opcodes/m32r-asm.c

   1 /* Assembler interface for targets using CGEN. -*- C -*-
   2    CGEN: Cpu tools GENerator
   3
   4    THIS FILE IS MACHINE GENERATED WITH CGEN.
   5    - the resultant file is machine generated, cgen-asm.in isn't
   6
   7    Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2005, 2007
   8    Free Software Foundation, Inc.
   9
  10    This file is part of libopcodes.
  11
  12    This library is free software; you can redistribute it and/or modify
  13    it under the terms of the GNU General Public License as published by
  14    the Free Software Foundation; either version 3, or (at your option)
  15    any later version.
  16
  17    It is distributed in the hope that it will be useful, but WITHOUT
  18    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  20    License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program; if not, write to the Free Software Foundation, Inc.,
  24    51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  25
  26
  27 /* ??? Eventually more and more of this stuff can go to cpu-independent files.
  28    Keep that in mind.  */
  29
  30 #include "sysdep.h"
  31 #include <stdio.h>
  32 #include "ansidecl.h"
  33 #include "bfd.h"
  34 #include "symcat.h"
  35 #include "m32r-desc.h"
  36 #include "m32r-opc.h"
  37 #include "opintl.h"
  38 #include "xregex.h"
  39 #include "libiberty.h"
  40 #include "safe-ctype.h"
  41
  42 #undef  min
  43 #define min(a,b) ((a) < (b) ? (a) : (b))
  44 #undef  max
  45 #define max(a,b) ((a) > (b) ? (a) : (b))
  46
  47 static const char * parse_insn_normal
  48   (CGEN_CPU_DESC, const CGEN_INSN *, const char **, CGEN_FIELDS *);
  49 \f
  50 /* -- assembler routines inserted here.  */
  51
  52 /* -- asm.c */
  53 static const char * MISSING_CLOSING_PARENTHESIS = N_("missing `)'");
  54
  55 /* Handle '#' prefixes (i.e. skip over them).  */
  56
  57 static const char *
  58 parse_hash (CGEN_CPU_DESC cd ATTRIBUTE_UNUSED,
  59             const char **strp,
  60             int opindex ATTRIBUTE_UNUSED,
  61             long *valuep ATTRIBUTE_UNUSED)
  62 {
  63   if (**strp == '#')
  64     ++*strp;
  65   return NULL;
  66 }
  67
  68 /* Handle shigh(), high().  */
  69
  70 static const char *
  71 parse_hi16 (CGEN_CPU_DESC cd,
  72             const char **strp,
  73             int opindex,
  74             unsigned long *valuep)
  75 {
  76   const char *errmsg;
  77   enum cgen_parse_operand_result result_type;
  78   bfd_vma value;
  79
  80   if (**strp == '#')
  81     ++*strp;
  82
  83   if (strncasecmp (*strp, "high(", 5) == 0)
  84     {
  85       *strp += 5;
  86       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_M32R_HI16_ULO,
  87                                    & result_type, & value);
  88       if (**strp != ')')
  89         return MISSING_CLOSING_PARENTHESIS;
  90       ++*strp;
  91       if (errmsg == NULL
  92           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
  93         {
  94           value >>= 16;
  95           value &= 0xffff;
  96         }
  97       *valuep = value;
  98       return errmsg;
  99     }
 100   else if (strncasecmp (*strp, "shigh(", 6) == 0)
 101     {
 102       *strp += 6;
 103       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_M32R_HI16_SLO,
 104                                    & result_type, & value);
 105       if (**strp != ')')
 106         return MISSING_CLOSING_PARENTHESIS;
 107       ++*strp;
 108       if (errmsg == NULL
 109           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 110         {
 111           value += 0x8000;
 112           value >>= 16;
 113           value &= 0xffff;
 114         }
 115       *valuep = value;
 116       return errmsg;
 117     }
 118
 119   return cgen_parse_unsigned_integer (cd, strp, opindex, valuep);
 120 }
 121
 122 /* Handle low() in a signed context.  Also handle sda().
 123    The signedness of the value doesn't matter to low(), but this also
 124    handles the case where low() isn't present.  */
 125
 126 static const char *
 127 parse_slo16 (CGEN_CPU_DESC cd,
 128              const char ** strp,
 129              int opindex,
 130              long * valuep)
 131 {
 132   const char *errmsg;
 133   enum cgen_parse_operand_result result_type;
 134   bfd_vma value;
 135
 136   if (**strp == '#')
 137     ++*strp;
 138
 139   if (strncasecmp (*strp, "low(", 4) == 0)
 140     {
 141       *strp += 4;
 142       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_M32R_LO16,
 143                                    & result_type, & value);
 144       if (**strp != ')')
 145         return MISSING_CLOSING_PARENTHESIS;
 146       ++*strp;
 147       if (errmsg == NULL
 148           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 149         value = ((value & 0xffff) ^ 0x8000) - 0x8000;
 150       *valuep = value;
 151       return errmsg;
 152     }
 153
 154   if (strncasecmp (*strp, "sda(", 4) == 0)
 155     {
 156       *strp += 4;
 157       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_M32R_SDA16,
 158                                    NULL, & value);
 159       if (**strp != ')')
 160         return MISSING_CLOSING_PARENTHESIS;
 161       ++*strp;
 162       *valuep = value;
 163       return errmsg;
 164     }
 165
 166   return cgen_parse_signed_integer (cd, strp, opindex, valuep);
 167 }
 168
 169 /* Handle low() in an unsigned context.
 170    The signedness of the value doesn't matter to low(), but this also
 171    handles the case where low() isn't present.  */
 172
 173 static const char *
 174 parse_ulo16 (CGEN_CPU_DESC cd,
 175              const char **strp,
 176              int opindex,
 177              unsigned long *valuep)
 178 {
 179   const char *errmsg;
 180   enum cgen_parse_operand_result result_type;
 181   bfd_vma value;
 182
 183   if (**strp == '#')
 184     ++*strp;
 185
 186   if (strncasecmp (*strp, "low(", 4) == 0)
 187     {
 188       *strp += 4;
 189       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_M32R_LO16,
 190                                    & result_type, & value);
 191       if (**strp != ')')
 192         return MISSING_CLOSING_PARENTHESIS;
 193       ++*strp;
 194       if (errmsg == NULL
 195           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 196         value &= 0xffff;
 197       *valuep = value;
 198       return errmsg;
 199     }
 200
 201   return cgen_parse_unsigned_integer (cd, strp, opindex, valuep);
 202 }
 203
 204 /* -- */
 205
 206 const char * m32r_cgen_parse_operand
 207   (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);
 208
 209 /* Main entry point for operand parsing.
 210
 211    This function is basically just a big switch statement.  Earlier versions
 212    used tables to look up the function to use, but
 213    - if the table contains both assembler and disassembler functions then
 214      the disassembler contains much of the assembler and vice-versa,
 215    - there's a lot of inlining possibilities as things grow,
 216    - using a switch statement avoids the function call overhead.
 217
 218    This function could be moved into `parse_insn_normal', but keeping it
 219    separate makes clear the interface between `parse_insn_normal' and each of
 220    the handlers.  */
 221
 222 const char *
 223 m32r_cgen_parse_operand (CGEN_CPU_DESC cd,
 224                            int opindex,
 225                            const char ** strp,
 226                            CGEN_FIELDS * fields)
 227 {
 228   const char * errmsg = NULL;
 229   /* Used by scalar operands that still need to be parsed.  */
 230   long junk ATTRIBUTE_UNUSED;
 231
 232   switch (opindex)
 233     {
 234     case M32R_OPERAND_ACC :
 235       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_h_accums, & fields->f_acc);
 236       break;
 237     case M32R_OPERAND_ACCD :
 238       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_h_accums, & fields->f_accd);
 239       break;
 240     case M32R_OPERAND_ACCS :
 241       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_h_accums, & fields->f_accs);
 242       break;
 243     case M32R_OPERAND_DCR :
 244       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_cr_names, & fields->f_r1);
 245       break;
 246     case M32R_OPERAND_DISP16 :
 247       {
 248         bfd_vma value = 0;
 249         errmsg = cgen_parse_address (cd, strp, M32R_OPERAND_DISP16, 0, NULL,  & value);
 250         fields->f_disp16 = value;
 251       }
 252       break;
 253     case M32R_OPERAND_DISP24 :
 254       {
 255         bfd_vma value = 0;
 256         errmsg = cgen_parse_address (cd, strp, M32R_OPERAND_DISP24, 0, NULL,  & value);
 257         fields->f_disp24 = value;
 258       }
 259       break;
 260     case M32R_OPERAND_DISP8 :
 261       {
 262         bfd_vma value = 0;
 263         errmsg = cgen_parse_address (cd, strp, M32R_OPERAND_DISP8, 0, NULL,  & value);
 264         fields->f_disp8 = value;
 265       }
 266       break;
 267     case M32R_OPERAND_DR :
 268       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_gr_names, & fields->f_r1);
 269       break;
 270     case M32R_OPERAND_HASH :
 271       errmsg = parse_hash (cd, strp, M32R_OPERAND_HASH, (long *) (& junk));
 272       break;
 273     case M32R_OPERAND_HI16 :
 274       errmsg = parse_hi16 (cd, strp, M32R_OPERAND_HI16, (unsigned long *) (& fields->f_hi16));
 275       break;
 276     case M32R_OPERAND_IMM1 :
 277       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_IMM1, (unsigned long *) (& fields->f_imm1));
 278       break;
 279     case M32R_OPERAND_SCR :
 280       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_cr_names, & fields->f_r2);
 281       break;
 282     case M32R_OPERAND_SIMM16 :
 283       errmsg = cgen_parse_signed_integer (cd, strp, M32R_OPERAND_SIMM16, (long *) (& fields->f_simm16));
 284       break;
 285     case M32R_OPERAND_SIMM8 :
 286       errmsg = cgen_parse_signed_integer (cd, strp, M32R_OPERAND_SIMM8, (long *) (& fields->f_simm8));
 287       break;
 288     case M32R_OPERAND_SLO16 :
 289       errmsg = parse_slo16 (cd, strp, M32R_OPERAND_SLO16, (long *) (& fields->f_simm16));
 290       break;
 291     case M32R_OPERAND_SR :
 292       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_gr_names, & fields->f_r2);
 293       break;
 294     case M32R_OPERAND_SRC1 :
 295       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_gr_names, & fields->f_r1);
 296       break;
 297     case M32R_OPERAND_SRC2 :
 298       errmsg = cgen_parse_keyword (cd, strp, & m32r_cgen_opval_gr_names, & fields->f_r2);
 299       break;
 300     case M32R_OPERAND_UIMM16 :
 301       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_UIMM16, (unsigned long *) (& fields->f_uimm16));
 302       break;
 303     case M32R_OPERAND_UIMM24 :
 304       {
 305         bfd_vma value = 0;
 306         errmsg = cgen_parse_address (cd, strp, M32R_OPERAND_UIMM24, 0, NULL,  & value);
 307         fields->f_uimm24 = value;
 308       }
 309       break;
 310     case M32R_OPERAND_UIMM3 :
 311       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_UIMM3, (unsigned long *) (& fields->f_uimm3));
 312       break;
 313     case M32R_OPERAND_UIMM4 :
 314       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_UIMM4, (unsigned long *) (& fields->f_uimm4));
 315       break;
 316     case M32R_OPERAND_UIMM5 :
 317       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_UIMM5, (unsigned long *) (& fields->f_uimm5));
 318       break;
 319     case M32R_OPERAND_UIMM8 :
 320       errmsg = cgen_parse_unsigned_integer (cd, strp, M32R_OPERAND_UIMM8, (unsigned long *) (& fields->f_uimm8));
 321       break;
 322     case M32R_OPERAND_ULO16 :
 323       errmsg = parse_ulo16 (cd, strp, M32R_OPERAND_ULO16, (unsigned long *) (& fields->f_uimm16));
 324       break;
 325
 326     default :
 327       /* xgettext:c-format */
 328       fprintf (stderr, _("Unrecognized field %d while parsing.\n"), opindex);
 329       abort ();
 330   }
 331
 332   return errmsg;
 333 }
 334
 335 cgen_parse_fn * const m32r_cgen_parse_handlers[] =
 336 {
 337   parse_insn_normal,
 338 };
 339
 340 void
 341 m32r_cgen_init_asm (CGEN_CPU_DESC cd)
 342 {
 343   m32r_cgen_init_opcode_table (cd);
 344   m32r_cgen_init_ibld_table (cd);
 345   cd->parse_handlers = & m32r_cgen_parse_handlers[0];
 346   cd->parse_operand = m32r_cgen_parse_operand;
 347 #ifdef CGEN_ASM_INIT_HOOK
 348 CGEN_ASM_INIT_HOOK
 349 #endif
 350 }
 351
 352 \f
 353
 354 /* Regex construction routine.
 355
 356    This translates an opcode syntax string into a regex string,
 357    by replacing any non-character syntax element (such as an
 358    opcode) with the pattern '.*'
 359
 360    It then compiles the regex and stores it in the opcode, for
 361    later use by m32r_cgen_assemble_insn
 362
 363    Returns NULL for success, an error message for failure.  */
 364
 365 char *
 366 m32r_cgen_build_insn_regex (CGEN_INSN *insn)
 367 {
 368   CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
 369   const char *mnem = CGEN_INSN_MNEMONIC (insn);
 370   char rxbuf[CGEN_MAX_RX_ELEMENTS];
 371   char *rx = rxbuf;
 372   const CGEN_SYNTAX_CHAR_TYPE *syn;
 373   int reg_err;
 374
 375   syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));
 376
 377   /* Mnemonics come first in the syntax string.  */
 378   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 379     return _("missing mnemonic in syntax string");
 380   ++syn;
 381
 382   /* Generate a case sensitive regular expression that emulates case
 383      insensitive matching in the "C" locale.  We cannot generate a case
 384      insensitive regular expression because in Turkish locales, 'i' and 'I'
 385      are not equal modulo case conversion.  */
 386
 387   /* Copy the literal mnemonic out of the insn.  */
 388   for (; *mnem; mnem++)
 389     {
 390       char c = *mnem;
 391
 392       if (ISALPHA (c))
 393         {
 394           *rx++ = '[';
 395           *rx++ = TOLOWER (c);
 396           *rx++ = TOUPPER (c);
 397           *rx++ = ']';
 398         }
 399       else
 400         *rx++ = c;
 401     }
 402
 403   /* Copy any remaining literals from the syntax string into the rx.  */
 404   for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
 405     {
 406       if (CGEN_SYNTAX_CHAR_P (* syn))
 407         {
 408           char c = CGEN_SYNTAX_CHAR (* syn);
 409
 410           switch (c)
 411             {
 412               /* Escape any regex metacharacters in the syntax.  */
 413             case '.': case '[': case '\\':
 414             case '*': case '^': case '$':
 415
 416 #ifdef CGEN_ESCAPE_EXTENDED_REGEX
 417             case '?': case '{': case '}':
 418             case '(': case ')': case '*':
 419             case '|': case '+': case ']':
 420 #endif
 421               *rx++ = '\\';
 422               *rx++ = c;
 423               break;
 424
 425             default:
 426               if (ISALPHA (c))
 427                 {
 428                   *rx++ = '[';
 429                   *rx++ = TOLOWER (c);
 430                   *rx++ = TOUPPER (c);
 431                   *rx++ = ']';
 432                 }
 433               else
 434                 *rx++ = c;
 435               break;
 436             }
 437         }
 438       else
 439         {
 440           /* Replace non-syntax fields with globs.  */
 441           *rx++ = '.';
 442           *rx++ = '*';
 443         }
 444     }
 445
 446   /* Trailing whitespace ok.  */
 447   * rx++ = '[';
 448   * rx++ = ' ';
 449   * rx++ = '\t';
 450   * rx++ = ']';
 451   * rx++ = '*';
 452
 453   /* But anchor it after that.  */
 454   * rx++ = '$';
 455   * rx = '\0';
 456
 457   CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
 458   reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);
 459
 460   if (reg_err == 0)
 461     return NULL;
 462   else
 463     {
 464       static char msg[80];
 465
 466       regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
 467       regfree ((regex_t *) CGEN_INSN_RX (insn));
 468       free (CGEN_INSN_RX (insn));
 469       (CGEN_INSN_RX (insn)) = NULL;
 470       return msg;
 471     }
 472 }
 473
 474 \f
 475 /* Default insn parser.
 476
 477    The syntax string is scanned and operands are parsed and stored in FIELDS.
 478    Relocs are queued as we go via other callbacks.
 479
 480    ??? Note that this is currently an all-or-nothing parser.  If we fail to
 481    parse the instruction, we return 0 and the caller will start over from
 482    the beginning.  Backtracking will be necessary in parsing subexpressions,
 483    but that can be handled there.  Not handling backtracking here may get
 484    expensive in the case of the m68k.  Deal with later.
 485
 486    Returns NULL for success, an error message for failure.  */
 487
 488 static const char *
 489 parse_insn_normal (CGEN_CPU_DESC cd,
 490                    const CGEN_INSN *insn,
 491                    const char **strp,
 492                    CGEN_FIELDS *fields)
 493 {
 494   /* ??? Runtime added insns not handled yet.  */
 495   const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
 496   const char *str = *strp;
 497   const char *errmsg;
 498   const char *p;
 499   const CGEN_SYNTAX_CHAR_TYPE * syn;
 500 #ifdef CGEN_MNEMONIC_OPERANDS
 501   /* FIXME: wip */
 502   int past_opcode_p;
 503 #endif
 504
 505   /* For now we assume the mnemonic is first (there are no leading operands).
 506      We can parse it without needing to set up operand parsing.
 507      GAS's input scrubber will ensure mnemonics are lowercase, but we may
 508      not be called from GAS.  */
 509   p = CGEN_INSN_MNEMONIC (insn);
 510   while (*p && TOLOWER (*p) == TOLOWER (*str))
 511     ++p, ++str;
 512
 513   if (* p)
 514     return _("unrecognized instruction");
 515
 516 #ifndef CGEN_MNEMONIC_OPERANDS
 517   if (* str && ! ISSPACE (* str))
 518     return _("unrecognized instruction");
 519 #endif
 520
 521   CGEN_INIT_PARSE (cd);
 522   cgen_init_parse_operand (cd);
 523 #ifdef CGEN_MNEMONIC_OPERANDS
 524   past_opcode_p = 0;
 525 #endif
 526
 527   /* We don't check for (*str != '\0') here because we want to parse
 528      any trailing fake arguments in the syntax string.  */
 529   syn = CGEN_SYNTAX_STRING (syntax);
 530
 531   /* Mnemonics come first for now, ensure valid string.  */
 532   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 533     abort ();
 534
 535   ++syn;
 536
 537   while (* syn != 0)
 538     {
 539       /* Non operand chars must match exactly.  */
 540       if (CGEN_SYNTAX_CHAR_P (* syn))
 541         {
 542           /* FIXME: While we allow for non-GAS callers above, we assume the
 543              first char after the mnemonic part is a space.  */
 544           /* FIXME: We also take inappropriate advantage of the fact that
 545              GAS's input scrubber will remove extraneous blanks.  */
 546           if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
 547             {
 548 #ifdef CGEN_MNEMONIC_OPERANDS
 549               if (CGEN_SYNTAX_CHAR(* syn) == ' ')
 550                 past_opcode_p = 1;
 551 #endif
 552               ++ syn;
 553               ++ str;
 554             }
 555           else if (*str)
 556             {
 557               /* Syntax char didn't match.  Can't be this insn.  */
 558               static char msg [80];
 559
 560               /* xgettext:c-format */
 561               sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
 562                        CGEN_SYNTAX_CHAR(*syn), *str);
 563               return msg;
 564             }
 565           else
 566             {
 567               /* Ran out of input.  */
 568               static char msg [80];
 569
 570               /* xgettext:c-format */
 571               sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
 572                        CGEN_SYNTAX_CHAR(*syn));
 573               return msg;
 574             }
 575           continue;
 576         }
 577
 578       /* We have an operand of some sort.  */
 579       errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn),
 580                                           &str, fields);
 581       if (errmsg)
 582         return errmsg;
 583
 584       /* Done with this operand, continue with next one.  */
 585       ++ syn;
 586     }
 587
 588   /* If we're at the end of the syntax string, we're done.  */
 589   if (* syn == 0)
 590     {
 591       /* FIXME: For the moment we assume a valid `str' can only contain
 592          blanks now.  IE: We needn't try again with a longer version of
 593          the insn and it is assumed that longer versions of insns appear
 594          before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
 595       while (ISSPACE (* str))
 596         ++ str;
 597
 598       if (* str != '\0')
 599         return _("junk at end of line"); /* FIXME: would like to include `str' */
 600
 601       return NULL;
 602     }
 603
 604   /* We couldn't parse it.  */
 605   return _("unrecognized instruction");
 606 }
 607 \f
 608 /* Main entry point.
 609    This routine is called for each instruction to be assembled.
 610    STR points to the insn to be assembled.
 611    We assume all necessary tables have been initialized.
 612    The assembled instruction, less any fixups, is stored in BUF.
 613    Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
 614    still needs to be converted to target byte order, otherwise BUF is an array
 615    of bytes in target byte order.
 616    The result is a pointer to the insn's entry in the opcode table,
 617    or NULL if an error occured (an error message will have already been
 618    printed).
 619
 620    Note that when processing (non-alias) macro-insns,
 621    this function recurses.
 622
 623    ??? It's possible to make this cpu-independent.
 624    One would have to deal with a few minor things.
 625    At this point in time doing so would be more of a curiosity than useful
 626    [for example this file isn't _that_ big], but keeping the possibility in
 627    mind helps keep the design clean.  */
 628
 629 const CGEN_INSN *
 630 m32r_cgen_assemble_insn (CGEN_CPU_DESC cd,
 631                            const char *str,
 632                            CGEN_FIELDS *fields,
 633                            CGEN_INSN_BYTES_PTR buf,
 634                            char **errmsg)
 635 {
 636   const char *start;
 637   CGEN_INSN_LIST *ilist;
 638   const char *parse_errmsg = NULL;
 639   const char *insert_errmsg = NULL;
 640   int recognized_mnemonic = 0;
 641
 642   /* Skip leading white space.  */
 643   while (ISSPACE (* str))
 644     ++ str;
 645
 646   /* The instructions are stored in hashed lists.
 647      Get the first in the list.  */
 648   ilist = CGEN_ASM_LOOKUP_INSN (cd, str);
 649
 650   /* Keep looking until we find a match.  */
 651   start = str;
 652   for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
 653     {
 654       const CGEN_INSN *insn = ilist->insn;
 655       recognized_mnemonic = 1;
 656
 657 #ifdef CGEN_VALIDATE_INSN_SUPPORTED
 658       /* Not usually needed as unsupported opcodes
 659          shouldn't be in the hash lists.  */
 660       /* Is this insn supported by the selected cpu?  */
 661       if (! m32r_cgen_insn_supported (cd, insn))
 662         continue;
 663 #endif
 664       /* If the RELAXED attribute is set, this is an insn that shouldn't be
 665          chosen immediately.  Instead, it is used during assembler/linker
 666          relaxation if possible.  */
 667       if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
 668         continue;
 669
 670       str = start;
 671
 672       /* Skip this insn if str doesn't look right lexically.  */
 673       if (CGEN_INSN_RX (insn) != NULL &&
 674           regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
 675         continue;
 676
 677       /* Allow parse/insert handlers to obtain length of insn.  */
 678       CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);
 679
 680       parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
 681       if (parse_errmsg != NULL)
 682         continue;
 683
 684       /* ??? 0 is passed for `pc'.  */
 685       insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
 686                                                  (bfd_vma) 0);
 687       if (insert_errmsg != NULL)
 688         continue;
 689
 690       /* It is up to the caller to actually output the insn and any
 691          queued relocs.  */
 692       return insn;
 693     }
 694
 695   {
 696     static char errbuf[150];
 697 #ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
 698     const char *tmp_errmsg;
 699
 700     /* If requesting verbose error messages, use insert_errmsg.
 701        Failing that, use parse_errmsg.  */
 702     tmp_errmsg = (insert_errmsg ? insert_errmsg :
 703                   parse_errmsg ? parse_errmsg :
 704                   recognized_mnemonic ?
 705                   _("unrecognized form of instruction") :
 706                   _("unrecognized instruction"));
 707
 708     if (strlen (start) > 50)
 709       /* xgettext:c-format */
 710       sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
 711     else
 712       /* xgettext:c-format */
 713       sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
 714 #else
 715     if (strlen (start) > 50)
 716       /* xgettext:c-format */
 717       sprintf (errbuf, _("bad instruction `%.50s...'"), start);
 718     else
 719       /* xgettext:c-format */
 720       sprintf (errbuf, _("bad instruction `%.50s'"), start);
 721 #endif
 722
 723     *errmsg = errbuf;
 724     return NULL;
 725   }
 726 }