src/bytecode.c

   1 /* Execution of byte code produced by bytecomp.el.
   2    Copyright (C) 1985-1988, 1993, 2000-2017 Free Software Foundation,
   3    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 3 of the License, or (at
  10 your option) 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.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <config.h>
  21
  22 #include "lisp.h"
  23 #include "blockinput.h"
  24 #include "character.h"
  25 #include "buffer.h"
  26 #include "keyboard.h"
  27 #include "syntax.h"
  28 #include "window.h"
  29
  30 /* Work around GCC bug 54561.  */
  31 #if GNUC_PREREQ (4, 3, 0)
  32 # pragma GCC diagnostic ignored "-Wclobbered"
  33 #endif
  34
  35 /* Define BYTE_CODE_SAFE true to enable some minor sanity checking,
  36    useful for debugging the byte compiler.  It defaults to false.  */
  37
  38 #ifndef BYTE_CODE_SAFE
  39 # define BYTE_CODE_SAFE false
  40 #endif
  41
  42 /* Define BYTE_CODE_METER to generate a byte-op usage histogram.  */
  43 /* #define BYTE_CODE_METER */
  44
  45 /* If BYTE_CODE_THREADED is defined, then the interpreter will be
  46    indirect threaded, using GCC's computed goto extension.  This code,
  47    as currently implemented, is incompatible with BYTE_CODE_SAFE and
  48    BYTE_CODE_METER.  */
  49 #if (defined __GNUC__ && !defined __STRICT_ANSI__ && !defined __CHKP__ \
  50      && !BYTE_CODE_SAFE && !defined BYTE_CODE_METER)
  51 #define BYTE_CODE_THREADED
  52 #endif
  53
  54 \f
  55 #ifdef BYTE_CODE_METER
  56
  57 #define METER_2(code1, code2) \
  58   (*aref_addr (AREF (Vbyte_code_meter, code1), code2))
  59 #define METER_1(code) METER_2 (0, code)
  60
  61 #define METER_CODE(last_code, this_code)                                \
  62 {                                                                       \
  63   if (byte_metering_on)                                                 \
  64     {                                                                   \
  65       if (XFASTINT (METER_1 (this_code)) < MOST_POSITIVE_FIXNUM)        \
  66         XSETFASTINT (METER_1 (this_code),                               \
  67                      XFASTINT (METER_1 (this_code)) + 1);               \
  68       if (last_code                                                     \
  69           && (XFASTINT (METER_2 (last_code, this_code))                 \
  70               < MOST_POSITIVE_FIXNUM))                                  \
  71         XSETFASTINT (METER_2 (last_code, this_code),                    \
  72                      XFASTINT (METER_2 (last_code, this_code)) + 1);    \
  73     }                                                                   \
  74 }
  75
  76 #endif /* BYTE_CODE_METER */
  77 \f
  78
  79 /*  Byte codes: */
  80
  81 #define BYTE_CODES                                                      \
  82 DEFINE (Bstack_ref, 0) /* Actually, Bstack_ref+0 is not implemented: use dup.  */ \
  83 DEFINE (Bstack_ref1, 1)                                                 \
  84 DEFINE (Bstack_ref2, 2)                                                 \
  85 DEFINE (Bstack_ref3, 3)                                                 \
  86 DEFINE (Bstack_ref4, 4)                                                 \
  87 DEFINE (Bstack_ref5, 5)                                                 \
  88 DEFINE (Bstack_ref6, 6)                                                 \
  89 DEFINE (Bstack_ref7, 7)                                                 \
  90 DEFINE (Bvarref, 010)                                                   \
  91 DEFINE (Bvarref1, 011)                                                  \
  92 DEFINE (Bvarref2, 012)                                                  \
  93 DEFINE (Bvarref3, 013)                                                  \
  94 DEFINE (Bvarref4, 014)                                                  \
  95 DEFINE (Bvarref5, 015)                                                  \
  96 DEFINE (Bvarref6, 016)                                                  \
  97 DEFINE (Bvarref7, 017)                                                  \
  98 DEFINE (Bvarset, 020)                                                   \
  99 DEFINE (Bvarset1, 021)                                                  \
 100 DEFINE (Bvarset2, 022)                                                  \
 101 DEFINE (Bvarset3, 023)                                                  \
 102 DEFINE (Bvarset4, 024)                                                  \
 103 DEFINE (Bvarset5, 025)                                                  \
 104 DEFINE (Bvarset6, 026)                                                  \
 105 DEFINE (Bvarset7, 027)                                                  \
 106 DEFINE (Bvarbind, 030)                                                  \
 107 DEFINE (Bvarbind1, 031)                                                 \
 108 DEFINE (Bvarbind2, 032)                                                 \
 109 DEFINE (Bvarbind3, 033)                                                 \
 110 DEFINE (Bvarbind4, 034)                                                 \
 111 DEFINE (Bvarbind5, 035)                                                 \
 112 DEFINE (Bvarbind6, 036)                                                 \
 113 DEFINE (Bvarbind7, 037)                                                 \
 114 DEFINE (Bcall, 040)                                                     \
 115 DEFINE (Bcall1, 041)                                                    \
 116 DEFINE (Bcall2, 042)                                                    \
 117 DEFINE (Bcall3, 043)                                                    \
 118 DEFINE (Bcall4, 044)                                                    \
 119 DEFINE (Bcall5, 045)                                                    \
 120 DEFINE (Bcall6, 046)                                                    \
 121 DEFINE (Bcall7, 047)                                                    \
 122 DEFINE (Bunbind, 050)                                                   \
 123 DEFINE (Bunbind1, 051)                                                  \
 124 DEFINE (Bunbind2, 052)                                                  \
 125 DEFINE (Bunbind3, 053)                                                  \
 126 DEFINE (Bunbind4, 054)                                                  \
 127 DEFINE (Bunbind5, 055)                                                  \
 128 DEFINE (Bunbind6, 056)                                                  \
 129 DEFINE (Bunbind7, 057)                                                  \
 130                                                                         \
 131 DEFINE (Bpophandler, 060)                                               \
 132 DEFINE (Bpushconditioncase, 061)                                        \
 133 DEFINE (Bpushcatch, 062)                                                \
 134                                                                         \
 135 DEFINE (Bnth, 070)                                                      \
 136 DEFINE (Bsymbolp, 071)                                                  \
 137 DEFINE (Bconsp, 072)                                                    \
 138 DEFINE (Bstringp, 073)                                                  \
 139 DEFINE (Blistp, 074)                                                    \
 140 DEFINE (Beq, 075)                                                       \
 141 DEFINE (Bmemq, 076)                                                     \
 142 DEFINE (Bnot, 077)                                                      \
 143 DEFINE (Bcar, 0100)                                                     \
 144 DEFINE (Bcdr, 0101)                                                     \
 145 DEFINE (Bcons, 0102)                                                    \
 146 DEFINE (Blist1, 0103)                                                   \
 147 DEFINE (Blist2, 0104)                                                   \
 148 DEFINE (Blist3, 0105)                                                   \
 149 DEFINE (Blist4, 0106)                                                   \
 150 DEFINE (Blength, 0107)                                                  \
 151 DEFINE (Baref, 0110)                                                    \
 152 DEFINE (Baset, 0111)                                                    \
 153 DEFINE (Bsymbol_value, 0112)                                            \
 154 DEFINE (Bsymbol_function, 0113)                                         \
 155 DEFINE (Bset, 0114)                                                     \
 156 DEFINE (Bfset, 0115)                                                    \
 157 DEFINE (Bget, 0116)                                                     \
 158 DEFINE (Bsubstring, 0117)                                               \
 159 DEFINE (Bconcat2, 0120)                                                 \
 160 DEFINE (Bconcat3, 0121)                                                 \
 161 DEFINE (Bconcat4, 0122)                                                 \
 162 DEFINE (Bsub1, 0123)                                                    \
 163 DEFINE (Badd1, 0124)                                                    \
 164 DEFINE (Beqlsign, 0125)                                                 \
 165 DEFINE (Bgtr, 0126)                                                     \
 166 DEFINE (Blss, 0127)                                                     \
 167 DEFINE (Bleq, 0130)                                                     \
 168 DEFINE (Bgeq, 0131)                                                     \
 169 DEFINE (Bdiff, 0132)                                                    \
 170 DEFINE (Bnegate, 0133)                                                  \
 171 DEFINE (Bplus, 0134)                                                    \
 172 DEFINE (Bmax, 0135)                                                     \
 173 DEFINE (Bmin, 0136)                                                     \
 174 DEFINE (Bmult, 0137)                                                    \
 175                                                                         \
 176 DEFINE (Bpoint, 0140)                                                   \
 177 /* Was Bmark in v17.  */                                                \
 178 DEFINE (Bsave_current_buffer, 0141) /* Obsolete.  */                    \
 179 DEFINE (Bgoto_char, 0142)                                               \
 180 DEFINE (Binsert, 0143)                                                  \
 181 DEFINE (Bpoint_max, 0144)                                               \
 182 DEFINE (Bpoint_min, 0145)                                               \
 183 DEFINE (Bchar_after, 0146)                                              \
 184 DEFINE (Bfollowing_char, 0147)                                          \
 185 DEFINE (Bpreceding_char, 0150)                                          \
 186 DEFINE (Bcurrent_column, 0151)                                          \
 187 DEFINE (Bindent_to, 0152)                                               \
 188 DEFINE (Beolp, 0154)                                                    \
 189 DEFINE (Beobp, 0155)                                                    \
 190 DEFINE (Bbolp, 0156)                                                    \
 191 DEFINE (Bbobp, 0157)                                                    \
 192 DEFINE (Bcurrent_buffer, 0160)                                          \
 193 DEFINE (Bset_buffer, 0161)                                              \
 194 DEFINE (Bsave_current_buffer_1, 0162) /* Replacing Bsave_current_buffer.  */ \
 195 DEFINE (Binteractive_p, 0164) /* Obsolete since Emacs-24.1.  */         \
 196                                                                         \
 197 DEFINE (Bforward_char, 0165)                                            \
 198 DEFINE (Bforward_word, 0166)                                            \
 199 DEFINE (Bskip_chars_forward, 0167)                                      \
 200 DEFINE (Bskip_chars_backward, 0170)                                     \
 201 DEFINE (Bforward_line, 0171)                                            \
 202 DEFINE (Bchar_syntax, 0172)                                             \
 203 DEFINE (Bbuffer_substring, 0173)                                        \
 204 DEFINE (Bdelete_region, 0174)                                           \
 205 DEFINE (Bnarrow_to_region, 0175)                                        \
 206 DEFINE (Bwiden, 0176)                                                   \
 207 DEFINE (Bend_of_line, 0177)                                             \
 208                                                                         \
 209 DEFINE (Bconstant2, 0201)                                               \
 210 DEFINE (Bgoto, 0202)                                                    \
 211 DEFINE (Bgotoifnil, 0203)                                               \
 212 DEFINE (Bgotoifnonnil, 0204)                                            \
 213 DEFINE (Bgotoifnilelsepop, 0205)                                        \
 214 DEFINE (Bgotoifnonnilelsepop, 0206)                                     \
 215 DEFINE (Breturn, 0207)                                                  \
 216 DEFINE (Bdiscard, 0210)                                                 \
 217 DEFINE (Bdup, 0211)                                                     \
 218                                                                         \
 219 DEFINE (Bsave_excursion, 0212)                                          \
 220 DEFINE (Bsave_window_excursion, 0213) /* Obsolete since Emacs-24.1.  */ \
 221 DEFINE (Bsave_restriction, 0214)                                        \
 222 DEFINE (Bcatch, 0215)                                                   \
 223                                                                         \
 224 DEFINE (Bunwind_protect, 0216)                                          \
 225 DEFINE (Bcondition_case, 0217)                                          \
 226 DEFINE (Btemp_output_buffer_setup, 0220) /* Obsolete since Emacs-24.1.  */ \
 227 DEFINE (Btemp_output_buffer_show, 0221)  /* Obsolete since Emacs-24.1.  */ \
 228                                                                         \
 229 DEFINE (Bunbind_all, 0222)      /* Obsolete.  Never used.  */           \
 230                                                                         \
 231 DEFINE (Bset_marker, 0223)                                              \
 232 DEFINE (Bmatch_beginning, 0224)                                         \
 233 DEFINE (Bmatch_end, 0225)                                               \
 234 DEFINE (Bupcase, 0226)                                                  \
 235 DEFINE (Bdowncase, 0227)                                                \
 236                                                                         \
 237 DEFINE (Bstringeqlsign, 0230)                                           \
 238 DEFINE (Bstringlss, 0231)                                               \
 239 DEFINE (Bequal, 0232)                                                   \
 240 DEFINE (Bnthcdr, 0233)                                                  \
 241 DEFINE (Belt, 0234)                                                     \
 242 DEFINE (Bmember, 0235)                                                  \
 243 DEFINE (Bassq, 0236)                                                    \
 244 DEFINE (Bnreverse, 0237)                                                \
 245 DEFINE (Bsetcar, 0240)                                                  \
 246 DEFINE (Bsetcdr, 0241)                                                  \
 247 DEFINE (Bcar_safe, 0242)                                                \
 248 DEFINE (Bcdr_safe, 0243)                                                \
 249 DEFINE (Bnconc, 0244)                                                   \
 250 DEFINE (Bquo, 0245)                                                     \
 251 DEFINE (Brem, 0246)                                                     \
 252 DEFINE (Bnumberp, 0247)                                                 \
 253 DEFINE (Bintegerp, 0250)                                                \
 254                                                                         \
 255 DEFINE (BRgoto, 0252)                                                   \
 256 DEFINE (BRgotoifnil, 0253)                                              \
 257 DEFINE (BRgotoifnonnil, 0254)                                           \
 258 DEFINE (BRgotoifnilelsepop, 0255)                                       \
 259 DEFINE (BRgotoifnonnilelsepop, 0256)                                    \
 260                                                                         \
 261 DEFINE (BlistN, 0257)                                                   \
 262 DEFINE (BconcatN, 0260)                                                 \
 263 DEFINE (BinsertN, 0261)                                                 \
 264                                                                         \
 265 /* Bstack_ref is code 0.  */                                            \
 266 DEFINE (Bstack_set,  0262)                                              \
 267 DEFINE (Bstack_set2, 0263)                                              \
 268 DEFINE (BdiscardN,   0266)                                              \
 269                                                                         \
 270 DEFINE (Bswitch, 0267)                                                  \
 271                                                                         \
 272 DEFINE (Bconstant, 0300)
 273
 274 enum byte_code_op
 275 {
 276 #define DEFINE(name, value) name = value,
 277     BYTE_CODES
 278 #undef DEFINE
 279
 280 #if BYTE_CODE_SAFE
 281     Bscan_buffer = 0153, /* No longer generated as of v18.  */
 282     Bset_mark = 0163, /* this loser is no longer generated as of v18 */
 283 #endif
 284 };
 285 \f
 286 /* Fetch the next byte from the bytecode stream.  */
 287
 288 #define FETCH (*pc++)
 289
 290 /* Fetch two bytes from the bytecode stream and make a 16-bit number
 291    out of them.  */
 292
 293 #define FETCH2 (op = FETCH, op + (FETCH << 8))
 294
 295 /* Push X onto the execution stack.  The expression X should not
 296    contain TOP, to avoid competing side effects.  */
 297
 298 #define PUSH(x) (*++top = (x))
 299
 300 /* Pop a value off the execution stack.  */
 301
 302 #define POP (*top--)
 303
 304 /* Discard n values from the execution stack.  */
 305
 306 #define DISCARD(n) (top -= (n))
 307
 308 /* Get the value which is at the top of the execution stack, but don't
 309    pop it.  */
 310
 311 #define TOP (*top)
 312
 313 DEFUN ("byte-code", Fbyte_code, Sbyte_code, 3, 3, 0,
 314        doc: /* Function used internally in byte-compiled code.
 315 The first argument, BYTESTR, is a string of byte code;
 316 the second, VECTOR, a vector of constants;
 317 the third, MAXDEPTH, the maximum stack depth used in this function.
 318 If the third argument is incorrect, Emacs may crash.  */)
 319   (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth)
 320 {
 321   return exec_byte_code (bytestr, vector, maxdepth, Qnil, 0, NULL);
 322 }
 323
 324 static void
 325 bcall0 (Lisp_Object f)
 326 {
 327   Ffuncall (1, &f);
 328 }
 329
 330 /* Execute the byte-code in BYTESTR.  VECTOR is the constant vector, and
 331    MAXDEPTH is the maximum stack depth used (if MAXDEPTH is incorrect,
 332    emacs may crash!).  If ARGS_TEMPLATE is non-nil, it should be a lisp
 333    argument list (including &rest, &optional, etc.), and ARGS, of size
 334    NARGS, should be a vector of the actual arguments.  The arguments in
 335    ARGS are pushed on the stack according to ARGS_TEMPLATE before
 336    executing BYTESTR.  */
 337
 338 Lisp_Object
 339 exec_byte_code (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth,
 340                 Lisp_Object args_template, ptrdiff_t nargs, Lisp_Object *args)
 341 {
 342 #ifdef BYTE_CODE_METER
 343   int volatile this_op = 0;
 344 #endif
 345
 346   CHECK_STRING (bytestr);
 347   CHECK_VECTOR (vector);
 348   CHECK_NATNUM (maxdepth);
 349
 350   ptrdiff_t const_length = ASIZE (vector);
 351
 352   if (STRING_MULTIBYTE (bytestr))
 353     /* BYTESTR must have been produced by Emacs 20.2 or the earlier
 354        because they produced a raw 8-bit string for byte-code and now
 355        such a byte-code string is loaded as multibyte while raw 8-bit
 356        characters converted to multibyte form.  Thus, now we must
 357        convert them back to the originally intended unibyte form.  */
 358     bytestr = Fstring_as_unibyte (bytestr);
 359
 360   ptrdiff_t bytestr_length = SBYTES (bytestr);
 361   Lisp_Object *vectorp = XVECTOR (vector)->contents;
 362
 363   unsigned char quitcounter = 1;
 364   EMACS_INT stack_items = XFASTINT (maxdepth) + 1;
 365   USE_SAFE_ALLOCA;
 366   Lisp_Object *stack_base;
 367   SAFE_ALLOCA_LISP_EXTRA (stack_base, stack_items, bytestr_length);
 368   Lisp_Object *stack_lim = stack_base + stack_items;
 369   Lisp_Object *top = stack_base;
 370   memcpy (stack_lim, SDATA (bytestr), bytestr_length);
 371   void *void_stack_lim = stack_lim;
 372   unsigned char const *bytestr_data = void_stack_lim;
 373   unsigned char const *pc = bytestr_data;
 374   ptrdiff_t count = SPECPDL_INDEX ();
 375
 376   if (!NILP (args_template))
 377     {
 378       eassert (INTEGERP (args_template));
 379       ptrdiff_t at = XINT (args_template);
 380       bool rest = (at & 128) != 0;
 381       int mandatory = at & 127;
 382       ptrdiff_t nonrest = at >> 8;
 383       ptrdiff_t maxargs = rest ? PTRDIFF_MAX : nonrest;
 384       if (! (mandatory <= nargs && nargs <= maxargs))
 385         Fsignal (Qwrong_number_of_arguments,
 386                  list2 (Fcons (make_number (mandatory), make_number (nonrest)),
 387                         make_number (nargs)));
 388       ptrdiff_t pushedargs = min (nonrest, nargs);
 389       for (ptrdiff_t i = 0; i < pushedargs; i++, args++)
 390         PUSH (*args);
 391       if (nonrest < nargs)
 392         PUSH (Flist (nargs - nonrest, args));
 393       else
 394         for (ptrdiff_t i = nargs - rest; i < nonrest; i++)
 395           PUSH (Qnil);
 396     }
 397
 398   while (true)
 399     {
 400       int op;
 401       enum handlertype type;
 402
 403       if (BYTE_CODE_SAFE && ! (stack_base <= top && top < stack_lim))
 404         emacs_abort ();
 405
 406 #ifdef BYTE_CODE_METER
 407       int prev_op = this_op;
 408       this_op = op = FETCH;
 409       METER_CODE (prev_op, op);
 410 #elif !defined BYTE_CODE_THREADED
 411       op = FETCH;
 412 #endif
 413
 414       /* The interpreter can be compiled one of two ways: as an
 415          ordinary switch-based interpreter, or as a threaded
 416          interpreter.  The threaded interpreter relies on GCC's
 417          computed goto extension, so it is not available everywhere.
 418          Threading provides a performance boost.  These macros are how
 419          we allow the code to be compiled both ways.  */
 420 #ifdef BYTE_CODE_THREADED
 421       /* The CASE macro introduces an instruction's body.  It is
 422          either a label or a case label.  */
 423 #define CASE(OP) insn_ ## OP
 424       /* NEXT is invoked at the end of an instruction to go to the
 425          next instruction.  It is either a computed goto, or a
 426          plain break.  */
 427 #define NEXT goto *(targets[op = FETCH])
 428       /* FIRST is like NEXT, but is only used at the start of the
 429          interpreter body.  In the switch-based interpreter it is the
 430          switch, so the threaded definition must include a semicolon.  */
 431 #define FIRST NEXT;
 432       /* Most cases are labeled with the CASE macro, above.
 433          CASE_DEFAULT is one exception; it is used if the interpreter
 434          being built requires a default case.  The threaded
 435          interpreter does not, because the dispatch table is
 436          completely filled.  */
 437 #define CASE_DEFAULT
 438       /* This introduces an instruction that is known to call abort.  */
 439 #define CASE_ABORT CASE (Bstack_ref): CASE (default)
 440 #else
 441       /* See above for the meaning of the various defines.  */
 442 #define CASE(OP) case OP
 443 #define NEXT break
 444 #define FIRST switch (op)
 445 #define CASE_DEFAULT case 255: default:
 446 #define CASE_ABORT case 0
 447 #endif
 448
 449 #ifdef BYTE_CODE_THREADED
 450
 451       /* A convenience define that saves us a lot of typing and makes
 452          the table clearer.  */
 453 #define LABEL(OP) [OP] = &&insn_ ## OP
 454
 455       /* This is the dispatch table for the threaded interpreter.  */
 456       static const void *const targets[256] =
 457         {
 458           [0 ... (Bconstant - 1)] = &&insn_default,
 459           [Bconstant ... 255] = &&insn_Bconstant,
 460
 461 #define DEFINE(name, value) LABEL (name) ,
 462           BYTE_CODES
 463 #undef DEFINE
 464         };
 465
 466 #endif
 467
 468
 469       FIRST
 470         {
 471         CASE (Bvarref7):
 472           op = FETCH2;
 473           goto varref;
 474
 475         CASE (Bvarref):
 476         CASE (Bvarref1):
 477         CASE (Bvarref2):
 478         CASE (Bvarref3):
 479         CASE (Bvarref4):
 480         CASE (Bvarref5):
 481           op -= Bvarref;
 482           goto varref;
 483
 484         /* This seems to be the most frequently executed byte-code
 485            among the Bvarref's, so avoid a goto here.  */
 486         CASE (Bvarref6):
 487           op = FETCH;
 488         varref:
 489           {
 490             Lisp_Object v1 = vectorp[op], v2;
 491             if (!SYMBOLP (v1)
 492                 || XSYMBOL (v1)->redirect != SYMBOL_PLAINVAL
 493                 || (v2 = SYMBOL_VAL (XSYMBOL (v1)), EQ (v2, Qunbound)))
 494               v2 = Fsymbol_value (v1);
 495             PUSH (v2);
 496             NEXT;
 497           }
 498
 499         CASE (Bgotoifnil):
 500           {
 501             Lisp_Object v1 = POP;
 502             op = FETCH2;
 503             if (NILP (v1))
 504               goto op_branch;
 505             NEXT;
 506           }
 507
 508         CASE (Bcar):
 509           if (CONSP (TOP))
 510             TOP = XCAR (TOP);
 511           else if (!NILP (TOP))
 512             wrong_type_argument (Qlistp, TOP);
 513           NEXT;
 514
 515         CASE (Beq):
 516           {
 517             Lisp_Object v1 = POP;
 518             TOP = EQ (v1, TOP) ? Qt : Qnil;
 519             NEXT;
 520           }
 521
 522         CASE (Bmemq):
 523           {
 524             Lisp_Object v1 = POP;
 525             TOP = Fmemq (TOP, v1);
 526             NEXT;
 527           }
 528
 529         CASE (Bcdr):
 530           {
 531             if (CONSP (TOP))
 532               TOP = XCDR (TOP);
 533             else if (!NILP (TOP))
 534               wrong_type_argument (Qlistp, TOP);
 535             NEXT;
 536           }
 537
 538         CASE (Bvarset):
 539         CASE (Bvarset1):
 540         CASE (Bvarset2):
 541         CASE (Bvarset3):
 542         CASE (Bvarset4):
 543         CASE (Bvarset5):
 544           op -= Bvarset;
 545           goto varset;
 546
 547         CASE (Bvarset7):
 548           op = FETCH2;
 549           goto varset;
 550
 551         CASE (Bvarset6):
 552           op = FETCH;
 553         varset:
 554           {
 555             Lisp_Object sym = vectorp[op];
 556             Lisp_Object val = POP;
 557
 558             /* Inline the most common case.  */
 559             if (SYMBOLP (sym)
 560                 && !EQ (val, Qunbound)
 561                 && !XSYMBOL (sym)->redirect
 562                 && !SYMBOL_TRAPPED_WRITE_P (sym))
 563               SET_SYMBOL_VAL (XSYMBOL (sym), val);
 564             else
 565               set_internal (sym, val, Qnil, SET_INTERNAL_SET);
 566           }
 567           NEXT;
 568
 569         CASE (Bdup):
 570           {
 571             Lisp_Object v1 = TOP;
 572             PUSH (v1);
 573             NEXT;
 574           }
 575
 576         /* ------------------ */
 577
 578         CASE (Bvarbind6):
 579           op = FETCH;
 580           goto varbind;
 581
 582         CASE (Bvarbind7):
 583           op = FETCH2;
 584           goto varbind;
 585
 586         CASE (Bvarbind):
 587         CASE (Bvarbind1):
 588         CASE (Bvarbind2):
 589         CASE (Bvarbind3):
 590         CASE (Bvarbind4):
 591         CASE (Bvarbind5):
 592           op -= Bvarbind;
 593         varbind:
 594           /* Specbind can signal and thus GC.  */
 595           specbind (vectorp[op], POP);
 596           NEXT;
 597
 598         CASE (Bcall6):
 599           op = FETCH;
 600           goto docall;
 601
 602         CASE (Bcall7):
 603           op = FETCH2;
 604           goto docall;
 605
 606         CASE (Bcall):
 607         CASE (Bcall1):
 608         CASE (Bcall2):
 609         CASE (Bcall3):
 610         CASE (Bcall4):
 611         CASE (Bcall5):
 612           op -= Bcall;
 613         docall:
 614           {
 615             DISCARD (op);
 616 #ifdef BYTE_CODE_METER
 617             if (byte_metering_on && SYMBOLP (TOP))
 618               {
 619                 Lisp_Object v1 = TOP;
 620                 Lisp_Object v2 = Fget (v1, Qbyte_code_meter);
 621                 if (INTEGERP (v2)
 622                     && XINT (v2) < MOST_POSITIVE_FIXNUM)
 623                   {
 624                     XSETINT (v2, XINT (v2) + 1);
 625                     Fput (v1, Qbyte_code_meter, v2);
 626                   }
 627               }
 628 #endif
 629             TOP = Ffuncall (op + 1, &TOP);
 630             NEXT;
 631           }
 632
 633         CASE (Bunbind6):
 634           op = FETCH;
 635           goto dounbind;
 636
 637         CASE (Bunbind7):
 638           op = FETCH2;
 639           goto dounbind;
 640
 641         CASE (Bunbind):
 642         CASE (Bunbind1):
 643         CASE (Bunbind2):
 644         CASE (Bunbind3):
 645         CASE (Bunbind4):
 646         CASE (Bunbind5):
 647           op -= Bunbind;
 648         dounbind:
 649           unbind_to (SPECPDL_INDEX () - op, Qnil);
 650           NEXT;
 651
 652         CASE (Bunbind_all):     /* Obsolete.  Never used.  */
 653           /* To unbind back to the beginning of this frame.  Not used yet,
 654              but will be needed for tail-recursion elimination.  */
 655           unbind_to (count, Qnil);
 656           NEXT;
 657
 658         CASE (Bgoto):
 659           op = FETCH2;
 660         op_branch:
 661           op -= pc - bytestr_data;
 662         op_relative_branch:
 663           if (BYTE_CODE_SAFE
 664               && ! (bytestr_data - pc <= op
 665                     && op < bytestr_data + bytestr_length - pc))
 666             emacs_abort ();
 667           quitcounter += op < 0;
 668           if (!quitcounter)
 669             {
 670               quitcounter = 1;
 671               maybe_gc ();
 672               maybe_quit ();
 673             }
 674           pc += op;
 675           NEXT;
 676
 677         CASE (Bgotoifnonnil):
 678           op = FETCH2;
 679           if (!NILP (POP))
 680             goto op_branch;
 681           NEXT;
 682
 683         CASE (Bgotoifnilelsepop):
 684           op = FETCH2;
 685           if (NILP (TOP))
 686             goto op_branch;
 687           DISCARD (1);
 688           NEXT;
 689
 690         CASE (Bgotoifnonnilelsepop):
 691           op = FETCH2;
 692           if (!NILP (TOP))
 693             goto op_branch;
 694           DISCARD (1);
 695           NEXT;
 696
 697         CASE (BRgoto):
 698           op = FETCH - 128;
 699           goto op_relative_branch;
 700
 701         CASE (BRgotoifnil):
 702           op = FETCH - 128;
 703           if (NILP (POP))
 704             goto op_relative_branch;
 705           NEXT;
 706
 707         CASE (BRgotoifnonnil):
 708           op = FETCH - 128;
 709           if (!NILP (POP))
 710             goto op_relative_branch;
 711           NEXT;
 712
 713         CASE (BRgotoifnilelsepop):
 714           op = FETCH - 128;
 715           if (NILP (TOP))
 716             goto op_relative_branch;
 717           DISCARD (1);
 718           NEXT;
 719
 720         CASE (BRgotoifnonnilelsepop):
 721           op = FETCH - 128;
 722           if (!NILP (TOP))
 723             goto op_relative_branch;
 724           DISCARD (1);
 725           NEXT;
 726
 727         CASE (Breturn):
 728           goto exit;
 729
 730         CASE (Bdiscard):
 731           DISCARD (1);
 732           NEXT;
 733
 734         CASE (Bconstant2):
 735           PUSH (vectorp[FETCH2]);
 736           NEXT;
 737
 738         CASE (Bsave_excursion):
 739           record_unwind_protect (save_excursion_restore,
 740                                  save_excursion_save ());
 741           NEXT;
 742
 743         CASE (Bsave_current_buffer): /* Obsolete since ??.  */
 744         CASE (Bsave_current_buffer_1):
 745           record_unwind_current_buffer ();
 746           NEXT;
 747
 748         CASE (Bsave_window_excursion): /* Obsolete since 24.1.  */
 749           {
 750             ptrdiff_t count1 = SPECPDL_INDEX ();
 751             record_unwind_protect (restore_window_configuration,
 752                                    Fcurrent_window_configuration (Qnil));
 753             TOP = Fprogn (TOP);
 754             unbind_to (count1, TOP);
 755             NEXT;
 756           }
 757
 758         CASE (Bsave_restriction):
 759           record_unwind_protect (save_restriction_restore,
 760                                  save_restriction_save ());
 761           NEXT;
 762
 763         CASE (Bcatch):          /* Obsolete since 24.4.  */
 764           {
 765             Lisp_Object v1 = POP;
 766             TOP = internal_catch (TOP, eval_sub, v1);
 767             NEXT;
 768           }
 769
 770         CASE (Bpushcatch):      /* New in 24.4.  */
 771           type = CATCHER;
 772           goto pushhandler;
 773         CASE (Bpushconditioncase): /* New in 24.4.  */
 774           type = CONDITION_CASE;
 775         pushhandler:
 776           {
 777             struct handler *c = push_handler (POP, type);
 778             c->bytecode_dest = FETCH2;
 779             c->bytecode_top = top;
 780
 781             if (sys_setjmp (c->jmp))
 782               {
 783                 struct handler *c = handlerlist;
 784                 top = c->bytecode_top;
 785                 op = c->bytecode_dest;
 786                 handlerlist = c->next;
 787                 PUSH (c->val);
 788                 goto op_branch;
 789               }
 790
 791             NEXT;
 792           }
 793
 794         CASE (Bpophandler):     /* New in 24.4.  */
 795           handlerlist = handlerlist->next;
 796           NEXT;
 797
 798         CASE (Bunwind_protect): /* FIXME: avoid closure for lexbind.  */
 799           {
 800             Lisp_Object handler = POP;
 801             /* Support for a function here is new in 24.4.  */
 802             record_unwind_protect (FUNCTIONP (handler) ? bcall0 : prog_ignore,
 803                                    handler);
 804             NEXT;
 805           }
 806
 807         CASE (Bcondition_case):         /* Obsolete since 24.4.  */
 808           {
 809             Lisp_Object handlers = POP, body = POP;
 810             TOP = internal_lisp_condition_case (TOP, body, handlers);
 811             NEXT;
 812           }
 813
 814         CASE (Btemp_output_buffer_setup): /* Obsolete since 24.1.  */
 815           CHECK_STRING (TOP);
 816           temp_output_buffer_setup (SSDATA (TOP));
 817           TOP = Vstandard_output;
 818           NEXT;
 819
 820         CASE (Btemp_output_buffer_show): /* Obsolete since 24.1.  */
 821           {
 822             Lisp_Object v1 = POP;
 823             temp_output_buffer_show (TOP);
 824             TOP = v1;
 825             /* pop binding of standard-output */
 826             unbind_to (SPECPDL_INDEX () - 1, Qnil);
 827             NEXT;
 828           }
 829
 830         CASE (Bnth):
 831           {
 832             Lisp_Object v2 = POP, v1 = TOP;
 833             CHECK_NUMBER (v1);
 834             for (EMACS_INT n = XINT (v1); 0 < n && CONSP (v2); n--)
 835               {
 836                 v2 = XCDR (v2);
 837                 rarely_quit (n);
 838               }
 839             TOP = CAR (v2);
 840             NEXT;
 841           }
 842
 843         CASE (Bsymbolp):
 844           TOP = SYMBOLP (TOP) ? Qt : Qnil;
 845           NEXT;
 846
 847         CASE (Bconsp):
 848           TOP = CONSP (TOP) ? Qt : Qnil;
 849           NEXT;
 850
 851         CASE (Bstringp):
 852           TOP = STRINGP (TOP) ? Qt : Qnil;
 853           NEXT;
 854
 855         CASE (Blistp):
 856           TOP = CONSP (TOP) || NILP (TOP) ? Qt : Qnil;
 857           NEXT;
 858
 859         CASE (Bnot):
 860           TOP = NILP (TOP) ? Qt : Qnil;
 861           NEXT;
 862
 863         CASE (Bcons):
 864           {
 865             Lisp_Object v1 = POP;
 866             TOP = Fcons (TOP, v1);
 867             NEXT;
 868           }
 869
 870         CASE (Blist1):
 871           TOP = list1 (TOP);
 872           NEXT;
 873
 874         CASE (Blist2):
 875           {
 876             Lisp_Object v1 = POP;
 877             TOP = list2 (TOP, v1);
 878             NEXT;
 879           }
 880
 881         CASE (Blist3):
 882           DISCARD (2);
 883           TOP = Flist (3, &TOP);
 884           NEXT;
 885
 886         CASE (Blist4):
 887           DISCARD (3);
 888           TOP = Flist (4, &TOP);
 889           NEXT;
 890
 891         CASE (BlistN):
 892           op = FETCH;
 893           DISCARD (op - 1);
 894           TOP = Flist (op, &TOP);
 895           NEXT;
 896
 897         CASE (Blength):
 898           TOP = Flength (TOP);
 899           NEXT;
 900
 901         CASE (Baref):
 902           {
 903             Lisp_Object v1 = POP;
 904             TOP = Faref (TOP, v1);
 905             NEXT;
 906           }
 907
 908         CASE (Baset):
 909           {
 910             Lisp_Object v2 = POP, v1 = POP;
 911             TOP = Faset (TOP, v1, v2);
 912             NEXT;
 913           }
 914
 915         CASE (Bsymbol_value):
 916           TOP = Fsymbol_value (TOP);
 917           NEXT;
 918
 919         CASE (Bsymbol_function):
 920           TOP = Fsymbol_function (TOP);
 921           NEXT;
 922
 923         CASE (Bset):
 924           {
 925             Lisp_Object v1 = POP;
 926             TOP = Fset (TOP, v1);
 927             NEXT;
 928           }
 929
 930         CASE (Bfset):
 931           {
 932             Lisp_Object v1 = POP;
 933             TOP = Ffset (TOP, v1);
 934             NEXT;
 935           }
 936
 937         CASE (Bget):
 938           {
 939             Lisp_Object v1 = POP;
 940             TOP = Fget (TOP, v1);
 941             NEXT;
 942           }
 943
 944         CASE (Bsubstring):
 945           {
 946             Lisp_Object v2 = POP, v1 = POP;
 947             TOP = Fsubstring (TOP, v1, v2);
 948             NEXT;
 949           }
 950
 951         CASE (Bconcat2):
 952           DISCARD (1);
 953           TOP = Fconcat (2, &TOP);
 954           NEXT;
 955
 956         CASE (Bconcat3):
 957           DISCARD (2);
 958           TOP = Fconcat (3, &TOP);
 959           NEXT;
 960
 961         CASE (Bconcat4):
 962           DISCARD (3);
 963           TOP = Fconcat (4, &TOP);
 964           NEXT;
 965
 966         CASE (BconcatN):
 967           op = FETCH;
 968           DISCARD (op - 1);
 969           TOP = Fconcat (op, &TOP);
 970           NEXT;
 971
 972         CASE (Bsub1):
 973           TOP = INTEGERP (TOP) ? make_number (XINT (TOP) - 1) : Fsub1 (TOP);
 974           NEXT;
 975
 976         CASE (Badd1):
 977           TOP = INTEGERP (TOP) ? make_number (XINT (TOP) + 1) : Fadd1 (TOP);
 978           NEXT;
 979
 980         CASE (Beqlsign):
 981           {
 982             Lisp_Object v2 = POP, v1 = TOP;
 983             if (FLOATP (v1) || FLOATP (v2))
 984               TOP = arithcompare (v1, v2, ARITH_EQUAL);
 985             else
 986               {
 987                 CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v1);
 988                 CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (v2);
 989                 TOP = EQ (v1, v2) ? Qt : Qnil;
 990               }
 991             NEXT;
 992           }
 993
 994         CASE (Bgtr):
 995           {
 996             Lisp_Object v1 = POP;
 997             TOP = arithcompare (TOP, v1, ARITH_GRTR);
 998             NEXT;
 999           }
1000
1001         CASE (Blss):
1002           {
1003             Lisp_Object v1 = POP;
1004             TOP = arithcompare (TOP, v1, ARITH_LESS);
1005             NEXT;
1006           }
1007
1008         CASE (Bleq):
1009           {
1010             Lisp_Object v1 = POP;
1011             TOP = arithcompare (TOP, v1, ARITH_LESS_OR_EQUAL);
1012             NEXT;
1013           }
1014
1015         CASE (Bgeq):
1016           {
1017             Lisp_Object v1 = POP;
1018             TOP = arithcompare (TOP, v1, ARITH_GRTR_OR_EQUAL);
1019             NEXT;
1020           }
1021
1022         CASE (Bdiff):
1023           DISCARD (1);
1024           TOP = Fminus (2, &TOP);
1025           NEXT;
1026
1027         CASE (Bnegate):
1028           TOP = INTEGERP (TOP) ? make_number (- XINT (TOP)) : Fminus (1, &TOP);
1029           NEXT;
1030
1031         CASE (Bplus):
1032           DISCARD (1);
1033           TOP = Fplus (2, &TOP);
1034           NEXT;
1035
1036         CASE (Bmax):
1037           DISCARD (1);
1038           TOP = Fmax (2, &TOP);
1039           NEXT;
1040
1041         CASE (Bmin):
1042           DISCARD (1);
1043           TOP = Fmin (2, &TOP);
1044           NEXT;
1045
1046         CASE (Bmult):
1047           DISCARD (1);
1048           TOP = Ftimes (2, &TOP);
1049           NEXT;
1050
1051         CASE (Bquo):
1052           DISCARD (1);
1053           TOP = Fquo (2, &TOP);
1054           NEXT;
1055
1056         CASE (Brem):
1057           {
1058             Lisp_Object v1 = POP;
1059             TOP = Frem (TOP, v1);
1060             NEXT;
1061           }
1062
1063         CASE (Bpoint):
1064           PUSH (make_natnum (PT));
1065           NEXT;
1066
1067         CASE (Bgoto_char):
1068           TOP = Fgoto_char (TOP);
1069           NEXT;
1070
1071         CASE (Binsert):
1072           TOP = Finsert (1, &TOP);
1073           NEXT;
1074
1075         CASE (BinsertN):
1076           op = FETCH;
1077           DISCARD (op - 1);
1078           TOP = Finsert (op, &TOP);
1079           NEXT;
1080
1081         CASE (Bpoint_max):
1082           {
1083             Lisp_Object v1;
1084             XSETFASTINT (v1, ZV);
1085             PUSH (v1);
1086             NEXT;
1087           }
1088
1089         CASE (Bpoint_min):
1090           PUSH (make_natnum (BEGV));
1091           NEXT;
1092
1093         CASE (Bchar_after):
1094           TOP = Fchar_after (TOP);
1095           NEXT;
1096
1097         CASE (Bfollowing_char):
1098           PUSH (Ffollowing_char ());
1099           NEXT;
1100
1101         CASE (Bpreceding_char):
1102           PUSH (Fprevious_char ());
1103           NEXT;
1104
1105         CASE (Bcurrent_column):
1106           PUSH (make_natnum (current_column ()));
1107           NEXT;
1108
1109         CASE (Bindent_to):
1110           TOP = Findent_to (TOP, Qnil);
1111           NEXT;
1112
1113         CASE (Beolp):
1114           PUSH (Feolp ());
1115           NEXT;
1116
1117         CASE (Beobp):
1118           PUSH (Feobp ());
1119           NEXT;
1120
1121         CASE (Bbolp):
1122           PUSH (Fbolp ());
1123           NEXT;
1124
1125         CASE (Bbobp):
1126           PUSH (Fbobp ());
1127           NEXT;
1128
1129         CASE (Bcurrent_buffer):
1130           PUSH (Fcurrent_buffer ());
1131           NEXT;
1132
1133         CASE (Bset_buffer):
1134           TOP = Fset_buffer (TOP);
1135           NEXT;
1136
1137         CASE (Binteractive_p):  /* Obsolete since 24.1.  */
1138           PUSH (call0 (intern ("interactive-p")));
1139           NEXT;
1140
1141         CASE (Bforward_char):
1142           TOP = Fforward_char (TOP);
1143           NEXT;
1144
1145         CASE (Bforward_word):
1146           TOP = Fforward_word (TOP);
1147           NEXT;
1148
1149         CASE (Bskip_chars_forward):
1150           {
1151             Lisp_Object v1 = POP;
1152             TOP = Fskip_chars_forward (TOP, v1);
1153             NEXT;
1154           }
1155
1156         CASE (Bskip_chars_backward):
1157           {
1158             Lisp_Object v1 = POP;
1159             TOP = Fskip_chars_backward (TOP, v1);
1160             NEXT;
1161           }
1162
1163         CASE (Bforward_line):
1164           TOP = Fforward_line (TOP);
1165           NEXT;
1166
1167         CASE (Bchar_syntax):
1168           {
1169             CHECK_CHARACTER (TOP);
1170             int c = XFASTINT (TOP);
1171             if (NILP (BVAR (current_buffer, enable_multibyte_characters)))
1172               MAKE_CHAR_MULTIBYTE (c);
1173             XSETFASTINT (TOP, syntax_code_spec[SYNTAX (c)]);
1174           }
1175           NEXT;
1176
1177         CASE (Bbuffer_substring):
1178           {
1179             Lisp_Object v1 = POP;
1180             TOP = Fbuffer_substring (TOP, v1);
1181             NEXT;
1182           }
1183
1184         CASE (Bdelete_region):
1185           {
1186             Lisp_Object v1 = POP;
1187             TOP = Fdelete_region (TOP, v1);
1188             NEXT;
1189           }
1190
1191         CASE (Bnarrow_to_region):
1192           {
1193             Lisp_Object v1 = POP;
1194             TOP = Fnarrow_to_region (TOP, v1);
1195             NEXT;
1196           }
1197
1198         CASE (Bwiden):
1199           PUSH (Fwiden ());
1200           NEXT;
1201
1202         CASE (Bend_of_line):
1203           TOP = Fend_of_line (TOP);
1204           NEXT;
1205
1206         CASE (Bset_marker):
1207           {
1208             Lisp_Object v2 = POP, v1 = POP;
1209             TOP = Fset_marker (TOP, v1, v2);
1210             NEXT;
1211           }
1212
1213         CASE (Bmatch_beginning):
1214           TOP = Fmatch_beginning (TOP);
1215           NEXT;
1216
1217         CASE (Bmatch_end):
1218           TOP = Fmatch_end (TOP);
1219           NEXT;
1220
1221         CASE (Bupcase):
1222           TOP = Fupcase (TOP);
1223           NEXT;
1224
1225         CASE (Bdowncase):
1226           TOP = Fdowncase (TOP);
1227           NEXT;
1228
1229         CASE (Bstringeqlsign):
1230           {
1231             Lisp_Object v1 = POP;
1232             TOP = Fstring_equal (TOP, v1);
1233             NEXT;
1234           }
1235
1236         CASE (Bstringlss):
1237           {
1238             Lisp_Object v1 = POP;
1239             TOP = Fstring_lessp (TOP, v1);
1240             NEXT;
1241           }
1242
1243         CASE (Bequal):
1244           {
1245             Lisp_Object v1 = POP;
1246             TOP = Fequal (TOP, v1);
1247             NEXT;
1248           }
1249
1250         CASE (Bnthcdr):
1251           {
1252             Lisp_Object v1 = POP;
1253             TOP = Fnthcdr (TOP, v1);
1254             NEXT;
1255           }
1256
1257         CASE (Belt):
1258           {
1259             if (CONSP (TOP))
1260               {
1261                 /* Exchange args and then do nth.  */
1262                 Lisp_Object v2 = POP, v1 = TOP;
1263                 CHECK_NUMBER (v2);
1264                 for (EMACS_INT n = XINT (v2); 0 < n && CONSP (v1); n--)
1265                   {
1266                     v1 = XCDR (v1);
1267                     rarely_quit (n);
1268                   }
1269                 TOP = CAR (v1);
1270               }
1271             else
1272               {
1273                 Lisp_Object v1 = POP;
1274                 TOP = Felt (TOP, v1);
1275               }
1276             NEXT;
1277           }
1278
1279         CASE (Bmember):
1280           {
1281             Lisp_Object v1 = POP;
1282             TOP = Fmember (TOP, v1);
1283             NEXT;
1284           }
1285
1286         CASE (Bassq):
1287           {
1288             Lisp_Object v1 = POP;
1289             TOP = Fassq (TOP, v1);
1290             NEXT;
1291           }
1292
1293         CASE (Bnreverse):
1294           TOP = Fnreverse (TOP);
1295           NEXT;
1296
1297         CASE (Bsetcar):
1298           {
1299             Lisp_Object v1 = POP;
1300             TOP = Fsetcar (TOP, v1);
1301             NEXT;
1302           }
1303
1304         CASE (Bsetcdr):
1305           {
1306             Lisp_Object v1 = POP;
1307             TOP = Fsetcdr (TOP, v1);
1308             NEXT;
1309           }
1310
1311         CASE (Bcar_safe):
1312           TOP = CAR_SAFE (TOP);
1313           NEXT;
1314
1315         CASE (Bcdr_safe):
1316           TOP = CDR_SAFE (TOP);
1317           NEXT;
1318
1319         CASE (Bnconc):
1320           DISCARD (1);
1321           TOP = Fnconc (2, &TOP);
1322           NEXT;
1323
1324         CASE (Bnumberp):
1325           TOP = NUMBERP (TOP) ? Qt : Qnil;
1326           NEXT;
1327
1328         CASE (Bintegerp):
1329           TOP = INTEGERP (TOP) ? Qt : Qnil;
1330           NEXT;
1331
1332 #if BYTE_CODE_SAFE
1333           /* These are intentionally written using 'case' syntax,
1334              because they are incompatible with the threaded
1335              interpreter.  */
1336
1337         case Bset_mark:
1338           error ("set-mark is an obsolete bytecode");
1339           break;
1340         case Bscan_buffer:
1341           error ("scan-buffer is an obsolete bytecode");
1342           break;
1343 #endif
1344
1345         CASE_ABORT:
1346           /* Actually this is Bstack_ref with offset 0, but we use Bdup
1347              for that instead.  */
1348           /* CASE (Bstack_ref): */
1349           call3 (Qerror,
1350                  build_string ("Invalid byte opcode: op=%s, ptr=%d"),
1351                  make_number (op),
1352                  make_number (pc - 1 - bytestr_data));
1353
1354           /* Handy byte-codes for lexical binding.  */
1355         CASE (Bstack_ref1):
1356         CASE (Bstack_ref2):
1357         CASE (Bstack_ref3):
1358         CASE (Bstack_ref4):
1359         CASE (Bstack_ref5):
1360           {
1361             Lisp_Object v1 = top[Bstack_ref - op];
1362             PUSH (v1);
1363             NEXT;
1364           }
1365         CASE (Bstack_ref6):
1366           {
1367             Lisp_Object v1 = top[- FETCH];
1368             PUSH (v1);
1369             NEXT;
1370           }
1371         CASE (Bstack_ref7):
1372           {
1373             Lisp_Object v1 = top[- FETCH2];
1374             PUSH (v1);
1375             NEXT;
1376           }
1377         CASE (Bstack_set):
1378           /* stack-set-0 = discard; stack-set-1 = discard-1-preserve-tos.  */
1379           {
1380             Lisp_Object *ptr = top - FETCH;
1381             *ptr = POP;
1382             NEXT;
1383           }
1384         CASE (Bstack_set2):
1385           {
1386             Lisp_Object *ptr = top - FETCH2;
1387             *ptr = POP;
1388             NEXT;
1389           }
1390         CASE (BdiscardN):
1391           op = FETCH;
1392           if (op & 0x80)
1393             {
1394               op &= 0x7F;
1395               top[-op] = TOP;
1396             }
1397           DISCARD (op);
1398           NEXT;
1399
1400         CASE (Bswitch):
1401           {
1402             /* TODO: Perhaps introduce another byte-code for switch when the
1403                number of cases is less, which uses a simple vector for linear
1404                search as the jump table.  */
1405             Lisp_Object jmp_table = POP;
1406             if (BYTE_CODE_SAFE && !HASH_TABLE_P (jmp_table))
1407               emacs_abort ();
1408             Lisp_Object v1 = POP;
1409             ptrdiff_t i;
1410             struct Lisp_Hash_Table *h = XHASH_TABLE (jmp_table);
1411
1412             /* h->count is a faster approximation for HASH_TABLE_SIZE (h)
1413                here. */
1414             if (h->count <= 5)
1415               { /* Do a linear search if there are not many cases
1416                    FIXME: 5 is arbitrarily chosen.  */
1417                 Lisp_Object hash_code = h->test.cmpfn
1418                   ? make_number (h->test.hashfn (&h->test, v1)) : Qnil;
1419
1420                 for (i = h->count; 0 <= --i; )
1421                   if (EQ (v1, HASH_KEY (h, i))
1422                       || (h->test.cmpfn
1423                           && EQ (hash_code, HASH_HASH (h, i))
1424                           && h->test.cmpfn (&h->test, v1, HASH_KEY (h, i))))
1425                     break;
1426
1427               }
1428             else
1429               i = hash_lookup (h, v1, NULL);
1430
1431             if (i >= 0)
1432               {
1433                 Lisp_Object val = HASH_VALUE (h, i);
1434                 if (BYTE_CODE_SAFE && !INTEGERP (val))
1435                   emacs_abort ();
1436                 op = XINT (val);
1437                 goto op_branch;
1438               }
1439           }
1440           NEXT;
1441
1442         CASE_DEFAULT
1443         CASE (Bconstant):
1444           if (BYTE_CODE_SAFE
1445               && ! (Bconstant <= op && op < Bconstant + const_length))
1446             emacs_abort ();
1447           PUSH (vectorp[op - Bconstant]);
1448           NEXT;
1449         }
1450     }
1451
1452  exit:
1453
1454   /* Binds and unbinds are supposed to be compiled balanced.  */
1455   if (SPECPDL_INDEX () != count)
1456     {
1457       if (SPECPDL_INDEX () > count)
1458         unbind_to (count, Qnil);
1459       error ("binding stack not balanced (serious byte compiler bug)");
1460     }
1461
1462   Lisp_Object result = TOP;
1463   SAFE_FREE ();
1464   return result;
1465 }
1466
1467 /* `args_template' has the same meaning as in exec_byte_code() above.  */
1468 Lisp_Object
1469 get_byte_code_arity (Lisp_Object args_template)
1470 {
1471   eassert (NATNUMP (args_template));
1472   EMACS_INT at = XINT (args_template);
1473   bool rest = (at & 128) != 0;
1474   int mandatory = at & 127;
1475   EMACS_INT nonrest = at >> 8;
1476
1477   return Fcons (make_number (mandatory),
1478                 rest ? Qmany : make_number (nonrest));
1479 }
1480
1481 void
1482 syms_of_bytecode (void)
1483 {
1484   defsubr (&Sbyte_code);
1485
1486 #ifdef BYTE_CODE_METER
1487
1488   DEFVAR_LISP ("byte-code-meter", Vbyte_code_meter,
1489                doc: /* A vector of vectors which holds a histogram of byte-code usage.
1490 \(aref (aref byte-code-meter 0) CODE) indicates how many times the byte
1491 opcode CODE has been executed.
1492 \(aref (aref byte-code-meter CODE1) CODE2), where CODE1 is not 0,
1493 indicates how many times the byte opcodes CODE1 and CODE2 have been
1494 executed in succession.  */);
1495
1496   DEFVAR_BOOL ("byte-metering-on", byte_metering_on,
1497                doc: /* If non-nil, keep profiling information on byte code usage.
1498 The variable byte-code-meter indicates how often each byte opcode is used.
1499 If a symbol has a property named `byte-code-meter' whose value is an
1500 integer, it is incremented each time that symbol's function is called.  */);
1501
1502   byte_metering_on = false;
1503   Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
1504   DEFSYM (Qbyte_code_meter, "byte-code-meter");
1505   {
1506     int i = 256;
1507     while (i--)
1508       ASET (Vbyte_code_meter, i,
1509            Fmake_vector (make_number (256), make_number (0)));
1510   }
1511 #endif
1512 }