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author | Richard Henderson <rth@redhat.com> | 1999-05-03 07:29:11 +0000 |
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committer | Richard Henderson <rth@redhat.com> | 1999-05-03 07:29:11 +0000 |
commit | 252b5132c753830d5fd56823373aed85f2a0db63 (patch) | |
tree | 1af963bfd8d3e55167b81def4207f175eaff3a56 /bfd/coff-i386.c | |
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19990502 sourceware importbinu_ss_19990502
Diffstat (limited to 'bfd/coff-i386.c')
-rw-r--r-- | bfd/coff-i386.c | 637 |
1 files changed, 637 insertions, 0 deletions
diff --git a/bfd/coff-i386.c b/bfd/coff-i386.c new file mode 100644 index 0000000..7898cc1 --- /dev/null +++ b/bfd/coff-i386.c @@ -0,0 +1,637 @@ +/* BFD back-end for Intel 386 COFF files. + Copyright 1990, 91, 92, 93, 94, 95, 96, 97, 1998 + 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. */ + +#include "bfd.h" +#include "sysdep.h" +#include "libbfd.h" + +#include "coff/i386.h" + +#include "coff/internal.h" + +#ifdef COFF_WITH_PE +#include "coff/pe.h" +#endif + +#ifdef COFF_GO32_EXE +#include "coff/go32exe.h" +#endif + +#include "libcoff.h" + +static bfd_reloc_status_type coff_i386_reloc + PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **)); +static reloc_howto_type *coff_i386_rtype_to_howto + PARAMS ((bfd *, asection *, struct internal_reloc *, + struct coff_link_hash_entry *, struct internal_syment *, + + bfd_vma *)); + +#define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2) +/* The page size is a guess based on ELF. */ + +#define COFF_PAGE_SIZE 0x1000 + +/* For some reason when using i386 COFF the value stored in the .text + section for a reference to a common symbol is the value itself plus + any desired offset. Ian Taylor, Cygnus Support. */ + +/* 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 +coff_i386_reloc (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)) + { +#ifndef COFF_WITH_PE + /* 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 + /* In PE mode, we do not offset the common symbol. */ + diff = reloc_entry->addend; +#endif + } + 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; + } + +#ifdef COFF_WITH_PE + /* FIXME: How should this case be handled? */ + if (reloc_entry->howto->type == R_IMAGEBASE && diff != 0) + abort (); +#endif + +#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; +} + +#ifdef COFF_WITH_PE +/* Return true if this relocation should + appear in the output .reloc section. */ + +static boolean in_reloc_p(abfd, howto) + bfd * abfd; + reloc_howto_type *howto; +{ + return ! howto->pc_relative && howto->type != R_IMAGEBASE; +} +#endif + +#ifndef PCRELOFFSET +#define PCRELOFFSET false +#endif + +static reloc_howto_type howto_table[] = +{ + {0}, + {1}, + {2}, + {3}, + {4}, + {5}, + HOWTO (R_DIR32, /* type */ + 0, /* rightshift */ + 2, /* size (0 = byte, 1 = short, 2 = long) */ + 32, /* bitsize */ + false, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_bitfield, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "dir32", /* name */ + true, /* partial_inplace */ + 0xffffffff, /* src_mask */ + 0xffffffff, /* dst_mask */ + true), /* pcrel_offset */ + /* {7}, */ + HOWTO (R_IMAGEBASE, /* type */ + 0, /* rightshift */ + 2, /* size (0 = byte, 1 = short, 2 = long) */ + 32, /* bitsize */ + false, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_bitfield, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "rva32", /* name */ + true, /* partial_inplace */ + 0xffffffff, /* src_mask */ + 0xffffffff, /* dst_mask */ + false), /* pcrel_offset */ + {010}, + {011}, + {012}, + {013}, + {014}, + {015}, + {016}, + HOWTO (R_RELBYTE, /* type */ + 0, /* rightshift */ + 0, /* size (0 = byte, 1 = short, 2 = long) */ + 8, /* bitsize */ + false, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_bitfield, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "8", /* name */ + true, /* partial_inplace */ + 0x000000ff, /* src_mask */ + 0x000000ff, /* dst_mask */ + PCRELOFFSET), /* pcrel_offset */ + HOWTO (R_RELWORD, /* type */ + 0, /* rightshift */ + 1, /* size (0 = byte, 1 = short, 2 = long) */ + 16, /* bitsize */ + false, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_bitfield, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "16", /* name */ + true, /* partial_inplace */ + 0x0000ffff, /* src_mask */ + 0x0000ffff, /* dst_mask */ + PCRELOFFSET), /* pcrel_offset */ + HOWTO (R_RELLONG, /* type */ + 0, /* rightshift */ + 2, /* size (0 = byte, 1 = short, 2 = long) */ + 32, /* bitsize */ + false, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_bitfield, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "32", /* name */ + true, /* partial_inplace */ + 0xffffffff, /* src_mask */ + 0xffffffff, /* dst_mask */ + PCRELOFFSET), /* pcrel_offset */ + HOWTO (R_PCRBYTE, /* type */ + 0, /* rightshift */ + 0, /* size (0 = byte, 1 = short, 2 = long) */ + 8, /* bitsize */ + true, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_signed, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "DISP8", /* name */ + true, /* partial_inplace */ + 0x000000ff, /* src_mask */ + 0x000000ff, /* dst_mask */ + PCRELOFFSET), /* pcrel_offset */ + HOWTO (R_PCRWORD, /* type */ + 0, /* rightshift */ + 1, /* size (0 = byte, 1 = short, 2 = long) */ + 16, /* bitsize */ + true, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_signed, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "DISP16", /* name */ + true, /* partial_inplace */ + 0x0000ffff, /* src_mask */ + 0x0000ffff, /* dst_mask */ + PCRELOFFSET), /* pcrel_offset */ + HOWTO (R_PCRLONG, /* type */ + 0, /* rightshift */ + 2, /* size (0 = byte, 1 = short, 2 = long) */ + 32, /* bitsize */ + true, /* pc_relative */ + 0, /* bitpos */ + complain_overflow_signed, /* complain_on_overflow */ + coff_i386_reloc, /* special_function */ + "DISP32", /* name */ + true, /* partial_inplace */ + 0xffffffff, /* src_mask */ + 0xffffffff, /* dst_mask */ + PCRELOFFSET) /* pcrel_offset */ +}; + +/* Turn a howto into a reloc nunmber */ + +#define SELECT_RELOC(x,howto) { x.r_type = howto->type; } +#define BADMAG(x) I386BADMAG(x) +#define I386 1 /* Customize coffcode.h */ + +#define RTYPE2HOWTO(cache_ptr, dst) \ + (cache_ptr)->howto = howto_table + (dst)->r_type; + +/* For 386 COFF a STYP_NOLOAD | STYP_BSS section is part of a shared + library. On some other COFF targets STYP_BSS is normally + STYP_NOLOAD. */ +#define BSS_NOLOAD_IS_SHARED_LIBRARY + +/* 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 && howto_table[reloc.r_type].pc_relative) \ + cache_ptr->addend += asect->vma; \ + } + +/* We use the special COFF backend linker. For normal i386 COFF, we + can use the generic relocate_section routine. For PE, we need our + own routine. */ + +#ifndef COFF_WITH_PE + +#define coff_relocate_section _bfd_coff_generic_relocate_section + +#else /* COFF_WITH_PE */ + +/* The PE relocate section routine. The only difference between this + and the regular routine is that we don't want to do anything for a + relocateable link. */ + +static boolean coff_pe_i386_relocate_section + PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, + struct internal_reloc *, struct internal_syment *, asection **)); + +static boolean +coff_pe_i386_relocate_section (output_bfd, info, input_bfd, + input_section, contents, relocs, syms, + sections) + bfd *output_bfd; + struct bfd_link_info *info; + bfd *input_bfd; + asection *input_section; + bfd_byte *contents; + struct internal_reloc *relocs; + struct internal_syment *syms; + asection **sections; +{ + if (info->relocateable) + return true; + + return _bfd_coff_generic_relocate_section (output_bfd, info, input_bfd, + input_section, contents, + relocs, syms, sections); +} + +#define coff_relocate_section coff_pe_i386_relocate_section + +#endif /* COFF_WITH_PE */ + +/* Convert an rtype to howto for the COFF backend linker. */ + +static reloc_howto_type * +coff_i386_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; +{ + + reloc_howto_type *howto; + + howto = howto_table + rel->r_type; + +#ifdef COFF_WITH_PE + *addendp = 0; +#endif + + if (howto->pc_relative) + *addendp += sec->vma; + + 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); + +#ifndef COFF_WITH_PE + /* I think we *do* want to bypass this. If we don't, I have + seen some data parameters get the wrong relocation address. + If I link two versions with and without this section bypassed + and then do a binary comparison, the addresses which are + different can be looked up in the map. The case in which + this section has been bypassed has addresses which correspond + to values I can find in the map. */ + *addendp -= sym->n_value; +#endif + } + +#ifndef COFF_WITH_PE + /* 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; +#endif + +#ifdef COFF_WITH_PE + if (howto->pc_relative) + { + *addendp -= 4; + + /* If the symbol is defined, then the generic code is going to + add back the symbol value in order to cancel out an + adjustment it made to the addend. However, we set the addend + to 0 at the start of this function. We need to adjust here, + to avoid the adjustment the generic code will make. FIXME: + This is getting a bit hackish. */ + if (sym != NULL && sym->n_scnum != 0) + *addendp -= sym->n_value; + } + + if (rel->r_type == R_IMAGEBASE) + { + *addendp -= pe_data(sec->output_section->owner)->pe_opthdr.ImageBase; + } +#endif + + return howto; +} + + +#define coff_bfd_reloc_type_lookup coff_i386_reloc_type_lookup + + +static reloc_howto_type * +coff_i386_reloc_type_lookup (abfd, code) + bfd *abfd; + bfd_reloc_code_real_type code; +{ + switch (code) + { + case BFD_RELOC_RVA: + return howto_table +R_IMAGEBASE; + case BFD_RELOC_32: + return howto_table + R_DIR32; + case BFD_RELOC_32_PCREL: + return howto_table + R_PCRLONG; + default: + BFD_FAIL (); + return 0; + } +} + +#define coff_rtype_to_howto coff_i386_rtype_to_howto + +#ifdef TARGET_UNDERSCORE + +/* If i386 gcc uses underscores for symbol names, then it does not use + a leading dot for local labels, so if TARGET_UNDERSCORE is defined + we treat all symbols starting with L as local. */ + +static boolean coff_i386_is_local_label_name PARAMS ((bfd *, const char *)); + +static boolean +coff_i386_is_local_label_name (abfd, name) + bfd *abfd; + const char *name; +{ + if (name[0] == 'L') + return true; + + return _bfd_coff_is_local_label_name (abfd, name); +} + +#define coff_bfd_is_local_label_name coff_i386_is_local_label_name + +#endif /* TARGET_UNDERSCORE */ + +#include "coffcode.h" + +static const bfd_target * +i3coff_object_p (abfd) + bfd *abfd; +{ +#ifdef COFF_IMAGE_WITH_PE + /* We need to hack badly to handle a PE image correctly. In PE + images created by the GNU linker, the offset to the COFF header + is always the size. However, this is not the case in images + generated by other PE linkers. The PE format stores a four byte + offset to the PE signature just before the COFF header at + location 0x3c of the file. We pick up that offset, verify that + the PE signature is there, and then set ourselves up to read in + the COFF header. */ + { + bfd_byte ext_offset[4]; + file_ptr offset; + bfd_byte ext_signature[4]; + unsigned long signature; + + if (bfd_seek (abfd, 0x3c, SEEK_SET) != 0 + || bfd_read (ext_offset, 1, 4, abfd) != 4) + { + if (bfd_get_error () != bfd_error_system_call) + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + offset = bfd_h_get_32 (abfd, ext_offset); + if (bfd_seek (abfd, offset, SEEK_SET) != 0 + || bfd_read (ext_signature, 1, 4, abfd) != 4) + { + if (bfd_get_error () != bfd_error_system_call) + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + signature = bfd_h_get_32 (abfd, ext_signature); + + if (signature != 0x4550) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + /* Here is the hack. coff_object_p wants to read filhsz bytes to + pick up the COFF header. We adjust so that that will work. 20 + is the size of the i386 COFF filehdr. */ + + if (bfd_seek (abfd, + (bfd_tell (abfd) + - bfd_coff_filhsz (abfd) + + 20), + SEEK_SET) + != 0) + { + if (bfd_get_error () != bfd_error_system_call) + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + } +#endif + + return coff_object_p (abfd); +} + +const bfd_target +#ifdef TARGET_SYM + TARGET_SYM = +#else + i386coff_vec = +#endif +{ +#ifdef TARGET_NAME + TARGET_NAME, +#else + "coff-i386", /* name */ +#endif + bfd_target_coff_flavour, + BFD_ENDIAN_LITTLE, /* data byte order is little */ + BFD_ENDIAN_LITTLE, /* header byte order is little */ + + (HAS_RELOC | EXEC_P | /* object flags */ + HAS_LINENO | HAS_DEBUG | + HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), + +#ifndef COFF_WITH_PE + (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC /* section flags */ + | SEC_CODE | SEC_DATA), +#else + (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC /* section flags */ + | SEC_CODE | SEC_DATA + | SEC_LINK_ONCE | SEC_LINK_DUPLICATES), +#endif + +#ifdef TARGET_UNDERSCORE + TARGET_UNDERSCORE, /* leading underscore */ +#else + 0, /* leading underscore */ +#endif + '/', /* ar_pad_char */ + 15, /* ar_max_namelen */ + + bfd_getl64, bfd_getl_signed_64, bfd_putl64, + bfd_getl32, bfd_getl_signed_32, bfd_putl32, + bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ + bfd_getl64, bfd_getl_signed_64, bfd_putl64, + bfd_getl32, bfd_getl_signed_32, bfd_putl32, + bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ + +/* Note that we allow an object file to be treated as a core file as well. */ + {_bfd_dummy_target, i3coff_object_p, /* bfd_check_format */ + bfd_generic_archive_p, i3coff_object_p}, + {bfd_false, coff_mkobject, _bfd_generic_mkarchive, /* bfd_set_format */ + bfd_false}, + {bfd_false, coff_write_object_contents, /* bfd_write_contents */ + _bfd_write_archive_contents, bfd_false}, + + BFD_JUMP_TABLE_GENERIC (coff), + BFD_JUMP_TABLE_COPY (coff), + BFD_JUMP_TABLE_CORE (_bfd_nocore), + BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff), + BFD_JUMP_TABLE_SYMBOLS (coff), + BFD_JUMP_TABLE_RELOCS (coff), + BFD_JUMP_TABLE_WRITE (coff), + BFD_JUMP_TABLE_LINK (coff), + BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), + + COFF_SWAP_TABLE, +}; |