src/bytecode.c

   1 /* Execution of byte code produced by bytecomp.el.
   2    Copyright (C) 1985, 1986, 1987, 1988, 1993 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 hacked on by jwz@lucid.com 17-jun-91
  21   o  added a compile-time switch to turn on simple sanity checking;
  22   o  put back the obsolete byte-codes for error-detection;
  23   o  added a new instruction, unbind_all, which I will use for
  24      tail-recursion elimination;
  25   o  made temp_output_buffer_show be called with the right number
  26      of args;
  27   o  made the new bytecodes be called with args in the right order;
  28   o  added metering support.
  29
  30 by Hallvard:
  31   o  added relative jump instructions;
  32   o  all conditionals now only do QUIT if they jump.
  33  */
  34
  35 #include <config.h>
  36 #include "lisp.h"
  37 #include "buffer.h"
  38 #include "syntax.h"
  39
  40 /*
  41  * define BYTE_CODE_SAFE to enable some minor sanity checking (useful for
  42  * debugging the byte compiler...)
  43  *
  44  * define BYTE_CODE_METER to enable generation of a byte-op usage histogram.
  45  */
  46 /* #define BYTE_CODE_SAFE */
  47 /* #define BYTE_CODE_METER */
  48
  49 \f
  50 #ifdef BYTE_CODE_METER
  51
  52 Lisp_Object Vbyte_code_meter, Qbyte_code_meter;
  53 int byte_metering_on;
  54
  55 #define METER_2(code1, code2) \
  56   XFASTINT (XVECTOR (XVECTOR (Vbyte_code_meter)->contents[(code1)]) \
  57             ->contents[(code2)])
  58
  59 #define METER_1(code) METER_2 (0, (code))
  60
  61 #define METER_CODE(last_code, this_code)                        \
  62 {                                                               \
  63   if (byte_metering_on)                                         \
  64     {                                                           \
  65       if (METER_1 (this_code) != ((1<<VALBITS)-1))              \
  66         METER_1 (this_code)++;                                  \
  67       if (last_code                                             \
  68           && METER_2 (last_code, this_code) != ((1<<VALBITS)-1))\
  69         METER_2 (last_code, this_code)++;                       \
  70     }                                                           \
  71 }
  72
  73 #else /* no BYTE_CODE_METER */
  74
  75 #define METER_CODE(last_code, this_code)
  76
  77 #endif /* no BYTE_CODE_METER */
  78 \f
  79
  80 Lisp_Object Qbytecode;
  81
  82 /*  Byte codes: */
  83
  84 #define Bvarref 010
  85 #define Bvarset 020
  86 #define Bvarbind 030
  87 #define Bcall 040
  88 #define Bunbind 050
  89
  90 #define Bnth 070
  91 #define Bsymbolp 071
  92 #define Bconsp 072
  93 #define Bstringp 073
  94 #define Blistp 074
  95 #define Beq 075
  96 #define Bmemq 076
  97 #define Bnot 077
  98 #define Bcar 0100
  99 #define Bcdr 0101
 100 #define Bcons 0102
 101 #define Blist1 0103
 102 #define Blist2 0104
 103 #define Blist3 0105
 104 #define Blist4 0106
 105 #define Blength 0107
 106 #define Baref 0110
 107 #define Baset 0111
 108 #define Bsymbol_value 0112
 109 #define Bsymbol_function 0113
 110 #define Bset 0114
 111 #define Bfset 0115
 112 #define Bget 0116
 113 #define Bsubstring 0117
 114 #define Bconcat2 0120
 115 #define Bconcat3 0121
 116 #define Bconcat4 0122
 117 #define Bsub1 0123
 118 #define Badd1 0124
 119 #define Beqlsign 0125
 120 #define Bgtr 0126
 121 #define Blss 0127
 122 #define Bleq 0130
 123 #define Bgeq 0131
 124 #define Bdiff 0132
 125 #define Bnegate 0133
 126 #define Bplus 0134
 127 #define Bmax 0135
 128 #define Bmin 0136
 129 #define Bmult 0137
 130
 131 #define Bpoint 0140
 132 #define Bmark 0141 /* no longer generated as of v18 */
 133 #define Bgoto_char 0142
 134 #define Binsert 0143
 135 #define Bpoint_max 0144
 136 #define Bpoint_min 0145
 137 #define Bchar_after 0146
 138 #define Bfollowing_char 0147
 139 #define Bpreceding_char 0150
 140 #define Bcurrent_column 0151
 141 #define Bindent_to 0152
 142 #define Bscan_buffer 0153 /* No longer generated as of v18 */
 143 #define Beolp 0154
 144 #define Beobp 0155
 145 #define Bbolp 0156
 146 #define Bbobp 0157
 147 #define Bcurrent_buffer 0160
 148 #define Bset_buffer 0161
 149 #define Bread_char 0162 /* No longer generated as of v19 */
 150 #define Bset_mark 0163 /* this loser is no longer generated as of v18 */
 151 #define Binteractive_p 0164 /* Needed since interactive-p takes unevalled args */
 152
 153 #define Bforward_char 0165
 154 #define Bforward_word 0166
 155 #define Bskip_chars_forward 0167
 156 #define Bskip_chars_backward 0170
 157 #define Bforward_line 0171
 158 #define Bchar_syntax 0172
 159 #define Bbuffer_substring 0173
 160 #define Bdelete_region 0174
 161 #define Bnarrow_to_region 0175
 162 #define Bwiden 0176
 163 #define Bend_of_line 0177
 164
 165 #define Bconstant2 0201
 166 #define Bgoto 0202
 167 #define Bgotoifnil 0203
 168 #define Bgotoifnonnil 0204
 169 #define Bgotoifnilelsepop 0205
 170 #define Bgotoifnonnilelsepop 0206
 171 #define Breturn 0207
 172 #define Bdiscard 0210
 173 #define Bdup 0211
 174
 175 #define Bsave_excursion 0212
 176 #define Bsave_window_excursion 0213
 177 #define Bsave_restriction 0214
 178 #define Bcatch 0215
 179
 180 #define Bunwind_protect 0216
 181 #define Bcondition_case 0217
 182 #define Btemp_output_buffer_setup 0220
 183 #define Btemp_output_buffer_show 0221
 184
 185 #define Bunbind_all 0222
 186
 187 #define Bset_marker 0223
 188 #define Bmatch_beginning 0224
 189 #define Bmatch_end 0225
 190 #define Bupcase 0226
 191 #define Bdowncase 0227
 192
 193 #define Bstringeqlsign 0230
 194 #define Bstringlss 0231
 195 #define Bequal 0232
 196 #define Bnthcdr 0233
 197 #define Belt 0234
 198 #define Bmember 0235
 199 #define Bassq 0236
 200 #define Bnreverse 0237
 201 #define Bsetcar 0240
 202 #define Bsetcdr 0241
 203 #define Bcar_safe 0242
 204 #define Bcdr_safe 0243
 205 #define Bnconc 0244
 206 #define Bquo 0245
 207 #define Brem 0246
 208 #define Bnumberp 0247
 209 #define Bintegerp 0250
 210
 211 #define BRgoto 0252
 212 #define BRgotoifnil 0253
 213 #define BRgotoifnonnil 0254
 214 #define BRgotoifnilelsepop 0255
 215 #define BRgotoifnonnilelsepop 0256
 216
 217 #define BlistN 0257
 218 #define BconcatN 0260
 219 #define BinsertN 0261
 220
 221 #define Bconstant 0300
 222 #define CONSTANTLIM 0100
 223 \f
 224 /* Fetch the next byte from the bytecode stream */
 225
 226 #define FETCH *pc++
 227
 228 /* Fetch two bytes from the bytecode stream
 229  and make a 16-bit number out of them */
 230
 231 #define FETCH2 (op = FETCH, op + (FETCH << 8))
 232
 233 /* Push x onto the execution stack. */
 234
 235 /* This used to be #define PUSH(x) (*++stackp = (x))
 236    This oddity is necessary because Alliant can't be bothered to
 237    compile the preincrement operator properly, as of 4/91.  -JimB  */
 238 #define PUSH(x) (stackp++, *stackp = (x))
 239
 240 /* Pop a value off the execution stack.  */
 241
 242 #define POP (*stackp--)
 243
 244 /* Discard n values from the execution stack.  */
 245
 246 #define DISCARD(n) (stackp -= (n))
 247
 248 /* Get the value which is at the top of the execution stack, but don't pop it. */
 249
 250 #define TOP (*stackp)
 251
 252 DEFUN ("byte-code", Fbyte_code, Sbyte_code, 3, 3, 0,
 253   "Function used internally in byte-compiled code.\n\
 254 The first argument is a string of byte code; the second, a vector of constants;\n\
 255 the third, the maximum stack depth used in this function.\n\
 256 If the third argument is incorrect, Emacs may crash.")
 257   (bytestr, vector, maxdepth)
 258      Lisp_Object bytestr, vector, maxdepth;
 259 {
 260   struct gcpro gcpro1, gcpro2, gcpro3;
 261   int count = specpdl_ptr - specpdl;
 262 #ifdef BYTE_CODE_METER
 263   int this_op = 0;
 264   int prev_op;
 265 #endif
 266   register int op;
 267   unsigned char *pc;
 268   Lisp_Object *stack;
 269   register Lisp_Object *stackp;
 270   Lisp_Object *stacke;
 271   register Lisp_Object v1, v2;
 272   register Lisp_Object *vectorp = XVECTOR (vector)->contents;
 273 #ifdef BYTE_CODE_SAFE
 274   register int const_length = XVECTOR (vector)->size;
 275 #endif
 276   /* Copy of BYTESTR, saved so we can tell if BYTESTR was relocated.  */
 277   Lisp_Object string_saved;
 278   /* Cached address of beginning of string,
 279      valid if BYTESTR equals STRING_SAVED.  */
 280   register unsigned char *strbeg;
 281
 282   CHECK_STRING (bytestr, 0);
 283   if (!VECTORP (vector))
 284     vector = wrong_type_argument (Qvectorp, vector);
 285   CHECK_NUMBER (maxdepth, 2);
 286
 287   stackp = (Lisp_Object *) alloca (XFASTINT (maxdepth) * sizeof (Lisp_Object));
 288   bzero (stackp, XFASTINT (maxdepth) * sizeof (Lisp_Object));
 289   GCPRO3 (bytestr, vector, *stackp);
 290   gcpro3.nvars = XFASTINT (maxdepth);
 291
 292   --stackp;
 293   stack = stackp;
 294   stacke = stackp + XFASTINT (maxdepth);
 295
 296   /* Initialize the saved pc-pointer for fetching from the string.  */
 297   string_saved = bytestr;
 298   pc = XSTRING (string_saved)->data;
 299
 300   while (1)
 301     {
 302 #ifdef BYTE_CODE_SAFE
 303       if (stackp > stacke)
 304         error ("Byte code stack overflow (byte compiler bug), pc %d, depth %d",
 305                pc - XSTRING (string_saved)->data, stacke - stackp);
 306       if (stackp < stack)
 307         error ("Byte code stack underflow (byte compiler bug), pc %d",
 308                pc - XSTRING (string_saved)->data);
 309 #endif
 310
 311       if (! EQ (string_saved, bytestr))
 312         {
 313           pc = pc - XSTRING (string_saved)->data + XSTRING (bytestr)->data;
 314           string_saved = bytestr;
 315         }
 316
 317 #ifdef BYTE_CODE_METER
 318       prev_op = this_op;
 319       this_op = op = FETCH;
 320       METER_CODE (prev_op, op);
 321       switch (op)
 322 #else
 323       switch (op = FETCH)
 324 #endif
 325         {
 326         case Bvarref+6:
 327           op = FETCH;
 328           goto varref;
 329
 330         case Bvarref+7:
 331           op = FETCH2;
 332           goto varref;
 333
 334         case Bvarref: case Bvarref+1: case Bvarref+2: case Bvarref+3:
 335         case Bvarref+4: case Bvarref+5:
 336           op = op - Bvarref;
 337         varref:
 338           v1 = vectorp[op];
 339           if (!SYMBOLP (v1))
 340             v2 = Fsymbol_value (v1);
 341           else
 342             {
 343               v2 = XSYMBOL (v1)->value;
 344 #ifdef SWITCH_ENUM_BUG
 345               switch ((int) XTYPE (v2))
 346 #else
 347               switch (XTYPE (v2))
 348 #endif
 349                 {
 350                 case Lisp_Symbol:
 351                   if (!EQ (v2, Qunbound))
 352                     break;
 353                 case Lisp_Misc:
 354                 case Lisp_Buffer_Local_Value:
 355                 case Lisp_Some_Buffer_Local_Value:
 356                   v2 = Fsymbol_value (v1);
 357                 }
 358             }
 359           PUSH (v2);
 360           break;
 361
 362         case Bvarset+6:
 363           op = FETCH;
 364           goto varset;
 365
 366         case Bvarset+7:
 367           op = FETCH2;
 368           goto varset;
 369
 370         case Bvarset: case Bvarset+1: case Bvarset+2: case Bvarset+3:
 371         case Bvarset+4: case Bvarset+5:
 372           op -= Bvarset;
 373         varset:
 374           Fset (vectorp[op], POP);
 375           break;
 376
 377         case Bvarbind+6:
 378           op = FETCH;
 379           goto varbind;
 380
 381         case Bvarbind+7:
 382           op = FETCH2;
 383           goto varbind;
 384
 385         case Bvarbind: case Bvarbind+1: case Bvarbind+2: case Bvarbind+3:
 386         case Bvarbind+4: case Bvarbind+5:
 387           op -= Bvarbind;
 388         varbind:
 389           specbind (vectorp[op], POP);
 390           break;
 391
 392         case Bcall+6:
 393           op = FETCH;
 394           goto docall;
 395
 396         case Bcall+7:
 397           op = FETCH2;
 398           goto docall;
 399
 400         case Bcall: case Bcall+1: case Bcall+2: case Bcall+3:
 401         case Bcall+4: case Bcall+5:
 402           op -= Bcall;
 403         docall:
 404           DISCARD (op);
 405 #ifdef BYTE_CODE_METER
 406           if (byte_metering_on && SYMBOLP (TOP))
 407             {
 408               v1 = TOP;
 409               v2 = Fget (v1, Qbyte_code_meter);
 410               if (INTEGERP (v2)
 411                   && XINT (v2) != ((1<<VALBITS)-1))
 412                 {
 413                   XSETINT (v2, XINT (v2) + 1);
 414                   Fput (v1, Qbyte_code_meter, v2);
 415                 }
 416             }
 417 #endif
 418           TOP = Ffuncall (op + 1, &TOP);
 419           break;
 420
 421         case Bunbind+6:
 422           op = FETCH;
 423           goto dounbind;
 424
 425         case Bunbind+7:
 426           op = FETCH2;
 427           goto dounbind;
 428
 429         case Bunbind: case Bunbind+1: case Bunbind+2: case Bunbind+3:
 430         case Bunbind+4: case Bunbind+5:
 431           op -= Bunbind;
 432         dounbind:
 433           unbind_to (specpdl_ptr - specpdl - op, Qnil);
 434           break;
 435
 436         case Bunbind_all:
 437           /* To unbind back to the beginning of this frame.  Not used yet,
 438              but will be needed for tail-recursion elimination.  */
 439           unbind_to (count, Qnil);
 440           break;
 441
 442         case Bgoto:
 443           QUIT;
 444           op = FETCH2;    /* pc = FETCH2 loses since FETCH2 contains pc++ */
 445           pc = XSTRING (string_saved)->data + op;
 446           break;
 447
 448         case Bgotoifnil:
 449           op = FETCH2;
 450           if (NILP (POP))
 451             {
 452               QUIT;
 453               pc = XSTRING (string_saved)->data + op;
 454             }
 455           break;
 456
 457         case Bgotoifnonnil:
 458           op = FETCH2;
 459           if (!NILP (POP))
 460             {
 461               QUIT;
 462               pc = XSTRING (string_saved)->data + op;
 463             }
 464           break;
 465
 466         case Bgotoifnilelsepop:
 467           op = FETCH2;
 468           if (NILP (TOP))
 469             {
 470               QUIT;
 471               pc = XSTRING (string_saved)->data + op;
 472             }
 473           else DISCARD (1);
 474           break;
 475
 476         case Bgotoifnonnilelsepop:
 477           op = FETCH2;
 478           if (!NILP (TOP))
 479             {
 480               QUIT;
 481               pc = XSTRING (string_saved)->data + op;
 482             }
 483           else DISCARD (1);
 484           break;
 485
 486         case BRgoto:
 487           QUIT;
 488           pc += *pc - 127;
 489           break;
 490
 491         case BRgotoifnil:
 492           if (NILP (POP))
 493             {
 494               QUIT;
 495               pc += *pc - 128;
 496             }
 497           pc++;
 498           break;
 499
 500         case BRgotoifnonnil:
 501           if (!NILP (POP))
 502             {
 503               QUIT;
 504               pc += *pc - 128;
 505             }
 506           pc++;
 507           break;
 508
 509         case BRgotoifnilelsepop:
 510           op = *pc++;
 511           if (NILP (TOP))
 512             {
 513               QUIT;
 514               pc += op - 128;
 515             }
 516           else DISCARD (1);
 517           break;
 518
 519         case BRgotoifnonnilelsepop:
 520           op = *pc++;
 521           if (!NILP (TOP))
 522             {
 523               QUIT;
 524               pc += op - 128;
 525             }
 526           else DISCARD (1);
 527           break;
 528
 529         case Breturn:
 530           v1 = POP;
 531           goto exit;
 532
 533         case Bdiscard:
 534           DISCARD (1);
 535           break;
 536
 537         case Bdup:
 538           v1 = TOP;
 539           PUSH (v1);
 540           break;
 541
 542         case Bconstant2:
 543           PUSH (vectorp[FETCH2]);
 544           break;
 545
 546         case Bsave_excursion:
 547           record_unwind_protect (save_excursion_restore, save_excursion_save ());
 548           break;
 549
 550         case Bsave_window_excursion:
 551           TOP = Fsave_window_excursion (TOP);
 552           break;
 553
 554         case Bsave_restriction:
 555           record_unwind_protect (save_restriction_restore, save_restriction_save ());
 556           break;
 557
 558         case Bcatch:
 559           v1 = POP;
 560           TOP = internal_catch (TOP, Feval, v1);
 561           break;
 562
 563         case Bunwind_protect:
 564           record_unwind_protect (0, POP);
 565           (specpdl_ptr - 1)->symbol = Qnil;
 566           break;
 567
 568         case Bcondition_case:
 569           v1 = POP;
 570           v1 = Fcons (POP, v1);
 571           TOP = Fcondition_case (Fcons (TOP, v1));
 572           break;
 573
 574         case Btemp_output_buffer_setup:
 575           temp_output_buffer_setup (XSTRING (TOP)->data);
 576           TOP = Vstandard_output;
 577           break;
 578
 579         case Btemp_output_buffer_show:
 580           v1 = POP;
 581           temp_output_buffer_show (TOP);
 582           TOP = v1;
 583           /* pop binding of standard-output */
 584           unbind_to (specpdl_ptr - specpdl - 1, Qnil);
 585           break;
 586
 587         case Bnth:
 588           v1 = POP;
 589           v2 = TOP;
 590         nth_entry:
 591           CHECK_NUMBER (v2, 0);
 592           op = XINT (v2);
 593           immediate_quit = 1;
 594           while (--op >= 0)
 595             {
 596               if (CONSP (v1))
 597                 v1 = XCONS (v1)->cdr;
 598               else if (!NILP (v1))
 599                 {
 600                   immediate_quit = 0;
 601                   v1 = wrong_type_argument (Qlistp, v1);
 602                   immediate_quit = 1;
 603                   op++;
 604                 }
 605             }
 606           immediate_quit = 0;
 607           goto docar;
 608
 609         case Bsymbolp:
 610           TOP = SYMBOLP (TOP) ? Qt : Qnil;
 611           break;
 612
 613         case Bconsp:
 614           TOP = CONSP (TOP) ? Qt : Qnil;
 615           break;
 616
 617         case Bstringp:
 618           TOP = STRINGP (TOP) ? Qt : Qnil;
 619           break;
 620
 621         case Blistp:
 622           TOP = CONSP (TOP) || NILP (TOP) ? Qt : Qnil;
 623           break;
 624
 625         case Beq:
 626           v1 = POP;
 627           TOP = EQ (v1, TOP) ? Qt : Qnil;
 628           break;
 629
 630         case Bmemq:
 631           v1 = POP;
 632           TOP = Fmemq (TOP, v1);
 633           break;
 634
 635         case Bnot:
 636           TOP = NILP (TOP) ? Qt : Qnil;
 637           break;
 638
 639         case Bcar:
 640           v1 = TOP;
 641         docar:
 642           if (CONSP (v1)) TOP = XCONS (v1)->car;
 643           else if (NILP (v1)) TOP = Qnil;
 644           else Fcar (wrong_type_argument (Qlistp, v1));
 645           break;
 646
 647         case Bcdr:
 648           v1 = TOP;
 649           if (CONSP (v1)) TOP = XCONS (v1)->cdr;
 650           else if (NILP (v1)) TOP = Qnil;
 651           else Fcdr (wrong_type_argument (Qlistp, v1));
 652           break;
 653
 654         case Bcons:
 655           v1 = POP;
 656           TOP = Fcons (TOP, v1);
 657           break;
 658
 659         case Blist1:
 660           TOP = Fcons (TOP, Qnil);
 661           break;
 662
 663         case Blist2:
 664           v1 = POP;
 665           TOP = Fcons (TOP, Fcons (v1, Qnil));
 666           break;
 667
 668         case Blist3:
 669           DISCARD (2);
 670           TOP = Flist (3, &TOP);
 671           break;
 672
 673         case Blist4:
 674           DISCARD (3);
 675           TOP = Flist (4, &TOP);
 676           break;
 677
 678         case BlistN:
 679           op = FETCH;
 680           DISCARD (op - 1);
 681           TOP = Flist (op, &TOP);
 682           break;
 683
 684         case Blength:
 685           TOP = Flength (TOP);
 686           break;
 687
 688         case Baref:
 689           v1 = POP;
 690           TOP = Faref (TOP, v1);
 691           break;
 692
 693         case Baset:
 694           v2 = POP; v1 = POP;
 695           TOP = Faset (TOP, v1, v2);
 696           break;
 697
 698         case Bsymbol_value:
 699           TOP = Fsymbol_value (TOP);
 700           break;
 701
 702         case Bsymbol_function:
 703           TOP = Fsymbol_function (TOP);
 704           break;
 705
 706         case Bset:
 707           v1 = POP;
 708           TOP = Fset (TOP, v1);
 709           break;
 710
 711         case Bfset:
 712           v1 = POP;
 713           TOP = Ffset (TOP, v1);
 714           break;
 715
 716         case Bget:
 717           v1 = POP;
 718           TOP = Fget (TOP, v1);
 719           break;
 720
 721         case Bsubstring:
 722           v2 = POP; v1 = POP;
 723           TOP = Fsubstring (TOP, v1, v2);
 724           break;
 725
 726         case Bconcat2:
 727           DISCARD (1);
 728           TOP = Fconcat (2, &TOP);
 729           break;
 730
 731         case Bconcat3:
 732           DISCARD (2);
 733           TOP = Fconcat (3, &TOP);
 734           break;
 735
 736         case Bconcat4:
 737           DISCARD (3);
 738           TOP = Fconcat (4, &TOP);
 739           break;
 740
 741         case BconcatN:
 742           op = FETCH;
 743           DISCARD (op - 1);
 744           TOP = Fconcat (op, &TOP);
 745           break;
 746
 747         case Bsub1:
 748           v1 = TOP;
 749           if (INTEGERP (v1))
 750             {
 751               XSETINT (v1, XINT (v1) - 1);
 752               TOP = v1;
 753             }
 754           else
 755             TOP = Fsub1 (v1);
 756           break;
 757
 758         case Badd1:
 759           v1 = TOP;
 760           if (INTEGERP (v1))
 761             {
 762               XSETINT (v1, XINT (v1) + 1);
 763               TOP = v1;
 764             }
 765           else
 766             TOP = Fadd1 (v1);
 767           break;
 768
 769         case Beqlsign:
 770           v2 = POP; v1 = TOP;
 771           CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v1, 0);
 772           CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v2, 0);
 773           TOP = (XFLOATINT (v1) == XFLOATINT (v2)) ? Qt : Qnil;
 774           break;
 775
 776         case Bgtr:
 777           v1 = POP;
 778           TOP = Fgtr (TOP, v1);
 779           break;
 780
 781         case Blss:
 782           v1 = POP;
 783           TOP = Flss (TOP, v1);
 784           break;
 785
 786         case Bleq:
 787           v1 = POP;
 788           TOP = Fleq (TOP, v1);
 789           break;
 790
 791         case Bgeq:
 792           v1 = POP;
 793           TOP = Fgeq (TOP, v1);
 794           break;
 795
 796         case Bdiff:
 797           DISCARD (1);
 798           TOP = Fminus (2, &TOP);
 799           break;
 800
 801         case Bnegate:
 802           v1 = TOP;
 803           if (INTEGERP (v1))
 804             {
 805               XSETINT (v1, - XINT (v1));
 806               TOP = v1;
 807             }
 808           else
 809             TOP = Fminus (1, &TOP);
 810           break;
 811
 812         case Bplus:
 813           DISCARD (1);
 814           TOP = Fplus (2, &TOP);
 815           break;
 816
 817         case Bmax:
 818           DISCARD (1);
 819           TOP = Fmax (2, &TOP);
 820           break;
 821
 822         case Bmin:
 823           DISCARD (1);
 824           TOP = Fmin (2, &TOP);
 825           break;
 826
 827         case Bmult:
 828           DISCARD (1);
 829           TOP = Ftimes (2, &TOP);
 830           break;
 831
 832         case Bquo:
 833           DISCARD (1);
 834           TOP = Fquo (2, &TOP);
 835           break;
 836
 837         case Brem:
 838           v1 = POP;
 839           TOP = Frem (TOP, v1);
 840           break;
 841
 842         case Bpoint:
 843           XSETFASTINT (v1, point);
 844           PUSH (v1);
 845           break;
 846
 847         case Bgoto_char:
 848           TOP = Fgoto_char (TOP);
 849           break;
 850
 851         case Binsert:
 852           TOP = Finsert (1, &TOP);
 853           break;
 854
 855         case BinsertN:
 856           op = FETCH;
 857           DISCARD (op - 1);
 858           TOP = Finsert (op, &TOP);
 859           break;
 860
 861         case Bpoint_max:
 862           XSETFASTINT (v1, ZV);
 863           PUSH (v1);
 864           break;
 865
 866         case Bpoint_min:
 867           XSETFASTINT (v1, BEGV);
 868           PUSH (v1);
 869           break;
 870
 871         case Bchar_after:
 872           TOP = Fchar_after (TOP);
 873           break;
 874
 875         case Bfollowing_char:
 876           XSETFASTINT (v1, PT == ZV ? 0 : FETCH_CHAR (point));
 877           PUSH (v1);
 878           break;
 879
 880         case Bpreceding_char:
 881           XSETFASTINT (v1, point <= BEGV ? 0 : FETCH_CHAR (point - 1));
 882           PUSH (v1);
 883           break;
 884
 885         case Bcurrent_column:
 886           XSETFASTINT (v1, current_column ());
 887           PUSH (v1);
 888           break;
 889
 890         case Bindent_to:
 891           TOP = Findent_to (TOP, Qnil);
 892           break;
 893
 894         case Beolp:
 895           PUSH (Feolp ());
 896           break;
 897
 898         case Beobp:
 899           PUSH (Feobp ());
 900           break;
 901
 902         case Bbolp:
 903           PUSH (Fbolp ());
 904           break;
 905
 906         case Bbobp:
 907           PUSH (Fbobp ());
 908           break;
 909
 910         case Bcurrent_buffer:
 911           PUSH (Fcurrent_buffer ());
 912           break;
 913
 914         case Bset_buffer:
 915           TOP = Fset_buffer (TOP);
 916           break;
 917
 918         case Bread_char:
 919           PUSH (Fread_char ());
 920           QUIT;
 921           break;
 922
 923         case Binteractive_p:
 924           PUSH (Finteractive_p ());
 925           break;
 926
 927         case Bforward_char:
 928           TOP = Fforward_char (TOP);
 929           break;
 930
 931         case Bforward_word:
 932           TOP = Fforward_word (TOP);
 933           break;
 934
 935         case Bskip_chars_forward:
 936           v1 = POP;
 937           TOP = Fskip_chars_forward (TOP, v1);
 938           break;
 939
 940         case Bskip_chars_backward:
 941           v1 = POP;
 942           TOP = Fskip_chars_backward (TOP, v1);
 943           break;
 944
 945         case Bforward_line:
 946           TOP = Fforward_line (TOP);
 947           break;
 948
 949         case Bchar_syntax:
 950           CHECK_NUMBER (TOP, 0);
 951           XSETFASTINT (TOP,
 952                        syntax_code_spec[(int) SYNTAX (0xFF & XINT (TOP))]);
 953           break;
 954
 955         case Bbuffer_substring:
 956           v1 = POP;
 957           TOP = Fbuffer_substring (TOP, v1);
 958           break;
 959
 960         case Bdelete_region:
 961           v1 = POP;
 962           TOP = Fdelete_region (TOP, v1);
 963           break;
 964
 965         case Bnarrow_to_region:
 966           v1 = POP;
 967           TOP = Fnarrow_to_region (TOP, v1);
 968           break;
 969
 970         case Bwiden:
 971           PUSH (Fwiden ());
 972           break;
 973
 974         case Bend_of_line:
 975           TOP = Fend_of_line (TOP);
 976           break;
 977
 978         case Bset_marker:
 979           v1 = POP;
 980           v2 = POP;
 981           TOP = Fset_marker (TOP, v2, v1);
 982           break;
 983
 984         case Bmatch_beginning:
 985           TOP = Fmatch_beginning (TOP);
 986           break;
 987
 988         case Bmatch_end:
 989           TOP = Fmatch_end (TOP);
 990           break;
 991
 992         case Bupcase:
 993           TOP = Fupcase (TOP);
 994           break;
 995
 996         case Bdowncase:
 997           TOP = Fdowncase (TOP);
 998         break;
 999
1000         case Bstringeqlsign:
1001           v1 = POP;
1002           TOP = Fstring_equal (TOP, v1);
1003           break;
1004
1005         case Bstringlss:
1006           v1 = POP;
1007           TOP = Fstring_lessp (TOP, v1);
1008           break;
1009
1010         case Bequal:
1011           v1 = POP;
1012           TOP = Fequal (TOP, v1);
1013           break;
1014
1015         case Bnthcdr:
1016           v1 = POP;
1017           TOP = Fnthcdr (TOP, v1);
1018           break;
1019
1020         case Belt:
1021           if (CONSP (TOP))
1022             {
1023               /* Exchange args and then do nth.  */
1024               v2 = POP;
1025               v1 = TOP;
1026               goto nth_entry;
1027             }
1028           v1 = POP;
1029           TOP = Felt (TOP, v1);
1030           break;
1031
1032         case Bmember:
1033           v1 = POP;
1034           TOP = Fmember (TOP, v1);
1035           break;
1036
1037         case Bassq:
1038           v1 = POP;
1039           TOP = Fassq (TOP, v1);
1040           break;
1041
1042         case Bnreverse:
1043           TOP = Fnreverse (TOP);
1044           break;
1045
1046         case Bsetcar:
1047           v1 = POP;
1048           TOP = Fsetcar (TOP, v1);
1049           break;
1050
1051         case Bsetcdr:
1052           v1 = POP;
1053           TOP = Fsetcdr (TOP, v1);
1054           break;
1055
1056         case Bcar_safe:
1057           v1 = TOP;
1058           if (CONSP (v1))
1059             TOP = XCONS (v1)->car;
1060           else
1061             TOP = Qnil;
1062           break;
1063
1064         case Bcdr_safe:
1065           v1 = TOP;
1066           if (CONSP (v1))
1067             TOP = XCONS (v1)->cdr;
1068           else
1069             TOP = Qnil;
1070           break;
1071
1072         case Bnconc:
1073           DISCARD (1);
1074           TOP = Fnconc (2, &TOP);
1075           break;
1076
1077         case Bnumberp:
1078           TOP = (NUMBERP (TOP) ? Qt : Qnil);
1079           break;
1080
1081         case Bintegerp:
1082           TOP = INTEGERP (TOP) ? Qt : Qnil;
1083           break;
1084
1085 #ifdef BYTE_CODE_SAFE
1086         case Bset_mark:
1087           error ("set-mark is an obsolete bytecode");
1088           break;
1089         case Bscan_buffer:
1090           error ("scan-buffer is an obsolete bytecode");
1091           break;
1092         case Bmark:
1093           error ("mark is an obsolete bytecode");
1094           break;
1095 #endif
1096
1097         default:
1098 #ifdef BYTE_CODE_SAFE
1099           if (op < Bconstant)
1100             error ("unknown bytecode %d (byte compiler bug)", op);
1101           if ((op -= Bconstant) >= const_length)
1102             error ("no constant number %d (byte compiler bug)", op);
1103           PUSH (vectorp[op]);
1104 #else
1105           PUSH (vectorp[op - Bconstant]);
1106 #endif
1107         }
1108     }
1109
1110  exit:
1111   UNGCPRO;
1112   /* Binds and unbinds are supposed to be compiled balanced.  */
1113   if (specpdl_ptr - specpdl != count)
1114 #ifdef BYTE_CODE_SAFE
1115     error ("binding stack not balanced (serious byte compiler bug)");
1116 #else
1117     abort ();
1118 #endif
1119   return v1;
1120 }
1121
1122 syms_of_bytecode ()
1123 {
1124   Qbytecode = intern ("byte-code");
1125   staticpro (&Qbytecode);
1126
1127   defsubr (&Sbyte_code);
1128
1129 #ifdef BYTE_CODE_METER
1130
1131   DEFVAR_LISP ("byte-code-meter", &Vbyte_code_meter,
1132    "A vector of vectors which holds a histogram of byte-code usage.\n\
1133 (aref (aref byte-code-meter 0) CODE) indicates how many times the byte\n\
1134 opcode CODE has been executed.\n\
1135 (aref (aref byte-code-meter CODE1) CODE2), where CODE1 is not 0,\n\
1136 indicates how many times the byte opcodes CODE1 and CODE2 have been\n\
1137 executed in succession.");
1138   DEFVAR_BOOL ("byte-metering-on", &byte_metering_on,
1139    "If non-nil, keep profiling information on byte code usage.\n\
1140 The variable byte-code-meter indicates how often each byte opcode is used.\n\
1141 If a symbol has a property named `byte-code-meter' whose value is an\n\
1142 integer, it is incremented each time that symbol's function is called.");
1143
1144   byte_metering_on = 0;
1145   Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
1146   Qbyte_code_meter = intern ("byte-code-meter");
1147   staticpro (&Qbyte_code_meter);
1148   {
1149     int i = 256;
1150     while (i--)
1151       XVECTOR (Vbyte_code_meter)->contents[i] =
1152         Fmake_vector (make_number (256), make_number (0));
1153   }
1154 #endif
1155 }