src/pcl/compiler-support.lisp

   1 ;;;; things which the main SBCL compiler needs to know about the
   2 ;;;; implementation of CLOS
   3 ;;;;
   4 ;;;; (Our CLOS is derived from PCL, which was implemented in terms of
   5 ;;;; portable high-level Common Lisp. But now that it no longer needs
   6 ;;;; to be portable, we can make some special hacks to support it
   7 ;;;; better.)
   8
   9 ;;;; This software is part of the SBCL system. See the README file for more
  10 ;;;; information.
  11
  12 ;;;; This software is derived from software originally released by Xerox
  13 ;;;; Corporation. Copyright and release statements follow. Later modifications
  14 ;;;; to the software are in the public domain and are provided with
  15 ;;;; absolutely no warranty. See the COPYING and CREDITS files for more
  16 ;;;; information.
  17
  18 ;;;; copyright information from original PCL sources:
  19 ;;;;
  20 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
  21 ;;;; All rights reserved.
  22 ;;;;
  23 ;;;; Use and copying of this software and preparation of derivative works based
  24 ;;;; upon this software are permitted. Any distribution of this software or
  25 ;;;; derivative works must comply with all applicable United States export
  26 ;;;; control laws.
  27 ;;;;
  28 ;;;; This software is made available AS IS, and Xerox Corporation makes no
  29 ;;;; warranty about the software, its performance or its conformity to any
  30 ;;;; specification.
  31
  32 (in-package "SB-C")
  33 \f
  34 ;;;; very low-level representation of instances with meta-class
  35 ;;;; STANDARD-CLASS
  36
  37 (defknown sb-pcl::pcl-instance-p (t) boolean
  38   (movable foldable flushable explicit-check))
  39
  40 (deftransform sb-pcl::pcl-instance-p ((object))
  41   (let* ((otype (lvar-type object))
  42          (standard-object (specifier-type 'standard-object)))
  43     (cond
  44       ;; Flush tests whose result is known at compile time.
  45       ((csubtypep otype standard-object) t)
  46       ((not (types-equal-or-intersect otype standard-object)) nil)
  47       (t
  48        `(layout-for-std-class-p (layout-of object))))))
  49
  50 (defun sb-pcl::safe-code-p (&optional env)
  51   (let* ((lexenv (or env (make-null-lexenv)))
  52          (policy (lexenv-policy lexenv)))
  53     (eql (cdr (assoc 'safety policy)) 3)))
  54
  55 (declaim (ftype function sb-pcl::parse-specialized-lambda-list))
  56 (define-source-context defmethod (name &rest stuff)
  57   (let ((arg-pos (position-if #'listp stuff)))
  58     (if arg-pos
  59         `(defmethod ,name ,@(subseq stuff 0 arg-pos)
  60            ,(handler-case
  61                 (nth-value 2 (sb-pcl::parse-specialized-lambda-list
  62                               (elt stuff arg-pos)))
  63               (error () "<illegal syntax>")))
  64         `(defmethod ,name "<illegal syntax>"))))
  65
  66 (defvar sb-pcl::*internal-pcl-generalized-fun-name-symbols* nil)
  67
  68 (defmacro define-internal-pcl-function-name-syntax (name (var) &body body)
  69   `(progn
  70      (define-function-name-syntax ,name (,var) ,@body)
  71      (pushnew ',name sb-pcl::*internal-pcl-generalized-fun-name-symbols*)))
  72
  73 (define-internal-pcl-function-name-syntax sb-pcl::slot-accessor (list)
  74   (when (= (length list) 4)
  75     (destructuring-bind (class slot rwb) (cdr list)
  76       (when (and (member rwb '(sb-pcl::reader sb-pcl::writer sb-pcl::boundp))
  77                  (symbolp slot)
  78                  (symbolp class))
  79         (values t slot)))))
  80
  81 (define-internal-pcl-function-name-syntax sb-pcl::fast-method (list)
  82   (valid-function-name-p (cadr list)))
  83
  84 (define-internal-pcl-function-name-syntax sb-pcl::slow-method (list)
  85   (valid-function-name-p (cadr list)))
  86
  87 (declaim (ftype function sb-pcl::std-instance-p sb-pcl::fsc-instance-p))
  88 (define-internal-pcl-function-name-syntax sb-pcl::ctor (list)
  89   (let ((class-or-name (cadr list)))
  90     (cond
  91       ((symbolp class-or-name)
  92        (values (valid-function-name-p class-or-name) nil))
  93       ((or (sb-pcl::std-instance-p class-or-name)
  94            (sb-pcl::fsc-instance-p class-or-name))
  95        (values t nil)))))
  96