gas/config/tc-wasm32.c

   1 /* tc-wasm32.c -- Assembler code for the wasm32 target.
   2
   3    Copyright (C) 2017-2021 Free Software Foundation, Inc.
   4
   5    This file is part of GAS, the GNU Assembler.
   6
   7    GAS is free software; you can redistribute it and/or modify it
   8    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    GAS 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 GAS; see the file COPYING.  If not, write to the Free
  19    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  20    02110-1301, USA.  */
  21
  22 #include "as.h"
  23 #include "safe-ctype.h"
  24 #include "subsegs.h"
  25 #include "dwarf2dbg.h"
  26 #include "dw2gencfi.h"
  27 #include "elf/wasm32.h"
  28 #include <float.h>
  29
  30 enum wasm_class
  31 {
  32   wasm_typed,                   /* a typed opcode: block, loop, or if */
  33   wasm_special,                 /* a special opcode: unreachable, nop, else,
  34                                    or end */
  35   wasm_break,                   /* "br" */
  36   wasm_break_if,                /* "br_if" opcode */
  37   wasm_break_table,             /* "br_table" opcode */
  38   wasm_return,                  /* "return" opcode */
  39   wasm_call,                    /* "call" opcode */
  40   wasm_call_indirect,           /* "call_indirect" opcode */
  41   wasm_get_local,               /* "get_local" and "get_global" */
  42   wasm_set_local,               /* "set_local" and "set_global" */
  43   wasm_tee_local,               /* "tee_local" */
  44   wasm_drop,                    /* "drop" */
  45   wasm_constant_i32,            /* "i32.const" */
  46   wasm_constant_i64,            /* "i64.const" */
  47   wasm_constant_f32,            /* "f32.const" */
  48   wasm_constant_f64,            /* "f64.const" */
  49   wasm_unary,                   /* unary operators */
  50   wasm_binary,                  /* binary operators */
  51   wasm_conv,                    /* conversion operators */
  52   wasm_load,                    /* load operators */
  53   wasm_store,                   /* store operators */
  54   wasm_select,                  /* "select" */
  55   wasm_relational,              /* comparison operators, except for "eqz" */
  56   wasm_eqz,                     /* "eqz" */
  57   wasm_current_memory,          /* "current_memory" */
  58   wasm_grow_memory,             /* "grow_memory" */
  59   wasm_signature                /* "signature", which isn't an opcode */
  60 };
  61
  62 #define WASM_OPCODE(opcode, name, intype, outtype, class, signedness)   \
  63   { name, wasm_ ## class, opcode },
  64
  65 struct wasm32_opcode_s
  66 {
  67   const char *name;
  68   enum wasm_class clas;
  69   unsigned char opcode;
  70 } wasm32_opcodes[] =
  71 {
  72 #include "opcode/wasm.h"
  73   {
  74   NULL, 0, 0}
  75 };
  76
  77 const char comment_chars[] = ";#";
  78 const char line_comment_chars[] = ";#";
  79 const char line_separator_chars[] = "";
  80
  81 const char *md_shortopts = "m:";
  82
  83 const char EXP_CHARS[] = "eE";
  84 const char FLT_CHARS[] = "dD";
  85
  86 /* The target specific pseudo-ops which we support.  */
  87
  88 const pseudo_typeS md_pseudo_table[] =
  89 {
  90   {NULL, NULL, 0}
  91 };
  92
  93 /* Opcode hash table.  */
  94
  95 static htab_t wasm32_hash;
  96
  97 struct option md_longopts[] =
  98 {
  99   {NULL, no_argument, NULL, 0}
 100 };
 101
 102 size_t md_longopts_size = sizeof (md_longopts);
 103
 104 /* No relaxation/no machine-dependent frags.  */
 105
 106 int
 107 md_estimate_size_before_relax (fragS * fragp ATTRIBUTE_UNUSED,
 108                                asection * seg ATTRIBUTE_UNUSED)
 109 {
 110   abort ();
 111   return 0;
 112 }
 113
 114 void
 115 md_show_usage (FILE * stream)
 116 {
 117   fprintf (stream, _("wasm32 assembler options:\n"));
 118 }
 119
 120 /* No machine-dependent options.  */
 121
 122 int
 123 md_parse_option (int c ATTRIBUTE_UNUSED, const char *arg ATTRIBUTE_UNUSED)
 124 {
 125   return 0;
 126 }
 127
 128 /* No machine-dependent symbols.  */
 129
 130 symbolS *
 131 md_undefined_symbol (char *name ATTRIBUTE_UNUSED)
 132 {
 133   return NULL;
 134 }
 135
 136 /* IEEE little-endian floats.  */
 137
 138 const char *
 139 md_atof (int type, char *litP, int *sizeP)
 140 {
 141   return ieee_md_atof (type, litP, sizeP, FALSE);
 142 }
 143
 144 /* No machine-dependent frags.  */
 145
 146 void
 147 md_convert_frag (bfd * abfd ATTRIBUTE_UNUSED,
 148                  asection * sec ATTRIBUTE_UNUSED,
 149                  fragS * fragP ATTRIBUTE_UNUSED)
 150 {
 151   abort ();
 152 }
 153
 154 /* Build opcode hash table, set some flags.  */
 155
 156 void
 157 md_begin (void)
 158 {
 159   struct wasm32_opcode_s *opcode;
 160
 161   wasm32_hash = str_htab_create ();
 162
 163   /* Insert unique names into hash table.  This hash table then
 164      provides a quick index to the first opcode with a particular name
 165      in the opcode table.  */
 166   for (opcode = wasm32_opcodes; opcode->name; opcode++)
 167     str_hash_insert (wasm32_hash, opcode->name, opcode, 0);
 168
 169   linkrelax = 0;
 170   flag_sectname_subst = 1;
 171   flag_no_comments = 0;
 172   flag_keep_locals = 1;
 173 }
 174
 175 /* Do the normal thing for md_section_align.  */
 176
 177 valueT
 178 md_section_align (asection * seg, valueT addr)
 179 {
 180   int align = bfd_section_alignment (seg);
 181   return ((addr + (1 << align) - 1) & -(1 << align));
 182 }
 183
 184 /* Apply a fixup, return TRUE if done (and no relocation is
 185    needed).  */
 186
 187 static bfd_boolean
 188 apply_full_field_fix (fixS * fixP, char *buf, bfd_vma val, int size)
 189 {
 190   if (fixP->fx_addsy != NULL || fixP->fx_pcrel)
 191     {
 192       fixP->fx_addnumber = val;
 193       return FALSE;
 194     }
 195
 196   number_to_chars_littleendian (buf, val, size);
 197   return TRUE;
 198 }
 199
 200 /* Apply a fixup (potentially PC-relative), set the fx_done flag if
 201    done.  */
 202
 203 void
 204 md_apply_fix (fixS * fixP, valueT * valP, segT seg ATTRIBUTE_UNUSED)
 205 {
 206   char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;
 207   long val = (long) *valP;
 208
 209   if (fixP->fx_pcrel)
 210     {
 211       switch (fixP->fx_r_type)
 212         {
 213         default:
 214           bfd_set_error (bfd_error_bad_value);
 215           return;
 216
 217         case BFD_RELOC_32:
 218           fixP->fx_r_type = BFD_RELOC_32_PCREL;
 219           return;
 220         }
 221     }
 222
 223   if (apply_full_field_fix (fixP, buf, val, fixP->fx_size))
 224     fixP->fx_done = 1;
 225 }
 226
 227 /* Skip whitespace.  */
 228
 229 static inline char *
 230 skip_space (char *s)
 231 {
 232   while (*s == ' ' || *s == '\t')
 233     ++s;
 234   return s;
 235 }
 236
 237 /* Allow '/' in opcodes.  */
 238
 239 static inline bfd_boolean
 240 is_part_of_opcode (char c)
 241 {
 242   return is_part_of_name (c) || (c == '/');
 243 }
 244
 245 /* Extract an opcode.  */
 246
 247 static char *
 248 extract_opcode (char *from, char *to, int limit)
 249 {
 250   char *op_end;
 251   int size = 0;
 252
 253   /* Drop leading whitespace.  */
 254   from = skip_space (from);
 255   *to = 0;
 256
 257   /* Find the op code end.  */
 258   for (op_end = from; *op_end != 0 && is_part_of_opcode (*op_end);)
 259     {
 260       to[size++] = *op_end++;
 261       if (size + 1 >= limit)
 262         break;
 263     }
 264
 265   to[size] = 0;
 266   return op_end;
 267 }
 268
 269 /* Produce an unsigned LEB128 integer padded to the right number of
 270    bytes to store BITS bits, of value VALUE.  Uses FRAG_APPEND_1_CHAR
 271    to write.  */
 272
 273 static void
 274 wasm32_put_long_uleb128 (int bits, unsigned long value)
 275 {
 276   unsigned char c;
 277   int i = 0;
 278
 279   do
 280     {
 281       c = value & 0x7f;
 282       value >>= 7;
 283       if (i < (bits - 1) / 7)
 284         c |= 0x80;
 285       FRAG_APPEND_1_CHAR (c);
 286     }
 287   while (++i < (bits + 6) / 7);
 288 }
 289
 290 /* Produce a signed LEB128 integer, using FRAG_APPEND_1_CHAR to
 291    write.  */
 292
 293 static void
 294 wasm32_put_sleb128 (long value)
 295 {
 296   unsigned char c;
 297   int more;
 298
 299   do
 300     {
 301       c = (value & 0x7f);
 302       value >>= 7;
 303       more = !((((value == 0) && ((c & 0x40) == 0))
 304                 || ((value == -1) && ((c & 0x40) != 0))));
 305       if (more)
 306         c |= 0x80;
 307       FRAG_APPEND_1_CHAR (c);
 308     }
 309   while (more);
 310 }
 311
 312 /* Produce an unsigned LEB128 integer, using FRAG_APPEND_1_CHAR to
 313    write.  */
 314
 315 static void
 316 wasm32_put_uleb128 (unsigned long value)
 317 {
 318   unsigned char c;
 319
 320   do
 321     {
 322       c = value & 0x7f;
 323       value >>= 7;
 324       if (value)
 325         c |= 0x80;
 326       FRAG_APPEND_1_CHAR (c);
 327     }
 328   while (value);
 329 }
 330
 331 /* Read an integer expression.  Produce an LEB128-encoded integer if
 332    it's a constant, a padded LEB128 plus a relocation if it's a
 333    symbol, or a special relocation for <expr>@got, <expr>@gotcode, and
 334    <expr>@plt{__sigchar_<signature>}.  */
 335
 336 static bfd_boolean
 337 wasm32_leb128 (char **line, int bits, int sign)
 338 {
 339   char *t = input_line_pointer;
 340   char *str = *line;
 341   char *str0 = str;
 342   struct reloc_list *reloc;
 343   expressionS ex;
 344   int gotrel = 0;
 345   int pltrel = 0;
 346   int code = 0;
 347   const char *relname;
 348
 349   input_line_pointer = str;
 350   expression (&ex);
 351
 352   if (ex.X_op == O_constant && *input_line_pointer != '@')
 353     {
 354       long value = ex.X_add_number;
 355
 356       str = input_line_pointer;
 357       str = skip_space (str);
 358       *line = str;
 359       if (sign)
 360         wasm32_put_sleb128 (value);
 361       else
 362         {
 363           if (value < 0)
 364             as_bad (_("unexpected negative constant"));
 365           wasm32_put_uleb128 (value);
 366         }
 367       input_line_pointer = t;
 368       return str != str0;
 369     }
 370
 371   reloc = XNEW (struct reloc_list);
 372   reloc->u.a.offset_sym = expr_build_dot ();
 373   if (ex.X_op == O_symbol)
 374     {
 375       reloc->u.a.sym = ex.X_add_symbol;
 376       reloc->u.a.addend = ex.X_add_number;
 377     }
 378   else
 379     {
 380       reloc->u.a.sym = make_expr_symbol (&ex);
 381       reloc->u.a.addend = 0;
 382     }
 383   /* i32.const fpointer@gotcode */
 384   if (strncmp (input_line_pointer, "@gotcode", 8) == 0)
 385     {
 386       gotrel = 1;
 387       code = 1;
 388       input_line_pointer += 8;
 389     }
 390   /* i32.const data@got */
 391   else if (strncmp (input_line_pointer, "@got", 4) == 0)
 392     {
 393       gotrel = 1;
 394       input_line_pointer += 4;
 395     }
 396   /* call f@plt{__sigchar_FiiiiE} */
 397   else if (strncmp (input_line_pointer, "@plt", 4) == 0)
 398     {
 399       char *end_of_sig;
 400
 401       pltrel = 1;
 402       code = 1;
 403       input_line_pointer += 4;
 404
 405       if (strncmp (input_line_pointer, "{", 1) == 0
 406           && (end_of_sig = strchr (input_line_pointer, '}')))
 407         {
 408           char *signature;
 409           struct reloc_list *reloc2;
 410           size_t siglength = end_of_sig - (input_line_pointer + 1);
 411
 412           signature = strndup (input_line_pointer + 1, siglength);
 413
 414           reloc2 = XNEW (struct reloc_list);
 415           reloc2->u.a.offset_sym = expr_build_dot ();
 416           reloc2->u.a.sym = symbol_find_or_make (signature);
 417           reloc2->u.a.addend = 0;
 418           reloc2->u.a.howto = bfd_reloc_name_lookup
 419             (stdoutput, "R_WASM32_PLT_SIG");
 420           reloc2->next = reloc_list;
 421           reloc_list = reloc2;
 422           input_line_pointer = end_of_sig + 1;
 423         }
 424       else
 425         {
 426           as_bad (_("no function type on PLT reloc"));
 427         }
 428     }
 429
 430   if (gotrel && code)
 431     relname = "R_WASM32_LEB128_GOT_CODE";
 432   else if (gotrel)
 433     relname = "R_WASM32_LEB128_GOT";
 434   else if (pltrel)
 435     relname = "R_WASM32_LEB128_PLT";
 436   else
 437     relname = "R_WASM32_LEB128";
 438
 439   reloc->u.a.howto = bfd_reloc_name_lookup (stdoutput, relname);
 440   if (!reloc->u.a.howto)
 441     as_bad (_("couldn't find relocation to use"));
 442   reloc->file = as_where (&reloc->line);
 443   reloc->next = reloc_list;
 444   reloc_list = reloc;
 445
 446   str = input_line_pointer;
 447   str = skip_space (str);
 448   *line = str;
 449   wasm32_put_long_uleb128 (bits, 0);
 450   input_line_pointer = t;
 451
 452   return str != str0;
 453 }
 454
 455 /* Read an integer expression and produce an unsigned LEB128 integer,
 456    or a relocation for it.  */
 457
 458 static bfd_boolean
 459 wasm32_uleb128 (char **line, int bits)
 460 {
 461   return wasm32_leb128 (line, bits, 0);
 462 }
 463
 464 /* Read an integer expression and produce a signed LEB128 integer, or
 465    a relocation for it.  */
 466
 467 static bfd_boolean
 468 wasm32_sleb128 (char **line, int bits)
 469 {
 470   return wasm32_leb128 (line, bits, 1);
 471 }
 472
 473 /* Read an f32.  (Like float_cons ('f')).  */
 474
 475 static void
 476 wasm32_f32 (char **line)
 477 {
 478   char *t = input_line_pointer;
 479
 480   input_line_pointer = *line;
 481   float_cons ('f');
 482   *line = input_line_pointer;
 483   input_line_pointer = t;
 484 }
 485
 486 /* Read an f64.  (Like float_cons ('d')).  */
 487
 488 static void
 489 wasm32_f64 (char **line)
 490 {
 491   char *t = input_line_pointer;
 492
 493   input_line_pointer = *line;
 494   float_cons ('d');
 495   *line = input_line_pointer;
 496   input_line_pointer = t;
 497 }
 498
 499 /* Assemble a signature from LINE, replacing it with the new input
 500    pointer.  Signatures are simple expressions matching the regexp
 501    F[ilfd]*v?E, and interpreted as though they were C++-mangled
 502    function types on a 64-bit machine. */
 503
 504 static void
 505 wasm32_signature (char **line)
 506 {
 507   unsigned long count = 0;
 508   char *str = *line;
 509   char *ostr;
 510   char *result;
 511
 512   if (*str++ != 'F')
 513     as_bad (_("Not a function type"));
 514   result = str;
 515   ostr = str + 1;
 516   str++;
 517
 518   while (*str != 'E')
 519     {
 520       switch (*str++)
 521         {
 522         case 'i':
 523         case 'l':
 524         case 'f':
 525         case 'd':
 526           count++;
 527           break;
 528         default:
 529           as_bad (_("Unknown type %c\n"), str[-1]);
 530         }
 531     }
 532   wasm32_put_uleb128 (count);
 533   str = ostr;
 534   while (*str != 'E')
 535     {
 536       switch (*str++)
 537         {
 538         case 'i':
 539           FRAG_APPEND_1_CHAR (BLOCK_TYPE_I32);
 540           break;
 541         case 'l':
 542           FRAG_APPEND_1_CHAR (BLOCK_TYPE_I64);
 543           break;
 544         case 'f':
 545           FRAG_APPEND_1_CHAR (BLOCK_TYPE_F32);
 546           break;
 547         case 'd':
 548           FRAG_APPEND_1_CHAR (BLOCK_TYPE_F64);
 549           break;
 550         default:
 551           as_bad (_("Unknown type"));
 552         }
 553     }
 554   str++;
 555   switch (*result)
 556     {
 557     case 'v':
 558       FRAG_APPEND_1_CHAR (0x00);        /* no return value */
 559       break;
 560     case 'i':
 561       FRAG_APPEND_1_CHAR (0x01);        /* one return value */
 562       FRAG_APPEND_1_CHAR (BLOCK_TYPE_I32);
 563       break;
 564     case 'l':
 565       FRAG_APPEND_1_CHAR (0x01);        /* one return value */
 566       FRAG_APPEND_1_CHAR (BLOCK_TYPE_I64);
 567       break;
 568     case 'f':
 569       FRAG_APPEND_1_CHAR (0x01);        /* one return value */
 570       FRAG_APPEND_1_CHAR (BLOCK_TYPE_F32);
 571       break;
 572     case 'd':
 573       FRAG_APPEND_1_CHAR (0x01);        /* one return value */
 574       FRAG_APPEND_1_CHAR (BLOCK_TYPE_F64);
 575       break;
 576     default:
 577       as_bad (_("Unknown type"));
 578     }
 579   *line = str;
 580 }
 581
 582 /* Main operands function.  Read the operands for OPCODE from LINE,
 583    replacing it with the new input pointer.  */
 584
 585 static void
 586 wasm32_operands (struct wasm32_opcode_s *opcode, char **line)
 587 {
 588   char *str = *line;
 589   unsigned long block_type = 0;
 590
 591   FRAG_APPEND_1_CHAR (opcode->opcode);
 592   str = skip_space (str);
 593   if (str[0] == '[')
 594     {
 595       if (opcode->clas == wasm_typed)
 596         {
 597           str++;
 598           block_type = BLOCK_TYPE_NONE;
 599           if (str[0] != ']')
 600             {
 601               str = skip_space (str);
 602               switch (str[0])
 603                 {
 604                 case 'i':
 605                   block_type = BLOCK_TYPE_I32;
 606                   str++;
 607                   break;
 608                 case 'l':
 609                   block_type = BLOCK_TYPE_I64;
 610                   str++;
 611                   break;
 612                 case 'f':
 613                   block_type = BLOCK_TYPE_F32;
 614                   str++;
 615                   break;
 616                 case 'd':
 617                   block_type = BLOCK_TYPE_F64;
 618                   str++;
 619                   break;
 620                 }
 621               str = skip_space (str);
 622               if (str[0] == ']')
 623                 str++;
 624               else
 625                 as_bad (_("only single block types allowed"));
 626               str = skip_space (str);
 627             }
 628           else
 629             {
 630               str++;
 631               str = skip_space (str);
 632             }
 633         }
 634       else
 635         as_bad (_("instruction does not take a block type"));
 636     }
 637
 638   switch (opcode->clas)
 639     {
 640     case wasm_drop:
 641     case wasm_special:
 642     case wasm_binary:
 643     case wasm_unary:
 644     case wasm_relational:
 645     case wasm_select:
 646     case wasm_eqz:
 647     case wasm_conv:
 648     case wasm_return:
 649       break;
 650     case wasm_typed:
 651       if (block_type == 0)
 652         as_bad (_("missing block type"));
 653       FRAG_APPEND_1_CHAR (block_type);
 654       break;
 655     case wasm_store:
 656     case wasm_load:
 657       if (str[0] == 'a' && str[1] == '=')
 658         {
 659           str += 2;
 660           if (!wasm32_uleb128 (&str, 32))
 661             as_bad (_("missing alignment hint"));
 662         }
 663       else
 664         {
 665           as_bad (_("missing alignment hint"));
 666         }
 667       str = skip_space (str);
 668       if (!wasm32_uleb128 (&str, 32))
 669         as_bad (_("missing offset"));
 670       break;
 671     case wasm_set_local:
 672     case wasm_get_local:
 673     case wasm_tee_local:
 674       if (!wasm32_uleb128 (&str, 32))
 675         as_bad (_("missing local index"));
 676       break;
 677     case wasm_break:
 678     case wasm_break_if:
 679       if (!wasm32_uleb128 (&str, 32))
 680         as_bad (_("missing break count"));
 681       break;
 682     case wasm_current_memory:
 683     case wasm_grow_memory:
 684       if (!wasm32_uleb128 (&str, 32))
 685         as_bad (_("missing reserved current_memory/grow_memory argument"));
 686       break;
 687     case wasm_call:
 688       if (!wasm32_uleb128 (&str, 32))
 689         as_bad (_("missing call argument"));
 690       break;
 691     case wasm_call_indirect:
 692       if (!wasm32_uleb128 (&str, 32))
 693         as_bad (_("missing call signature"));
 694       if (!wasm32_uleb128 (&str, 32))
 695         as_bad (_("missing table index"));
 696       break;
 697     case wasm_constant_i32:
 698       wasm32_sleb128 (&str, 32);
 699       break;
 700     case wasm_constant_i64:
 701       wasm32_sleb128 (&str, 64);
 702       break;
 703     case wasm_constant_f32:
 704       wasm32_f32 (&str);
 705       return;
 706     case wasm_constant_f64:
 707       wasm32_f64 (&str);
 708       return;
 709     case wasm_break_table:
 710       {
 711         do
 712           {
 713             wasm32_uleb128 (&str, 32);
 714             str = skip_space (str);
 715           }
 716         while (str[0]);
 717
 718         break;
 719       }
 720     case wasm_signature:
 721       wasm32_signature (&str);
 722     }
 723   str = skip_space (str);
 724
 725   if (*str)
 726     as_bad (_("junk at end of line, first unrecognized character is `%c'"),
 727             *str);
 728
 729   *line = str;
 730
 731   return;
 732 }
 733
 734 /* Main assembly function.  Find the opcode and call
 735    wasm32_operands().  */
 736
 737 void
 738 md_assemble (char *str)
 739 {
 740   char op[32];
 741   char *t;
 742   struct wasm32_opcode_s *opcode;
 743
 744   str = skip_space (extract_opcode (str, op, sizeof (op)));
 745
 746   if (!op[0])
 747     as_bad (_("can't find opcode "));
 748
 749   opcode = (struct wasm32_opcode_s *) str_hash_find (wasm32_hash, op);
 750
 751   if (opcode == NULL)
 752     {
 753       as_bad (_("unknown opcode `%s'"), op);
 754       return;
 755     }
 756
 757   dwarf2_emit_insn (0);
 758
 759   t = input_line_pointer;
 760   wasm32_operands (opcode, &str);
 761   input_line_pointer = t;
 762 }
 763
 764 /* Don't replace PLT/GOT relocations with section symbols, so they
 765    don't get an addend.  */
 766
 767 int
 768 wasm32_force_relocation (fixS * f)
 769 {
 770   if (f->fx_r_type == BFD_RELOC_WASM32_LEB128_PLT
 771       || f->fx_r_type == BFD_RELOC_WASM32_LEB128_GOT)
 772     return 1;
 773
 774   return 0;
 775 }
 776
 777 /* Don't replace PLT/GOT relocations with section symbols, so they
 778    don't get an addend.  */
 779
 780 bfd_boolean
 781 wasm32_fix_adjustable (fixS * fixP)
 782 {
 783   if (fixP->fx_addsy == NULL)
 784     return TRUE;
 785
 786   if (fixP->fx_r_type == BFD_RELOC_WASM32_LEB128_PLT
 787       || fixP->fx_r_type == BFD_RELOC_WASM32_LEB128_GOT)
 788     return FALSE;
 789
 790   return TRUE;
 791 }
 792
 793 /* Generate a reloc for FIXP.  */
 794
 795 arelent *
 796 tc_gen_reloc (asection * sec ATTRIBUTE_UNUSED, fixS * fixp)
 797 {
 798   arelent *reloc;
 799
 800   reloc = (arelent *) xmalloc (sizeof (*reloc));
 801   reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
 802   *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
 803   reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
 804
 805   /* Make sure none of our internal relocations make it this far.
 806      They'd better have been fully resolved by this point.  */
 807   gas_assert ((int) fixp->fx_r_type > 0);
 808
 809   reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
 810   if (reloc->howto == NULL)
 811     {
 812       as_bad_where (fixp->fx_file, fixp->fx_line,
 813                     _("cannot represent `%s' relocation in object file"),
 814                     bfd_get_reloc_code_name (fixp->fx_r_type));
 815       return NULL;
 816     }
 817
 818   reloc->addend = fixp->fx_offset;
 819
 820   return reloc;
 821 }