diff options
Diffstat (limited to 'bfd')
| -rw-r--r-- | bfd/ChangeLog | 10 | ||||
| -rw-r--r-- | bfd/mach-o.c | 146 |
2 files changed, 126 insertions, 30 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 9447c63..6503f5c 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,13 @@ +2012-02-23 Iain Sandoe <idsandoe@googlemail.com> + + * mach-o.c (bfd_mach_o_swap_in_non_scattered_reloc): New. + (bfd_mach_o_canonicalize_one_reloc): Swap non-scattered reloc + bit-fields when target and host differ in endian-ness. When + PAIRs are non-scattered find the 'symbol' from the preceding + reloc. Add FIXME re. reloc symbols on section boundaries. + (bfd_mach_o_swap_out_non_scattered_reloc): New. + (bfd_mach_o_write_relocs): Use bfd_mach_o_encode_non_scattered_reloc. + 2012-02-17 Iain Sandoe <idsandoe@googlemail.com> * mach-o-i386.c (i386_howto_table): Add support for 16 bit diff --git a/bfd/mach-o.c b/bfd/mach-o.c index a7b9f80..1f9fc17 100644 --- a/bfd/mach-o.c +++ b/bfd/mach-o.c @@ -975,6 +975,35 @@ bfd_mach_o_get_reloc_upper_bound (bfd *abfd ATTRIBUTE_UNUSED, return (asect->reloc_count + 1) * sizeof (arelent *); } +/* In addition to the need to byte-swap the symbol number, the bit positions + of the fields in the relocation information vary per target endian-ness. */ + +static void +bfd_mach_o_swap_in_non_scattered_reloc (bfd *abfd, bfd_mach_o_reloc_info *rel, + unsigned char *fields) +{ + unsigned char info = fields[3]; + + if (bfd_big_endian (abfd)) + { + rel->r_value = (fields[0] << 16) | (fields[1] << 8) | fields[2]; + rel->r_type = (info >> BFD_MACH_O_BE_TYPE_SHIFT) & BFD_MACH_O_TYPE_MASK; + rel->r_pcrel = (info & BFD_MACH_O_BE_PCREL) ? 1 : 0; + rel->r_length = (info >> BFD_MACH_O_BE_LENGTH_SHIFT) + & BFD_MACH_O_LENGTH_MASK; + rel->r_extern = (info & BFD_MACH_O_BE_EXTERN) ? 1 : 0; + } + else + { + rel->r_value = (fields[2] << 16) | (fields[1] << 8) | fields[0]; + rel->r_type = (info >> BFD_MACH_O_LE_TYPE_SHIFT) & BFD_MACH_O_TYPE_MASK; + rel->r_pcrel = (info & BFD_MACH_O_LE_PCREL) ? 1 : 0; + rel->r_length = (info >> BFD_MACH_O_LE_LENGTH_SHIFT) + & BFD_MACH_O_LENGTH_MASK; + rel->r_extern = (info & BFD_MACH_O_LE_EXTERN) ? 1 : 0; + } +} + static int bfd_mach_o_canonicalize_one_reloc (bfd *abfd, struct mach_o_reloc_info_external *raw, @@ -984,20 +1013,28 @@ bfd_mach_o_canonicalize_one_reloc (bfd *abfd, bfd_mach_o_backend_data *bed = bfd_mach_o_get_backend_data (abfd); bfd_mach_o_reloc_info reloc; bfd_vma addr; - bfd_vma symnum; asymbol **sym; addr = bfd_get_32 (abfd, raw->r_address); - symnum = bfd_get_32 (abfd, raw->r_symbolnum); + res->sym_ptr_ptr = NULL; + res->addend = 0; if (addr & BFD_MACH_O_SR_SCATTERED) { unsigned int j; + bfd_vma symnum = bfd_get_32 (abfd, raw->r_symbolnum); - /* Scattered relocation. - Extract section and offset from r_value. */ - res->sym_ptr_ptr = NULL; - res->addend = 0; + /* Scattered relocation, can't be extern. */ + reloc.r_scattered = 1; + reloc.r_extern = 0; + + /* Extract section and offset from r_value (symnum). */ + reloc.r_value = symnum; + /* FIXME: This breaks when a symbol in a reloc exactly follows the + end of the data for the section (e.g. in a calculation of section + data length). At present, the symbol will end up associated with + the following section or, if it falls within alignment padding, as + null - which will assert later. */ for (j = 0; j < mdata->nsects; j++) { bfd_mach_o_section *sect = mdata->sections[j]; @@ -1008,42 +1045,62 @@ bfd_mach_o_canonicalize_one_reloc (bfd *abfd, break; } } - res->address = BFD_MACH_O_GET_SR_ADDRESS (addr); + + /* Extract the info and address fields from r_address. */ reloc.r_type = BFD_MACH_O_GET_SR_TYPE (addr); reloc.r_length = BFD_MACH_O_GET_SR_LENGTH (addr); reloc.r_pcrel = addr & BFD_MACH_O_SR_PCREL; - reloc.r_scattered = 1; + reloc.r_address = BFD_MACH_O_GET_SR_TYPE (addr); + res->address = BFD_MACH_O_GET_SR_ADDRESS (addr); } else { - unsigned int num = BFD_MACH_O_GET_R_SYMBOLNUM (symnum); - res->addend = 0; - res->address = addr; - if (symnum & BFD_MACH_O_R_EXTERN) - { + unsigned int num; + + /* Non-scattered relocation. */ + reloc.r_scattered = 0; + + /* The value and info fields have to be extracted dependent on target + endian-ness. */ + bfd_mach_o_swap_in_non_scattered_reloc (abfd, &reloc, raw->r_symbolnum); + num = reloc.r_value; + + if (reloc.r_extern) sym = syms + num; - reloc.r_extern = 1; - } - else + else if (reloc.r_scattered + || (reloc.r_type != BFD_MACH_O_GENERIC_RELOC_PAIR)) { BFD_ASSERT (num != 0); BFD_ASSERT (num <= mdata->nsects); sym = mdata->sections[num - 1]->bfdsection->symbol_ptr_ptr; /* For a symbol defined in section S, the addend (stored in the binary) contains the address of the section. To comply with - bfd conventio, substract the section address. + bfd convention, subtract the section address. Use the address from the header, so that the user can modify the vma of the section. */ res->addend = -mdata->sections[num - 1]->addr; - reloc.r_extern = 0; + } + else /* ... The 'symnum' in a non-scattered PAIR will be 0x00ffffff. */ + { + /* Pairs for PPC LO/HI/HA are not scattered, but contain the offset + in the lower 16bits of the address value. So we have to find the + 'symbol' from the preceding reloc. We do this even thoough the + section symbol is probably not needed here, because NULL symbol + values cause an assert in generic BFD code. */ + sym = (res - 1)->sym_ptr_ptr; } res->sym_ptr_ptr = sym; - reloc.r_type = BFD_MACH_O_GET_R_TYPE (symnum); - reloc.r_length = BFD_MACH_O_GET_R_LENGTH (symnum); - reloc.r_pcrel = (symnum & BFD_MACH_O_R_PCREL) ? 1 : 0; - reloc.r_scattered = 0; + + /* The 'address' is just r_address. + ??? maybe this should be masked with 0xffffff for safety. */ + res->address = addr; + reloc.r_address = addr; } + /* We have set up a reloc with all the information present, so the swapper can + modify address, value and addend fields, if necessary, to convey information + in the generic BFD reloc that is mach-o specific. */ + if (!(*bed->_bfd_mach_o_swap_reloc_in)(res, &reloc)) return -1; return 0; @@ -1182,6 +1239,41 @@ bfd_mach_o_canonicalize_dynamic_reloc (bfd *abfd, arelent **rels, return i; } +/* In addition to the need to byte-swap the symbol number, the bit positions + of the fields in the relocation information vary per target endian-ness. */ + +static void +bfd_mach_o_swap_out_non_scattered_reloc (bfd *abfd, unsigned char *fields, + bfd_mach_o_reloc_info *rel) +{ + unsigned char info = 0; + + BFD_ASSERT (rel->r_type <= 15); + BFD_ASSERT (rel->r_length <= 3); + + if (bfd_big_endian (abfd)) + { + fields[0] = (rel->r_value >> 16) & 0xff; + fields[1] = (rel->r_value >> 8) & 0xff; + fields[2] = rel->r_value & 0xff; + info |= rel->r_type << BFD_MACH_O_BE_TYPE_SHIFT; + info |= rel->r_pcrel ? BFD_MACH_O_BE_PCREL : 0; + info |= rel->r_length << BFD_MACH_O_BE_LENGTH_SHIFT; + info |= rel->r_extern ? BFD_MACH_O_BE_EXTERN : 0; + } + else + { + fields[2] = (rel->r_value >> 16) & 0xff; + fields[1] = (rel->r_value >> 8) & 0xff; + fields[0] = rel->r_value & 0xff; + info |= rel->r_type << BFD_MACH_O_LE_TYPE_SHIFT; + info |= rel->r_pcrel ? BFD_MACH_O_LE_PCREL : 0; + info |= rel->r_length << BFD_MACH_O_LE_LENGTH_SHIFT; + info |= rel->r_extern ? BFD_MACH_O_LE_EXTERN : 0; + } + fields[3] = info; +} + static bfd_boolean bfd_mach_o_write_relocs (bfd *abfd, bfd_mach_o_section *section) { @@ -1228,15 +1320,9 @@ bfd_mach_o_write_relocs (bfd *abfd, bfd_mach_o_section *section) } else { - unsigned long v; - bfd_put_32 (abfd, pinfo->r_address, raw.r_address); - v = BFD_MACH_O_SET_R_SYMBOLNUM (pinfo->r_value) - | (pinfo->r_pcrel ? BFD_MACH_O_R_PCREL : 0) - | BFD_MACH_O_SET_R_LENGTH (pinfo->r_length) - | (pinfo->r_extern ? BFD_MACH_O_R_EXTERN : 0) - | BFD_MACH_O_SET_R_TYPE (pinfo->r_type); - bfd_put_32 (abfd, v, raw.r_symbolnum); + bfd_mach_o_swap_out_non_scattered_reloc (abfd, raw.r_symbolnum, + pinfo); } if (bfd_bwrite (&raw, BFD_MACH_O_RELENT_SIZE, abfd) |