0.7.5.11:
[sbcl.git] / src / pcl / boot.lisp
index 3284897..6f4177c 100644 (file)
@@ -702,10 +702,10 @@ bootstrapping.
                                          rest-arg
                                          &rest lmf-options)
                                         &body body)
- `(bind-fast-lexical-method-macros (,args ,rest-arg ,next-method-call)
-    (bind-lexical-method-functions (,@lmf-options)
-      (bind-args (,(nthcdr (length args) lambda-list) ,rest-arg)
-       ,@body))))
+  `(bind-fast-lexical-method-macros (,args ,rest-arg ,next-method-call)
+     (bind-lexical-method-functions (,@lmf-options)
+       (bind-args (,(nthcdr (length args) lambda-list) ,rest-arg)
+        ,@body))))
 
 (defmacro bind-simple-lexical-method-macros ((method-args next-methods)
                                             &body body)
@@ -770,11 +770,8 @@ bootstrapping.
 #-sb-fluid (declaim (sb-ext:freeze-type fast-instance-boundp))
 
 (eval-when (:compile-toplevel :load-toplevel :execute)
-
-(defvar *allow-emf-call-tracing-p* nil)
-(defvar *enable-emf-call-tracing-p* #-testing nil #+testing t)
-
-) ; EVAL-WHEN
+  (defvar *allow-emf-call-tracing-p* nil)
+  (defvar *enable-emf-call-tracing-p* #-sb-show nil #+sb-show t))
 \f
 ;;;; effective method functions
 
@@ -824,26 +821,25 @@ bootstrapping.
                                                &rest required-args+rest-arg)
   (unless (constantp restp)
     (error "The RESTP argument is not constant."))
+  ;; FIXME: The RESTP handling here is confusing and maybe slightly
+  ;; broken if RESTP evaluates to a non-self-evaluating form. E.g. if
+  ;;   (INVOKE-EFFECTIVE-METHOD-FUNCTION EMF '(ERROR "gotcha") ...)
+  ;; then TRACE-EMF-CALL-CALL-INTERNAL might die on a gotcha error.
   (setq restp (eval restp))
-  `(locally
-
-     ;; In sbcl-0.6.11.43, the compiler would issue bogus warnings
-     ;; about type mismatches in unreachable code when we
-     ;; macroexpanded the GET-SLOTS-OR-NIL expressions here and
-     ;; byte-compiled the code. GET-SLOTS-OR-NIL is now an inline
-     ;; function instead of a macro, which seems sufficient to solve
-     ;; the problem all by itself (probably because of some quirk in
-     ;; the relative order of expansion and type inference) but we
-     ;; also use overkill by NOTINLINEing GET-SLOTS-OR-NIL, because it
-     ;; looks as though (1) inlining isn't that much of a win anyway,
-     ;; and (2a) once you miss the FAST-METHOD-CALL clause you're
-     ;; going to be slow anyway, but (2b) code bloat still hurts even
-     ;; when it's off the critical path.
-     (declare (notinline get-slots-or-nil))
-
+  `(progn
      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
      (cond ((typep ,emf 'fast-method-call)
-            (invoke-fast-method-call ,emf ,@required-args+rest-arg))
+           (invoke-fast-method-call ,emf ,@required-args+rest-arg))
+          ;; "What," you may wonder, "do these next two clauses do?"
+          ;; In that case, you are not a PCL implementor, for they
+          ;; considered this to be self-documenting.:-| Or CSR, for
+          ;; that matter, since he can also figure it out by looking
+          ;; at it without breaking stride. For the rest of us,
+          ;; though: From what the code is doing with .SLOTS. and
+          ;; whatnot, evidently it's implementing SLOT-VALUEish and
+          ;; GET-SLOT-VALUEish things. Then we can reason backwards
+          ;; and conclude that setting EMF to a FIXNUM is an
+          ;; optimized way to represent these slot access operations.
           ,@(when (and (null restp) (= 1 (length required-args+rest-arg)))
               `(((typep ,emf 'fixnum)
                  (let* ((.slots. (get-slots-or-nil
@@ -858,18 +854,12 @@ bootstrapping.
                  (let ((.new-value. ,(car required-args+rest-arg))
                        (.slots. (get-slots-or-nil
                                  ,(car required-args+rest-arg))))
-                    (when .slots.
-                         (setf (clos-slots-ref .slots. ,emf) .new-value.))))))
-          #||
-          ,@(when (and (null restp) (= 1 (length required-args+rest-arg)))
-              `(((typep ,emf 'fast-instance-boundp)
-                 (let ((.slots. (get-slots-or-nil
-                                 ,(car required-args+rest-arg))))
-                   (and .slots.
-                        (not (eq (clos-slots-ref
-                                  .slots. (fast-instance-boundp-index ,emf))
-                                 +slot-unbound+)))))))
-          ||#
+                   (when .slots.
+                     (setf (clos-slots-ref .slots. ,emf) .new-value.))))))
+          ;; (In cmucl-2.4.8 there was a commented-out third ,@(WHEN
+          ;; ...) clause here to handle SLOT-BOUNDish stuff. Since
+          ;; there was no explanation and presumably the code is 10+
+          ;; years stale, I simply deleted it. -- WHN)
           (t
            (etypecase ,emf
              (method-call
@@ -963,7 +953,32 @@ bootstrapping.
 \f
 (defmacro bind-fast-lexical-method-macros ((args rest-arg next-method-call)
                                           &body body)
-  `(macrolet ((call-next-method-bind (&body body)
+  `(macrolet ((narrowed-emf (emf)
+               ;; INVOKE-EFFECTIVE-METHOD-FUNCTION has code in it to
+               ;; dispatch on the possibility that EMF might be of
+               ;; type FIXNUM (as an optimized representation of a
+               ;; slot accessor). But as far as I (WHN 2002-06-11)
+               ;; can tell, it's impossible for such a representation
+               ;; to end up as .NEXT-METHOD-CALL. By reassuring
+               ;; INVOKE-E-M-F that when called from this context
+               ;; it needn't worry about the FIXNUM case, we can
+               ;; keep those cases from being compiled, which is
+               ;; good both because it saves bytes and because it
+               ;; avoids annoying type mismatch compiler warnings.
+               ;;
+                ;; KLUDGE: In sbcl-0.7.4.29, the compiler's type
+               ;; system isn't smart enough about NOT and intersection
+               ;; types to benefit from a (NOT FIXNUM) declaration
+               ;; here. -- WHN 2002-06-12
+               ;;
+               ;; FIXME: Might the FUNCTION type be omittable here,
+               ;; leaving only METHOD-CALLs? Failing that, could this
+               ;; be documented somehow? (It'd be nice if the types
+               ;; involved could be understood without solving the
+                ;; halting problem.)
+                `(the (or function method-call fast-method-call)
+                  ,emf))
+             (call-next-method-bind (&body body)
                `(let () ,@body))
              (call-next-method-body (cnm-args)
                `(if ,',next-method-call
@@ -978,17 +993,18 @@ bootstrapping.
                             (consp cnm-args)
                             (eq (car cnm-args) 'list))
                        `(invoke-effective-method-function
-                         ,',next-method-call nil
+                         (narrowed-emf ,',next-method-call)
+                        nil
                          ,@(cdr cnm-args))
                        (let ((call `(invoke-effective-method-function
-                                     ,',next-method-call
+                                     (narrowed-emf ,',next-method-call)
                                      ,',(not (null rest-arg))
                                      ,@',args
                                      ,@',(when rest-arg `(,rest-arg)))))
                          `(if ,cnm-args
                            (bind-args ((,@',args
                                         ,@',(when rest-arg
-                                                  `(&rest ,rest-arg)))
+                                             `(&rest ,rest-arg)))
                                        ,cnm-args)
                             ,call)
                            ,call))))