| struct bfd_symbol; /* Forward declaration. */
struct reloc_howto_struct
{
/* The type field has mainly a documentary use - the back end can
do what it wants with it, though normally the back end's
external idea of what a reloc number is stored
in this field. For example, a PC relative word relocation
in a coff environment has the type 023 - because that's
what the outside world calls a R_PCRWORD reloc. */
unsigned int type;
/* The value the final relocation is shifted right by. This drops
unwanted data from the relocation. */
unsigned int rightshift;
/* The size of the item to be relocated. This is *not* a
power-of-two measure. To get the number of bytes operated
on by a type of relocation, use bfd_get_reloc_size. */
int size;
/* The number of bits in the item to be relocated. This is used
when doing overflow checking. */
unsigned int bitsize;
/* Notes that the relocation is relative to the location in the
data section of the addend. The relocation function will
subtract from the relocation value the address of the location
being relocated. */
bfd_boolean pc_relative;
/* The bit position of the reloc value in the destination.
The relocated value is left shifted by this amount. */
unsigned int bitpos;
/* What type of overflow error should be checked for when
relocating. */
enum complain_overflow complain_on_overflow;
/* If this field is non null, then the supplied function is
called rather than the normal function. This allows really
strange relocation methods to be accommodated (e.g., i960 callj
instructions). */
bfd_reloc_status_type (*special_function)
(bfd *, arelent *, struct bfd_symbol *, void *, asection *,
bfd *, char **);
/* The textual name of the relocation type. */
char *name;
/* Some formats record a relocation addend in the section contents
rather than with the relocation. For ELF formats this is the
distinction between USE_REL and USE_RELA (though the code checks
for USE_REL == 1/0). The value of this field is TRUE if the
addend is recorded with the section contents; when performing a
partial link (ld -r) the section contents (the data) will be
modified. The value of this field is FALSE if addends are
recorded with the relocation (in arelent.addend); when performing
a partial link the relocation will be modified.
All relocations for all ELF USE_RELA targets should set this field
to FALSE (values of TRUE should be looked on with suspicion).
However, the converse is not true: not all relocations of all ELF
USE_REL targets set this field to TRUE. Why this is so is peculiar
to each particular target. For relocs that aren't used in partial
links (e.g. GOT stuff) it doesn't matter what this is set to. */
bfd_boolean partial_inplace;
/* src_mask selects the part of the instruction (or data) to be used
in the relocation sum. If the target relocations don't have an
addend in the reloc, eg. ELF USE_REL, src_mask will normally equal
dst_mask to extract the addend from the section contents. If
relocations do have an addend in the reloc, eg. ELF USE_RELA, this
field should be zero. Non-zero values for ELF USE_RELA targets are
bogus as in those cases the value in the dst_mask part of the
section contents should be treated as garbage. */
bfd_vma src_mask;
/* dst_mask selects which parts of the instruction (or data) are
replaced with a relocated value. */
bfd_vma dst_mask;
/* When some formats create PC relative instructions, they leave
the value of the pc of the place being relocated in the offset
slot of the instruction, so that a PC relative relocation can
be made just by adding in an ordinary offset (e.g., sun3 a.out).
Some formats leave the displacement part of an instruction
empty (e.g., m88k bcs); this flag signals the fact. */
bfd_boolean pcrel_offset;
};
|