diff options
Diffstat (limited to 'contrib/gdb/bfd/cf-m68klynx.c')
| -rw-r--r-- | contrib/gdb/bfd/cf-m68klynx.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/contrib/gdb/bfd/cf-m68klynx.c b/contrib/gdb/bfd/cf-m68klynx.c new file mode 100644 index 0000000..8149dc6 --- /dev/null +++ b/contrib/gdb/bfd/cf-m68klynx.c @@ -0,0 +1,223 @@ +/* BFD back-end for Motorola M68K COFF LynxOS files. + Copyright 1993, 1994, 1995 Free Software Foundation, Inc. + 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 m68klynx_coff_vec +#define TARGET_NAME "coff-m68k-lynx" + +#define LYNXOS + +#define COFF_LONG_FILENAMES + +#define _bfd_m68kcoff_howto_table _bfd_m68klynx_howto_table +#define _bfd_m68kcoff_rtype2howto _bfd_m68klynx_rtype2howto +#define _bfd_m68kcoff_howto2rtype _bfd_m68klynx_howto2rtype +#define _bfd_m68kcoff_reloc_type_lookup _bfd_m68klynx_reloc_type_lookup + +#define LYNX_SPECIAL_FN _bfd_m68klynx_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_m68klynx_special_fn + PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **)); +static reloc_howto_type *coff_m68k_lynx_rtype_to_howto + PARAMS ((bfd *, asection *, struct internal_reloc *, + struct coff_link_hash_entry *, struct internal_syment *, + bfd_vma *)); + +/* 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_m68klynx_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; +} +/* 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; \ + } + +#define coff_rtype_to_howto coff_m68k_lynx_rtype_to_howto + +#include "coff-m68k.c" + +/* coff-m68k.c uses the special COFF backend linker. We need to + adjust common symbols. + + We can't define this function until after we have included + coff-m68k.c, because it uses RTYPE2HOWTO. */ + +/*ARGSUSED*/ +static reloc_howto_type * +coff_m68k_lynx_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; +} |
