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;;;; * The GC scavenging code (and for all I know other GC code too) 18;;;; is not automatically generated from these layouts, but instead 19;;;; was hand-written to correspond to them. The offsets are 20;;;; automatically propagated into the GC scavenging code, but the 21;;;; existence of slots, and whether they should be scavenged, is 22;;;; not automatically propagated. Thus e.g. if you add a 23;;;; SIMPLE-FUN-DEBUG-INFO slot holding a tagged object which needs 24;;;; to be GCed, you need to tweak scav_code_header() and 25;;;; verify_space() in gencgc.c, and the corresponding code in gc.c. 26;;;; * The src/runtime/print.c code (used by LDB) is implemented 27;;;; using hand-written lists of slot names, which aren't automatically 28;;;; generated from the code in this file. 29;;;; * Various code (e.g. STATIC-FSET in genesis.lisp) is hard-wired 30;;;; to know the name of the last slot of the object the code works 31;;;; with, and implicitly to know that the last slot is special (being 32;;;; the beginning of an arbitrary-length sequence of bytes following 33;;;; the fixed-layout slots). 34;;;; -- WHN 2001-12-29 35 36;;;; the primitive objects themselves 37 38(!define-primitive-object (cons :type cons 39 :lowtag list-pointer-lowtag 40 :alloc-trans cons) 41 (car :ref-trans car :set-trans sb!c::%rplaca :init :arg 42 :cas-trans %compare-and-swap-car) 43 (cdr :ref-trans cdr :set-trans sb!c::%rplacd :init :arg 44 :cas-trans %compare-and-swap-cdr)) 45 46(!define-primitive-object (instance :lowtag instance-pointer-lowtag 47 :widetag instance-header-widetag 48 :alloc-trans %make-instance) 49 (slots :rest-p t)) 50 51(!define-primitive-object (bignum :lowtag other-pointer-lowtag 52 :widetag bignum-widetag 53 :alloc-trans sb!bignum::%allocate-bignum) 54 (digits :rest-p t :c-type #!-alpha "sword_t" #!+alpha "u32")) 55 56(!define-primitive-object (ratio :type ratio 57 :lowtag other-pointer-lowtag 58 :widetag ratio-widetag 59 :alloc-trans %make-ratio) 60 (numerator :type integer 61 :ref-known (flushable movable) 62 :ref-trans %numerator 63 :init :arg) 64 (denominator :type integer 65 :ref-known (flushable movable) 66 :ref-trans %denominator 67 :init :arg)) 68 69#!-64-bit 70(!define-primitive-object (single-float :lowtag other-pointer-lowtag 71 :widetag single-float-widetag) 72 (value :c-type "float")) 73 74(!define-primitive-object (double-float :lowtag other-pointer-lowtag 75 :widetag double-float-widetag) 76 #!-64-bit (filler) 77 (value :c-type "double" :length #.(/ 64 n-word-bits))) 78 79#!+long-float 80(!define-primitive-object (long-float :lowtag other-pointer-lowtag 81 :widetag long-float-widetag) 82 #!+sparc (filler) 83 (value :c-type "long double" :length #!+x86 3 #!+sparc 4)) 84 85(!define-primitive-object (complex :type complex 86 :lowtag other-pointer-lowtag 87 :widetag complex-widetag 88 :alloc-trans %make-complex) 89 (real :type real 90 :ref-known (flushable movable) 91 :ref-trans %realpart 92 :init :arg) 93 (imag :type real 94 :ref-known (flushable movable) 95 :ref-trans %imagpart 96 :init :arg)) 97 98(!define-primitive-object (array :lowtag other-pointer-lowtag 99 :widetag t) 100 ;; FILL-POINTER of an ARRAY is in the same place as LENGTH of a 101 ;; VECTOR -- see SHRINK-VECTOR. 102 (fill-pointer :type index 103 :ref-trans %array-fill-pointer 104 :ref-known (flushable foldable) 105 :set-trans (setf %array-fill-pointer) 106 :set-known ()) 107 (fill-pointer-p :type (member t nil) 108 :ref-trans %array-fill-pointer-p 109 :ref-known (flushable foldable) 110 :set-trans (setf %array-fill-pointer-p) 111 :set-known ()) 112 (elements :type index 113 :ref-trans %array-available-elements 114 :ref-known (flushable foldable) 115 :set-trans (setf %array-available-elements) 116 :set-known ()) 117 (data :type array 118 ;; FIXME: terrible name for the accessor. 119 ;; It is in general just an ARRAY, 120 ;; and should be named %ARRAY-DATA. 121 :ref-trans %array-data-vector 122 :ref-known (flushable foldable) 123 :set-trans (setf %array-data-vector) 124 :set-known ()) 125 (displacement :type (or index null) 126 :ref-trans %array-displacement 127 :ref-known (flushable foldable) 128 :set-trans (setf %array-displacement) 129 :set-known ()) 130 (displaced-p :type t 131 :ref-trans %array-displaced-p 132 :ref-known (flushable foldable) 133 :set-trans (setf %array-displaced-p) 134 :set-known ()) 135 (displaced-from :type list 136 :ref-trans %array-displaced-from 137 :ref-known (flushable) 138 :set-trans (setf %array-displaced-from) 139 :set-known ()) 140 (dimensions :rest-p t)) 141 142(!define-primitive-object (vector :type vector 143 :lowtag other-pointer-lowtag 144 :widetag t) 145 ;; FILL-POINTER of an ARRAY is in the same place as LENGTH of a 146 ;; VECTOR -- see SHRINK-VECTOR. 147 (length :ref-trans sb!c::vector-length 148 :type index) 149 (data :rest-p t :c-type #!-alpha "uword_t" #!+alpha "u32")) 150 151;;; The header contains the size of slots and constants in words. 152(!define-primitive-object (code :type code-component 153 :lowtag other-pointer-lowtag 154 :widetag t) 155 ;; This is the size of instructions in bytes, not aligned. 156 ;; Adding the size from the header and aligned code-size will yield 157 ;; the total size of the code-object. 158 (code-size :type index 159 :ref-known (flushable movable) 160 :ref-trans %code-code-size) 161 (debug-info :type t 162 :ref-known (flushable) 163 :ref-trans %code-debug-info 164 :set-known () 165 :set-trans (setf %code-debug-info)) 166 #!-64-bit 167 (n-entries :type fixnum 168 :set-known () 169 :set-trans (setf %code-n-entries) 170 :ref-trans %code-n-entries 171 :ref-known (flushable foldable)) 172 (constants :rest-p t)) 173 174(!define-primitive-object (fdefn :type fdefn 175 :lowtag other-pointer-lowtag 176 :widetag fdefn-widetag) 177 (name :ref-trans fdefn-name 178 :set-trans %set-fdefn-name :set-known ()) 179 (fun :type (or function null) :ref-trans fdefn-fun) 180 (raw-addr :c-type #!-alpha "char *" #!+alpha "u32")) 181 182;;; a simple function (as opposed to hairier things like closures 183;;; which are also subtypes of Common Lisp's FUNCTION type) 184(!define-primitive-object (simple-fun :type function 185 :lowtag fun-pointer-lowtag 186 :widetag simple-fun-header-widetag) 187 #!-(or x86 x86-64) (self :ref-trans %simple-fun-self 188 :set-trans (setf %simple-fun-self)) 189 ;; FIXME: we don't currently detect/prevent at compile-time the bad 190 ;; scenario this comment claims to disallow, as determined by re-enabling 191 ;; these SET- and REF- specifiers, which led to a cold-init crash. 192 #!+(or x86 x86-64) (self 193 ;; KLUDGE: There's no :SET-KNOWN, :SET-TRANS, :REF-KNOWN, or 194 ;; :REF-TRANS here in this case. Instead, there's separate 195 ;; DEFKNOWN/DEFINE-VOP/DEFTRANSFORM stuff in 196 ;; compiler/x86/system.lisp to define and declare them by 197 ;; hand. I don't know why this is, but that's (basically) 198 ;; the way it was done in CMU CL, and it works. (It's not 199 ;; exactly the same way it was done in CMU CL in that CMU 200 ;; CL's allows duplicate DEFKNOWNs, blithely overwriting any 201 ;; previous data associated with the previous DEFKNOWN, and 202 ;; that property was used to mask the definitions here. In 203 ;; SBCL as of 0.6.12.64 that's not allowed -- too confusing! 204 ;; -- so we have to explicitly suppress the DEFKNOWNish 205 ;; stuff here in order to allow this old hack to work in the 206 ;; new world. -- WHN 2001-08-82 207 ) 208 (name :ref-known (flushable) 209 :ref-trans %simple-fun-name 210 :set-known () 211 :set-trans (setf %simple-fun-name)) 212 (arglist :type list 213 :ref-known (flushable) 214 :ref-trans %simple-fun-arglist 215 :set-known () 216 :set-trans (setf %simple-fun-arglist)) 217 (type :ref-known (flushable) 218 ;; %%SIMPLE-FUN-TYPE is used only by %SIMPLE-FUN-TYPE. 219 ;; Nobody should care that %SIMPLE-FUN-TYPE isn't open-coded. 220 :ref-trans %%simple-fun-type 221 :set-known () 222 :set-trans (setf %simple-fun-type)) 223 ;; NIL for empty, STRING for a docstring, SIMPLE-VECTOR for XREFS, and (CONS 224 ;; STRING SIMPLE-VECTOR) for both. 225 (info :init :null 226 :ref-trans %simple-fun-info 227 :ref-known (flushable) 228 :set-trans (setf %simple-fun-info) 229 :set-known ()) 230 ;; the SB!C::DEBUG-FUN object corresponding to this object, or NIL for none 231 #+nil ; FIXME: doesn't work (gotcha, lowly maintenoid!) See notes on bug 137. 232 (debug-fun :ref-known (flushable) 233 :ref-trans %simple-fun-debug-fun 234 :set-known () 235 :set-trans (setf %simple-fun-debug-fun)) 236 (code :rest-p t :c-type "unsigned char")) 237 238(!define-primitive-object (return-pc :lowtag other-pointer-lowtag :widetag t) 239 (return-point :c-type "unsigned char" :rest-p t)) 240 241(!define-primitive-object (closure :lowtag fun-pointer-lowtag 242 :widetag closure-header-widetag) 243 ;; %CLOSURE-FUN should never be invoked on x86[-64]. 244 ;; The above remark at %SIMPLE-FUN-SELF is relevant in its sentiment, 245 ;; but actually no longer true - the confusing situation is not caught 246 ;; until too late. But at least this one was nonfatal. 247 #!-(or x86 x86-64) (fun :init :arg :ref-trans %closure-fun) 248 #!+(or x86 x86-64) (fun :init :arg) 249 (info :rest-p t)) 250 251(!define-primitive-object (funcallable-instance 252 :lowtag fun-pointer-lowtag 253 :widetag funcallable-instance-header-widetag 254 :alloc-trans %make-funcallable-instance) 255 (trampoline :init :funcallable-instance-tramp) 256 ;; TODO: if we can switch places of 'function' and 'fsc-instance-slots' 257 ;; (at least for the builds with compact-instance-header) 258 ;; then for both funcallable and non-funcallable instances, 259 ;; the CLOS slot vector will be in the word 5 bytes past the tagged pointer. 260 ;; This shouldn't be too hard to arrange, since nothing needs to know where 261 ;; the tagged function lives except the funcallable instance trampoline. 262 (function :ref-known (flushable) :ref-trans %funcallable-instance-function 263 :set-known () :set-trans (setf %funcallable-instance-function)) 264 (info :rest-p t)) 265 266(!define-primitive-object (value-cell :lowtag other-pointer-lowtag 267 :widetag value-cell-header-widetag 268 ;; FIXME: We also have an explicit VOP 269 ;; for this. Is this needed as well? 270 :alloc-trans make-value-cell) 271 (value :set-trans value-cell-set 272 :set-known () 273 :ref-trans value-cell-ref 274 :ref-known (flushable) 275 :init :arg)) 276 277(!define-primitive-object (sap :lowtag other-pointer-lowtag 278 :widetag sap-widetag) 279 (pointer :c-type "char *" :pointer t)) 280 281 282(!define-primitive-object (weak-pointer :type weak-pointer 283 :lowtag other-pointer-lowtag 284 :widetag weak-pointer-widetag 285 :alloc-trans make-weak-pointer) 286 ;; FIXME: SB!C should be almost *anything* but that. Probably SB!KERNEL 287 (value :ref-trans sb!c::%weak-pointer-value :ref-known (flushable) 288 :init :arg) 289 (broken :type (member t nil) 290 :ref-trans sb!c::%weak-pointer-broken :ref-known (flushable) 291 :init :null) 292 (next :c-type #!-alpha "struct weak_pointer *" #!+alpha "u32")) 293 294;;;; other non-heap data blocks 295 296(!define-primitive-object (binding) 297 value 298 symbol) ;; on sb-thread, this is actually a tls-index 299 300(!define-primitive-object (unwind-block) 301 (uwp :c-type #!-alpha "struct unwind_block *" #!+alpha "u32") 302 (cfp :c-type #!-alpha "lispobj *" #!+alpha "u32") 303 #!-(or x86 x86-64) code 304 entry-pc 305 #!+win32 next-seh-frame 306 #!+win32 seh-frame-handler) 307 308(!define-primitive-object (catch-block) 309 (uwp :c-type #!-alpha "struct unwind_block *" #!+alpha "u32") 310 (cfp :c-type #!-alpha "lispobj *" #!+alpha "u32") 311 #!-(or x86 x86-64) code 312 entry-pc 313 #!+(and win32 x86) next-seh-frame 314 #!+(and win32 x86) seh-frame-handler 315 tag 316 (previous-catch :c-type #!-alpha "struct catch_block *" #!+alpha "u32")) 317 318;;;; symbols 319 320(!define-primitive-object (symbol :lowtag other-pointer-lowtag 321 :widetag symbol-header-widetag 322 :alloc-trans %%make-symbol 323 :type symbol) 324 325 ;; Beware when changing this definition. NIL-the-symbol is defined 326 ;; using this layout, and NIL-the-end-of-list-marker is the cons 327 ;; ( NIL . NIL ), living in the first two slots of NIL-the-symbol 328 ;; (conses have no header). Careful selection of lowtags ensures 329 ;; that the same pointer can be used for both purposes: 330 ;; OTHER-POINTER-LOWTAG is 7, LIST-POINTER-LOWTAG is 3, so if you 331 ;; subtract 3 from (SB-KERNEL:GET-LISP-OBJ-ADDRESS 'NIL) you get the 332 ;; first data slot, and if you subtract 7 you get a symbol header. 333 334 ;; also the CAR of NIL-as-end-of-list 335 (value :init :unbound 336 :set-trans %set-symbol-global-value 337 :set-known ()) 338 ;; also the CDR of NIL-as-end-of-list. Its reffer needs special 339 ;; care for this reason, as hash values must be fixnums. 340 (hash :set-trans %set-symbol-hash) 341 342 (info :ref-trans symbol-info :ref-known (flushable) 343 :set-trans (setf symbol-info) 344 :set-known () 345 :cas-trans %compare-and-swap-symbol-info 346 :type (or simple-vector list) 347 :init :null) 348 (name :ref-trans symbol-name :init :arg) 349 (package :ref-trans symbol-package 350 :set-trans %set-symbol-package 351 :init :null) 352 ;; 0 tls-index means no tls-index is allocated 353 ;; 64-bit put the tls-index in the header word. 354 #!+(and sb-thread (not 64-bit)) 355 (tls-index :ref-known (flushable) :ref-trans symbol-tls-index)) 356 357(!define-primitive-object (complex-single-float 358 :lowtag other-pointer-lowtag 359 :widetag complex-single-float-widetag) 360 #!+64-bit 361 (data :c-type "struct { float data[2]; } ") 362 #!-64-bit 363 (real :c-type "float") 364 #!-64-bit 365 (imag :c-type "float")) 366 367(!define-primitive-object (complex-double-float 368 :lowtag other-pointer-lowtag 369 :widetag complex-double-float-widetag) 370 (filler) 371 (real :c-type "double" :length #.(/ 64 n-word-bits)) 372 (imag :c-type "double" :length #.(/ 64 n-word-bits))) 373 374#!+sb-simd-pack 375(!define-primitive-object (simd-pack 376 :lowtag other-pointer-lowtag 377 :widetag simd-pack-widetag) 378 (tag :ref-trans %simd-pack-tag 379 :attributes (movable flushable) 380 :type fixnum) 381 (lo-value :c-type "long" :type (unsigned-byte 64)) 382 (hi-value :c-type "long" :type (unsigned-byte 64))) 383 384;;; this isn't actually a lisp object at all, it's a c structure that lives 385;;; in c-land. However, we need sight of so many parts of it from Lisp that 386;;; it makes sense to define it here anyway, so that the GENESIS machinery 387;;; can take care of maintaining Lisp and C versions. 388(!define-primitive-object (thread) 389 ;; no_tls_value_marker is borrowed very briefly at thread startup to 390 ;; pass the address of initial-function into new_thread_trampoline. 391 ;; tls[0] = NO_TLS_VALUE_MARKER_WIDETAG because a the tls index slot 392 ;; of a symbol is initialized to zero 393 (no-tls-value-marker) 394 (os-thread :c-type "os_thread_t") 395 ;; This is the original address at which the memory was allocated, 396 ;; which may have different alignment then what we prefer to use. 397 ;; Kept here so that when the thread dies we can release the whole 398 ;; memory we reserved. 399 (os-address :c-type "void *" :pointer t) 400 401 ;; Keep these next six slots (alloc-region being figured in as 1 slot) 402 ;; near the beginning of the structure so that x86[-64] assembly code 403 ;; can use single-byte displacements from thread-base-tn. 404 ;; Doing so reduces code size for allocation sequences and special variable 405 ;; manipulations by fixing their TLS offsets to be < 2^7, the largest 406 ;; aligned displacement fitting in a signed byte. 407 #!+gencgc (alloc-region :c-type "struct alloc_region" :length 5) 408 #!+sb-thread (pseudo-atomic-bits #!+(or x86 x86-64) :special #!+(or x86 x86-64) *pseudo-atomic-bits*) 409 ;; next two not used in C, but this wires the TLS offsets to small values 410 #!+(and x86-64 sb-thread) 411 (current-catch-block :special *current-catch-block*) 412 #!+(and x86-64 sb-thread) 413 (current-unwind-protect-block :special *current-unwind-protect-block*) 414 (alien-stack-pointer :c-type "lispobj *" :pointer t 415 :special *alien-stack-pointer*) 416 (binding-stack-pointer :c-type "lispobj *" :pointer t 417 :special *binding-stack-pointer*) 418 (stepping) 419 ;; END of slots to keep near the beginning. 420 421 ;; These aren't accessed (much) from Lisp, so don't really care 422 ;; if it takes a 4-byte displacement. 423 (alien-stack-start :c-type "lispobj *" :pointer t) 424 (binding-stack-start :c-type "lispobj *" :pointer t 425 :special *binding-stack-start*) 426 427 #!+sb-thread 428 (os-attr :c-type "pthread_attr_t *" :pointer t) 429 #!+(and sb-thread (not sb-safepoint)) 430 (state-sem :c-type "os_sem_t *" :pointer t) 431 #!+(and sb-thread (not sb-safepoint)) 432 (state-not-running-sem :c-type "os_sem_t *" :pointer t) 433 #!+(and sb-thread (not sb-safepoint)) 434 (state-not-running-waitcount :c-type "int" :length 1) 435 #!+(and sb-thread (not sb-safepoint)) 436 (state-not-stopped-sem :c-type "os_sem_t *" :pointer t) 437 #!+(and sb-thread (not sb-safepoint)) 438 (state-not-stopped-waitcount :c-type "int" :length 1) 439 (control-stack-start :c-type "lispobj *" :pointer t 440 :special *control-stack-start*) 441 (control-stack-end :c-type "lispobj *" :pointer t 442 :special *control-stack-end*) 443 (control-stack-guard-page-protected) 444 #!+win32 (private-events :c-type "struct private_events" :length 2) 445 (this :c-type "struct thread *" :pointer t) 446 (prev :c-type "struct thread *" :pointer t) 447 (next :c-type "struct thread *" :pointer t) 448 ;; starting, running, suspended, dead 449 (state :c-type "lispobj") 450 451 #!+x86 (tls-cookie) ; LDT index 452 (interrupt-data :c-type "struct interrupt_data *" 453 :pointer t) 454 ;; For various reasons related to pseudo-atomic and interrupt 455 ;; handling, we need to know if the machine context is in Lisp code 456 ;; or not. On non-threaded targets, this is a global variable in 457 ;; the runtime, but it's clearly a per-thread value. 458 #!+sb-thread 459 (foreign-function-call-active :c-type "boolean") 460 ;; Same as above for the location of the current control stack frame. 461 #!+(and sb-thread (not (or x86 x86-64))) 462 (control-frame-pointer :c-type "lispobj *") 463 ;; Same as above for the location of the current control stack 464 ;; pointer. This is also used on threaded x86oids to allow LDB to 465 ;; print an approximation of the CSP as needed. 466 #!+sb-thread 467 (control-stack-pointer :c-type "lispobj *") 468 #!+mach-exception-handler 469 (mach-port-name :c-type "mach_port_name_t") 470 ;; Context base pointer for running on top of system libraries built using 471 ;; -fomit-frame-pointer. Currently truly required and implemented only 472 ;; for (and win32 x86-64), but could be generalized to other platforms if 473 ;; needed: 474 #!+win32 (carried-base-pointer :c-type "os_context_register_t") 475 #!+sb-safepoint (csp-around-foreign-call :c-type "lispobj *") 476 #!+sb-safepoint (pc-around-foreign-call :c-type "lispobj *") 477 #!+win32 (synchronous-io-handle-and-flag :c-type "HANDLE" :length 1) 478 #!+(and sb-safepoint-strictly (not win32)) 479 (sprof-alloc-region :c-type "struct alloc_region" :length 5) 480 (interrupt-contexts :c-type "os_context_t *" :rest-p t :pointer t)) 481