opcodes/iq2000-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 "iq2000-desc.h"
  36 #include "iq2000-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 #include "safe-ctype.h"
  55
  56 static const char * MISSING_CLOSING_PARENTHESIS = N_("missing `)'");
  57
  58 /* Special check to ensure that instruction exists for given machine.  */
  59
  60 int
  61 iq2000_cgen_insn_supported (CGEN_CPU_DESC cd, const CGEN_INSN *insn)
  62 {
  63   int machs = cd->machs;
  64
  65   return (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_MACH) & machs) != 0;
  66 }
  67
  68 static int
  69 iq2000_cgen_isa_register (const char **strp)
  70 {
  71   int len;
  72   int ch1, ch2;
  73
  74   if (**strp == 'r' || **strp == 'R')
  75     {
  76       len = strlen (*strp);
  77       if (len == 2)
  78         {
  79           ch1 = (*strp)[1];
  80           if ('0' <= ch1 && ch1 <= '9')
  81             return 1;
  82         }
  83       else if (len == 3)
  84         {
  85           ch1 = (*strp)[1];
  86           ch2 = (*strp)[2];
  87           if (('1' <= ch1 && ch1 <= '2') && ('0' <= ch2 && ch2 <= '9'))
  88             return 1;
  89           if ('3' == ch1 && (ch2 == '0' || ch2 == '1'))
  90             return 1;
  91         }
  92     }
  93   if (**strp == '%'
  94       && TOLOWER ((*strp)[1]) != 'l'
  95       && TOLOWER ((*strp)[1]) != 'h')
  96     return 1;
  97   return 0;
  98 }
  99
 100 /* Handle negated literal.  */
 101
 102 static const char *
 103 parse_mimm (CGEN_CPU_DESC cd,
 104             const char **strp,
 105             int opindex,
 106             unsigned long *valuep)
 107 {
 108   const char *errmsg;
 109
 110   /* Verify this isn't a register.  */
 111   if (iq2000_cgen_isa_register (strp))
 112     errmsg = _("immediate value cannot be register");
 113   else
 114     {
 115       long value;
 116
 117       errmsg = cgen_parse_signed_integer (cd, strp, opindex, & value);
 118       if (errmsg == NULL)
 119         {
 120           long x = (-value) & 0xFFFF0000;
 121
 122           if (x != 0 && x != (long) 0xFFFF0000)
 123             errmsg = _("immediate value out of range");
 124           else
 125             *valuep = (-value & 0xFFFF);
 126         }
 127     }
 128   return errmsg;
 129 }
 130
 131 /* Handle signed/unsigned literal.  */
 132
 133 static const char *
 134 parse_imm (CGEN_CPU_DESC cd,
 135            const char **strp,
 136            int opindex,
 137            unsigned long *valuep)
 138 {
 139   const char *errmsg;
 140
 141   if (iq2000_cgen_isa_register (strp))
 142     errmsg = _("immediate value cannot be register");
 143   else
 144     {
 145       long value;
 146
 147       errmsg = cgen_parse_signed_integer (cd, strp, opindex, & value);
 148       if (errmsg == NULL)
 149         {
 150           long x = value & 0xFFFF0000;
 151
 152           if (x != 0 && x != (long) 0xFFFF0000)
 153             errmsg = _("immediate value out of range");
 154           else
 155             *valuep = (value & 0xFFFF);
 156         }
 157     }
 158   return errmsg;
 159 }
 160
 161 /* Handle iq10 21-bit jmp offset.  */
 162
 163 static const char *
 164 parse_jtargq10 (CGEN_CPU_DESC cd,
 165                 const char **strp,
 166                 int opindex,
 167                 int reloc ATTRIBUTE_UNUSED,
 168                 enum cgen_parse_operand_result *type_addr ATTRIBUTE_UNUSED,
 169                 bfd_vma *valuep)
 170 {
 171   const char *errmsg;
 172   bfd_vma value;
 173   enum cgen_parse_operand_result result_type = CGEN_PARSE_OPERAND_RESULT_NUMBER;
 174
 175   errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_IQ2000_OFFSET_21,
 176                                & result_type, & value);
 177   if (errmsg == NULL && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 178     {
 179       /* Check value is within 23-bits
 180          (remembering that 2-bit shift right will occur).  */
 181       if (value > 0x7fffff)
 182         return _("21-bit offset out of range");
 183     }
 184   *valuep = (value & 0x7FFFFF);
 185   return errmsg;
 186 }
 187
 188 /* Handle high().  */
 189
 190 static const char *
 191 parse_hi16 (CGEN_CPU_DESC cd,
 192             const char **strp,
 193             int opindex,
 194             unsigned long *valuep)
 195 {
 196   if (strncasecmp (*strp, "%hi(", 4) == 0)
 197     {
 198       enum cgen_parse_operand_result result_type;
 199       bfd_vma value;
 200       const char *errmsg;
 201
 202       *strp += 4;
 203       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_HI16,
 204                                    & result_type, & value);
 205       if (**strp != ')')
 206         return MISSING_CLOSING_PARENTHESIS;
 207
 208       ++*strp;
 209       if (errmsg == NULL
 210           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 211         {
 212           /* If value has top-bit of %lo on, then it will
 213              sign-propagate and so we compensate by adding
 214              1 to the resultant %hi value.  */
 215           if (value & 0x8000)
 216             value += 0x10000;
 217           value >>= 16;
 218           value &= 0xffff;
 219         }
 220       *valuep = value;
 221
 222       return errmsg;
 223     }
 224
 225   /* We add %uhi in case a user just wants the high 16-bits or is using
 226      an insn like ori for %lo which does not sign-propagate.  */
 227   if (strncasecmp (*strp, "%uhi(", 5) == 0)
 228     {
 229       enum cgen_parse_operand_result result_type;
 230       bfd_vma value;
 231       const char *errmsg;
 232
 233       *strp += 5;
 234       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_IQ2000_UHI16,
 235                                    & result_type, & value);
 236       if (**strp != ')')
 237         return MISSING_CLOSING_PARENTHESIS;
 238
 239       ++*strp;
 240       if (errmsg == NULL
 241           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 242         value >>= 16;
 243
 244       value &= 0xffff;
 245       *valuep = value;
 246
 247       return errmsg;
 248     }
 249
 250   return parse_imm (cd, strp, opindex, valuep);
 251 }
 252
 253 /* Handle %lo in a signed context.
 254    The signedness of the value doesn't matter to %lo(), but this also
 255    handles the case where %lo() isn't present.  */
 256
 257 static const char *
 258 parse_lo16 (CGEN_CPU_DESC cd,
 259             const char **strp,
 260             int opindex,
 261             unsigned long *valuep)
 262 {
 263   if (strncasecmp (*strp, "%lo(", 4) == 0)
 264     {
 265       const char *errmsg;
 266       enum cgen_parse_operand_result result_type;
 267       bfd_vma value;
 268
 269       *strp += 4;
 270       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LO16,
 271                                    & result_type, & value);
 272       if (**strp != ')')
 273         return MISSING_CLOSING_PARENTHESIS;
 274       ++*strp;
 275       if (errmsg == NULL
 276           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 277         value &= 0xffff;
 278       *valuep = value;
 279       return errmsg;
 280     }
 281
 282   return parse_imm (cd, strp, opindex, valuep);
 283 }
 284
 285 /* Handle %lo in a negated signed context.
 286    The signedness of the value doesn't matter to %lo(), but this also
 287    handles the case where %lo() isn't present.  */
 288
 289 static const char *
 290 parse_mlo16 (CGEN_CPU_DESC cd,
 291              const char **strp,
 292              int opindex,
 293              unsigned long *valuep)
 294 {
 295   if (strncasecmp (*strp, "%lo(", 4) == 0)
 296     {
 297       const char *errmsg;
 298       enum cgen_parse_operand_result result_type;
 299       bfd_vma value;
 300
 301       *strp += 4;
 302       errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_LO16,
 303                                    & result_type, & value);
 304       if (**strp != ')')
 305         return MISSING_CLOSING_PARENTHESIS;
 306       ++*strp;
 307       if (errmsg == NULL
 308           && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
 309         value = (-value) & 0xffff;
 310       *valuep = value;
 311       return errmsg;
 312     }
 313
 314   return parse_mimm (cd, strp, opindex, valuep);
 315 }
 316
 317 /* -- */
 318
 319 const char * iq2000_cgen_parse_operand
 320   (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);
 321
 322 /* Main entry point for operand parsing.
 323
 324    This function is basically just a big switch statement.  Earlier versions
 325    used tables to look up the function to use, but
 326    - if the table contains both assembler and disassembler functions then
 327      the disassembler contains much of the assembler and vice-versa,
 328    - there's a lot of inlining possibilities as things grow,
 329    - using a switch statement avoids the function call overhead.
 330
 331    This function could be moved into `parse_insn_normal', but keeping it
 332    separate makes clear the interface between `parse_insn_normal' and each of
 333    the handlers.  */
 334
 335 const char *
 336 iq2000_cgen_parse_operand (CGEN_CPU_DESC cd,
 337                            int opindex,
 338                            const char ** strp,
 339                            CGEN_FIELDS * fields)
 340 {
 341   const char * errmsg = NULL;
 342   /* Used by scalar operands that still need to be parsed.  */
 343   long junk ATTRIBUTE_UNUSED;
 344
 345   switch (opindex)
 346     {
 347     case IQ2000_OPERAND__INDEX :
 348       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND__INDEX, (unsigned long *) (& fields->f_index));
 349       break;
 350     case IQ2000_OPERAND_BASE :
 351       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rs);
 352       break;
 353     case IQ2000_OPERAND_BASEOFF :
 354       {
 355         bfd_vma value = 0;
 356         errmsg = cgen_parse_address (cd, strp, IQ2000_OPERAND_BASEOFF, 0, NULL,  & value);
 357         fields->f_imm = value;
 358       }
 359       break;
 360     case IQ2000_OPERAND_BITNUM :
 361       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_BITNUM, (unsigned long *) (& fields->f_rt));
 362       break;
 363     case IQ2000_OPERAND_BYTECOUNT :
 364       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_BYTECOUNT, (unsigned long *) (& fields->f_bytecount));
 365       break;
 366     case IQ2000_OPERAND_CAM_Y :
 367       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CAM_Y, (unsigned long *) (& fields->f_cam_y));
 368       break;
 369     case IQ2000_OPERAND_CAM_Z :
 370       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CAM_Z, (unsigned long *) (& fields->f_cam_z));
 371       break;
 372     case IQ2000_OPERAND_CM_3FUNC :
 373       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CM_3FUNC, (unsigned long *) (& fields->f_cm_3func));
 374       break;
 375     case IQ2000_OPERAND_CM_3Z :
 376       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CM_3Z, (unsigned long *) (& fields->f_cm_3z));
 377       break;
 378     case IQ2000_OPERAND_CM_4FUNC :
 379       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CM_4FUNC, (unsigned long *) (& fields->f_cm_4func));
 380       break;
 381     case IQ2000_OPERAND_CM_4Z :
 382       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_CM_4Z, (unsigned long *) (& fields->f_cm_4z));
 383       break;
 384     case IQ2000_OPERAND_COUNT :
 385       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_COUNT, (unsigned long *) (& fields->f_count));
 386       break;
 387     case IQ2000_OPERAND_EXECODE :
 388       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_EXECODE, (unsigned long *) (& fields->f_excode));
 389       break;
 390     case IQ2000_OPERAND_HI16 :
 391       errmsg = parse_hi16 (cd, strp, IQ2000_OPERAND_HI16, (unsigned long *) (& fields->f_imm));
 392       break;
 393     case IQ2000_OPERAND_IMM :
 394       errmsg = parse_imm (cd, strp, IQ2000_OPERAND_IMM, (unsigned long *) (& fields->f_imm));
 395       break;
 396     case IQ2000_OPERAND_JMPTARG :
 397       {
 398         bfd_vma value = 0;
 399         errmsg = cgen_parse_address (cd, strp, IQ2000_OPERAND_JMPTARG, 0, NULL,  & value);
 400         fields->f_jtarg = value;
 401       }
 402       break;
 403     case IQ2000_OPERAND_JMPTARGQ10 :
 404       {
 405         bfd_vma value = 0;
 406         errmsg = parse_jtargq10 (cd, strp, IQ2000_OPERAND_JMPTARGQ10, 0, NULL,  & value);
 407         fields->f_jtargq10 = value;
 408       }
 409       break;
 410     case IQ2000_OPERAND_LO16 :
 411       errmsg = parse_lo16 (cd, strp, IQ2000_OPERAND_LO16, (unsigned long *) (& fields->f_imm));
 412       break;
 413     case IQ2000_OPERAND_MASK :
 414       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_MASK, (unsigned long *) (& fields->f_mask));
 415       break;
 416     case IQ2000_OPERAND_MASKL :
 417       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_MASKL, (unsigned long *) (& fields->f_maskl));
 418       break;
 419     case IQ2000_OPERAND_MASKQ10 :
 420       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_MASKQ10, (unsigned long *) (& fields->f_maskq10));
 421       break;
 422     case IQ2000_OPERAND_MASKR :
 423       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_MASKR, (unsigned long *) (& fields->f_rs));
 424       break;
 425     case IQ2000_OPERAND_MLO16 :
 426       errmsg = parse_mlo16 (cd, strp, IQ2000_OPERAND_MLO16, (unsigned long *) (& fields->f_imm));
 427       break;
 428     case IQ2000_OPERAND_OFFSET :
 429       {
 430         bfd_vma value = 0;
 431         errmsg = cgen_parse_address (cd, strp, IQ2000_OPERAND_OFFSET, 0, NULL,  & value);
 432         fields->f_offset = value;
 433       }
 434       break;
 435     case IQ2000_OPERAND_RD :
 436       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rd);
 437       break;
 438     case IQ2000_OPERAND_RD_RS :
 439       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rd_rs);
 440       break;
 441     case IQ2000_OPERAND_RD_RT :
 442       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rd_rt);
 443       break;
 444     case IQ2000_OPERAND_RS :
 445       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rs);
 446       break;
 447     case IQ2000_OPERAND_RT :
 448       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rt);
 449       break;
 450     case IQ2000_OPERAND_RT_RS :
 451       errmsg = cgen_parse_keyword (cd, strp, & iq2000_cgen_opval_gr_names, & fields->f_rt_rs);
 452       break;
 453     case IQ2000_OPERAND_SHAMT :
 454       errmsg = cgen_parse_unsigned_integer (cd, strp, IQ2000_OPERAND_SHAMT, (unsigned long *) (& fields->f_shamt));
 455       break;
 456
 457     default :
 458       /* xgettext:c-format */
 459       fprintf (stderr, _("Unrecognized field %d while parsing.\n"), opindex);
 460       abort ();
 461   }
 462
 463   return errmsg;
 464 }
 465
 466 cgen_parse_fn * const iq2000_cgen_parse_handlers[] =
 467 {
 468   parse_insn_normal,
 469 };
 470
 471 void
 472 iq2000_cgen_init_asm (CGEN_CPU_DESC cd)
 473 {
 474   iq2000_cgen_init_opcode_table (cd);
 475   iq2000_cgen_init_ibld_table (cd);
 476   cd->parse_handlers = & iq2000_cgen_parse_handlers[0];
 477   cd->parse_operand = iq2000_cgen_parse_operand;
 478 #ifdef CGEN_ASM_INIT_HOOK
 479 CGEN_ASM_INIT_HOOK
 480 #endif
 481 }
 482
 483 \f
 484
 485 /* Regex construction routine.
 486
 487    This translates an opcode syntax string into a regex string,
 488    by replacing any non-character syntax element (such as an
 489    opcode) with the pattern '.*'
 490
 491    It then compiles the regex and stores it in the opcode, for
 492    later use by iq2000_cgen_assemble_insn
 493
 494    Returns NULL for success, an error message for failure.  */
 495
 496 char *
 497 iq2000_cgen_build_insn_regex (CGEN_INSN *insn)
 498 {
 499   CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
 500   const char *mnem = CGEN_INSN_MNEMONIC (insn);
 501   char rxbuf[CGEN_MAX_RX_ELEMENTS];
 502   char *rx = rxbuf;
 503   const CGEN_SYNTAX_CHAR_TYPE *syn;
 504   int reg_err;
 505
 506   syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));
 507
 508   /* Mnemonics come first in the syntax string.  */
 509   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 510     return _("missing mnemonic in syntax string");
 511   ++syn;
 512
 513   /* Generate a case sensitive regular expression that emulates case
 514      insensitive matching in the "C" locale.  We cannot generate a case
 515      insensitive regular expression because in Turkish locales, 'i' and 'I'
 516      are not equal modulo case conversion.  */
 517
 518   /* Copy the literal mnemonic out of the insn.  */
 519   for (; *mnem; mnem++)
 520     {
 521       char c = *mnem;
 522
 523       if (ISALPHA (c))
 524         {
 525           *rx++ = '[';
 526           *rx++ = TOLOWER (c);
 527           *rx++ = TOUPPER (c);
 528           *rx++ = ']';
 529         }
 530       else
 531         *rx++ = c;
 532     }
 533
 534   /* Copy any remaining literals from the syntax string into the rx.  */
 535   for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
 536     {
 537       if (CGEN_SYNTAX_CHAR_P (* syn))
 538         {
 539           char c = CGEN_SYNTAX_CHAR (* syn);
 540
 541           switch (c)
 542             {
 543               /* Escape any regex metacharacters in the syntax.  */
 544             case '.': case '[': case '\\':
 545             case '*': case '^': case '$':
 546
 547 #ifdef CGEN_ESCAPE_EXTENDED_REGEX
 548             case '?': case '{': case '}':
 549             case '(': case ')': case '*':
 550             case '|': case '+': case ']':
 551 #endif
 552               *rx++ = '\\';
 553               *rx++ = c;
 554               break;
 555
 556             default:
 557               if (ISALPHA (c))
 558                 {
 559                   *rx++ = '[';
 560                   *rx++ = TOLOWER (c);
 561                   *rx++ = TOUPPER (c);
 562                   *rx++ = ']';
 563                 }
 564               else
 565                 *rx++ = c;
 566               break;
 567             }
 568         }
 569       else
 570         {
 571           /* Replace non-syntax fields with globs.  */
 572           *rx++ = '.';
 573           *rx++ = '*';
 574         }
 575     }
 576
 577   /* Trailing whitespace ok.  */
 578   * rx++ = '[';
 579   * rx++ = ' ';
 580   * rx++ = '\t';
 581   * rx++ = ']';
 582   * rx++ = '*';
 583
 584   /* But anchor it after that.  */
 585   * rx++ = '$';
 586   * rx = '\0';
 587
 588   CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
 589   reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);
 590
 591   if (reg_err == 0)
 592     return NULL;
 593   else
 594     {
 595       static char msg[80];
 596
 597       regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
 598       regfree ((regex_t *) CGEN_INSN_RX (insn));
 599       free (CGEN_INSN_RX (insn));
 600       (CGEN_INSN_RX (insn)) = NULL;
 601       return msg;
 602     }
 603 }
 604
 605 \f
 606 /* Default insn parser.
 607
 608    The syntax string is scanned and operands are parsed and stored in FIELDS.
 609    Relocs are queued as we go via other callbacks.
 610
 611    ??? Note that this is currently an all-or-nothing parser.  If we fail to
 612    parse the instruction, we return 0 and the caller will start over from
 613    the beginning.  Backtracking will be necessary in parsing subexpressions,
 614    but that can be handled there.  Not handling backtracking here may get
 615    expensive in the case of the m68k.  Deal with later.
 616
 617    Returns NULL for success, an error message for failure.  */
 618
 619 static const char *
 620 parse_insn_normal (CGEN_CPU_DESC cd,
 621                    const CGEN_INSN *insn,
 622                    const char **strp,
 623                    CGEN_FIELDS *fields)
 624 {
 625   /* ??? Runtime added insns not handled yet.  */
 626   const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
 627   const char *str = *strp;
 628   const char *errmsg;
 629   const char *p;
 630   const CGEN_SYNTAX_CHAR_TYPE * syn;
 631 #ifdef CGEN_MNEMONIC_OPERANDS
 632   /* FIXME: wip */
 633   int past_opcode_p;
 634 #endif
 635
 636   /* For now we assume the mnemonic is first (there are no leading operands).
 637      We can parse it without needing to set up operand parsing.
 638      GAS's input scrubber will ensure mnemonics are lowercase, but we may
 639      not be called from GAS.  */
 640   p = CGEN_INSN_MNEMONIC (insn);
 641   while (*p && TOLOWER (*p) == TOLOWER (*str))
 642     ++p, ++str;
 643
 644   if (* p)
 645     return _("unrecognized instruction");
 646
 647 #ifndef CGEN_MNEMONIC_OPERANDS
 648   if (* str && ! ISSPACE (* str))
 649     return _("unrecognized instruction");
 650 #endif
 651
 652   CGEN_INIT_PARSE (cd);
 653   cgen_init_parse_operand (cd);
 654 #ifdef CGEN_MNEMONIC_OPERANDS
 655   past_opcode_p = 0;
 656 #endif
 657
 658   /* We don't check for (*str != '\0') here because we want to parse
 659      any trailing fake arguments in the syntax string.  */
 660   syn = CGEN_SYNTAX_STRING (syntax);
 661
 662   /* Mnemonics come first for now, ensure valid string.  */
 663   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 664     abort ();
 665
 666   ++syn;
 667
 668   while (* syn != 0)
 669     {
 670       /* Non operand chars must match exactly.  */
 671       if (CGEN_SYNTAX_CHAR_P (* syn))
 672         {
 673           /* FIXME: While we allow for non-GAS callers above, we assume the
 674              first char after the mnemonic part is a space.  */
 675           /* FIXME: We also take inappropriate advantage of the fact that
 676              GAS's input scrubber will remove extraneous blanks.  */
 677           if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
 678             {
 679 #ifdef CGEN_MNEMONIC_OPERANDS
 680               if (CGEN_SYNTAX_CHAR(* syn) == ' ')
 681                 past_opcode_p = 1;
 682 #endif
 683               ++ syn;
 684               ++ str;
 685             }
 686           else if (*str)
 687             {
 688               /* Syntax char didn't match.  Can't be this insn.  */
 689               static char msg [80];
 690
 691               /* xgettext:c-format */
 692               sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
 693                        CGEN_SYNTAX_CHAR(*syn), *str);
 694               return msg;
 695             }
 696           else
 697             {
 698               /* Ran out of input.  */
 699               static char msg [80];
 700
 701               /* xgettext:c-format */
 702               sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
 703                        CGEN_SYNTAX_CHAR(*syn));
 704               return msg;
 705             }
 706           continue;
 707         }
 708
 709       /* We have an operand of some sort.  */
 710       errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn),
 711                                           &str, fields);
 712       if (errmsg)
 713         return errmsg;
 714
 715       /* Done with this operand, continue with next one.  */
 716       ++ syn;
 717     }
 718
 719   /* If we're at the end of the syntax string, we're done.  */
 720   if (* syn == 0)
 721     {
 722       /* FIXME: For the moment we assume a valid `str' can only contain
 723          blanks now.  IE: We needn't try again with a longer version of
 724          the insn and it is assumed that longer versions of insns appear
 725          before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
 726       while (ISSPACE (* str))
 727         ++ str;
 728
 729       if (* str != '\0')
 730         return _("junk at end of line"); /* FIXME: would like to include `str' */
 731
 732       return NULL;
 733     }
 734
 735   /* We couldn't parse it.  */
 736   return _("unrecognized instruction");
 737 }
 738 \f
 739 /* Main entry point.
 740    This routine is called for each instruction to be assembled.
 741    STR points to the insn to be assembled.
 742    We assume all necessary tables have been initialized.
 743    The assembled instruction, less any fixups, is stored in BUF.
 744    Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
 745    still needs to be converted to target byte order, otherwise BUF is an array
 746    of bytes in target byte order.
 747    The result is a pointer to the insn's entry in the opcode table,
 748    or NULL if an error occured (an error message will have already been
 749    printed).
 750
 751    Note that when processing (non-alias) macro-insns,
 752    this function recurses.
 753
 754    ??? It's possible to make this cpu-independent.
 755    One would have to deal with a few minor things.
 756    At this point in time doing so would be more of a curiosity than useful
 757    [for example this file isn't _that_ big], but keeping the possibility in
 758    mind helps keep the design clean.  */
 759
 760 const CGEN_INSN *
 761 iq2000_cgen_assemble_insn (CGEN_CPU_DESC cd,
 762                            const char *str,
 763                            CGEN_FIELDS *fields,
 764                            CGEN_INSN_BYTES_PTR buf,
 765                            char **errmsg)
 766 {
 767   const char *start;
 768   CGEN_INSN_LIST *ilist;
 769   const char *parse_errmsg = NULL;
 770   const char *insert_errmsg = NULL;
 771   int recognized_mnemonic = 0;
 772
 773   /* Skip leading white space.  */
 774   while (ISSPACE (* str))
 775     ++ str;
 776
 777   /* The instructions are stored in hashed lists.
 778      Get the first in the list.  */
 779   ilist = CGEN_ASM_LOOKUP_INSN (cd, str);
 780
 781   /* Keep looking until we find a match.  */
 782   start = str;
 783   for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
 784     {
 785       const CGEN_INSN *insn = ilist->insn;
 786       recognized_mnemonic = 1;
 787
 788 #ifdef CGEN_VALIDATE_INSN_SUPPORTED
 789       /* Not usually needed as unsupported opcodes
 790          shouldn't be in the hash lists.  */
 791       /* Is this insn supported by the selected cpu?  */
 792       if (! iq2000_cgen_insn_supported (cd, insn))
 793         continue;
 794 #endif
 795       /* If the RELAXED attribute is set, this is an insn that shouldn't be
 796          chosen immediately.  Instead, it is used during assembler/linker
 797          relaxation if possible.  */
 798       if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
 799         continue;
 800
 801       str = start;
 802
 803       /* Skip this insn if str doesn't look right lexically.  */
 804       if (CGEN_INSN_RX (insn) != NULL &&
 805           regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
 806         continue;
 807
 808       /* Allow parse/insert handlers to obtain length of insn.  */
 809       CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);
 810
 811       parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
 812       if (parse_errmsg != NULL)
 813         continue;
 814
 815       /* ??? 0 is passed for `pc'.  */
 816       insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
 817                                                  (bfd_vma) 0);
 818       if (insert_errmsg != NULL)
 819         continue;
 820
 821       /* It is up to the caller to actually output the insn and any
 822          queued relocs.  */
 823       return insn;
 824     }
 825
 826   {
 827     static char errbuf[150];
 828 #ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
 829     const char *tmp_errmsg;
 830
 831     /* If requesting verbose error messages, use insert_errmsg.
 832        Failing that, use parse_errmsg.  */
 833     tmp_errmsg = (insert_errmsg ? insert_errmsg :
 834                   parse_errmsg ? parse_errmsg :
 835                   recognized_mnemonic ?
 836                   _("unrecognized form of instruction") :
 837                   _("unrecognized instruction"));
 838
 839     if (strlen (start) > 50)
 840       /* xgettext:c-format */
 841       sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
 842     else
 843       /* xgettext:c-format */
 844       sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
 845 #else
 846     if (strlen (start) > 50)
 847       /* xgettext:c-format */
 848       sprintf (errbuf, _("bad instruction `%.50s...'"), start);
 849     else
 850       /* xgettext:c-format */
 851       sprintf (errbuf, _("bad instruction `%.50s'"), start);
 852 #endif
 853
 854     *errmsg = errbuf;
 855     return NULL;
 856   }
 857 }