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, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.
  20
  21 hacked on by jwz@lucid.com 17-jun-91
  22   o  added a compile-time switch to turn on simple sanity checking;
  23   o  put back the obsolete byte-codes for error-detection;
  24   o  added a new instruction, unbind_all, which I will use for
  25      tail-recursion elimination;
  26   o  made temp_output_buffer_show be called with the right number
  27      of args;
  28   o  made the new bytecodes be called with args in the right order;
  29   o  added metering support.
  30
  31 by Hallvard:
  32   o  added relative jump instructions;
  33   o  all conditionals now only do QUIT if they jump.
  34  */
  35
  36 #include <config.h>
  37 #include "lisp.h"
  38 #include "buffer.h"
  39 #include "charset.h"
  40 #include "syntax.h"
  41
  42 /*
  43  * define BYTE_CODE_SAFE to enable some minor sanity checking (useful for
  44  * debugging the byte compiler...)
  45  *
  46  * define BYTE_CODE_METER to enable generation of a byte-op usage histogram.
  47  */
  48 /* #define BYTE_CODE_SAFE */
  49 /* #define BYTE_CODE_METER */
  50
  51 \f
  52 #ifdef BYTE_CODE_METER
  53
  54 Lisp_Object Vbyte_code_meter, Qbyte_code_meter;
  55 int byte_metering_on;
  56
  57 #define METER_2(code1, code2) \
  58   XFASTINT (XVECTOR (XVECTOR (Vbyte_code_meter)->contents[(code1)]) \
  59             ->contents[(code2)])
  60
  61 #define METER_1(code) METER_2 (0, (code))
  62
  63 #define METER_CODE(last_code, this_code)                        \
  64 {                                                               \
  65   if (byte_metering_on)                                         \
  66     {                                                           \
  67       if (METER_1 (this_code) != ((1<<VALBITS)-1))              \
  68         METER_1 (this_code)++;                                  \
  69       if (last_code                                             \
  70           && METER_2 (last_code, this_code) != ((1<<VALBITS)-1))\
  71         METER_2 (last_code, this_code)++;                       \
  72     }                                                           \
  73 }
  74
  75 #else /* no BYTE_CODE_METER */
  76
  77 #define METER_CODE(last_code, this_code)
  78
  79 #endif /* no BYTE_CODE_METER */
  80 \f
  81
  82 Lisp_Object Qbytecode;
  83
  84 /*  Byte codes: */
  85
  86 #define Bvarref 010
  87 #define Bvarset 020
  88 #define Bvarbind 030
  89 #define Bcall 040
  90 #define Bunbind 050
  91
  92 #define Bnth 070
  93 #define Bsymbolp 071
  94 #define Bconsp 072
  95 #define Bstringp 073
  96 #define Blistp 074
  97 #define Beq 075
  98 #define Bmemq 076
  99 #define Bnot 077
 100 #define Bcar 0100
 101 #define Bcdr 0101
 102 #define Bcons 0102
 103 #define Blist1 0103
 104 #define Blist2 0104
 105 #define Blist3 0105
 106 #define Blist4 0106
 107 #define Blength 0107
 108 #define Baref 0110
 109 #define Baset 0111
 110 #define Bsymbol_value 0112
 111 #define Bsymbol_function 0113
 112 #define Bset 0114
 113 #define Bfset 0115
 114 #define Bget 0116
 115 #define Bsubstring 0117
 116 #define Bconcat2 0120
 117 #define Bconcat3 0121
 118 #define Bconcat4 0122
 119 #define Bsub1 0123
 120 #define Badd1 0124
 121 #define Beqlsign 0125
 122 #define Bgtr 0126
 123 #define Blss 0127
 124 #define Bleq 0130
 125 #define Bgeq 0131
 126 #define Bdiff 0132
 127 #define Bnegate 0133
 128 #define Bplus 0134
 129 #define Bmax 0135
 130 #define Bmin 0136
 131 #define Bmult 0137
 132
 133 #define Bpoint 0140
 134 /* Was Bmark in v17.  */
 135 #define Bsave_current_buffer 0141
 136 #define Bgoto_char 0142
 137 #define Binsert 0143
 138 #define Bpoint_max 0144
 139 #define Bpoint_min 0145
 140 #define Bchar_after 0146
 141 #define Bfollowing_char 0147
 142 #define Bpreceding_char 0150
 143 #define Bcurrent_column 0151
 144 #define Bindent_to 0152
 145 #define Bscan_buffer 0153 /* No longer generated as of v18 */
 146 #define Beolp 0154
 147 #define Beobp 0155
 148 #define Bbolp 0156
 149 #define Bbobp 0157
 150 #define Bcurrent_buffer 0160
 151 #define Bset_buffer 0161
 152 #define Bsave_current_buffer_1 0162 /* Replacing Bsave_current_buffer.  */
 153 #define Bread_char 0162 /* No longer generated as of v19 */
 154 #define Bset_mark 0163 /* this loser is no longer generated as of v18 */
 155 #define Binteractive_p 0164 /* Needed since interactive-p takes unevalled args */
 156
 157 #define Bforward_char 0165
 158 #define Bforward_word 0166
 159 #define Bskip_chars_forward 0167
 160 #define Bskip_chars_backward 0170
 161 #define Bforward_line 0171
 162 #define Bchar_syntax 0172
 163 #define Bbuffer_substring 0173
 164 #define Bdelete_region 0174
 165 #define Bnarrow_to_region 0175
 166 #define Bwiden 0176
 167 #define Bend_of_line 0177
 168
 169 #define Bconstant2 0201
 170 #define Bgoto 0202
 171 #define Bgotoifnil 0203
 172 #define Bgotoifnonnil 0204
 173 #define Bgotoifnilelsepop 0205
 174 #define Bgotoifnonnilelsepop 0206
 175 #define Breturn 0207
 176 #define Bdiscard 0210
 177 #define Bdup 0211
 178
 179 #define Bsave_excursion 0212
 180 #define Bsave_window_excursion 0213
 181 #define Bsave_restriction 0214
 182 #define Bcatch 0215
 183
 184 #define Bunwind_protect 0216
 185 #define Bcondition_case 0217
 186 #define Btemp_output_buffer_setup 0220
 187 #define Btemp_output_buffer_show 0221
 188
 189 #define Bunbind_all 0222
 190
 191 #define Bset_marker 0223
 192 #define Bmatch_beginning 0224
 193 #define Bmatch_end 0225
 194 #define Bupcase 0226
 195 #define Bdowncase 0227
 196
 197 #define Bstringeqlsign 0230
 198 #define Bstringlss 0231
 199 #define Bequal 0232
 200 #define Bnthcdr 0233
 201 #define Belt 0234
 202 #define Bmember 0235
 203 #define Bassq 0236
 204 #define Bnreverse 0237
 205 #define Bsetcar 0240
 206 #define Bsetcdr 0241
 207 #define Bcar_safe 0242
 208 #define Bcdr_safe 0243
 209 #define Bnconc 0244
 210 #define Bquo 0245
 211 #define Brem 0246
 212 #define Bnumberp 0247
 213 #define Bintegerp 0250
 214
 215 #define BRgoto 0252
 216 #define BRgotoifnil 0253
 217 #define BRgotoifnonnil 0254
 218 #define BRgotoifnilelsepop 0255
 219 #define BRgotoifnonnilelsepop 0256
 220
 221 #define BlistN 0257
 222 #define BconcatN 0260
 223 #define BinsertN 0261
 224
 225 #define Bconstant 0300
 226 #define CONSTANTLIM 0100
 227
 228 \f
 229 /* Structure describing a value stack used during byte-code execution
 230    in Fbyte_code.  */
 231
 232 struct byte_stack
 233 {
 234   /* Program counter.  This points into the byte_string below
 235      and is relocated when that string is relocated.  */
 236   unsigned char *pc;
 237
 238   /* Top and bottom of stack.  The bottom points to an area of memory
 239      allocated with alloca in Fbyte_code.  */
 240   Lisp_Object *top, *bottom;
 241
 242   /* The string containing the byte-code, and its current address.
 243      Storing this here protects it from GC because mark_byte_stack
 244      marks it.  */
 245   Lisp_Object byte_string;
 246   unsigned char *byte_string_start;
 247
 248   /* The vector of constants used during byte-code execution.  Storing
 249      this here protects it from GC because mark_byte_stack marks it.  */
 250   Lisp_Object constants;
 251
 252   /* Next entry in byte_stack_list.  */
 253   struct byte_stack *next;
 254 };
 255
 256 /* A list of currently active byte-code execution value stacks.
 257    Fbyte_code adds an entry to the head of this list before it starts
 258    processing byte-code, and it removed the entry again when it is
 259    done.  Signalling an error truncates the list analoguous to
 260    gcprolist.  */
 261
 262 struct byte_stack *byte_stack_list;
 263
 264 \f
 265 /* Mark objects on byte_stack_list.  Called during GC.  */
 266
 267 void
 268 mark_byte_stack ()
 269 {
 270   struct byte_stack *stack;
 271   Lisp_Object *obj;
 272
 273   for (stack = byte_stack_list; stack; stack = stack->next)
 274     {
 275       if (!stack->top)
 276         abort ();
 277
 278       for (obj = stack->bottom; obj <= stack->top; ++obj)
 279         if (!XMARKBIT (*obj))
 280           {
 281             mark_object (obj);
 282             XMARK (*obj);
 283           }
 284
 285       if (!XMARKBIT (stack->byte_string))
 286         {
 287           mark_object (&stack->byte_string);
 288           XMARK (stack->byte_string);
 289         }
 290
 291       if (!XMARKBIT (stack->constants))
 292         {
 293           mark_object (&stack->constants);
 294           XMARK (stack->constants);
 295         }
 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   Lisp_Object *obj;
 308
 309   for (stack = byte_stack_list; stack; stack = stack->next)
 310     {
 311       for (obj = stack->bottom; obj <= stack->top; ++obj)
 312         XUNMARK (*obj);
 313
 314       XUNMARK (stack->byte_string);
 315       XUNMARK (stack->constants);
 316
 317       if (stack->byte_string_start != XSTRING (stack->byte_string)->data)
 318         {
 319           int offset = stack->pc - stack->byte_string_start;
 320           stack->byte_string_start = XSTRING (stack->byte_string)->data;
 321           stack->pc = stack->byte_string_start + offset;
 322         }
 323     }
 324 }
 325
 326 \f
 327 /* Fetch the next byte from the bytecode stream */
 328
 329 #define FETCH *stack.pc++
 330
 331 /* Fetch two bytes from the bytecode stream and make a 16-bit number
 332    out of them */
 333
 334 #define FETCH2 (op = FETCH, op + (FETCH << 8))
 335
 336 /* Push x onto the execution stack.  This used to be #define PUSH(x)
 337    (*++stackp = (x)) This oddity is necessary because Alliant can't be
 338    bothered to compile the preincrement operator properly, as of 4/91.
 339    -JimB */
 340
 341 #define PUSH(x) (top++, *top = (x))
 342
 343 /* Pop a value off the execution stack.  */
 344
 345 #define POP (*top--)
 346
 347 /* Discard n values from the execution stack.  */
 348
 349 #define DISCARD(n) (top -= (n))
 350
 351 /* Get the value which is at the top of the execution stack, but don't
 352    pop it. */
 353
 354 #define TOP (*top)
 355
 356 /* Actions that must be performed before and after calling a function
 357    that might GC.  */
 358
 359 #define BEFORE_POTENTIAL_GC()   stack.top = top
 360 #define AFTER_POTENTIAL_GC()    stack.top = NULL
 361
 362 /* Garbage collect if we have consed enough since the last time.
 363    We do this at every branch, to avoid loops that never GC.  */
 364
 365 #define MAYBE_GC()                              \
 366   if (consing_since_gc > gc_cons_threshold)     \
 367     {                                           \
 368       BEFORE_POTENTIAL_GC ();                   \
 369       Fgarbage_collect ();                      \
 370       AFTER_POTENTIAL_GC ();                    \
 371     }                                           \
 372   else
 373
 374 /* Check for jumping out of range.  */
 375
 376 #ifdef BYTE_CODE_SAFE
 377
 378 #define CHECK_RANGE(ARG) \
 379   if (ARG >= bytestr_length) abort ()
 380
 381 #else /* not BYTE_CODE_SAFE */
 382
 383 #define CHECK_RANGE(ARG)
 384
 385 #endif /* not BYTE_CODE_SAFE */
 386
 387
 388 DEFUN ("byte-code", Fbyte_code, Sbyte_code, 3, 3, 0,
 389   "Function used internally in byte-compiled code.\n\
 390 The first argument, BYTESTR, is a string of byte code;\n\
 391 the second, VECTOR, a vector of constants;\n\
 392 the third, MAXDEPTH, the maximum stack depth used in this function.\n\
 393 If the third argument is incorrect, Emacs may crash.")
 394   (bytestr, vector, maxdepth)
 395      Lisp_Object bytestr, vector, maxdepth;
 396 {
 397   int count = specpdl_ptr - specpdl;
 398 #ifdef BYTE_CODE_METER
 399   int this_op = 0;
 400   int prev_op;
 401 #endif
 402   int op;
 403   /* Lisp_Object v1, v2; */
 404   Lisp_Object *vectorp = XVECTOR (vector)->contents;
 405 #ifdef BYTE_CODE_SAFE
 406   int const_length = XVECTOR (vector)->size;
 407   Lisp_Object *stacke;
 408 #endif
 409   int bytestr_length = STRING_BYTES (XSTRING (bytestr));
 410   struct byte_stack stack;
 411   Lisp_Object *top;
 412   Lisp_Object result;
 413
 414   CHECK_STRING (bytestr, 0);
 415   if (!VECTORP (vector))
 416     vector = wrong_type_argument (Qvectorp, vector);
 417   CHECK_NUMBER (maxdepth, 2);
 418
 419   stack.byte_string = bytestr;
 420   stack.pc = stack.byte_string_start = XSTRING (bytestr)->data;
 421   stack.constants = vector;
 422   stack.bottom = (Lisp_Object *) alloca (XFASTINT (maxdepth)
 423                                          * sizeof (Lisp_Object));
 424   top = stack.bottom - 1;
 425   stack.top = NULL;
 426   stack.next = byte_stack_list;
 427   byte_stack_list = &stack;
 428
 429 #ifdef BYTE_CODE_SAFE
 430   stacke = stack.bottom - 1 + XFASTINT (maxdepth);
 431 #endif
 432
 433   while (1)
 434     {
 435 #ifdef BYTE_CODE_SAFE
 436       if (top > stacks)
 437         error ("Byte code stack overflow (byte compiler bug), pc %d, depth %d",
 438                stack.pc - stack.byte_string_start, stacke - top);
 439       else if (top < stack.bottom - 1)
 440         error ("Byte code stack underflow (byte compiler bug), pc %d",
 441                stack.pc - stack.byte_string_start);
 442 #endif
 443
 444 #ifdef BYTE_CODE_METER
 445       prev_op = this_op;
 446       this_op = op = FETCH;
 447       METER_CODE (prev_op, op);
 448 #else
 449       op = FETCH;
 450 #endif
 451
 452       switch (op)
 453         {
 454         case Bvarref + 7:
 455           op = FETCH2;
 456           goto varref;
 457
 458         case Bvarref:
 459         case Bvarref + 1:
 460         case Bvarref + 2:
 461         case Bvarref + 3:
 462         case Bvarref + 4:
 463         case Bvarref + 5:
 464           op = op - Bvarref;
 465           goto varref;
 466
 467         /* This seems to be the most frequently executed byte-code
 468            among the Bvarref's, so avoid a goto here.  */
 469         case Bvarref+6:
 470           op = FETCH;
 471         varref:
 472           {
 473             Lisp_Object v1, v2;
 474
 475             v1 = vectorp[op];
 476             if (SYMBOLP (v1))
 477               {
 478                 v2 = XSYMBOL (v1)->value;
 479                 if (MISCP (v2) || EQ (v2, Qunbound))
 480                   v2 = Fsymbol_value (v1);
 481               }
 482             else
 483               v2 = Fsymbol_value (v1);
 484             PUSH (v2);
 485             break;
 486           }
 487
 488         case Bgotoifnil:
 489           MAYBE_GC ();
 490           op = FETCH2;
 491           if (NILP (POP))
 492             {
 493               QUIT;
 494               CHECK_RANGE (op);
 495               stack.pc = stack.byte_string_start + op;
 496             }
 497           break;
 498
 499         case Bcar:
 500           {
 501             Lisp_Object v1;
 502             v1 = TOP;
 503             if (CONSP (v1))
 504               TOP = XCAR (v1);
 505             else if (NILP (v1))
 506               TOP = Qnil;
 507             else
 508               Fcar (wrong_type_argument (Qlistp, v1));
 509             break;
 510           }
 511
 512         case Beq:
 513           {
 514             Lisp_Object v1;
 515             v1 = POP;
 516             TOP = EQ (v1, TOP) ? Qt : Qnil;
 517             break;
 518           }
 519
 520         case Bmemq:
 521           {
 522             Lisp_Object v1;
 523             v1 = POP;
 524             TOP = Fmemq (TOP, v1);
 525             break;
 526           }
 527
 528         case Bcdr:
 529           {
 530             Lisp_Object v1;
 531             v1 = TOP;
 532             if (CONSP (v1))
 533               TOP = XCDR (v1);
 534             else if (NILP (v1))
 535               TOP = Qnil;
 536             else
 537               Fcdr (wrong_type_argument (Qlistp, v1));
 538             break;
 539           }
 540
 541         case Bvarset+7:
 542           op = FETCH2;
 543           goto varset;
 544
 545         case Bvarset: case Bvarset+1: case Bvarset+2: case Bvarset+3:
 546         case Bvarset+4: case Bvarset+5:
 547           op -= Bvarset;
 548           goto varset;
 549
 550         case Bvarset+6:
 551           op = FETCH;
 552         varset:
 553           set_internal (vectorp[op], POP, 0);
 554           /* Fset (vectorp[op], POP); */
 555           break;
 556
 557         case Bdup:
 558           {
 559             Lisp_Object v1;
 560             v1 = TOP;
 561             PUSH (v1);
 562             break;
 563           }
 564
 565         /* ------------------ */
 566
 567         case Bvarbind+6:
 568           op = FETCH;
 569           goto varbind;
 570
 571         case Bvarbind+7:
 572           op = FETCH2;
 573           goto varbind;
 574
 575         case Bvarbind:
 576         case Bvarbind+1:
 577         case Bvarbind+2:
 578         case Bvarbind+3:
 579         case Bvarbind+4:
 580         case Bvarbind+5:
 581           op -= Bvarbind;
 582         varbind:
 583           specbind (vectorp[op], POP);
 584           break;
 585
 586         case Bcall+6:
 587           op = FETCH;
 588           goto docall;
 589
 590         case Bcall+7:
 591           op = FETCH2;
 592           goto docall;
 593
 594         case Bcall:
 595         case Bcall+1:
 596         case Bcall+2:
 597         case Bcall+3:
 598         case Bcall+4:
 599         case Bcall+5:
 600           op -= Bcall;
 601         docall:
 602           {
 603             BEFORE_POTENTIAL_GC ();
 604             DISCARD (op);
 605 #ifdef BYTE_CODE_METER
 606             if (byte_metering_on && SYMBOLP (TOP))
 607               {
 608                 Lisp_Object v1, v2;
 609
 610                 v1 = TOP;
 611                 v2 = Fget (v1, Qbyte_code_meter);
 612                 if (INTEGERP (v2)
 613                     && XINT (v2) != ((1<<VALBITS)-1))
 614                   {
 615                     XSETINT (v2, XINT (v2) + 1);
 616                     Fput (v1, Qbyte_code_meter, v2);
 617                   }
 618               }
 619 #endif
 620             TOP = Ffuncall (op + 1, &TOP);
 621             AFTER_POTENTIAL_GC ();
 622             break;
 623           }
 624
 625         case Bunbind+6:
 626           op = FETCH;
 627           goto dounbind;
 628
 629         case Bunbind+7:
 630           op = FETCH2;
 631           goto dounbind;
 632
 633         case Bunbind:
 634         case Bunbind+1:
 635         case Bunbind+2:
 636         case Bunbind+3:
 637         case Bunbind+4:
 638         case Bunbind+5:
 639           op -= Bunbind;
 640         dounbind:
 641           BEFORE_POTENTIAL_GC ();
 642           unbind_to (specpdl_ptr - specpdl - op, Qnil);
 643           AFTER_POTENTIAL_GC ();
 644           break;
 645
 646         case Bunbind_all:
 647           /* To unbind back to the beginning of this frame.  Not used yet,
 648              but will be needed for tail-recursion elimination.  */
 649           BEFORE_POTENTIAL_GC ();
 650           unbind_to (count, Qnil);
 651           AFTER_POTENTIAL_GC ();
 652           break;
 653
 654         case Bgoto:
 655           MAYBE_GC ();
 656           QUIT;
 657           op = FETCH2;    /* pc = FETCH2 loses since FETCH2 contains pc++ */
 658           CHECK_RANGE (op);
 659           stack.pc = stack.byte_string_start + op;
 660           break;
 661
 662         case Bgotoifnonnil:
 663           MAYBE_GC ();
 664           op = FETCH2;
 665           if (!NILP (POP))
 666             {
 667               QUIT;
 668               CHECK_RANGE (op);
 669               stack.pc = stack.byte_string_start + op;
 670             }
 671           break;
 672
 673         case Bgotoifnilelsepop:
 674           MAYBE_GC ();
 675           op = FETCH2;
 676           if (NILP (TOP))
 677             {
 678               QUIT;
 679               CHECK_RANGE (op);
 680               stack.pc = stack.byte_string_start + op;
 681             }
 682           else DISCARD (1);
 683           break;
 684
 685         case Bgotoifnonnilelsepop:
 686           MAYBE_GC ();
 687           op = FETCH2;
 688           if (!NILP (TOP))
 689             {
 690               QUIT;
 691               CHECK_RANGE (op);
 692               stack.pc = stack.byte_string_start + op;
 693             }
 694           else DISCARD (1);
 695           break;
 696
 697         case BRgoto:
 698           MAYBE_GC ();
 699           QUIT;
 700           stack.pc += (int) *stack.pc - 127;
 701           break;
 702
 703         case BRgotoifnil:
 704           MAYBE_GC ();
 705           if (NILP (POP))
 706             {
 707               QUIT;
 708               stack.pc += (int) *stack.pc - 128;
 709             }
 710           stack.pc++;
 711           break;
 712
 713         case BRgotoifnonnil:
 714           MAYBE_GC ();
 715           if (!NILP (POP))
 716             {
 717               QUIT;
 718               stack.pc += (int) *stack.pc - 128;
 719             }
 720           stack.pc++;
 721           break;
 722
 723         case BRgotoifnilelsepop:
 724           MAYBE_GC ();
 725           op = *stack.pc++;
 726           if (NILP (TOP))
 727             {
 728               QUIT;
 729               stack.pc += op - 128;
 730             }
 731           else DISCARD (1);
 732           break;
 733
 734         case BRgotoifnonnilelsepop:
 735           MAYBE_GC ();
 736           op = *stack.pc++;
 737           if (!NILP (TOP))
 738             {
 739               QUIT;
 740               stack.pc += op - 128;
 741             }
 742           else DISCARD (1);
 743           break;
 744
 745         case Breturn:
 746           result = POP;
 747           goto exit;
 748
 749         case Bdiscard:
 750           DISCARD (1);
 751           break;
 752
 753         case Bconstant2:
 754           PUSH (vectorp[FETCH2]);
 755           break;
 756
 757         case Bsave_excursion:
 758           record_unwind_protect (save_excursion_restore,
 759                                  save_excursion_save ());
 760           break;
 761
 762         case Bsave_current_buffer:
 763         case Bsave_current_buffer_1:
 764           record_unwind_protect (set_buffer_if_live, Fcurrent_buffer ());
 765           break;
 766
 767         case Bsave_window_excursion:
 768           BEFORE_POTENTIAL_GC ();
 769           TOP = Fsave_window_excursion (TOP);
 770           AFTER_POTENTIAL_GC ();
 771           break;
 772
 773         case Bsave_restriction:
 774           record_unwind_protect (save_restriction_restore,
 775                                  save_restriction_save ());
 776           break;
 777
 778         case Bcatch:
 779           {
 780             Lisp_Object v1;
 781             v1 = POP;
 782             BEFORE_POTENTIAL_GC ();
 783             TOP = internal_catch (TOP, Feval, v1);
 784             AFTER_POTENTIAL_GC ();
 785             break;
 786           }
 787
 788         case Bunwind_protect:
 789           record_unwind_protect (0, POP);
 790           (specpdl_ptr - 1)->symbol = Qnil;
 791           break;
 792
 793         case Bcondition_case:
 794           {
 795             Lisp_Object v1;
 796             v1 = POP;
 797             v1 = Fcons (POP, v1);
 798             BEFORE_POTENTIAL_GC ();
 799             TOP = Fcondition_case (Fcons (TOP, v1));
 800             AFTER_POTENTIAL_GC ();
 801             break;
 802           }
 803
 804         case Btemp_output_buffer_setup:
 805           BEFORE_POTENTIAL_GC ();
 806           temp_output_buffer_setup (XSTRING (TOP)->data);
 807           AFTER_POTENTIAL_GC ();
 808           TOP = Vstandard_output;
 809           break;
 810
 811         case Btemp_output_buffer_show:
 812           {
 813             Lisp_Object v1;
 814             v1 = POP;
 815             BEFORE_POTENTIAL_GC ();
 816             temp_output_buffer_show (TOP);
 817             TOP = v1;
 818             /* pop binding of standard-output */
 819             unbind_to (specpdl_ptr - specpdl - 1, Qnil);
 820             AFTER_POTENTIAL_GC ();
 821             break;
 822           }
 823
 824         case Bnth:
 825           {
 826             Lisp_Object v1, v2;
 827             v1 = POP;
 828             v2 = TOP;
 829             CHECK_NUMBER (v2, 0);
 830             op = XINT (v2);
 831             immediate_quit = 1;
 832             while (--op >= 0)
 833               {
 834                 if (CONSP (v1))
 835                   v1 = XCDR (v1);
 836                 else if (!NILP (v1))
 837                   {
 838                     immediate_quit = 0;
 839                     v1 = wrong_type_argument (Qlistp, v1);
 840                     immediate_quit = 1;
 841                     op++;
 842                   }
 843               }
 844             immediate_quit = 0;
 845             if (CONSP (v1))
 846               TOP = XCAR (v1);
 847             else if (NILP (v1))
 848               TOP = Qnil;
 849             else
 850               Fcar (wrong_type_argument (Qlistp, v1));
 851             break;
 852           }
 853
 854         case Bsymbolp:
 855           TOP = SYMBOLP (TOP) ? Qt : Qnil;
 856           break;
 857
 858         case Bconsp:
 859           TOP = CONSP (TOP) ? Qt : Qnil;
 860           break;
 861
 862         case Bstringp:
 863           TOP = STRINGP (TOP) ? Qt : Qnil;
 864           break;
 865
 866         case Blistp:
 867           TOP = CONSP (TOP) || NILP (TOP) ? Qt : Qnil;
 868           break;
 869
 870         case Bnot:
 871           TOP = NILP (TOP) ? Qt : Qnil;
 872           break;
 873
 874         case Bcons:
 875           {
 876             Lisp_Object v1;
 877             v1 = POP;
 878             TOP = Fcons (TOP, v1);
 879             break;
 880           }
 881
 882         case Blist1:
 883           TOP = Fcons (TOP, Qnil);
 884           break;
 885
 886         case Blist2:
 887           {
 888             Lisp_Object v1;
 889             v1 = POP;
 890             TOP = Fcons (TOP, Fcons (v1, Qnil));
 891             break;
 892           }
 893
 894         case Blist3:
 895           DISCARD (2);
 896           TOP = Flist (3, &TOP);
 897           break;
 898
 899         case Blist4:
 900           DISCARD (3);
 901           TOP = Flist (4, &TOP);
 902           break;
 903
 904         case BlistN:
 905           op = FETCH;
 906           DISCARD (op - 1);
 907           TOP = Flist (op, &TOP);
 908           break;
 909
 910         case Blength:
 911           TOP = Flength (TOP);
 912           break;
 913
 914         case Baref:
 915           {
 916             Lisp_Object v1;
 917             v1 = POP;
 918             TOP = Faref (TOP, v1);
 919             break;
 920           }
 921
 922         case Baset:
 923           {
 924             Lisp_Object v1, v2;
 925             v2 = POP; v1 = POP;
 926             TOP = Faset (TOP, v1, v2);
 927             break;
 928           }
 929
 930         case Bsymbol_value:
 931           TOP = Fsymbol_value (TOP);
 932           break;
 933
 934         case Bsymbol_function:
 935           TOP = Fsymbol_function (TOP);
 936           break;
 937
 938         case Bset:
 939           {
 940             Lisp_Object v1;
 941             v1 = POP;
 942             TOP = Fset (TOP, v1);
 943             break;
 944           }
 945
 946         case Bfset:
 947           {
 948             Lisp_Object v1;
 949             v1 = POP;
 950             TOP = Ffset (TOP, v1);
 951             break;
 952           }
 953
 954         case Bget:
 955           {
 956             Lisp_Object v1;
 957             v1 = POP;
 958             TOP = Fget (TOP, v1);
 959             break;
 960           }
 961
 962         case Bsubstring:
 963           {
 964             Lisp_Object v1, v2;
 965             v2 = POP; v1 = POP;
 966             BEFORE_POTENTIAL_GC ();
 967             TOP = Fsubstring (TOP, v1, v2);
 968             AFTER_POTENTIAL_GC ();
 969             break;
 970           }
 971
 972         case Bconcat2:
 973           DISCARD (1);
 974           TOP = Fconcat (2, &TOP);
 975           break;
 976
 977         case Bconcat3:
 978           DISCARD (2);
 979           TOP = Fconcat (3, &TOP);
 980           break;
 981
 982         case Bconcat4:
 983           DISCARD (3);
 984           TOP = Fconcat (4, &TOP);
 985           break;
 986
 987         case BconcatN:
 988           op = FETCH;
 989           DISCARD (op - 1);
 990           TOP = Fconcat (op, &TOP);
 991           break;
 992
 993         case Bsub1:
 994           {
 995             Lisp_Object v1;
 996             v1 = TOP;
 997             if (INTEGERP (v1))
 998               {
 999                 XSETINT (v1, XINT (v1) - 1);
1000                 TOP = v1;
1001               }
1002             else
1003               TOP = Fsub1 (v1);
1004             break;
1005           }
1006
1007         case Badd1:
1008           {
1009             Lisp_Object v1;
1010             v1 = TOP;
1011             if (INTEGERP (v1))
1012               {
1013                 XSETINT (v1, XINT (v1) + 1);
1014                 TOP = v1;
1015               }
1016             else
1017               TOP = Fadd1 (v1);
1018             break;
1019           }
1020
1021         case Beqlsign:
1022           {
1023             Lisp_Object v1, v2;
1024             v2 = POP; v1 = TOP;
1025             CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v1, 0);
1026             CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v2, 0);
1027 #ifdef LISP_FLOAT_TYPE
1028             if (FLOATP (v1) || FLOATP (v2))
1029               {
1030                 double f1, f2;
1031
1032                 f1 = (FLOATP (v1) ? XFLOAT_DATA (v1) : XINT (v1));
1033                 f2 = (FLOATP (v2) ? XFLOAT_DATA (v2) : XINT (v2));
1034                 TOP = (f1 == f2 ? Qt : Qnil);
1035               }
1036             else
1037 #endif
1038               TOP = (XINT (v1) == XINT (v2) ? Qt : Qnil);
1039             break;
1040           }
1041
1042         case Bgtr:
1043           {
1044             Lisp_Object v1;
1045             v1 = POP;
1046             TOP = Fgtr (TOP, v1);
1047             break;
1048           }
1049
1050         case Blss:
1051           {
1052             Lisp_Object v1;
1053             v1 = POP;
1054             TOP = Flss (TOP, v1);
1055             break;
1056           }
1057
1058         case Bleq:
1059           {
1060             Lisp_Object v1;
1061             v1 = POP;
1062             TOP = Fleq (TOP, v1);
1063             break;
1064           }
1065
1066         case Bgeq:
1067           {
1068             Lisp_Object v1;
1069             v1 = POP;
1070             TOP = Fgeq (TOP, v1);
1071             break;
1072           }
1073
1074         case Bdiff:
1075           DISCARD (1);
1076           TOP = Fminus (2, &TOP);
1077           break;
1078
1079         case Bnegate:
1080           {
1081             Lisp_Object v1;
1082             v1 = TOP;
1083             if (INTEGERP (v1))
1084               {
1085                 XSETINT (v1, - XINT (v1));
1086                 TOP = v1;
1087               }
1088             else
1089               TOP = Fminus (1, &TOP);
1090             break;
1091           }
1092
1093         case Bplus:
1094           DISCARD (1);
1095           TOP = Fplus (2, &TOP);
1096           break;
1097
1098         case Bmax:
1099           DISCARD (1);
1100           TOP = Fmax (2, &TOP);
1101           break;
1102
1103         case Bmin:
1104           DISCARD (1);
1105           TOP = Fmin (2, &TOP);
1106           break;
1107
1108         case Bmult:
1109           DISCARD (1);
1110           TOP = Ftimes (2, &TOP);
1111           break;
1112
1113         case Bquo:
1114           DISCARD (1);
1115           TOP = Fquo (2, &TOP);
1116           break;
1117
1118         case Brem:
1119           {
1120             Lisp_Object v1;
1121             v1 = POP;
1122             TOP = Frem (TOP, v1);
1123             break;
1124           }
1125
1126         case Bpoint:
1127           {
1128             Lisp_Object v1;
1129             XSETFASTINT (v1, PT);
1130             PUSH (v1);
1131             break;
1132           }
1133
1134         case Bgoto_char:
1135           BEFORE_POTENTIAL_GC ();
1136           TOP = Fgoto_char (TOP);
1137           AFTER_POTENTIAL_GC ();
1138           break;
1139
1140         case Binsert:
1141           BEFORE_POTENTIAL_GC ();
1142           TOP = Finsert (1, &TOP);
1143           AFTER_POTENTIAL_GC ();
1144           break;
1145
1146         case BinsertN:
1147           op = FETCH;
1148           BEFORE_POTENTIAL_GC ();
1149           DISCARD (op - 1);
1150           TOP = Finsert (op, &TOP);
1151           AFTER_POTENTIAL_GC ();
1152           break;
1153
1154         case Bpoint_max:
1155           {
1156             Lisp_Object v1;
1157             XSETFASTINT (v1, ZV);
1158             PUSH (v1);
1159             break;
1160           }
1161
1162         case Bpoint_min:
1163           {
1164             Lisp_Object v1;
1165             XSETFASTINT (v1, BEGV);
1166             PUSH (v1);
1167             break;
1168           }
1169
1170         case Bchar_after:
1171           TOP = Fchar_after (TOP);
1172           break;
1173
1174         case Bfollowing_char:
1175           {
1176             Lisp_Object v1;
1177             v1 = Ffollowing_char ();
1178             PUSH (v1);
1179             break;
1180           }
1181
1182         case Bpreceding_char:
1183           {
1184             Lisp_Object v1;
1185             v1 = Fprevious_char ();
1186             PUSH (v1);
1187             break;
1188           }
1189
1190         case Bcurrent_column:
1191           {
1192             Lisp_Object v1;
1193             XSETFASTINT (v1, current_column ());
1194             PUSH (v1);
1195             break;
1196           }
1197
1198         case Bindent_to:
1199           BEFORE_POTENTIAL_GC ();
1200           TOP = Findent_to (TOP, Qnil);
1201           AFTER_POTENTIAL_GC ();
1202           break;
1203
1204         case Beolp:
1205           PUSH (Feolp ());
1206           break;
1207
1208         case Beobp:
1209           PUSH (Feobp ());
1210           break;
1211
1212         case Bbolp:
1213           PUSH (Fbolp ());
1214           break;
1215
1216         case Bbobp:
1217           PUSH (Fbobp ());
1218           break;
1219
1220         case Bcurrent_buffer:
1221           PUSH (Fcurrent_buffer ());
1222           break;
1223
1224         case Bset_buffer:
1225           BEFORE_POTENTIAL_GC ();
1226           TOP = Fset_buffer (TOP);
1227           AFTER_POTENTIAL_GC ();
1228           break;
1229
1230         case Binteractive_p:
1231           PUSH (Finteractive_p ());
1232           break;
1233
1234         case Bforward_char:
1235           BEFORE_POTENTIAL_GC ();
1236           TOP = Fforward_char (TOP);
1237           AFTER_POTENTIAL_GC ();
1238           break;
1239
1240         case Bforward_word:
1241           BEFORE_POTENTIAL_GC ();
1242           TOP = Fforward_word (TOP);
1243           AFTER_POTENTIAL_GC ();
1244           break;
1245
1246         case Bskip_chars_forward:
1247           {
1248             Lisp_Object v1;
1249             v1 = POP;
1250             BEFORE_POTENTIAL_GC ();
1251             TOP = Fskip_chars_forward (TOP, v1);
1252             AFTER_POTENTIAL_GC ();
1253             break;
1254           }
1255
1256         case Bskip_chars_backward:
1257           {
1258             Lisp_Object v1;
1259             v1 = POP;
1260             BEFORE_POTENTIAL_GC ();
1261             TOP = Fskip_chars_backward (TOP, v1);
1262             AFTER_POTENTIAL_GC ();
1263             break;
1264           }
1265
1266         case Bforward_line:
1267           BEFORE_POTENTIAL_GC ();
1268           TOP = Fforward_line (TOP);
1269           AFTER_POTENTIAL_GC ();
1270           break;
1271
1272         case Bchar_syntax:
1273           CHECK_NUMBER (TOP, 0);
1274           XSETFASTINT (TOP, syntax_code_spec[(int) SYNTAX (XINT (TOP))]);
1275           break;
1276
1277         case Bbuffer_substring:
1278           {
1279             Lisp_Object v1;
1280             v1 = POP;
1281             BEFORE_POTENTIAL_GC ();
1282             TOP = Fbuffer_substring (TOP, v1);
1283             AFTER_POTENTIAL_GC ();
1284             break;
1285           }
1286
1287         case Bdelete_region:
1288           {
1289             Lisp_Object v1;
1290             v1 = POP;
1291             BEFORE_POTENTIAL_GC ();
1292             TOP = Fdelete_region (TOP, v1);
1293             AFTER_POTENTIAL_GC ();
1294             break;
1295           }
1296
1297         case Bnarrow_to_region:
1298           {
1299             Lisp_Object v1;
1300             v1 = POP;
1301             BEFORE_POTENTIAL_GC ();
1302             TOP = Fnarrow_to_region (TOP, v1);
1303             AFTER_POTENTIAL_GC ();
1304             break;
1305           }
1306
1307         case Bwiden:
1308           BEFORE_POTENTIAL_GC ();
1309           PUSH (Fwiden ());
1310           AFTER_POTENTIAL_GC ();
1311           break;
1312
1313         case Bend_of_line:
1314           BEFORE_POTENTIAL_GC ();
1315           TOP = Fend_of_line (TOP);
1316           AFTER_POTENTIAL_GC ();
1317           break;
1318
1319         case Bset_marker:
1320           {
1321             Lisp_Object v1, v2;
1322             v1 = POP;
1323             v2 = POP;
1324             TOP = Fset_marker (TOP, v2, v1);
1325             break;
1326           }
1327
1328         case Bmatch_beginning:
1329           TOP = Fmatch_beginning (TOP);
1330           break;
1331
1332         case Bmatch_end:
1333           TOP = Fmatch_end (TOP);
1334           break;
1335
1336         case Bupcase:
1337           TOP = Fupcase (TOP);
1338           break;
1339
1340         case Bdowncase:
1341           TOP = Fdowncase (TOP);
1342         break;
1343
1344         case Bstringeqlsign:
1345           {
1346             Lisp_Object v1;
1347             v1 = POP;
1348             TOP = Fstring_equal (TOP, v1);
1349             break;
1350           }
1351
1352         case Bstringlss:
1353           {
1354             Lisp_Object v1;
1355             v1 = POP;
1356             TOP = Fstring_lessp (TOP, v1);
1357             break;
1358           }
1359
1360         case Bequal:
1361           {
1362             Lisp_Object v1;
1363             v1 = POP;
1364             TOP = Fequal (TOP, v1);
1365             break;
1366           }
1367
1368         case Bnthcdr:
1369           {
1370             Lisp_Object v1;
1371             v1 = POP;
1372             TOP = Fnthcdr (TOP, v1);
1373             break;
1374           }
1375
1376         case Belt:
1377           {
1378             Lisp_Object v1, v2;
1379             if (CONSP (TOP))
1380               {
1381                 /* Exchange args and then do nth.  */
1382                 v2 = POP;
1383                 v1 = TOP;
1384                 CHECK_NUMBER (v2, 0);
1385                 op = XINT (v2);
1386                 immediate_quit = 1;
1387                 while (--op >= 0)
1388                   {
1389                     if (CONSP (v1))
1390                       v1 = XCDR (v1);
1391                     else if (!NILP (v1))
1392                       {
1393                         immediate_quit = 0;
1394                         v1 = wrong_type_argument (Qlistp, v1);
1395                         immediate_quit = 1;
1396                         op++;
1397                       }
1398                   }
1399                 immediate_quit = 0;
1400                 if (CONSP (v1))
1401                   TOP = XCAR (v1);
1402                 else if (NILP (v1))
1403                   TOP = Qnil;
1404                 else
1405                   Fcar (wrong_type_argument (Qlistp, v1));
1406               }
1407             else
1408               {
1409                 v1 = POP;
1410                 TOP = Felt (TOP, v1);
1411               }
1412             break;
1413           }
1414
1415         case Bmember:
1416           {
1417             Lisp_Object v1;
1418             v1 = POP;
1419             TOP = Fmember (TOP, v1);
1420             break;
1421           }
1422
1423         case Bassq:
1424           {
1425             Lisp_Object v1;
1426             v1 = POP;
1427             TOP = Fassq (TOP, v1);
1428             break;
1429           }
1430
1431         case Bnreverse:
1432           TOP = Fnreverse (TOP);
1433           break;
1434
1435         case Bsetcar:
1436           {
1437             Lisp_Object v1;
1438             v1 = POP;
1439             TOP = Fsetcar (TOP, v1);
1440             break;
1441           }
1442
1443         case Bsetcdr:
1444           {
1445             Lisp_Object v1;
1446             v1 = POP;
1447             TOP = Fsetcdr (TOP, v1);
1448             break;
1449           }
1450
1451         case Bcar_safe:
1452           {
1453             Lisp_Object v1;
1454             v1 = TOP;
1455             if (CONSP (v1))
1456               TOP = XCAR (v1);
1457             else
1458               TOP = Qnil;
1459             break;
1460           }
1461
1462         case Bcdr_safe:
1463           {
1464             Lisp_Object v1;
1465             v1 = TOP;
1466             if (CONSP (v1))
1467               TOP = XCDR (v1);
1468             else
1469               TOP = Qnil;
1470             break;
1471           }
1472
1473         case Bnconc:
1474           DISCARD (1);
1475           TOP = Fnconc (2, &TOP);
1476           break;
1477
1478         case Bnumberp:
1479           TOP = (NUMBERP (TOP) ? Qt : Qnil);
1480           break;
1481
1482         case Bintegerp:
1483           TOP = INTEGERP (TOP) ? Qt : Qnil;
1484           break;
1485
1486 #ifdef BYTE_CODE_SAFE
1487         case Bset_mark:
1488           error ("set-mark is an obsolete bytecode");
1489           break;
1490         case Bscan_buffer:
1491           error ("scan-buffer is an obsolete bytecode");
1492           break;
1493 #endif
1494
1495         default:
1496 #ifdef BYTE_CODE_SAFE
1497           if (op < Bconstant)
1498             error ("unknown bytecode %d (byte compiler bug)", op);
1499           if ((op -= Bconstant) >= const_length)
1500             error ("no constant number %d (byte compiler bug)", op);
1501           PUSH (vectorp[op]);
1502 #else
1503           PUSH (vectorp[op - Bconstant]);
1504 #endif
1505         }
1506     }
1507
1508  exit:
1509
1510   byte_stack_list = byte_stack_list->next;
1511
1512   /* Binds and unbinds are supposed to be compiled balanced.  */
1513   if (specpdl_ptr - specpdl != count)
1514 #ifdef BYTE_CODE_SAFE
1515     error ("binding stack not balanced (serious byte compiler bug)");
1516 #else
1517     abort ();
1518 #endif
1519
1520   return result;
1521 }
1522
1523 void
1524 syms_of_bytecode ()
1525 {
1526   Qbytecode = intern ("byte-code");
1527   staticpro (&Qbytecode);
1528
1529   defsubr (&Sbyte_code);
1530
1531 #ifdef BYTE_CODE_METER
1532
1533   DEFVAR_LISP ("byte-code-meter", &Vbyte_code_meter,
1534    "A vector of vectors which holds a histogram of byte-code usage.\n\
1535 (aref (aref byte-code-meter 0) CODE) indicates how many times the byte\n\
1536 opcode CODE has been executed.\n\
1537 (aref (aref byte-code-meter CODE1) CODE2), where CODE1 is not 0,\n\
1538 indicates how many times the byte opcodes CODE1 and CODE2 have been\n\
1539 executed in succession.");
1540   DEFVAR_BOOL ("byte-metering-on", &byte_metering_on,
1541    "If non-nil, keep profiling information on byte code usage.\n\
1542 The variable byte-code-meter indicates how often each byte opcode is used.\n\
1543 If a symbol has a property named `byte-code-meter' whose value is an\n\
1544 integer, it is incremented each time that symbol's function is called.");
1545
1546   byte_metering_on = 0;
1547   Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
1548   Qbyte_code_meter = intern ("byte-code-meter");
1549   staticpro (&Qbyte_code_meter);
1550   {
1551     int i = 256;
1552     while (i--)
1553       XVECTOR (Vbyte_code_meter)->contents[i] =
1554         Fmake_vector (make_number (256), make_number (0));
1555   }
1556 #endif
1557 }