src/bytecode.c

   1 /* Execution of byte code produced by bytecomp.el.
   2    Copyright (C) 1985, 1986, 1987, 1988 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 1, 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 /* no longer generated as of v19 */
 110 #define Bset 0114
 111 #define Bfset 0115 /* no longer generated as of v19 */
 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 (XTYPE (vector) != Lisp_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 (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 (XTYPE (v1) != Lisp_Symbol)
 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_Intfwd:
 354                 case Lisp_Boolfwd:
 355                 case Lisp_Objfwd:
 356                 case Lisp_Buffer_Local_Value:
 357                 case Lisp_Some_Buffer_Local_Value:
 358                 case Lisp_Buffer_Objfwd:
 359                 case Lisp_Void:
 360                   v2 = Fsymbol_value (v1);
 361                 }
 362             }
 363           PUSH (v2);
 364           break;
 365
 366         case Bvarset+6:
 367           op = FETCH;
 368           goto varset;
 369
 370         case Bvarset+7:
 371           op = FETCH2;
 372           goto varset;
 373
 374         case Bvarset: case Bvarset+1: case Bvarset+2: case Bvarset+3:
 375         case Bvarset+4: case Bvarset+5:
 376           op -= Bvarset;
 377         varset:
 378           Fset (vectorp[op], POP);
 379           break;
 380
 381         case Bvarbind+6:
 382           op = FETCH;
 383           goto varbind;
 384
 385         case Bvarbind+7:
 386           op = FETCH2;
 387           goto varbind;
 388
 389         case Bvarbind: case Bvarbind+1: case Bvarbind+2: case Bvarbind+3:
 390         case Bvarbind+4: case Bvarbind+5:
 391           op -= Bvarbind;
 392         varbind:
 393           specbind (vectorp[op], POP);
 394           break;
 395
 396         case Bcall+6:
 397           op = FETCH;
 398           goto docall;
 399
 400         case Bcall+7:
 401           op = FETCH2;
 402           goto docall;
 403
 404         case Bcall: case Bcall+1: case Bcall+2: case Bcall+3:
 405         case Bcall+4: case Bcall+5:
 406           op -= Bcall;
 407         docall:
 408           DISCARD (op);
 409 #ifdef BYTE_CODE_METER
 410           if (byte_metering_on && XTYPE (TOP) == Lisp_Symbol)
 411             {
 412               v1 = TOP;
 413               v2 = Fget (v1, Qbyte_code_meter);
 414               if (XTYPE (v2) == Lisp_Int)
 415                 {
 416                   XSETINT (v2, XINT (v2) + 1);
 417                   Fput (v1, Qbyte_code_meter, v2);
 418                 }
 419             }
 420 #endif
 421           /* The frobbing of gcpro3 was lost by jwz's changes in June 91
 422              and then reinserted by jwz in Nov 91.  */
 423           /* Remove protection from the args we are giving to Ffuncall.
 424              FFuncall will protect them, and double protection would
 425              cause disasters.  */
 426           gcpro3.nvars = &TOP - stack - 1;
 427           TOP = Ffuncall (op + 1, &TOP);
 428           gcpro3.nvars = XFASTINT (maxdepth);
 429           break;
 430
 431         case Bunbind+6:
 432           op = FETCH;
 433           goto dounbind;
 434
 435         case Bunbind+7:
 436           op = FETCH2;
 437           goto dounbind;
 438
 439         case Bunbind: case Bunbind+1: case Bunbind+2: case Bunbind+3:
 440         case Bunbind+4: case Bunbind+5:
 441           op -= Bunbind;
 442         dounbind:
 443           unbind_to (specpdl_ptr - specpdl - op, Qnil);
 444           break;
 445
 446         case Bunbind_all:
 447           /* To unbind back to the beginning of this frame.  Not used yet,
 448              but will be needed for tail-recursion elimination.  */
 449           unbind_to (count, Qnil);
 450           break;
 451
 452         case Bgoto:
 453           QUIT;
 454           op = FETCH2;    /* pc = FETCH2 loses since FETCH2 contains pc++ */
 455           pc = XSTRING (string_saved)->data + op;
 456           break;
 457
 458         case Bgotoifnil:
 459           op = FETCH2;
 460           if (NULL (POP))
 461             {
 462               QUIT;
 463               pc = XSTRING (string_saved)->data + op;
 464             }
 465           break;
 466
 467         case Bgotoifnonnil:
 468           op = FETCH2;
 469           if (!NULL (POP))
 470             {
 471               QUIT;
 472               pc = XSTRING (string_saved)->data + op;
 473             }
 474           break;
 475
 476         case Bgotoifnilelsepop:
 477           op = FETCH2;
 478           if (NULL (TOP))
 479             {
 480               QUIT;
 481               pc = XSTRING (string_saved)->data + op;
 482             }
 483           else DISCARD (1);
 484           break;
 485
 486         case Bgotoifnonnilelsepop:
 487           op = FETCH2;
 488           if (!NULL (TOP))
 489             {
 490               QUIT;
 491               pc = XSTRING (string_saved)->data + op;
 492             }
 493           else DISCARD (1);
 494           break;
 495
 496         case BRgoto:
 497           QUIT;
 498           pc += *pc - 127;
 499           break;
 500
 501         case BRgotoifnil:
 502           if (NULL (POP))
 503             {
 504               QUIT;
 505               pc += *pc - 128;
 506             }
 507           pc++;
 508           break;
 509
 510         case BRgotoifnonnil:
 511           if (!NULL (POP))
 512             {
 513               QUIT;
 514               pc += *pc - 128;
 515             }
 516           pc++;
 517           break;
 518
 519         case BRgotoifnilelsepop:
 520           op = *pc++;
 521           if (NULL (TOP))
 522             {
 523               QUIT;
 524               pc += op - 128;
 525             }
 526           else DISCARD (1);
 527           break;
 528
 529         case BRgotoifnonnilelsepop:
 530           op = *pc++;
 531           if (!NULL (TOP))
 532             {
 533               QUIT;
 534               pc += op - 128;
 535             }
 536           else DISCARD (1);
 537           break;
 538
 539         case Breturn:
 540           v1 = POP;
 541           goto exit;
 542
 543         case Bdiscard:
 544           DISCARD (1);
 545           break;
 546
 547         case Bdup:
 548           v1 = TOP;
 549           PUSH (v1);
 550           break;
 551
 552         case Bconstant2:
 553           PUSH (vectorp[FETCH2]);
 554           break;
 555
 556         case Bsave_excursion:
 557           record_unwind_protect (save_excursion_restore, save_excursion_save ());
 558           break;
 559
 560         case Bsave_window_excursion:
 561           TOP = Fsave_window_excursion (TOP);
 562           break;
 563
 564         case Bsave_restriction:
 565           record_unwind_protect (save_restriction_restore, save_restriction_save ());
 566           break;
 567
 568         case Bcatch:
 569           v1 = POP;
 570           TOP = internal_catch (TOP, Feval, v1);
 571           break;
 572
 573         case Bunwind_protect:
 574           record_unwind_protect (0, POP);
 575           (specpdl_ptr - 1)->symbol = Qnil;
 576           break;
 577
 578         case Bcondition_case:
 579           v1 = POP;
 580           v1 = Fcons (POP, v1);
 581           TOP = Fcondition_case (Fcons (TOP, v1));
 582           break;
 583
 584         case Btemp_output_buffer_setup:
 585           temp_output_buffer_setup (XSTRING (TOP)->data);
 586           TOP = Vstandard_output;
 587           break;
 588
 589         case Btemp_output_buffer_show:
 590           v1 = POP;
 591           temp_output_buffer_show (TOP, Qnil);
 592           TOP = v1;
 593           /* pop binding of standard-output */
 594           unbind_to (specpdl_ptr - specpdl - 1, Qnil);
 595           break;
 596
 597         case Bnth:
 598           v1 = POP;
 599           v2 = TOP;
 600         nth_entry:
 601           CHECK_NUMBER (v2, 0);
 602           op = XINT (v2);
 603           immediate_quit = 1;
 604           while (--op >= 0)
 605             {
 606               if (CONSP (v1))
 607                 v1 = XCONS (v1)->cdr;
 608               else if (!NULL (v1))
 609                 {
 610                   immediate_quit = 0;
 611                   v1 = wrong_type_argument (Qlistp, v1);
 612                   immediate_quit = 1;
 613                   op++;
 614                 }
 615             }
 616           immediate_quit = 0;
 617           goto docar;
 618
 619         case Bsymbolp:
 620           TOP = XTYPE (TOP) == Lisp_Symbol ? Qt : Qnil;
 621           break;
 622
 623         case Bconsp:
 624           TOP = CONSP (TOP) ? Qt : Qnil;
 625           break;
 626
 627         case Bstringp:
 628           TOP = XTYPE (TOP) == Lisp_String ? Qt : Qnil;
 629           break;
 630
 631         case Blistp:
 632           TOP = CONSP (TOP) || NULL (TOP) ? Qt : Qnil;
 633           break;
 634
 635         case Beq:
 636           v1 = POP;
 637           TOP = EQ (v1, TOP) ? Qt : Qnil;
 638           break;
 639
 640         case Bmemq:
 641           v1 = POP;
 642           TOP = Fmemq (TOP, v1);
 643           break;
 644
 645         case Bnot:
 646           TOP = NULL (TOP) ? Qt : Qnil;
 647           break;
 648
 649         case Bcar:
 650           v1 = TOP;
 651         docar:
 652           if (CONSP (v1)) TOP = XCONS (v1)->car;
 653           else if (NULL (v1)) TOP = Qnil;
 654           else Fcar (wrong_type_argument (Qlistp, v1));
 655           break;
 656
 657         case Bcdr:
 658           v1 = TOP;
 659           if (CONSP (v1)) TOP = XCONS (v1)->cdr;
 660           else if (NULL (v1)) TOP = Qnil;
 661           else Fcdr (wrong_type_argument (Qlistp, v1));
 662           break;
 663
 664         case Bcons:
 665           v1 = POP;
 666           TOP = Fcons (TOP, v1);
 667           break;
 668
 669         case Blist1:
 670           TOP = Fcons (TOP, Qnil);
 671           break;
 672
 673         case Blist2:
 674           v1 = POP;
 675           TOP = Fcons (TOP, Fcons (v1, Qnil));
 676           break;
 677
 678         case Blist3:
 679           DISCARD (2);
 680           TOP = Flist (3, &TOP);
 681           break;
 682
 683         case Blist4:
 684           DISCARD (3);
 685           TOP = Flist (4, &TOP);
 686           break;
 687
 688         case BlistN:
 689           op = FETCH;
 690           DISCARD (op - 1);
 691           TOP = Flist (op, &TOP);
 692           break;
 693
 694         case Blength:
 695           TOP = Flength (TOP);
 696           break;
 697
 698         case Baref:
 699           v1 = POP;
 700           TOP = Faref (TOP, v1);
 701           break;
 702
 703         case Baset:
 704           v2 = POP; v1 = POP;
 705           TOP = Faset (TOP, v1, v2);
 706           break;
 707
 708         case Bsymbol_value:
 709           TOP = Fsymbol_value (TOP);
 710           break;
 711
 712         case Bsymbol_function:
 713           TOP = Fsymbol_function (TOP);
 714           break;
 715
 716         case Bset:
 717           v1 = POP;
 718           TOP = Fset (TOP, v1);
 719           break;
 720
 721         case Bfset:
 722           v1 = POP;
 723           TOP = Ffset (TOP, v1);
 724           break;
 725
 726         case Bget:
 727           v1 = POP;
 728           TOP = Fget (TOP, v1);
 729           break;
 730
 731         case Bsubstring:
 732           v2 = POP; v1 = POP;
 733           TOP = Fsubstring (TOP, v1, v2);
 734           break;
 735
 736         case Bconcat2:
 737           DISCARD (1);
 738           TOP = Fconcat (2, &TOP);
 739           break;
 740
 741         case Bconcat3:
 742           DISCARD (2);
 743           TOP = Fconcat (3, &TOP);
 744           break;
 745
 746         case Bconcat4:
 747           DISCARD (3);
 748           TOP = Fconcat (4, &TOP);
 749           break;
 750
 751         case BconcatN:
 752           op = FETCH;
 753           DISCARD (op - 1);
 754           TOP = Fconcat (op, &TOP);
 755           break;
 756
 757         case Bsub1:
 758           v1 = TOP;
 759           if (XTYPE (v1) == Lisp_Int)
 760             {
 761               XSETINT (v1, XINT (v1) - 1);
 762               TOP = v1;
 763             }
 764           else
 765             TOP = Fsub1 (v1);
 766           break;
 767
 768         case Badd1:
 769           v1 = TOP;
 770           if (XTYPE (v1) == Lisp_Int)
 771             {
 772               XSETINT (v1, XINT (v1) + 1);
 773               TOP = v1;
 774             }
 775           else
 776             TOP = Fadd1 (v1);
 777           break;
 778
 779         case Beqlsign:
 780           v2 = POP; v1 = TOP;
 781           CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v1, 0);
 782           CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v2, 0);
 783           TOP = (XFLOATINT (v1) == XFLOATINT (v2)) ? Qt : Qnil;
 784           break;
 785
 786         case Bgtr:
 787           v1 = POP;
 788           TOP = Fgtr (TOP, v1);
 789           break;
 790
 791         case Blss:
 792           v1 = POP;
 793           TOP = Flss (TOP, v1);
 794           break;
 795
 796         case Bleq:
 797           v1 = POP;
 798           TOP = Fleq (TOP, v1);
 799           break;
 800
 801         case Bgeq:
 802           v1 = POP;
 803           TOP = Fgeq (TOP, v1);
 804           break;
 805
 806         case Bdiff:
 807           DISCARD (1);
 808           TOP = Fminus (2, &TOP);
 809           break;
 810
 811         case Bnegate:
 812           v1 = TOP;
 813           if (XTYPE (v1) == Lisp_Int)
 814             {
 815               XSETINT (v1, - XINT (v1));
 816               TOP = v1;
 817             }
 818           else
 819             TOP = Fminus (1, &TOP);
 820           break;
 821
 822         case Bplus:
 823           DISCARD (1);
 824           TOP = Fplus (2, &TOP);
 825           break;
 826
 827         case Bmax:
 828           DISCARD (1);
 829           TOP = Fmax (2, &TOP);
 830           break;
 831
 832         case Bmin:
 833           DISCARD (1);
 834           TOP = Fmin (2, &TOP);
 835           break;
 836
 837         case Bmult:
 838           DISCARD (1);
 839           TOP = Ftimes (2, &TOP);
 840           break;
 841
 842         case Bquo:
 843           DISCARD (1);
 844           TOP = Fquo (2, &TOP);
 845           break;
 846
 847         case Brem:
 848           v1 = POP;
 849           TOP = Frem (TOP, v1);
 850           break;
 851
 852         case Bpoint:
 853           XFASTINT (v1) = point;
 854           PUSH (v1);
 855           break;
 856
 857         case Bgoto_char:
 858           TOP = Fgoto_char (TOP);
 859           break;
 860
 861         case Binsert:
 862           TOP = Finsert (1, &TOP);
 863           break;
 864
 865         case BinsertN:
 866           op = FETCH;
 867           DISCARD (op - 1);
 868           TOP = Finsert (op, &TOP);
 869           break;
 870
 871         case Bpoint_max:
 872           XFASTINT (v1) = ZV;
 873           PUSH (v1);
 874           break;
 875
 876         case Bpoint_min:
 877           XFASTINT (v1) = BEGV;
 878           PUSH (v1);
 879           break;
 880
 881         case Bchar_after:
 882           TOP = Fchar_after (TOP);
 883           break;
 884
 885         case Bfollowing_char:
 886           XFASTINT (v1) = PT == ZV ? 0 : FETCH_CHAR (point);
 887           PUSH (v1);
 888           break;
 889
 890         case Bpreceding_char:
 891           XFASTINT (v1) = point <= BEGV ? 0 : FETCH_CHAR (point - 1);
 892           PUSH (v1);
 893           break;
 894
 895         case Bcurrent_column:
 896           XFASTINT (v1) = current_column ();
 897           PUSH (v1);
 898           break;
 899
 900         case Bindent_to:
 901           TOP = Findent_to (TOP, Qnil);
 902           break;
 903
 904         case Beolp:
 905           PUSH (Feolp ());
 906           break;
 907
 908         case Beobp:
 909           PUSH (Feobp ());
 910           break;
 911
 912         case Bbolp:
 913           PUSH (Fbolp ());
 914           break;
 915
 916         case Bbobp:
 917           PUSH (Fbobp ());
 918           break;
 919
 920         case Bcurrent_buffer:
 921           PUSH (Fcurrent_buffer ());
 922           break;
 923
 924         case Bset_buffer:
 925           TOP = Fset_buffer (TOP);
 926           break;
 927
 928         case Bread_char:
 929           PUSH (Fread_char ());
 930           QUIT;
 931           break;
 932
 933         case Binteractive_p:
 934           PUSH (Finteractive_p ());
 935           break;
 936
 937         case Bforward_char:
 938           TOP = Fforward_char (TOP);
 939           break;
 940
 941         case Bforward_word:
 942           TOP = Fforward_word (TOP);
 943           break;
 944
 945         case Bskip_chars_forward:
 946           v1 = POP;
 947           TOP = Fskip_chars_forward (TOP, v1);
 948           break;
 949
 950         case Bskip_chars_backward:
 951           v1 = POP;
 952           TOP = Fskip_chars_backward (TOP, v1);
 953           break;
 954
 955         case Bforward_line:
 956           TOP = Fforward_line (TOP);
 957           break;
 958
 959         case Bchar_syntax:
 960           CHECK_NUMBER (TOP, 0);
 961           XFASTINT (TOP) = syntax_code_spec[(int) SYNTAX (0xFF & XINT (TOP))];
 962           break;
 963
 964         case Bbuffer_substring:
 965           v1 = POP;
 966           TOP = Fbuffer_substring (TOP, v1);
 967           break;
 968
 969         case Bdelete_region:
 970           v1 = POP;
 971           TOP = Fdelete_region (TOP, v1);
 972           break;
 973
 974         case Bnarrow_to_region:
 975           v1 = POP;
 976           TOP = Fnarrow_to_region (TOP, v1);
 977           break;
 978
 979         case Bwiden:
 980           PUSH (Fwiden ());
 981           break;
 982
 983         case Bend_of_line:
 984           TOP = Fend_of_line (TOP);
 985           break;
 986
 987         case Bset_marker:
 988           v1 = POP;
 989           v2 = POP;
 990           TOP = Fset_marker (TOP, v2, v1);
 991           break;
 992
 993         case Bmatch_beginning:
 994           TOP = Fmatch_beginning (TOP);
 995           break;
 996
 997         case Bmatch_end:
 998           TOP = Fmatch_end (TOP);
 999           break;
1000
1001         case Bupcase:
1002           TOP = Fupcase (TOP);
1003           break;
1004
1005         case Bdowncase:
1006           TOP = Fdowncase (TOP);
1007         break;
1008
1009         case Bstringeqlsign:
1010           v1 = POP;
1011           TOP = Fstring_equal (TOP, v1);
1012           break;
1013
1014         case Bstringlss:
1015           v1 = POP;
1016           TOP = Fstring_lessp (TOP, v1);
1017           break;
1018
1019         case Bequal:
1020           v1 = POP;
1021           TOP = Fequal (TOP, v1);
1022           break;
1023
1024         case Bnthcdr:
1025           v1 = POP;
1026           TOP = Fnthcdr (TOP, v1);
1027           break;
1028
1029         case Belt:
1030           if (XTYPE (TOP) == Lisp_Cons)
1031             {
1032               /* Exchange args and then do nth.  */
1033               v2 = POP;
1034               v1 = TOP;
1035               goto nth_entry;
1036             }
1037           v1 = POP;
1038           TOP = Felt (TOP, v1);
1039           break;
1040
1041         case Bmember:
1042           v1 = POP;
1043           TOP = Fmember (TOP, v1);
1044           break;
1045
1046         case Bassq:
1047           v1 = POP;
1048           TOP = Fassq (TOP, v1);
1049           break;
1050
1051         case Bnreverse:
1052           TOP = Fnreverse (TOP);
1053           break;
1054
1055         case Bsetcar:
1056           v1 = POP;
1057           TOP = Fsetcar (TOP, v1);
1058           break;
1059
1060         case Bsetcdr:
1061           v1 = POP;
1062           TOP = Fsetcdr (TOP, v1);
1063           break;
1064
1065         case Bcar_safe:
1066           v1 = TOP;
1067           if (XTYPE (v1) == Lisp_Cons)
1068             TOP = XCONS (v1)->car;
1069           else
1070             TOP = Qnil;
1071           break;
1072
1073         case Bcdr_safe:
1074           v1 = TOP;
1075           if (XTYPE (v1) == Lisp_Cons)
1076             TOP = XCONS (v1)->cdr;
1077           else
1078             TOP = Qnil;
1079           break;
1080
1081         case Bnconc:
1082           DISCARD (1);
1083           TOP = Fnconc (2, &TOP);
1084           break;
1085
1086         case Bnumberp:
1087           TOP = (XTYPE (TOP) == Lisp_Int || XTYPE (TOP) == Lisp_Float
1088                  ? Qt : Qnil);
1089           break;
1090
1091         case Bintegerp:
1092           TOP = XTYPE (TOP) == Lisp_Int ? Qt : Qnil;
1093           break;
1094
1095 #ifdef BYTE_CODE_SAFE
1096         case Bset_mark:
1097           error ("set-mark is an obsolete bytecode");
1098           break;
1099         case Bscan_buffer:
1100           error ("scan-buffer is an obsolete bytecode");
1101           break;
1102         case Bmark:
1103           error ("mark is an obsolete bytecode");
1104           break;
1105 #endif
1106
1107         default:
1108 #ifdef BYTE_CODE_SAFE
1109           if (op < Bconstant)
1110             error ("unknown bytecode %d (byte compiler bug)", op);
1111           if ((op -= Bconstant) >= const_length)
1112             error ("no constant number %d (byte compiler bug)", op);
1113           PUSH (vectorp[op]);
1114 #else
1115           PUSH (vectorp[op - Bconstant]);
1116 #endif
1117         }
1118     }
1119
1120  exit:
1121   UNGCPRO;
1122   /* Binds and unbinds are supposed to be compiled balanced.  */
1123   if (specpdl_ptr - specpdl != count)
1124 #ifdef BYTE_CODE_SAFE
1125     error ("binding stack not balanced (serious byte compiler bug)");
1126 #else
1127     abort ();
1128 #endif
1129   return v1;
1130 }
1131
1132 syms_of_bytecode ()
1133 {
1134   Qbytecode = intern ("byte-code");
1135   staticpro (&Qbytecode);
1136
1137   defsubr (&Sbyte_code);
1138
1139 #ifdef BYTE_CODE_METER
1140
1141   DEFVAR_LISP ("byte-code-meter", &Vbyte_code_meter,
1142    "A vector of vectors which holds a histogram of byte-code usage.");
1143   DEFVAR_BOOL ("byte-metering-on", &byte_metering_on, "");
1144
1145   byte_metering_on = 0;
1146   Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
1147   Qbyte_code_meter = intern ("byte-code-meter");
1148   staticpro (&Qbyte_code_meter);
1149   {
1150     int i = 256;
1151     while (i--)
1152       XVECTOR (Vbyte_code_meter)->contents[i] =
1153         Fmake_vector (make_number (256), make_number (0));
1154   }
1155 #endif
1156 }