src/code/kernel.lisp

   1 ;;;; miscellaneous kernel-level definitions
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; This software is derived from the CMU CL system, which was
   7 ;;;; written at Carnegie Mellon University and released into the
   8 ;;;; public domain. The software is in the public domain and is
   9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  10 ;;;; files for more information.
  11
  12 (in-package "SB!KERNEL")
  13
  14 ;;; Return the 24 bits of data in the header of object X, which must
  15 ;;; be an other-pointer object.
  16 (defun get-header-data (x)
  17   (get-header-data x))
  18
  19 ;;; Set the 24 bits of data in the header of object X (which must be
  20 ;;; an other-pointer object) to VAL.
  21 (defun set-header-data (x val)
  22   (set-header-data x val))
  23
  24 ;;; Return the 24 bits of data in the header of object X, which must
  25 ;;; be a fun-pointer object.
  26 ;;;
  27 ;;; FIXME: Should this not be called GET-FUN-LENGTH instead? Or even better
  28 ;;; yet, if GET-HEADER-DATA masked the lowtag instead of substracting it, we
  29 ;;; could just use it instead -- or at least this could just be a function on
  30 ;;; top of the same VOP.
  31 (defun get-closure-length (x)
  32   (get-closure-length x))
  33
  34 (defun lowtag-of (x)
  35   (lowtag-of x))
  36
  37 (defun widetag-of (x)
  38   (widetag-of x))
  39
  40 ;;; WIDETAG-OF needs extra code to handle LIST and FUNCTION lowtags. When
  41 ;;; we're only dealing with other pointers (eg. when dispatching on array
  42 ;;; element type), this is going to be faster.
  43 (declaim (inline %other-pointer-widetag))
  44 (defun %other-pointer-widetag (x)
  45   (sb!sys:sap-ref-8 (int-sap (get-lisp-obj-address x))
  46                     #.(ecase sb!c:*backend-byte-order*
  47                         (:little-endian
  48                          (- sb!vm:other-pointer-lowtag))
  49                         (:big-endian
  50                          (- (1- sb!vm:n-word-bytes) sb!vm:other-pointer-lowtag)))))
  51
  52 ;;; Return a System-Area-Pointer pointing to the data for the vector
  53 ;;; X, which must be simple.
  54 ;;;
  55 ;;; FIXME: So it should be SIMPLE-VECTOR-SAP, right? (or UNHAIRY-VECTOR-SAP,
  56 ;;; if the meaning is (SIMPLE-ARRAY * 1) instead of SIMPLE-VECTOR)
  57 ;;; (or maybe SIMPLE-VECTOR-DATA-SAP or UNHAIRY-VECTOR-DATA-SAP?)
  58 (defun vector-sap (x)
  59   (declare (type (simple-unboxed-array (*)) x))
  60   (vector-sap x))
  61
  62 ;;; Return a System-Area-Pointer pointing to the end of the binding stack.
  63 (defun sb!c::binding-stack-pointer-sap ()
  64   (sb!c::binding-stack-pointer-sap))
  65
  66 ;;; Return a System-Area-Pointer pointing to the next free word of the
  67 ;;; current dynamic space.
  68 (defun sb!c::dynamic-space-free-pointer ()
  69   (sb!c::dynamic-space-free-pointer))
  70
  71 ;;; Return a System-Area-Pointer pointing to the end of the control stack.
  72 (defun sb!c::control-stack-pointer-sap ()
  73   (sb!c::control-stack-pointer-sap))
  74
  75 ;;; Return the header typecode for FUNCTION. Can be set with SETF.
  76 (defun fun-subtype (function)
  77   (fun-subtype function))
  78 (defun (setf fun-subtype) (type function)
  79   (setf (fun-subtype function) type))
  80
  81 ;;;; SIMPLE-FUN and accessors
  82
  83 (defun simple-fun-p (object)
  84   (simple-fun-p object))
  85
  86 (deftype simple-fun ()
  87   '(satisfies simple-fun-p))
  88
  89 (defun %simple-fun-doc (simple-fun)
  90   (declare (simple-fun simple-fun))
  91   (let ((info (%simple-fun-info simple-fun)))
  92     (cond ((typep info '(or null string))
  93            info)
  94           ((simple-vector-p info)
  95            nil)
  96           ((consp info)
  97            (car info))
  98           (t
  99            (bug "bogus INFO for ~S: ~S" simple-fun info)))))
 100
 101 (defun (setf %simple-fun-doc) (doc simple-fun)
 102   (declare (type (or null string) doc)
 103            (simple-fun simple-fun))
 104   (let ((info (%simple-fun-info simple-fun)))
 105     (setf (%simple-fun-info simple-fun)
 106           (cond ((typep info '(or null string))
 107                  doc)
 108                 ((simple-vector-p info)
 109                  (if doc
 110                      (cons doc info)
 111                      info))
 112                 ((consp info)
 113                  (if doc
 114                      (cons doc (cdr info))
 115                      (cdr info)))
 116                 (t
 117                  (bug "bogus INFO for ~S: ~S" simple-fun info))))))
 118
 119 (defun %simple-fun-xrefs (simple-fun)
 120   (declare (simple-fun simple-fun))
 121   (let ((info (%simple-fun-info simple-fun)))
 122     (cond ((typep info '(or null string))
 123            nil)
 124           ((simple-vector-p info)
 125            info)
 126           ((consp info)
 127            (cdr info))
 128           (t
 129            (bug "bogus INFO for ~S: ~S" simple-fun info)))))
 130
 131 ;;; Extract the arglist from the function header FUNC.
 132 (defun %simple-fun-arglist (func)
 133   (%simple-fun-arglist func))
 134
 135 (defun (setf %simple-fun-arglist) (new-value func)
 136   (setf (%simple-fun-arglist func) new-value))
 137
 138 ;;; Extract the name from the function header FUNC.
 139 (defun %simple-fun-name (func)
 140   (%simple-fun-name func))
 141
 142 (defun (setf %simple-fun-name) (new-value func)
 143   (setf (%simple-fun-name func) new-value))
 144
 145 ;;; Extract the type from the function header FUNC.
 146 (defun %simple-fun-type (func)
 147   (%simple-fun-type func))
 148
 149 (defun %simple-fun-next (simple-fun)
 150   (%simple-fun-next simple-fun))
 151
 152 ;; Given either a closure or a simple-fun, return the underlying simple-fun.
 153 ;; FIXME: %SIMPLE-FUN-SELF is a somewhat poor name for this function.
 154 ;; The x86[-64] code defines %CLOSURE-FUN as nothing more than %SIMPLE-FUN-SELF,
 155 ;; and it's not clear whether that's because callers need the "simple" accessor
 156 ;; to work on closures, versus reluctance to define a %CLOSURE/SIMPLE-FUN-FUN
 157 ;; reader. %FUN-FUN works on all three function subtypes, but is nontrivial.
 158 ;; Preferably at least one accessor should get a new name,
 159 ;; so that %SIMPLE-FUN-SELF can mean what it says.
 160
 161 (defun %simple-fun-self (simple-fun)
 162   (%simple-fun-self simple-fun))
 163
 164 ;;;; CLOSURE type and accessors
 165
 166 (defun closurep (object)
 167   (closurep object))
 168
 169 (deftype closure ()
 170   '(satisfies closurep))
 171
 172 (defmacro do-closure-values ((value closure) &body body)
 173   (with-unique-names (i nclosure)
 174     `(let ((,nclosure ,closure))
 175        (declare (closure ,nclosure))
 176        (dotimes (,i (- (1+ (get-closure-length ,nclosure)) sb!vm:closure-info-offset))
 177          (let ((,value (%closure-index-ref ,nclosure ,i)))
 178            ,@body)))))
 179
 180 (defun %closure-values (closure)
 181   (declare (closure closure))
 182   (let (values)
 183     (do-closure-values (elt closure)
 184       (push elt values))
 185     (nreverse values)))
 186
 187 ;;; Extract the function from CLOSURE.
 188 (defun %closure-fun (closure)
 189   (%closure-fun closure))
 190
 191 ;;; Extract the INDEXth slot from CLOSURE.
 192 (defun %closure-index-ref (closure index)
 193   (%closure-index-ref closure index))
 194
 195 ;;; Return the length of VECTOR. There is no reason to use this in
 196 ;;; ordinary code, 'cause length (the vector foo)) is the same.
 197 (defun sb!c::vector-length (vector)
 198   (sb!c::vector-length vector))
 199
 200 ;;; Allocate a unboxed, simple vector with type code TYPE, length LENGTH, and
 201 ;;; WORDS words long. Note: it is your responsibility to ensure that the
 202 ;;; relation between LENGTH and WORDS is correct.
 203 (defun allocate-vector (type length words)
 204   (allocate-vector type length words))
 205
 206 ;;; Allocate an array header with type code TYPE and rank RANK.
 207 (defun make-array-header (type rank)
 208   (make-array-header type rank))
 209
 210 ;;; Return a SAP pointing to the instructions part of CODE-OBJ.
 211 (defun code-instructions (code-obj)
 212   (code-instructions code-obj))
 213
 214 ;;; Extract the INDEXth element from the header of CODE-OBJ. Can be
 215 ;;; set with SETF.
 216 (defun code-header-ref (code-obj index)
 217   (code-header-ref code-obj index))
 218
 219 (defun code-header-set (code-obj index new)
 220   (code-header-set code-obj index new))
 221
 222 (defun %vector-raw-bits (object offset)
 223   (declare (type index offset))
 224   (%vector-raw-bits object offset))
 225
 226 (defun %set-vector-raw-bits (object offset value)
 227   (declare (type index offset))
 228   (declare (type word value))
 229   (setf (%vector-raw-bits object offset) value))
 230
 231 (defun make-single-float (x) (make-single-float x))
 232 (defun make-double-float (hi lo) (make-double-float hi lo))
 233
 234 (defun single-float-bits (x) (single-float-bits x))
 235 (defun double-float-high-bits (x) (double-float-high-bits x))
 236 (defun double-float-low-bits (x) (double-float-low-bits x))
 237