src/bytecode.c

   1 /* Execution of byte code produced by bytecomp.el.
   2    Copyright (C) 1985, 1986, 1987, 1988, 1993, 2000, 2001, 2002, 2003, 2004,
   3                  2005, 2006 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.
  21
  22 hacked on by jwz@lucid.com 17-jun-91
  23   o  added a compile-time switch to turn on simple sanity checking;
  24   o  put back the obsolete byte-codes for error-detection;
  25   o  added a new instruction, unbind_all, which I will use for
  26      tail-recursion elimination;
  27   o  made temp_output_buffer_show be called with the right number
  28      of args;
  29   o  made the new bytecodes be called with args in the right order;
  30   o  added metering support.
  31
  32 by Hallvard:
  33   o  added relative jump instructions;
  34   o  all conditionals now only do QUIT if they jump.
  35  */
  36
  37 #include <config.h>
  38 #include "lisp.h"
  39 #include "buffer.h"
  40 #include "charset.h"
  41 #include "syntax.h"
  42 #include "window.h"
  43
  44 #ifdef CHECK_FRAME_FONT
  45 #include "frame.h"
  46 #include "xterm.h"
  47 #endif
  48
  49 /*
  50  * define BYTE_CODE_SAFE to enable some minor sanity checking (useful for
  51  * debugging the byte compiler...)
  52  *
  53  * define BYTE_CODE_METER to enable generation of a byte-op usage histogram.
  54  */
  55 /* #define BYTE_CODE_SAFE */
  56 /* #define BYTE_CODE_METER */
  57
  58 \f
  59 #ifdef BYTE_CODE_METER
  60
  61 Lisp_Object Vbyte_code_meter, Qbyte_code_meter;
  62 int byte_metering_on;
  63
  64 #define METER_2(code1, code2) \
  65   XFASTINT (XVECTOR (XVECTOR (Vbyte_code_meter)->contents[(code1)]) \
  66             ->contents[(code2)])
  67
  68 #define METER_1(code) METER_2 (0, (code))
  69
  70 #define METER_CODE(last_code, this_code)                                \
  71 {                                                                       \
  72   if (byte_metering_on)                                                 \
  73     {                                                                   \
  74       if (METER_1 (this_code) < MOST_POSITIVE_FIXNUM)                   \
  75         METER_1 (this_code)++;                                          \
  76       if (last_code                                                     \
  77           && METER_2 (last_code, this_code) < MOST_POSITIVE_FIXNUM)     \
  78         METER_2 (last_code, this_code)++;                               \
  79     }                                                                   \
  80 }
  81
  82 #else /* no BYTE_CODE_METER */
  83
  84 #define METER_CODE(last_code, this_code)
  85
  86 #endif /* no BYTE_CODE_METER */
  87 \f
  88
  89 Lisp_Object Qbytecode;
  90
  91 /*  Byte codes: */
  92
  93 #define Bvarref 010
  94 #define Bvarset 020
  95 #define Bvarbind 030
  96 #define Bcall 040
  97 #define Bunbind 050
  98
  99 #define Bnth 070
 100 #define Bsymbolp 071
 101 #define Bconsp 072
 102 #define Bstringp 073
 103 #define Blistp 074
 104 #define Beq 075
 105 #define Bmemq 076
 106 #define Bnot 077
 107 #define Bcar 0100
 108 #define Bcdr 0101
 109 #define Bcons 0102
 110 #define Blist1 0103
 111 #define Blist2 0104
 112 #define Blist3 0105
 113 #define Blist4 0106
 114 #define Blength 0107
 115 #define Baref 0110
 116 #define Baset 0111
 117 #define Bsymbol_value 0112
 118 #define Bsymbol_function 0113
 119 #define Bset 0114
 120 #define Bfset 0115
 121 #define Bget 0116
 122 #define Bsubstring 0117
 123 #define Bconcat2 0120
 124 #define Bconcat3 0121
 125 #define Bconcat4 0122
 126 #define Bsub1 0123
 127 #define Badd1 0124
 128 #define Beqlsign 0125
 129 #define Bgtr 0126
 130 #define Blss 0127
 131 #define Bleq 0130
 132 #define Bgeq 0131
 133 #define Bdiff 0132
 134 #define Bnegate 0133
 135 #define Bplus 0134
 136 #define Bmax 0135
 137 #define Bmin 0136
 138 #define Bmult 0137
 139
 140 #define Bpoint 0140
 141 /* Was Bmark in v17.  */
 142 #define Bsave_current_buffer 0141
 143 #define Bgoto_char 0142
 144 #define Binsert 0143
 145 #define Bpoint_max 0144
 146 #define Bpoint_min 0145
 147 #define Bchar_after 0146
 148 #define Bfollowing_char 0147
 149 #define Bpreceding_char 0150
 150 #define Bcurrent_column 0151
 151 #define Bindent_to 0152
 152 #define Bscan_buffer 0153 /* No longer generated as of v18 */
 153 #define Beolp 0154
 154 #define Beobp 0155
 155 #define Bbolp 0156
 156 #define Bbobp 0157
 157 #define Bcurrent_buffer 0160
 158 #define Bset_buffer 0161
 159 #define Bsave_current_buffer_1 0162 /* Replacing Bsave_current_buffer.  */
 160 #define Bread_char 0162 /* No longer generated as of v19 */
 161 #define Bset_mark 0163 /* this loser is no longer generated as of v18 */
 162 #define Binteractive_p 0164 /* Needed since interactive-p takes unevalled args */
 163
 164 #define Bforward_char 0165
 165 #define Bforward_word 0166
 166 #define Bskip_chars_forward 0167
 167 #define Bskip_chars_backward 0170
 168 #define Bforward_line 0171
 169 #define Bchar_syntax 0172
 170 #define Bbuffer_substring 0173
 171 #define Bdelete_region 0174
 172 #define Bnarrow_to_region 0175
 173 #define Bwiden 0176
 174 #define Bend_of_line 0177
 175
 176 #define Bconstant2 0201
 177 #define Bgoto 0202
 178 #define Bgotoifnil 0203
 179 #define Bgotoifnonnil 0204
 180 #define Bgotoifnilelsepop 0205
 181 #define Bgotoifnonnilelsepop 0206
 182 #define Breturn 0207
 183 #define Bdiscard 0210
 184 #define Bdup 0211
 185
 186 #define Bsave_excursion 0212
 187 #define Bsave_window_excursion 0213
 188 #define Bsave_restriction 0214
 189 #define Bcatch 0215
 190
 191 #define Bunwind_protect 0216
 192 #define Bcondition_case 0217
 193 #define Btemp_output_buffer_setup 0220
 194 #define Btemp_output_buffer_show 0221
 195
 196 #define Bunbind_all 0222
 197
 198 #define Bset_marker 0223
 199 #define Bmatch_beginning 0224
 200 #define Bmatch_end 0225
 201 #define Bupcase 0226
 202 #define Bdowncase 0227
 203
 204 #define Bstringeqlsign 0230
 205 #define Bstringlss 0231
 206 #define Bequal 0232
 207 #define Bnthcdr 0233
 208 #define Belt 0234
 209 #define Bmember 0235
 210 #define Bassq 0236
 211 #define Bnreverse 0237
 212 #define Bsetcar 0240
 213 #define Bsetcdr 0241
 214 #define Bcar_safe 0242
 215 #define Bcdr_safe 0243
 216 #define Bnconc 0244
 217 #define Bquo 0245
 218 #define Brem 0246
 219 #define Bnumberp 0247
 220 #define Bintegerp 0250
 221
 222 #define BRgoto 0252
 223 #define BRgotoifnil 0253
 224 #define BRgotoifnonnil 0254
 225 #define BRgotoifnilelsepop 0255
 226 #define BRgotoifnonnilelsepop 0256
 227
 228 #define BlistN 0257
 229 #define BconcatN 0260
 230 #define BinsertN 0261
 231
 232 #define Bconstant 0300
 233 #define CONSTANTLIM 0100
 234
 235 \f
 236 /* Structure describing a value stack used during byte-code execution
 237    in Fbyte_code.  */
 238
 239 struct byte_stack
 240 {
 241   /* Program counter.  This points into the byte_string below
 242      and is relocated when that string is relocated.  */
 243   const unsigned char *pc;
 244
 245   /* Top and bottom of stack.  The bottom points to an area of memory
 246      allocated with alloca in Fbyte_code.  */
 247   Lisp_Object *top, *bottom;
 248
 249   /* The string containing the byte-code, and its current address.
 250      Storing this here protects it from GC because mark_byte_stack
 251      marks it.  */
 252   Lisp_Object byte_string;
 253   const unsigned char *byte_string_start;
 254
 255   /* The vector of constants used during byte-code execution.  Storing
 256      this here protects it from GC because mark_byte_stack marks it.  */
 257   Lisp_Object constants;
 258
 259   /* Next entry in byte_stack_list.  */
 260   struct byte_stack *next;
 261 };
 262
 263 /* A list of currently active byte-code execution value stacks.
 264    Fbyte_code adds an entry to the head of this list before it starts
 265    processing byte-code, and it removed the entry again when it is
 266    done.  Signalling an error truncates the list analoguous to
 267    gcprolist.  */
 268
 269 struct byte_stack *byte_stack_list;
 270
 271 \f
 272 /* Mark objects on byte_stack_list.  Called during GC.  */
 273
 274 void
 275 mark_byte_stack ()
 276 {
 277   struct byte_stack *stack;
 278   Lisp_Object *obj;
 279
 280   for (stack = byte_stack_list; stack; stack = stack->next)
 281     {
 282       /* If STACK->top is null here, this means there's an opcode in
 283          Fbyte_code that wasn't expected to GC, but did.  To find out
 284          which opcode this is, record the value of `stack', and walk
 285          up the stack in a debugger, stopping in frames of Fbyte_code.
 286          The culprit is found in the frame of Fbyte_code where the
 287          address of its local variable `stack' is equal to the
 288          recorded value of `stack' here.  */
 289       eassert (stack->top);
 290
 291       for (obj = stack->bottom; obj <= stack->top; ++obj)
 292         mark_object (*obj);
 293
 294       mark_object (stack->byte_string);
 295       mark_object (stack->constants);
 296     }
 297 }
 298
 299
 300 /* Unmark objects in the stacks on byte_stack_list.  Relocate program
 301    counters.  Called when GC has completed.  */
 302
 303 void
 304 unmark_byte_stack ()
 305 {
 306   struct byte_stack *stack;
 307
 308   for (stack = byte_stack_list; stack; stack = stack->next)
 309     {
 310       if (stack->byte_string_start != SDATA (stack->byte_string))
 311         {
 312           int offset = stack->pc - stack->byte_string_start;
 313           stack->byte_string_start = SDATA (stack->byte_string);
 314           stack->pc = stack->byte_string_start + offset;
 315         }
 316     }
 317 }
 318
 319 \f
 320 /* Fetch the next byte from the bytecode stream */
 321
 322 #define FETCH *stack.pc++
 323
 324 /* Fetch two bytes from the bytecode stream and make a 16-bit number
 325    out of them */
 326
 327 #define FETCH2 (op = FETCH, op + (FETCH << 8))
 328
 329 /* Push x onto the execution stack.  This used to be #define PUSH(x)
 330    (*++stackp = (x)) This oddity is necessary because Alliant can't be
 331    bothered to compile the preincrement operator properly, as of 4/91.
 332    -JimB */
 333
 334 #define PUSH(x) (top++, *top = (x))
 335
 336 /* Pop a value off the execution stack.  */
 337
 338 #define POP (*top--)
 339
 340 /* Discard n values from the execution stack.  */
 341
 342 #define DISCARD(n) (top -= (n))
 343
 344 /* Get the value which is at the top of the execution stack, but don't
 345    pop it. */
 346
 347 #define TOP (*top)
 348
 349 /* Actions that must be performed before and after calling a function
 350    that might GC.  */
 351
 352 #define BEFORE_POTENTIAL_GC()   stack.top = top
 353 #define AFTER_POTENTIAL_GC()    stack.top = NULL
 354
 355 /* Garbage collect if we have consed enough since the last time.
 356    We do this at every branch, to avoid loops that never GC.  */
 357
 358 #define MAYBE_GC()                                      \
 359   if (consing_since_gc > gc_cons_threshold              \
 360       && consing_since_gc > gc_relative_threshold)      \
 361     {                                                   \
 362       BEFORE_POTENTIAL_GC ();                           \
 363       Fgarbage_collect ();                              \
 364       AFTER_POTENTIAL_GC ();                            \
 365     }                                                   \
 366   else
 367
 368 /* Check for jumping out of range.  */
 369
 370 #ifdef BYTE_CODE_SAFE
 371
 372 #define CHECK_RANGE(ARG) \
 373   if (ARG >= bytestr_length) abort ()
 374
 375 #else /* not BYTE_CODE_SAFE */
 376
 377 #define CHECK_RANGE(ARG)
 378
 379 #endif /* not BYTE_CODE_SAFE */
 380
 381 /* A version of the QUIT macro which makes sure that the stack top is
 382    set before signaling `quit'.  */
 383
 384 #define BYTE_CODE_QUIT                                  \
 385   do {                                                  \
 386     if (!NILP (Vquit_flag) && NILP (Vinhibit_quit))     \
 387       {                                                 \
 388         Lisp_Object flag = Vquit_flag;                  \
 389         Vquit_flag = Qnil;                              \
 390         BEFORE_POTENTIAL_GC ();                         \
 391         if (EQ (Vthrow_on_input, flag))                 \
 392           Fthrow (Vthrow_on_input, Qt);                 \
 393         Fsignal (Qquit, Qnil);                          \
 394         AFTER_POTENTIAL_GC ();                          \
 395       }                                                 \
 396   } while (0)
 397
 398
 399 DEFUN ("byte-code", Fbyte_code, Sbyte_code, 3, 3, 0,
 400        doc: /* Function used internally in byte-compiled code.
 401 The first argument, BYTESTR, is a string of byte code;
 402 the second, VECTOR, a vector of constants;
 403 the third, MAXDEPTH, the maximum stack depth used in this function.
 404 If the third argument is incorrect, Emacs may crash.  */)
 405      (bytestr, vector, maxdepth)
 406      Lisp_Object bytestr, vector, maxdepth;
 407 {
 408   int count = SPECPDL_INDEX ();
 409 #ifdef BYTE_CODE_METER
 410   int this_op = 0;
 411   int prev_op;
 412 #endif
 413   int op;
 414   /* Lisp_Object v1, v2; */
 415   Lisp_Object *vectorp;
 416 #ifdef BYTE_CODE_SAFE
 417   int const_length = XVECTOR (vector)->size;
 418   Lisp_Object *stacke;
 419 #endif
 420   int bytestr_length;
 421   struct byte_stack stack;
 422   Lisp_Object *top;
 423   Lisp_Object result;
 424
 425 #ifdef CHECK_FRAME_FONT
 426  {
 427    struct frame *f = SELECTED_FRAME ();
 428    if (FRAME_X_P (f)
 429        && FRAME_FONT (f)->direction != 0
 430        && FRAME_FONT (f)->direction != 1)
 431      abort ();
 432  }
 433 #endif
 434
 435   CHECK_STRING (bytestr);
 436   CHECK_VECTOR (vector);
 437   CHECK_NUMBER (maxdepth);
 438
 439   if (STRING_MULTIBYTE (bytestr))
 440     /* BYTESTR must have been produced by Emacs 20.2 or the earlier
 441        because they produced a raw 8-bit string for byte-code and now
 442        such a byte-code string is loaded as multibyte while raw 8-bit
 443        characters converted to multibyte form.  Thus, now we must
 444        convert them back to the originally intended unibyte form.  */
 445     bytestr = Fstring_as_unibyte (bytestr);
 446
 447   bytestr_length = SBYTES (bytestr);
 448   vectorp = XVECTOR (vector)->contents;
 449
 450   stack.byte_string = bytestr;
 451   stack.pc = stack.byte_string_start = SDATA (bytestr);
 452   stack.constants = vector;
 453   stack.bottom = (Lisp_Object *) alloca (XFASTINT (maxdepth)
 454                                          * sizeof (Lisp_Object));
 455   top = stack.bottom - 1;
 456   stack.top = NULL;
 457   stack.next = byte_stack_list;
 458   byte_stack_list = &stack;
 459
 460 #ifdef BYTE_CODE_SAFE
 461   stacke = stack.bottom - 1 + XFASTINT (maxdepth);
 462 #endif
 463
 464   while (1)
 465     {
 466 #ifdef BYTE_CODE_SAFE
 467       if (top > stacke)
 468         abort ();
 469       else if (top < stack.bottom - 1)
 470         abort ();
 471 #endif
 472
 473 #ifdef BYTE_CODE_METER
 474       prev_op = this_op;
 475       this_op = op = FETCH;
 476       METER_CODE (prev_op, op);
 477 #else
 478       op = FETCH;
 479 #endif
 480
 481       switch (op)
 482         {
 483         case Bvarref + 7:
 484           op = FETCH2;
 485           goto varref;
 486
 487         case Bvarref:
 488         case Bvarref + 1:
 489         case Bvarref + 2:
 490         case Bvarref + 3:
 491         case Bvarref + 4:
 492         case Bvarref + 5:
 493           op = op - Bvarref;
 494           goto varref;
 495
 496         /* This seems to be the most frequently executed byte-code
 497            among the Bvarref's, so avoid a goto here.  */
 498         case Bvarref+6:
 499           op = FETCH;
 500         varref:
 501           {
 502             Lisp_Object v1, v2;
 503
 504             v1 = vectorp[op];
 505             if (SYMBOLP (v1))
 506               {
 507                 v2 = SYMBOL_VALUE (v1);
 508                 if (MISCP (v2) || EQ (v2, Qunbound))
 509                   {
 510                     BEFORE_POTENTIAL_GC ();
 511                     v2 = Fsymbol_value (v1);
 512                     AFTER_POTENTIAL_GC ();
 513                   }
 514               }
 515             else
 516               {
 517                 BEFORE_POTENTIAL_GC ();
 518                 v2 = Fsymbol_value (v1);
 519                 AFTER_POTENTIAL_GC ();
 520               }
 521             PUSH (v2);
 522             break;
 523           }
 524
 525         case Bgotoifnil:
 526           {
 527             Lisp_Object v1;
 528             MAYBE_GC ();
 529             op = FETCH2;
 530             v1 = POP;
 531             if (NILP (v1))
 532               {
 533                 BYTE_CODE_QUIT;
 534                 CHECK_RANGE (op);
 535                 stack.pc = stack.byte_string_start + op;
 536               }
 537             break;
 538           }
 539
 540         case Bcar:
 541           {
 542             Lisp_Object v1;
 543             v1 = TOP;
 544             TOP = CAR (v1);
 545             break;
 546           }
 547
 548         case Beq:
 549           {
 550             Lisp_Object v1;
 551             v1 = POP;
 552             TOP = EQ (v1, TOP) ? Qt : Qnil;
 553             break;
 554           }
 555
 556         case Bmemq:
 557           {
 558             Lisp_Object v1;
 559             BEFORE_POTENTIAL_GC ();
 560             v1 = POP;
 561             TOP = Fmemq (TOP, v1);
 562             AFTER_POTENTIAL_GC ();
 563             break;
 564           }
 565
 566         case Bcdr:
 567           {
 568             Lisp_Object v1;
 569             v1 = TOP;
 570             TOP = CDR (v1);
 571             break;
 572           }
 573
 574         case Bvarset:
 575         case Bvarset+1:
 576         case Bvarset+2:
 577         case Bvarset+3:
 578         case Bvarset+4:
 579         case Bvarset+5:
 580           op -= Bvarset;
 581           goto varset;
 582
 583         case Bvarset+7:
 584           op = FETCH2;
 585           goto varset;
 586
 587         case Bvarset+6:
 588           op = FETCH;
 589         varset:
 590           {
 591             Lisp_Object sym, val;
 592
 593             sym = vectorp[op];
 594             val = TOP;
 595
 596             /* Inline the most common case.  */
 597             if (SYMBOLP (sym)
 598                 && !EQ (val, Qunbound)
 599                 && !XSYMBOL (sym)->indirect_variable
 600                 && !SYMBOL_CONSTANT_P (sym)
 601                 && !MISCP (XSYMBOL (sym)->value))
 602               XSYMBOL (sym)->value = val;
 603             else
 604               {
 605                 BEFORE_POTENTIAL_GC ();
 606                 set_internal (sym, val, current_buffer, 0);
 607                 AFTER_POTENTIAL_GC ();
 608               }
 609           }
 610           (void) POP;
 611           break;
 612
 613         case Bdup:
 614           {
 615             Lisp_Object v1;
 616             v1 = TOP;
 617             PUSH (v1);
 618             break;
 619           }
 620
 621         /* ------------------ */
 622
 623         case Bvarbind+6:
 624           op = FETCH;
 625           goto varbind;
 626
 627         case Bvarbind+7:
 628           op = FETCH2;
 629           goto varbind;
 630
 631         case Bvarbind:
 632         case Bvarbind+1:
 633         case Bvarbind+2:
 634         case Bvarbind+3:
 635         case Bvarbind+4:
 636         case Bvarbind+5:
 637           op -= Bvarbind;
 638         varbind:
 639           /* Specbind can signal and thus GC.  */
 640           BEFORE_POTENTIAL_GC ();
 641           specbind (vectorp[op], POP);
 642           AFTER_POTENTIAL_GC ();
 643           break;
 644
 645         case Bcall+6:
 646           op = FETCH;
 647           goto docall;
 648
 649         case Bcall+7:
 650           op = FETCH2;
 651           goto docall;
 652
 653         case Bcall:
 654         case Bcall+1:
 655         case Bcall+2:
 656         case Bcall+3:
 657         case Bcall+4:
 658         case Bcall+5:
 659           op -= Bcall;
 660         docall:
 661           {
 662             BEFORE_POTENTIAL_GC ();
 663             DISCARD (op);
 664 #ifdef BYTE_CODE_METER
 665             if (byte_metering_on && SYMBOLP (TOP))
 666               {
 667                 Lisp_Object v1, v2;
 668
 669                 v1 = TOP;
 670                 v2 = Fget (v1, Qbyte_code_meter);
 671                 if (INTEGERP (v2)
 672                     && XINT (v2) < MOST_POSITIVE_FIXNUM)
 673                   {
 674                     XSETINT (v2, XINT (v2) + 1);
 675                     Fput (v1, Qbyte_code_meter, v2);
 676                   }
 677               }
 678 #endif
 679             TOP = Ffuncall (op + 1, &TOP);
 680             AFTER_POTENTIAL_GC ();
 681             break;
 682           }
 683
 684         case Bunbind+6:
 685           op = FETCH;
 686           goto dounbind;
 687
 688         case Bunbind+7:
 689           op = FETCH2;
 690           goto dounbind;
 691
 692         case Bunbind:
 693         case Bunbind+1:
 694         case Bunbind+2:
 695         case Bunbind+3:
 696         case Bunbind+4:
 697         case Bunbind+5:
 698           op -= Bunbind;
 699         dounbind:
 700           BEFORE_POTENTIAL_GC ();
 701           unbind_to (SPECPDL_INDEX () - op, Qnil);
 702           AFTER_POTENTIAL_GC ();
 703           break;
 704
 705         case Bunbind_all:
 706           /* To unbind back to the beginning of this frame.  Not used yet,
 707              but will be needed for tail-recursion elimination.  */
 708           BEFORE_POTENTIAL_GC ();
 709           unbind_to (count, Qnil);
 710           AFTER_POTENTIAL_GC ();
 711           break;
 712
 713         case Bgoto:
 714           MAYBE_GC ();
 715           BYTE_CODE_QUIT;
 716           op = FETCH2;    /* pc = FETCH2 loses since FETCH2 contains pc++ */
 717           CHECK_RANGE (op);
 718           stack.pc = stack.byte_string_start + op;
 719           break;
 720
 721         case Bgotoifnonnil:
 722           {
 723             Lisp_Object v1;
 724             MAYBE_GC ();
 725             op = FETCH2;
 726             v1 = POP;
 727             if (!NILP (v1))
 728               {
 729                 BYTE_CODE_QUIT;
 730                 CHECK_RANGE (op);
 731                 stack.pc = stack.byte_string_start + op;
 732               }
 733             break;
 734           }
 735
 736         case Bgotoifnilelsepop:
 737           MAYBE_GC ();
 738           op = FETCH2;
 739           if (NILP (TOP))
 740             {
 741               BYTE_CODE_QUIT;
 742               CHECK_RANGE (op);
 743               stack.pc = stack.byte_string_start + op;
 744             }
 745           else DISCARD (1);
 746           break;
 747
 748         case Bgotoifnonnilelsepop:
 749           MAYBE_GC ();
 750           op = FETCH2;
 751           if (!NILP (TOP))
 752             {
 753               BYTE_CODE_QUIT;
 754               CHECK_RANGE (op);
 755               stack.pc = stack.byte_string_start + op;
 756             }
 757           else DISCARD (1);
 758           break;
 759
 760         case BRgoto:
 761           MAYBE_GC ();
 762           BYTE_CODE_QUIT;
 763           stack.pc += (int) *stack.pc - 127;
 764           break;
 765
 766         case BRgotoifnil:
 767           {
 768             Lisp_Object v1;
 769             MAYBE_GC ();
 770             v1 = POP;
 771             if (NILP (v1))
 772               {
 773                 BYTE_CODE_QUIT;
 774                 stack.pc += (int) *stack.pc - 128;
 775               }
 776             stack.pc++;
 777             break;
 778           }
 779
 780         case BRgotoifnonnil:
 781           {
 782             Lisp_Object v1;
 783             MAYBE_GC ();
 784             v1 = POP;
 785             if (!NILP (v1))
 786               {
 787                 BYTE_CODE_QUIT;
 788                 stack.pc += (int) *stack.pc - 128;
 789               }
 790             stack.pc++;
 791             break;
 792           }
 793
 794         case BRgotoifnilelsepop:
 795           MAYBE_GC ();
 796           op = *stack.pc++;
 797           if (NILP (TOP))
 798             {
 799               BYTE_CODE_QUIT;
 800               stack.pc += op - 128;
 801             }
 802           else DISCARD (1);
 803           break;
 804
 805         case BRgotoifnonnilelsepop:
 806           MAYBE_GC ();
 807           op = *stack.pc++;
 808           if (!NILP (TOP))
 809             {
 810               BYTE_CODE_QUIT;
 811               stack.pc += op - 128;
 812             }
 813           else DISCARD (1);
 814           break;
 815
 816         case Breturn:
 817           result = POP;
 818           goto exit;
 819
 820         case Bdiscard:
 821           DISCARD (1);
 822           break;
 823
 824         case Bconstant2:
 825           PUSH (vectorp[FETCH2]);
 826           break;
 827
 828         case Bsave_excursion:
 829           record_unwind_protect (save_excursion_restore,
 830                                  save_excursion_save ());
 831           break;
 832
 833         case Bsave_current_buffer:
 834         case Bsave_current_buffer_1:
 835           record_unwind_protect (set_buffer_if_live, Fcurrent_buffer ());
 836           break;
 837
 838         case Bsave_window_excursion:
 839           BEFORE_POTENTIAL_GC ();
 840           TOP = Fsave_window_excursion (TOP);
 841           AFTER_POTENTIAL_GC ();
 842           break;
 843
 844         case Bsave_restriction:
 845           record_unwind_protect (save_restriction_restore,
 846                                  save_restriction_save ());
 847           break;
 848
 849         case Bcatch:
 850           {
 851             Lisp_Object v1;
 852             BEFORE_POTENTIAL_GC ();
 853             v1 = POP;
 854             TOP = internal_catch (TOP, Feval, v1);
 855             AFTER_POTENTIAL_GC ();
 856             break;
 857           }
 858
 859         case Bunwind_protect:
 860           record_unwind_protect (Fprogn, POP);
 861           break;
 862
 863         case Bcondition_case:
 864           {
 865             Lisp_Object handlers, body;
 866             handlers = POP;
 867             body = POP;
 868             BEFORE_POTENTIAL_GC ();
 869             TOP = internal_lisp_condition_case (TOP, body, handlers);
 870             AFTER_POTENTIAL_GC ();
 871             break;
 872           }
 873
 874         case Btemp_output_buffer_setup:
 875           BEFORE_POTENTIAL_GC ();
 876           CHECK_STRING (TOP);
 877           temp_output_buffer_setup (SDATA (TOP));
 878           AFTER_POTENTIAL_GC ();
 879           TOP = Vstandard_output;
 880           break;
 881
 882         case Btemp_output_buffer_show:
 883           {
 884             Lisp_Object v1;
 885             BEFORE_POTENTIAL_GC ();
 886             v1 = POP;
 887             temp_output_buffer_show (TOP);
 888             TOP = v1;
 889             /* pop binding of standard-output */
 890             unbind_to (SPECPDL_INDEX () - 1, Qnil);
 891             AFTER_POTENTIAL_GC ();
 892             break;
 893           }
 894
 895         case Bnth:
 896           {
 897             Lisp_Object v1, v2;
 898             BEFORE_POTENTIAL_GC ();
 899             v1 = POP;
 900             v2 = TOP;
 901             CHECK_NUMBER (v2);
 902             AFTER_POTENTIAL_GC ();
 903             op = XINT (v2);
 904             immediate_quit = 1;
 905             while (--op >= 0 && CONSP (v1))
 906               v1 = XCDR (v1);
 907             immediate_quit = 0;
 908             TOP = CAR (v1);
 909             break;
 910           }
 911
 912         case Bsymbolp:
 913           TOP = SYMBOLP (TOP) ? Qt : Qnil;
 914           break;
 915
 916         case Bconsp:
 917           TOP = CONSP (TOP) ? Qt : Qnil;
 918           break;
 919
 920         case Bstringp:
 921           TOP = STRINGP (TOP) ? Qt : Qnil;
 922           break;
 923
 924         case Blistp:
 925           TOP = CONSP (TOP) || NILP (TOP) ? Qt : Qnil;
 926           break;
 927
 928         case Bnot:
 929           TOP = NILP (TOP) ? Qt : Qnil;
 930           break;
 931
 932         case Bcons:
 933           {
 934             Lisp_Object v1;
 935             v1 = POP;
 936             TOP = Fcons (TOP, v1);
 937             break;
 938           }
 939
 940         case Blist1:
 941           TOP = Fcons (TOP, Qnil);
 942           break;
 943
 944         case Blist2:
 945           {
 946             Lisp_Object v1;
 947             v1 = POP;
 948             TOP = Fcons (TOP, Fcons (v1, Qnil));
 949             break;
 950           }
 951
 952         case Blist3:
 953           DISCARD (2);
 954           TOP = Flist (3, &TOP);
 955           break;
 956
 957         case Blist4:
 958           DISCARD (3);
 959           TOP = Flist (4, &TOP);
 960           break;
 961
 962         case BlistN:
 963           op = FETCH;
 964           DISCARD (op - 1);
 965           TOP = Flist (op, &TOP);
 966           break;
 967
 968         case Blength:
 969           BEFORE_POTENTIAL_GC ();
 970           TOP = Flength (TOP);
 971           AFTER_POTENTIAL_GC ();
 972           break;
 973
 974         case Baref:
 975           {
 976             Lisp_Object v1;
 977             BEFORE_POTENTIAL_GC ();
 978             v1 = POP;
 979             TOP = Faref (TOP, v1);
 980             AFTER_POTENTIAL_GC ();
 981             break;
 982           }
 983
 984         case Baset:
 985           {
 986             Lisp_Object v1, v2;
 987             BEFORE_POTENTIAL_GC ();
 988             v2 = POP; v1 = POP;
 989             TOP = Faset (TOP, v1, v2);
 990             AFTER_POTENTIAL_GC ();
 991             break;
 992           }
 993
 994         case Bsymbol_value:
 995           BEFORE_POTENTIAL_GC ();
 996           TOP = Fsymbol_value (TOP);
 997           AFTER_POTENTIAL_GC ();
 998           break;
 999
1000         case Bsymbol_function:
1001           BEFORE_POTENTIAL_GC ();
1002           TOP = Fsymbol_function (TOP);
1003           AFTER_POTENTIAL_GC ();
1004           break;
1005
1006         case Bset:
1007           {
1008             Lisp_Object v1;
1009             BEFORE_POTENTIAL_GC ();
1010             v1 = POP;
1011             TOP = Fset (TOP, v1);
1012             AFTER_POTENTIAL_GC ();
1013             break;
1014           }
1015
1016         case Bfset:
1017           {
1018             Lisp_Object v1;
1019             BEFORE_POTENTIAL_GC ();
1020             v1 = POP;
1021             TOP = Ffset (TOP, v1);
1022             AFTER_POTENTIAL_GC ();
1023             break;
1024           }
1025
1026         case Bget:
1027           {
1028             Lisp_Object v1;
1029             BEFORE_POTENTIAL_GC ();
1030             v1 = POP;
1031             TOP = Fget (TOP, v1);
1032             AFTER_POTENTIAL_GC ();
1033             break;
1034           }
1035
1036         case Bsubstring:
1037           {
1038             Lisp_Object v1, v2;
1039             BEFORE_POTENTIAL_GC ();
1040             v2 = POP; v1 = POP;
1041             TOP = Fsubstring (TOP, v1, v2);
1042             AFTER_POTENTIAL_GC ();
1043             break;
1044           }
1045
1046         case Bconcat2:
1047           BEFORE_POTENTIAL_GC ();
1048           DISCARD (1);
1049           TOP = Fconcat (2, &TOP);
1050           AFTER_POTENTIAL_GC ();
1051           break;
1052
1053         case Bconcat3:
1054           BEFORE_POTENTIAL_GC ();
1055           DISCARD (2);
1056           TOP = Fconcat (3, &TOP);
1057           AFTER_POTENTIAL_GC ();
1058           break;
1059
1060         case Bconcat4:
1061           BEFORE_POTENTIAL_GC ();
1062           DISCARD (3);
1063           TOP = Fconcat (4, &TOP);
1064           AFTER_POTENTIAL_GC ();
1065           break;
1066
1067         case BconcatN:
1068           op = FETCH;
1069           BEFORE_POTENTIAL_GC ();
1070           DISCARD (op - 1);
1071           TOP = Fconcat (op, &TOP);
1072           AFTER_POTENTIAL_GC ();
1073           break;
1074
1075         case Bsub1:
1076           {
1077             Lisp_Object v1;
1078             v1 = TOP;
1079             if (INTEGERP (v1))
1080               {
1081                 XSETINT (v1, XINT (v1) - 1);
1082                 TOP = v1;
1083               }
1084             else
1085               {
1086                 BEFORE_POTENTIAL_GC ();
1087                 TOP = Fsub1 (v1);
1088                 AFTER_POTENTIAL_GC ();
1089               }
1090             break;
1091           }
1092
1093         case Badd1:
1094           {
1095             Lisp_Object v1;
1096             v1 = TOP;
1097             if (INTEGERP (v1))
1098               {
1099                 XSETINT (v1, XINT (v1) + 1);
1100                 TOP = v1;
1101               }
1102             else
1103               {
1104                 BEFORE_POTENTIAL_GC ();
1105                 TOP = Fadd1 (v1);
1106                 AFTER_POTENTIAL_GC ();
1107               }
1108             break;
1109           }
1110
1111         case Beqlsign:
1112           {
1113             Lisp_Object v1, v2;
1114             BEFORE_POTENTIAL_GC ();
1115             v2 = POP; v1 = TOP;
1116             CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v1);
1117             CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v2);
1118             AFTER_POTENTIAL_GC ();
1119             if (FLOATP (v1) || FLOATP (v2))
1120               {
1121                 double f1, f2;
1122
1123                 f1 = (FLOATP (v1) ? XFLOAT_DATA (v1) : XINT (v1));
1124                 f2 = (FLOATP (v2) ? XFLOAT_DATA (v2) : XINT (v2));
1125                 TOP = (f1 == f2 ? Qt : Qnil);
1126               }
1127             else
1128               TOP = (XINT (v1) == XINT (v2) ? Qt : Qnil);
1129             break;
1130           }
1131
1132         case Bgtr:
1133           {
1134             Lisp_Object v1;
1135             BEFORE_POTENTIAL_GC ();
1136             v1 = POP;
1137             TOP = Fgtr (TOP, v1);
1138             AFTER_POTENTIAL_GC ();
1139             break;
1140           }
1141
1142         case Blss:
1143           {
1144             Lisp_Object v1;
1145             BEFORE_POTENTIAL_GC ();
1146             v1 = POP;
1147             TOP = Flss (TOP, v1);
1148             AFTER_POTENTIAL_GC ();
1149             break;
1150           }
1151
1152         case Bleq:
1153           {
1154             Lisp_Object v1;
1155             BEFORE_POTENTIAL_GC ();
1156             v1 = POP;
1157             TOP = Fleq (TOP, v1);
1158             AFTER_POTENTIAL_GC ();
1159             break;
1160           }
1161
1162         case Bgeq:
1163           {
1164             Lisp_Object v1;
1165             BEFORE_POTENTIAL_GC ();
1166             v1 = POP;
1167             TOP = Fgeq (TOP, v1);
1168             AFTER_POTENTIAL_GC ();
1169             break;
1170           }
1171
1172         case Bdiff:
1173           BEFORE_POTENTIAL_GC ();
1174           DISCARD (1);
1175           TOP = Fminus (2, &TOP);
1176           AFTER_POTENTIAL_GC ();
1177           break;
1178
1179         case Bnegate:
1180           {
1181             Lisp_Object v1;
1182             v1 = TOP;
1183             if (INTEGERP (v1))
1184               {
1185                 XSETINT (v1, - XINT (v1));
1186                 TOP = v1;
1187               }
1188             else
1189               {
1190                 BEFORE_POTENTIAL_GC ();
1191                 TOP = Fminus (1, &TOP);
1192                 AFTER_POTENTIAL_GC ();
1193               }
1194             break;
1195           }
1196
1197         case Bplus:
1198           BEFORE_POTENTIAL_GC ();
1199           DISCARD (1);
1200           TOP = Fplus (2, &TOP);
1201           AFTER_POTENTIAL_GC ();
1202           break;
1203
1204         case Bmax:
1205           BEFORE_POTENTIAL_GC ();
1206           DISCARD (1);
1207           TOP = Fmax (2, &TOP);
1208           AFTER_POTENTIAL_GC ();
1209           break;
1210
1211         case Bmin:
1212           BEFORE_POTENTIAL_GC ();
1213           DISCARD (1);
1214           TOP = Fmin (2, &TOP);
1215           AFTER_POTENTIAL_GC ();
1216           break;
1217
1218         case Bmult:
1219           BEFORE_POTENTIAL_GC ();
1220           DISCARD (1);
1221           TOP = Ftimes (2, &TOP);
1222           AFTER_POTENTIAL_GC ();
1223           break;
1224
1225         case Bquo:
1226           BEFORE_POTENTIAL_GC ();
1227           DISCARD (1);
1228           TOP = Fquo (2, &TOP);
1229           AFTER_POTENTIAL_GC ();
1230           break;
1231
1232         case Brem:
1233           {
1234             Lisp_Object v1;
1235             BEFORE_POTENTIAL_GC ();
1236             v1 = POP;
1237             TOP = Frem (TOP, v1);
1238             AFTER_POTENTIAL_GC ();
1239             break;
1240           }
1241
1242         case Bpoint:
1243           {
1244             Lisp_Object v1;
1245             XSETFASTINT (v1, PT);
1246             PUSH (v1);
1247             break;
1248           }
1249
1250         case Bgoto_char:
1251           BEFORE_POTENTIAL_GC ();
1252           TOP = Fgoto_char (TOP);
1253           AFTER_POTENTIAL_GC ();
1254           break;
1255
1256         case Binsert:
1257           BEFORE_POTENTIAL_GC ();
1258           TOP = Finsert (1, &TOP);
1259           AFTER_POTENTIAL_GC ();
1260           break;
1261
1262         case BinsertN:
1263           op = FETCH;
1264           BEFORE_POTENTIAL_GC ();
1265           DISCARD (op - 1);
1266           TOP = Finsert (op, &TOP);
1267           AFTER_POTENTIAL_GC ();
1268           break;
1269
1270         case Bpoint_max:
1271           {
1272             Lisp_Object v1;
1273             XSETFASTINT (v1, ZV);
1274             PUSH (v1);
1275             break;
1276           }
1277
1278         case Bpoint_min:
1279           {
1280             Lisp_Object v1;
1281             XSETFASTINT (v1, BEGV);
1282             PUSH (v1);
1283             break;
1284           }
1285
1286         case Bchar_after:
1287           BEFORE_POTENTIAL_GC ();
1288           TOP = Fchar_after (TOP);
1289           AFTER_POTENTIAL_GC ();
1290           break;
1291
1292         case Bfollowing_char:
1293           {
1294             Lisp_Object v1;
1295             BEFORE_POTENTIAL_GC ();
1296             v1 = Ffollowing_char ();
1297             AFTER_POTENTIAL_GC ();
1298             PUSH (v1);
1299             break;
1300           }
1301
1302         case Bpreceding_char:
1303           {
1304             Lisp_Object v1;
1305             BEFORE_POTENTIAL_GC ();
1306             v1 = Fprevious_char ();
1307             AFTER_POTENTIAL_GC ();
1308             PUSH (v1);
1309             break;
1310           }
1311
1312         case Bcurrent_column:
1313           {
1314             Lisp_Object v1;
1315             BEFORE_POTENTIAL_GC ();
1316             XSETFASTINT (v1, (int) current_column ()); /* iftc */
1317             AFTER_POTENTIAL_GC ();
1318             PUSH (v1);
1319             break;
1320           }
1321
1322         case Bindent_to:
1323           BEFORE_POTENTIAL_GC ();
1324           TOP = Findent_to (TOP, Qnil);
1325           AFTER_POTENTIAL_GC ();
1326           break;
1327
1328         case Beolp:
1329           PUSH (Feolp ());
1330           break;
1331
1332         case Beobp:
1333           PUSH (Feobp ());
1334           break;
1335
1336         case Bbolp:
1337           PUSH (Fbolp ());
1338           break;
1339
1340         case Bbobp:
1341           PUSH (Fbobp ());
1342           break;
1343
1344         case Bcurrent_buffer:
1345           PUSH (Fcurrent_buffer ());
1346           break;
1347
1348         case Bset_buffer:
1349           BEFORE_POTENTIAL_GC ();
1350           TOP = Fset_buffer (TOP);
1351           AFTER_POTENTIAL_GC ();
1352           break;
1353
1354         case Binteractive_p:
1355           PUSH (Finteractive_p ());
1356           break;
1357
1358         case Bforward_char:
1359           BEFORE_POTENTIAL_GC ();
1360           TOP = Fforward_char (TOP);
1361           AFTER_POTENTIAL_GC ();
1362           break;
1363
1364         case Bforward_word:
1365           BEFORE_POTENTIAL_GC ();
1366           TOP = Fforward_word (TOP);
1367           AFTER_POTENTIAL_GC ();
1368           break;
1369
1370         case Bskip_chars_forward:
1371           {
1372             Lisp_Object v1;
1373             BEFORE_POTENTIAL_GC ();
1374             v1 = POP;
1375             TOP = Fskip_chars_forward (TOP, v1);
1376             AFTER_POTENTIAL_GC ();
1377             break;
1378           }
1379
1380         case Bskip_chars_backward:
1381           {
1382             Lisp_Object v1;
1383             BEFORE_POTENTIAL_GC ();
1384             v1 = POP;
1385             TOP = Fskip_chars_backward (TOP, v1);
1386             AFTER_POTENTIAL_GC ();
1387             break;
1388           }
1389
1390         case Bforward_line:
1391           BEFORE_POTENTIAL_GC ();
1392           TOP = Fforward_line (TOP);
1393           AFTER_POTENTIAL_GC ();
1394           break;
1395
1396         case Bchar_syntax:
1397           BEFORE_POTENTIAL_GC ();
1398           CHECK_NUMBER (TOP);
1399           AFTER_POTENTIAL_GC ();
1400           XSETFASTINT (TOP, syntax_code_spec[(int) SYNTAX (XINT (TOP))]);
1401           break;
1402
1403         case Bbuffer_substring:
1404           {
1405             Lisp_Object v1;
1406             BEFORE_POTENTIAL_GC ();
1407             v1 = POP;
1408             TOP = Fbuffer_substring (TOP, v1);
1409             AFTER_POTENTIAL_GC ();
1410             break;
1411           }
1412
1413         case Bdelete_region:
1414           {
1415             Lisp_Object v1;
1416             BEFORE_POTENTIAL_GC ();
1417             v1 = POP;
1418             TOP = Fdelete_region (TOP, v1);
1419             AFTER_POTENTIAL_GC ();
1420             break;
1421           }
1422
1423         case Bnarrow_to_region:
1424           {
1425             Lisp_Object v1;
1426             BEFORE_POTENTIAL_GC ();
1427             v1 = POP;
1428             TOP = Fnarrow_to_region (TOP, v1);
1429             AFTER_POTENTIAL_GC ();
1430             break;
1431           }
1432
1433         case Bwiden:
1434           BEFORE_POTENTIAL_GC ();
1435           PUSH (Fwiden ());
1436           AFTER_POTENTIAL_GC ();
1437           break;
1438
1439         case Bend_of_line:
1440           BEFORE_POTENTIAL_GC ();
1441           TOP = Fend_of_line (TOP);
1442           AFTER_POTENTIAL_GC ();
1443           break;
1444
1445         case Bset_marker:
1446           {
1447             Lisp_Object v1, v2;
1448             BEFORE_POTENTIAL_GC ();
1449             v1 = POP;
1450             v2 = POP;
1451             TOP = Fset_marker (TOP, v2, v1);
1452             AFTER_POTENTIAL_GC ();
1453             break;
1454           }
1455
1456         case Bmatch_beginning:
1457           BEFORE_POTENTIAL_GC ();
1458           TOP = Fmatch_beginning (TOP);
1459           AFTER_POTENTIAL_GC ();
1460           break;
1461
1462         case Bmatch_end:
1463           BEFORE_POTENTIAL_GC ();
1464           TOP = Fmatch_end (TOP);
1465           AFTER_POTENTIAL_GC ();
1466           break;
1467
1468         case Bupcase:
1469           BEFORE_POTENTIAL_GC ();
1470           TOP = Fupcase (TOP);
1471           AFTER_POTENTIAL_GC ();
1472           break;
1473
1474         case Bdowncase:
1475           BEFORE_POTENTIAL_GC ();
1476           TOP = Fdowncase (TOP);
1477           AFTER_POTENTIAL_GC ();
1478         break;
1479
1480         case Bstringeqlsign:
1481           {
1482             Lisp_Object v1;
1483             BEFORE_POTENTIAL_GC ();
1484             v1 = POP;
1485             TOP = Fstring_equal (TOP, v1);
1486             AFTER_POTENTIAL_GC ();
1487             break;
1488           }
1489
1490         case Bstringlss:
1491           {
1492             Lisp_Object v1;
1493             BEFORE_POTENTIAL_GC ();
1494             v1 = POP;
1495             TOP = Fstring_lessp (TOP, v1);
1496             AFTER_POTENTIAL_GC ();
1497             break;
1498           }
1499
1500         case Bequal:
1501           {
1502             Lisp_Object v1;
1503             v1 = POP;
1504             TOP = Fequal (TOP, v1);
1505             break;
1506           }
1507
1508         case Bnthcdr:
1509           {
1510             Lisp_Object v1;
1511             BEFORE_POTENTIAL_GC ();
1512             v1 = POP;
1513             TOP = Fnthcdr (TOP, v1);
1514             AFTER_POTENTIAL_GC ();
1515             break;
1516           }
1517
1518         case Belt:
1519           {
1520             Lisp_Object v1, v2;
1521             if (CONSP (TOP))
1522               {
1523                 /* Exchange args and then do nth.  */
1524                 BEFORE_POTENTIAL_GC ();
1525                 v2 = POP;
1526                 v1 = TOP;
1527                 CHECK_NUMBER (v2);
1528                 AFTER_POTENTIAL_GC ();
1529                 op = XINT (v2);
1530                 immediate_quit = 1;
1531                 while (--op >= 0 && CONSP (v1))
1532                   v1 = XCDR (v1);
1533                 immediate_quit = 0;
1534                 TOP = CAR (v1);
1535               }
1536             else
1537               {
1538                 BEFORE_POTENTIAL_GC ();
1539                 v1 = POP;
1540                 TOP = Felt (TOP, v1);
1541                 AFTER_POTENTIAL_GC ();
1542               }
1543             break;
1544           }
1545
1546         case Bmember:
1547           {
1548             Lisp_Object v1;
1549             BEFORE_POTENTIAL_GC ();
1550             v1 = POP;
1551             TOP = Fmember (TOP, v1);
1552             AFTER_POTENTIAL_GC ();
1553             break;
1554           }
1555
1556         case Bassq:
1557           {
1558             Lisp_Object v1;
1559             BEFORE_POTENTIAL_GC ();
1560             v1 = POP;
1561             TOP = Fassq (TOP, v1);
1562             AFTER_POTENTIAL_GC ();
1563             break;
1564           }
1565
1566         case Bnreverse:
1567           BEFORE_POTENTIAL_GC ();
1568           TOP = Fnreverse (TOP);
1569           AFTER_POTENTIAL_GC ();
1570           break;
1571
1572         case Bsetcar:
1573           {
1574             Lisp_Object v1;
1575             BEFORE_POTENTIAL_GC ();
1576             v1 = POP;
1577             TOP = Fsetcar (TOP, v1);
1578             AFTER_POTENTIAL_GC ();
1579             break;
1580           }
1581
1582         case Bsetcdr:
1583           {
1584             Lisp_Object v1;
1585             BEFORE_POTENTIAL_GC ();
1586             v1 = POP;
1587             TOP = Fsetcdr (TOP, v1);
1588             AFTER_POTENTIAL_GC ();
1589             break;
1590           }
1591
1592         case Bcar_safe:
1593           {
1594             Lisp_Object v1;
1595             v1 = TOP;
1596             TOP = CAR_SAFE (v1);
1597             break;
1598           }
1599
1600         case Bcdr_safe:
1601           {
1602             Lisp_Object v1;
1603             v1 = TOP;
1604             TOP = CDR_SAFE (v1);
1605             break;
1606           }
1607
1608         case Bnconc:
1609           BEFORE_POTENTIAL_GC ();
1610           DISCARD (1);
1611           TOP = Fnconc (2, &TOP);
1612           AFTER_POTENTIAL_GC ();
1613           break;
1614
1615         case Bnumberp:
1616           TOP = (NUMBERP (TOP) ? Qt : Qnil);
1617           break;
1618
1619         case Bintegerp:
1620           TOP = INTEGERP (TOP) ? Qt : Qnil;
1621           break;
1622
1623 #ifdef BYTE_CODE_SAFE
1624         case Bset_mark:
1625           BEFORE_POTENTIAL_GC ();
1626           error ("set-mark is an obsolete bytecode");
1627           AFTER_POTENTIAL_GC ();
1628           break;
1629         case Bscan_buffer:
1630           BEFORE_POTENTIAL_GC ();
1631           error ("scan-buffer is an obsolete bytecode");
1632           AFTER_POTENTIAL_GC ();
1633           break;
1634 #endif
1635
1636         case 0:
1637           abort ();
1638
1639         case 255:
1640         default:
1641 #ifdef BYTE_CODE_SAFE
1642           if (op < Bconstant)
1643             {
1644               abort ();
1645             }
1646           if ((op -= Bconstant) >= const_length)
1647             {
1648               abort ();
1649             }
1650           PUSH (vectorp[op]);
1651 #else
1652           PUSH (vectorp[op - Bconstant]);
1653 #endif
1654         }
1655     }
1656
1657  exit:
1658
1659   byte_stack_list = byte_stack_list->next;
1660
1661   /* Binds and unbinds are supposed to be compiled balanced.  */
1662   if (SPECPDL_INDEX () != count)
1663 #ifdef BYTE_CODE_SAFE
1664     error ("binding stack not balanced (serious byte compiler bug)");
1665 #else
1666     abort ();
1667 #endif
1668
1669   return result;
1670 }
1671
1672 void
1673 syms_of_bytecode ()
1674 {
1675   Qbytecode = intern ("byte-code");
1676   staticpro (&Qbytecode);
1677
1678   defsubr (&Sbyte_code);
1679
1680 #ifdef BYTE_CODE_METER
1681
1682   DEFVAR_LISP ("byte-code-meter", &Vbyte_code_meter,
1683                doc: /* A vector of vectors which holds a histogram of byte-code usage.
1684 \(aref (aref byte-code-meter 0) CODE) indicates how many times the byte
1685 opcode CODE has been executed.
1686 \(aref (aref byte-code-meter CODE1) CODE2), where CODE1 is not 0,
1687 indicates how many times the byte opcodes CODE1 and CODE2 have been
1688 executed in succession.  */);
1689
1690   DEFVAR_BOOL ("byte-metering-on", &byte_metering_on,
1691                doc: /* If non-nil, keep profiling information on byte code usage.
1692 The variable byte-code-meter indicates how often each byte opcode is used.
1693 If a symbol has a property named `byte-code-meter' whose value is an
1694 integer, it is incremented each time that symbol's function is called.  */);
1695
1696   byte_metering_on = 0;
1697   Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
1698   Qbyte_code_meter = intern ("byte-code-meter");
1699   staticpro (&Qbyte_code_meter);
1700   {
1701     int i = 256;
1702     while (i--)
1703       XVECTOR (Vbyte_code_meter)->contents[i] =
1704         Fmake_vector (make_number (256), make_number (0));
1705   }
1706 #endif
1707 }
1708
1709 /* arch-tag: b9803b6f-1ed6-4190-8adf-33fd3a9d10e9
1710    (do not change this comment) */