opcodes/lm32-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, 2008
   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 "lm32-desc.h"
  36 #include "lm32-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
  54 /* Handle signed/unsigned literal.  */
  55
  56 static const char *
  57 parse_imm (CGEN_CPU_DESC cd,
  58            const char **strp,
  59            int opindex,
  60            unsigned long *valuep)
  61 {
  62   const char *errmsg;
  63   signed long value;
  64
  65   errmsg = cgen_parse_signed_integer (cd, strp, opindex, & value);
  66   if (errmsg == NULL)
  67     {
  68       unsigned long x = value & 0xFFFF0000;
  69       if (x != 0 && x != 0xFFFF0000)
  70         errmsg = _("immediate value out of range");
  71       else
  72         *valuep = (value & 0xFFFF);
  73     }
  74   return errmsg;
  75 }
  76
  77 /* Handle hi() */
  78
  79 static const char *
  80 parse_hi16 (CGEN_CPU_DESC cd,
  81             const char **strp,
  82             int opindex,
  83             unsigned long *valuep)
  84 {
  85   if (strncasecmp (*strp, "hi(", 3) == 0)
  86     {
  87       enum cgen_parse_operand_result result_type;
  88       bfd_vma value;
  89       const char *errmsg;
  90
  91       *strp += 3;
  92       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_HI16,
  93                                    &result_type, &value);
  94       if (**strp != ')')
  95         return _("missing `)'");
  96
  97       ++*strp;
  98       if (errmsg == NULL
  99           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 100         value = (value >> 16) & 0xffff;
 101       *valuep = value;
 102
 103       return errmsg;
 104     }
 105
 106   return parse_imm (cd, strp, opindex, valuep);
 107 }
 108
 109 /* Handle lo() */
 110
 111 static const char *
 112 parse_lo16 (CGEN_CPU_DESC cd,
 113             const char **strp,
 114             int opindex,
 115             unsigned long *valuep)
 116 {
 117   if (strncasecmp (*strp, "lo(", 3) == 0)
 118     {
 119       const char *errmsg;
 120       enum cgen_parse_operand_result result_type;
 121       bfd_vma value;
 122
 123       *strp += 3;
 124       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LO16,
 125                                    &result_type, &value);
 126       if (**strp != ')')
 127         return _("missing `)'");
 128       ++*strp;
 129       if (errmsg == NULL
 130           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 131         value &= 0xffff;
 132       *valuep = value;
 133       return errmsg;
 134     }
 135
 136   return parse_imm (cd, strp, opindex, valuep);
 137 }
 138
 139 /* Handle gp() */
 140
 141 static const char *
 142 parse_gp16 (CGEN_CPU_DESC cd,
 143             const char **strp,
 144             int opindex,
 145             long *valuep)
 146 {
 147   if (strncasecmp (*strp, "gp(", 3) == 0)
 148     {
 149       const char *errmsg;
 150       enum cgen_parse_operand_result result_type;
 151       bfd_vma value;
 152
 153       *strp += 3;
 154       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_GPREL16,
 155                                    & result_type, & value);
 156       if (**strp != ')')
 157         return _("missing `)'");
 158       ++*strp;
 159       if (errmsg == NULL
 160           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 161         value &= 0xffff;
 162       *valuep = value;
 163       return errmsg;
 164     }
 165
 166   return _("expecting gp relative address: gp(symbol)");
 167 }
 168
 169 /* Handle got() */
 170
 171 static const char *
 172 parse_got16 (CGEN_CPU_DESC cd,
 173              const char **strp,
 174              int opindex,
 175              long *valuep)
 176 {
 177   if (strncasecmp (*strp, "got(", 4) == 0)
 178     {
 179       const char *errmsg;
 180       enum cgen_parse_operand_result result_type;
 181       bfd_vma value;
 182
 183       *strp += 4;
 184       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LM32_16_GOT,
 185                                    & result_type, & value);
 186       if (**strp != ')')
 187         return _("missing `)'");
 188       ++*strp;
 189       if (errmsg == NULL
 190           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 191         value &= 0xffff;
 192       *valuep = value;
 193       return errmsg;
 194     }
 195
 196   return _("expecting got relative address: got(symbol)");
 197 }
 198
 199 /* Handle gotoffhi16() */
 200
 201 static const char *
 202 parse_gotoff_hi16 (CGEN_CPU_DESC cd,
 203                    const char **strp,
 204                    int opindex,
 205                    long *valuep)
 206 {
 207   if (strncasecmp (*strp, "gotoffhi16(", 11) == 0)
 208     {
 209       const char *errmsg;
 210       enum cgen_parse_operand_result result_type;
 211       bfd_vma value;
 212
 213       *strp += 11;
 214       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LM32_GOTOFF_HI16,
 215                                    & result_type, & value);
 216       if (**strp != ')')
 217         return _("missing `)'");
 218       ++*strp;
 219       if (errmsg == NULL
 220           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 221         value &= 0xffff;
 222       *valuep = value;
 223       return errmsg;
 224     }
 225
 226   return _("expecting got relative address: gotoffhi16(symbol)");
 227 }
 228
 229 /* Handle gotofflo16() */
 230
 231 static const char *
 232 parse_gotoff_lo16 (CGEN_CPU_DESC cd,
 233                    const char **strp,
 234                    int opindex,
 235                    long *valuep)
 236 {
 237   if (strncasecmp (*strp, "gotofflo16(", 11) == 0)
 238     {
 239       const char *errmsg;
 240       enum cgen_parse_operand_result result_type;
 241       bfd_vma value;
 242
 243       *strp += 11;
 244       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LM32_GOTOFF_LO16,
 245                                    &result_type, &value);
 246       if (**strp != ')')
 247         return _("missing `)'");
 248       ++*strp;
 249       if (errmsg == NULL
 250           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 251         value &= 0xffff;
 252       *valuep = value;
 253       return errmsg;
 254     }
 255
 256   return _("expecting got relative address: gotofflo16(symbol)");
 257 }
 258
 259 const char * lm32_cgen_parse_operand
 260   (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);
 261
 262 /* Main entry point for operand parsing.
 263
 264    This function is basically just a big switch statement.  Earlier versions
 265    used tables to look up the function to use, but
 266    - if the table contains both assembler and disassembler functions then
 267      the disassembler contains much of the assembler and vice-versa,
 268    - there's a lot of inlining possibilities as things grow,
 269    - using a switch statement avoids the function call overhead.
 270
 271    This function could be moved into `parse_insn_normal', but keeping it
 272    separate makes clear the interface between `parse_insn_normal' and each of
 273    the handlers.  */
 274
 275 const char *
 276 lm32_cgen_parse_operand (CGEN_CPU_DESC cd,
 277                            int opindex,
 278                            const char ** strp,
 279                            CGEN_FIELDS * fields)
 280 {
 281   const char * errmsg = NULL;
 282   /* Used by scalar operands that still need to be parsed.  */
 283   long junk ATTRIBUTE_UNUSED;
 284
 285   switch (opindex)
 286     {
 287     case LM32_OPERAND_BRANCH :
 288       {
 289         bfd_vma value = 0;
 290         errmsg = cgen_parse_address (cd, strp, LM32_OPERAND_BRANCH, 0, NULL,  & value);
 291         fields->f_branch = value;
 292       }
 293       break;
 294     case LM32_OPERAND_CALL :
 295       {
 296         bfd_vma value = 0;
 297         errmsg = cgen_parse_address (cd, strp, LM32_OPERAND_CALL, 0, NULL,  & value);
 298         fields->f_call = value;
 299       }
 300       break;
 301     case LM32_OPERAND_CSR :
 302       errmsg = cgen_parse_keyword (cd, strp, & lm32_cgen_opval_h_csr, & fields->f_csr);
 303       break;
 304     case LM32_OPERAND_EXCEPTION :
 305       errmsg = cgen_parse_unsigned_integer (cd, strp, LM32_OPERAND_EXCEPTION, (unsigned long *) (& fields->f_exception));
 306       break;
 307     case LM32_OPERAND_GOT16 :
 308       errmsg = parse_got16 (cd, strp, LM32_OPERAND_GOT16, (long *) (& fields->f_imm));
 309       break;
 310     case LM32_OPERAND_GOTOFFHI16 :
 311       errmsg = parse_gotoff_hi16 (cd, strp, LM32_OPERAND_GOTOFFHI16, (long *) (& fields->f_imm));
 312       break;
 313     case LM32_OPERAND_GOTOFFLO16 :
 314       errmsg = parse_gotoff_lo16 (cd, strp, LM32_OPERAND_GOTOFFLO16, (long *) (& fields->f_imm));
 315       break;
 316     case LM32_OPERAND_GP16 :
 317       errmsg = parse_gp16 (cd, strp, LM32_OPERAND_GP16, (long *) (& fields->f_imm));
 318       break;
 319     case LM32_OPERAND_HI16 :
 320       errmsg = parse_hi16 (cd, strp, LM32_OPERAND_HI16, (unsigned long *) (& fields->f_uimm));
 321       break;
 322     case LM32_OPERAND_IMM :
 323       errmsg = cgen_parse_signed_integer (cd, strp, LM32_OPERAND_IMM, (long *) (& fields->f_imm));
 324       break;
 325     case LM32_OPERAND_LO16 :
 326       errmsg = parse_lo16 (cd, strp, LM32_OPERAND_LO16, (unsigned long *) (& fields->f_uimm));
 327       break;
 328     case LM32_OPERAND_R0 :
 329       errmsg = cgen_parse_keyword (cd, strp, & lm32_cgen_opval_h_gr, & fields->f_r0);
 330       break;
 331     case LM32_OPERAND_R1 :
 332       errmsg = cgen_parse_keyword (cd, strp, & lm32_cgen_opval_h_gr, & fields->f_r1);
 333       break;
 334     case LM32_OPERAND_R2 :
 335       errmsg = cgen_parse_keyword (cd, strp, & lm32_cgen_opval_h_gr, & fields->f_r2);
 336       break;
 337     case LM32_OPERAND_SHIFT :
 338       errmsg = cgen_parse_unsigned_integer (cd, strp, LM32_OPERAND_SHIFT, (unsigned long *) (& fields->f_shift));
 339       break;
 340     case LM32_OPERAND_UIMM :
 341       errmsg = cgen_parse_unsigned_integer (cd, strp, LM32_OPERAND_UIMM, (unsigned long *) (& fields->f_uimm));
 342       break;
 343     case LM32_OPERAND_USER :
 344       errmsg = cgen_parse_unsigned_integer (cd, strp, LM32_OPERAND_USER, (unsigned long *) (& fields->f_user));
 345       break;
 346
 347     default :
 348       /* xgettext:c-format */
 349       fprintf (stderr, _("Unrecognized field %d while parsing.\n"), opindex);
 350       abort ();
 351   }
 352
 353   return errmsg;
 354 }
 355
 356 cgen_parse_fn * const lm32_cgen_parse_handlers[] =
 357 {
 358   parse_insn_normal,
 359 };
 360
 361 void
 362 lm32_cgen_init_asm (CGEN_CPU_DESC cd)
 363 {
 364   lm32_cgen_init_opcode_table (cd);
 365   lm32_cgen_init_ibld_table (cd);
 366   cd->parse_handlers = & lm32_cgen_parse_handlers[0];
 367   cd->parse_operand = lm32_cgen_parse_operand;
 368 #ifdef CGEN_ASM_INIT_HOOK
 369 CGEN_ASM_INIT_HOOK
 370 #endif
 371 }
 372
 373 \f
 374
 375 /* Regex construction routine.
 376
 377    This translates an opcode syntax string into a regex string,
 378    by replacing any non-character syntax element (such as an
 379    opcode) with the pattern '.*'
 380
 381    It then compiles the regex and stores it in the opcode, for
 382    later use by lm32_cgen_assemble_insn
 383
 384    Returns NULL for success, an error message for failure.  */
 385
 386 char *
 387 lm32_cgen_build_insn_regex (CGEN_INSN *insn)
 388 {
 389   CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
 390   const char *mnem = CGEN_INSN_MNEMONIC (insn);
 391   char rxbuf[CGEN_MAX_RX_ELEMENTS];
 392   char *rx = rxbuf;
 393   const CGEN_SYNTAX_CHAR_TYPE *syn;
 394   int reg_err;
 395
 396   syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));
 397
 398   /* Mnemonics come first in the syntax string.  */
 399   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 400     return _("missing mnemonic in syntax string");
 401   ++syn;
 402
 403   /* Generate a case sensitive regular expression that emulates case
 404      insensitive matching in the "C" locale.  We cannot generate a case
 405      insensitive regular expression because in Turkish locales, 'i' and 'I'
 406      are not equal modulo case conversion.  */
 407
 408   /* Copy the literal mnemonic out of the insn.  */
 409   for (; *mnem; mnem++)
 410     {
 411       char c = *mnem;
 412
 413       if (ISALPHA (c))
 414         {
 415           *rx++ = '[';
 416           *rx++ = TOLOWER (c);
 417           *rx++ = TOUPPER (c);
 418           *rx++ = ']';
 419         }
 420       else
 421         *rx++ = c;
 422     }
 423
 424   /* Copy any remaining literals from the syntax string into the rx.  */
 425   for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
 426     {
 427       if (CGEN_SYNTAX_CHAR_P (* syn))
 428         {
 429           char c = CGEN_SYNTAX_CHAR (* syn);
 430
 431           switch (c)
 432             {
 433               /* Escape any regex metacharacters in the syntax.  */
 434             case '.': case '[': case '\\':
 435             case '*': case '^': case '$':
 436
 437 #ifdef CGEN_ESCAPE_EXTENDED_REGEX
 438             case '?': case '{': case '}':
 439             case '(': case ')': case '*':
 440             case '|': case '+': case ']':
 441 #endif
 442               *rx++ = '\\';
 443               *rx++ = c;
 444               break;
 445
 446             default:
 447               if (ISALPHA (c))
 448                 {
 449                   *rx++ = '[';
 450                   *rx++ = TOLOWER (c);
 451                   *rx++ = TOUPPER (c);
 452                   *rx++ = ']';
 453                 }
 454               else
 455                 *rx++ = c;
 456               break;
 457             }
 458         }
 459       else
 460         {
 461           /* Replace non-syntax fields with globs.  */
 462           *rx++ = '.';
 463           *rx++ = '*';
 464         }
 465     }
 466
 467   /* Trailing whitespace ok.  */
 468   * rx++ = '[';
 469   * rx++ = ' ';
 470   * rx++ = '\t';
 471   * rx++ = ']';
 472   * rx++ = '*';
 473
 474   /* But anchor it after that.  */
 475   * rx++ = '$';
 476   * rx = '\0';
 477
 478   CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
 479   reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);
 480
 481   if (reg_err == 0)
 482     return NULL;
 483   else
 484     {
 485       static char msg[80];
 486
 487       regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
 488       regfree ((regex_t *) CGEN_INSN_RX (insn));
 489       free (CGEN_INSN_RX (insn));
 490       (CGEN_INSN_RX (insn)) = NULL;
 491       return msg;
 492     }
 493 }
 494
 495 \f
 496 /* Default insn parser.
 497
 498    The syntax string is scanned and operands are parsed and stored in FIELDS.
 499    Relocs are queued as we go via other callbacks.
 500
 501    ??? Note that this is currently an all-or-nothing parser.  If we fail to
 502    parse the instruction, we return 0 and the caller will start over from
 503    the beginning.  Backtracking will be necessary in parsing subexpressions,
 504    but that can be handled there.  Not handling backtracking here may get
 505    expensive in the case of the m68k.  Deal with later.
 506
 507    Returns NULL for success, an error message for failure.  */
 508
 509 static const char *
 510 parse_insn_normal (CGEN_CPU_DESC cd,
 511                    const CGEN_INSN *insn,
 512                    const char **strp,
 513                    CGEN_FIELDS *fields)
 514 {
 515   /* ??? Runtime added insns not handled yet.  */
 516   const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
 517   const char *str = *strp;
 518   const char *errmsg;
 519   const char *p;
 520   const CGEN_SYNTAX_CHAR_TYPE * syn;
 521 #ifdef CGEN_MNEMONIC_OPERANDS
 522   /* FIXME: wip */
 523   int past_opcode_p;
 524 #endif
 525
 526   /* For now we assume the mnemonic is first (there are no leading operands).
 527      We can parse it without needing to set up operand parsing.
 528      GAS's input scrubber will ensure mnemonics are lowercase, but we may
 529      not be called from GAS.  */
 530   p = CGEN_INSN_MNEMONIC (insn);
 531   while (*p && TOLOWER (*p) == TOLOWER (*str))
 532     ++p, ++str;
 533
 534   if (* p)
 535     return _("unrecognized instruction");
 536
 537 #ifndef CGEN_MNEMONIC_OPERANDS
 538   if (* str && ! ISSPACE (* str))
 539     return _("unrecognized instruction");
 540 #endif
 541
 542   CGEN_INIT_PARSE (cd);
 543   cgen_init_parse_operand (cd);
 544 #ifdef CGEN_MNEMONIC_OPERANDS
 545   past_opcode_p = 0;
 546 #endif
 547
 548   /* We don't check for (*str != '\0') here because we want to parse
 549      any trailing fake arguments in the syntax string.  */
 550   syn = CGEN_SYNTAX_STRING (syntax);
 551
 552   /* Mnemonics come first for now, ensure valid string.  */
 553   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 554     abort ();
 555
 556   ++syn;
 557
 558   while (* syn != 0)
 559     {
 560       /* Non operand chars must match exactly.  */
 561       if (CGEN_SYNTAX_CHAR_P (* syn))
 562         {
 563           /* FIXME: While we allow for non-GAS callers above, we assume the
 564              first char after the mnemonic part is a space.  */
 565           /* FIXME: We also take inappropriate advantage of the fact that
 566              GAS's input scrubber will remove extraneous blanks.  */
 567           if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
 568             {
 569 #ifdef CGEN_MNEMONIC_OPERANDS
 570               if (CGEN_SYNTAX_CHAR(* syn) == ' ')
 571                 past_opcode_p = 1;
 572 #endif
 573               ++ syn;
 574               ++ str;
 575             }
 576           else if (*str)
 577             {
 578               /* Syntax char didn't match.  Can't be this insn.  */
 579               static char msg [80];
 580
 581               /* xgettext:c-format */
 582               sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
 583                        CGEN_SYNTAX_CHAR(*syn), *str);
 584               return msg;
 585             }
 586           else
 587             {
 588               /* Ran out of input.  */
 589               static char msg [80];
 590
 591               /* xgettext:c-format */
 592               sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
 593                        CGEN_SYNTAX_CHAR(*syn));
 594               return msg;
 595             }
 596           continue;
 597         }
 598
 599       /* We have an operand of some sort.  */
 600       errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn),
 601                                           &str, fields);
 602       if (errmsg)
 603         return errmsg;
 604
 605       /* Done with this operand, continue with next one.  */
 606       ++ syn;
 607     }
 608
 609   /* If we're at the end of the syntax string, we're done.  */
 610   if (* syn == 0)
 611     {
 612       /* FIXME: For the moment we assume a valid `str' can only contain
 613          blanks now.  IE: We needn't try again with a longer version of
 614          the insn and it is assumed that longer versions of insns appear
 615          before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
 616       while (ISSPACE (* str))
 617         ++ str;
 618
 619       if (* str != '\0')
 620         return _("junk at end of line"); /* FIXME: would like to include `str' */
 621
 622       return NULL;
 623     }
 624
 625   /* We couldn't parse it.  */
 626   return _("unrecognized instruction");
 627 }
 628 \f
 629 /* Main entry point.
 630    This routine is called for each instruction to be assembled.
 631    STR points to the insn to be assembled.
 632    We assume all necessary tables have been initialized.
 633    The assembled instruction, less any fixups, is stored in BUF.
 634    Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
 635    still needs to be converted to target byte order, otherwise BUF is an array
 636    of bytes in target byte order.
 637    The result is a pointer to the insn's entry in the opcode table,
 638    or NULL if an error occured (an error message will have already been
 639    printed).
 640
 641    Note that when processing (non-alias) macro-insns,
 642    this function recurses.
 643
 644    ??? It's possible to make this cpu-independent.
 645    One would have to deal with a few minor things.
 646    At this point in time doing so would be more of a curiosity than useful
 647    [for example this file isn't _that_ big], but keeping the possibility in
 648    mind helps keep the design clean.  */
 649
 650 const CGEN_INSN *
 651 lm32_cgen_assemble_insn (CGEN_CPU_DESC cd,
 652                            const char *str,
 653                            CGEN_FIELDS *fields,
 654                            CGEN_INSN_BYTES_PTR buf,
 655                            char **errmsg)
 656 {
 657   const char *start;
 658   CGEN_INSN_LIST *ilist;
 659   const char *parse_errmsg = NULL;
 660   const char *insert_errmsg = NULL;
 661   int recognized_mnemonic = 0;
 662
 663   /* Skip leading white space.  */
 664   while (ISSPACE (* str))
 665     ++ str;
 666
 667   /* The instructions are stored in hashed lists.
 668      Get the first in the list.  */
 669   ilist = CGEN_ASM_LOOKUP_INSN (cd, str);
 670
 671   /* Keep looking until we find a match.  */
 672   start = str;
 673   for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
 674     {
 675       const CGEN_INSN *insn = ilist->insn;
 676       recognized_mnemonic = 1;
 677
 678 #ifdef CGEN_VALIDATE_INSN_SUPPORTED
 679       /* Not usually needed as unsupported opcodes
 680          shouldn't be in the hash lists.  */
 681       /* Is this insn supported by the selected cpu?  */
 682       if (! lm32_cgen_insn_supported (cd, insn))
 683         continue;
 684 #endif
 685       /* If the RELAXED attribute is set, this is an insn that shouldn't be
 686          chosen immediately.  Instead, it is used during assembler/linker
 687          relaxation if possible.  */
 688       if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
 689         continue;
 690
 691       str = start;
 692
 693       /* Skip this insn if str doesn't look right lexically.  */
 694       if (CGEN_INSN_RX (insn) != NULL &&
 695           regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
 696         continue;
 697
 698       /* Allow parse/insert handlers to obtain length of insn.  */
 699       CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);
 700
 701       parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
 702       if (parse_errmsg != NULL)
 703         continue;
 704
 705       /* ??? 0 is passed for `pc'.  */
 706       insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
 707                                                  (bfd_vma) 0);
 708       if (insert_errmsg != NULL)
 709         continue;
 710
 711       /* It is up to the caller to actually output the insn and any
 712          queued relocs.  */
 713       return insn;
 714     }
 715
 716   {
 717     static char errbuf[150];
 718 #ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
 719     const char *tmp_errmsg;
 720
 721     /* If requesting verbose error messages, use insert_errmsg.
 722        Failing that, use parse_errmsg.  */
 723     tmp_errmsg = (insert_errmsg ? insert_errmsg :
 724                   parse_errmsg ? parse_errmsg :
 725                   recognized_mnemonic ?
 726                   _("unrecognized form of instruction") :
 727                   _("unrecognized instruction"));
 728
 729     if (strlen (start) > 50)
 730       /* xgettext:c-format */
 731       sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
 732     else
 733       /* xgettext:c-format */
 734       sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
 735 #else
 736     if (strlen (start) > 50)
 737       /* xgettext:c-format */
 738       sprintf (errbuf, _("bad instruction `%.50s...'"), start);
 739     else
 740       /* xgettext:c-format */
 741       sprintf (errbuf, _("bad instruction `%.50s'"), start);
 742 #endif
 743
 744     *errmsg = errbuf;
 745     return NULL;
 746   }
 747 }