diff options
Diffstat (limited to 'bfd/coff-aux.c')
| -rw-r--r-- | bfd/coff-aux.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/bfd/coff-aux.c b/bfd/coff-aux.c new file mode 100644 index 0000000..c94eb3e --- /dev/null +++ b/bfd/coff-aux.c @@ -0,0 +1,332 @@ +/* BFD back-end for Apple M68K COFF A/UX 3.x files. + Copyright 1996 Free Software Foundation, Inc. + Portions written by Richard Henderson <rth@tamu.edu>, + COMMON symbol munging cribbed from cf-m68klynx.c which was + written by Cygnus Support. + +This file is part of BFD, the Binary File Descriptor library. + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program; if not, write to the Free Software +Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#define TARGET_SYM m68kaux_coff_vec +#define TARGET_NAME "coff-m68k-aux" + +#ifndef TARG_AUX +#define TARG_AUX +#endif + +#define COFF_LONG_FILENAMES + +/* 4k pages */ +#define COFF_PAGE_SIZE 0x1000 + +/* On AUX, a STYP_NOLOAD|STYP_BSS section is part of a shared library. */ +#define BSS_NOLOAD_IS_SHARED_LIBRARY + +#define _bfd_m68kcoff_howto_table _bfd_m68kaux_howto_table +#define _bfd_m68kcoff_rtype2howto _bfd_m68kaux_rtype2howto +#define _bfd_m68kcoff_howto2rtype _bfd_m68kaux_howto2rtype +#define _bfd_m68kcoff_reloc_type_lookup _bfd_m68kaux_reloc_type_lookup + +/* Rather than change names lots of places, reuse the same hack */ +#define LYNX_SPECIAL_FN _bfd_m68kaux_special_fn + +#include "bfd.h" +#include "sysdep.h" + +#ifdef ANSI_PROTOTYPES +struct internal_reloc; +struct coff_link_hash_entry; +struct internal_syment; +#endif + + +static bfd_reloc_status_type _bfd_m68kaux_special_fn + PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **)); +static reloc_howto_type *coff_m68k_aux_rtype_to_howto + PARAMS ((bfd *, asection *, struct internal_reloc *, + struct coff_link_hash_entry *, struct internal_syment *, + bfd_vma *)); +static boolean coff_m68k_aux_link_add_one_symbol + PARAMS ((struct bfd_link_info *, bfd *, const char *, flagword, + asection *, bfd_vma, const char *, boolean, boolean, + struct bfd_link_hash_entry **)); + + +#define coff_rtype_to_howto coff_m68k_aux_rtype_to_howto +#define coff_link_add_one_symbol coff_m68k_aux_link_add_one_symbol + + +/* Compute the addend of a reloc. If the reloc is to a common symbol, + the object file contains the value of the common symbol. By the + time this is called, the linker may be using a different symbol + from a different object file with a different value. Therefore, we + hack wildly to locate the original symbol from this file so that we + can make the correct adjustment. This macro sets coffsym to the + symbol from the original file, and uses it to set the addend value + correctly. If this is not a common symbol, the usual addend + calculation is done, except that an additional tweak is needed for + PC relative relocs. + FIXME: This macro refers to symbols and asect; these are from the + calling function, not the macro arguments. */ + +#define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \ + { \ + coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \ + if (ptr && bfd_asymbol_bfd (ptr) != abfd) \ + coffsym = (obj_symbols (abfd) \ + + (cache_ptr->sym_ptr_ptr - symbols)); \ + else if (ptr) \ + coffsym = coff_symbol_from (abfd, ptr); \ + if (coffsym != (coff_symbol_type *) NULL \ + && coffsym->native->u.syment.n_scnum == 0) \ + cache_ptr->addend = - coffsym->native->u.syment.n_value; \ + else if (ptr && bfd_asymbol_bfd (ptr) == abfd \ + && ptr->section != (asection *) NULL) \ + cache_ptr->addend = - (ptr->section->vma + ptr->value); \ + else \ + cache_ptr->addend = 0; \ + if (ptr && (reloc.r_type == R_PCRBYTE \ + || reloc.r_type == R_PCRWORD \ + || reloc.r_type == R_PCRLONG)) \ + cache_ptr->addend += asect->vma; \ + } + + + +#include "coff/aux.h" /* override coff/internal.h and coff/m68k.h */ +#include "coff-m68k.c" + + + +/* For some reason when using m68k COFF the value stored in the .text + section for a reference to a common symbol is the value itself plus + any desired offset. (taken from work done by Ian Taylor, Cygnus Support, + for I386 COFF). */ + +/* If we are producing relocateable output, we need to do some + adjustments to the object file that are not done by the + bfd_perform_relocation function. This function is called by every + reloc type to make any required adjustments. */ + +static bfd_reloc_status_type +_bfd_m68kaux_special_fn (abfd, reloc_entry, symbol, data, input_section, + output_bfd, error_message) + bfd *abfd; + arelent *reloc_entry; + asymbol *symbol; + PTR data; + asection *input_section; + bfd *output_bfd; + char **error_message; +{ + symvalue diff; + + if (output_bfd == (bfd *) NULL) + return bfd_reloc_continue; + + if (bfd_is_com_section (symbol->section)) + { + /* We are relocating a common symbol. The current value in the + object file is ORIG + OFFSET, where ORIG is the value of the + common symbol as seen by the object file when it was compiled + (this may be zero if the symbol was undefined) and OFFSET is + the offset into the common symbol (normally zero, but may be + non-zero when referring to a field in a common structure). + ORIG is the negative of reloc_entry->addend, which is set by + the CALC_ADDEND macro below. We want to replace the value in + the object file with NEW + OFFSET, where NEW is the value of + the common symbol which we are going to put in the final + object file. NEW is symbol->value. */ + diff = symbol->value + reloc_entry->addend; + } + else + { + /* For some reason bfd_perform_relocation always effectively + ignores the addend for a COFF target when producing + relocateable output. This seems to be always wrong for 386 + COFF, so we handle the addend here instead. */ + diff = reloc_entry->addend; + } + +#define DOIT(x) \ + x = ((x & ~howto->dst_mask) | \ + (((x & howto->src_mask) + diff) & howto->dst_mask)) + + if (diff != 0) + { + reloc_howto_type *howto = reloc_entry->howto; + unsigned char *addr = (unsigned char *) data + reloc_entry->address; + + switch (howto->size) + { + case 0: + { + char x = bfd_get_8 (abfd, addr); + DOIT (x); + bfd_put_8 (abfd, x, addr); + } + break; + + case 1: + { + short x = bfd_get_16 (abfd, addr); + DOIT (x); + bfd_put_16 (abfd, x, addr); + } + break; + + case 2: + { + long x = bfd_get_32 (abfd, addr); + DOIT (x); + bfd_put_32 (abfd, x, addr); + } + break; + + default: + abort (); + } + } + + /* Now let bfd_perform_relocation finish everything up. */ + return bfd_reloc_continue; +} + + +/* coff-m68k.c uses the special COFF backend linker. We need to + adjust common symbols. */ + +/*ARGSUSED*/ +static reloc_howto_type * +coff_m68k_aux_rtype_to_howto (abfd, sec, rel, h, sym, addendp) + bfd *abfd; + asection *sec; + struct internal_reloc *rel; + struct coff_link_hash_entry *h; + struct internal_syment *sym; + bfd_vma *addendp; +{ + arelent relent; + reloc_howto_type *howto; + + RTYPE2HOWTO (&relent, rel); + + howto = relent.howto; + + if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0) + { + /* This is a common symbol. The section contents include the + size (sym->n_value) as an addend. The relocate_section + function will be adding in the final value of the symbol. We + need to subtract out the current size in order to get the + correct result. */ + BFD_ASSERT (h != NULL); + *addendp -= sym->n_value; + } + + /* If the output symbol is common (in which case this must be a + relocateable link), we need to add in the final size of the + common symbol. */ + if (h != NULL && h->root.type == bfd_link_hash_common) + *addendp += h->root.u.c.size; + + return howto; +} + + +/* We need non-absolute symbols to override absolute symbols. This + mirrors Apple's "solution" to let a static library symbol override + a shared library symbol. On the whole not a good thing, given how + shared libraries work here, but can work if you are careful with + what you include in the shared object. */ + +boolean +coff_m68k_aux_link_add_one_symbol (info, abfd, name, flags, section, value, + string, copy, collect, hashp) + struct bfd_link_info *info; + bfd *abfd; + const char *name; + flagword flags; + asection *section; + bfd_vma value; + const char *string; + boolean copy; + boolean collect; + struct bfd_link_hash_entry **hashp; +{ + struct bfd_link_hash_entry *h; + + if ((flags & (BSF_WARNING | BSF_CONSTRUCTOR | BSF_WEAK)) == 0 && + !bfd_is_und_section (section) && + !bfd_is_com_section (section)) + { + /* The new symbol is a definition or an indirect definition */ + + /* This bit copied from linker.c */ + if (hashp != NULL && *hashp != NULL) + { + h = *hashp; + BFD_ASSERT (strcmp (h->root.string, name) == 0); + } + else + { + h = bfd_link_hash_lookup (info->hash, name, true, copy, false); + if (h == NULL) + { + if (hashp != NULL) + *hashp = NULL; + return false; + } + } + + if (info->notice_hash != (struct bfd_hash_table *) NULL + && (bfd_hash_lookup (info->notice_hash, name, false, false) + != (struct bfd_hash_entry *) NULL)) + { + if (! (*info->callbacks->notice) (info, name, abfd, section, value)) + return false; + } + + if (hashp != (struct bfd_link_hash_entry **) NULL) + *hashp = h; + /* end duplication from linker.c */ + + if (h->type == bfd_link_hash_defined + || h->type == bfd_link_hash_indirect) + { + asection *msec; + + if (h->type == bfd_link_hash_defined) + msec = h->u.def.section; + else + msec = bfd_ind_section_ptr; + + if (bfd_is_abs_section (msec) && !bfd_is_abs_section (section)) + { + h->u.def.section = section; + h->u.def.value = value; + return true; + } + else if (bfd_is_abs_section (section) && !bfd_is_abs_section (msec)) + return true; + } + } + + /* If we didn't exit early, finish processing in the generic routine */ + return _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section, + value, string, copy, collect, + hashp); +} |