opcodes/arc-dis.c

   1 /* Instruction printing code for the ARC.
   2    Copyright 1994, 1995, 1997, 1998, 2000, 2001, 2002, 2005, 2007, 2009
   3    Free Software Foundation, Inc.
   4    Contributed by Doug Evans (dje@cygnus.com).
   5
   6    This file is part of libopcodes.
   7
   8    This library is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3, or (at your option)
  11    any later version.
  12
  13    It is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 #include "ansidecl.h"
  24 #include "libiberty.h"
  25 #include "dis-asm.h"
  26 #include "opcode/arc.h"
  27 #include "elf-bfd.h"
  28 #include "elf/arc.h"
  29 #include <string.h>
  30 #include "opintl.h"
  31
  32 #include <stdarg.h>
  33 #include "arc-dis.h"
  34 #include "arc-ext.h"
  35
  36 #ifndef dbg
  37 #define dbg (0)
  38 #endif
  39
  40 /* Classification of the opcodes for the decoder to print
  41    the instructions.  */
  42
  43 typedef enum
  44 {
  45   CLASS_A4_ARITH,
  46   CLASS_A4_OP3_GENERAL,
  47   CLASS_A4_FLAG,
  48   /* All branches other than JC.  */
  49   CLASS_A4_BRANCH,
  50   CLASS_A4_JC ,
  51   /* All loads other than immediate
  52      indexed loads.  */
  53   CLASS_A4_LD0,
  54   CLASS_A4_LD1,
  55   CLASS_A4_ST,
  56   CLASS_A4_SR,
  57   /* All single operand instructions.  */
  58   CLASS_A4_OP3_SUBOPC3F,
  59   CLASS_A4_LR
  60 } a4_decoding_class;
  61
  62 #define BIT(word,n)     ((word) & (1 << n))
  63 #define BITS(word,s,e)  (((word) << (31 - e)) >> (s + (31 - e)))
  64 #define OPCODE(word)    (BITS ((word), 27, 31))
  65 #define FIELDA(word)    (BITS ((word), 21, 26))
  66 #define FIELDB(word)    (BITS ((word), 15, 20))
  67 #define FIELDC(word)    (BITS ((word),  9, 14))
  68
  69 /* FIELD D is signed in all of its uses, so we make sure argument is
  70    treated as signed for bit shifting purposes:  */
  71 #define FIELDD(word)    (BITS (((signed int)word), 0, 8))
  72
  73 #define PUT_NEXT_WORD_IN(a)                                             \
  74   do                                                                    \
  75     {                                                                   \
  76       if (is_limm == 1 && !NEXT_WORD (1))                               \
  77         mwerror (state, _("Illegal limm reference in last instruction!\n")); \
  78       a = state->words[1];                                              \
  79     }                                                                   \
  80   while (0)
  81
  82 #define CHECK_FLAG_COND_NULLIFY()                               \
  83   do                                                            \
  84     {                                                           \
  85       if (is_shimm == 0)                                        \
  86         {                                                       \
  87           flag = BIT (state->words[0], 8);                      \
  88           state->nullifyMode = BITS (state->words[0], 5, 6);    \
  89           cond = BITS (state->words[0], 0, 4);                  \
  90         }                                                       \
  91     }                                                           \
  92   while (0)
  93
  94 #define CHECK_COND()                            \
  95   do                                            \
  96     {                                           \
  97       if (is_shimm == 0)                        \
  98         cond = BITS (state->words[0], 0, 4);    \
  99     }                                           \
 100   while (0)
 101
 102 #define CHECK_FIELD(field)                      \
 103   do                                            \
 104     {                                           \
 105       if (field == 62)                          \
 106         {                                       \
 107           is_limm++;                            \
 108           field##isReg = 0;                     \
 109           PUT_NEXT_WORD_IN (field);             \
 110           limm_value = field;                   \
 111         }                                       \
 112       else if (field > 60)                      \
 113         {                                       \
 114           field##isReg = 0;                     \
 115           is_shimm++;                           \
 116           flag = (field == 61);                 \
 117           field = FIELDD (state->words[0]);     \
 118         }                                       \
 119     }                                           \
 120   while (0)
 121
 122 #define CHECK_FIELD_A()                         \
 123   do                                            \
 124     {                                           \
 125       fieldA = FIELDA (state->words[0]);        \
 126       if (fieldA > 60)                          \
 127         {                                       \
 128           fieldAisReg = 0;                      \
 129           fieldA = 0;                           \
 130         }                                       \
 131     }                                           \
 132   while (0)
 133
 134 #define CHECK_FIELD_B()                         \
 135   do                                            \
 136     {                                           \
 137       fieldB = FIELDB (state->words[0]);        \
 138       CHECK_FIELD (fieldB);                     \
 139     }                                           \
 140   while (0)
 141
 142 #define CHECK_FIELD_C()                         \
 143   do                                            \
 144     {                                           \
 145       fieldC = FIELDC (state->words[0]);        \
 146       CHECK_FIELD (fieldC);                     \
 147     }                                           \
 148   while (0)
 149
 150 #define IS_SMALL(x)                 (((field##x) < 256) && ((field##x) > -257))
 151 #define IS_REG(x)                    (field##x##isReg)
 152 #define WRITE_FORMAT_LB_Rx_RB(x)     WRITE_FORMAT (x, "[","]","","")
 153 #define WRITE_FORMAT_x_COMMA_LB(x)   WRITE_FORMAT (x, "",",[","",",[")
 154 #define WRITE_FORMAT_COMMA_x_RB(x)   WRITE_FORMAT (x, ",","]",",","]")
 155 #define WRITE_FORMAT_x_RB(x)         WRITE_FORMAT (x, "","]","","]")
 156 #define WRITE_FORMAT_COMMA_x(x)      WRITE_FORMAT (x, ",","",",","")
 157 #define WRITE_FORMAT_x_COMMA(x)      WRITE_FORMAT (x, "",",","",",")
 158 #define WRITE_FORMAT_x(x)            WRITE_FORMAT (x, "","","","")
 159 #define WRITE_FORMAT(x,cb1,ca1,cb,ca) strcat (formatString,             \
 160                                      (IS_REG (x) ? cb1"%r"ca1 :         \
 161                                       usesAuxReg ? cb"%a"ca :           \
 162                                       IS_SMALL (x) ? cb"%d"ca : cb"%h"ca))
 163 #define WRITE_FORMAT_RB()       strcat (formatString, "]")
 164 #define WRITE_COMMENT(str)      (state->comm[state->commNum++] = (str))
 165 #define WRITE_NOP_COMMENT()     if (!fieldAisReg && !flag) WRITE_COMMENT ("nop");
 166
 167 #define NEXT_WORD(x)    (offset += 4, state->words[x])
 168
 169 #define add_target(x)   (state->targets[state->tcnt++] = (x))
 170
 171 static char comment_prefix[] = "\t; ";
 172
 173 static const char *
 174 core_reg_name (struct arcDisState * state, int val)
 175 {
 176   if (state->coreRegName)
 177     return (*state->coreRegName)(state->_this, val);
 178   return 0;
 179 }
 180
 181 static const char *
 182 aux_reg_name (struct arcDisState * state, int val)
 183 {
 184   if (state->auxRegName)
 185     return (*state->auxRegName)(state->_this, val);
 186   return 0;
 187 }
 188
 189 static const char *
 190 cond_code_name (struct arcDisState * state, int val)
 191 {
 192   if (state->condCodeName)
 193     return (*state->condCodeName)(state->_this, val);
 194   return 0;
 195 }
 196
 197 static const char *
 198 instruction_name (struct arcDisState * state,
 199                   int    op1,
 200                   int    op2,
 201                   int *  flags)
 202 {
 203   if (state->instName)
 204     return (*state->instName)(state->_this, op1, op2, flags);
 205   return 0;
 206 }
 207
 208 static void
 209 mwerror (struct arcDisState * state, const char * msg)
 210 {
 211   if (state->err != 0)
 212     (*state->err)(state->_this, (msg));
 213 }
 214
 215 static const char *
 216 post_address (struct arcDisState * state, int addr)
 217 {
 218   static char id[3 * ARRAY_SIZE (state->addresses)];
 219   int j, i = state->acnt;
 220
 221   if (i < ((int) ARRAY_SIZE (state->addresses)))
 222     {
 223       state->addresses[i] = addr;
 224       ++state->acnt;
 225       j = i*3;
 226       id[j+0] = '@';
 227       id[j+1] = '0'+i;
 228       id[j+2] = 0;
 229
 230       return id + j;
 231     }
 232   return "";
 233 }
 234
 235 static void
 236 arc_sprintf (struct arcDisState *state, char *buf, const char *format, ...)
 237 {
 238   char *bp;
 239   const char *p;
 240   int size, leading_zero, regMap[2];
 241   long auxNum;
 242   va_list ap;
 243
 244   va_start (ap, format);
 245
 246   bp = buf;
 247   *bp = 0;
 248   p = format;
 249   auxNum = -1;
 250   regMap[0] = 0;
 251   regMap[1] = 0;
 252
 253   while (1)
 254     switch (*p++)
 255       {
 256       case 0:
 257         goto DOCOMM; /* (return)  */
 258       default:
 259         *bp++ = p[-1];
 260         break;
 261       case '%':
 262         size = 0;
 263         leading_zero = 0;
 264       RETRY: ;
 265         switch (*p++)
 266           {
 267           case '0':
 268           case '1':
 269           case '2':
 270           case '3':
 271           case '4':
 272           case '5':
 273           case '6':
 274           case '7':
 275           case '8':
 276           case '9':
 277             {
 278               /* size.  */
 279               size = p[-1] - '0';
 280               if (size == 0)
 281                 leading_zero = 1; /* e.g. %08x  */
 282               while (*p >= '0' && *p <= '9')
 283                 {
 284                   size = size * 10 + *p - '0';
 285                   p++;
 286                 }
 287               goto RETRY;
 288             }
 289 #define inc_bp() bp = bp + strlen (bp)
 290
 291           case 'h':
 292             {
 293               unsigned u = va_arg (ap, int);
 294
 295               /* Hex.  We can change the format to 0x%08x in
 296                  one place, here, if we wish.
 297                  We add underscores for easy reading.  */
 298               if (u > 65536)
 299                 sprintf (bp, "0x%x_%04x", u >> 16, u & 0xffff);
 300               else
 301                 sprintf (bp, "0x%x", u);
 302               inc_bp ();
 303             }
 304             break;
 305           case 'X': case 'x':
 306             {
 307               int val = va_arg (ap, int);
 308
 309               if (size != 0)
 310                 if (leading_zero)
 311                   sprintf (bp, "%0*x", size, val);
 312                 else
 313                   sprintf (bp, "%*x", size, val);
 314               else
 315                 sprintf (bp, "%x", val);
 316               inc_bp ();
 317             }
 318             break;
 319           case 'd':
 320             {
 321               int val = va_arg (ap, int);
 322
 323               if (size != 0)
 324                 sprintf (bp, "%*d", size, val);
 325               else
 326                 sprintf (bp, "%d", val);
 327               inc_bp ();
 328             }
 329             break;
 330           case 'r':
 331             {
 332               /* Register.  */
 333               int val = va_arg (ap, int);
 334
 335 #define REG2NAME(num, name) case num: sprintf (bp, ""name); \
 336   regMap[(num < 32) ? 0 : 1] |= 1 << (num - ((num < 32) ? 0 : 32)); break;
 337
 338               switch (val)
 339                 {
 340                   REG2NAME (26, "gp");
 341                   REG2NAME (27, "fp");
 342                   REG2NAME (28, "sp");
 343                   REG2NAME (29, "ilink1");
 344                   REG2NAME (30, "ilink2");
 345                   REG2NAME (31, "blink");
 346                   REG2NAME (60, "lp_count");
 347                 default:
 348                   {
 349                     const char * ext;
 350
 351                     ext = core_reg_name (state, val);
 352                     if (ext)
 353                       sprintf (bp, "%s", ext);
 354                     else
 355                       sprintf (bp,"r%d",val);
 356                   }
 357                   break;
 358                 }
 359               inc_bp ();
 360             } break;
 361
 362           case 'a':
 363             {
 364               /* Aux Register.  */
 365               int val = va_arg (ap, int);
 366
 367 #define AUXREG2NAME(num, name) case num: sprintf (bp,name); break;
 368
 369               switch (val)
 370                 {
 371                   AUXREG2NAME (0x0, "status");
 372                   AUXREG2NAME (0x1, "semaphore");
 373                   AUXREG2NAME (0x2, "lp_start");
 374                   AUXREG2NAME (0x3, "lp_end");
 375                   AUXREG2NAME (0x4, "identity");
 376                   AUXREG2NAME (0x5, "debug");
 377                 default:
 378                   {
 379                     const char *ext;
 380
 381                     ext = aux_reg_name (state, val);
 382                     if (ext)
 383                       sprintf (bp, "%s", ext);
 384                     else
 385                       arc_sprintf (state, bp, "%h", val);
 386                   }
 387                   break;
 388                 }
 389               inc_bp ();
 390             }
 391             break;
 392
 393           case 's':
 394             {
 395               sprintf (bp, "%s", va_arg (ap, char *));
 396               inc_bp ();
 397             }
 398             break;
 399
 400           default:
 401             fprintf (stderr, "?? format %c\n", p[-1]);
 402             break;
 403           }
 404       }
 405
 406  DOCOMM: *bp = 0;
 407   va_end (ap);
 408 }
 409
 410 static void
 411 write_comments_(struct arcDisState * state,
 412                 int shimm,
 413                 int is_limm,
 414                 long limm_value)
 415 {
 416   if (state->commentBuffer != 0)
 417     {
 418       int i;
 419
 420       if (is_limm)
 421         {
 422           const char *name = post_address (state, limm_value + shimm);
 423
 424           if (*name != 0)
 425             WRITE_COMMENT (name);
 426         }
 427       for (i = 0; i < state->commNum; i++)
 428         {
 429           if (i == 0)
 430             strcpy (state->commentBuffer, comment_prefix);
 431           else
 432             strcat (state->commentBuffer, ", ");
 433           strncat (state->commentBuffer, state->comm[i],
 434                    sizeof (state->commentBuffer));
 435         }
 436     }
 437 }
 438
 439 #define write_comments2(x) write_comments_ (state, x, is_limm, limm_value)
 440 #define write_comments()   write_comments2 (0)
 441
 442 static const char *condName[] =
 443 {
 444   /* 0..15.  */
 445   ""   , "z"  , "nz" , "p"  , "n"  , "c"  , "nc" , "v"  ,
 446   "nv" , "gt" , "ge" , "lt" , "le" , "hi" , "ls" , "pnz"
 447 };
 448
 449 static void
 450 write_instr_name_(struct arcDisState * state,
 451                   const char * instrName,
 452                   int cond,
 453                   int condCodeIsPartOfName,
 454                   int flag,
 455                   int signExtend,
 456                   int addrWriteBack,
 457                   int directMem)
 458 {
 459   strcpy (state->instrBuffer, instrName);
 460
 461   if (cond > 0)
 462     {
 463       const char *cc = 0;
 464
 465       if (!condCodeIsPartOfName)
 466         strcat (state->instrBuffer, ".");
 467
 468       if (cond < 16)
 469         cc = condName[cond];
 470       else
 471         cc = cond_code_name (state, cond);
 472
 473       if (!cc)
 474         cc = "???";
 475
 476       strcat (state->instrBuffer, cc);
 477     }
 478
 479   if (flag)
 480     strcat (state->instrBuffer, ".f");
 481
 482   switch (state->nullifyMode)
 483     {
 484     case BR_exec_always:
 485       strcat (state->instrBuffer, ".d");
 486       break;
 487     case BR_exec_when_jump:
 488       strcat (state->instrBuffer, ".jd");
 489       break;
 490     }
 491
 492   if (signExtend)
 493     strcat (state->instrBuffer, ".x");
 494
 495   if (addrWriteBack)
 496     strcat (state->instrBuffer, ".a");
 497
 498   if (directMem)
 499     strcat (state->instrBuffer, ".di");
 500 }
 501
 502 #define write_instr_name()                                              \
 503   do                                                                    \
 504     {                                                                   \
 505       write_instr_name_(state, instrName,cond, condCodeIsPartOfName,    \
 506                         flag, signExtend, addrWriteBack, directMem);    \
 507       formatString[0] = '\0';                                           \
 508     }                                                                   \
 509   while (0)
 510
 511 enum
 512 {
 513   op_LD0 = 0, op_LD1 = 1, op_ST  = 2, op_3   = 3,
 514   op_BC  = 4, op_BLC = 5, op_LPC = 6, op_JC  = 7,
 515   op_ADD = 8, op_ADC = 9, op_SUB = 10, op_SBC = 11,
 516   op_AND = 12, op_OR  = 13, op_BIC = 14, op_XOR = 15
 517 };
 518
 519 extern disassemble_info tm_print_insn_info;
 520
 521 static int
 522 dsmOneArcInst (bfd_vma addr, struct arcDisState * state)
 523 {
 524   int condCodeIsPartOfName = 0;
 525   a4_decoding_class decodingClass;
 526   const char * instrName;
 527   int repeatsOp = 0;
 528   int fieldAisReg = 1;
 529   int fieldBisReg = 1;
 530   int fieldCisReg = 1;
 531   int fieldA;
 532   int fieldB;
 533   int fieldC = 0;
 534   int flag = 0;
 535   int cond = 0;
 536   int is_shimm = 0;
 537   int is_limm = 0;
 538   long limm_value = 0;
 539   int signExtend = 0;
 540   int addrWriteBack = 0;
 541   int directMem = 0;
 542   int is_linked = 0;
 543   int offset = 0;
 544   int usesAuxReg = 0;
 545   int flags;
 546   int ignoreFirstOpd;
 547   char formatString[60];
 548
 549   state->instructionLen = 4;
 550   state->nullifyMode = BR_exec_when_no_jump;
 551   state->opWidth = 12;
 552   state->isBranch = 0;
 553
 554   state->_mem_load = 0;
 555   state->_ea_present = 0;
 556   state->_load_len = 0;
 557   state->ea_reg1 = no_reg;
 558   state->ea_reg2 = no_reg;
 559   state->_offset = 0;
 560
 561   if (! NEXT_WORD (0))
 562     return 0;
 563
 564   state->_opcode = OPCODE (state->words[0]);
 565   instrName = 0;
 566   decodingClass = CLASS_A4_ARITH; /* default!  */
 567   repeatsOp = 0;
 568   condCodeIsPartOfName=0;
 569   state->commNum = 0;
 570   state->tcnt = 0;
 571   state->acnt = 0;
 572   state->flow = noflow;
 573   ignoreFirstOpd = 0;
 574
 575   if (state->commentBuffer)
 576     state->commentBuffer[0] = '\0';
 577
 578   switch (state->_opcode)
 579     {
 580     case op_LD0:
 581       switch (BITS (state->words[0],1,2))
 582         {
 583         case 0:
 584           instrName = "ld";
 585           state->_load_len = 4;
 586           break;
 587         case 1:
 588           instrName = "ldb";
 589           state->_load_len = 1;
 590           break;
 591         case 2:
 592           instrName = "ldw";
 593           state->_load_len = 2;
 594           break;
 595         default:
 596           instrName = "??? (0[3])";
 597           state->flow = invalid_instr;
 598           break;
 599         }
 600       decodingClass = CLASS_A4_LD0;
 601       break;
 602
 603     case op_LD1:
 604       if (BIT (state->words[0],13))
 605         {
 606           instrName = "lr";
 607           decodingClass = CLASS_A4_LR;
 608         }
 609       else
 610         {
 611           switch (BITS (state->words[0], 10, 11))
 612             {
 613             case 0:
 614               instrName = "ld";
 615               state->_load_len = 4;
 616               break;
 617             case 1:
 618               instrName = "ldb";
 619               state->_load_len = 1;
 620               break;
 621             case 2:
 622               instrName = "ldw";
 623               state->_load_len = 2;
 624               break;
 625             default:
 626               instrName = "??? (1[3])";
 627               state->flow = invalid_instr;
 628               break;
 629             }
 630           decodingClass = CLASS_A4_LD1;
 631         }
 632       break;
 633
 634     case op_ST:
 635       if (BIT (state->words[0], 25))
 636         {
 637           instrName = "sr";
 638           decodingClass = CLASS_A4_SR;
 639         }
 640       else
 641         {
 642           switch (BITS (state->words[0], 22, 23))
 643             {
 644             case 0:
 645               instrName = "st";
 646               break;
 647             case 1:
 648               instrName = "stb";
 649               break;
 650             case 2:
 651               instrName = "stw";
 652               break;
 653             default:
 654               instrName = "??? (2[3])";
 655               state->flow = invalid_instr;
 656               break;
 657             }
 658           decodingClass = CLASS_A4_ST;
 659         }
 660       break;
 661
 662     case op_3:
 663       decodingClass = CLASS_A4_OP3_GENERAL;  /* default for opcode 3...  */
 664       switch (FIELDC (state->words[0]))
 665         {
 666         case  0:
 667           instrName = "flag";
 668           decodingClass = CLASS_A4_FLAG;
 669           break;
 670         case  1:
 671           instrName = "asr";
 672           break;
 673         case  2:
 674           instrName = "lsr";
 675           break;
 676         case  3:
 677           instrName = "ror";
 678           break;
 679         case  4:
 680           instrName = "rrc";
 681           break;
 682         case  5:
 683           instrName = "sexb";
 684           break;
 685         case  6:
 686           instrName = "sexw";
 687           break;
 688         case  7:
 689           instrName = "extb";
 690           break;
 691         case  8:
 692           instrName = "extw";
 693           break;
 694         case  0x3f:
 695           {
 696             decodingClass = CLASS_A4_OP3_SUBOPC3F;
 697             switch (FIELDD (state->words[0]))
 698               {
 699               case 0:
 700                 instrName = "brk";
 701                 break;
 702               case 1:
 703                 instrName = "sleep";
 704                 break;
 705               case 2:
 706                 instrName = "swi";
 707                 break;
 708               default:
 709                 instrName = "???";
 710                 state->flow=invalid_instr;
 711                 break;
 712               }
 713           }
 714           break;
 715
 716           /* ARC Extension Library Instructions
 717              NOTE: We assume that extension codes are these instrs.  */
 718         default:
 719           instrName = instruction_name (state,
 720                                         state->_opcode,
 721                                         FIELDC (state->words[0]),
 722                                         &flags);
 723           if (!instrName)
 724             {
 725               instrName = "???";
 726               state->flow = invalid_instr;
 727             }
 728           if (flags & IGNORE_FIRST_OPD)
 729             ignoreFirstOpd = 1;
 730           break;
 731         }
 732       break;
 733
 734     case op_BC:
 735       instrName = "b";
 736     case op_BLC:
 737       if (!instrName)
 738         instrName = "bl";
 739     case op_LPC:
 740       if (!instrName)
 741         instrName = "lp";
 742     case op_JC:
 743       if (!instrName)
 744         {
 745           if (BITS (state->words[0],9,9))
 746             {
 747               instrName = "jl";
 748               is_linked = 1;
 749             }
 750           else
 751             {
 752               instrName = "j";
 753               is_linked = 0;
 754             }
 755         }
 756       condCodeIsPartOfName = 1;
 757       decodingClass = ((state->_opcode == op_JC) ? CLASS_A4_JC : CLASS_A4_BRANCH );
 758       state->isBranch = 1;
 759       break;
 760
 761     case op_ADD:
 762     case op_ADC:
 763     case op_AND:
 764       repeatsOp = (FIELDC (state->words[0]) == FIELDB (state->words[0]));
 765
 766       switch (state->_opcode)
 767         {
 768         case op_ADD:
 769           instrName = (repeatsOp ? "asl" : "add");
 770           break;
 771         case op_ADC:
 772           instrName = (repeatsOp ? "rlc" : "adc");
 773           break;
 774         case op_AND:
 775           instrName = (repeatsOp ? "mov" : "and");
 776           break;
 777         }
 778       break;
 779
 780     case op_SUB: instrName = "sub";
 781       break;
 782     case op_SBC: instrName = "sbc";
 783       break;
 784     case op_OR:  instrName = "or";
 785       break;
 786     case op_BIC: instrName = "bic";
 787       break;
 788
 789     case op_XOR:
 790       if (state->words[0] == 0x7fffffff)
 791         {
 792           /* NOP encoded as xor -1, -1, -1.   */
 793           instrName = "nop";
 794           decodingClass = CLASS_A4_OP3_SUBOPC3F;
 795         }
 796       else
 797         instrName = "xor";
 798       break;
 799
 800     default:
 801       instrName = instruction_name (state,state->_opcode,0,&flags);
 802       /* if (instrName) printf("FLAGS=0x%x\n", flags);  */
 803       if (!instrName)
 804         {
 805           instrName = "???";
 806           state->flow=invalid_instr;
 807         }
 808       if (flags & IGNORE_FIRST_OPD)
 809         ignoreFirstOpd = 1;
 810       break;
 811     }
 812
 813   fieldAisReg = fieldBisReg = fieldCisReg = 1; /* Assume regs for now.  */
 814   flag = cond = is_shimm = is_limm = 0;
 815   state->nullifyMode = BR_exec_when_no_jump;    /* 0  */
 816   signExtend = addrWriteBack = directMem = 0;
 817   usesAuxReg = 0;
 818
 819   switch (decodingClass)
 820     {
 821     case CLASS_A4_ARITH:
 822       CHECK_FIELD_A ();
 823       CHECK_FIELD_B ();
 824       if (!repeatsOp)
 825         CHECK_FIELD_C ();
 826       CHECK_FLAG_COND_NULLIFY ();
 827
 828       write_instr_name ();
 829       if (!ignoreFirstOpd)
 830         {
 831           WRITE_FORMAT_x (A);
 832           WRITE_FORMAT_COMMA_x (B);
 833           if (!repeatsOp)
 834             WRITE_FORMAT_COMMA_x (C);
 835           WRITE_NOP_COMMENT ();
 836           arc_sprintf (state, state->operandBuffer, formatString,
 837                       fieldA, fieldB, fieldC);
 838         }
 839       else
 840         {
 841           WRITE_FORMAT_x (B);
 842           if (!repeatsOp)
 843             WRITE_FORMAT_COMMA_x (C);
 844           arc_sprintf (state, state->operandBuffer, formatString,
 845                       fieldB, fieldC);
 846         }
 847       write_comments ();
 848       break;
 849
 850     case CLASS_A4_OP3_GENERAL:
 851       CHECK_FIELD_A ();
 852       CHECK_FIELD_B ();
 853       CHECK_FLAG_COND_NULLIFY ();
 854
 855       write_instr_name ();
 856       if (!ignoreFirstOpd)
 857         {
 858           WRITE_FORMAT_x (A);
 859           WRITE_FORMAT_COMMA_x (B);
 860           WRITE_NOP_COMMENT ();
 861           arc_sprintf (state, state->operandBuffer, formatString,
 862                       fieldA, fieldB);
 863         }
 864       else
 865         {
 866           WRITE_FORMAT_x (B);
 867           arc_sprintf (state, state->operandBuffer, formatString, fieldB);
 868         }
 869       write_comments ();
 870       break;
 871
 872     case CLASS_A4_FLAG:
 873       CHECK_FIELD_B ();
 874       CHECK_FLAG_COND_NULLIFY ();
 875       flag = 0; /* This is the FLAG instruction -- it's redundant.  */
 876
 877       write_instr_name ();
 878       WRITE_FORMAT_x (B);
 879       arc_sprintf (state, state->operandBuffer, formatString, fieldB);
 880       write_comments ();
 881       break;
 882
 883     case CLASS_A4_BRANCH:
 884       fieldA = BITS (state->words[0],7,26) << 2;
 885       fieldA = (fieldA << 10) >> 10; /* Make it signed.  */
 886       fieldA += addr + 4;
 887       CHECK_FLAG_COND_NULLIFY ();
 888       flag = 0;
 889
 890       write_instr_name ();
 891       /* This address could be a label we know. Convert it.  */
 892       if (state->_opcode != op_LPC /* LP  */)
 893         {
 894           add_target (fieldA); /* For debugger.  */
 895           state->flow = state->_opcode == op_BLC /* BL  */
 896             ? direct_call
 897             : direct_jump;
 898           /* indirect calls are achieved by "lr blink,[status];
 899              lr dest<- func addr; j [dest]"  */
 900         }
 901
 902       strcat (formatString, "%s"); /* Address/label name.  */
 903       arc_sprintf (state, state->operandBuffer, formatString,
 904                   post_address (state, fieldA));
 905       write_comments ();
 906       break;
 907
 908     case CLASS_A4_JC:
 909       /* For op_JC -- jump to address specified.
 910          Also covers jump and link--bit 9 of the instr. word
 911          selects whether linked, thus "is_linked" is set above.  */
 912       fieldA = 0;
 913       CHECK_FIELD_B ();
 914       CHECK_FLAG_COND_NULLIFY ();
 915
 916       if (!fieldBisReg)
 917         {
 918           fieldAisReg = 0;
 919           fieldA = (fieldB >> 25) & 0x7F; /* Flags.  */
 920           fieldB = (fieldB & 0xFFFFFF) << 2;
 921           state->flow = is_linked ? direct_call : direct_jump;
 922           add_target (fieldB);
 923           /* Screwy JLcc requires .jd mode to execute correctly
 924              but we pretend it is .nd (no delay slot).  */
 925           if (is_linked && state->nullifyMode == BR_exec_when_jump)
 926             state->nullifyMode = BR_exec_when_no_jump;
 927         }
 928       else
 929         {
 930           state->flow = is_linked ? indirect_call : indirect_jump;
 931           /* We should also treat this as indirect call if NOT linked
 932              but the preceding instruction was a "lr blink,[status]"
 933              and we have a delay slot with "add blink,blink,2".
 934              For now we can't detect such.  */
 935           state->register_for_indirect_jump = fieldB;
 936         }
 937
 938       write_instr_name ();
 939       strcat (formatString,
 940               IS_REG (B) ? "[%r]" : "%s"); /* Address/label name.  */
 941       if (fieldA != 0)
 942         {
 943           fieldAisReg = 0;
 944           WRITE_FORMAT_COMMA_x (A);
 945         }
 946       if (IS_REG (B))
 947         arc_sprintf (state, state->operandBuffer, formatString, fieldB, fieldA);
 948       else
 949         arc_sprintf (state, state->operandBuffer, formatString,
 950                     post_address (state, fieldB), fieldA);
 951       write_comments ();
 952       break;
 953
 954     case CLASS_A4_LD0:
 955       /* LD instruction.
 956          B and C can be regs, or one (both?) can be limm.  */
 957       CHECK_FIELD_A ();
 958       CHECK_FIELD_B ();
 959       CHECK_FIELD_C ();
 960       if (dbg)
 961         printf ("5:b reg %d %d c reg %d %d  \n",
 962                 fieldBisReg,fieldB,fieldCisReg,fieldC);
 963       state->_offset = 0;
 964       state->_ea_present = 1;
 965       if (fieldBisReg)
 966         state->ea_reg1 = fieldB;
 967       else
 968         state->_offset += fieldB;
 969       if (fieldCisReg)
 970         state->ea_reg2 = fieldC;
 971       else
 972         state->_offset += fieldC;
 973       state->_mem_load = 1;
 974
 975       directMem     = BIT (state->words[0], 5);
 976       addrWriteBack = BIT (state->words[0], 3);
 977       signExtend    = BIT (state->words[0], 0);
 978
 979       write_instr_name ();
 980       WRITE_FORMAT_x_COMMA_LB(A);
 981       if (fieldBisReg || fieldB != 0)
 982         WRITE_FORMAT_x_COMMA (B);
 983       else
 984         fieldB = fieldC;
 985
 986       WRITE_FORMAT_x_RB (C);
 987       arc_sprintf (state, state->operandBuffer, formatString,
 988                   fieldA, fieldB, fieldC);
 989       write_comments ();
 990       break;
 991
 992     case CLASS_A4_LD1:
 993       /* LD instruction.  */
 994       CHECK_FIELD_B ();
 995       CHECK_FIELD_A ();
 996       fieldC = FIELDD (state->words[0]);
 997
 998       if (dbg)
 999         printf ("6:b reg %d %d c 0x%x  \n",
1000                 fieldBisReg, fieldB, fieldC);
1001       state->_ea_present = 1;
1002       state->_offset = fieldC;
1003       state->_mem_load = 1;
1004       if (fieldBisReg)
1005         state->ea_reg1 = fieldB;
1006       /* Field B is either a shimm (same as fieldC) or limm (different!)
1007          Say ea is not present, so only one of us will do the name lookup.  */
1008       else
1009         state->_offset += fieldB, state->_ea_present = 0;
1010
1011       directMem     = BIT (state->words[0],14);
1012       addrWriteBack = BIT (state->words[0],12);
1013       signExtend    = BIT (state->words[0],9);
1014
1015       write_instr_name ();
1016       WRITE_FORMAT_x_COMMA_LB (A);
1017       if (!fieldBisReg)
1018         {
1019           fieldB = state->_offset;
1020           WRITE_FORMAT_x_RB (B);
1021         }
1022       else
1023         {
1024           WRITE_FORMAT_x (B);
1025           if (fieldC != 0 && !BIT (state->words[0],13))
1026             {
1027               fieldCisReg = 0;
1028               WRITE_FORMAT_COMMA_x_RB (C);
1029             }
1030           else
1031             WRITE_FORMAT_RB ();
1032         }
1033       arc_sprintf (state, state->operandBuffer, formatString,
1034                   fieldA, fieldB, fieldC);
1035       write_comments ();
1036       break;
1037
1038     case CLASS_A4_ST:
1039       /* ST instruction.  */
1040       CHECK_FIELD_B();
1041       CHECK_FIELD_C();
1042       fieldA = FIELDD(state->words[0]); /* shimm  */
1043
1044       /* [B,A offset]  */
1045       if (dbg) printf("7:b reg %d %x off %x\n",
1046                       fieldBisReg,fieldB,fieldA);
1047       state->_ea_present = 1;
1048       state->_offset = fieldA;
1049       if (fieldBisReg)
1050         state->ea_reg1 = fieldB;
1051       /* Field B is either a shimm (same as fieldA) or limm (different!)
1052          Say ea is not present, so only one of us will do the name lookup.
1053          (for is_limm we do the name translation here).  */
1054       else
1055         state->_offset += fieldB, state->_ea_present = 0;
1056
1057       directMem     = BIT (state->words[0], 26);
1058       addrWriteBack = BIT (state->words[0], 24);
1059
1060       write_instr_name ();
1061       WRITE_FORMAT_x_COMMA_LB(C);
1062
1063       if (!fieldBisReg)
1064         {
1065           fieldB = state->_offset;
1066           WRITE_FORMAT_x_RB (B);
1067         }
1068       else
1069         {
1070           WRITE_FORMAT_x (B);
1071           if (fieldBisReg && fieldA != 0)
1072             {
1073               fieldAisReg = 0;
1074               WRITE_FORMAT_COMMA_x_RB(A);
1075             }
1076           else
1077             WRITE_FORMAT_RB();
1078         }
1079       arc_sprintf (state, state->operandBuffer, formatString,
1080                   fieldC, fieldB, fieldA);
1081       write_comments2 (fieldA);
1082       break;
1083
1084     case CLASS_A4_SR:
1085       /* SR instruction  */
1086       CHECK_FIELD_B();
1087       CHECK_FIELD_C();
1088
1089       write_instr_name ();
1090       WRITE_FORMAT_x_COMMA_LB(C);
1091       /* Try to print B as an aux reg if it is not a core reg.  */
1092       usesAuxReg = 1;
1093       WRITE_FORMAT_x (B);
1094       WRITE_FORMAT_RB ();
1095       arc_sprintf (state, state->operandBuffer, formatString, fieldC, fieldB);
1096       write_comments ();
1097       break;
1098
1099     case CLASS_A4_OP3_SUBOPC3F:
1100       write_instr_name ();
1101       state->operandBuffer[0] = '\0';
1102       break;
1103
1104     case CLASS_A4_LR:
1105       /* LR instruction */
1106       CHECK_FIELD_A ();
1107       CHECK_FIELD_B ();
1108
1109       write_instr_name ();
1110       WRITE_FORMAT_x_COMMA_LB (A);
1111       /* Try to print B as an aux reg if it is not a core reg. */
1112       usesAuxReg = 1;
1113       WRITE_FORMAT_x (B);
1114       WRITE_FORMAT_RB ();
1115       arc_sprintf (state, state->operandBuffer, formatString, fieldA, fieldB);
1116       write_comments ();
1117       break;
1118
1119     default:
1120       mwerror (state, "Bad decoding class in ARC disassembler");
1121       break;
1122     }
1123
1124   state->_cond = cond;
1125   return state->instructionLen = offset;
1126 }
1127
1128
1129 /* Returns the name the user specified core extension register.  */
1130
1131 static const char *
1132 _coreRegName(void * arg ATTRIBUTE_UNUSED, int regval)
1133 {
1134   return arcExtMap_coreRegName (regval);
1135 }
1136
1137 /* Returns the name the user specified AUX extension register.  */
1138
1139 static const char *
1140 _auxRegName(void *_this ATTRIBUTE_UNUSED, int regval)
1141 {
1142   return arcExtMap_auxRegName(regval);
1143 }
1144
1145 /* Returns the name the user specified condition code name.  */
1146
1147 static const char *
1148 _condCodeName(void *_this ATTRIBUTE_UNUSED, int regval)
1149 {
1150   return arcExtMap_condCodeName(regval);
1151 }
1152
1153 /* Returns the name the user specified extension instruction.  */
1154
1155 static const char *
1156 _instName (void *_this ATTRIBUTE_UNUSED, int majop, int minop, int *flags)
1157 {
1158   return arcExtMap_instName(majop, minop, flags);
1159 }
1160
1161 /* Decode an instruction returning the size of the instruction
1162    in bytes or zero if unrecognized.  */
1163
1164 static int
1165 decodeInstr (bfd_vma            address, /* Address of this instruction.  */
1166              disassemble_info * info)
1167 {
1168   int status;
1169   bfd_byte buffer[4];
1170   struct arcDisState s;         /* ARC Disassembler state.  */
1171   void *stream = info->stream;  /* Output stream.  */
1172   fprintf_ftype func = info->fprintf_func;
1173   int bytes;
1174
1175   memset (&s, 0, sizeof(struct arcDisState));
1176
1177   /* read first instruction  */
1178   status = (*info->read_memory_func) (address, buffer, 4, info);
1179   if (status != 0)
1180     {
1181       (*info->memory_error_func) (status, address, info);
1182       return 0;
1183     }
1184   if (info->endian == BFD_ENDIAN_LITTLE)
1185     s.words[0] = bfd_getl32(buffer);
1186   else
1187     s.words[0] = bfd_getb32(buffer);
1188   /* Always read second word in case of limm.  */
1189
1190   /* We ignore the result since last insn may not have a limm.  */
1191   status = (*info->read_memory_func) (address + 4, buffer, 4, info);
1192   if (info->endian == BFD_ENDIAN_LITTLE)
1193     s.words[1] = bfd_getl32(buffer);
1194   else
1195     s.words[1] = bfd_getb32(buffer);
1196
1197   s._this = &s;
1198   s.coreRegName = _coreRegName;
1199   s.auxRegName = _auxRegName;
1200   s.condCodeName = _condCodeName;
1201   s.instName = _instName;
1202
1203   /* Disassemble.  */
1204   bytes = dsmOneArcInst (address, & s);
1205
1206   /* Display the disassembly instruction.  */
1207   (*func) (stream, "%08lx ", s.words[0]);
1208   (*func) (stream, "    ");
1209   (*func) (stream, "%-10s ", s.instrBuffer);
1210
1211   if (__TRANSLATION_REQUIRED (s))
1212     {
1213       bfd_vma addr = s.addresses[s.operandBuffer[1] - '0'];
1214
1215       (*info->print_address_func) ((bfd_vma) addr, info);
1216       (*func) (stream, "\n");
1217     }
1218   else
1219     (*func) (stream, "%s",s.operandBuffer);
1220
1221   return s.instructionLen;
1222 }
1223
1224 /* Return the print_insn function to use.
1225    Side effect: load (possibly empty) extension section  */
1226
1227 disassembler_ftype
1228 arc_get_disassembler (void *ptr)
1229 {
1230   if (ptr)
1231     build_ARC_extmap ((struct bfd *) ptr);
1232   return decodeInstr;
1233 }