-c::%listify-rest-args
+ .dfun-more-context.
+ (the (and unsigned-byte fixnum)
+ .dfun-more-count.)))
+ nil)
+ :more-arg ,(when applyp
+ '(.dfun-more-context. .dfun-more-count.)))))
+
+(defun make-fast-method-call-lambda-list (nargs applyp)
+ (list* '.pv. '.next-method-call. (make-dfun-lambda-list nargs applyp)))
+\f
+;;; Emitting various accessors.
(defun emit-one-class-reader (class-slot-p)
(emit-reader/writer :reader 1 class-slot-p))
+(defun emit-one-class-boundp (class-slot-p)
+ (emit-reader/writer :boundp 1 class-slot-p))
+
(defun emit-one-class-writer (class-slot-p)
(emit-reader/writer :writer 1 class-slot-p))
(defun emit-two-class-reader (class-slot-p)
(emit-reader/writer :reader 2 class-slot-p))
+(defun emit-two-class-boundp (class-slot-p)
+ (emit-reader/writer :boundp 2 class-slot-p))
+
(defun emit-two-class-writer (class-slot-p)
(emit-reader/writer :writer 2 class-slot-p))
(defun emit-one-index-readers (class-slot-p)
(emit-one-or-n-index-reader/writer :reader nil class-slot-p))
+(defun emit-one-index-boundps (class-slot-p)
+ (emit-one-or-n-index-reader/writer :boundp nil class-slot-p))
+
(defun emit-one-index-writers (class-slot-p)
(emit-one-or-n-index-reader/writer :writer nil class-slot-p))
(defun emit-n-n-readers ()
(emit-one-or-n-index-reader/writer :reader t nil))
+(defun emit-n-n-boundps ()
+ (emit-one-or-n-index-reader/writer :boundp t nil))
+
(defun emit-n-n-writers ()
(emit-one-or-n-index-reader/writer :writer t nil))
;;; --------------------------------
+;;; FIXME: What do these variables mean?
(defvar *precompiling-lap* nil)
-(defvar *emit-function-p* t)
(defun emit-default-only (metatypes applyp)
- (when (and (null *precompiling-lap*) *emit-function-p*)
- (return-from emit-default-only
- (emit-default-only-function metatypes applyp)))
- (let* ((dlap-lambda-list (make-dlap-lambda-list metatypes applyp))
- (args (remove '&rest dlap-lambda-list))
- (restl (when applyp '(.lap-rest-arg.))))
+ (multiple-value-bind (lambda-list args rest-arg more-arg)
+ (make-dlap-lambda-list (length metatypes) applyp)
(generating-lisp '(emf)
- dlap-lambda-list
- `(invoke-effective-method-function emf ,applyp ,@args ,@restl))))
-
-(defmacro emit-default-only-macro (metatypes applyp)
- (let ((*emit-function-p* nil)
- (*precompiling-lap* t))
- (values
- (emit-default-only metatypes applyp))))
+ lambda-list
+ `(invoke-effective-method-function emf
+ ,applyp
+ :required-args ,args
+ :more-arg ,more-arg
+ :rest-arg ,rest-arg))))
;;; --------------------------------
(defun generating-lisp (closure-variables args form)
- (let* ((rest (memq '&rest args))
- (ldiff (and rest (ldiff args rest)))
- (args (if rest (append ldiff '(&rest .lap-rest-arg.)) args))
- (lambda `(lambda ,closure-variables
- ,@(when (member 'miss-fn closure-variables)
- `((declare (type function miss-fn))))
- #'(sb-kernel:instance-lambda ,args
- (let ()
- (declare #.*optimize-speed*)
- ,form)))))
+ (let ((lambda `(lambda ,closure-variables
+ ,@(when (member 'miss-fn closure-variables)
+ `((declare (type function miss-fn))))
+ #'(lambda ,args
+ (let ()
+ (declare #.*optimize-speed*)
+ ,form)))))
(values (if *precompiling-lap*
- `#',lambda
- (compile-lambda lambda))
- nil)))
+ `#',lambda
+ (compile nil lambda))
+ nil)))
;;; note on implementation for CMU 17 and later (including SBCL):
-;;; Since std-instance-p is weakened, that branch may run on non-pcl
+;;; Since STD-INSTANCE-P is weakened, that branch may run on non-PCL
;;; instances (structures). The result will be the non-wrapper layout
;;; for the structure, which will cause a miss. The "slots" will be
;;; whatever the first slot is, but will be ignored. Similarly,
-;;; fsc-instance-p returns true on funcallable structures as well as
+;;; FSC-INSTANCE-P returns true on funcallable structures as well as
;;; PCL fins.
(defun emit-reader/writer (reader/writer 1-or-2-class class-slot-p)
- (when (and (null *precompiling-lap*) *emit-function-p*)
- (return-from emit-reader/writer
- (emit-reader/writer-function reader/writer 1-or-2-class class-slot-p)))
(let ((instance nil)
- (arglist ())
- (closure-variables ())
- (field (first-wrapper-cache-number-index))
- (readp (eq reader/writer :reader))
- (read-form (emit-slot-read-form class-slot-p 'index 'slots)))
- ;;we need some field to do the fast obsolete check
+ (arglist ())
+ (closure-variables ())
+ (read-form (emit-slot-read-form class-slot-p 'index 'slots)))
(ecase reader/writer
- (:reader (setq instance (dfun-arg-symbol 0)
- arglist (list instance)))
+ ((:reader :boundp)
+ (setq instance (dfun-arg-symbol 0)
+ arglist (list instance)))
(:writer (setq instance (dfun-arg-symbol 1)
- arglist (list (dfun-arg-symbol 0) instance))))
+ arglist (list (dfun-arg-symbol 0) instance))))
(ecase 1-or-2-class
(1 (setq closure-variables '(wrapper-0 index miss-fn)))
(2 (setq closure-variables '(wrapper-0 wrapper-1 index miss-fn))))
- (generating-lisp closure-variables
- arglist
- `(let* (,@(unless class-slot-p `((slots nil)))
- (wrapper (cond ((std-instance-p ,instance)
- ,@(unless class-slot-p
- `((setq slots (std-instance-slots ,instance))))
- (std-instance-wrapper ,instance))
- ((fsc-instance-p ,instance)
- ,@(unless class-slot-p
- `((setq slots (fsc-instance-slots ,instance))))
- (fsc-instance-wrapper ,instance)))))
- (block access
- (when (and wrapper
- (/= (wrapper-cache-number-vector-ref wrapper ,field) 0)
- ,@(if (eql 1 1-or-2-class)
- `((eq wrapper wrapper-0))
- `((or (eq wrapper wrapper-0)
- (eq wrapper wrapper-1)))))
- ,@(if readp
- `((let ((value ,read-form))
- (unless (eq value *slot-unbound*)
- (return-from access value))))
- `((return-from access (setf ,read-form ,(car arglist))))))
- (funcall miss-fn ,@arglist))))))
+ (generating-lisp
+ closure-variables
+ arglist
+ `(let* (,@(unless class-slot-p `((slots nil)))
+ (wrapper (cond ((std-instance-p ,instance)
+ ,@(unless class-slot-p
+ `((setq slots
+ (std-instance-slots ,instance))))
+ (std-instance-wrapper ,instance))
+ ((fsc-instance-p ,instance)
+ ,@(unless class-slot-p
+ `((setq slots
+ (fsc-instance-slots ,instance))))
+ (fsc-instance-wrapper ,instance)))))
+ (block access
+ (when (and wrapper
+ (not (zerop (layout-clos-hash wrapper)))
+ ,@(if (eql 1 1-or-2-class)
+ `((eq wrapper wrapper-0))
+ `((or (eq wrapper wrapper-0)
+ (eq wrapper wrapper-1)))))
+ ,@(ecase reader/writer
+ (:reader
+ `((let ((value ,read-form))
+ (unless (eq value +slot-unbound+)
+ (return-from access value)))))
+ (:boundp
+ `((let ((value ,read-form))
+ (return-from access (not (eq value +slot-unbound+))))))
+ (:writer
+ `((return-from access (setf ,read-form ,(car arglist)))))))
+ (funcall miss-fn ,@arglist))))))
(defun emit-slot-read-form (class-slot-p index slots)
(if class-slot-p
`(cdr ,index)
- `(%instance-ref ,slots ,index)))
+ `(clos-slots-ref ,slots ,index)))
(defun emit-boundp-check (value-form miss-fn arglist)
`(let ((value ,value-form))
- (if (eq value *slot-unbound*)
- (funcall ,miss-fn ,@arglist)
- value)))
+ (if (eq value +slot-unbound+)
+ (funcall ,miss-fn ,@arglist)
+ value)))
-(defun emit-slot-access (reader/writer class-slot-p slots index miss-fn arglist)
+(defun emit-slot-access (reader/writer class-slot-p slots
+ index miss-fn arglist)
(let ((read-form (emit-slot-read-form class-slot-p index slots)))
(ecase reader/writer
(:reader (emit-boundp-check read-form miss-fn arglist))
+ (:boundp `(not (eq ,read-form +slot-unbound+)))
(:writer `(setf ,read-form ,(car arglist))))))
(defmacro emit-reader/writer-macro (reader/writer 1-or-2-class class-slot-p)
- (let ((*emit-function-p* nil)
- (*precompiling-lap* t))
+ (let ((*precompiling-lap* t))
(values
(emit-reader/writer reader/writer 1-or-2-class class-slot-p))))
-(defun emit-one-or-n-index-reader/writer (reader/writer cached-index-p class-slot-p)
- (when (and (null *precompiling-lap*) *emit-function-p*)
- (return-from emit-one-or-n-index-reader/writer
- (emit-one-or-n-index-reader/writer-function
- reader/writer cached-index-p class-slot-p)))
+(defun emit-one-or-n-index-reader/writer (reader/writer
+ cached-index-p
+ class-slot-p)
(multiple-value-bind (arglist metatypes)
(ecase reader/writer
- (:reader (values (list (dfun-arg-symbol 0))
- '(standard-instance)))
- (:writer (values (list (dfun-arg-symbol 0) (dfun-arg-symbol 1))
- '(t standard-instance))))
- (generating-lisp `(cache ,@(unless cached-index-p '(index)) miss-fn)
- arglist
- `(let (,@(unless class-slot-p '(slots))
- ,@(when cached-index-p '(index)))
- ,(emit-dlap arglist metatypes
- (emit-slot-access reader/writer class-slot-p
- 'slots 'index 'miss-fn arglist)
- `(funcall miss-fn ,@arglist)
- (when cached-index-p 'index)
- (unless class-slot-p '(slots)))))))
+ ((:reader :boundp)
+ (values (list (dfun-arg-symbol 0))
+ '(standard-instance)))
+ (:writer (values (list (dfun-arg-symbol 0) (dfun-arg-symbol 1))
+ '(t standard-instance))))
+ (generating-lisp
+ `(cache ,@(unless cached-index-p '(index)) miss-fn)
+ arglist
+ `(let (,@(unless class-slot-p '(slots))
+ ,@(when cached-index-p '(index)))
+ ,(emit-dlap 'cache arglist metatypes
+ (emit-slot-access reader/writer class-slot-p
+ 'slots 'index 'miss-fn arglist)
+ `(funcall miss-fn ,@arglist)
+ (when cached-index-p 'index)
+ (unless class-slot-p '(slots)))))))
(defmacro emit-one-or-n-index-reader/writer-macro
(reader/writer cached-index-p class-slot-p)
- (let ((*emit-function-p* nil)
- (*precompiling-lap* t))
+ (let ((*precompiling-lap* t))
(values
- (emit-one-or-n-index-reader/writer reader/writer cached-index-p class-slot-p))))
-
-(defun emit-miss (miss-fn args &optional applyp)
- (let ((restl (when applyp '(.lap-rest-arg.))))
- (if restl
- `(apply ,miss-fn ,@args ,@restl)
- `(funcall ,miss-fn ,@args ,@restl))))
+ (emit-one-or-n-index-reader/writer reader/writer
+ cached-index-p
+ class-slot-p))))
+
+(defun emit-miss (miss-fn args applyp)
+ (if applyp
+ `(multiple-value-call ,miss-fn ,@args
+ (sb-c::%more-arg-values .more-context.
+ 0
+ .more-count.))
+ `(funcall ,miss-fn ,@args)))
(defun emit-checking-or-caching (cached-emf-p return-value-p metatypes applyp)
- (when (and (null *precompiling-lap*) *emit-function-p*)
- (return-from emit-checking-or-caching
- (emit-checking-or-caching-function
- cached-emf-p return-value-p metatypes applyp)))
- (let* ((dlap-lambda-list (make-dlap-lambda-list metatypes applyp))
- (args (remove '&rest dlap-lambda-list))
- (restl (when applyp '(.lap-rest-arg.))))
- (generating-lisp `(cache ,@(unless cached-emf-p '(emf)) miss-fn)
- dlap-lambda-list
- `(let (,@(when cached-emf-p '(emf)))
- ,(emit-dlap args
- metatypes
- (if return-value-p
- (if cached-emf-p 'emf t)
- `(invoke-effective-method-function emf ,applyp
- ,@args ,@restl))
- (emit-miss 'miss-fn args applyp)
- (when cached-emf-p 'emf))))))
-
-(defmacro emit-checking-or-caching-macro (cached-emf-p return-value-p metatypes applyp)
- (let ((*emit-function-p* nil)
- (*precompiling-lap* t))
+ (multiple-value-bind (lambda-list args rest-arg more-arg)
+ (make-dlap-lambda-list (length metatypes) applyp)
+ (generating-lisp
+ `(cache ,@(unless cached-emf-p '(emf)) miss-fn)
+ lambda-list
+ `(let (,@(when cached-emf-p '(emf)))
+ ,(emit-dlap 'cache args metatypes
+ (if return-value-p
+ (if cached-emf-p 'emf t)
+ `(invoke-effective-method-function
+ emf ,applyp
+ :required-args ,args
+ :more-arg ,more-arg
+ :rest-arg ,rest-arg))
+ (emit-miss 'miss-fn args applyp)
+ (when cached-emf-p 'emf))))))
+
+(defmacro emit-checking-or-caching-macro (cached-emf-p
+ return-value-p
+ metatypes
+ applyp)
+ (let ((*precompiling-lap* t))
(values
(emit-checking-or-caching cached-emf-p return-value-p metatypes applyp))))
-(defun emit-dlap (args metatypes hit miss value-reg &optional slot-regs)
+(defun emit-dlap (cache-var args metatypes hit-form miss-form value-var
+ &optional slot-vars)
(let* ((index -1)
- (wrapper-bindings (mapcan #'(lambda (arg mt)
- (unless (eq mt 't)
- (incf index)
- `((,(intern (format nil
- "WRAPPER-~D"
- index)
- *pcl-package*)
- ,(emit-fetch-wrapper mt arg 'miss
- (pop slot-regs))))))
- args metatypes))
- (wrappers (mapcar #'car wrapper-bindings)))
+ (miss-tag (gensym "MISSED"))
+ (wrapper-bindings (mapcan (lambda (arg mt)
+ (unless (eq mt t)
+ (incf index)
+ `((,(format-symbol *pcl-package*
+ "WRAPPER-~D"
+ index)
+ ,(emit-fetch-wrapper
+ mt arg miss-tag (pop slot-vars))))))
+ args metatypes))
+ (wrapper-vars (mapcar #'car wrapper-bindings)))
(declare (fixnum index))
- (unless wrappers (error "Every metatype is T."))
- `(block dfun
- (tagbody
- (let ((field (cache-field cache))
- (cache-vector (cache-vector cache))
- (mask (cache-mask cache))
- (size (cache-size cache))
- (overflow (cache-overflow cache))
- ,@wrapper-bindings)
- (declare (fixnum size field mask))
- ,(cond ((cdr wrappers)
- (emit-greater-than-1-dlap wrappers 'miss value-reg))
- (value-reg
- (emit-1-t-dlap (car wrappers) 'miss value-reg))
- (t
- (emit-1-nil-dlap (car wrappers) 'miss)))
- (return-from dfun ,hit))
- miss
- (return-from dfun ,miss)))))
-
-(defun emit-1-nil-dlap (wrapper miss-label)
- `(let* ((primary ,(emit-1-wrapper-compute-primary-cache-location wrapper miss-label))
- (location primary))
- (declare (fixnum primary location))
- (block search
- (loop (when (eq ,wrapper (cache-vector-ref cache-vector location))
- (return-from search nil))
- (setq location (the fixnum (+ location 1)))
- (when (= location size)
- (setq location 0))
- (when (= location primary)
- (dolist (entry overflow)
- (when (eq (car entry) ,wrapper)
- (return-from search nil)))
- (go ,miss-label))))))
-
-(defmacro get-cache-vector-lock-count (cache-vector)
- `(let ((lock-count (cache-vector-lock-count ,cache-vector)))
- (unless (typep lock-count 'fixnum)
- (error "My cache got freed somehow."))
- (the fixnum lock-count)))
-
-(defun emit-1-t-dlap (wrapper miss-label value)
- `(let ((primary ,(emit-1-wrapper-compute-primary-cache-location wrapper miss-label))
- (initial-lock-count (get-cache-vector-lock-count cache-vector)))
- (declare (fixnum primary initial-lock-count))
- (let ((location primary))
- (declare (fixnum location))
- (block search
- (loop (when (eq ,wrapper (cache-vector-ref cache-vector location))
- (setq ,value (cache-vector-ref cache-vector (1+ location)))
- (return-from search nil))
- (setq location (the fixnum (+ location 2)))
- (when (= location size)
- (setq location 0))
- (when (= location primary)
- (dolist (entry overflow)
- (when (eq (car entry) ,wrapper)
- (setq ,value (cdr entry))
- (return-from search nil)))
- (go ,miss-label))))
- (unless (= initial-lock-count
- (get-cache-vector-lock-count cache-vector))
- (go ,miss-label)))))
-
-(defun emit-greater-than-1-dlap (wrappers miss-label value)
- (declare (type list wrappers))
- (let ((cache-line-size (compute-line-size (+ (length wrappers) (if value 1 0)))))
- `(let ((primary 0) (size-1 (the fixnum (- size 1))))
- (declare (fixnum primary size-1))
- ,(emit-n-wrapper-compute-primary-cache-location wrappers miss-label)
- (let ((initial-lock-count (get-cache-vector-lock-count cache-vector)))
- (declare (fixnum initial-lock-count))
- (let ((location primary) (next-location 0))
- (declare (fixnum location next-location))
- (block search
- (loop (setq next-location (the fixnum (+ location ,cache-line-size)))
- (when (and ,@(mapcar
- #'(lambda (wrapper)
- `(eq ,wrapper
- (cache-vector-ref cache-vector
- (setq location
- (the fixnum (+ location 1))))))
- wrappers))
- ,@(when value
- `((setq location (the fixnum (+ location 1)))
- (setq ,value (cache-vector-ref cache-vector location))))
- (return-from search nil))
- (setq location next-location)
- (when (= location size-1)
- (setq location 0))
- (when (= location primary)
- (dolist (entry overflow)
- (let ((entry-wrappers (car entry)))
- (when (and ,@(mapcar #'(lambda (wrapper)
- `(eq ,wrapper (pop entry-wrappers)))
- wrappers))
- ,@(when value
- `((setq ,value (cdr entry))))
- (return-from search nil))))
- (go ,miss-label))))
- (unless (= initial-lock-count
- (get-cache-vector-lock-count cache-vector))
- (go ,miss-label)))))))
-
-(defun emit-1-wrapper-compute-primary-cache-location (wrapper miss-label)
- `(let ((wrapper-cache-no (wrapper-cache-number-vector-ref ,wrapper field)))
- (declare (fixnum wrapper-cache-no))
- (when (zerop wrapper-cache-no) (go ,miss-label))
- ,(let ((form `(logand mask wrapper-cache-no)))
- `(the fixnum ,form))))
-
-(defun emit-n-wrapper-compute-primary-cache-location (wrappers miss-label)
- (declare (type list wrappers))
- ;; This returns 1 less that the actual location.
- `(progn
- ,@(let ((adds 0) (len (length wrappers)))
- (declare (fixnum adds len))
- (mapcar #'(lambda (wrapper)
- `(let ((wrapper-cache-no (wrapper-cache-number-vector-ref
- ,wrapper field)))
- (declare (fixnum wrapper-cache-no))
- (when (zerop wrapper-cache-no) (go ,miss-label))
- (setq primary (the fixnum (+ primary wrapper-cache-no)))
- ,@(progn
- (incf adds)
- (when (or (zerop (mod adds wrapper-cache-number-adds-ok))
- (eql adds len))
- `((setq primary
- ,(let ((form `(logand primary mask)))
- `(the fixnum ,form))))))))
- wrappers))))
-
-;;; CMU17 (and SBCL) note: Since STD-INSTANCE-P is weakened in the CMU/SBCL
-;;; approach of using funcallable instances, that branch may run
-;;; on non-pcl instances (structures). The result will be the
-;;; non-wrapper layout for the structure, which will cause a miss. The "slots"
-;;; will be whatever the first slot is, but will be ignored. Similarly,
-;;; fsc-instance-p returns true on funcallable structures as well as PCL fins.
-(defun emit-fetch-wrapper (metatype argument miss-label &optional slot)
+ (unless wrapper-vars
+ (error "Every metatype is T."))
+ `(prog ()
+ (return
+ (let ,wrapper-bindings
+ ,(emit-cache-lookup cache-var wrapper-vars miss-tag value-var)
+ ,hit-form))
+ ,miss-tag
+ (return ,miss-form))))
+
+(defun emit-fetch-wrapper (metatype argument miss-tag &optional slot)
(ecase metatype
- ((standard-instance)
- `(cond ((std-instance-p ,argument)
- ,@(when slot `((setq ,slot (std-instance-slots ,argument))))
- (std-instance-wrapper ,argument))
- ((fsc-instance-p ,argument)
- ,@(when slot `((setq ,slot (fsc-instance-slots ,argument))))
- (fsc-instance-wrapper ,argument))
- (t
- (go ,miss-label))))
- (class
- (when slot (error "can't do a slot reg for this metatype"))
- `(wrapper-of-macro ,argument))
- ((built-in-instance structure-instance)
- (when slot (error "can't do a slot reg for this metatype"))
- `(built-in-or-structure-wrapper
- ,argument))))
-
+ ((standard-instance)
+ ;; This branch may run on non-pcl instances (structures). The
+ ;; result will be the non-wrapper layout for the structure, which
+ ;; will cause a miss. Since refencing the structure is rather iffy
+ ;; if it should have no slots, or only raw slots, we use FOR-STD-CLASS-P
+ ;; to ensure that we have a wrapper.
+ ;;
+ ;; FIXME: If we unify layouts and wrappers we can use
+ ;; instance-slots-layout instead of for-std-class-p, as if there
+ ;; are no layouts there are no slots to worry about.
+ (with-unique-names (wrapper)
+ `(cond
+ ((std-instance-p ,argument)
+ (let ((,wrapper (std-instance-wrapper ,argument)))
+ ,@(when slot
+ `((when (layout-for-std-class-p ,wrapper)
+ (setq ,slot (std-instance-slots ,argument)))))
+ ,wrapper))
+ ((fsc-instance-p ,argument)
+ (let ((,wrapper (fsc-instance-wrapper ,argument)))
+ ,@(when slot
+ `((when (layout-for-std-class-p ,wrapper)
+ (setq ,slot (fsc-instance-slots ,argument)))))
+ ,wrapper))
+ (t (go ,miss-tag)))))
+ ;; Sep92 PCL used to distinguish between some of these cases (and
+ ;; spuriously exclude others). Since in SBCL
+ ;; WRAPPER-OF/LAYOUT-OF/BUILT-IN-OR-STRUCTURE-WRAPPER are all
+ ;; equivalent and inlined to each other, we can collapse some
+ ;; spurious differences.
+ ((class built-in-instance structure-instance condition-instance)
+ (when slot
+ (bug "SLOT requested for metatype ~S, but it isnt' going to happen."
+ metatype))
+ `(wrapper-of ,argument))
+ ;; a metatype of NIL should never be seen here, as NIL is only in
+ ;; the metatypes before a generic function is fully initialized.
+ ;; T should never be seen because we never need to get a wrapper
+ ;; to do dispatch if all methods have T as the respective
+ ;; specializer.
+ ((t nil)
+ (bug "~@<metatype ~S seen in ~S.~@:>" metatype 'emit-fetch-wrapper))))