src/compiler/generic/objdef.lisp

   1 ;;;; machine-independent aspects of the object representation
   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!VM")
  13
  14 ;;;; KLUDGE: The primitive objects here may look like self-contained
  15 ;;;; definitions, but in general they're not. In particular, if you
  16 ;;;; try to add a slot to them, beware of the following:
  17 ;;;;   * (mysterious crashes which occur after changing the length
  18 ;;;;     of SIMPLE-FUN, just adding a new slot not even doing anything
  19 ;;;;     with it, still dunno why)
  20 ;;;;   * The GC scavenging code (and for all I know other GC code too)
  21 ;;;;     is not automatically generated from these layouts, but instead
  22 ;;;;     was hand-written to correspond to them. The offsets are
  23 ;;;;     automatically propagated into the GC scavenging code, but the
  24 ;;;;     existence of slots, and whether they should be scavenged, is
  25 ;;;;     not automatically propagated. Thus e.g. if you add a
  26 ;;;;     SIMPLE-FUN-DEBUG-INFO slot holding a tagged object which needs
  27 ;;;;     to be GCed, you need to tweak scav_code_header() and
  28 ;;;;     verify_space() in gencgc.c, and the corresponding code in gc.c.
  29 ;;;;   * The src/runtime/print.c code (used by LDB) is implemented
  30 ;;;;     using hand-written lists of slot names, which aren't automatically
  31 ;;;;     generated from the code in this file.
  32 ;;;;   * Various code (e.g. STATIC-FSET in genesis.lisp) is hard-wired
  33 ;;;;     to know the name of the last slot of the object the code works
  34 ;;;;     with, and implicitly to know that the last slot is special (being
  35 ;;;;     the beginning of an arbitrary-length sequence of bytes following
  36 ;;;;     the fixed-layout slots).
  37 ;;;; -- WHN 2001-12-29
  38 \f
  39 ;;;; the primitive objects themselves
  40
  41 (define-primitive-object (cons :lowtag list-pointer-lowtag
  42                                :alloc-trans cons)
  43   (car :ref-trans car :set-trans sb!c::%rplaca :init :arg
  44        :cas-trans %compare-and-swap-car)
  45   (cdr :ref-trans cdr :set-trans sb!c::%rplacd :init :arg
  46        :cas-trans %compare-and-swap-cdr))
  47
  48 (define-primitive-object (instance :lowtag instance-pointer-lowtag
  49                                    :widetag instance-header-widetag
  50                                    :alloc-trans %make-instance)
  51   (slots :rest-p t))
  52
  53 (define-primitive-object (bignum :lowtag other-pointer-lowtag
  54                                  :widetag bignum-widetag
  55                                  :alloc-trans sb!bignum::%allocate-bignum)
  56   (digits :rest-p t :c-type #!-alpha "long" #!+alpha "u32"))
  57
  58 (define-primitive-object (ratio :type ratio
  59                                 :lowtag other-pointer-lowtag
  60                                 :widetag ratio-widetag
  61                                 :alloc-trans %make-ratio)
  62   (numerator :type integer
  63              :ref-known (flushable movable)
  64              :ref-trans %numerator
  65              :init :arg)
  66   (denominator :type integer
  67                :ref-known (flushable movable)
  68                :ref-trans %denominator
  69                :init :arg))
  70
  71 #!+#.(cl:if (cl:= sb!vm:n-word-bits 32) '(and) '(or))
  72 (define-primitive-object (single-float :lowtag other-pointer-lowtag
  73                                        :widetag single-float-widetag)
  74   (value :c-type "float"))
  75
  76 (define-primitive-object (double-float :lowtag other-pointer-lowtag
  77                                        :widetag double-float-widetag)
  78   #!-x86-64 (filler)
  79   (value :c-type "double" :length #!-x86-64 2 #!+x86-64 1))
  80
  81 #!+long-float
  82 (define-primitive-object (long-float :lowtag other-pointer-lowtag
  83                                      :widetag long-float-widetag)
  84   #!+sparc (filler)
  85   (value :c-type "long double" :length #!+x86 3 #!+sparc 4))
  86
  87 (define-primitive-object (complex :type complex
  88                                   :lowtag other-pointer-lowtag
  89                                   :widetag complex-widetag
  90                                   :alloc-trans %make-complex)
  91   (real :type real
  92         :ref-known (flushable movable)
  93         :ref-trans %realpart
  94         :init :arg)
  95   (imag :type real
  96         :ref-known (flushable movable)
  97         :ref-trans %imagpart
  98         :init :arg))
  99
 100 (define-primitive-object (array :lowtag other-pointer-lowtag
 101                                 :widetag t)
 102   ;; FILL-POINTER of an ARRAY is in the same place as LENGTH of a
 103   ;; VECTOR -- see SHRINK-VECTOR.
 104   (fill-pointer :type index
 105                 :ref-trans %array-fill-pointer
 106                 :ref-known (flushable foldable)
 107                 :set-trans (setf %array-fill-pointer)
 108                 :set-known (unsafe))
 109   (fill-pointer-p :type (member t nil)
 110                   :ref-trans %array-fill-pointer-p
 111                   :ref-known (flushable foldable)
 112                   :set-trans (setf %array-fill-pointer-p)
 113                   :set-known (unsafe))
 114   (elements :type index
 115             :ref-trans %array-available-elements
 116             :ref-known (flushable foldable)
 117             :set-trans (setf %array-available-elements)
 118             :set-known (unsafe))
 119   (data :type array
 120         :ref-trans %array-data-vector
 121         :ref-known (flushable foldable)
 122         :set-trans (setf %array-data-vector)
 123         :set-known (unsafe))
 124   (displacement :type (or index null)
 125                 :ref-trans %array-displacement
 126                 :ref-known (flushable foldable)
 127                 :set-trans (setf %array-displacement)
 128                 :set-known (unsafe))
 129   (displaced-p :type (member t nil)
 130                :ref-trans %array-displaced-p
 131                :ref-known (flushable foldable)
 132                :set-trans (setf %array-displaced-p)
 133                :set-known (unsafe))
 134   (dimensions :rest-p t))
 135
 136 (define-primitive-object (vector :type vector
 137                                  :lowtag other-pointer-lowtag
 138                                  :widetag t)
 139   ;; FILL-POINTER of an ARRAY is in the same place as LENGTH of a
 140   ;; VECTOR -- see SHRINK-VECTOR.
 141   (length :ref-trans sb!c::vector-length
 142           :type index)
 143   (data :rest-p t :c-type #!-alpha "unsigned long" #!+alpha "u32"))
 144
 145 (define-primitive-object (code :type code-component
 146                                :lowtag other-pointer-lowtag
 147                                :widetag t)
 148   (code-size :type index
 149              :ref-known (flushable movable)
 150              :ref-trans %code-code-size)
 151   (entry-points :type (or function null)
 152                 :ref-known (flushable)
 153                 :ref-trans %code-entry-points
 154                 :set-known (unsafe)
 155                 :set-trans (setf %code-entry-points))
 156   (debug-info :type t
 157               :ref-known (flushable)
 158               :ref-trans %code-debug-info
 159               :set-known (unsafe)
 160               :set-trans (setf %code-debug-info))
 161   (trace-table-offset)
 162   (constants :rest-p t))
 163
 164 (define-primitive-object (fdefn :type fdefn
 165                                 :lowtag other-pointer-lowtag
 166                                 :widetag fdefn-widetag)
 167   (name :ref-trans fdefn-name)
 168   (fun :type (or function null) :ref-trans fdefn-fun)
 169   (raw-addr :c-type #!-alpha "char *" #!+alpha "u32"))
 170
 171 ;;; a simple function (as opposed to hairier things like closures
 172 ;;; which are also subtypes of Common Lisp's FUNCTION type)
 173 (define-primitive-object (simple-fun :type function
 174                                      :lowtag fun-pointer-lowtag
 175                                      :widetag simple-fun-header-widetag)
 176   #!-(or x86 x86-64) (self :ref-trans %simple-fun-self
 177                :set-trans (setf %simple-fun-self))
 178   #!+(or x86 x86-64) (self
 179           ;; KLUDGE: There's no :SET-KNOWN, :SET-TRANS, :REF-KNOWN, or
 180           ;; :REF-TRANS here in this case. Instead, there's separate
 181           ;; DEFKNOWN/DEFINE-VOP/DEFTRANSFORM stuff in
 182           ;; compiler/x86/system.lisp to define and declare them by
 183           ;; hand. I don't know why this is, but that's (basically)
 184           ;; the way it was done in CMU CL, and it works. (It's not
 185           ;; exactly the same way it was done in CMU CL in that CMU
 186           ;; CL's allows duplicate DEFKNOWNs, blithely overwriting any
 187           ;; previous data associated with the previous DEFKNOWN, and
 188           ;; that property was used to mask the definitions here. In
 189           ;; SBCL as of 0.6.12.64 that's not allowed -- too confusing!
 190           ;; -- so we have to explicitly suppress the DEFKNOWNish
 191           ;; stuff here in order to allow this old hack to work in the
 192           ;; new world. -- WHN 2001-08-82
 193           )
 194   (next :type (or function null)
 195         :ref-known (flushable)
 196         :ref-trans %simple-fun-next
 197         :set-known (unsafe)
 198         :set-trans (setf %simple-fun-next))
 199   (name :ref-known (flushable)
 200         :ref-trans %simple-fun-name
 201         :set-known (unsafe)
 202         :set-trans (setf %simple-fun-name))
 203   (arglist :type list
 204            :ref-known (flushable)
 205            :ref-trans %simple-fun-arglist
 206            :set-known (unsafe)
 207            :set-trans (setf %simple-fun-arglist))
 208   (type :ref-known (flushable)
 209         :ref-trans %simple-fun-type
 210         :set-known (unsafe)
 211         :set-trans (setf %simple-fun-type))
 212   (xrefs :init :null
 213          :ref-trans %simple-fun-xrefs
 214          :ref-known (flushable)
 215          :set-trans (setf %simple-fun-xrefs)
 216          :set-known ())
 217   ;; the SB!C::DEBUG-FUN object corresponding to this object, or NIL for none
 218   #+nil ; FIXME: doesn't work (gotcha, lowly maintenoid!) See notes on bug 137.
 219   (debug-fun :ref-known (flushable)
 220              :ref-trans %simple-fun-debug-fun
 221              :set-known (unsafe)
 222              :set-trans (setf %simple-fun-debug-fun))
 223   (code :rest-p t :c-type "unsigned char"))
 224
 225 (define-primitive-object (return-pc :lowtag other-pointer-lowtag :widetag t)
 226   (return-point :c-type "unsigned char" :rest-p t))
 227
 228 (define-primitive-object (closure :lowtag fun-pointer-lowtag
 229                                   :widetag closure-header-widetag)
 230   (fun :init :arg :ref-trans %closure-fun)
 231   (info :rest-p t))
 232
 233 (define-primitive-object (funcallable-instance
 234                           :lowtag fun-pointer-lowtag
 235                           :widetag funcallable-instance-header-widetag
 236                           :alloc-trans %make-funcallable-instance)
 237   (trampoline :init :funcallable-instance-tramp)
 238   (function :ref-known (flushable) :ref-trans %funcallable-instance-function
 239             :set-known (unsafe) :set-trans (setf %funcallable-instance-function))
 240   (info :rest-p t))
 241
 242 (define-primitive-object (value-cell :lowtag other-pointer-lowtag
 243                                      :widetag value-cell-header-widetag
 244                                      ;; FIXME: We also have an explicit VOP
 245                                      ;; for this. Is this needed as well?
 246                                      :alloc-trans make-value-cell)
 247   (value :set-trans value-cell-set
 248          :set-known (unsafe)
 249          :ref-trans value-cell-ref
 250          :ref-known (flushable)
 251          :init :arg))
 252
 253 #!+alpha
 254 (define-primitive-object (sap :lowtag other-pointer-lowtag
 255                               :widetag sap-widetag)
 256   (padding)
 257   (pointer :c-type "char *" :length 2))
 258
 259 #!-alpha
 260 (define-primitive-object (sap :lowtag other-pointer-lowtag
 261                               :widetag sap-widetag)
 262   (pointer :c-type "char *"))
 263
 264
 265 (define-primitive-object (weak-pointer :type weak-pointer
 266                                        :lowtag other-pointer-lowtag
 267                                        :widetag weak-pointer-widetag
 268                                        :alloc-trans make-weak-pointer)
 269   (value :ref-trans sb!c::%weak-pointer-value :ref-known (flushable)
 270          :init :arg)
 271   (broken :type (member t nil)
 272           :ref-trans sb!c::%weak-pointer-broken :ref-known (flushable)
 273           :init :null)
 274   (next :c-type #!-alpha "struct weak_pointer *" #!+alpha "u32"))
 275
 276 ;;;; other non-heap data blocks
 277
 278 (define-primitive-object (binding)
 279   value
 280   symbol)
 281
 282 (define-primitive-object (unwind-block)
 283   (current-uwp :c-type #!-alpha "struct unwind_block *" #!+alpha "u32")
 284   (current-cont :c-type #!-alpha "lispobj *" #!+alpha "u32")
 285   #!-(or x86 x86-64) current-code
 286   entry-pc
 287   #!+win32 next-seh-frame
 288   #!+win32 seh-frame-handler)
 289
 290 (define-primitive-object (catch-block)
 291   (current-uwp :c-type #!-alpha "struct unwind_block *" #!+alpha "u32")
 292   (current-cont :c-type #!-alpha "lispobj *" #!+alpha "u32")
 293   #!-(or x86 x86-64) current-code
 294   entry-pc
 295   #!+win32 next-seh-frame
 296   #!+win32 seh-frame-handler
 297   tag
 298   (previous-catch :c-type #!-alpha "struct catch_block *" #!+alpha "u32")
 299   size)
 300
 301 ;;; (For an explanation of this, see the comments at the definition of
 302 ;;; KLUDGE-NONDETERMINISTIC-CATCH-BLOCK-SIZE.)
 303 (aver (= kludge-nondeterministic-catch-block-size catch-block-size))
 304 \f
 305 ;;;; symbols
 306
 307 (define-primitive-object (symbol :lowtag other-pointer-lowtag
 308                                  :widetag symbol-header-widetag
 309                                  :alloc-trans %make-symbol)
 310
 311   ;; Beware when changing this definition.  NIL-the-symbol is defined
 312   ;; using this layout, and NIL-the-end-of-list-marker is the cons
 313   ;; ( NIL . NIL ), living in the first two slots of NIL-the-symbol
 314   ;; (conses have no header).  Careful selection of lowtags ensures
 315   ;; that the same pointer can be used for both purposes:
 316   ;; OTHER-POINTER-LOWTAG is 7, LIST-POINTER-LOWTAG is 3, so if you
 317   ;; subtract 3 from (SB-KERNEL:GET-LISP-OBJ-ADDRESS 'NIL) you get the
 318   ;; first data slot, and if you subtract 7 you get a symbol header.
 319
 320   ;; also the CAR of NIL-as-end-of-list
 321   (value :init :unbound :ref-known (flushable) :ref-trans symbol-global-value)
 322   ;; also the CDR of NIL-as-end-of-list.  Its reffer needs special
 323   ;; care for this reason, as hash values must be fixnums.
 324   (hash :set-trans %set-symbol-hash)
 325
 326   (plist :ref-trans symbol-plist
 327          :set-trans %set-symbol-plist
 328          :cas-trans %compare-and-swap-symbol-plist
 329          :type list
 330          :init :null)
 331   (name :ref-trans symbol-name :init :arg)
 332   (package :ref-trans symbol-package
 333            :set-trans %set-symbol-package
 334            :init :null)
 335   #!+sb-thread (tls-index :ref-known (flushable) :ref-trans symbol-tls-index))
 336
 337 (define-primitive-object (complex-single-float
 338                           :lowtag other-pointer-lowtag
 339                           :widetag complex-single-float-widetag)
 340   (real :c-type "float")
 341   (imag :c-type "float"))
 342
 343 (define-primitive-object (complex-double-float
 344                           :lowtag other-pointer-lowtag
 345                           :widetag complex-double-float-widetag)
 346   #!-x86-64 (filler)
 347   (real :c-type "double" :length #!-x86-64 2 #!+x86-64 1)
 348   (imag :c-type "double" :length #!-x86-64 2 #!+x86-64 1))
 349
 350 #!+(and sb-lutex sb-thread)
 351 (define-primitive-object (lutex
 352                           :lowtag other-pointer-lowtag
 353                           :widetag lutex-widetag
 354                           :alloc-trans %make-lutex)
 355   (gen :c-type "long" :length 1)
 356   (live :c-type "long" :length 1)
 357   (next :c-type "struct lutex *" :length 1)
 358   (prev :c-type "struct lutex *" :length 1)
 359   (mutex :c-type "pthread_mutex_t *"
 360          :length 1)
 361   (mutexattr :c-type "pthread_mutexattr_t *"
 362              :length 1)
 363   (condition-variable :c-type "pthread_cond_t *"
 364                       :length 1))
 365
 366 ;;; this isn't actually a lisp object at all, it's a c structure that lives
 367 ;;; in c-land.  However, we need sight of so many parts of it from Lisp that
 368 ;;; it makes sense to define it here anyway, so that the GENESIS machinery
 369 ;;; can take care of maintaining Lisp and C versions.
 370 ;;; Hence the even-fixnum lowtag just so we don't get odd(sic) numbers
 371 ;;; added to the slot offsets
 372 (define-primitive-object (thread :lowtag even-fixnum-lowtag)
 373   ;; no_tls_value_marker is borrowed very briefly at thread startup to
 374   ;; pass the address of initial-function into new_thread_trampoline.
 375   ;; tls[0] = NO_TLS_VALUE_MARKER_WIDETAG because a the tls index slot
 376   ;; of a symbol is initialized to zero
 377   (no-tls-value-marker)
 378   (os-thread :c-type "volatile os_thread_t")
 379   ;; This is the original address at which the memory was allocated,
 380   ;; which may have different alignment then what we prefer to use.
 381   ;; Kept here so that when the thread dies we can releast the whole
 382   ;; memory we reserved.
 383   (os-address :c-type "void *" :length #!+alpha 2 #!-alpha 1)
 384   (binding-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 385   (binding-stack-pointer :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 386   (control-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 387   (control-stack-end :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 388   (alien-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 389   (alien-stack-pointer :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
 390   #!+gencgc (alloc-region :c-type "struct alloc_region" :length 5)
 391   (this :c-type "struct thread *" :length #!+alpha 2 #!-alpha 1)
 392   (prev :c-type "struct thread *" :length #!+alpha 2 #!-alpha 1)
 393   (next :c-type "struct thread *" :length #!+alpha 2 #!-alpha 1)
 394   ;; starting, running, suspended, dead
 395   (state :c-type "volatile lispobj")
 396   (tls-cookie)                          ;  on x86, the LDT index
 397   #!+(or x86 x86-64) (pseudo-atomic-bits)
 398   (interrupt-data :c-type "struct interrupt_data *"
 399                   :length #!+alpha 2 #!-alpha 1)
 400   (stepping)
 401   (interrupt-contexts :c-type "os_context_t *" :rest-p t))