faster SLOT-VALUE &co with variable slot names
[sbcl.git] / src / pcl / slots-boot.lisp
index dc46d56..36b70d9 100644 (file)
 
 (in-package "SB-PCL")
 \f
-(defun ensure-accessor (type fun-name slot-name)
-  (labels ((slot-missing-fun (slot-name type)
-            (let* ((method-type (ecase type
-                                  (slot-value 'reader-method)
-                                  (setf 'writer-method)
-                                  (slot-boundp 'boundp-method)))
-                   (initargs
-                    (copy-tree
-                     (ecase type
-                       (slot-value
-                        (make-method-function
-                         (lambda (obj)
-                           (values
-                            (slot-missing (class-of obj) obj slot-name
-                                          'slot-value)))))
-                       (slot-boundp
-                        (make-method-function
-                         (lambda (obj)
-                           (not (not
-                                 (slot-missing (class-of obj) obj slot-name
-                                               'slot-boundp))))))
-                       (setf
-                        (make-method-function
-                         (lambda (val obj)
-                           (slot-missing (class-of obj) obj slot-name
-                                         'setf val)
-                           val)))))))
-              (setf (getf (getf initargs :plist) :slot-name-lists)
-                    (list (list nil slot-name)))
-              (setf (getf (getf initargs :plist) :pv-table-symbol)
-                     (gensym))
-              (list* :method-spec (list method-type 'slot-object slot-name)
-                      initargs)))
-          (add-slot-missing-method (gf slot-name type)
-            (multiple-value-bind (class lambda-list specializers)
-                 (ecase type
-                   (slot-value
-                    (values 'standard-reader-method
-                            '(object)
-                            (list *the-class-slot-object*)))
-                   (slot-boundp
-                    (values 'standard-boundp-method
-                            '(object)
-                            (list *the-class-slot-object*)))
-                   (setf
-                    (values 'standard-writer-method
-                            '(new-value object)
-                            (list *the-class-t* *the-class-slot-object*))))
-               (add-method gf (make-a-method class
-                                             ()
-                                             lambda-list
-                                             specializers
-                                             (slot-missing-fun slot-name type)
-                                             "generated slot-missing method"
-                                             slot-name)))))
-        (unless (fboundp fun-name)
-      (let ((gf (ensure-generic-function fun-name)))
-        (ecase type
-          (reader (add-slot-missing-method gf slot-name 'slot-value))
-          (boundp (add-slot-missing-method gf slot-name 'slot-boundp))
-          (writer (add-slot-missing-method gf slot-name 'setf)))
-        (setf (plist-value gf 'slot-missing-method) t))
-      t)))
+(let ((reader-specializers '(slot-object))
+      (writer-specializers '(t slot-object)))
+  (defun ensure-accessor (type fun-name slot-name)
+    (unless (fboundp fun-name)
+      (multiple-value-bind (lambda-list specializers method-class initargs doc)
+          (ecase type
+            ;; FIXME: change SLOT-OBJECT here to T to get SLOT-MISSING
+            ;; behaviour for non-slot-objects too?
+            (reader
+             (values '(object) reader-specializers 'global-reader-method
+                     (make-std-reader-method-function 'slot-object slot-name)
+                     "automatically-generated reader method"))
+            (writer
+             (values '(new-value object) writer-specializers
+                     'global-writer-method
+                     (make-std-writer-method-function 'slot-object slot-name)
+                     "automatically-generated writer method"))
+            (boundp
+             (values '(object) reader-specializers 'global-boundp-method
+                     (make-std-boundp-method-function 'slot-object slot-name)
+                     "automatically-generated boundp method")))
+        (let ((gf (ensure-generic-function fun-name :lambda-list lambda-list)))
+          (add-method gf (make-a-method method-class
+                                        () lambda-list specializers
+                                        initargs doc :slot-name slot-name)))))
+    t)
+  ;; KLUDGE: this is maybe PCL bootstrap mechanism #6 or #7, invented
+  ;; by CSR in June 2007.  Making the bootstrap sane is getting higher
+  ;; on the "TODO: URGENT" list.
+  (defun !fix-ensure-accessor-specializers ()
+    (setf reader-specializers (mapcar #'find-class reader-specializers))
+    (setf writer-specializers (mapcar #'find-class writer-specializers))))
 
-(defmacro accessor-slot-value (object slot-name)
-  (aver (constantp slot-name))
-  (let* ((slot-name (eval slot-name))
-        (reader-name (slot-reader-name slot-name)))
+(defmacro accessor-slot-value (object slot-name &environment env)
+  (aver (constantp slot-name env))
+  (let* ((slot-name (constant-form-value slot-name env))
+         (reader-name (slot-reader-name slot-name)))
     `(let ((.ignore. (load-time-value
-                     (ensure-accessor 'reader ',reader-name ',slot-name))))
+                      (ensure-accessor 'reader ',reader-name ',slot-name))))
       (declare (ignore .ignore.))
-      (funcall #',reader-name ,object))))
+      (truly-the (values t &optional)
+                 (funcall #',reader-name ,object)))))
 
 (defmacro accessor-set-slot-value (object slot-name new-value &environment env)
-  (aver (constantp slot-name))
+  (aver (constantp slot-name env))
   (setq object (macroexpand object env))
-  (setq slot-name (macroexpand slot-name env))
-  (let* ((slot-name (eval slot-name))
-        (bindings (unless (or (constantp new-value) (atom new-value))
-                    (let ((object-var (gensym)))
-                      (prog1 `((,object-var ,object))
-                        (setq object object-var)))))
-        (writer-name (slot-writer-name slot-name))
-        (form
-         `(let ((.ignore.
-                 (load-time-value
-                  (ensure-accessor 'writer ',writer-name ',slot-name)))
-                (.new-value. ,new-value))
-           (declare (ignore .ignore.))
-           (funcall #',writer-name .new-value. ,object)
-           .new-value.)))
-    (if bindings
-       `(let ,bindings ,form)
-       form)))
+  (let* ((slot-name (constant-form-value slot-name env))
+         (bind-object (unless (or (constantp new-value env) (atom new-value))
+                        (let* ((object-var (gensym))
+                               (bind `((,object-var ,object))))
+                          (setf object object-var)
+                          bind)))
+         (writer-name (slot-writer-name slot-name))
+         (form
+          `(let ((.ignore.
+                  (load-time-value
+                   (ensure-accessor 'writer ',writer-name ',slot-name)))
+                 (.new-value. ,new-value))
+            (declare (ignore .ignore.))
+            (funcall #',writer-name .new-value. ,object)
+            .new-value.)))
+    (if bind-object
+        `(let ,bind-object ,form)
+        form)))
 
-(defmacro accessor-slot-boundp (object slot-name)
-  (aver (constantp slot-name))
-  (let* ((slot-name (eval slot-name))
-        (boundp-name (slot-boundp-name slot-name)))
+(defmacro accessor-slot-boundp (object slot-name &environment env)
+  (aver (constantp slot-name env))
+  (let* ((slot-name (constant-form-value slot-name env))
+         (boundp-name (slot-boundp-name slot-name)))
     `(let ((.ignore. (load-time-value
-                     (ensure-accessor 'boundp ',boundp-name ',slot-name))))
+                      (ensure-accessor 'boundp ',boundp-name ',slot-name))))
       (declare (ignore .ignore.))
       (funcall #',boundp-name ,object))))
 
     (declare (ignore object))
     t))
 
+(define-condition instance-structure-protocol-error
+    (reference-condition error)
+  ((slotd :initarg :slotd :reader instance-structure-protocol-error-slotd)
+   (fun :initarg :fun :reader instance-structure-protocol-error-fun))
+  (:report
+   (lambda (c s)
+     (format s "~@<The slot ~S has neither ~S nor ~S ~
+                allocation, so it can't be ~A by the default ~
+                ~S method.~@:>"
+             (instance-structure-protocol-error-slotd c)
+             :instance :class
+             (cond
+               ((member (instance-structure-protocol-error-fun c)
+                        '(slot-value-using-class slot-boundp-using-class))
+                "read")
+               (t "written"))
+             (instance-structure-protocol-error-fun c)))))
+
+(defun instance-structure-protocol-error (slotd fun)
+  (error 'instance-structure-protocol-error
+         :slotd slotd :fun fun
+         :references (list `(:amop :generic-function ,fun)
+                           '(:amop :section (5 5 3)))))
+
 (defun get-optimized-std-accessor-method-function (class slotd name)
   (cond
     ((structure-class-p class)
        (boundp (slot-definition-boundp-function slotd))))
     (t
      (let* ((fsc-p (cond ((standard-class-p class) nil)
-                        ((funcallable-standard-class-p class) t)
-                        ((std-class-p class)
-                         ;; Shouldn't be using the optimized-std-accessors
-                         ;; in this case.
-                         #+nil (format t "* warning: ~S ~S~%   ~S~%"
-                                       name slotd class)
-                         nil)
-                        (t (error "~S is not a STANDARD-CLASS." class))))
-           (slot-name (slot-definition-name slotd))
-           (index (slot-definition-location slotd))
-           (function (ecase name
-                       (reader #'make-optimized-std-reader-method-function)
-                       (writer #'make-optimized-std-writer-method-function)
-                       (boundp #'make-optimized-std-boundp-method-function)))
-           (value (funcall function fsc-p slot-name index)))
+                         ((funcallable-standard-class-p class) t)
+                         ((std-class-p class)
+                          ;; Shouldn't be using the optimized-std-accessors
+                          ;; in this case.
+                          #+nil (format t "* warning: ~S ~S~%   ~S~%"
+                                        name slotd class)
+                          nil)
+                         (t (error "~S is not a STANDARD-CLASS." class))))
+            (slot-name (slot-definition-name slotd))
+            (location (slot-definition-location slotd))
+            (function (ecase name
+                        (reader #'make-optimized-std-reader-method-function)
+                        (writer #'make-optimized-std-writer-method-function)
+                        (boundp #'make-optimized-std-boundp-method-function)))
+            ;; KLUDGE: we need this slightly hacky calling convention
+            ;; for these functions for bootstrapping reasons: see
+            ;; !BOOTSTRAP-MAKE-SLOT-DEFINITION in braid.lisp.  -- CSR,
+            ;; 2004-07-12
+            (value (funcall function fsc-p slotd slot-name location)))
        (declare (type function function))
-       (values value index)))))
+       (values value (slot-definition-location slotd))))))
 
-(defun make-optimized-std-reader-method-function (fsc-p slot-name index)
+(defun make-optimized-std-reader-method-function
+    (fsc-p slotd slot-name location)
   (declare #.*optimize-speed*)
   (set-fun-name
-   (etypecase index
+   (etypecase location
      (fixnum
       (if fsc-p
-         (lambda (instance)
-           (check-obsolete-instance instance)
-           (let ((value (clos-slots-ref (fsc-instance-slots instance) index)))
-             (if (eq value +slot-unbound+)
-                 (values
-                  (slot-unbound (class-of instance) instance slot-name))
-                 value)))
-         (lambda (instance)
-           (check-obsolete-instance instance)
-           (let ((value (clos-slots-ref (std-instance-slots instance) index)))
-             (if (eq value +slot-unbound+)
-                 (values
-                  (slot-unbound (class-of instance) instance slot-name))
-                 value)))))
+          (lambda (instance)
+            (check-obsolete-instance instance)
+            (let ((value (clos-slots-ref (fsc-instance-slots instance)
+                                         location)))
+              (if (eq value +slot-unbound+)
+                  (values
+                   (slot-unbound (class-of instance) instance slot-name))
+                  value)))
+          (lambda (instance)
+            (check-obsolete-instance instance)
+            (let ((value (clos-slots-ref (std-instance-slots instance)
+                                         location)))
+              (if (eq value +slot-unbound+)
+                  (values
+                   (slot-unbound (class-of instance) instance slot-name))
+                  value)))))
      (cons
       (lambda (instance)
-       (check-obsolete-instance instance)
-       (let ((value (cdr index)))
-         (if (eq value +slot-unbound+)
-             (values (slot-unbound (class-of instance) instance slot-name))
-             value)))))
+        (check-obsolete-instance instance)
+        (let ((value (cdr location)))
+          (if (eq value +slot-unbound+)
+              (values (slot-unbound (class-of instance) instance slot-name))
+              value))))
+     (null
+      (lambda (instance)
+        (instance-structure-protocol-error slotd 'slot-value-using-class))))
    `(reader ,slot-name)))
 
-(defun make-optimized-std-writer-method-function (fsc-p slot-name index)
+(defun make-optimized-std-writer-method-function
+    (fsc-p slotd slot-name location)
   (declare #.*optimize-speed*)
-  (set-fun-name
-   (etypecase index
-     (fixnum (if fsc-p
-                (lambda (nv instance)
-                  (check-obsolete-instance instance)
-                  (setf (clos-slots-ref (fsc-instance-slots instance) index)
-                        nv))
-                (lambda (nv instance)
-                  (check-obsolete-instance instance)
-                  (setf (clos-slots-ref (std-instance-slots instance) index)
-                        nv))))
-     (cons   (lambda (nv instance)
-              (check-obsolete-instance instance)
-              (setf (cdr index) nv))))
-   `(writer ,slot-name)))
+  (let* ((safe-p (and slotd
+                      (slot-definition-class slotd)
+                      (safe-p (slot-definition-class slotd))))
+         (writer-fun (etypecase location
+                       (fixnum (if fsc-p
+                                   (lambda (nv instance)
+                                     (check-obsolete-instance instance)
+                                     (setf (clos-slots-ref (fsc-instance-slots instance)
+                                                           location)
+                                           nv))
+                                   (lambda (nv instance)
+                                     (check-obsolete-instance instance)
+                                     (setf (clos-slots-ref (std-instance-slots instance)
+                                                           location)
+                                           nv))))
+                       (cons (lambda (nv instance)
+                               (check-obsolete-instance instance)
+                               (setf (cdr location) nv)))
+                       (null
+                        (lambda (nv instance)
+                          (declare (ignore nv instance))
+                          (instance-structure-protocol-error
+                           slotd
+                           '(setf slot-value-using-class))))))
+         (checking-fun (lambda (new-value instance)
+                         (check-obsolete-instance instance)
+                         ;; If the SLOTD had a TYPE-CHECK-FUNCTION, call it.
+                         (let* (;; Note that this CLASS is not neccessarily
+                                ;; the SLOT-DEFINITION-CLASS of the
+                                ;; SLOTD passed to M-O-S-W-M-F, since it's
+                                ;; e.g. possible for a subclass to define
+                                ;; a slot of the same name but with no
+                                ;; accessors. So we need to fetch the SLOTD
+                                ;; when CHECKING-FUN is called, instead of
+                                ;; just closing over it.
+                                (class (class-of instance))
+                                (slotd (find-slot-definition class slot-name))
+                                (type-check-function
+                                 (when slotd
+                                   (slot-definition-type-check-function slotd))))
+                           (when type-check-function
+                             (funcall type-check-function new-value)))
+                         ;; Then call the real writer.
+                         (funcall writer-fun new-value instance))))
+    (set-fun-name (if safe-p
+                      checking-fun
+                      writer-fun)
+                  `(writer ,slot-name))))
 
-(defun make-optimized-std-boundp-method-function (fsc-p slot-name index)
+(defun make-optimized-std-boundp-method-function
+    (fsc-p slotd slot-name location)
   (declare #.*optimize-speed*)
   (set-fun-name
-   (etypecase index
+   (etypecase location
      (fixnum (if fsc-p
-                (lambda (instance)
-                  (check-obsolete-instance instance)
-                  (not (eq (clos-slots-ref (fsc-instance-slots instance)
-                                           index)
-                           +slot-unbound+)))
-                (lambda (instance)
-                  (check-obsolete-instance instance)
-                  (not (eq (clos-slots-ref (std-instance-slots instance)
-                                           index)
-                           +slot-unbound+)))))
+                 (lambda (instance)
+                   (check-obsolete-instance instance)
+                   (not (eq (clos-slots-ref (fsc-instance-slots instance)
+                                            location)
+                            +slot-unbound+)))
+                 (lambda (instance)
+                   (check-obsolete-instance instance)
+                   (not (eq (clos-slots-ref (std-instance-slots instance)
+                                            location)
+                            +slot-unbound+)))))
      (cons (lambda (instance)
-            (check-obsolete-instance instance)
-            (not (eq (cdr index) +slot-unbound+)))))
+             (check-obsolete-instance instance)
+             (not (eq (cdr location) +slot-unbound+))))
+     (null
+      (lambda (instance)
+        (instance-structure-protocol-error slotd 'slot-boundp-using-class))))
    `(boundp ,slot-name)))
 
-(defun make-optimized-structure-slot-value-using-class-method-function (function)
+(defun make-optimized-structure-slot-value-using-class-method-function
+    (function)
   (declare (type function function))
   (lambda (class object slotd)
     (declare (ignore class slotd))
     (funcall function object)))
 
-(defun make-optimized-structure-setf-slot-value-using-class-method-function (function)
+(defun make-optimized-structure-setf-slot-value-using-class-method-function
+    (function)
   (declare (type function function))
   (lambda (nv class object slotd)
     (declare (ignore class slotd))
     ((structure-class-p class)
      (ecase name
        (reader (make-optimized-structure-slot-value-using-class-method-function
-               (slot-definition-internal-reader-function slotd)))
+                (slot-definition-internal-reader-function slotd)))
        (writer (make-optimized-structure-setf-slot-value-using-class-method-function
-               (slot-definition-internal-writer-function slotd)))
+                (slot-definition-internal-writer-function slotd)))
        (boundp (make-optimized-structure-slot-boundp-using-class-method-function))))
     ((condition-class-p class)
      (ecase name
        (reader
-       (let ((fun (slot-definition-reader-function slotd)))
-         (declare (type function fun))
-         (lambda (class object slotd)
-           (declare (ignore class slotd))
-           (funcall fun object))))
+        (let ((fun (slot-definition-reader-function slotd)))
+          (declare (type function fun))
+          (lambda (class object slotd)
+            (declare (ignore class slotd))
+            (funcall fun object))))
        (writer
-       (let ((fun (slot-definition-writer-function slotd)))
-         (declare (type function fun))
-         (lambda (new-value class object slotd)
-           (declare (ignore class slotd))
-           (funcall fun new-value object))))
+        (let ((fun (slot-definition-writer-function slotd)))
+          (declare (type function fun))
+          (lambda (new-value class object slotd)
+            (declare (ignore class slotd))
+            (funcall fun new-value object))))
        (boundp
-       (let ((fun (slot-definition-boundp-function slotd)))
-         (declare (type function fun))
-         (lambda (class object slotd)
-           (declare (ignore class slotd))
-           (funcall fun object))))))
+        (let ((fun (slot-definition-boundp-function slotd)))
+          (declare (type function fun))
+          (lambda (class object slotd)
+            (declare (ignore class slotd))
+            (funcall fun object))))))
     (t
      (let* ((fsc-p (cond ((standard-class-p class) nil)
-                        ((funcallable-standard-class-p class) t)
-                        (t (error "~S is not a standard-class" class))))
-           (slot-name (slot-definition-name slotd))
-           (index (slot-definition-location slotd))
-           (function
-            (ecase name
-              (reader
-               #'make-optimized-std-slot-value-using-class-method-function)
-              (writer
-               #'make-optimized-std-setf-slot-value-using-class-method-function)
-              (boundp
-               #'make-optimized-std-slot-boundp-using-class-method-function))))
+                         ((funcallable-standard-class-p class) t)
+                         (t (error "~S is not a standard-class" class))))
+            (function
+             (ecase name
+               (reader
+                #'make-optimized-std-slot-value-using-class-method-function)
+               (writer
+                #'make-optimized-std-setf-slot-value-using-class-method-function)
+               (boundp
+                #'make-optimized-std-slot-boundp-using-class-method-function))))
        (declare (type function function))
-       (values (funcall function fsc-p slot-name index) index)))))
+       (values (funcall function fsc-p slotd)
+               (slot-definition-location slotd))))))
 
-(defun make-optimized-std-slot-value-using-class-method-function
-    (fsc-p slot-name index)
+(defun make-optimized-std-slot-value-using-class-method-function (fsc-p slotd)
   (declare #.*optimize-speed*)
-  (etypecase index
-    (fixnum (if fsc-p
-               (lambda (class instance slotd)
-                 (declare (ignore slotd))
-                 (check-obsolete-instance instance)
-                 (let ((value (clos-slots-ref (fsc-instance-slots instance)
-                                              index)))
-                   (if (eq value +slot-unbound+)
-                       (values (slot-unbound class instance slot-name))
-                       value)))
-               (lambda (class instance slotd)
-                 (declare (ignore slotd))
-                 (check-obsolete-instance instance)
-                 (let ((value (clos-slots-ref (std-instance-slots instance)
-                                              index)))
-                   (if (eq value +slot-unbound+)
-                       (values (slot-unbound class instance slot-name))
-                       value)))))
-    (cons   (lambda (class instance slotd)
-             (declare (ignore slotd))
-             (check-obsolete-instance instance)
-             (let ((value (cdr index)))
-               (if (eq value +slot-unbound+)
-                   (values (slot-unbound class instance slot-name))
-                   value))))))
+  (let ((location (slot-definition-location slotd))
+        (slot-name (slot-definition-name slotd)))
+    (etypecase location
+      (fixnum (if fsc-p
+                  (lambda (class instance slotd)
+                    (declare (ignore slotd))
+                    (check-obsolete-instance instance)
+                    (let ((value (clos-slots-ref (fsc-instance-slots instance)
+                                                 location)))
+                      (if (eq value +slot-unbound+)
+                          (values (slot-unbound class instance slot-name))
+                          value)))
+                  (lambda (class instance slotd)
+                    (declare (ignore slotd))
+                    (check-obsolete-instance instance)
+                    (let ((value (clos-slots-ref (std-instance-slots instance)
+                                                 location)))
+                      (if (eq value +slot-unbound+)
+                          (values (slot-unbound class instance slot-name))
+                          value)))))
+      (cons (lambda (class instance slotd)
+              (declare (ignore slotd))
+              (check-obsolete-instance instance)
+              (let ((value (cdr location)))
+                (if (eq value +slot-unbound+)
+                    (values (slot-unbound class instance slot-name))
+                    value))))
+      (null
+       (lambda (class instance slotd)
+         (declare (ignore class instance))
+         (instance-structure-protocol-error slotd 'slot-value-using-class))))))
 
 (defun make-optimized-std-setf-slot-value-using-class-method-function
-    (fsc-p slot-name index)
+    (fsc-p slotd)
   (declare #.*optimize-speed*)
-  (declare (ignore slot-name))
-  (etypecase index
-    (fixnum (if fsc-p
-               (lambda (nv class instance slotd)
-                 (declare (ignore class slotd))
-                 (check-obsolete-instance instance)
-                 (setf (clos-slots-ref (fsc-instance-slots instance) index)
-                       nv))
-               (lambda (nv class instance slotd)
-                 (declare (ignore class slotd))
-                 (check-obsolete-instance instance)
-                 (setf (clos-slots-ref (std-instance-slots instance) index)
-                       nv))))
-    (cons  (lambda (nv class instance slotd)
-            (declare (ignore class slotd))
-            (check-obsolete-instance instance)
-            (setf (cdr index) nv)))))
+  (let ((location (slot-definition-location slotd))
+        (type-check-function
+         (when (and slotd
+                    (slot-definition-class slotd)
+                    (safe-p (slot-definition-class slotd)))
+           (slot-definition-type-check-function slotd))))
+    (macrolet ((make-mf-lambda (&body body)
+                 `(lambda (nv class instance slotd)
+                    (declare (ignore class slotd))
+                    (check-obsolete-instance instance)
+                    ,@body))
+               (make-mf-lambdas (&body body)
+                 ;; Having separate lambdas for the NULL / not-NULL cases of
+                 ;; TYPE-CHECK-FUNCTION is done to avoid runtime overhead
+                 ;; for CLOS typechecking when it's not in use.
+                 `(if type-check-function
+                      (make-mf-lambda
+                       (funcall (the function type-check-function) nv)
+                       ,@body)
+                      (make-mf-lambda
+                       ,@body))))
+      (etypecase location
+        (fixnum
+         (if fsc-p
+             (make-mf-lambdas
+              (setf (clos-slots-ref (fsc-instance-slots instance) location)
+                    nv))
+             (make-mf-lambdas
+              (setf (clos-slots-ref (std-instance-slots instance) location)
+                    nv))))
+        (cons
+         (make-mf-lambdas (setf (cdr location) nv)))
+        (null (lambda (nv class instance slotd)
+                (declare (ignore nv class instance))
+                (instance-structure-protocol-error
+                 slotd '(setf slot-value-using-class))))))))
 
 (defun make-optimized-std-slot-boundp-using-class-method-function
-    (fsc-p slot-name index)
+    (fsc-p slotd)
   (declare #.*optimize-speed*)
-  (declare (ignore slot-name))
-  (etypecase index
-    (fixnum (if fsc-p
-               (lambda (class instance slotd)
-                 (declare (ignore class slotd))
-                 (check-obsolete-instance instance)
-                 (not (eq (clos-slots-ref (fsc-instance-slots instance) index)
-                          +slot-unbound+)))
-               (lambda (class instance slotd)
-                 (declare (ignore class slotd))
-                 (check-obsolete-instance instance)
-                 (not (eq (clos-slots-ref (std-instance-slots instance) index)
-                          +slot-unbound+)))))
-    (cons   (lambda (class instance slotd)
-             (declare (ignore class slotd))
-             (check-obsolete-instance instance)
-             (not (eq (cdr index) +slot-unbound+))))))
+  (let ((location (slot-definition-location slotd)))
+    (etypecase location
+      (fixnum
+       (if fsc-p
+           (lambda (class instance slotd)
+             (declare (ignore class slotd))
+             (check-obsolete-instance instance)
+             (not (eq (clos-slots-ref (fsc-instance-slots instance) location)
+                      +slot-unbound+)))
+           (lambda (class instance slotd)
+             (declare (ignore class slotd))
+             (check-obsolete-instance instance)
+             (not (eq (clos-slots-ref (std-instance-slots instance) location)
+                      +slot-unbound+)))))
+      (cons (lambda (class instance slotd)
+              (declare (ignore class slotd))
+              (check-obsolete-instance instance)
+              (not (eq (cdr location) +slot-unbound+))))
+      (null
+       (lambda (class instance slotd)
+         (declare (ignore class instance))
+         (instance-structure-protocol-error slotd
+                                            'slot-boundp-using-class))))))
 
 (defun get-accessor-from-svuc-method-function (class slotd sdfun name)
   (macrolet ((emf-funcall (emf &rest args)
-              `(invoke-effective-method-function ,emf nil ,@args)))
+               `(invoke-effective-method-function ,emf nil
+                                                  :required-args ,args)))
     (set-fun-name
      (case name
        (reader (lambda (instance)
-                (emf-funcall sdfun class instance slotd)))
+                 (emf-funcall sdfun class instance slotd)))
        (writer (lambda (nv instance)
-                (emf-funcall sdfun nv class instance slotd)))
+                 (emf-funcall sdfun nv class instance slotd)))
        (boundp (lambda (instance)
-                (emf-funcall sdfun class instance slotd))))
+                 (emf-funcall sdfun class instance slotd))))
      `(,name ,(class-name class) ,(slot-definition-name slotd)))))
+\f
+(defun make-std-reader-method-function (class-or-name slot-name)
+  (declare (ignore class-or-name))
+  (let* ((initargs (copy-tree
+                    (make-method-function
+                     (lambda (instance)
+                       (pv-binding1 (.pv. .calls.
+                                          (bug "Please report this")
+                                          (instance) (instance-slots))
+                         (instance-read-internal
+                          .pv. instance-slots 0
+                          (slot-value instance slot-name))))))))
+    (setf (getf (getf initargs 'plist) :slot-name-lists)
+          (list (list nil slot-name)))
+    initargs))
+
+(defun make-std-writer-method-function (class-or-name slot-name)
+  (let* ((class (when (eq *boot-state* 'complete)
+                  (if (typep class-or-name 'class)
+                      class-or-name
+                      (find-class class-or-name nil))))
+         (safe-p (and class
+                      (safe-p class)))
+         (check-fun (lambda (new-value instance)
+                      (let* ((class (class-of instance))
+                             (slotd (find-slot-definition class slot-name))
+                             (type-check-function
+                              (when slotd
+                                (slot-definition-type-check-function slotd))))
+                        (when type-check-function
+                          (funcall type-check-function new-value)))))
+         (initargs (copy-tree
+                    (if safe-p
+                        (make-method-function
+                         (lambda (nv instance)
+                           (funcall check-fun nv instance)
+                           (pv-binding1 (.pv. .calls.
+                                              (bug "Please report this")
+                                              (instance) (instance-slots))
+                             (instance-write-internal
+                              .pv. instance-slots 0 nv
+                              (setf (slot-value instance slot-name) nv)))))
+                        (make-method-function
+                         (lambda (nv instance)
+                           (pv-binding1 (.pv. .calls.
+                                              (bug "Please report this")
+                                              (instance) (instance-slots))
+                             (instance-write-internal
+                              .pv. instance-slots 0 nv
+                              (setf (slot-value instance slot-name) nv)))))))))
+    (setf (getf (getf initargs 'plist) :slot-name-lists)
+          (list nil (list nil slot-name)))
+    initargs))
 
-(defun make-internal-reader-method-function (class-name slot-name)
-  (list* :method-spec `(internal-reader-method ,class-name ,slot-name)
-        (make-method-function
-         (lambda (instance)
-           (let ((wrapper (get-instance-wrapper-or-nil instance)))
-             (if wrapper
-                 (let* ((class (wrapper-class* wrapper))
-                        (index (or (instance-slot-index wrapper slot-name)
-                                   (assq slot-name
-                                         (wrapper-class-slots wrapper)))))
-                   (typecase index
-                     (fixnum   
-                      (let ((value (clos-slots-ref (get-slots instance)
-                                                   index)))
-                        (if (eq value +slot-unbound+)
-                            (values (slot-unbound (class-of instance)
-                                                  instance
-                                                  slot-name))
-                            value)))
-                     (cons
-                      (let ((value (cdr index)))
-                        (if (eq value +slot-unbound+)
-                            (values (slot-unbound (class-of instance)
-                                                  instance
-                                                  slot-name))
-                            value)))
-                     (t
-                      (error "~@<The wrapper for class ~S does not have ~
-                               the slot ~S~@:>"
-                             class slot-name))))
-                 (slot-value instance slot-name)))))))
+(defun make-std-boundp-method-function (class-or-name slot-name)
+  (declare (ignore class-or-name))
+  (let* ((initargs (copy-tree
+                    (make-method-function
+                     (lambda (instance)
+                       (pv-binding1 (.pv. .calls.
+                                          (bug "Please report this")
+                                          (instance) (instance-slots))
+                          (instance-boundp-internal
+                           .pv. instance-slots 0
+                           (slot-boundp instance slot-name))))))))
+    (setf (getf (getf initargs 'plist) :slot-name-lists)
+          (list (list nil slot-name)))
+    initargs))
 \f
-(defun make-std-reader-method-function (class-name slot-name)
-  (let* ((pv-table-symbol (gensym))
-        (initargs (copy-tree
-                   (make-method-function
-                    (lambda (instance)
-                      (pv-binding1 (.pv. .calls.
-                                         (symbol-value pv-table-symbol)
-                                         (instance) (instance-slots))
-                        (instance-read-internal
-                         .pv. instance-slots 1
-                         (slot-value instance slot-name))))))))
-    (setf (getf (getf initargs :plist) :slot-name-lists)
-         (list (list nil slot-name)))
-    (setf (getf (getf initargs :plist) :pv-table-symbol) pv-table-symbol)
-    (list* :method-spec `(reader-method ,class-name ,slot-name)
-          initargs)))
+;;;; FINDING SLOT DEFINITIONS
+;;;
+;;; Historical PCL found slot definitions by iterating over
+;;; CLASS-SLOTS, which is O(N) for number of slots, and moreover
+;;; requires a GF call (for SLOT-DEFINITION-NAME) for each slot in
+;;; list up to the desired one.
+;;;
+;;; Current SBCL hashes the effective slot definitions, and some
+;;; information pulled out from them into a simple-vector, with bucket
+;;; chains made out of plists keyed by the slot names. This fixes
+;;; gives O(1) performance, and avoid the GF calls.
+;;;
+;;; MAKE-SLOT-VECTOR constructs the hashed vector out of a list of
+;;; effective slot definitions and the class they pertain to, and
+;;; FIND-SLOT-DEFINITION knows how to look up slots in that vector.
+;;;
+;;; The only bit of cleverness in the implementation is to make the
+;;; vectors fairly tight, but always longer then 0 elements:
+;;;
+;;; -- We don't want to waste huge amounts of space no these vectors,
+;;;    which are mostly required by things like SLOT-VALUE with a
+;;;    variable slot name, so a constant extension over the minimum
+;;;    size seems like a good choise.
+;;;
+;;; -- As long as the vector always has a length > 0
+;;;    FIND-SLOT-DEFINITION doesn't need to handle the rare case of an
+;;;    empty vector separately: it just returns a NIL.
+;;;
+;;; In addition to the slot-definition we also store the slot-location
+;;; and type-check function for instances of standard metaclasses, so
+;;; that SLOT-VALUE &co using variable slot names can get at them
+;;; without additional GF calls.
+;;;
+;;; Notes:
+;;;   It would be probably better to store the vector in wrapper
+;;;   instead: one less memory indirection, one less CLOS slot
+;;;   access to get at it.
+;;;
+;;;   It would also be nice to have STANDARD-INSTANCE-STRUCTURE-P
+;;;   generic instead of checking versus STANDARD-CLASS and
+;;;   FUNCALLABLE-STANDARD-CLASS.
 
-(defun make-std-writer-method-function (class-name slot-name)
-  (let* ((pv-table-symbol (gensym))
-        (initargs (copy-tree
-                   (make-method-function
-                    (lambda (nv instance)
-                      (pv-binding1 (.pv. .calls.
-                                         (symbol-value pv-table-symbol)
-                                         (instance) (instance-slots))
-                        (instance-write-internal
-                         .pv. instance-slots 1 nv
-                         (setf (slot-value instance slot-name) nv))))))))
-    (setf (getf (getf initargs :plist) :slot-name-lists)
-         (list nil (list nil slot-name)))
-    (setf (getf (getf initargs :plist) :pv-table-symbol) pv-table-symbol)
-    (list* :method-spec `(writer-method ,class-name ,slot-name)
-          initargs)))
+(defun find-slot-definition (class slot-name)
+  (declare (symbol slot-name))
+  (let* ((vector (class-slot-vector class))
+         (index (rem (sxhash slot-name) (length vector))))
+    (declare (simple-vector vector) (index index)
+             (optimize (sb-c::insert-array-bounds-checks 0)))
+    (do ((plist (the list (svref vector index)) (cdr plist)))
+        ((not (consp plist)))
+      (let ((key (car plist)))
+        (setf plist (cdr plist))
+        (when (eq key slot-name)
+          (return (cddar plist)))))))
 
-(defun make-std-boundp-method-function (class-name slot-name)
-  (let* ((pv-table-symbol (gensym))
-        (initargs (copy-tree
-                   (make-method-function
-                    (lambda (instance)
-                      (pv-binding1 (.pv. .calls.
-                                         (symbol-value pv-table-symbol)
-                                         (instance) (instance-slots))
-                         (instance-boundp-internal
-                          .pv. instance-slots 1
-                          (slot-boundp instance slot-name))))))))
-    (setf (getf (getf initargs :plist) :slot-name-lists)
-         (list (list nil slot-name)))
-    (setf (getf (getf initargs :plist) :pv-table-symbol) pv-table-symbol)
-    (list* :method-spec `(boundp-method ,class-name ,slot-name)
-          initargs)))
+(defun find-slot-cell (class slot-name)
+  (declare (symbol slot-name))
+  (let* ((vector (class-slot-vector class))
+         (index (rem (sxhash slot-name) (length vector))))
+    (declare (simple-vector vector) (index index)
+             (optimize (sb-c::insert-array-bounds-checks 0)))
+    (do ((plist (the list (svref vector index)) (cdr plist)))
+        ((not (consp plist)))
+      (let ((key (car plist)))
+        (setf plist (cdr plist))
+        (when (eq key slot-name)
+          (return (car plist)))))))
 
-(defun initialize-internal-slot-gfs (slot-name &optional type)
-  (macrolet ((frob (type name-fun add-fun)
-              `(when (or (null type) (eq type ',type))
-                (let* ((name (,name-fun slot-name))
-                       (gf (ensure-generic-function name))
-                       (methods (generic-function-methods gf)))
-                  (when (or (null methods)
-                            (plist-value gf 'slot-missing-method))
-                    (setf (plist-value gf 'slot-missing-method) nil)
-                    (,add-fun *the-class-slot-object* gf slot-name))))))
-    (frob reader slot-reader-name add-reader-method)
-    (frob writer slot-writer-name add-writer-method)
-    (frob boundp slot-boundp-name add-boundp-method)))
+(defun make-slot-vector (class slots)
+  (let* ((n (+ (length slots) 2))
+         (vector (make-array n :initial-element nil))
+         (save-slot-location-p
+          (when (eq 'complete *boot-state*)
+            (let ((metaclass (class-of class)))
+              (or (eq metaclass *the-class-standard-class*)
+                  (eq metaclass *the-class-funcallable-standard-class*)))))
+         (save-type-check-function-p (and save-slot-location-p (safe-p class))))
+    (flet ((add-to-vector (name slot)
+             (declare (symbol name)
+                      (optimize (sb-c::insert-array-bounds-checks 0)))
+             (let ((index (rem (sxhash name) n)))
+               (setf (svref vector index)
+                     (list* name (list* (if save-slot-location-p
+                                            (slot-definition-location slot)
+                                            ;; T tells SLOT-VALUE & SET-SLOT-VALUE
+                                            ;; that this is a non-standard class.
+                                            t)
+                                        (when save-type-check-function-p
+                                          (slot-definition-type-check-function slot))
+                                        slot)
+                            (svref vector index))))))
+      (if (eq 'complete *boot-state*)
+         (dolist (slot slots)
+           (add-to-vector (slot-definition-name slot) slot))
+         (dolist (slot slots)
+           (add-to-vector (early-slot-definition-name slot) slot))))
+    vector))