opcodes/ia64-opc.c

   1 /* ia64-opc.c -- Functions to access the compacted opcode table
   2    Copyright (C) 1999-2023 Free Software Foundation, Inc.
   3    Written by Bob Manson of Cygnus Solutions, <manson@cygnus.com>
   4
   5    This file is part of the GNU opcodes library.
   6
   7    This library is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    It is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this file; see the file COPYING.  If not, write to the
  19    Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #include "sysdep.h"
  23 #include "libiberty.h"
  24 #include "ia64-asmtab.h"
  25 #include "ia64-asmtab.c"
  26
  27 static void get_opc_prefix (const char **, char *);
  28 static short int find_string_ent (const char *);
  29 static short int find_main_ent (short int);
  30 static short int find_completer (short int, short int, const char *);
  31 static ia64_insn apply_completer (ia64_insn, int);
  32 static int extract_op_bits (int, int, int);
  33 static int extract_op (int, int *, unsigned int *);
  34 static int opcode_verify (ia64_insn, int, enum ia64_insn_type);
  35 static int locate_opcode_ent (ia64_insn, enum ia64_insn_type);
  36 static struct ia64_opcode *make_ia64_opcode
  37   (ia64_insn, const char *, int, int);
  38 static struct ia64_opcode *ia64_find_matching_opcode
  39   (const char *, short int);
  40
  41 const struct ia64_templ_desc ia64_templ_desc[16] =
  42   {
  43     { 0, { IA64_UNIT_M, IA64_UNIT_I, IA64_UNIT_I }, "MII" },    /* 0 */
  44     { 2, { IA64_UNIT_M, IA64_UNIT_I, IA64_UNIT_I }, "MII" },
  45     { 0, { IA64_UNIT_M, IA64_UNIT_L, IA64_UNIT_X }, "MLX" },
  46     { 0, { 0, },                                    "-3-" },
  47     { 0, { IA64_UNIT_M, IA64_UNIT_M, IA64_UNIT_I }, "MMI" },    /* 4 */
  48     { 1, { IA64_UNIT_M, IA64_UNIT_M, IA64_UNIT_I }, "MMI" },
  49     { 0, { IA64_UNIT_M, IA64_UNIT_F, IA64_UNIT_I }, "MFI" },
  50     { 0, { IA64_UNIT_M, IA64_UNIT_M, IA64_UNIT_F }, "MMF" },
  51     { 0, { IA64_UNIT_M, IA64_UNIT_I, IA64_UNIT_B }, "MIB" },    /* 8 */
  52     { 0, { IA64_UNIT_M, IA64_UNIT_B, IA64_UNIT_B }, "MBB" },
  53     { 0, { 0, },                                    "-a-" },
  54     { 0, { IA64_UNIT_B, IA64_UNIT_B, IA64_UNIT_B }, "BBB" },
  55     { 0, { IA64_UNIT_M, IA64_UNIT_M, IA64_UNIT_B }, "MMB" },    /* c */
  56     { 0, { 0, },                                    "-d-" },
  57     { 0, { IA64_UNIT_M, IA64_UNIT_F, IA64_UNIT_B }, "MFB" },
  58     { 0, { 0, },                                    "-f-" },
  59   };
  60
  61
  62 /* Copy the prefix contained in *PTR (up to a '.' or a NUL) to DEST.
  63    PTR will be adjusted to point to the start of the next portion
  64    of the opcode, or at the NUL character. */
  65
  66 static void
  67 get_opc_prefix (const char **ptr, char *dest)
  68 {
  69   char *c = strchr (*ptr, '.');
  70   if (c != NULL)
  71     {
  72       memcpy (dest, *ptr, c - *ptr);
  73       dest[c - *ptr] = '\0';
  74       *ptr = c + 1;
  75     }
  76   else
  77     {
  78       int l = strlen (*ptr);
  79       memcpy (dest, *ptr, l);
  80       dest[l] = '\0';
  81       *ptr += l;
  82     }
  83 }
  84 \f
  85 /* Find the index of the entry in the string table corresponding to
  86    STR; return -1 if one does not exist. */
  87
  88 static short
  89 find_string_ent (const char *str)
  90 {
  91   short start = 0;
  92   short end = sizeof (ia64_strings) / sizeof (const char *);
  93   short i = (start + end) / 2;
  94
  95   if (strcmp (str, ia64_strings[end - 1]) > 0)
  96     {
  97       return -1;
  98     }
  99   while (start <= end)
 100     {
 101       int c = strcmp (str, ia64_strings[i]);
 102       if (c < 0)
 103         {
 104           end = i - 1;
 105         }
 106       else if (c == 0)
 107         {
 108           return i;
 109         }
 110       else
 111         {
 112           start = i + 1;
 113         }
 114       i = (start + end) / 2;
 115     }
 116   return -1;
 117 }
 118 \f
 119 /* Find the opcode in the main opcode table whose name is STRINGINDEX, or
 120    return -1 if one does not exist. */
 121
 122 static short
 123 find_main_ent (short nameindex)
 124 {
 125   short start = 0;
 126   short end = ARRAY_SIZE (main_table);
 127   short i = (start + end) / 2;
 128
 129   if (nameindex < main_table[0].name_index
 130       || nameindex > main_table[end - 1].name_index)
 131     {
 132       return -1;
 133     }
 134   while (start <= end)
 135     {
 136       if (nameindex < main_table[i].name_index)
 137         {
 138           end = i - 1;
 139         }
 140       else if (nameindex == main_table[i].name_index)
 141         {
 142           while (i > 0 && main_table[i - 1].name_index == nameindex)
 143             {
 144               i--;
 145             }
 146           return i;
 147         }
 148       else
 149         {
 150           start = i + 1;
 151         }
 152       i = (start + end) / 2;
 153     }
 154   return -1;
 155 }
 156 \f
 157 /* Find the index of the entry in the completer table that is part of
 158    MAIN_ENT (starting from PREV_COMPLETER) that matches NAME, or
 159    return -1 if one does not exist. */
 160
 161 static short
 162 find_completer (short main_ent, short prev_completer, const char *name)
 163 {
 164   short name_index = find_string_ent (name);
 165
 166   if (name_index < 0)
 167     {
 168       return -1;
 169     }
 170
 171   if (prev_completer == -1)
 172     {
 173       prev_completer = main_table[main_ent].completers;
 174     }
 175   else
 176     {
 177       prev_completer = completer_table[prev_completer].subentries;
 178     }
 179
 180   while (prev_completer != -1)
 181     {
 182       if (completer_table[prev_completer].name_index == name_index)
 183         {
 184           return prev_completer;
 185         }
 186       prev_completer = completer_table[prev_completer].alternative;
 187     }
 188   return -1;
 189 }
 190 \f
 191 /* Apply the completer referred to by COMPLETER_INDEX to OPCODE, and
 192    return the result. */
 193
 194 static ia64_insn
 195 apply_completer (ia64_insn opcode, int completer_index)
 196 {
 197   ia64_insn mask = completer_table[completer_index].mask;
 198   ia64_insn bits = completer_table[completer_index].bits;
 199   int shiftamt = (completer_table[completer_index].offset & 63);
 200
 201   mask = mask << shiftamt;
 202   bits = bits << shiftamt;
 203   opcode = (opcode & ~mask) | bits;
 204   return opcode;
 205 }
 206 \f
 207 /* Extract BITS number of bits starting from OP_POINTER + BITOFFSET in
 208    the dis_table array, and return its value.  (BITOFFSET is numbered
 209    starting from MSB to LSB, so a BITOFFSET of 0 indicates the MSB of the
 210    first byte in OP_POINTER.) */
 211
 212 static int
 213 extract_op_bits (int op_pointer, int bitoffset, int bits)
 214 {
 215   int res = 0;
 216
 217   op_pointer += (bitoffset / 8);
 218
 219   if (bitoffset % 8)
 220     {
 221       unsigned int op = dis_table[op_pointer++];
 222       int numb = 8 - (bitoffset % 8);
 223       int mask = (1 << numb) - 1;
 224       int bata = (bits < numb) ? bits : numb;
 225       int delta = numb - bata;
 226
 227       res = (res << bata) | ((op & mask) >> delta);
 228       bitoffset += bata;
 229       bits -= bata;
 230     }
 231   while (bits >= 8)
 232     {
 233       res = (res << 8) | (dis_table[op_pointer++] & 255);
 234       bits -= 8;
 235     }
 236   if (bits > 0)
 237     {
 238       unsigned int op = (dis_table[op_pointer++] & 255);
 239       res = (res << bits) | (op >> (8 - bits));
 240     }
 241   return res;
 242 }
 243 \f
 244 /* Examine the state machine entry at OP_POINTER in the dis_table
 245    array, and extract its values into OPVAL and OP.  The length of the
 246    state entry in bits is returned. */
 247
 248 static int
 249 extract_op (int op_pointer, int *opval, unsigned int *op)
 250 {
 251   int oplen = 5;
 252
 253   *op = dis_table[op_pointer];
 254
 255   if ((*op) & 0x40)
 256     {
 257       opval[0] = extract_op_bits (op_pointer, oplen, 5);
 258       oplen += 5;
 259     }
 260   switch ((*op) & 0x30)
 261     {
 262     case 0x10:
 263       {
 264         opval[1] = extract_op_bits (op_pointer, oplen, 8);
 265         oplen += 8;
 266         opval[1] += op_pointer;
 267         break;
 268       }
 269     case 0x20:
 270       {
 271         opval[1] = extract_op_bits (op_pointer, oplen, 16);
 272         if (! (opval[1] & 32768))
 273           {
 274             opval[1] += op_pointer;
 275           }
 276         oplen += 16;
 277         break;
 278       }
 279     case 0x30:
 280       {
 281         oplen--;
 282         opval[2] = extract_op_bits (op_pointer, oplen, 12);
 283         oplen += 12;
 284         opval[2] |= 32768;
 285         break;
 286       }
 287     }
 288   if (((*op) & 0x08) && (((*op) & 0x30) != 0x30))
 289     {
 290       opval[2] = extract_op_bits (op_pointer, oplen, 16);
 291       oplen += 16;
 292       if (! (opval[2] & 32768))
 293         {
 294           opval[2] += op_pointer;
 295         }
 296     }
 297   return oplen;
 298 }
 299 \f
 300 /* Returns a non-zero value if the opcode in the main_table list at
 301    PLACE matches OPCODE and is of type TYPE. */
 302
 303 static int
 304 opcode_verify (ia64_insn opcode, int place, enum ia64_insn_type type)
 305 {
 306   if (main_table[place].opcode_type != type)
 307     {
 308       return 0;
 309     }
 310   if (main_table[place].flags
 311       & (IA64_OPCODE_F2_EQ_F3 | IA64_OPCODE_LEN_EQ_64MCNT))
 312     {
 313       const struct ia64_operand *o1, *o2;
 314       ia64_insn f2, f3;
 315
 316       if (main_table[place].flags & IA64_OPCODE_F2_EQ_F3)
 317         {
 318           o1 = elf64_ia64_operands + IA64_OPND_F2;
 319           o2 = elf64_ia64_operands + IA64_OPND_F3;
 320           (*o1->extract) (o1, opcode, &f2);
 321           (*o2->extract) (o2, opcode, &f3);
 322           if (f2 != f3)
 323             return 0;
 324         }
 325       else
 326         {
 327           ia64_insn len, count;
 328
 329           /* length must equal 64-count: */
 330           o1 = elf64_ia64_operands + IA64_OPND_LEN6;
 331           o2 = elf64_ia64_operands + main_table[place].operands[2];
 332           (*o1->extract) (o1, opcode, &len);
 333           (*o2->extract) (o2, opcode, &count);
 334           if (len != 64 - count)
 335             return 0;
 336         }
 337     }
 338   return 1;
 339 }
 340 \f
 341 /* Find an instruction entry in the ia64_dis_names array that matches
 342    opcode OPCODE and is of type TYPE.  Returns either a positive index
 343    into the array, or a negative value if an entry for OPCODE could
 344    not be found.  Checks all matches and returns the one with the highest
 345    priority. */
 346
 347 static int
 348 locate_opcode_ent (ia64_insn opcode, enum ia64_insn_type type)
 349 {
 350   int currtest[41];
 351   int bitpos[41];
 352   int op_ptr[41];
 353   int currstatenum = 0;
 354   short found_disent = -1;
 355   short found_priority = -1;
 356
 357   currtest[currstatenum] = 0;
 358   op_ptr[currstatenum] = 0;
 359   bitpos[currstatenum] = 40;
 360
 361   while (1)
 362     {
 363       int op_pointer = op_ptr[currstatenum];
 364       unsigned int op;
 365       int currbitnum = bitpos[currstatenum];
 366       int oplen;
 367       int opval[3] = {0};
 368       int next_op;
 369       int currbit;
 370
 371       oplen = extract_op (op_pointer, opval, &op);
 372
 373       bitpos[currstatenum] = currbitnum;
 374
 375       /* Skip opval[0] bits in the instruction.  */
 376       if (op & 0x40)
 377         {
 378           currbitnum -= opval[0];
 379         }
 380
 381       if (currbitnum < 0)
 382         currbitnum = 0;
 383
 384       /* The value of the current bit being tested.  */
 385       currbit = opcode & (((ia64_insn) 1) << currbitnum) ? 1 : 0;
 386       next_op = -1;
 387
 388       /* We always perform the tests specified in the current state in
 389          a particular order, falling through to the next test if the
 390          previous one failed. */
 391       switch (currtest[currstatenum])
 392         {
 393         case 0:
 394           currtest[currstatenum]++;
 395           if (currbit == 0 && (op & 0x80))
 396             {
 397               /* Check for a zero bit.  If this test solely checks for
 398                  a zero bit, we can check for up to 8 consecutive zero
 399                  bits (the number to check is specified by the lower 3
 400                  bits in the state code.)
 401
 402                  If the state instruction matches, we go to the very
 403                  next state instruction; otherwise, try the next test. */
 404
 405               if ((op & 0xf8) == 0x80)
 406                 {
 407                   int count = op & 0x7;
 408                   int x;
 409
 410                   for (x = 0; x <= count; x++)
 411                     {
 412                       int i =
 413                         opcode & (((ia64_insn) 1) << (currbitnum - x)) ? 1 : 0;
 414                       if (i)
 415                         {
 416                           break;
 417                         }
 418                     }
 419                   if (x > count)
 420                     {
 421                       next_op = op_pointer + ((oplen + 7) / 8);
 422                       currbitnum -= count;
 423                       break;
 424                     }
 425                 }
 426               else if (! currbit)
 427                 {
 428                   next_op = op_pointer + ((oplen + 7) / 8);
 429                   break;
 430                 }
 431             }
 432           /* FALLTHROUGH */
 433         case 1:
 434           /* If the bit in the instruction is one, go to the state
 435              instruction specified by opval[1]. */
 436           currtest[currstatenum]++;
 437           if (currbit && (op & 0x30) != 0 && ((op & 0x30) != 0x30))
 438             {
 439               next_op = opval[1];
 440               break;
 441             }
 442           /* FALLTHROUGH */
 443         case 2:
 444           /* Don't care.  Skip the current bit and go to the state
 445              instruction specified by opval[2].
 446
 447              An encoding of 0x30 is special; this means that a 12-bit
 448              offset into the ia64_dis_names[] array is specified.  */
 449           currtest[currstatenum]++;
 450           if ((op & 0x08) || ((op & 0x30) == 0x30))
 451             {
 452               next_op = opval[2];
 453               break;
 454             }
 455         }
 456
 457       /* If bit 15 is set in the address of the next state, an offset
 458          in the ia64_dis_names array was specified instead.  We then
 459          check to see if an entry in the list of opcodes matches the
 460          opcode we were given; if so, we have succeeded.  */
 461
 462       if ((next_op >= 0) && (next_op & 32768))
 463         {
 464           short disent = next_op & 32767;
 465           short priority = -1;
 466
 467           if (next_op > 65535)
 468             {
 469               return -1;
 470             }
 471
 472           /* Run through the list of opcodes to check, trying to find
 473              one that matches.  */
 474           while (disent >= 0)
 475             {
 476               int place = ia64_dis_names[disent].insn_index;
 477
 478               priority = ia64_dis_names[disent].priority;
 479
 480               if (opcode_verify (opcode, place, type)
 481                   && priority > found_priority)
 482                 {
 483                   break;
 484                 }
 485               if (ia64_dis_names[disent].next_flag)
 486                 {
 487                   disent++;
 488                 }
 489               else
 490                 {
 491                   disent = -1;
 492                 }
 493             }
 494
 495           if (disent >= 0)
 496             {
 497               found_disent = disent;
 498               found_priority = priority;
 499             }
 500           /* Try the next test in this state, regardless of whether a match
 501              was found. */
 502           next_op = -2;
 503         }
 504
 505       /* next_op == -1 is "back up to the previous state".
 506          next_op == -2 is "stay in this state and try the next test".
 507          Otherwise, transition to the state indicated by next_op. */
 508
 509       if (next_op == -1)
 510         {
 511           currstatenum--;
 512           if (currstatenum < 0)
 513             {
 514               return found_disent;
 515             }
 516         }
 517       else if (next_op >= 0)
 518         {
 519           currstatenum++;
 520           bitpos[currstatenum] = currbitnum - 1;
 521           op_ptr[currstatenum] = next_op;
 522           currtest[currstatenum] = 0;
 523         }
 524     }
 525 }
 526 \f
 527 /* Construct an ia64_opcode entry based on OPCODE, NAME and PLACE. */
 528
 529 static struct ia64_opcode *
 530 make_ia64_opcode (ia64_insn opcode, const char *name, int place, int depind)
 531 {
 532   struct ia64_opcode *res =
 533     (struct ia64_opcode *) xmalloc (sizeof (struct ia64_opcode));
 534   res->name = xstrdup (name);
 535   res->type = main_table[place].opcode_type;
 536   res->num_outputs = main_table[place].num_outputs;
 537   res->opcode = opcode;
 538   res->mask = main_table[place].mask;
 539   res->operands[0] = main_table[place].operands[0];
 540   res->operands[1] = main_table[place].operands[1];
 541   res->operands[2] = main_table[place].operands[2];
 542   res->operands[3] = main_table[place].operands[3];
 543   res->operands[4] = main_table[place].operands[4];
 544   res->flags = main_table[place].flags;
 545   res->ent_index = place;
 546   res->dependencies = &op_dependencies[depind];
 547   return res;
 548 }
 549 \f
 550 /* Determine the ia64_opcode entry for the opcode specified by INSN
 551    and TYPE.  If a valid entry is not found, return NULL. */
 552 struct ia64_opcode *
 553 ia64_dis_opcode (ia64_insn insn, enum ia64_insn_type type)
 554 {
 555   int disent = locate_opcode_ent (insn, type);
 556
 557   if (disent < 0)
 558     {
 559       return NULL;
 560     }
 561   else
 562     {
 563       unsigned int cb = ia64_dis_names[disent].completer_index;
 564       static char name[128];
 565       int place = ia64_dis_names[disent].insn_index;
 566       int ci = main_table[place].completers;
 567       ia64_insn tinsn = main_table[place].opcode;
 568
 569       strcpy (name, ia64_strings [main_table[place].name_index]);
 570
 571       while (cb)
 572         {
 573           if (cb & 1)
 574             {
 575               int cname = completer_table[ci].name_index;
 576
 577               tinsn = apply_completer (tinsn, ci);
 578
 579               if (ia64_strings[cname][0] != '\0')
 580                 {
 581                   strcat (name, ".");
 582                   strcat (name, ia64_strings[cname]);
 583                 }
 584               if (cb != 1)
 585                 {
 586                   ci = completer_table[ci].subentries;
 587                 }
 588             }
 589           else
 590             {
 591               ci = completer_table[ci].alternative;
 592             }
 593           if (ci < 0)
 594             {
 595               abort ();
 596             }
 597           cb = cb >> 1;
 598         }
 599       if (tinsn != (insn & main_table[place].mask))
 600         {
 601           abort ();
 602         }
 603       return make_ia64_opcode (insn, name, place,
 604                                completer_table[ci].dependencies);
 605     }
 606 }
 607 \f
 608 /* Search the main_opcode table starting from PLACE for an opcode that
 609    matches NAME.  Return NULL if one is not found. */
 610
 611 static struct ia64_opcode *
 612 ia64_find_matching_opcode (const char *name, short place)
 613 {
 614   char op[129];
 615   const char *suffix;
 616   short name_index;
 617
 618   if ((unsigned) place >= ARRAY_SIZE (main_table))
 619     return NULL;
 620
 621   if (strlen (name) > 128)
 622     {
 623       return NULL;
 624     }
 625   suffix = name;
 626   get_opc_prefix (&suffix, op);
 627   name_index = find_string_ent (op);
 628   if (name_index < 0)
 629     {
 630       return NULL;
 631     }
 632
 633   while (main_table[place].name_index == name_index)
 634     {
 635       const char *curr_suffix = suffix;
 636       ia64_insn curr_insn = main_table[place].opcode;
 637       short completer = -1;
 638
 639       do {
 640         if (suffix[0] == '\0')
 641           {
 642             completer = find_completer (place, completer, suffix);
 643           }
 644         else
 645           {
 646             get_opc_prefix (&curr_suffix, op);
 647             completer = find_completer (place, completer, op);
 648           }
 649         if (completer != -1)
 650           {
 651             curr_insn = apply_completer (curr_insn, completer);
 652           }
 653       } while (completer != -1 && curr_suffix[0] != '\0');
 654
 655       if (completer != -1 && curr_suffix[0] == '\0'
 656           && completer_table[completer].terminal_completer)
 657         {
 658           int depind = completer_table[completer].dependencies;
 659           return make_ia64_opcode (curr_insn, name, place, depind);
 660         }
 661       else
 662         {
 663           place++;
 664         }
 665     }
 666   return NULL;
 667 }
 668 \f
 669 /* Find the next opcode after PREV_ENT that matches PREV_ENT, or return NULL
 670    if one does not exist.
 671
 672    It is the caller's responsibility to invoke ia64_free_opcode () to
 673    release any resources used by the returned entry. */
 674
 675 struct ia64_opcode *
 676 ia64_find_next_opcode (struct ia64_opcode *prev_ent)
 677 {
 678   return ia64_find_matching_opcode (prev_ent->name,
 679                                     prev_ent->ent_index + 1);
 680 }
 681
 682 /* Find the first opcode that matches NAME, or return NULL if it does
 683    not exist.
 684
 685    It is the caller's responsibility to invoke ia64_free_opcode () to
 686    release any resources used by the returned entry. */
 687
 688 struct ia64_opcode *
 689 ia64_find_opcode (const char *name)
 690 {
 691   char op[129];
 692   const char *suffix;
 693   short place;
 694   short name_index;
 695
 696   if (strlen (name) > 128)
 697     {
 698       return NULL;
 699     }
 700   suffix = name;
 701   get_opc_prefix (&suffix, op);
 702   name_index = find_string_ent (op);
 703   if (name_index < 0)
 704     {
 705       return NULL;
 706     }
 707
 708   place = find_main_ent (name_index);
 709
 710   if (place < 0)
 711     {
 712       return NULL;
 713     }
 714   return ia64_find_matching_opcode (name, place);
 715 }
 716
 717 /* Free any resources used by ENT. */
 718 void
 719 ia64_free_opcode (struct ia64_opcode *ent)
 720 {
 721   free ((void *)ent->name);
 722   free (ent);
 723 }
 724
 725 const struct ia64_dependency *
 726 ia64_find_dependency (int dep_index)
 727 {
 728   dep_index = DEP(dep_index);
 729
 730   if (dep_index < 0
 731       || dep_index >= (int) ARRAY_SIZE (dependencies))
 732     return NULL;
 733
 734   return &dependencies[dep_index];
 735 }