src/vm_system.c

   1 /* Copyright (C) 2000 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 /* This file is included in vm_engine.c */
  43
  44 \f
  45 /*
  46  * Basic operations
  47  */
  48
  49 /* This must be the first instruction! */
  50 VM_DEFINE_INSTRUCTION (nop, "nop", 0, 0, 0)
  51 {
  52   NEXT;
  53 }
  54
  55 VM_DEFINE_INSTRUCTION (halt, "halt", 0, 0, 0)
  56 {
  57   SCM ret = *sp;
  58   vp->time += scm_c_get_internal_run_time () - start_time;
  59   HALT_HOOK ();
  60   FREE_FRAME ();
  61   SYNC_ALL ();
  62   return ret;
  63 }
  64
  65 VM_DEFINE_INSTRUCTION (drop, "drop", 0, 1, 0)
  66 {
  67   DROP ();
  68   NEXT;
  69 }
  70
  71 VM_DEFINE_INSTRUCTION (dup, "dup", 0, 0, 1)
  72 {
  73   PUSH (*sp);
  74   NEXT;
  75 }
  76
  77 \f
  78 /*
  79  * Object creation
  80  */
  81
  82 VM_DEFINE_INSTRUCTION (void, "void", 0, 0, 1)
  83 {
  84   PUSH (SCM_UNSPECIFIED);
  85   NEXT;
  86 }
  87
  88 VM_DEFINE_INSTRUCTION (mark, "mark", 0, 0, 1)
  89 {
  90   PUSH (SCM_UNDEFINED);
  91   NEXT;
  92 }
  93
  94 VM_DEFINE_INSTRUCTION (make_true, "make-true", 0, 0, 1)
  95 {
  96   PUSH (SCM_BOOL_T);
  97   NEXT;
  98 }
  99
 100 VM_DEFINE_INSTRUCTION (make_false, "make-false", 0, 0, 1)
 101 {
 102   PUSH (SCM_BOOL_F);
 103   NEXT;
 104 }
 105
 106 VM_DEFINE_INSTRUCTION (make_eol, "make-eol", 0, 0, 1)
 107 {
 108   PUSH (SCM_EOL);
 109   NEXT;
 110 }
 111
 112 VM_DEFINE_INSTRUCTION (make_int8, "make-int8", 1, 0, 1)
 113 {
 114   PUSH (SCM_MAKINUM ((signed char) FETCH ()));
 115   NEXT;
 116 }
 117
 118 VM_DEFINE_INSTRUCTION (make_int8_0, "make-int8:0", 0, 0, 1)
 119 {
 120   PUSH (SCM_MAKINUM (0));
 121   NEXT;
 122 }
 123
 124 VM_DEFINE_INSTRUCTION (make_int8_1, "make-int8:1", 0, 0, 1)
 125 {
 126   PUSH (SCM_MAKINUM (1));
 127   NEXT;
 128 }
 129
 130 VM_DEFINE_INSTRUCTION (make_int16, "make-int16", 2, 0, 1)
 131 {
 132   int h = FETCH ();
 133   int l = FETCH ();
 134   PUSH (SCM_MAKINUM ((signed short) (h << 8) + l));
 135   NEXT;
 136 }
 137
 138 VM_DEFINE_INSTRUCTION (make_char8, "make-char8", 1, 0, 1)
 139 {
 140   PUSH (SCM_MAKE_CHAR (FETCH ()));
 141   NEXT;
 142 }
 143
 144 \f
 145 /*
 146  * Variable access
 147  */
 148
 149 #define OBJECT_REF(i)           objects[i]
 150 #define OBJECT_SET(i,o)         objects[i] = o
 151
 152 #define LOCAL_REF(i)            SCM_VM_FRAME_VARIABLE (fp, i)
 153 #define LOCAL_SET(i,o)          SCM_VM_FRAME_VARIABLE (fp, i) = o
 154
 155 #define VARIABLE_REF(v)         SCM_CDR (v)
 156 #define VARIABLE_SET(v,o)       SCM_SETCDR (v, o)
 157
 158 /* ref */
 159
 160 VM_DEFINE_INSTRUCTION (object_ref, "object-ref", 1, 0, 1)
 161 {
 162   PUSH (OBJECT_REF (FETCH ()));
 163   NEXT;
 164 }
 165
 166 VM_DEFINE_INSTRUCTION (local_ref, "local-ref", 1, 0, 1)
 167 {
 168   PUSH (LOCAL_REF (FETCH ()));
 169   NEXT;
 170 }
 171
 172 VM_DEFINE_INSTRUCTION (external_ref, "external-ref", 1, 0, 1)
 173 {
 174   unsigned int i;
 175   SCM e = external;
 176   for (i = FETCH (); i; i--)
 177     e = SCM_CDR (e);
 178   PUSH (SCM_CAR (e));
 179   NEXT;
 180 }
 181
 182 VM_DEFINE_INSTRUCTION (variable_ref, "variable-ref", 0, 0, 1)
 183 {
 184   SCM x = *sp;
 185   SCM o = VARIABLE_REF (x);
 186   if (SCM_UNBNDP (o))
 187     {
 188       /* Try autoload here */
 189       err_args = SCM_LIST1 (SCM_CAR (x));
 190       goto vm_error_unbound;
 191     }
 192   *sp = o;
 193   NEXT;
 194 }
 195
 196 /* set */
 197
 198 VM_DEFINE_INSTRUCTION (local_set, "local-set", 1, 1, 0)
 199 {
 200   LOCAL_SET (FETCH (), *sp);
 201   DROP ();
 202   NEXT;
 203 }
 204
 205 VM_DEFINE_INSTRUCTION (external_set, "external-set", 1, 1, 0)
 206 {
 207   unsigned int i;
 208   SCM e = external;
 209   for (i = FETCH (); i; i--)
 210     e = SCM_CDR (e);
 211   SCM_SETCAR (e, *sp);
 212   DROP ();
 213   NEXT;
 214 }
 215
 216 VM_DEFINE_INSTRUCTION (variable_set, "variable-set", 0, 1, 0)
 217 {
 218   VARIABLE_SET (sp[0], sp[1]);
 219   sp += 2;
 220   NEXT;
 221 }
 222
 223 \f
 224 /*
 225  * branch and jump
 226  */
 227
 228 #define BR(p)                                   \
 229 {                                               \
 230   signed char offset = FETCH ();                \
 231   if (p)                                        \
 232     ip += offset;                               \
 233   DROP ();                                      \
 234   NEXT;                                         \
 235 }
 236
 237 VM_DEFINE_INSTRUCTION (br_if, "br-if", 1, 0, 0)
 238 {
 239   BR (!SCM_FALSEP (*sp));
 240 }
 241
 242 VM_DEFINE_INSTRUCTION (br_if_not, "br-if-not", 1, 0, 0)
 243 {
 244   BR (SCM_FALSEP (*sp));
 245 }
 246
 247 VM_DEFINE_INSTRUCTION (br_if_eq, "br-if-eq", 1, 0, 0)
 248 {
 249   BR (SCM_EQ_P (sp[0], sp--[1]));
 250 }
 251
 252 VM_DEFINE_INSTRUCTION (br_if_not_eq, "br-if-not-eq", 1, 0, 0)
 253 {
 254   BR (!SCM_EQ_P (sp[0], sp--[1]));
 255 }
 256
 257 VM_DEFINE_INSTRUCTION (br_if_null, "br-if-null", 1, 0, 0)
 258 {
 259   BR (SCM_NULLP (*sp));
 260 }
 261
 262 VM_DEFINE_INSTRUCTION (br_if_not_null, "br-if-not-null", 1, 0, 0)
 263 {
 264   BR (!SCM_NULLP (*sp));
 265 }
 266
 267 VM_DEFINE_INSTRUCTION (jump, "jump", 1, 0, 0)
 268 {
 269   ip += (signed char) FETCH ();
 270   NEXT;
 271 }
 272
 273 \f
 274 /*
 275  * Subprogram call
 276  */
 277
 278 VM_DEFINE_INSTRUCTION (make_closure, "make-closure", 0, 1, 1)
 279 {
 280   SYNC_BEFORE_GC ();
 281   *sp = scm_c_make_closure (*sp, external);
 282   NEXT;
 283 }
 284
 285 VM_DEFINE_INSTRUCTION (call, "call", 1, -1, 1)
 286 {
 287   POP (program);
 288   nargs = FETCH ();
 289
 290  vm_call:
 291   /*
 292    * Subprogram call
 293    */
 294   if (SCM_PROGRAM_P (program))
 295     {
 296       int i;
 297     vm_call_program:
 298       CACHE_PROGRAM (program);
 299       INIT_ARGS ();
 300       NEW_FRAME ();
 301
 302       /* Init local variables */
 303       for (i = 0; i < bp->nlocs; i++)
 304         LOCAL_SET (i, SCM_UNDEFINED);
 305
 306       /* Create external variables */
 307       for (i = 0; i < bp->nexts; i++)
 308         CONS (external, SCM_UNDEFINED, external);
 309
 310       ENTER_HOOK ();
 311       APPLY_HOOK ();
 312       NEXT;
 313     }
 314   /*
 315    * Function call
 316    */
 317   if (!SCM_FALSEP (scm_procedure_p (program)))
 318     {
 319       POP_LIST (nargs);
 320       *sp = scm_apply (program, *sp, SCM_EOL);
 321       program = SCM_VM_FRAME_PROGRAM (fp);
 322       NEXT;
 323     }
 324   /*
 325    * Continuation call
 326    */
 327   if (SCM_VM_CONT_P (program))
 328     {
 329     vm_call_cc:
 330       /* Check the number of arguments */
 331       if (nargs != 1)
 332         scm_wrong_num_args (program);
 333
 334       /* Reinstate the continuation */
 335       EXIT_HOOK ();
 336       reinstate_vm_cont (vp, program);
 337       CACHE_REGISTER ();
 338       /* We don't need to set the return value here
 339          because it is already on the top of the stack. */
 340       NEXT;
 341     }
 342
 343   goto vm_error_wrong_type_apply;
 344 }
 345
 346 VM_DEFINE_INSTRUCTION (tail_call, "tail-call", 1, -1, 1)
 347 {
 348   SCM x;
 349   POP (x);
 350   nargs = FETCH ();
 351
 352   SCM_TICK;     /* allow interrupt here */
 353
 354   /*
 355    * Tail recursive call
 356    */
 357   if (SCM_EQ_P (x, program))
 358     {
 359       INIT_ARGS ();
 360
 361       /* Move arguments */
 362       if (bp->nargs)
 363         {
 364           int i;
 365           SCM *base = fp + bp->nlocs;
 366           for (i = 0; i < bp->nargs; i++)
 367             base[i] = sp[i];
 368         }
 369
 370       ip = bp->base;
 371       sp = SCM_VM_FRAME_LOWER_ADDRESS (fp);
 372       APPLY_HOOK ();
 373       NEXT;
 374     }
 375   program = x;
 376   /*
 377    * Proper tail call
 378    */
 379   if (SCM_PROGRAM_P (program))
 380     {
 381       int i;
 382       SCM *base = sp;
 383
 384       /* Exit the current frame */
 385       EXIT_HOOK ();
 386       FREE_FRAME ();
 387
 388       /* Move arguments */
 389       sp -= nargs;
 390       for (i = 0; i < nargs; i++)
 391         sp[i] = base[i];
 392
 393       /* Call the program */
 394       goto vm_call_program;
 395     }
 396   /*
 397    * Function call
 398    */
 399   if (!SCM_FALSEP (scm_procedure_p (program)))
 400     {
 401       POP_LIST (nargs);
 402       *sp = scm_apply (program, *sp, SCM_EOL);
 403       program = SCM_VM_FRAME_PROGRAM (fp);
 404       goto vm_return;
 405     }
 406   /*
 407    * Continuation call
 408    */
 409   if (SCM_VM_CONT_P (program))
 410     goto vm_call_cc;
 411
 412   goto vm_error_wrong_type_apply;
 413 }
 414
 415 VM_DEFINE_INSTRUCTION (call_cc, "call/cc", 1, 1, 1)
 416 {
 417   SYNC_BEFORE_GC ();
 418   PUSH (capture_vm_cont (vp));
 419   POP (program);
 420   nargs = 1;
 421   goto vm_call;
 422 }
 423
 424 VM_DEFINE_INSTRUCTION (return, "return", 0, 0, 1)
 425 {
 426   SCM ret;
 427  vm_return:
 428   ret = *sp;
 429   EXIT_HOOK ();
 430   RETURN_HOOK ();
 431   FREE_FRAME ();
 432
 433   /* Cache the last program */
 434   program = SCM_VM_FRAME_PROGRAM (fp);
 435   CACHE_PROGRAM (program);
 436   PUSH (ret);
 437   NEXT;
 438 }
 439
 440 /*
 441   Local Variables:
 442   c-file-style: "gnu"
 443   End:
 444 */