libguile/tags.h

   1 /* classes: h_files */
   2
   3 #ifndef TAGSH
   4 #define TAGSH
   5 /* Copyright (C) 1995, 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2, or (at your option)
  10  * any later version.
  11  *
  12  * This program 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 this software; see the file COPYING.  If not, write to
  19  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20  * Boston, MA 02111-1307 USA
  21  *
  22  * As a special exception, the Free Software Foundation gives permission
  23  * for additional uses of the text contained in its release of GUILE.
  24  *
  25  * The exception is that, if you link the GUILE library with other files
  26  * to produce an executable, this does not by itself cause the
  27  * resulting executable to be covered by the GNU General Public License.
  28  * Your use of that executable is in no way restricted on account of
  29  * linking the GUILE library code into it.
  30  *
  31  * This exception does not however invalidate any other reasons why
  32  * the executable file might be covered by the GNU General Public License.
  33  *
  34  * This exception applies only to the code released by the
  35  * Free Software Foundation under the name GUILE.  If you copy
  36  * code from other Free Software Foundation releases into a copy of
  37  * GUILE, as the General Public License permits, the exception does
  38  * not apply to the code that you add in this way.  To avoid misleading
  39  * anyone as to the status of such modified files, you must delete
  40  * this exception notice from them.
  41  *
  42  * If you write modifications of your own for GUILE, it is your choice
  43  * whether to permit this exception to apply to your modifications.
  44  * If you do not wish that, delete this exception notice.  */
  45
  46 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  47    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  48
  49 \f
  50
  51 /** This file defines the format of SCM values and cons pairs.
  52  ** It is here that tag bits are assigned for various purposes.
  53  **/
  54
  55 \f
  56
  57 /* In the beginning was the Word:
  58  */
  59 typedef long SCM;
  60
  61
  62
  63 /* Cray machines have pointers that are incremented once for each word,
  64  * rather than each byte, the 3 most significant bits encode the byte
  65  * within the word.  The following macros deal with this by storing the
  66  * native Cray pointers like the ones that looks like scm expects.  This
  67  * is done for any pointers that might appear in the car of a scm_cell, pointers
  68  * to scm_vector elts, functions, &c are not munged.
  69  */
  70 #ifdef _UNICOS
  71 # define SCM2PTR(x) ((int)(x) >> 3)
  72 # define PTR2SCM(x) (((SCM)(x)) << 3)
  73 # define SCM_POINTERS_MUNGED
  74 #else
  75 # define SCM2PTR(x) (x)
  76 # define PTR2SCM(x) ((SCM)(x))
  77 #endif /* def _UNICOS */
  78
  79 \f
  80 /* SCM variables can contain:
  81  *
  82  * Non-objects -- meaning that the tag-related macros don't apply to them
  83  * in the usual way.
  84  *
  85  * Immediates -- meaning that the variable contains an entire Scheme object.
  86  *
  87  * Non-immediates -- meaning that the variable holds a (possibly
  88  * tagged) pointer into the cons pair heap.
  89  *
  90  * Non-objects are distinguished from other values by careful coding
  91  * only (i.e., programmers must keep track of any SCM variables they
  92  * create that don't contain ordinary scheme values).
  93  *
  94  * All immediates and non-immediates must have a 0 in bit 0.  Only
  95  * non-object values can have a 1 in bit 0.  In some cases, bit 0 of a
  96  * word in the heap is used for the GC tag so during garbage
  97  * collection, that bit might be 1 even in an immediate or
  98  * non-immediate value.  In other cases, bit 0 of a word in the heap
  99  * is used to tag a pointer to a GLOC (VM global variable address) or
 100  * the header of a struct.  But whenever an SCM variable holds a
 101  * normal Scheme value, bit 0 is 0.
 102  *
 103  * Immediates and non-immediates are distinguished by bits two and four.
 104  * Immediate values must have a 1 in at least one of those bits.  Does
 105  * this (or any other detail of tagging) seem arbitrary?  Try changing it!
 106  * (Not always impossible but it is fair to say that many details of tags
 107  * are mutually dependent).  */
 108
 109 #define SCM_IMP(x)              (6 & (SCM)(x))
 110 #define SCM_NIMP(x)             (!SCM_IMP(x))
 111
 112 /* Here is a summary of tagging in SCM values as they might occur in
 113  * SCM variables or in the heap.
 114  *
 115  * low bits    meaning
 116  *
 117  *
 118  * 0            Most objects except...
 119  * 1            ...glocs and structs (this tag valid only in a SCM_CAR or
 120  *              in the header of a struct's data).
 121  *
 122  * 00           heap addresses and many immediates (not integers)
 123  * 01           glocs/structs, some tc7_ codes
 124  * 10           immediate integers
 125  * 11           various tc7_ codes including, tc16_ codes.
 126  *
 127  *
 128  * 000          heap address
 129  * 001          glocs/structs
 130  * 010          integer
 131  * 011          closure
 132  * 100          immediates
 133  * 101          tc7_
 134  * 110          integer
 135  * 111          tc7_
 136  *
 137  *
 138  * 100 --- IMMEDIATES
 139  *
 140  * Looking at the seven final bits of an immediate:
 141  *
 142  * 0000-100     short instruction
 143  * 0001-100     short instruction
 144  * 0010-100     short instruction
 145  * 0011-100     short instruction
 146  * 0100-100     short instruction
 147  * 0101-100     short instruction
 148  * 0110-100     various immediates and long instructions
 149  * 0111-100     short instruction
 150  * 1000-100     short instruction
 151  * 1001-100     short instruction
 152  * 1010-100     short instruction
 153  * 1011-100     short instruction
 154  * 1100-100     short instruction
 155  * 1101-100     short instruction
 156  * 1110-100     immediate characters
 157  * 1111-100     ilocs
 158  *
 159  * Some of the 0110100 immediates are long instructions (they dispatch
 160  * in two steps compared to one step for a short instruction).
 161  * The two steps are, (1) dispatch on 7 bits to the long instruction
 162  * handler, (2) dispatch on 7 additional bits.
 163  *
 164  * One way to think of it is that there are 128 short instructions,
 165  * with the 13 immediates above being some of the most interesting.
 166  *
 167  * Also noteworthy are the groups of 16 7-bit instructions implied by
 168  * some of the 3-bit tags.   For example, closure references consist
 169  * of an 8-bit aligned address tagged with 011.  There are 16 identical 7-bit
 170  * instructions, all ending 011, which are invoked by evaluating closures.
 171  *
 172  * In other words, if you hand the evaluator a closure, the evaluator
 173  * treats the closure as a graph of virtual machine instructions.
 174  * A closure is a pair with a pointer to the body of the procedure
 175  * in the CDR and a pointer to the environment of the closure in the CAR.
 176  * The environment pointer is tagged 011 which implies that the least
 177  * significant 7 bits of the environment pointer also happen to be
 178  * a virtual machine instruction we could call "SELF" (for self-evaluating
 179  * object).
 180  *
 181  * A less trivial example are the 16 instructions ending 000.  If those
 182  * bits tag the CAR of a pair, then evidently the pair is an ordinary
 183  * cons pair and should be evaluated as a procedure application.  The sixteen,
 184  * 7-bit 000 instructions are all "NORMAL-APPLY"  (Things get trickier.
 185  * For example, if the CAR of a procedure application is a symbol, the NORMAL-APPLY
 186  * instruction will, as a side effect, overwrite that CAR with a new instruction
 187  * that contains a cached address for the variable named by the symbol.)
 188  *
 189  * Here is a summary of tags in the CAR of a non-immediate:
 190  *
 191  *   HEAP CELL: G=gc_mark; 1 during mark, 0 other times.
 192  *
 193  * cons    ..........SCM car..............0  ...........SCM cdr.............G
 194  * gloc    ..........SCM vcell..........001  ...........SCM cdr.............G
 195  * struct  ..........void * type........001  ...........void * data.........G
 196  * closure ..........SCM code...........011  ...........SCM env.............G
 197  * tc7     .........long length....Gxxxx1S1  ..........void *data............
 198  *
 199  *
 200  *
 201  * 101 & 111 --- tc7_ types
 202  *
 203  *              tc7_tags are 7 bit tags ending in 1x1.  These tags
 204  *              occur only in the CAR of heap cells, and have the
 205  *              handy property that all bits of the CAR above the
 206  *              bottom eight can be used to store a length, thus
 207  *              saving a word in the body itself.  Thus, we use them
 208  *              for strings, symbols, and vectors (among other
 209  *              things).
 210  *
 211  *              SCM_LENGTH returns the bits in "length" (see the diagram).
 212  *              SCM_CHARS returns the data cast to "char *"
 213  *              SCM_CDR returns the data cast to "SCM"
 214  *              TYP7(X) returns bits 0...6 of SCM_CAR (X)
 215  *
 216  *              For the interpretation of SCM_LENGTH and SCM_CHARS
 217  *              that applies to a particular type, see the header file
 218  *              for that type.
 219  *
 220  *              Sometimes we choose the bottom seven bits carefully,
 221  *              so that the 2-valued bit (called S bit) can be masked
 222  *              off to reveal a common type.
 223  *
 224  *              TYP7S(X) returns TYP7, but masking out the option bit S.
 225  *
 226  *              For example, all strings have 0010 in the 'xxxx' bits
 227  *              in the diagram above, the S bit says whether it's a
 228  *              substring.
 229  *
 230  *              for example:
 231  *                                                      S
 232  *                      scm_tc7_string          = G0010101
 233  *                      scm_tc7_substring       = G0010111
 234  *
 235  *              TYP7S turns both string tags into tc7_string; thus,
 236  *              testing TYP7S against tc7_string is a quick way to
 237  *              test for any kind of string, shared or unshared.
 238  *
 239  *              Some TC7 types are subdivided into 256 subtypes giving
 240  *              rise to the macros:
 241  *
 242  *              TYP16
 243  *              TYP16S
 244  *              GCTYP16
 245  *
 246  *              TYP16S functions similarly wrt to TYP16 as TYP7S to TYP7,
 247  *              but a different option bit is used (bit 2 for TYP7S,
 248  *              bit 8 for TYP16S).
 249  * */
 250
 251
 252
 253 \f
 254 /* {Non-immediate values.}
 255  *
 256  * If X is non-immediate, it is necessary to look at SCM_CAR (X) to
 257  * figure out Xs type.  X may be a cons pair, in which case the value
 258  * SCM_CAR (x) will be either an immediate or non-immediate value.  X
 259  * may be something other than a cons pair, in which case the value
 260  * SCM_CAR (x) will be a non-object value.
 261  *
 262  * All immediates and non-immediates have a 0 in bit 0.  We
 263  * additionally preserve the invariant that all non-object values
 264  * stored in the SCM_CAR of a non-immediate object have a 1 in bit 1:
 265  */
 266
 267 #define SCM_NCONSP(x) (1 & SCM_CAR(x))
 268 #define SCM_CONSP(x) (!SCM_NCONSP(x))
 269
 270
 271 /* SCM_ECONSP should be used instead of SCM_CONSP at places where GLOCS
 272  * can be expected to occur.
 273  */
 274 #define SCM_ECONSP(x) (SCM_CONSP (x) \
 275                        || (SCM_TYP3(x) == 1 \
 276                            && SCM_CDR (SCM_CAR (x) - 1) != 0))
 277 #define SCM_NECONSP(x) (SCM_NCONSP(x) \
 278                         && (SCM_TYP3(x) != 1 \
 279                             || SCM_CDR (SCM_CAR (x) - 1) == 0))
 280
 281 \f
 282
 283 #define SCM_CELLP(x)    (!SCM_NCELLP(x))
 284 #define SCM_NCELLP(x)   ((sizeof(scm_cell)-1) & (SCM)(x))
 285
 286 /* See numbers.h for macros relating to immediate integers.
 287  */
 288
 289 #define SCM_ITAG3(x)            (7 & (SCM)x)
 290 #define SCM_TYP3(x)             (7 & SCM_CAR(x))
 291 #define scm_tc3_cons            0
 292 #define scm_tc3_cons_gloc       1
 293 #define scm_tc3_int_1           2
 294 #define scm_tc3_closure         3
 295 #define scm_tc3_imm24           4
 296 #define scm_tc3_tc7_1           5
 297 #define scm_tc3_int_2           6
 298 #define scm_tc3_tc7_2           7
 299
 300
 301 /*
 302  * Do not change the three bit tags.
 303  */
 304
 305
 306 #define SCM_TYP7(x)             (SCM_CAR(x) & 0x7f)
 307 #define SCM_TYP7S(x)            (SCM_CAR(x) & (0x7f & ~2))
 308
 309
 310 #define SCM_TYP16(x)            (0xffff & SCM_CAR(x))
 311 #define SCM_TYP16S(x)           (0xfeff & SCM_CAR(x))
 312 #define SCM_GCTYP16(x)          (0xff7f & SCM_CAR(x))
 313
 314
 315
 316 /* Testing and Changing GC Marks in Various Standard Positions
 317  */
 318 #define SCM_GCMARKP(x)          (1 & SCM_CDR(x))
 319 #define SCM_GC8MARKP(x)         (0x80 & SCM_CAR(x))
 320 #define SCM_SETGCMARK(x)        SCM_SETOR_CDR (x,1)
 321 #define SCM_CLRGCMARK(x)        SCM_SETAND_CDR (x, ~1L)
 322 #define SCM_SETGC8MARK(x)       SCM_SETOR_CAR (x, 0x80)
 323 #define SCM_CLRGC8MARK(x)       SCM_SETAND_CAR (x, ~0x80L)
 324
 325
 326 \f
 327
 328 /* couple */
 329 #define scm_tc7_ssymbol         5
 330 #define scm_tc7_msymbol         7
 331
 332 /* couple */
 333 #define scm_tc7_vector          13
 334 #define scm_tc7_wvect           15
 335
 336 /* couple */
 337 #define scm_tc7_string          21
 338 #define scm_tc7_substring       23
 339
 340 /* Many of the following should be turned
 341  * into structs or smobs.  We need back some
 342  * of these 7 bit tags!
 343  */
 344 #define scm_tc7_pws             31
 345 #define scm_tc7_lvector         39
 346
 347 #ifdef HAVE_ARRAYS
 348 #define scm_tc7_llvect          29
 349 #define scm_tc7_uvect           37
 350 #define scm_tc7_fvect           45
 351 #define scm_tc7_dvect           47
 352 #define scm_tc7_cvect           53
 353 #define scm_tc7_svect           55
 354 #define scm_tc7_bvect           71
 355 #define scm_tc7_byvect          77
 356 #define scm_tc7_ivect           79
 357 #endif
 358
 359 #define scm_tc7_contin          61
 360 #define scm_tc7_cclo            63
 361 #define scm_tc7_rpsubr          69
 362 #define scm_tc7_subr_0          85
 363 #define scm_tc7_subr_1          87
 364 #define scm_tc7_cxr             93
 365 #define scm_tc7_subr_3          95
 366 #define scm_tc7_subr_2          101
 367 #define scm_tc7_asubr           103
 368 #define scm_tc7_subr_1o         109
 369 #define scm_tc7_subr_2o         111
 370 #define scm_tc7_lsubr_2         117
 371 #define scm_tc7_lsubr           119
 372
 373
 374 /* There are 256 port subtypes.  Here are the first few.
 375  * These must agree with the init function in ports.c
 376  */
 377 #define scm_tc7_port            125
 378
 379 #define scm_tc16_fport          (scm_tc7_port + 0*256L)
 380 /* scm_tc16_pipe was here.  */
 381 #define scm_tc16_strport        (scm_tc7_port + 2*256L)
 382 #define scm_tc16_sfport         (scm_tc7_port + 3*256L)
 383
 384
 385 /* There are 256 smob subtypes.  Here are the first four.
 386  */
 387
 388 #define scm_tc7_smob            127 /* DO NOT CHANGE [**] */
 389
 390 /* [**] If you change scm_tc7_smob, you must also change
 391  * the places it is hard coded in this file and possibly others.
 392  */
 393
 394
 395 /* scm_tc_free_cell is also the 0th smob type.  We place this
 396  * in free cells to tell the conservative marker not to trace it.
 397  */
 398 #define scm_tc_free_cell        127
 399
 400 /* The 1st smob type:
 401  */
 402 #define scm_tc16_flo            0x017f
 403 #define scm_tc_flo              0x017fL
 404
 405 /* Some option bits begeinning at bit 16 of scm_tc16_flo:
 406  */
 407 #define SCM_REAL_PART           (1L<<16)
 408 #define SCM_IMAG_PART           (2L<<16)
 409 #define scm_tc_dblr             (scm_tc16_flo|SCM_REAL_PART)
 410 #define scm_tc_dblc             (scm_tc16_flo|SCM_REAL_PART|SCM_IMAG_PART)
 411
 412
 413 /* Smob types 2 and 3:
 414  */
 415 #define scm_tc16_bigpos         0x027f
 416 #define scm_tc16_bigneg         0x037f
 417
 418 /* Smob type 4: this is allocated, but not initialized cells;
 419    this is required to prevent the gc from hosing your cells if
 420    you have to allocate while creating the cell*/
 421
 422 #define scm_tc16_allocated      0x047f
 423
 424
 425 \f
 426 /* {Immediate Values}
 427  */
 428
 429 enum scm_tags
 430 {
 431   scm_tc8_char = 0xf4,
 432   scm_tc8_iloc = 0xfc
 433 };
 434
 435 #define SCM_ITAG8(X)            ((SCM)(X) & 0xff)
 436 #define SCM_MAKE_ITAG8(X, TAG)  (((X)<<8) + TAG)
 437 #define SCM_ITAG8_DATA(X)       ((X)>>8)
 438
 439
 440 \f
 441 /* Immediate Symbols, Special Symbols, Flags (various constants).
 442  */
 443
 444 /* SCM_ISYMP tests for ISPCSYM and ISYM */
 445 #define SCM_ISYMP(n)            ((0x187 & (SCM)(n))==4)
 446
 447 /* SCM_IFLAGP tests for ISPCSYM, ISYM and IFLAG */
 448 #define SCM_IFLAGP(n)           ((0x87 & (SCM)(n))==4)
 449 #define SCM_ISYMNUM(n)          ((SCM)((n)>>9))
 450 #define SCM_ISYMCHARS(n)        (scm_isymnames[SCM_ISYMNUM(n)])
 451 #define SCM_MAKSPCSYM(n)        (((n)<<9)+((n)<<3)+4L)
 452 #define SCM_MAKISYM(n)          (((n)<<9)+0x74L)
 453 #define SCM_MAKIFLAG(n)         (((n)<<9)+0x174L)
 454
 455 extern char *scm_isymnames[];   /* defined in print.c */
 456
 457 /* This table must agree with the declarations
 458  * in repl.c: {Names of immediate symbols}.
 459  *
 460  * These are used only in eval but their values
 461  * have to be allocated here.
 462  *
 463  */
 464
 465 #define SCM_IM_AND              SCM_MAKSPCSYM(0)
 466 #define SCM_IM_BEGIN            SCM_MAKSPCSYM(1)
 467 #define SCM_IM_CASE             SCM_MAKSPCSYM(2)
 468 #define SCM_IM_COND             SCM_MAKSPCSYM(3)
 469 #define SCM_IM_DO               SCM_MAKSPCSYM(4)
 470 #define SCM_IM_IF               SCM_MAKSPCSYM(5)
 471 #define SCM_IM_LAMBDA           SCM_MAKSPCSYM(6)
 472 #define SCM_IM_LET              SCM_MAKSPCSYM(7)
 473 #define SCM_IM_LETSTAR          SCM_MAKSPCSYM(8)
 474 #define SCM_IM_LETREC           SCM_MAKSPCSYM(9)
 475 #define SCM_IM_OR               SCM_MAKSPCSYM(10)
 476 #define SCM_IM_QUOTE            SCM_MAKSPCSYM(11)
 477 #define SCM_IM_SET_X            SCM_MAKSPCSYM(12)
 478 #define SCM_IM_DEFINE           SCM_MAKSPCSYM(13)
 479 #define SCM_IM_APPLY            SCM_MAKISYM(14)
 480 #define SCM_IM_CONT             SCM_MAKISYM(15)
 481 #define SCM_BOOL_F              SCM_MAKIFLAG(16)
 482 #define SCM_BOOL_T              SCM_MAKIFLAG(17)
 483 #define SCM_UNDEFINED           SCM_MAKIFLAG(18)
 484 #define SCM_EOF_VAL             SCM_MAKIFLAG(19)
 485 #define SCM_EOL                 SCM_MAKIFLAG(20)
 486 #define SCM_UNSPECIFIED         SCM_MAKIFLAG(21)
 487 #define SCM_IM_DISPATCH         SCM_MAKISYM(22)
 488 #define SCM_IM_SLOT_REF         SCM_MAKISYM(23)
 489 #define SCM_IM_SLOT_SET_X       SCM_MAKISYM(24)
 490
 491 /* Multi-language support */
 492
 493 #define SCM_IM_NIL_COND         SCM_MAKISYM(25)
 494 #define SCM_IM_NIL_IFY          SCM_MAKISYM(26)
 495 #define SCM_IM_T_IFY            SCM_MAKISYM(27)
 496 #define SCM_IM_0_COND           SCM_MAKISYM(28)
 497 #define SCM_IM_0_IFY            SCM_MAKISYM(29)
 498 #define SCM_IM_1_IFY            SCM_MAKISYM(30)
 499 #define SCM_IM_BIND             SCM_MAKISYM(31)
 500
 501 #define SCM_IM_DELAY            SCM_MAKISYM(32)
 502
 503 /* When a variable is unbound this is marked by the SCM_UNDEFINED
 504  * value.  The following is an unbound value which can be handled on
 505  * the Scheme level, i.e., it can be stored in and retrieved from a
 506  * Scheme variable.  This value is only intended to mark an unbound
 507  * slot in GOOPS.  It is needed now, but we should probably rewrite
 508  * the code which handles this value in C so that SCM_UNDEFINED can be
 509  * used instead.  It is not ideal to let this kind of unique and
 510  * strange values loose on the Scheme level.
 511  */
 512 #define SCM_UNBOUND             SCM_MAKIFLAG(33)
 513
 514 #define SCM_UNBNDP(x)   (SCM_UNDEFINED==(x))
 515
 516 \f
 517
 518 /* Dispatching aids: */
 519
 520
 521 /* For cons pairs with immediate values in the CAR
 522  */
 523
 524 #define scm_tcs_cons_imcar 2:case 4:case 6:case 10:\
 525  case 12:case 14:case 18:case 20:\
 526  case 22:case 26:case 28:case 30:\
 527  case 34:case 36:case 38:case 42:\
 528  case 44:case 46:case 50:case 52:\
 529  case 54:case 58:case 60:case 62:\
 530  case 66:case 68:case 70:case 74:\
 531  case 76:case 78:case 82:case 84:\
 532  case 86:case 90:case 92:case 94:\
 533  case 98:case 100:case 102:case 106:\
 534  case 108:case 110:case 114:case 116:\
 535  case 118:case 122:case 124:case 126
 536
 537 /* For cons pairs with non-immediate values in the SCM_CAR
 538  */
 539 #define scm_tcs_cons_nimcar 0:case 8:case 16:case 24:\
 540  case 32:case 40:case 48:case 56:\
 541  case 64:case 72:case 80:case 88:\
 542  case 96:case 104:case 112:case 120
 543
 544 /* A CONS_GLOC occurs in code.  It's CAR is a pointer to the
 545  * CDR of a variable.  The low order bits of the CAR are 001.
 546  * The CDR of the gloc is the code continuation.
 547  */
 548 #define scm_tcs_cons_gloc 1:case 9:case 17:case 25:\
 549  case 33:case 41:case 49:case 57:\
 550  case 65:case 73:case 81:case 89:\
 551  case 97:case 105:case 113:case 121
 552
 553 #define scm_tcs_closures   3:case 11:case 19:case 27:\
 554  case 35:case 43:case 51:case 59:\
 555  case 67:case 75:case 83:case 91:\
 556  case 99:case 107:case 115:case 123
 557
 558 #define scm_tcs_subrs scm_tc7_asubr:case scm_tc7_subr_0:case scm_tc7_subr_1:case scm_tc7_cxr:\
 559  case scm_tc7_subr_3:case scm_tc7_subr_2:case scm_tc7_rpsubr:case scm_tc7_subr_1o:\
 560  case scm_tc7_subr_2o:case scm_tc7_lsubr_2:case scm_tc7_lsubr
 561
 562 #define scm_tcs_symbols scm_tc7_ssymbol:case scm_tc7_msymbol
 563
 564 #define scm_tcs_bignums scm_tc16_bigpos:case scm_tc16_bigneg
 565
 566 #endif  /* TAGSH */