src/code/cross-misc.lisp

   1 ;;;; cross-compile-time-only replacements for miscellaneous unportable
   2 ;;;; stuff
   3
   4 ;;;; This software is part of the SBCL system. See the README file for
   5 ;;;; more information.
   6 ;;;;
   7 ;;;; This software is derived from the CMU CL system, which was
   8 ;;;; written at Carnegie Mellon University and released into the
   9 ;;;; public domain. The software is in the public domain and is
  10 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  11 ;;;; files for more information.
  12
  13 (in-package "SB!IMPL")
  14
  15 ;;; In correct code, TRULY-THE has only a performance impact and can
  16 ;;; be safely degraded to ordinary THE.
  17 (defmacro truly-the (type expr)
  18   `(the ,type ,expr))
  19
  20 (defmacro named-lambda (name args &body body)
  21   (declare (ignore name))
  22   `#'(lambda ,args ,@body))
  23
  24 ;;; Interrupt control isn't an issue in the cross-compiler: we don't
  25 ;;; use address-dependent (and thus GC-dependent) hashes, and we only
  26 ;;; have a single thread of control.
  27 (defmacro without-interrupts (&rest forms)
  28   `(macrolet ((allow-with-interrupts (&body body)
  29                 `(progn ,@body))
  30               (with-local-interrupts (&body body)
  31                 `(progn ,@body)))
  32      ,@forms))
  33
  34 (defmacro with-locked-hash-table ((table) &body body)
  35   (declare (ignore table))
  36   `(progn ,@body))
  37
  38 (defmacro with-locked-system-table ((table) &body body)
  39   (declare (ignore table))
  40   `(progn ,@body))
  41
  42 (defmacro defglobal (name value &rest doc)
  43   `(eval-when (:compile-toplevel :load-toplevel :execute)
  44      (defparameter ,name
  45        (if (boundp ',name)
  46            (symbol-value ',name)
  47            ,value)
  48        ,@doc)))
  49
  50 ;;; The GENESIS function works with fasl code which would, in the
  51 ;;; target SBCL, work on ANSI-STREAMs (streams which aren't extended
  52 ;;; Gray streams). In ANSI Common Lisp, an ANSI-STREAM is just a
  53 ;;; CL:STREAM.
  54 (deftype ansi-stream () 'stream)
  55
  56 (deftype instance ()
  57   '(or condition structure-object standard-object))
  58 (deftype funcallable-instance ()
  59   (error "not clear how to represent FUNCALLABLE-INSTANCE type"))
  60
  61 ;;; In the target SBCL, the INSTANCE type refers to a base
  62 ;;; implementation for compound types with lowtag
  63 ;;; INSTANCE-POINTER-LOWTAG. There's no way to express exactly that
  64 ;;; concept portably, but we can get essentially the same effect by
  65 ;;; testing for any of the standard types which would, in the target
  66 ;;; SBCL, be derived from INSTANCE:
  67 (defun %instancep (x)
  68   (typep x '(or condition structure-object standard-object)))
  69
  70 ;;; There aren't any FUNCALLABLE-INSTANCEs in the cross-compilation
  71 ;;; host Common Lisp.
  72 (defun funcallable-instance-p (x)
  73   (if (typep x 'generic-function)
  74     ;; In the target SBCL, FUNCALLABLE-INSTANCEs are used to implement
  75     ;; generic functions, so any case which tests for this might in
  76     ;; fact be trying to test for generic functions. My (WHN 19990313)
  77     ;; expectation is that this case won't arise in the
  78     ;; cross-compiler, but if it does, it deserves a little thought,
  79     ;; rather than reflexively returning NIL.
  80     (error "not clear how to handle GENERIC-FUNCTION")
  81     nil))
  82
  83 ;;; This seems to be the portable Common Lisp type test which
  84 ;;; corresponds to the effect of the target SBCL implementation test...
  85 (defun array-header-p (x)
  86   (and (typep x 'array)
  87        (or (not (typep x 'simple-array))
  88            (/= (array-rank x) 1))))
  89
  90 (defvar sb!xc:*gensym-counter* 0)
  91
  92 (defun sb!xc:gensym (&optional (thing "G"))
  93   (declare (type string thing))
  94   (let ((n sb!xc:*gensym-counter*))
  95     (prog1
  96         (make-symbol (concatenate 'string thing (write-to-string n :base 10 :radix nil :pretty nil)))
  97       (incf sb!xc:*gensym-counter*))))
  98
  99 ;;; These functions are needed for constant-folding.
 100 (defun simple-array-nil-p (object)
 101   (when (typep object 'array)
 102     (assert (not (eq (array-element-type object) nil))))
 103   nil)
 104
 105 (defun %negate (number)
 106   (- number))
 107
 108 (defun %single-float (number)
 109   (coerce number 'single-float))
 110
 111 (defun %double-float (number)
 112   (coerce number 'double-float))
 113
 114 (defun %ldb (size posn integer)
 115   (ldb (byte size posn) integer))
 116
 117 (defun %dpb (newbyte size posn integer)
 118   (dpb newbyte (byte size posn) integer))
 119
 120 (defun %with-array-data (array start end)
 121   (assert (typep array '(simple-array * (*))))
 122   (values array start end 0))
 123
 124 (defun %with-array-data/fp (array start end)
 125   (assert (typep array '(simple-array * (*))))
 126   (values array start end 0))
 127
 128 (defun signed-byte-32-p (number)
 129   (typep number '(signed-byte 32)))
 130
 131 ;;; package locking nops for the cross-compiler
 132
 133 (defmacro without-package-locks (&body body)
 134   `(progn ,@body))
 135
 136 (defmacro with-single-package-locked-error ((&optional kind thing &rest format)
 137                                             &body body)
 138   (declare (ignore kind thing format))
 139   `(progn ,@body))
 140
 141 (defun program-assert-symbol-home-package-unlocked (context symbol control)
 142   (declare (ignore context control))
 143   symbol)
 144
 145 (defun assert-package-unlocked (package &optional format-control
 146                                 &rest format-arguments)
 147   (declare (ignore format-control format-arguments))
 148   package)
 149
 150 (defun assert-symbol-home-package-unlocked (name &optional format-control
 151                                             &rest format-arguments)
 152   (declare (ignore format-control format-arguments))
 153   name)
 154
 155 (declaim (declaration enable-package-locks disable-package-locks))
 156
 157 ;;; printing structures
 158
 159 (defun default-structure-print (structure stream depth)
 160   (declare (ignore depth))
 161   (write structure :stream stream :circle t))