1: /* BFD back-end for OpenRISC 1000 COFF binaries.
    2:    Copyright 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
    3:    Contributed by Ivan Guzvinec  <ivang@opencores.org>
    4: 
    5:    This file is part of BFD, the Binary File Descriptor library.
    6: 
    7:    This program 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 of the License, or
   10:    (at your option) any later version.
   11: 
   12:    This program is distributed in the hope that it will be useful,
   13:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   14:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   15:    GNU General Public License for more details.
   16: 
   17:    You should have received a copy of the GNU General Public License
   18:    along with this program; if not, write to the Free Software
   19:    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   20:    MA 02110-1301, USA.  */
   21: 
   22: #define OR32 1
   23: 
   24: #include "sysdep.h"
   25: #include "bfd.h"
   26: #include "libbfd.h"
   27: #include "coff/or32.h"
   28: #include "coff/internal.h"
   29: #include "libcoff.h"
   30: 
   31: static long get_symbol_value
   32:   PARAMS ((asymbol *));
   33: static bfd_reloc_status_type or32_reloc
   34:   PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
   35: static bfd_boolean coff_or32_relocate_section
   36:   PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
   37:            struct internal_reloc *, struct internal_syment *, asection **));
   38: static bfd_boolean coff_or32_adjust_symndx
   39:   PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *,
   40:            struct internal_reloc *, bfd_boolean *));
   41: static void reloc_processing
   42:   PARAMS ((arelent *, struct internal_reloc *, asymbol **, bfd *, asection *));
   43: 
   44: #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
   45: 
   46: #define INSERT_HWORD(WORD,HWORD)              \
   47:     (((WORD) & 0xffff0000) | ((HWORD)& 0x0000ffff))
   48: #define EXTRACT_HWORD(WORD)                   \
   49:     ((WORD) & 0x0000ffff)
   50: #define SIGN_EXTEND_HWORD(HWORD)              \
   51:     ((HWORD) & 0x8000 ? (HWORD)|(~0xffffL) : (HWORD))
   52: 
   53: #define INSERT_JUMPTARG(WORD,JT)              \
   54:     (((WORD) & 0xfc000000) | ((JT)& 0x03ffffff))
   55: #define EXTRACT_JUMPTARG(WORD)                   \
   56:     ((WORD) & 0x03ffffff)
   57: #define SIGN_EXTEND_JUMPTARG(JT)              \
   58:     ((JT) & 0x04000000 ? (JT)|(~0x03ffffffL) : (JT))
   59: 
   60: /* Provided the symbol, returns the value reffed.  */
   61: 
   62: static long
   63: get_symbol_value (symbol)
   64:      asymbol *symbol;
   65: {
   66:   long relocation = 0;
   67: 
   68:   if (bfd_is_com_section (symbol->section))
   69:     relocation = 0;
   70:   else
   71:     relocation = symbol->value +
   72:       symbol->section->output_section->vma +
   73:       symbol->section->output_offset;
   74: 
   75:   return relocation;
   76: }
   77: 
   78: /* This function is in charge of performing all the or32 relocations.  */
   79: 
   80: static bfd_reloc_status_type
   81: or32_reloc (abfd, reloc_entry, symbol_in, data, input_section, output_bfd,
   82:             error_message)
   83:      bfd *abfd;
   84:      arelent *reloc_entry;
   85:      asymbol *symbol_in;
   86:      PTR data;
   87:      asection *input_section;
   88:      bfd *output_bfd;
   89:      char **error_message;
   90: {
   91:   /* The consth relocation comes in two parts, we have to remember
   92:      the state between calls, in these variables.  */
   93:   static bfd_boolean part1_consth_active = FALSE;
   94:   static unsigned long part1_consth_value;
   95: 
   96:   unsigned long insn;
   97:   unsigned long sym_value;
   98:   unsigned long unsigned_value;
   99:   unsigned short r_type;
  100:   long signed_value;
  101: 
  102:   unsigned long addr = reloc_entry->address ;   /*+ input_section->vma*/
  103:   bfd_byte *hit_data =addr + (bfd_byte *)(data);
  104: 
  105:   r_type = reloc_entry->howto->type;
  106: 
  107:   if (output_bfd)
  108:     {
  109:       /* Partial linking - do nothing.  */
  110:       reloc_entry->address += input_section->output_offset;
  111:       return bfd_reloc_ok;
  112:     }
  113: 
  114:   if (symbol_in != NULL
  115:       && bfd_is_und_section (symbol_in->section))
  116:     {
  117:       /* Keep the state machine happy in case we're called again.  */
  118:       if (r_type == R_IHIHALF)
  119:         {
  120:           part1_consth_active = TRUE;
  121:           part1_consth_value  = 0;
  122:         }
  123: 
  124:       return bfd_reloc_undefined;
  125:     }
  126: 
  127:   if ((part1_consth_active) && (r_type != R_IHCONST))
  128:     {
  129:       part1_consth_active = FALSE;
  130:       *error_message = (char *) "Missing IHCONST";
  131: 
  132:       return bfd_reloc_dangerous;
  133:     }
  134: 
  135:   sym_value = get_symbol_value (symbol_in);
  136: 
  137:   switch (r_type)
  138:     {
  139:     case R_IREL:
  140:       insn = bfd_get_32(abfd, hit_data);
  141: 
  142:       /* Take the value in the field and sign extend it.  */
  143:       signed_value = EXTRACT_JUMPTARG (insn);
  144:       signed_value = SIGN_EXTEND_JUMPTARG (signed_value);
  145:       signed_value <<= 2;
  146: 
  147:       /* See the note on the R_IREL reloc in coff_or32_relocate_section.  */
  148:       if (signed_value == - (long) reloc_entry->address)
  149:         signed_value = 0;
  150: 
  151:       signed_value += sym_value + reloc_entry->addend;
  152:       /* Relative jmp/call, so subtract from the value the
  153:          address of the place we're coming from.  */
  154:       signed_value -= (reloc_entry->address
  155:                        + input_section->output_section->vma
  156:                        + input_section->output_offset);
  157:       if (signed_value > 0x7ffffff || signed_value < -0x8000000)
  158:         return bfd_reloc_overflow;
  159: 
  160:       signed_value >>= 2;
  161:       insn = INSERT_JUMPTARG (insn, signed_value);
  162:       bfd_put_32 (abfd, insn, hit_data);
  163:       break;
  164: 
  165:     case R_ILOHALF:
  166:       insn = bfd_get_32 (abfd, hit_data);
  167:       unsigned_value = EXTRACT_HWORD (insn);
  168:       unsigned_value +=  sym_value + reloc_entry->addend;
  169:       insn = INSERT_HWORD (insn, unsigned_value);
  170:       bfd_put_32 (abfd, insn, hit_data);
  171:       break;
  172: 
  173:     case R_IHIHALF:
  174:       insn = bfd_get_32 (abfd, hit_data);
  175: 
  176:       /* consth, part 1
  177:          Just get the symbol value that is referenced.  */
  178:       part1_consth_active = TRUE;
  179:       part1_consth_value = sym_value + reloc_entry->addend;
  180: 
  181:       /* Don't modify insn until R_IHCONST.  */
  182:       break;
  183: 
  184:     case R_IHCONST:
  185:       insn = bfd_get_32 (abfd, hit_data);
  186: 
  187:       /* consth, part 2
  188:          Now relocate the reference.  */
  189:       if (! part1_consth_active)
  190:         {
  191:           *error_message = (char *) "Missing IHIHALF";
  192:           return bfd_reloc_dangerous;
  193:         }
  194: 
  195:       /* sym_ptr_ptr = r_symndx, in coff_slurp_reloc_table() */
  196:       unsigned_value = 0;   /*EXTRACT_HWORD(insn) << 16;*/
  197:       unsigned_value += reloc_entry->addend; /* r_symndx */
  198:       unsigned_value += part1_consth_value;
  199:       unsigned_value = unsigned_value >> 16;
  200:       insn = INSERT_HWORD (insn, unsigned_value);
  201:       part1_consth_active = FALSE;
  202:       bfd_put_32 (abfd, insn, hit_data);
  203:       break;
  204: 
  205:     case R_BYTE:
  206:       insn = bfd_get_8 (abfd, hit_data);
  207:       unsigned_value = insn + sym_value + reloc_entry->addend;
  208:       if (unsigned_value & 0xffffff00)
  209:         return bfd_reloc_overflow;
  210:       bfd_put_8 (abfd, unsigned_value, hit_data);
  211:       break;
  212: 
  213:     case R_HWORD:
  214:       insn = bfd_get_16 (abfd, hit_data);
  215:       unsigned_value = insn + sym_value + reloc_entry->addend;
  216:       if (unsigned_value & 0xffff0000)
  217:         return bfd_reloc_overflow;
  218:       bfd_put_16 (abfd, insn, hit_data);
  219:       break;
  220: 
  221:     case R_WORD:
  222:       insn = bfd_get_32 (abfd, hit_data);
  223:       insn += sym_value + reloc_entry->addend;
  224:       bfd_put_32 (abfd, insn, hit_data);
  225:       break;
  226: 
  227:     default:
  228:       *error_message = _("Unrecognized reloc");
  229:       return bfd_reloc_dangerous;
  230:     }
  231: 
  232:   return bfd_reloc_ok;
  233: }
  234: 
  235: /*      type     rightshift
  236:            size
  237:         bitsize
  238:              pc-relative
  239:              bitpos
  240:            absolute
  241:                complain_on_overflow
  242:               special_function
  243:                 relocation name
  244:                      partial_inplace
  245:                       src_mask
  246: */
  247: 
  248: /* FIXME: I'm not real sure about this table.  */
  249: static reloc_howto_type howto_table[] =
  250: {
  251:   { R_ABS,      0, 3, 32, FALSE,  0, complain_overflow_bitfield,  or32_reloc, "ABS",     TRUE, 0xffffffff,0xffffffff, FALSE },
  252:     EMPTY_HOWTO (1),
  253:     EMPTY_HOWTO (2),
  254:     EMPTY_HOWTO (3),
  255:     EMPTY_HOWTO (4),
  256:     EMPTY_HOWTO (5),
  257:     EMPTY_HOWTO (6),
  258:     EMPTY_HOWTO (7),
  259:     EMPTY_HOWTO (8),
  260:     EMPTY_HOWTO (9),
  261:     EMPTY_HOWTO (10),
  262:     EMPTY_HOWTO (11),
  263:     EMPTY_HOWTO (12),
  264:     EMPTY_HOWTO (13),
  265:     EMPTY_HOWTO (14),
  266:     EMPTY_HOWTO (15),
  267:     EMPTY_HOWTO (16),
  268:     EMPTY_HOWTO (17),
  269:     EMPTY_HOWTO (18),
  270:     EMPTY_HOWTO (19),
  271:     EMPTY_HOWTO (20),
  272:     EMPTY_HOWTO (21),
  273:     EMPTY_HOWTO (22),
  274:     EMPTY_HOWTO (23),
  275:   { R_IREL,     0, 3, 32, TRUE,   0, complain_overflow_signed,    or32_reloc, "IREL",    TRUE, 0xffffffff,0xffffffff, FALSE },
  276:   { R_IABS,     0, 3, 32, FALSE,  0, complain_overflow_bitfield,  or32_reloc, "IABS",    TRUE, 0xffffffff,0xffffffff, FALSE },
  277:   { R_ILOHALF,  0, 3, 16, TRUE,   0, complain_overflow_signed,    or32_reloc, "ILOHALF", TRUE, 0x0000ffff,0x0000ffff, FALSE },
  278:   { R_IHIHALF,  0, 3, 16, TRUE,   16,complain_overflow_signed,    or32_reloc, "IHIHALF", TRUE, 0xffff0000,0xffff0000, FALSE },
  279:   { R_IHCONST,  0, 3, 16, TRUE,   0, complain_overflow_signed,    or32_reloc, "IHCONST", TRUE, 0xffff0000,0xffff0000, FALSE },
  280:   { R_BYTE,     0, 0, 8,  FALSE,  0, complain_overflow_bitfield,  or32_reloc, "BYTE",    TRUE, 0x000000ff,0x000000ff, FALSE },
  281:   { R_HWORD,    0, 1, 16, FALSE,  0, complain_overflow_bitfield,  or32_reloc, "HWORD",   TRUE, 0x0000ffff,0x0000ffff, FALSE },
  282:   { R_WORD,     0, 2, 32, FALSE,  0, complain_overflow_bitfield,  or32_reloc, "WORD",    TRUE, 0xffffffff,0xffffffff, FALSE },
  283: };
  284: 
  285: #define BADMAG(x) OR32BADMAG (x)
  286: 
  287: #define RELOC_PROCESSING(relent, reloc, symbols, abfd, section) \
  288:   reloc_processing (relent, reloc, symbols, abfd, section)
  289: 
  290: static void
  291: reloc_processing (relent,reloc, symbols, abfd, section)
  292:      arelent *relent;
  293:      struct internal_reloc *reloc;
  294:      asymbol **symbols;
  295:      bfd *abfd;
  296:      asection *section;
  297: {
  298:   static bfd_vma ihihalf_vaddr = (bfd_vma) -1;
  299: 
  300:   relent->address = reloc->r_vaddr;
  301:   relent->howto = howto_table + reloc->r_type;
  302: 
  303:   if (reloc->r_type == R_IHCONST)
  304:     {
  305:       /* The address of an R_IHCONST should always be the address of
  306:          the immediately preceding R_IHIHALF.  relocs generated by gas
  307:          are correct, but relocs generated by High C are different (I
  308:          can't figure out what the address means for High C).  We can
  309:          handle both gas and High C by ignoring the address here, and
  310:          simply reusing the address saved for R_IHIHALF.  */
  311:       if (ihihalf_vaddr == (bfd_vma) -1)
  312:         abort ();
  313: 
  314:       relent->address = ihihalf_vaddr;
  315:       ihihalf_vaddr = (bfd_vma) -1;
  316:       relent->addend = reloc->r_symndx;
  317:       relent->sym_ptr_ptr= bfd_abs_section_ptr->symbol_ptr_ptr;
  318:     }
  319:   else
  320:     {
  321:       relent->sym_ptr_ptr = symbols + obj_convert (abfd)[reloc->r_symndx];
  322:       relent->addend = 0;
  323:       relent->address-= section->vma;
  324: 
  325:       if (reloc->r_type == R_IHIHALF)
  326:         ihihalf_vaddr = relent->address;
  327:       else if (ihihalf_vaddr != (bfd_vma) -1)
  328:         abort ();
  329:     }
  330: }
  331: 
  332: /* The reloc processing routine for the optimized COFF linker.  */
  333: 
  334: static bfd_boolean
  335: coff_or32_relocate_section (output_bfd, info, input_bfd, input_section,
  336:                             contents, relocs, syms, sections)
  337:      bfd *output_bfd ATTRIBUTE_UNUSED;
  338:      struct bfd_link_info *info;
  339:      bfd *input_bfd;
  340:      asection *input_section;
  341:      bfd_byte *contents;
  342:      struct internal_reloc *relocs;
  343:      struct internal_syment *syms;
  344:      asection **sections;
  345: {
  346:   struct internal_reloc *rel;
  347:   struct internal_reloc *relend;
  348:   bfd_boolean hihalf;
  349:   bfd_vma hihalf_val;
  350: 
  351:   /* If we are performing a relocatable link, we don't need to do a
  352:      thing.  The caller will take care of adjusting the reloc
  353:      addresses and symbol indices.  */
  354:   if (info->relocatable)
  355:     return TRUE;
  356: 
  357:   hihalf = FALSE;
  358:   hihalf_val = 0;
  359: 
  360:   rel = relocs;
  361:   relend = rel + input_section->reloc_count;
  362: 
  363:   for (; rel < relend; rel++)
  364:     {
  365:       long symndx;
  366:       bfd_byte *loc;
  367:       struct coff_link_hash_entry *h;
  368:       struct internal_syment *sym;
  369:       asection *sec;
  370:       bfd_vma val;
  371:       bfd_boolean overflow;
  372:       unsigned long insn;
  373:       long signed_value;
  374:       unsigned long unsigned_value;
  375:       bfd_reloc_status_type rstat;
  376: 
  377:       symndx = rel->r_symndx;
  378:       loc = contents + rel->r_vaddr - input_section->vma;
  379: 
  380:       if (symndx == -1 || rel->r_type == R_IHCONST)
  381:         h = NULL;
  382:       else
  383:         h = obj_coff_sym_hashes (input_bfd)[symndx];
  384: 
  385:       sym = NULL;
  386:       sec = NULL;
  387:       val = 0;
  388: 
  389:       /* An R_IHCONST reloc does not have a symbol.  Instead, the
  390:          symbol index is an addend.  R_IHCONST is always used in
  391:          conjunction with R_IHHALF.  */
  392:       if (rel->r_type != R_IHCONST)
  393:         {
  394:           if (h == NULL)
  395:             {
  396:               if (symndx == -1)
  397:                 sec = bfd_abs_section_ptr;
  398:               else
  399:                 {
  400:                   sym = syms + symndx;
  401:                   sec = sections[symndx];
  402:                   val = (sec->output_section->vma
  403:                          + sec->output_offset
  404:                          + sym->n_value
  405:                          - sec->vma);
  406:                 }
  407:             }
  408:           else
  409:             {
  410:               if (h->root.type == bfd_link_hash_defined
  411:                   || h->root.type == bfd_link_hash_defweak)
  412:                 {
  413:                   sec = h->root.u.def.section;
  414:                   val = (h->root.u.def.value
  415:                          + sec->output_section->vma
  416:                          + sec->output_offset);
  417:                 }
  418:               else
  419:                 {
  420:                   if (! ((*info->callbacks->undefined_symbol)
  421:                          (info, h->root.root.string, input_bfd, input_section,
  422:                           rel->r_vaddr - input_section->vma, TRUE)))
  423:                     return FALSE;
  424:                 }
  425:             }
  426: 
  427:           if (hihalf)
  428:             {
  429:               if (! ((*info->callbacks->reloc_dangerous)
  430:                      (info, "missing IHCONST reloc", input_bfd,
  431:                       input_section, rel->r_vaddr - input_section->vma)))
  432:                 return FALSE;
  433:               hihalf = FALSE;
  434:             }
  435:         }
  436: 
  437:       overflow = FALSE;
  438: 
  439:       switch (rel->r_type)
  440:         {
  441:         default:
  442:           bfd_set_error (bfd_error_bad_value);
  443:           return FALSE;
  444: 
  445:         case R_IREL:
  446:           insn = bfd_get_32 (input_bfd, loc);
  447: 
  448:           /* Extract the addend.  */
  449:           signed_value = EXTRACT_JUMPTARG (insn);
  450:           signed_value = SIGN_EXTEND_JUMPTARG (signed_value);
  451:           signed_value <<= 2;
  452: 
  453:           /* Determine the destination of the jump.  */
  454:           signed_value += val;
  455: 
  456:           /* Make the destination PC relative.  */
  457:           signed_value -= (input_section->output_section->vma
  458:                            + input_section->output_offset
  459:                            + (rel->r_vaddr - input_section->vma));
  460:           if (signed_value > 0x7ffffff || signed_value < - 0x8000000)
  461:             {
  462:               overflow = TRUE;
  463:               signed_value = 0;
  464:             }
  465: 
  466:           /* Put the adjusted value back into the instruction.  */
  467:           signed_value >>= 2;
  468:           insn = INSERT_JUMPTARG(insn, signed_value);
  469: 
  470:           bfd_put_32 (input_bfd, (bfd_vma) insn, loc);
  471:           break;
  472: 
  473:         case R_ILOHALF:
  474:           insn = bfd_get_32 (input_bfd, loc);
  475:           unsigned_value = EXTRACT_HWORD (insn);
  476:           unsigned_value += val;
  477:           insn = INSERT_HWORD (insn, unsigned_value);
  478:           bfd_put_32 (input_bfd, insn, loc);
  479:           break;
  480: 
  481:         case R_IHIHALF:
  482:           /* Save the value for the R_IHCONST reloc.  */
  483:           hihalf = TRUE;
  484:           hihalf_val = val;
  485:           break;
  486: 
  487:         case R_IHCONST:
  488:           if (! hihalf)
  489:             {
  490:               if (! ((*info->callbacks->reloc_dangerous)
  491:                      (info, "missing IHIHALF reloc", input_bfd,
  492:                       input_section, rel->r_vaddr - input_section->vma)))
  493:                 return FALSE;
  494:               hihalf_val = 0;
  495:             }
  496: 
  497:           insn = bfd_get_32 (input_bfd, loc);
  498:           unsigned_value = rel->r_symndx + hihalf_val;
  499:           unsigned_value >>= 16;
  500:           insn = INSERT_HWORD (insn, unsigned_value);
  501:           bfd_put_32 (input_bfd, (bfd_vma) insn, loc);
  502: 
  503:           hihalf = FALSE;
  504:           break;
  505: 
  506:         case R_BYTE:
  507:         case R_HWORD:
  508:         case R_WORD:
  509:           rstat = _bfd_relocate_contents (howto_table + rel->r_type,
  510:                                           input_bfd, val, loc);
  511:           if (rstat == bfd_reloc_overflow)
  512:             overflow = TRUE;
  513:           else if (rstat != bfd_reloc_ok)
  514:             abort ();
  515:           break;
  516:         }
  517: 
  518:       if (overflow)
  519:         {
  520:           const char *name;
  521:           char buf[SYMNMLEN + 1];
  522: 
  523:           if (symndx == -1)
  524:             name = "*ABS*";
  525:           else if (h != NULL)
  526:             name = NULL;
  527:           else if (sym == NULL)
  528:             name = "*unknown*";
  529:           else if (sym->_n._n_n._n_zeroes == 0
  530:                    && sym->_n._n_n._n_offset != 0)
  531:             name = obj_coff_strings (input_bfd) + sym->_n._n_n._n_offset;
  532:           else
  533:             {
  534:               strncpy (buf, sym->_n._n_name, SYMNMLEN);
  535:               buf[SYMNMLEN] = '\0';
  536:               name = buf;
  537:             }
  538: 
  539:           if (! ((*info->callbacks->reloc_overflow)
  540:                  (info, (h ? &h->root : NULL), name,
  541:                   howto_table[rel->r_type].name, (bfd_vma) 0, input_bfd,
  542:                   input_section, rel->r_vaddr - input_section->vma)))
  543:             return FALSE;
  544:         }
  545:     }
  546: 
  547:   return TRUE;
  548: }
  549: 
  550: #define coff_relocate_section coff_or32_relocate_section
  551: 
  552: /* We don't want to change the symndx of a R_IHCONST reloc, since it
  553:    is actually an addend, not a symbol index at all.  */
  554: 
  555: static bfd_boolean
  556: coff_or32_adjust_symndx (obfd, info, ibfd, sec, irel, adjustedp)
  557:      bfd *obfd ATTRIBUTE_UNUSED;
  558:      struct bfd_link_info *info ATTRIBUTE_UNUSED;
  559:      bfd *ibfd ATTRIBUTE_UNUSED;
  560:      asection *sec ATTRIBUTE_UNUSED;
  561:      struct internal_reloc *irel;
  562:      bfd_boolean *adjustedp;
  563: {