src/vm.c

   1 /* Copyright (C) 2001 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 #include <string.h>
  43 #include "envs.h"
  44 #include "frames.h"
  45 #include "instructions.h"
  46 #include "objcodes.h"
  47 #include "programs.h"
  48 #include "vm.h"
  49
  50 /* I sometimes use this for debugging. */
  51 #define vm_puts(OBJ)                            \
  52 {                                               \
  53   scm_display (OBJ, scm_def_errp);              \
  54   scm_newline (scm_def_errp);                   \
  55 }
  56
  57 \f
  58 /*
  59  * VM Continuation
  60  */
  61
  62 scm_t_bits scm_tc16_vm_cont;
  63
  64
  65 #define SCM_VM_CONT_P(OBJ)      SCM_SMOB_PREDICATE (scm_tc16_vm_cont, OBJ)
  66 #define SCM_VM_CONT_VP(CONT)    ((struct scm_vm *) SCM_CELL_WORD_1 (CONT))
  67
  68 static SCM
  69 capture_vm_cont (struct scm_vm *vp)
  70 {
  71   struct scm_vm *p = scm_must_malloc (sizeof (*p), "capture_vm_cont");
  72   p->stack_size = vp->stack_limit - vp->sp;
  73   p->stack_base = scm_must_malloc (p->stack_size * sizeof (SCM),
  74                                    "capture_vm_cont");
  75   p->stack_limit = p->stack_base + p->stack_size - 2;
  76   p->ip = vp->ip;
  77   p->sp = (SCM *) (vp->stack_limit - vp->sp);
  78   p->fp = (SCM *) (vp->stack_limit - vp->fp);
  79   memcpy (p->stack_base, vp->sp + 1, vp->stack_size * sizeof (SCM));
  80   SCM_RETURN_NEWSMOB (scm_tc16_vm_cont, p);
  81 }
  82
  83 static void
  84 reinstate_vm_cont (struct scm_vm *vp, SCM cont)
  85 {
  86   struct scm_vm *p = SCM_VM_CONT_VP (cont);
  87   if (vp->stack_size < p->stack_size)
  88     {
  89       /* puts ("FIXME: Need to expand"); */
  90       abort ();
  91     }
  92   vp->ip = p->ip;
  93   vp->sp = vp->stack_limit - (int) p->sp;
  94   vp->fp = vp->stack_limit - (int) p->fp;
  95   memcpy (vp->sp + 1, p->stack_base, p->stack_size * sizeof (SCM));
  96 }
  97
  98 static SCM
  99 vm_cont_mark (SCM obj)
 100 {
 101   SCM *p;
 102   struct scm_vm *vp = SCM_VM_CONT_VP (obj);
 103   for (p = vp->stack_base; p <= vp->stack_limit; p++)
 104     if (SCM_NIMP (*p))
 105       scm_gc_mark (*p);
 106   return SCM_BOOL_F;
 107 }
 108
 109 static scm_sizet
 110 vm_cont_free (SCM obj)
 111 {
 112   struct scm_vm *p = SCM_VM_CONT_VP (obj);
 113   int size = sizeof (struct scm_vm) + p->stack_size * sizeof (SCM);
 114   scm_must_free (p->stack_base);
 115   scm_must_free (p);
 116   return size;
 117 }
 118
 119 \f
 120 /*
 121  * VM Internal functions
 122  */
 123
 124 SCM_SYMBOL (sym_vm_run, "vm-run");
 125 SCM_SYMBOL (sym_vm_error, "vm-error");
 126
 127 static scm_byte_t *
 128 vm_fetch_length (scm_byte_t *ip, size_t *lenp)
 129 {
 130   /* NOTE: format defined in system/vm/conv.scm */
 131   *lenp = *ip++;
 132   if (*lenp < 254)
 133     return ip;
 134   else if (*lenp == 254)
 135     {
 136       int b1 = *ip++;
 137       int b2 = *ip++;
 138       *lenp = (b1 << 8) + b2;
 139     }
 140   else
 141     {
 142       int b1 = *ip++;
 143       int b2 = *ip++;
 144       int b3 = *ip++;
 145       int b4 = *ip++;
 146       *lenp = (b1 << 24) + (b2 << 16) + (b3 << 8) + b4;
 147     }
 148   return ip;
 149 }
 150
 151 static SCM
 152 vm_heapify_frames_1 (struct scm_vm *vp, SCM *fp, SCM *sp, SCM **destp)
 153 {
 154   SCM frame;
 155   SCM *dl = SCM_FRAME_DYNAMIC_LINK (fp);
 156   SCM *src = SCM_FRAME_UPPER_ADDRESS (fp);
 157   SCM *dest = SCM_FRAME_LOWER_ADDRESS (fp);
 158
 159   if (!dl)
 160     {
 161       /* The top frame */
 162       frame = scm_c_make_heap_frame (fp);
 163       fp = SCM_HEAP_FRAME_POINTER (frame);
 164       SCM_FRAME_HEAP_LINK (fp) = SCM_BOOL_T;
 165     }
 166   else
 167     {
 168       /* Child frames */
 169       SCM link = SCM_FRAME_HEAP_LINK (dl);
 170       if (!SCM_FALSEP (link))
 171         link = SCM_FRAME_LOWER_ADDRESS (dl)[-1]; /* self link */
 172       else
 173         link = vm_heapify_frames_1 (vp, dl, dest - 1, &dest);
 174       frame = scm_c_make_heap_frame (fp);
 175       fp = SCM_HEAP_FRAME_POINTER (frame);
 176       SCM_FRAME_HEAP_LINK (fp)    = link;
 177       SCM_FRAME_DYNAMIC_LINK (fp) = SCM_HEAP_FRAME_POINTER (link);
 178     }
 179
 180   /* Move stack data */
 181   for (; src <= sp; src++, dest++)
 182     *dest = *src;
 183   *destp = dest;
 184
 185   return frame;
 186 }
 187
 188 static SCM
 189 vm_heapify_frames (SCM vm)
 190 {
 191   struct scm_vm *vp = SCM_VM_DATA (vm);
 192   if (SCM_FALSEP (SCM_FRAME_HEAP_LINK (vp->fp)))
 193     {
 194       SCM *dest;
 195       vp->this_frame = vm_heapify_frames_1 (vp, vp->fp, vp->sp, &dest);
 196       vp->fp = SCM_HEAP_FRAME_POINTER (vp->this_frame);
 197       vp->sp = dest - 1;
 198     }
 199   return vp->this_frame;
 200 }
 201
 202 \f
 203 /*
 204  * VM
 205  */
 206
 207 #define VM_DEFAULT_STACK_SIZE   (16 * 1024)
 208
 209 #define VM_REGULAR_ENGINE       0
 210 #define VM_DEBUG_ENGINE         1
 211
 212 #if 0
 213 #define VM_NAME   vm_regular_engine
 214 #define VM_ENGINE VM_REGULAR_ENGINE
 215 #include "vm_engine.c"
 216 #undef VM_NAME
 217 #undef VM_ENGINE
 218 #endif
 219
 220 #define VM_NAME   vm_debug_engine
 221 #define VM_ENGINE VM_DEBUG_ENGINE
 222 #include "vm_engine.c"
 223 #undef VM_NAME
 224 #undef VM_ENGINE
 225
 226 scm_t_bits scm_tc16_vm;
 227
 228 static SCM the_vm;
 229
 230 static SCM
 231 make_vm (void)
 232 #define FUNC_NAME "make_vm"
 233 {
 234   int i;
 235   struct scm_vm *vp = SCM_MUST_MALLOC (sizeof (struct scm_vm));
 236   vp->stack_size  = VM_DEFAULT_STACK_SIZE;
 237   vp->stack_base  = SCM_MUST_MALLOC (vp->stack_size * sizeof (SCM));
 238   vp->stack_limit = vp->stack_base + vp->stack_size - 3;
 239   vp->ip          = NULL;
 240   vp->sp          = vp->stack_base - 1;
 241   vp->fp          = NULL;
 242   vp->time        = 0;
 243   vp->clock       = 0;
 244   vp->options     = SCM_EOL;
 245   vp->this_frame  = SCM_BOOL_F;
 246   vp->last_frame  = SCM_BOOL_F;
 247   for (i = 0; i < SCM_VM_NUM_HOOKS; i++)
 248     vp->hooks[i] = SCM_BOOL_F;
 249   SCM_RETURN_NEWSMOB (scm_tc16_vm, vp);
 250 }
 251 #undef FUNC_NAME
 252
 253 static SCM
 254 vm_mark (SCM obj)
 255 {
 256   int i;
 257   struct scm_vm *vp = SCM_VM_DATA (obj);
 258
 259   /* mark the stack conservatively */
 260   scm_mark_locations ((SCM_STACKITEM *) vp->stack_base,
 261                       sizeof (SCM) * (vp->sp - vp->stack_base + 1));
 262
 263   /* mark other objects  */
 264   for (i = 0; i < SCM_VM_NUM_HOOKS; i++)
 265     scm_gc_mark (vp->hooks[i]);
 266   scm_gc_mark (vp->this_frame);
 267   scm_gc_mark (vp->last_frame);
 268   return vp->options;
 269 }
 270
 271 static scm_sizet
 272 vm_free (SCM obj)
 273 {
 274   struct scm_vm *vp = SCM_VM_DATA (obj);
 275   int size = (sizeof (struct scm_vm) + vp->stack_size * sizeof (SCM));
 276   scm_must_free (vp->stack_base);
 277   scm_must_free (vp);
 278   return size;
 279 }
 280
 281 SCM_SYMBOL (sym_debug, "debug");
 282
 283 SCM
 284 scm_vm_apply (SCM vm, SCM program, SCM args)
 285 #define FUNC_NAME "scm_vm_apply"
 286 {
 287   SCM_VALIDATE_PROGRAM (1, program);
 288   return vm_run (vm, program, args);
 289 }
 290 #undef FUNC_NAME
 291
 292 /* Scheme interface */
 293
 294 SCM_DEFINE (scm_vm_version, "vm-version", 0, 0, 0,
 295             (void),
 296             "")
 297 #define FUNC_NAME s_scm_vm_version
 298 {
 299   return scm_makfrom0str (VERSION);
 300 }
 301 #undef FUNC_NAME
 302
 303 SCM_DEFINE (scm_the_vm, "the-vm", 0, 0, 0,
 304             (),
 305             "")
 306 #define FUNC_NAME s_scm_the_vm
 307 {
 308   return the_vm;
 309 }
 310 #undef FUNC_NAME
 311
 312
 313 SCM_DEFINE (scm_vm_p, "vm?", 1, 0, 0,
 314             (SCM obj),
 315             "")
 316 #define FUNC_NAME s_scm_vm_p
 317 {
 318   return SCM_BOOL (SCM_VM_P (obj));
 319 }
 320 #undef FUNC_NAME
 321
 322 SCM_DEFINE (scm_make_vm, "make-vm", 0, 0, 0,
 323             (void),
 324             "")
 325 #define FUNC_NAME s_scm_make_vm,
 326 {
 327   return make_vm ();
 328 }
 329 #undef FUNC_NAME
 330
 331 SCM_DEFINE (scm_vm_ip, "vm:ip", 1, 0, 0,
 332             (SCM vm),
 333             "")
 334 #define FUNC_NAME s_scm_vm_ip
 335 {
 336   SCM_VALIDATE_VM (1, vm);
 337   return scm_ulong2num ((unsigned long) SCM_VM_DATA (vm)->ip);
 338 }
 339 #undef FUNC_NAME
 340
 341 SCM_DEFINE (scm_vm_sp, "vm:sp", 1, 0, 0,
 342             (SCM vm),
 343             "")
 344 #define FUNC_NAME s_scm_vm_sp
 345 {
 346   SCM_VALIDATE_VM (1, vm);
 347   return scm_ulong2num ((unsigned long) SCM_VM_DATA (vm)->sp);
 348 }
 349 #undef FUNC_NAME
 350
 351 SCM_DEFINE (scm_vm_fp, "vm:fp", 1, 0, 0,
 352             (SCM vm),
 353             "")
 354 #define FUNC_NAME s_scm_vm_fp
 355 {
 356   SCM_VALIDATE_VM (1, vm);
 357   return scm_ulong2num ((unsigned long) SCM_VM_DATA (vm)->fp);
 358 }
 359 #undef FUNC_NAME
 360
 361 #define VM_DEFINE_HOOK(n)                               \
 362 {                                                       \
 363   struct scm_vm *vp;                                    \
 364   SCM_VALIDATE_VM (1, vm);                              \
 365   vp = SCM_VM_DATA (vm);                                \
 366   if (SCM_FALSEP (vp->hooks[n]))                        \
 367     vp->hooks[n] = scm_make_hook (SCM_MAKINUM (1));     \
 368   return vp->hooks[n];                                  \
 369 }
 370
 371 SCM_DEFINE (scm_vm_boot_hook, "vm-boot-hook", 1, 0, 0,
 372             (SCM vm),
 373             "")
 374 #define FUNC_NAME s_scm_vm_boot_hook
 375 {
 376   VM_DEFINE_HOOK (SCM_VM_BOOT_HOOK);
 377 }
 378 #undef FUNC_NAME
 379
 380 SCM_DEFINE (scm_vm_halt_hook, "vm-halt-hook", 1, 0, 0,
 381             (SCM vm),
 382             "")
 383 #define FUNC_NAME s_scm_vm_halt_hook
 384 {
 385   VM_DEFINE_HOOK (SCM_VM_HALT_HOOK);
 386 }
 387 #undef FUNC_NAME
 388
 389 SCM_DEFINE (scm_vm_next_hook, "vm-next-hook", 1, 0, 0,
 390             (SCM vm),
 391             "")
 392 #define FUNC_NAME s_scm_vm_next_hook
 393 {
 394   VM_DEFINE_HOOK (SCM_VM_NEXT_HOOK);
 395 }
 396 #undef FUNC_NAME
 397
 398 SCM_DEFINE (scm_vm_break_hook, "vm-break-hook", 1, 0, 0,
 399             (SCM vm),
 400             "")
 401 #define FUNC_NAME s_scm_vm_break_hook
 402 {
 403   VM_DEFINE_HOOK (SCM_VM_BREAK_HOOK);
 404 }
 405 #undef FUNC_NAME
 406
 407 SCM_DEFINE (scm_vm_enter_hook, "vm-enter-hook", 1, 0, 0,
 408             (SCM vm),
 409             "")
 410 #define FUNC_NAME s_scm_vm_enter_hook
 411 {
 412   VM_DEFINE_HOOK (SCM_VM_ENTER_HOOK);
 413 }
 414 #undef FUNC_NAME
 415
 416 SCM_DEFINE (scm_vm_apply_hook, "vm-apply-hook", 1, 0, 0,
 417             (SCM vm),
 418             "")
 419 #define FUNC_NAME s_scm_vm_apply_hook
 420 {
 421   VM_DEFINE_HOOK (SCM_VM_APPLY_HOOK);
 422 }
 423 #undef FUNC_NAME
 424
 425 SCM_DEFINE (scm_vm_exit_hook, "vm-exit-hook", 1, 0, 0,
 426             (SCM vm),
 427             "")
 428 #define FUNC_NAME s_scm_vm_exit_hook
 429 {
 430   VM_DEFINE_HOOK (SCM_VM_EXIT_HOOK);
 431 }
 432 #undef FUNC_NAME
 433
 434 SCM_DEFINE (scm_vm_return_hook, "vm-return-hook", 1, 0, 0,
 435             (SCM vm),
 436             "")
 437 #define FUNC_NAME s_scm_vm_return_hook
 438 {
 439   VM_DEFINE_HOOK (SCM_VM_RETURN_HOOK);
 440 }
 441 #undef FUNC_NAME
 442
 443 SCM_DEFINE (scm_vm_option, "vm-option", 2, 0, 0,
 444             (SCM vm, SCM key),
 445             "")
 446 #define FUNC_NAME s_scm_vm_option
 447 {
 448   SCM_VALIDATE_VM (1, vm);
 449   return scm_assq_ref (SCM_VM_DATA (vm)->options, key);
 450 }
 451 #undef FUNC_NAME
 452
 453 SCM_DEFINE (scm_set_vm_option_x, "set-vm-option!", 3, 0, 0,
 454             (SCM vm, SCM key, SCM val),
 455             "")
 456 #define FUNC_NAME s_scm_set_vm_option_x
 457 {
 458   SCM_VALIDATE_VM (1, vm);
 459   SCM_VM_DATA (vm)->options
 460     = scm_assq_set_x (SCM_VM_DATA (vm)->options, key, val);
 461   return SCM_UNSPECIFIED;
 462 }
 463 #undef FUNC_NAME
 464
 465 SCM_DEFINE (scm_vm_stats, "vm-stats", 1, 0, 0,
 466             (SCM vm),
 467             "")
 468 #define FUNC_NAME s_scm_vm_stats
 469 {
 470   SCM stats;
 471
 472   SCM_VALIDATE_VM (1, vm);
 473
 474   stats = scm_make_vector (scm_from_int (2), SCM_UNSPECIFIED);
 475   scm_vector_set_x (stats, scm_from_int (0),
 476                     scm_from_ulong (SCM_VM_DATA (vm)->time));
 477   scm_vector_set_x (stats, scm_from_int (1),
 478                     scm_from_ulong (SCM_VM_DATA (vm)->clock));
 479
 480   return stats;
 481 }
 482 #undef FUNC_NAME
 483
 484 #define VM_CHECK_RUNNING(vm)                            \
 485   if (!SCM_VM_DATA (vm)->ip)                            \
 486     SCM_MISC_ERROR ("Not running", SCM_LIST1 (vm))
 487
 488 SCM_DEFINE (scm_vm_this_frame, "vm-this-frame", 1, 0, 0,
 489             (SCM vm),
 490             "")
 491 #define FUNC_NAME s_scm_vm_this_frame
 492 {
 493   SCM_VALIDATE_VM (1, vm);
 494   return SCM_VM_DATA (vm)->this_frame;
 495 }
 496 #undef FUNC_NAME
 497
 498 SCM_DEFINE (scm_vm_last_frame, "vm-last-frame", 1, 0, 0,
 499             (SCM vm),
 500             "")
 501 #define FUNC_NAME s_scm_vm_last_frame
 502 {
 503   SCM_VALIDATE_VM (1, vm);
 504   return SCM_VM_DATA (vm)->last_frame;
 505 }
 506 #undef FUNC_NAME
 507
 508 SCM_DEFINE (scm_vm_fetch_code, "vm-fetch-code", 1, 0, 0,
 509             (SCM vm),
 510             "")
 511 #define FUNC_NAME s_scm_vm_fetch_code
 512 {
 513   int i;
 514   SCM list;
 515   scm_byte_t *ip;
 516   struct scm_instruction *p;
 517
 518   SCM_VALIDATE_VM (1, vm);
 519   VM_CHECK_RUNNING (vm);
 520
 521   ip = SCM_VM_DATA (vm)->ip;
 522   p = SCM_INSTRUCTION (*ip);
 523
 524   list = SCM_LIST1 (scm_str2symbol (p->name));
 525   for (i = 1; i <= p->len; i++)
 526     list = scm_cons (SCM_MAKINUM (ip[i]), list);
 527   return scm_reverse_x (list, SCM_EOL);
 528 }
 529 #undef FUNC_NAME
 530
 531 SCM_DEFINE (scm_vm_fetch_stack, "vm-fetch-stack", 1, 0, 0,
 532             (SCM vm),
 533             "")
 534 #define FUNC_NAME s_scm_vm_fetch_stack
 535 {
 536   SCM *sp;
 537   SCM ls = SCM_EOL;
 538   struct scm_vm *vp;
 539
 540   SCM_VALIDATE_VM (1, vm);
 541   VM_CHECK_RUNNING (vm);
 542
 543   vp = SCM_VM_DATA (vm);
 544   for (sp = vp->stack_base; sp <= vp->sp; sp++)
 545     ls = scm_cons (*sp, ls);
 546   return ls;
 547 }
 548 #undef FUNC_NAME
 549
 550 \f
 551 /*
 552  * Initialize
 553  */
 554
 555 void
 556 scm_init_vm (void)
 557 {
 558   scm_init_frames ();
 559   scm_init_instructions ();
 560   scm_init_objcodes ();
 561   scm_init_programs ();
 562
 563   scm_tc16_vm_cont = scm_make_smob_type ("vm-cont", 0);
 564   scm_set_smob_mark (scm_tc16_vm_cont, vm_cont_mark);
 565   scm_set_smob_free (scm_tc16_vm_cont, vm_cont_free);
 566
 567   scm_tc16_vm = scm_make_smob_type ("vm", 0);
 568   scm_set_smob_mark (scm_tc16_vm, vm_mark);
 569   scm_set_smob_free (scm_tc16_vm, vm_free);
 570   scm_set_smob_apply (scm_tc16_vm, scm_vm_apply, 1, 0, 1);
 571
 572   the_vm = scm_permanent_object (make_vm ());
 573
 574 #ifndef SCM_MAGIC_SNARFER
 575 #include "vm.x"
 576 #endif
 577 }
 578
 579 /*
 580   Local Variables:
 581   c-file-style: "gnu"
 582   End:
 583 */