libguile/vm-i-system.c

   1 /* Copyright (C) 2001,2008,2009 Free Software Foundation, Inc.
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public License
   5  * as published by the Free Software Foundation; either version 3 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301 USA
  17  */
  18
  19
  20 /* This file is included in vm_engine.c */
  21
  22 \f
  23 /*
  24  * Basic operations
  25  */
  26
  27 VM_DEFINE_INSTRUCTION (0, nop, "nop", 0, 0, 0)
  28 {
  29   NEXT;
  30 }
  31
  32 VM_DEFINE_INSTRUCTION (1, halt, "halt", 0, 0, 0)
  33 {
  34   vp->time += scm_c_get_internal_run_time () - start_time;
  35   HALT_HOOK ();
  36   nvalues = SCM_I_INUM (*sp--);
  37   NULLSTACK (1);
  38   if (nvalues == 1)
  39     POP (finish_args);
  40   else
  41     {
  42       POP_LIST (nvalues);
  43       POP (finish_args);
  44       SYNC_REGISTER ();
  45       finish_args = scm_values (finish_args);
  46     }
  47
  48   {
  49 #ifdef VM_ENABLE_STACK_NULLING
  50     SCM *old_sp = sp;
  51 #endif
  52
  53     /* Restore registers */
  54     sp = SCM_FRAME_LOWER_ADDRESS (fp) - 1;
  55     /* Setting the ip here doesn't actually affect control flow, as the calling
  56        code will restore its own registers, but it does help when walking the
  57        stack */
  58     ip = SCM_FRAME_RETURN_ADDRESS (fp);
  59     fp = SCM_FRAME_DYNAMIC_LINK (fp);
  60     NULLSTACK (old_sp - sp);
  61   }
  62
  63   goto vm_done;
  64 }
  65
  66 VM_DEFINE_INSTRUCTION (2, break, "break", 0, 0, 0)
  67 {
  68   BREAK_HOOK ();
  69   NEXT;
  70 }
  71
  72 VM_DEFINE_INSTRUCTION (3, drop, "drop", 0, 1, 0)
  73 {
  74   DROP ();
  75   NEXT;
  76 }
  77
  78 VM_DEFINE_INSTRUCTION (4, dup, "dup", 0, 0, 1)
  79 {
  80   SCM x = *sp;
  81   PUSH (x);
  82   NEXT;
  83 }
  84
  85 \f
  86 /*
  87  * Object creation
  88  */
  89
  90 VM_DEFINE_INSTRUCTION (5, void, "void", 0, 0, 1)
  91 {
  92   PUSH (SCM_UNSPECIFIED);
  93   NEXT;
  94 }
  95
  96 VM_DEFINE_INSTRUCTION (6, make_true, "make-true", 0, 0, 1)
  97 {
  98   PUSH (SCM_BOOL_T);
  99   NEXT;
 100 }
 101
 102 VM_DEFINE_INSTRUCTION (7, make_false, "make-false", 0, 0, 1)
 103 {
 104   PUSH (SCM_BOOL_F);
 105   NEXT;
 106 }
 107
 108 VM_DEFINE_INSTRUCTION (8, make_eol, "make-eol", 0, 0, 1)
 109 {
 110   PUSH (SCM_EOL);
 111   NEXT;
 112 }
 113
 114 VM_DEFINE_INSTRUCTION (9, make_int8, "make-int8", 1, 0, 1)
 115 {
 116   PUSH (SCM_I_MAKINUM ((signed char) FETCH ()));
 117   NEXT;
 118 }
 119
 120 VM_DEFINE_INSTRUCTION (10, make_int8_0, "make-int8:0", 0, 0, 1)
 121 {
 122   PUSH (SCM_INUM0);
 123   NEXT;
 124 }
 125
 126 VM_DEFINE_INSTRUCTION (11, make_int8_1, "make-int8:1", 0, 0, 1)
 127 {
 128   PUSH (SCM_I_MAKINUM (1));
 129   NEXT;
 130 }
 131
 132 VM_DEFINE_INSTRUCTION (12, make_int16, "make-int16", 2, 0, 1)
 133 {
 134   int h = FETCH ();
 135   int l = FETCH ();
 136   PUSH (SCM_I_MAKINUM ((signed short) (h << 8) + l));
 137   NEXT;
 138 }
 139
 140 VM_DEFINE_INSTRUCTION (13, make_int64, "make-int64", 8, 0, 1)
 141 {
 142   scm_t_uint64 v = 0;
 143   v += FETCH ();
 144   v <<= 8; v += FETCH ();
 145   v <<= 8; v += FETCH ();
 146   v <<= 8; v += FETCH ();
 147   v <<= 8; v += FETCH ();
 148   v <<= 8; v += FETCH ();
 149   v <<= 8; v += FETCH ();
 150   v <<= 8; v += FETCH ();
 151   PUSH (scm_from_int64 ((scm_t_int64) v));
 152   NEXT;
 153 }
 154
 155 VM_DEFINE_INSTRUCTION (14, make_uint64, "make-uint64", 8, 0, 1)
 156 {
 157   scm_t_uint64 v = 0;
 158   v += FETCH ();
 159   v <<= 8; v += FETCH ();
 160   v <<= 8; v += FETCH ();
 161   v <<= 8; v += FETCH ();
 162   v <<= 8; v += FETCH ();
 163   v <<= 8; v += FETCH ();
 164   v <<= 8; v += FETCH ();
 165   v <<= 8; v += FETCH ();
 166   PUSH (scm_from_uint64 (v));
 167   NEXT;
 168 }
 169
 170 VM_DEFINE_INSTRUCTION (15, make_char8, "make-char8", 1, 0, 1)
 171 {
 172   scm_t_uint8 v = 0;
 173   v = FETCH ();
 174
 175   PUSH (SCM_MAKE_CHAR (v));
 176   /* Don't simplify this to PUSH (SCM_MAKE_CHAR (FETCH ())).  The
 177      contents of SCM_MAKE_CHAR may be evaluated more than once,
 178      resulting in a double fetch.  */
 179   NEXT;
 180 }
 181
 182 VM_DEFINE_INSTRUCTION (16, make_char32, "make-char32", 4, 0, 1)
 183 {
 184   scm_t_wchar v = 0;
 185   v += FETCH ();
 186   v <<= 8; v += FETCH ();
 187   v <<= 8; v += FETCH ();
 188   v <<= 8; v += FETCH ();
 189   PUSH (SCM_MAKE_CHAR (v));
 190   NEXT;
 191 }
 192
 193
 194
 195 VM_DEFINE_INSTRUCTION (17, list, "list", 2, -1, 1)
 196 {
 197   unsigned h = FETCH ();
 198   unsigned l = FETCH ();
 199   unsigned len = ((h << 8) + l);
 200   POP_LIST (len);
 201   NEXT;
 202 }
 203
 204 VM_DEFINE_INSTRUCTION (18, vector, "vector", 2, -1, 1)
 205 {
 206   unsigned h = FETCH ();
 207   unsigned l = FETCH ();
 208   unsigned len = ((h << 8) + l);
 209   SCM vect;
 210
 211   SYNC_REGISTER ();
 212   sp++; sp -= len;
 213   CHECK_UNDERFLOW ();
 214   vect = scm_make_vector (scm_from_uint (len), SCM_BOOL_F);
 215   memcpy (SCM_I_VECTOR_WELTS(vect), sp, sizeof(SCM) * len);
 216   NULLSTACK (len);
 217   *sp = vect;
 218
 219   NEXT;
 220 }
 221
 222 \f
 223 /*
 224  * Variable access
 225  */
 226
 227 #define OBJECT_REF(i)           objects[i]
 228 #define OBJECT_SET(i,o)         objects[i] = o
 229
 230 #define LOCAL_REF(i)            SCM_FRAME_VARIABLE (fp, i)
 231 #define LOCAL_SET(i,o)          SCM_FRAME_VARIABLE (fp, i) = o
 232
 233 /* For the variable operations, we _must_ obviously avoid function calls to
 234    `scm_variable_ref ()', `scm_variable_bound_p ()' and friends which do
 235    nothing more than the corresponding macros.  */
 236 #define VARIABLE_REF(v)         SCM_VARIABLE_REF (v)
 237 #define VARIABLE_SET(v,o)       SCM_VARIABLE_SET (v, o)
 238 #define VARIABLE_BOUNDP(v)      (VARIABLE_REF (v) != SCM_UNDEFINED)
 239
 240 #define FREE_VARIABLE_REF(i)    free_vars[i]
 241
 242 /* ref */
 243
 244 VM_DEFINE_INSTRUCTION (19, object_ref, "object-ref", 1, 0, 1)
 245 {
 246   register unsigned objnum = FETCH ();
 247   CHECK_OBJECT (objnum);
 248   PUSH (OBJECT_REF (objnum));
 249   NEXT;
 250 }
 251
 252 /* FIXME: necessary? elt 255 of the vector could be a vector... */
 253 VM_DEFINE_INSTRUCTION (20, long_object_ref, "long-object-ref", 2, 0, 1)
 254 {
 255   unsigned int objnum = FETCH ();
 256   objnum <<= 8;
 257   objnum += FETCH ();
 258   CHECK_OBJECT (objnum);
 259   PUSH (OBJECT_REF (objnum));
 260   NEXT;
 261 }
 262
 263 VM_DEFINE_INSTRUCTION (21, local_ref, "local-ref", 1, 0, 1)
 264 {
 265   PUSH (LOCAL_REF (FETCH ()));
 266   ASSERT_BOUND (*sp);
 267   NEXT;
 268 }
 269
 270 VM_DEFINE_INSTRUCTION (22, long_local_ref, "long-local-ref", 2, 0, 1)
 271 {
 272   unsigned int i = FETCH ();
 273   i <<= 8;
 274   i += FETCH ();
 275   PUSH (LOCAL_REF (i));
 276   ASSERT_BOUND (*sp);
 277   NEXT;
 278 }
 279
 280 VM_DEFINE_INSTRUCTION (23, local_bound, "local-bound?", 1, 0, 1)
 281 {
 282   if (LOCAL_REF (FETCH ()) == SCM_UNDEFINED)
 283     PUSH (SCM_BOOL_F);
 284   else
 285     PUSH (SCM_BOOL_T);
 286   NEXT;
 287 }
 288
 289 VM_DEFINE_INSTRUCTION (24, long_local_bound, "long-local-bound?", 2, 0, 1)
 290 {
 291   unsigned int i = FETCH ();
 292   i <<= 8;
 293   i += FETCH ();
 294   if (LOCAL_REF (i) == SCM_UNDEFINED)
 295     PUSH (SCM_BOOL_F);
 296   else
 297     PUSH (SCM_BOOL_T);
 298   NEXT;
 299 }
 300
 301 VM_DEFINE_INSTRUCTION (25, variable_ref, "variable-ref", 0, 0, 1)
 302 {
 303   SCM x = *sp;
 304
 305   if (!VARIABLE_BOUNDP (x))
 306     {
 307       finish_args = scm_list_1 (x);
 308       /* Was: finish_args = SCM_LIST1 (SCM_CAR (x)); */
 309       goto vm_error_unbound;
 310     }
 311   else
 312     {
 313       SCM o = VARIABLE_REF (x);
 314       *sp = o;
 315     }
 316
 317   NEXT;
 318 }
 319
 320 VM_DEFINE_INSTRUCTION (26, variable_bound, "variable-bound?", 0, 0, 1)
 321 {
 322   if (VARIABLE_BOUNDP (*sp))
 323     *sp = SCM_BOOL_T;
 324   else
 325     *sp = SCM_BOOL_F;
 326   NEXT;
 327 }
 328
 329 VM_DEFINE_INSTRUCTION (27, toplevel_ref, "toplevel-ref", 1, 0, 1)
 330 {
 331   unsigned objnum = FETCH ();
 332   SCM what;
 333   CHECK_OBJECT (objnum);
 334   what = OBJECT_REF (objnum);
 335
 336   if (!SCM_VARIABLEP (what))
 337     {
 338       SYNC_REGISTER ();
 339       what = resolve_variable (what, scm_program_module (program));
 340       if (!VARIABLE_BOUNDP (what))
 341         {
 342           finish_args = scm_list_1 (what);
 343           goto vm_error_unbound;
 344         }
 345       OBJECT_SET (objnum, what);
 346     }
 347
 348   PUSH (VARIABLE_REF (what));
 349   NEXT;
 350 }
 351
 352 VM_DEFINE_INSTRUCTION (28, long_toplevel_ref, "long-toplevel-ref", 2, 0, 1)
 353 {
 354   SCM what;
 355   unsigned int objnum = FETCH ();
 356   objnum <<= 8;
 357   objnum += FETCH ();
 358   CHECK_OBJECT (objnum);
 359   what = OBJECT_REF (objnum);
 360
 361   if (!SCM_VARIABLEP (what))
 362     {
 363       SYNC_REGISTER ();
 364       what = resolve_variable (what, scm_program_module (program));
 365       if (!VARIABLE_BOUNDP (what))
 366         {
 367           finish_args = scm_list_1 (what);
 368           goto vm_error_unbound;
 369         }
 370       OBJECT_SET (objnum, what);
 371     }
 372
 373   PUSH (VARIABLE_REF (what));
 374   NEXT;
 375 }
 376
 377 /* set */
 378
 379 VM_DEFINE_INSTRUCTION (29, local_set, "local-set", 1, 1, 0)
 380 {
 381   LOCAL_SET (FETCH (), *sp);
 382   DROP ();
 383   NEXT;
 384 }
 385
 386 VM_DEFINE_INSTRUCTION (30, long_local_set, "long-local-set", 2, 1, 0)
 387 {
 388   unsigned int i = FETCH ();
 389   i <<= 8;
 390   i += FETCH ();
 391   LOCAL_SET (i, *sp);
 392   DROP ();
 393   NEXT;
 394 }
 395
 396 VM_DEFINE_INSTRUCTION (31, variable_set, "variable-set", 0, 1, 0)
 397 {
 398   VARIABLE_SET (sp[0], sp[-1]);
 399   DROPN (2);
 400   NEXT;
 401 }
 402
 403 VM_DEFINE_INSTRUCTION (32, toplevel_set, "toplevel-set", 1, 1, 0)
 404 {
 405   unsigned objnum = FETCH ();
 406   SCM what;
 407   CHECK_OBJECT (objnum);
 408   what = OBJECT_REF (objnum);
 409
 410   if (!SCM_VARIABLEP (what))
 411     {
 412       SYNC_BEFORE_GC ();
 413       what = resolve_variable (what, scm_program_module (program));
 414       OBJECT_SET (objnum, what);
 415     }
 416
 417   VARIABLE_SET (what, *sp);
 418   DROP ();
 419   NEXT;
 420 }
 421
 422 VM_DEFINE_INSTRUCTION (33, long_toplevel_set, "long-toplevel-set", 2, 1, 0)
 423 {
 424   SCM what;
 425   unsigned int objnum = FETCH ();
 426   objnum <<= 8;
 427   objnum += FETCH ();
 428   CHECK_OBJECT (objnum);
 429   what = OBJECT_REF (objnum);
 430
 431   if (!SCM_VARIABLEP (what))
 432     {
 433       SYNC_BEFORE_GC ();
 434       what = resolve_variable (what, scm_program_module (program));
 435       OBJECT_SET (objnum, what);
 436     }
 437
 438   VARIABLE_SET (what, *sp);
 439   DROP ();
 440   NEXT;
 441 }
 442
 443 \f
 444 /*
 445  * branch and jump
 446  */
 447
 448 /* offset must be at least 24 bits wide, and signed */
 449 #define FETCH_OFFSET(offset)                    \
 450 {                                               \
 451   offset = FETCH () << 16;                      \
 452   offset += FETCH () << 8;                      \
 453   offset += FETCH ();                           \
 454   offset -= (offset & (1<<23)) << 1;            \
 455 }
 456
 457 #define BR(p)                                   \
 458 {                                               \
 459   scm_t_int32 offset;                           \
 460   FETCH_OFFSET (offset);                        \
 461   if (p)                                        \
 462     ip += offset;                               \
 463   NULLSTACK (1);                                \
 464   DROP ();                                      \
 465   NEXT;                                         \
 466 }
 467
 468 VM_DEFINE_INSTRUCTION (34, br, "br", 3, 0, 0)
 469 {
 470   scm_t_int32 offset;
 471   FETCH_OFFSET (offset);
 472   ip += offset;
 473   NEXT;
 474 }
 475
 476 VM_DEFINE_INSTRUCTION (35, br_if, "br-if", 3, 0, 0)
 477 {
 478   BR (scm_is_true_and_not_nil (*sp));
 479 }
 480
 481 VM_DEFINE_INSTRUCTION (36, br_if_not, "br-if-not", 3, 0, 0)
 482 {
 483   BR (scm_is_false_or_nil (*sp));
 484 }
 485
 486 VM_DEFINE_INSTRUCTION (37, br_if_eq, "br-if-eq", 3, 0, 0)
 487 {
 488   sp--; /* underflow? */
 489   BR (scm_is_eq (sp[0], sp[1]));
 490 }
 491
 492 VM_DEFINE_INSTRUCTION (38, br_if_not_eq, "br-if-not-eq", 3, 0, 0)
 493 {
 494   sp--; /* underflow? */
 495   BR (!scm_is_eq (sp[0], sp[1]));
 496 }
 497
 498 VM_DEFINE_INSTRUCTION (39, br_if_null, "br-if-null", 3, 0, 0)
 499 {
 500   BR (scm_is_null_or_nil (*sp));
 501 }
 502
 503 VM_DEFINE_INSTRUCTION (40, br_if_not_null, "br-if-not-null", 3, 0, 0)
 504 {
 505   BR (!scm_is_null_or_nil (*sp));
 506 }
 507
 508 \f
 509 /*
 510  * Subprogram call
 511  */
 512
 513 VM_DEFINE_INSTRUCTION (41, br_if_nargs_ne, "br-if-nargs-ne", 5, 0, 0)
 514 {
 515   scm_t_ptrdiff n;
 516   scm_t_int32 offset;
 517   n = FETCH () << 8;
 518   n += FETCH ();
 519   FETCH_OFFSET (offset);
 520   if (sp - (fp - 1) != n)
 521     ip += offset;
 522   NEXT;
 523 }
 524
 525 VM_DEFINE_INSTRUCTION (42, br_if_nargs_lt, "br-if-nargs-lt", 5, 0, 0)
 526 {
 527   scm_t_ptrdiff n;
 528   scm_t_int32 offset;
 529   n = FETCH () << 8;
 530   n += FETCH ();
 531   FETCH_OFFSET (offset);
 532   if (sp - (fp - 1) < n)
 533     ip += offset;
 534   NEXT;
 535 }
 536
 537 VM_DEFINE_INSTRUCTION (43, br_if_nargs_gt, "br-if-nargs-gt", 5, 0, 0)
 538 {
 539   scm_t_ptrdiff n;
 540   scm_t_int32 offset;
 541
 542   n = FETCH () << 8;
 543   n += FETCH ();
 544   FETCH_OFFSET (offset);
 545   if (sp - (fp - 1) > n)
 546     ip += offset;
 547   NEXT;
 548 }
 549
 550 VM_DEFINE_INSTRUCTION (44, assert_nargs_ee, "assert-nargs-ee", 2, 0, 0)
 551 {
 552   scm_t_ptrdiff n;
 553   n = FETCH () << 8;
 554   n += FETCH ();
 555   if (sp - (fp - 1) != n)
 556     goto vm_error_wrong_num_args;
 557   NEXT;
 558 }
 559
 560 VM_DEFINE_INSTRUCTION (45, assert_nargs_ge, "assert-nargs-ge", 2, 0, 0)
 561 {
 562   scm_t_ptrdiff n;
 563   n = FETCH () << 8;
 564   n += FETCH ();
 565   if (sp - (fp - 1) < n)
 566     goto vm_error_wrong_num_args;
 567   NEXT;
 568 }
 569
 570 VM_DEFINE_INSTRUCTION (46, bind_optionals, "bind-optionals", 2, -1, -1)
 571 {
 572   scm_t_ptrdiff n;
 573   n = FETCH () << 8;
 574   n += FETCH ();
 575   while (sp - (fp - 1) < n)
 576     PUSH (SCM_UNDEFINED);
 577   NEXT;
 578 }
 579
 580 VM_DEFINE_INSTRUCTION (47, bind_optionals_shuffle, "bind-optionals/shuffle", 6, -1, -1)
 581 {
 582   SCM *walk;
 583   scm_t_ptrdiff nreq, nreq_and_opt, ntotal;
 584   nreq = FETCH () << 8;
 585   nreq += FETCH ();
 586   nreq_and_opt = FETCH () << 8;
 587   nreq_and_opt += FETCH ();
 588   ntotal = FETCH () << 8;
 589   ntotal += FETCH ();
 590
 591   /* look in optionals for first keyword or last positional */
 592   /* starting after the last required positional arg */
 593   walk = fp + nreq;
 594   while (/* while we have args */
 595          walk <= sp
 596          /* and we still have positionals to fill */
 597          && walk - fp < nreq_and_opt
 598          /* and we haven't reached a keyword yet */
 599          && !scm_is_keyword (*walk))
 600     /* bind this optional arg (by leaving it in place) */
 601     walk++;
 602   /* now shuffle up, from walk to ntotal */
 603   {
 604     scm_t_ptrdiff nshuf = sp - walk + 1, i;
 605     sp = (fp - 1) + ntotal + nshuf;
 606     CHECK_OVERFLOW ();
 607     for (i = 0; i < nshuf; i++)
 608       sp[-i] = walk[nshuf-i-1];
 609   }
 610   /* and fill optionals & keyword args with SCM_UNDEFINED */
 611   while (walk <= (fp - 1) + ntotal)
 612     *walk++ = SCM_UNDEFINED;
 613
 614   NEXT;
 615 }
 616
 617 /* Flags that determine whether other keywords are allowed, and whether a
 618    rest argument is expected.  These values must match those used by the
 619    glil->assembly compiler.  */
 620 #define F_ALLOW_OTHER_KEYS  1
 621 #define F_REST              2
 622
 623 VM_DEFINE_INSTRUCTION (48, bind_kwargs, "bind-kwargs", 5, 0, 0)
 624 {
 625   scm_t_uint16 idx;
 626   scm_t_ptrdiff nkw;
 627   int kw_and_rest_flags;
 628   SCM kw;
 629   idx = FETCH () << 8;
 630   idx += FETCH ();
 631   /* XXX: We don't actually use NKW.  */
 632   nkw = FETCH () << 8;
 633   nkw += FETCH ();
 634   kw_and_rest_flags = FETCH ();
 635
 636   if (!(kw_and_rest_flags & F_REST)
 637       && ((sp - (fp - 1) - nkw) % 2))
 638     goto vm_error_kwargs_length_not_even;
 639
 640   CHECK_OBJECT (idx);
 641   kw = OBJECT_REF (idx);
 642
 643   /* Switch NKW to be a negative index below SP.  */
 644   for (nkw = -(sp - (fp - 1) - nkw) + 1; nkw < 0; nkw++)
 645     {
 646       SCM walk;
 647
 648       if (scm_is_keyword (sp[nkw]))
 649         {
 650           for (walk = kw; scm_is_pair (walk); walk = SCM_CDR (walk))
 651             {
 652               if (scm_is_eq (SCM_CAAR (walk), sp[nkw]))
 653                 {
 654                   SCM si = SCM_CDAR (walk);
 655                   LOCAL_SET (SCM_I_INUMP (si) ? SCM_I_INUM (si) : scm_to_long (si),
 656                              sp[nkw + 1]);
 657                   break;
 658                 }
 659             }
 660           if (!(kw_and_rest_flags & F_ALLOW_OTHER_KEYS) && !scm_is_pair (walk))
 661             goto vm_error_kwargs_unrecognized_keyword;
 662
 663           nkw++;
 664         }
 665       else if (!(kw_and_rest_flags & F_REST))
 666         goto vm_error_kwargs_invalid_keyword;
 667     }
 668
 669   NEXT;
 670 }
 671
 672 #undef F_ALLOW_OTHER_KEYS
 673 #undef F_REST
 674
 675
 676 VM_DEFINE_INSTRUCTION (49, push_rest, "push-rest", 2, -1, -1)
 677 {
 678   scm_t_ptrdiff n;
 679   SCM rest = SCM_EOL;
 680   n = FETCH () << 8;
 681   n += FETCH ();
 682   while (sp - (fp - 1) > n)
 683     /* No need to check for underflow. */
 684     CONS (rest, *sp--, rest);
 685   PUSH (rest);
 686   NEXT;
 687 }
 688
 689 VM_DEFINE_INSTRUCTION (50, bind_rest, "bind-rest", 4, -1, -1)
 690 {
 691   scm_t_ptrdiff n;
 692   scm_t_uint32 i;
 693   SCM rest = SCM_EOL;
 694   n = FETCH () << 8;
 695   n += FETCH ();
 696   i = FETCH () << 8;
 697   i += FETCH ();
 698   while (sp - (fp - 1) > n)
 699     /* No need to check for underflow. */
 700     CONS (rest, *sp--, rest);
 701   LOCAL_SET (i, rest);
 702   NEXT;
 703 }
 704
 705 VM_DEFINE_INSTRUCTION (51, reserve_locals, "reserve-locals", 2, -1, -1)
 706 {
 707   SCM *old_sp;
 708   scm_t_int32 n;
 709   n = FETCH () << 8;
 710   n += FETCH ();
 711   old_sp = sp;
 712   sp = (fp - 1) + n;
 713
 714   if (old_sp < sp)
 715     {
 716       CHECK_OVERFLOW ();
 717       while (old_sp < sp)
 718         *++old_sp = SCM_UNDEFINED;
 719     }
 720   else
 721     NULLSTACK (old_sp - sp);
 722
 723   NEXT;
 724 }
 725
 726 VM_DEFINE_INSTRUCTION (52, new_frame, "new-frame", 0, 0, 3)
 727 {
 728   /* NB: if you change this, see frames.c:vm-frame-num-locals */
 729   /* and frames.h, vm-engine.c, etc of course */
 730   PUSH ((SCM)fp); /* dynamic link */
 731   PUSH (0);  /* mvra */
 732   PUSH (0);  /* ra */
 733   NEXT;
 734 }
 735
 736 VM_DEFINE_INSTRUCTION (53, call, "call", 1, -1, 1)
 737 {
 738   SCM x;
 739   nargs = FETCH ();
 740
 741  vm_call:
 742   x = sp[-nargs];
 743
 744   SYNC_REGISTER ();
 745   SCM_TICK;     /* allow interrupt here */
 746
 747   /*
 748    * Subprogram call
 749    */
 750   if (SCM_PROGRAM_P (x))
 751     {
 752       program = x;
 753       CACHE_PROGRAM ();
 754       fp = sp - nargs + 1;
 755       ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0);
 756       ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0);
 757       SCM_FRAME_SET_RETURN_ADDRESS (fp, ip);
 758       SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, 0);
 759       ip = bp->base;
 760       ENTER_HOOK ();
 761       APPLY_HOOK ();
 762       NEXT;
 763     }
 764   if (SCM_STRUCTP (x) && SCM_STRUCT_APPLICABLE_P (x))
 765     {
 766       sp[-nargs] = SCM_STRUCT_PROCEDURE (x);
 767       goto vm_call;
 768     }
 769   /*
 770    * Other interpreted or compiled call
 771    */
 772   if (!scm_is_false (scm_procedure_p (x)))
 773     {
 774       SCM args;
 775       /* At this point, the stack contains the frame, the procedure and each one
 776          of its arguments. */
 777       POP_LIST (nargs);
 778       POP (args);
 779       DROP (); /* drop the procedure */
 780       DROP_FRAME ();
 781
 782       SYNC_REGISTER ();
 783       PUSH (scm_apply (x, args, SCM_EOL));
 784       NULLSTACK_FOR_NONLOCAL_EXIT ();
 785       if (SCM_UNLIKELY (SCM_VALUESP (*sp)))
 786         {
 787           /* truncate values */
 788           SCM values;
 789           POP (values);
 790           values = scm_struct_ref (values, SCM_INUM0);
 791           if (scm_is_null (values))
 792             goto vm_error_not_enough_values;
 793           PUSH (SCM_CAR (values));
 794         }
 795       NEXT;
 796     }
 797
 798   program = x;
 799   goto vm_error_wrong_type_apply;
 800 }
 801
 802 VM_DEFINE_INSTRUCTION (54, goto_args, "goto/args", 1, -1, 1)
 803 {
 804   register SCM x;
 805   nargs = FETCH ();
 806  vm_goto_args:
 807   x = sp[-nargs];
 808
 809   SYNC_REGISTER ();
 810   SCM_TICK;     /* allow interrupt here */
 811
 812   /*
 813    * Tail call
 814    */
 815   if (SCM_PROGRAM_P (x))
 816     {
 817       int i;
 818 #ifdef VM_ENABLE_STACK_NULLING
 819       SCM *old_sp = sp;
 820       CHECK_STACK_LEAK ();
 821 #endif
 822
 823       EXIT_HOOK ();
 824
 825       /* switch programs */
 826       program = x;
 827       CACHE_PROGRAM ();
 828       /* shuffle down the program and the arguments */
 829       for (i = -1, sp = sp - nargs + 1; i < nargs; i++)
 830         SCM_FRAME_STACK_ADDRESS (fp)[i] = sp[i];
 831
 832       sp = fp + i - 1;
 833
 834       NULLSTACK (old_sp - sp);
 835
 836       ip = bp->base;
 837
 838       ENTER_HOOK ();
 839       APPLY_HOOK ();
 840       NEXT;
 841     }
 842   if (SCM_STRUCTP (x) && SCM_STRUCT_APPLICABLE_P (x))
 843     {
 844       sp[-nargs] = SCM_STRUCT_PROCEDURE (x);
 845       goto vm_goto_args;
 846     }
 847
 848   /*
 849    * Other interpreted or compiled call
 850    */
 851   if (!scm_is_false (scm_procedure_p (x)))
 852     {
 853       SCM args;
 854       POP_LIST (nargs);
 855       POP (args);
 856
 857       SYNC_REGISTER ();
 858       *sp = scm_apply (x, args, SCM_EOL);
 859       NULLSTACK_FOR_NONLOCAL_EXIT ();
 860
 861       if (SCM_UNLIKELY (SCM_VALUESP (*sp)))
 862         {
 863           /* multiple values returned to continuation */
 864           SCM values;
 865           POP (values);
 866           values = scm_struct_ref (values, SCM_INUM0);
 867           nvalues = scm_ilength (values);
 868           PUSH_LIST (values, scm_is_null);
 869           goto vm_return_values;
 870         }
 871       else
 872         goto vm_return;
 873     }
 874
 875   program = x;
 876
 877   goto vm_error_wrong_type_apply;
 878 }
 879
 880 VM_DEFINE_INSTRUCTION (55, goto_nargs, "goto/nargs", 0, 0, 1)
 881 {
 882   SCM x;
 883   POP (x);
 884   nargs = scm_to_int (x);
 885   /* FIXME: should truncate values? */
 886   goto vm_goto_args;
 887 }
 888
 889 VM_DEFINE_INSTRUCTION (56, call_nargs, "call/nargs", 0, 0, 1)
 890 {
 891   SCM x;
 892   POP (x);
 893   nargs = scm_to_int (x);
 894   /* FIXME: should truncate values? */
 895   goto vm_call;
 896 }
 897
 898 VM_DEFINE_INSTRUCTION (57, mv_call, "mv-call", 4, -1, 1)
 899 {
 900   SCM x;
 901   scm_t_int32 offset;
 902   scm_t_uint8 *mvra;
 903
 904   nargs = FETCH ();
 905   FETCH_OFFSET (offset);
 906   mvra = ip + offset;
 907
 908  vm_mv_call:
 909   x = sp[-nargs];
 910
 911   /*
 912    * Subprogram call
 913    */
 914   if (SCM_PROGRAM_P (x))
 915     {
 916       program = x;
 917       CACHE_PROGRAM ();
 918       fp = sp - nargs + 1;
 919       ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0);
 920       ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0);
 921       SCM_FRAME_SET_RETURN_ADDRESS (fp, ip);
 922       SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, mvra);
 923       ip = bp->base;
 924       ENTER_HOOK ();
 925       APPLY_HOOK ();
 926       NEXT;
 927     }
 928   if (SCM_STRUCTP (x) && SCM_STRUCT_APPLICABLE_P (x))
 929     {
 930       sp[-nargs] = SCM_STRUCT_PROCEDURE (x);
 931       goto vm_mv_call;
 932     }
 933   /*
 934    * Other interpreted or compiled call
 935    */
 936   if (!scm_is_false (scm_procedure_p (x)))
 937     {
 938       SCM args;
 939       /* At this point, the stack contains the procedure and each one of its
 940          arguments.  */
 941       POP_LIST (nargs);
 942       POP (args);
 943       DROP (); /* drop the procedure */
 944       DROP_FRAME ();
 945
 946       SYNC_REGISTER ();
 947       PUSH (scm_apply (x, args, SCM_EOL));
 948       NULLSTACK_FOR_NONLOCAL_EXIT ();
 949       if (SCM_VALUESP (*sp))
 950         {
 951           SCM values, len;
 952           POP (values);
 953           values = scm_struct_ref (values, SCM_INUM0);
 954           len = scm_length (values);
 955           PUSH_LIST (values, scm_is_null);
 956           PUSH (len);
 957           ip = mvra;
 958         }
 959       NEXT;
 960     }
 961
 962   program = x;
 963   goto vm_error_wrong_type_apply;
 964 }
 965
 966 VM_DEFINE_INSTRUCTION (58, apply, "apply", 1, -1, 1)
 967 {
 968   int len;
 969   SCM ls;
 970   POP (ls);
 971
 972   nargs = FETCH ();
 973   ASSERT (nargs >= 2);
 974
 975   len = scm_ilength (ls);
 976   if (len < 0)
 977     goto vm_error_wrong_type_arg;
 978
 979   PUSH_LIST (ls, SCM_NULL_OR_NIL_P);
 980
 981   nargs += len - 2;
 982   goto vm_call;
 983 }
 984
 985 VM_DEFINE_INSTRUCTION (59, goto_apply, "goto/apply", 1, -1, 1)
 986 {
 987   int len;
 988   SCM ls;
 989   POP (ls);
 990
 991   nargs = FETCH ();
 992   ASSERT (nargs >= 2);
 993
 994   len = scm_ilength (ls);
 995   if (len < 0)
 996     goto vm_error_wrong_type_arg;
 997
 998   PUSH_LIST (ls, SCM_NULL_OR_NIL_P);
 999
1000   nargs += len - 2;
1001   goto vm_goto_args;
1002 }
1003
1004 VM_DEFINE_INSTRUCTION (60, call_cc, "call/cc", 0, 1, 1)
1005 {
1006   int first;
1007   SCM proc, cont;
1008   POP (proc);
1009   SYNC_ALL ();
1010   cont = scm_make_continuation (&first);
1011   if (first)
1012     {
1013       PUSH ((SCM)fp); /* dynamic link */
1014       PUSH (0);  /* mvra */
1015       PUSH (0);  /* ra */
1016       PUSH (proc);
1017       PUSH (cont);
1018       nargs = 1;
1019       goto vm_call;
1020     }
1021   ASSERT (sp == vp->sp);
1022   ASSERT (fp == vp->fp);
1023   else if (SCM_VALUESP (cont))
1024     {
1025       /* multiple values returned to continuation */
1026       SCM values;
1027       values = scm_struct_ref (cont, SCM_INUM0);
1028       if (scm_is_null (values))
1029         goto vm_error_no_values;
1030       /* non-tail context does not accept multiple values? */
1031       PUSH (SCM_CAR (values));
1032       NEXT;
1033     }
1034   else
1035     {
1036       PUSH (cont);
1037       NEXT;
1038     }
1039 }
1040
1041 VM_DEFINE_INSTRUCTION (61, goto_cc, "goto/cc", 0, 1, 1)
1042 {
1043   int first;
1044   SCM proc, cont;
1045   POP (proc);
1046   SYNC_ALL ();
1047   cont = scm_make_continuation (&first);
1048   ASSERT (sp == vp->sp);
1049   ASSERT (fp == vp->fp);
1050   if (first)
1051     {
1052       PUSH (proc);
1053       PUSH (cont);
1054       nargs = 1;
1055       goto vm_goto_args;
1056     }
1057   else if (SCM_VALUESP (cont))
1058     {
1059       /* multiple values returned to continuation */
1060       SCM values;
1061       values = scm_struct_ref (cont, SCM_INUM0);
1062       nvalues = scm_ilength (values);
1063       PUSH_LIST (values, scm_is_null);
1064       goto vm_return_values;
1065     }
1066   else
1067     {
1068       PUSH (cont);
1069       goto vm_return;
1070     }
1071 }
1072
1073 VM_DEFINE_INSTRUCTION (62, return, "return", 0, 1, 1)
1074 {
1075  vm_return:
1076   EXIT_HOOK ();
1077   RETURN_HOOK ();
1078   SYNC_REGISTER ();
1079   SCM_TICK;     /* allow interrupt here */
1080   {
1081     SCM ret;
1082
1083     POP (ret);
1084
1085 #ifdef VM_ENABLE_STACK_NULLING
1086     SCM *old_sp = sp;
1087 #endif
1088
1089     /* Restore registers */
1090     sp = SCM_FRAME_LOWER_ADDRESS (fp);
1091     ip = SCM_FRAME_RETURN_ADDRESS (fp);
1092     fp = SCM_FRAME_DYNAMIC_LINK (fp);
1093
1094 #ifdef VM_ENABLE_STACK_NULLING
1095     NULLSTACK (old_sp - sp);
1096 #endif
1097
1098     /* Set return value (sp is already pushed) */
1099     *sp = ret;
1100   }
1101
1102   /* Restore the last program */
1103   program = SCM_FRAME_PROGRAM (fp);
1104   CACHE_PROGRAM ();
1105   CHECK_IP ();
1106   NEXT;
1107 }
1108
1109 VM_DEFINE_INSTRUCTION (63, return_values, "return/values", 1, -1, -1)
1110 {
1111   /* nvalues declared at top level, because for some reason gcc seems to think
1112      that perhaps it might be used without declaration. Fooey to that, I say. */
1113   nvalues = FETCH ();
1114  vm_return_values:
1115   EXIT_HOOK ();
1116   RETURN_HOOK ();
1117
1118   if (nvalues != 1 && SCM_FRAME_MV_RETURN_ADDRESS (fp))
1119     {
1120       /* A multiply-valued continuation */
1121       SCM *vals = sp - nvalues;
1122       int i;
1123       /* Restore registers */
1124       sp = SCM_FRAME_LOWER_ADDRESS (fp) - 1;
1125       ip = SCM_FRAME_MV_RETURN_ADDRESS (fp);
1126       fp = SCM_FRAME_DYNAMIC_LINK (fp);
1127
1128       /* Push return values, and the number of values */
1129       for (i = 0; i < nvalues; i++)
1130         *++sp = vals[i+1];
1131       *++sp = SCM_I_MAKINUM (nvalues);
1132
1133       /* Finally null the end of the stack */
1134       NULLSTACK (vals + nvalues - sp);
1135     }
1136   else if (nvalues >= 1)
1137     {
1138       /* Multiple values for a single-valued continuation -- here's where I
1139          break with guile tradition and try and do something sensible. (Also,
1140          this block handles the single-valued return to an mv
1141          continuation.) */
1142       SCM *vals = sp - nvalues;
1143       /* Restore registers */
1144       sp = SCM_FRAME_LOWER_ADDRESS (fp) - 1;
1145       ip = SCM_FRAME_RETURN_ADDRESS (fp);
1146       fp = SCM_FRAME_DYNAMIC_LINK (fp);
1147
1148       /* Push first value */
1149       *++sp = vals[1];
1150
1151       /* Finally null the end of the stack */
1152       NULLSTACK (vals + nvalues - sp);
1153     }
1154   else
1155     goto vm_error_no_values;
1156
1157   /* Restore the last program */
1158   program = SCM_FRAME_PROGRAM (fp);
1159   CACHE_PROGRAM ();
1160   CHECK_IP ();
1161   NEXT;
1162 }
1163
1164 VM_DEFINE_INSTRUCTION (64, return_values_star, "return/values*", 1, -1, -1)
1165 {
1166   SCM l;
1167
1168   nvalues = FETCH ();
1169   ASSERT (nvalues >= 1);
1170
1171   nvalues--;
1172   POP (l);
1173   while (scm_is_pair (l))
1174     {
1175       PUSH (SCM_CAR (l));
1176       l = SCM_CDR (l);
1177       nvalues++;
1178     }
1179   if (SCM_UNLIKELY (!SCM_NULL_OR_NIL_P (l))) {
1180     finish_args = scm_list_1 (l);
1181     goto vm_error_improper_list;
1182   }
1183
1184   goto vm_return_values;
1185 }
1186
1187 VM_DEFINE_INSTRUCTION (65, truncate_values, "truncate-values", 2, -1, -1)
1188 {
1189   SCM x;
1190   int nbinds, rest;
1191   POP (x);
1192   nvalues = scm_to_int (x);
1193   nbinds = FETCH ();
1194   rest = FETCH ();
1195
1196   if (rest)
1197     nbinds--;
1198
1199   if (nvalues < nbinds)
1200     goto vm_error_not_enough_values;
1201
1202   if (rest)
1203     POP_LIST (nvalues - nbinds);
1204   else
1205     DROPN (nvalues - nbinds);
1206
1207   NEXT;
1208 }
1209
1210 VM_DEFINE_INSTRUCTION (66, box, "box", 1, 1, 0)
1211 {
1212   SCM val;
1213   POP (val);
1214   SYNC_BEFORE_GC ();
1215   LOCAL_SET (FETCH (), scm_cell (scm_tc7_variable, SCM_UNPACK (val)));
1216   NEXT;
1217 }
1218
1219 /* for letrec:
1220    (let ((a *undef*) (b *undef*) ...)
1221      (set! a (lambda () (b ...)))
1222      ...)
1223  */
1224 VM_DEFINE_INSTRUCTION (67, empty_box, "empty-box", 1, 0, 0)
1225 {
1226   SYNC_BEFORE_GC ();
1227   LOCAL_SET (FETCH (),
1228              scm_cell (scm_tc7_variable, SCM_UNPACK (SCM_UNDEFINED)));
1229   NEXT;
1230 }
1231
1232 VM_DEFINE_INSTRUCTION (68, local_boxed_ref, "local-boxed-ref", 1, 0, 1)
1233 {
1234   SCM v = LOCAL_REF (FETCH ());
1235   ASSERT_BOUND_VARIABLE (v);
1236   PUSH (VARIABLE_REF (v));
1237   NEXT;
1238 }
1239
1240 VM_DEFINE_INSTRUCTION (69, local_boxed_set, "local-boxed-set", 1, 1, 0)
1241 {
1242   SCM v, val;
1243   v = LOCAL_REF (FETCH ());
1244   POP (val);
1245   ASSERT_VARIABLE (v);
1246   VARIABLE_SET (v, val);
1247   NEXT;
1248 }
1249
1250 VM_DEFINE_INSTRUCTION (70, free_ref, "free-ref", 1, 0, 1)
1251 {
1252   scm_t_uint8 idx = FETCH ();
1253
1254   CHECK_FREE_VARIABLE (idx);
1255   PUSH (FREE_VARIABLE_REF (idx));
1256   NEXT;
1257 }
1258
1259 /* no free-set -- if a var is assigned, it should be in a box */
1260
1261 VM_DEFINE_INSTRUCTION (71, free_boxed_ref, "free-boxed-ref", 1, 0, 1)
1262 {
1263   SCM v;
1264   scm_t_uint8 idx = FETCH ();
1265   CHECK_FREE_VARIABLE (idx);
1266   v = FREE_VARIABLE_REF (idx);
1267   ASSERT_BOUND_VARIABLE (v);
1268   PUSH (VARIABLE_REF (v));
1269   NEXT;
1270 }
1271
1272 VM_DEFINE_INSTRUCTION (72, free_boxed_set, "free-boxed-set", 1, 1, 0)
1273 {
1274   SCM v, val;
1275   scm_t_uint8 idx = FETCH ();
1276   POP (val);
1277   CHECK_FREE_VARIABLE (idx);
1278   v = FREE_VARIABLE_REF (idx);
1279   ASSERT_BOUND_VARIABLE (v);
1280   VARIABLE_SET (v, val);
1281   NEXT;
1282 }
1283
1284 VM_DEFINE_INSTRUCTION (73, make_closure, "make-closure", 0, 2, 1)
1285 {
1286   SCM vect;
1287   POP (vect);
1288   SYNC_BEFORE_GC ();
1289   /* fixme underflow */
1290   *sp = scm_double_cell (scm_tc7_program, (scm_t_bits)SCM_PROGRAM_OBJCODE (*sp),
1291                          (scm_t_bits)SCM_PROGRAM_OBJTABLE (*sp), (scm_t_bits)vect);
1292   NEXT;
1293 }
1294
1295 VM_DEFINE_INSTRUCTION (74, make_variable, "make-variable", 0, 0, 1)
1296 {
1297   SYNC_BEFORE_GC ();
1298   /* fixme underflow */
1299   PUSH (scm_cell (scm_tc7_variable, SCM_UNPACK (SCM_UNDEFINED)));
1300   NEXT;
1301 }
1302
1303 VM_DEFINE_INSTRUCTION (75, fix_closure, "fix-closure", 2, 0, 1)
1304 {
1305   SCM x, vect;
1306   unsigned int i = FETCH ();
1307   i <<= 8;
1308   i += FETCH ();
1309   POP (vect);
1310   /* FIXME CHECK_LOCAL (i) */
1311   x = LOCAL_REF (i);
1312   /* FIXME ASSERT_PROGRAM (x); */
1313   SCM_SET_CELL_WORD_3 (x, vect);
1314   NEXT;
1315 }
1316
1317 VM_DEFINE_INSTRUCTION (76, define, "define", 0, 0, 2)
1318 {
1319   SCM sym, val;
1320   POP (sym);
1321   POP (val);
1322   SYNC_REGISTER ();
1323   VARIABLE_SET (scm_sym2var (sym, scm_current_module_lookup_closure (),
1324                              SCM_BOOL_T),
1325                 val);
1326   NEXT;
1327 }
1328
1329 VM_DEFINE_INSTRUCTION (77, make_keyword, "make-keyword", 0, 1, 1)
1330 {
1331   CHECK_UNDERFLOW ();
1332   SYNC_REGISTER ();
1333   *sp = scm_symbol_to_keyword (*sp);
1334   NEXT;
1335 }
1336
1337 VM_DEFINE_INSTRUCTION (78, make_symbol, "make-symbol", 0, 1, 1)
1338 {
1339   CHECK_UNDERFLOW ();
1340   SYNC_REGISTER ();
1341   *sp = scm_string_to_symbol (*sp);
1342   NEXT;
1343 }
1344
1345
1346 /*
1347 (defun renumber-ops ()
1348   "start from top of buffer and renumber 'VM_DEFINE_FOO (\n' sequences"
1349   (interactive "")
1350   (save-excursion
1351     (let ((counter -1)) (goto-char (point-min))
1352       (while (re-search-forward "^VM_DEFINE_[^ ]+ (\\([^,]+\\)," (point-max) t)
1353         (replace-match
1354          (number-to-string (setq counter (1+ counter)))
1355           t t nil 1)))))
1356 */
1357 /*
1358   Local Variables:
1359   c-file-style: "gnu"
1360   End:
1361 */