mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-03 04:12:10 +08:00
fca2b81b88
* bfd-in2.h, libbfd.h: Rebuilt.
2268 lines
65 KiB
C
2268 lines
65 KiB
C
/* BFD support for handling relocation entries.
|
|
Copyright (C) 1990, 1991, 1992, 1993 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
|
|
|
/*
|
|
SECTION
|
|
Relocations
|
|
|
|
BFD maintains relocations in much the same way it maintains
|
|
symbols: they are left alone until required, then read in
|
|
en-mass and translated into an internal form. A common
|
|
routine <<bfd_perform_relocation>> acts upon the
|
|
canonical form to do the fixup.
|
|
|
|
Relocations are maintained on a per section basis,
|
|
while symbols are maintained on a per BFD basis.
|
|
|
|
All that a back end has to do to fit the BFD interface is to create
|
|
a <<struct reloc_cache_entry>> for each relocation
|
|
in a particular section, and fill in the right bits of the structures.
|
|
|
|
@menu
|
|
@* typedef arelent::
|
|
@* howto manager::
|
|
@end menu
|
|
|
|
*/
|
|
|
|
/* DO compile in the reloc_code name table from libbfd.h. */
|
|
#define _BFD_MAKE_TABLE_bfd_reloc_code_real
|
|
|
|
#include "bfd.h"
|
|
#include "sysdep.h"
|
|
#include "bfdlink.h"
|
|
#include "libbfd.h"
|
|
/*
|
|
DOCDD
|
|
INODE
|
|
typedef arelent, howto manager, Relocations, Relocations
|
|
|
|
SUBSECTION
|
|
typedef arelent
|
|
|
|
This is the structure of a relocation entry:
|
|
|
|
CODE_FRAGMENT
|
|
.
|
|
.typedef enum bfd_reloc_status
|
|
.{
|
|
. {* No errors detected *}
|
|
. bfd_reloc_ok,
|
|
.
|
|
. {* The relocation was performed, but there was an overflow. *}
|
|
. bfd_reloc_overflow,
|
|
.
|
|
. {* The address to relocate was not within the section supplied. *}
|
|
. bfd_reloc_outofrange,
|
|
.
|
|
. {* Used by special functions *}
|
|
. bfd_reloc_continue,
|
|
.
|
|
. {* Unsupported relocation size requested. *}
|
|
. bfd_reloc_notsupported,
|
|
.
|
|
. {* Unused *}
|
|
. bfd_reloc_other,
|
|
.
|
|
. {* The symbol to relocate against was undefined. *}
|
|
. bfd_reloc_undefined,
|
|
.
|
|
. {* The relocation was performed, but may not be ok - presently
|
|
. generated only when linking i960 coff files with i960 b.out
|
|
. symbols. If this type is returned, the error_message argument
|
|
. to bfd_perform_relocation will be set. *}
|
|
. bfd_reloc_dangerous
|
|
. }
|
|
. bfd_reloc_status_type;
|
|
.
|
|
.
|
|
.typedef struct reloc_cache_entry
|
|
.{
|
|
. {* A pointer into the canonical table of pointers *}
|
|
. struct symbol_cache_entry **sym_ptr_ptr;
|
|
.
|
|
. {* offset in section *}
|
|
. bfd_size_type address;
|
|
.
|
|
. {* addend for relocation value *}
|
|
. bfd_vma addend;
|
|
.
|
|
. {* Pointer to how to perform the required relocation *}
|
|
. const struct reloc_howto_struct *howto;
|
|
.
|
|
.} arelent;
|
|
|
|
*/
|
|
|
|
/*
|
|
DESCRIPTION
|
|
|
|
Here is a description of each of the fields within an <<arelent>>:
|
|
|
|
o <<sym_ptr_ptr>>
|
|
|
|
The symbol table pointer points to a pointer to the symbol
|
|
associated with the relocation request. It is
|
|
the pointer into the table returned by the back end's
|
|
<<get_symtab>> action. @xref{Symbols}. The symbol is referenced
|
|
through a pointer to a pointer so that tools like the linker
|
|
can fix up all the symbols of the same name by modifying only
|
|
one pointer. The relocation routine looks in the symbol and
|
|
uses the base of the section the symbol is attached to and the
|
|
value of the symbol as the initial relocation offset. If the
|
|
symbol pointer is zero, then the section provided is looked up.
|
|
|
|
o <<address>>
|
|
|
|
The <<address>> field gives the offset in bytes from the base of
|
|
the section data which owns the relocation record to the first
|
|
byte of relocatable information. The actual data relocated
|
|
will be relative to this point; for example, a relocation
|
|
type which modifies the bottom two bytes of a four byte word
|
|
would not touch the first byte pointed to in a big endian
|
|
world.
|
|
|
|
o <<addend>>
|
|
|
|
The <<addend>> is a value provided by the back end to be added (!)
|
|
to the relocation offset. Its interpretation is dependent upon
|
|
the howto. For example, on the 68k the code:
|
|
|
|
|
|
| char foo[];
|
|
| main()
|
|
| {
|
|
| return foo[0x12345678];
|
|
| }
|
|
|
|
Could be compiled into:
|
|
|
|
| linkw fp,#-4
|
|
| moveb @@#12345678,d0
|
|
| extbl d0
|
|
| unlk fp
|
|
| rts
|
|
|
|
|
|
This could create a reloc pointing to <<foo>>, but leave the
|
|
offset in the data, something like:
|
|
|
|
|
|
|RELOCATION RECORDS FOR [.text]:
|
|
|offset type value
|
|
|00000006 32 _foo
|
|
|
|
|
|00000000 4e56 fffc ; linkw fp,#-4
|
|
|00000004 1039 1234 5678 ; moveb @@#12345678,d0
|
|
|0000000a 49c0 ; extbl d0
|
|
|0000000c 4e5e ; unlk fp
|
|
|0000000e 4e75 ; rts
|
|
|
|
|
|
Using coff and an 88k, some instructions don't have enough
|
|
space in them to represent the full address range, and
|
|
pointers have to be loaded in two parts. So you'd get something like:
|
|
|
|
|
|
| or.u r13,r0,hi16(_foo+0x12345678)
|
|
| ld.b r2,r13,lo16(_foo+0x12345678)
|
|
| jmp r1
|
|
|
|
|
|
This should create two relocs, both pointing to <<_foo>>, and with
|
|
0x12340000 in their addend field. The data would consist of:
|
|
|
|
|
|
|RELOCATION RECORDS FOR [.text]:
|
|
|offset type value
|
|
|00000002 HVRT16 _foo+0x12340000
|
|
|00000006 LVRT16 _foo+0x12340000
|
|
|
|
|
|00000000 5da05678 ; or.u r13,r0,0x5678
|
|
|00000004 1c4d5678 ; ld.b r2,r13,0x5678
|
|
|00000008 f400c001 ; jmp r1
|
|
|
|
|
|
The relocation routine digs out the value from the data, adds
|
|
it to the addend to get the original offset, and then adds the
|
|
value of <<_foo>>. Note that all 32 bits have to be kept around
|
|
somewhere, to cope with carry from bit 15 to bit 16.
|
|
|
|
One further example is the sparc and the a.out format. The
|
|
sparc has a similar problem to the 88k, in that some
|
|
instructions don't have room for an entire offset, but on the
|
|
sparc the parts are created in odd sized lumps. The designers of
|
|
the a.out format chose to not use the data within the section
|
|
for storing part of the offset; all the offset is kept within
|
|
the reloc. Anything in the data should be ignored.
|
|
|
|
| save %sp,-112,%sp
|
|
| sethi %hi(_foo+0x12345678),%g2
|
|
| ldsb [%g2+%lo(_foo+0x12345678)],%i0
|
|
| ret
|
|
| restore
|
|
|
|
Both relocs contain a pointer to <<foo>>, and the offsets
|
|
contain junk.
|
|
|
|
|
|
|RELOCATION RECORDS FOR [.text]:
|
|
|offset type value
|
|
|00000004 HI22 _foo+0x12345678
|
|
|00000008 LO10 _foo+0x12345678
|
|
|
|
|
|00000000 9de3bf90 ; save %sp,-112,%sp
|
|
|00000004 05000000 ; sethi %hi(_foo+0),%g2
|
|
|00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0
|
|
|0000000c 81c7e008 ; ret
|
|
|00000010 81e80000 ; restore
|
|
|
|
|
|
o <<howto>>
|
|
|
|
The <<howto>> field can be imagined as a
|
|
relocation instruction. It is a pointer to a structure which
|
|
contains information on what to do with all of the other
|
|
information in the reloc record and data section. A back end
|
|
would normally have a relocation instruction set and turn
|
|
relocations into pointers to the correct structure on input -
|
|
but it would be possible to create each howto field on demand.
|
|
|
|
*/
|
|
|
|
/*
|
|
SUBSUBSECTION
|
|
<<enum complain_overflow>>
|
|
|
|
Indicates what sort of overflow checking should be done when
|
|
performing a relocation.
|
|
|
|
CODE_FRAGMENT
|
|
.
|
|
.enum complain_overflow
|
|
.{
|
|
. {* Do not complain on overflow. *}
|
|
. complain_overflow_dont,
|
|
.
|
|
. {* Complain if the bitfield overflows, whether it is considered
|
|
. as signed or unsigned. *}
|
|
. complain_overflow_bitfield,
|
|
.
|
|
. {* Complain if the value overflows when considered as signed
|
|
. number. *}
|
|
. complain_overflow_signed,
|
|
.
|
|
. {* Complain if the value overflows when considered as an
|
|
. unsigned number. *}
|
|
. complain_overflow_unsigned
|
|
.};
|
|
|
|
*/
|
|
|
|
/*
|
|
SUBSUBSECTION
|
|
<<reloc_howto_type>>
|
|
|
|
The <<reloc_howto_type>> is a structure which contains all the
|
|
information that libbfd needs to know to tie up a back end's data.
|
|
|
|
CODE_FRAGMENT
|
|
.struct symbol_cache_entry; {* Forward declaration *}
|
|
.
|
|
.typedef unsigned char bfd_byte;
|
|
.typedef struct reloc_howto_struct reloc_howto_type;
|
|
.
|
|
.struct reloc_howto_struct
|
|
.{
|
|
. {* The type field has mainly a documetary 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. *}
|
|
. 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 accomodated (e.g., i960 callj
|
|
. instructions). *}
|
|
. bfd_reloc_status_type (*special_function)
|
|
. PARAMS ((bfd *abfd,
|
|
. arelent *reloc_entry,
|
|
. struct symbol_cache_entry *symbol,
|
|
. PTR data,
|
|
. asection *input_section,
|
|
. bfd *output_bfd,
|
|
. char **error_message));
|
|
.
|
|
. {* The textual name of the relocation type. *}
|
|
. char *name;
|
|
.
|
|
. {* When performing a partial link, some formats must modify the
|
|
. relocations rather than the data - this flag signals this.*}
|
|
. boolean partial_inplace;
|
|
.
|
|
. {* The src_mask selects which parts of the read in data
|
|
. are to be used in the relocation sum. E.g., if this was an 8 bit
|
|
. bit of data which we read and relocated, this would be
|
|
. 0x000000ff. When we have relocs which have an addend, such as
|
|
. sun4 extended relocs, the value in the offset part of a
|
|
. relocating field is garbage so we never use it. In this case
|
|
. the mask would be 0x00000000. *}
|
|
. bfd_vma src_mask;
|
|
.
|
|
. {* The dst_mask selects which parts of the instruction are replaced
|
|
. into the instruction. In most cases src_mask == dst_mask,
|
|
. except in the above special case, where dst_mask would be
|
|
. 0x000000ff, and src_mask would be 0x00000000. *}
|
|
. 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.*}
|
|
. boolean pcrel_offset;
|
|
.
|
|
.};
|
|
|
|
*/
|
|
|
|
/*
|
|
FUNCTION
|
|
The HOWTO Macro
|
|
|
|
DESCRIPTION
|
|
The HOWTO define is horrible and will go away.
|
|
|
|
|
|
.#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
|
|
. {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
|
|
|
|
DESCRIPTION
|
|
And will be replaced with the totally magic way. But for the
|
|
moment, we are compatible, so do it this way.
|
|
|
|
|
|
.#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
|
|
.
|
|
DESCRIPTION
|
|
Helper routine to turn a symbol into a relocation value.
|
|
|
|
.#define HOWTO_PREPARE(relocation, symbol) \
|
|
. { \
|
|
. if (symbol != (asymbol *)NULL) { \
|
|
. if (bfd_is_com_section (symbol->section)) { \
|
|
. relocation = 0; \
|
|
. } \
|
|
. else { \
|
|
. relocation = symbol->value; \
|
|
. } \
|
|
. } \
|
|
.}
|
|
|
|
*/
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_get_reloc_size
|
|
|
|
SYNOPSIS
|
|
int bfd_get_reloc_size (const reloc_howto_type *);
|
|
|
|
DESCRIPTION
|
|
For a reloc_howto_type that operates on a fixed number of bytes,
|
|
this returns the number of bytes operated on.
|
|
*/
|
|
|
|
int
|
|
bfd_get_reloc_size (howto)
|
|
const reloc_howto_type *howto;
|
|
{
|
|
switch (howto->size)
|
|
{
|
|
case 0: return 1;
|
|
case 1: return 2;
|
|
case 2: return 4;
|
|
case 3: return 0;
|
|
case 4: return 8;
|
|
case -2: return 4;
|
|
default: abort ();
|
|
}
|
|
}
|
|
|
|
/*
|
|
TYPEDEF
|
|
arelent_chain
|
|
|
|
DESCRIPTION
|
|
|
|
How relocs are tied together in an <<asection>>:
|
|
|
|
.typedef struct relent_chain {
|
|
. arelent relent;
|
|
. struct relent_chain *next;
|
|
.} arelent_chain;
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_perform_relocation
|
|
|
|
SYNOPSIS
|
|
bfd_reloc_status_type
|
|
bfd_perform_relocation
|
|
(bfd *abfd,
|
|
arelent *reloc_entry,
|
|
PTR data,
|
|
asection *input_section,
|
|
bfd *output_bfd,
|
|
char **error_message);
|
|
|
|
DESCRIPTION
|
|
If @var{output_bfd} is supplied to this function, the
|
|
generated image will be relocatable; the relocations are
|
|
copied to the output file after they have been changed to
|
|
reflect the new state of the world. There are two ways of
|
|
reflecting the results of partial linkage in an output file:
|
|
by modifying the output data in place, and by modifying the
|
|
relocation record. Some native formats (e.g., basic a.out and
|
|
basic coff) have no way of specifying an addend in the
|
|
relocation type, so the addend has to go in the output data.
|
|
This is no big deal since in these formats the output data
|
|
slot will always be big enough for the addend. Complex reloc
|
|
types with addends were invented to solve just this problem.
|
|
The @var{error_message} argument is set to an error message if
|
|
this return @code{bfd_reloc_dangerous}.
|
|
|
|
*/
|
|
|
|
|
|
bfd_reloc_status_type
|
|
bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd,
|
|
error_message)
|
|
bfd *abfd;
|
|
arelent *reloc_entry;
|
|
PTR data;
|
|
asection *input_section;
|
|
bfd *output_bfd;
|
|
char **error_message;
|
|
{
|
|
bfd_vma relocation;
|
|
bfd_reloc_status_type flag = bfd_reloc_ok;
|
|
bfd_size_type addr = reloc_entry->address;
|
|
bfd_vma output_base = 0;
|
|
const reloc_howto_type *howto = reloc_entry->howto;
|
|
asection *reloc_target_output_section;
|
|
asymbol *symbol;
|
|
|
|
symbol = *(reloc_entry->sym_ptr_ptr);
|
|
if (bfd_is_abs_section (symbol->section)
|
|
&& output_bfd != (bfd *) NULL)
|
|
{
|
|
reloc_entry->address += input_section->output_offset;
|
|
return bfd_reloc_ok;
|
|
}
|
|
|
|
/* If we are not producing relocateable output, return an error if
|
|
the symbol is not defined. An undefined weak symbol is
|
|
considered to have a value of zero (SVR4 ABI, p. 4-27). */
|
|
if (bfd_is_und_section (symbol->section)
|
|
&& (symbol->flags & BSF_WEAK) == 0
|
|
&& output_bfd == (bfd *) NULL)
|
|
flag = bfd_reloc_undefined;
|
|
|
|
/* If there is a function supplied to handle this relocation type,
|
|
call it. It'll return `bfd_reloc_continue' if further processing
|
|
can be done. */
|
|
if (howto->special_function)
|
|
{
|
|
bfd_reloc_status_type cont;
|
|
cont = howto->special_function (abfd, reloc_entry, symbol, data,
|
|
input_section, output_bfd,
|
|
error_message);
|
|
if (cont != bfd_reloc_continue)
|
|
return cont;
|
|
}
|
|
|
|
/* Is the address of the relocation really within the section? */
|
|
if (reloc_entry->address > input_section->_cooked_size)
|
|
return bfd_reloc_outofrange;
|
|
|
|
/* Work out which section the relocation is targetted at and the
|
|
initial relocation command value. */
|
|
|
|
/* Get symbol value. (Common symbols are special.) */
|
|
if (bfd_is_com_section (symbol->section))
|
|
relocation = 0;
|
|
else
|
|
relocation = symbol->value;
|
|
|
|
|
|
reloc_target_output_section = symbol->section->output_section;
|
|
|
|
/* Convert input-section-relative symbol value to absolute. */
|
|
if (output_bfd && howto->partial_inplace == false)
|
|
output_base = 0;
|
|
else
|
|
output_base = reloc_target_output_section->vma;
|
|
|
|
relocation += output_base + symbol->section->output_offset;
|
|
|
|
/* Add in supplied addend. */
|
|
relocation += reloc_entry->addend;
|
|
|
|
/* Here the variable relocation holds the final address of the
|
|
symbol we are relocating against, plus any addend. */
|
|
|
|
if (howto->pc_relative == true)
|
|
{
|
|
/* This is a PC relative relocation. We want to set RELOCATION
|
|
to the distance between the address of the symbol and the
|
|
location. RELOCATION is already the address of the symbol.
|
|
|
|
We start by subtracting the address of the section containing
|
|
the location.
|
|
|
|
If pcrel_offset is set, we must further subtract the position
|
|
of the location within the section. Some targets arrange for
|
|
the addend to be the negative of the position of the location
|
|
within the section; for example, i386-aout does this. For
|
|
i386-aout, pcrel_offset is false. Some other targets do not
|
|
include the position of the location; for example, m88kbcs,
|
|
or ELF. For those targets, pcrel_offset is true.
|
|
|
|
If we are producing relocateable output, then we must ensure
|
|
that this reloc will be correctly computed when the final
|
|
relocation is done. If pcrel_offset is false we want to wind
|
|
up with the negative of the location within the section,
|
|
which means we must adjust the existing addend by the change
|
|
in the location within the section. If pcrel_offset is true
|
|
we do not want to adjust the existing addend at all.
|
|
|
|
FIXME: This seems logical to me, but for the case of
|
|
producing relocateable output it is not what the code
|
|
actually does. I don't want to change it, because it seems
|
|
far too likely that something will break. */
|
|
|
|
relocation -=
|
|
input_section->output_section->vma + input_section->output_offset;
|
|
|
|
if (howto->pcrel_offset == true)
|
|
relocation -= reloc_entry->address;
|
|
}
|
|
|
|
if (output_bfd != (bfd *) NULL)
|
|
{
|
|
if (howto->partial_inplace == false)
|
|
{
|
|
/* This is a partial relocation, and we want to apply the relocation
|
|
to the reloc entry rather than the raw data. Modify the reloc
|
|
inplace to reflect what we now know. */
|
|
reloc_entry->addend = relocation;
|
|
reloc_entry->address += input_section->output_offset;
|
|
return flag;
|
|
}
|
|
else
|
|
{
|
|
/* This is a partial relocation, but inplace, so modify the
|
|
reloc record a bit.
|
|
|
|
If we've relocated with a symbol with a section, change
|
|
into a ref to the section belonging to the symbol. */
|
|
|
|
reloc_entry->address += input_section->output_offset;
|
|
|
|
/* WTF?? */
|
|
if (abfd->xvec->flavour == bfd_target_coff_flavour
|
|
&& strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
|
|
&& strcmp (abfd->xvec->name, "coff-Intel-little") != 0
|
|
&& strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
|
|
{
|
|
#if 1
|
|
/* For m68k-coff, the addend was being subtracted twice during
|
|
relocation with -r. Removing the line below this comment
|
|
fixes that problem; see PR 2953.
|
|
|
|
However, Ian wrote the following, regarding removing the line below,
|
|
which explains why it is still enabled: --djm
|
|
|
|
If you put a patch like that into BFD you need to check all the COFF
|
|
linkers. I am fairly certain that patch will break coff-i386 (e.g.,
|
|
SCO); see coff_i386_reloc in coff-i386.c where I worked around the
|
|
problem in a different way. There may very well be a reason that the
|
|
code works as it does.
|
|
|
|
Hmmm. The first obvious point is that bfd_perform_relocation should
|
|
not have any tests that depend upon the flavour. It's seem like
|
|
entirely the wrong place for such a thing. The second obvious point
|
|
is that the current code ignores the reloc addend when producing
|
|
relocateable output for COFF. That's peculiar. In fact, I really
|
|
have no idea what the point of the line you want to remove is.
|
|
|
|
A typical COFF reloc subtracts the old value of the symbol and adds in
|
|
the new value to the location in the object file (if it's a pc
|
|
relative reloc it adds the difference between the symbol value and the
|
|
location). When relocating we need to preserve that property.
|
|
|
|
BFD handles this by setting the addend to the negative of the old
|
|
value of the symbol. Unfortunately it handles common symbols in a
|
|
non-standard way (it doesn't subtract the old value) but that's a
|
|
different story (we can't change it without losing backward
|
|
compatibility with old object files) (coff-i386 does subtract the old
|
|
value, to be compatible with existing coff-i386 targets, like SCO).
|
|
|
|
So everything works fine when not producing relocateable output. When
|
|
we are producing relocateable output, logically we should do exactly
|
|
what we do when not producing relocateable output. Therefore, your
|
|
patch is correct. In fact, it should probably always just set
|
|
reloc_entry->addend to 0 for all cases, since it is, in fact, going to
|
|
add the value into the object file. This won't hurt the COFF code,
|
|
which doesn't use the addend; I'm not sure what it will do to other
|
|
formats (the thing to check for would be whether any formats both use
|
|
the addend and set partial_inplace).
|
|
|
|
When I wanted to make coff-i386 produce relocateable output, I ran
|
|
into the problem that you are running into: I wanted to remove that
|
|
line. Rather than risk it, I made the coff-i386 relocs use a special
|
|
function; it's coff_i386_reloc in coff-i386.c. The function
|
|
specifically adds the addend field into the object file, knowing that
|
|
bfd_perform_relocation is not going to. If you remove that line, then
|
|
coff-i386.c will wind up adding the addend field in twice. It's
|
|
trivial to fix; it just needs to be done.
|
|
|
|
The problem with removing the line is just that it may break some
|
|
working code. With BFD it's hard to be sure of anything. The right
|
|
way to deal with this is simply to build and test at least all the
|
|
supported COFF targets. It should be straightforward if time and disk
|
|
space consuming. For each target:
|
|
1) build the linker
|
|
2) generate some executable, and link it using -r (I would
|
|
probably use paranoia.o and link against newlib/libc.a, which
|
|
for all the supported targets would be available in
|
|
/usr/cygnus/progressive/H-host/target/lib/libc.a).
|
|
3) make the change to reloc.c
|
|
4) rebuild the linker
|
|
5) repeat step 2
|
|
6) if the resulting object files are the same, you have at least
|
|
made it no worse
|
|
7) if they are different you have to figure out which version is
|
|
right
|
|
*/
|
|
relocation -= reloc_entry->addend;
|
|
#endif
|
|
reloc_entry->addend = 0;
|
|
}
|
|
else
|
|
{
|
|
reloc_entry->addend = relocation;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
reloc_entry->addend = 0;
|
|
}
|
|
|
|
/* FIXME: This overflow checking is incomplete, because the value
|
|
might have overflowed before we get here. For a correct check we
|
|
need to compute the value in a size larger than bitsize, but we
|
|
can't reasonably do that for a reloc the same size as a host
|
|
machine word.
|
|
FIXME: We should also do overflow checking on the result after
|
|
adding in the value contained in the object file. */
|
|
if (howto->complain_on_overflow != complain_overflow_dont)
|
|
{
|
|
bfd_vma check;
|
|
|
|
/* Get the value that will be used for the relocation, but
|
|
starting at bit position zero. */
|
|
if (howto->rightshift > howto->bitpos)
|
|
check = relocation >> (howto->rightshift - howto->bitpos);
|
|
else
|
|
check = relocation << (howto->bitpos - howto->rightshift);
|
|
switch (howto->complain_on_overflow)
|
|
{
|
|
case complain_overflow_signed:
|
|
{
|
|
/* Assumes two's complement. */
|
|
bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
|
|
bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
|
|
|
|
/* The above right shift is incorrect for a signed value.
|
|
Fix it up by forcing on the upper bits. */
|
|
if (howto->rightshift > howto->bitpos
|
|
&& (bfd_signed_vma) relocation < 0)
|
|
check |= ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1
|
|
>> (howto->rightshift - howto->bitpos)));
|
|
if ((bfd_signed_vma) check > reloc_signed_max
|
|
|| (bfd_signed_vma) check < reloc_signed_min)
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
break;
|
|
case complain_overflow_unsigned:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_unsigned_max =
|
|
(((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if ((bfd_vma) check > reloc_unsigned_max)
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
break;
|
|
case complain_overflow_bitfield:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if (((bfd_vma) check & ~reloc_bits) != 0
|
|
&& ((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
|
|
{
|
|
/* The above right shift is incorrect for a signed
|
|
value. See if turning on the upper bits fixes the
|
|
overflow. */
|
|
if (howto->rightshift > howto->bitpos
|
|
&& (bfd_signed_vma) relocation < 0)
|
|
{
|
|
check |= ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1
|
|
>> (howto->rightshift - howto->bitpos)));
|
|
if (((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
else
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
abort ();
|
|
}
|
|
}
|
|
|
|
/*
|
|
Either we are relocating all the way, or we don't want to apply
|
|
the relocation to the reloc entry (probably because there isn't
|
|
any room in the output format to describe addends to relocs)
|
|
*/
|
|
|
|
/* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
|
|
(OSF version 1.3, compiler version 3.11). It miscompiles the
|
|
following program:
|
|
|
|
struct str
|
|
{
|
|
unsigned int i0;
|
|
} s = { 0 };
|
|
|
|
int
|
|
main ()
|
|
{
|
|
unsigned long x;
|
|
|
|
x = 0x100000000;
|
|
x <<= (unsigned long) s.i0;
|
|
if (x == 0)
|
|
printf ("failed\n");
|
|
else
|
|
printf ("succeeded (%lx)\n", x);
|
|
}
|
|
*/
|
|
|
|
relocation >>= (bfd_vma) howto->rightshift;
|
|
|
|
/* Shift everything up to where it's going to be used */
|
|
|
|
relocation <<= (bfd_vma) howto->bitpos;
|
|
|
|
/* Wait for the day when all have the mask in them */
|
|
|
|
/* What we do:
|
|
i instruction to be left alone
|
|
o offset within instruction
|
|
r relocation offset to apply
|
|
S src mask
|
|
D dst mask
|
|
N ~dst mask
|
|
A part 1
|
|
B part 2
|
|
R result
|
|
|
|
Do this:
|
|
i i i i i o o o o o from bfd_get<size>
|
|
and S S S S S to get the size offset we want
|
|
+ r r r r r r r r r r to get the final value to place
|
|
and D D D D D to chop to right size
|
|
-----------------------
|
|
A A A A A
|
|
And this:
|
|
... i i i i i o o o o o from bfd_get<size>
|
|
and N N N N N get instruction
|
|
-----------------------
|
|
... B B B B B
|
|
|
|
And then:
|
|
B B B B B
|
|
or A A A A A
|
|
-----------------------
|
|
R R R R R R R R R R put into bfd_put<size>
|
|
*/
|
|
|
|
#define DOIT(x) \
|
|
x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
|
|
|
|
switch (howto->size)
|
|
{
|
|
case 0:
|
|
{
|
|
char x = bfd_get_8 (abfd, (char *) data + addr);
|
|
DOIT (x);
|
|
bfd_put_8 (abfd, x, (unsigned char *) data + addr);
|
|
}
|
|
break;
|
|
|
|
case 1:
|
|
if (relocation)
|
|
{
|
|
short x = bfd_get_16 (abfd, (bfd_byte *) data + addr);
|
|
DOIT (x);
|
|
bfd_put_16 (abfd, x, (unsigned char *) data + addr);
|
|
}
|
|
break;
|
|
case 2:
|
|
if (relocation)
|
|
{
|
|
long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
|
|
DOIT (x);
|
|
bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
|
|
}
|
|
break;
|
|
case -2:
|
|
{
|
|
long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
|
|
relocation = -relocation;
|
|
DOIT (x);
|
|
bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
|
|
}
|
|
break;
|
|
|
|
case 3:
|
|
/* Do nothing */
|
|
break;
|
|
|
|
case 4:
|
|
#ifdef BFD64
|
|
if (relocation)
|
|
{
|
|
bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + addr);
|
|
DOIT (x);
|
|
bfd_put_64 (abfd, x, (bfd_byte *) data + addr);
|
|
}
|
|
#else
|
|
abort ();
|
|
#endif
|
|
break;
|
|
default:
|
|
return bfd_reloc_other;
|
|
}
|
|
|
|
return flag;
|
|
}
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_install_relocation
|
|
|
|
SYNOPSIS
|
|
bfd_reloc_status_type
|
|
bfd_install_relocation
|
|
(bfd *abfd,
|
|
arelent *reloc_entry,
|
|
PTR data, bfd_vma data_start,
|
|
asection *input_section,
|
|
char **error_message);
|
|
|
|
DESCRIPTION
|
|
This looks remarkably like <<bfd_perform_relocation>>, except it
|
|
does not expect that the section contents have been filled in.
|
|
I.e., it's suitable for use when creating, rather than applying
|
|
a relocation.
|
|
|
|
For now, this function should be considered reserved for the
|
|
assembler.
|
|
|
|
*/
|
|
|
|
|
|
bfd_reloc_status_type
|
|
bfd_install_relocation (abfd, reloc_entry, data_start, data_start_offset,
|
|
input_section, error_message)
|
|
bfd *abfd;
|
|
arelent *reloc_entry;
|
|
PTR data_start;
|
|
bfd_vma data_start_offset;
|
|
asection *input_section;
|
|
char **error_message;
|
|
{
|
|
bfd_vma relocation;
|
|
bfd_reloc_status_type flag = bfd_reloc_ok;
|
|
bfd_size_type addr = reloc_entry->address;
|
|
bfd_vma output_base = 0;
|
|
const reloc_howto_type *howto = reloc_entry->howto;
|
|
asection *reloc_target_output_section;
|
|
asymbol *symbol;
|
|
bfd_byte *data;
|
|
|
|
symbol = *(reloc_entry->sym_ptr_ptr);
|
|
if (bfd_is_abs_section (symbol->section))
|
|
{
|
|
reloc_entry->address += input_section->output_offset;
|
|
return bfd_reloc_ok;
|
|
}
|
|
|
|
/* If there is a function supplied to handle this relocation type,
|
|
call it. It'll return `bfd_reloc_continue' if further processing
|
|
can be done. */
|
|
if (howto->special_function)
|
|
{
|
|
bfd_reloc_status_type cont;
|
|
/* XXX - The special_function calls haven't been fixed up to deal
|
|
with creating new relocations and section contents. */
|
|
cont = howto->special_function (abfd, reloc_entry, symbol,
|
|
/* XXX - Non-portable! */
|
|
((bfd_byte *) data_start
|
|
- data_start_offset),
|
|
input_section, abfd, error_message);
|
|
if (cont != bfd_reloc_continue)
|
|
return cont;
|
|
}
|
|
|
|
/* Is the address of the relocation really within the section? */
|
|
if (reloc_entry->address > input_section->_cooked_size)
|
|
return bfd_reloc_outofrange;
|
|
|
|
/* Work out which section the relocation is targetted at and the
|
|
initial relocation command value. */
|
|
|
|
/* Get symbol value. (Common symbols are special.) */
|
|
if (bfd_is_com_section (symbol->section))
|
|
relocation = 0;
|
|
else
|
|
relocation = symbol->value;
|
|
|
|
|
|
reloc_target_output_section = symbol->section->output_section;
|
|
|
|
/* Convert input-section-relative symbol value to absolute. */
|
|
if (howto->partial_inplace == false)
|
|
output_base = 0;
|
|
else
|
|
output_base = reloc_target_output_section->vma;
|
|
|
|
relocation += output_base + symbol->section->output_offset;
|
|
|
|
/* Add in supplied addend. */
|
|
relocation += reloc_entry->addend;
|
|
|
|
/* Here the variable relocation holds the final address of the
|
|
symbol we are relocating against, plus any addend. */
|
|
|
|
if (howto->pc_relative == true)
|
|
{
|
|
/* This is a PC relative relocation. We want to set RELOCATION
|
|
to the distance between the address of the symbol and the
|
|
location. RELOCATION is already the address of the symbol.
|
|
|
|
We start by subtracting the address of the section containing
|
|
the location.
|
|
|
|
If pcrel_offset is set, we must further subtract the position
|
|
of the location within the section. Some targets arrange for
|
|
the addend to be the negative of the position of the location
|
|
within the section; for example, i386-aout does this. For
|
|
i386-aout, pcrel_offset is false. Some other targets do not
|
|
include the position of the location; for example, m88kbcs,
|
|
or ELF. For those targets, pcrel_offset is true.
|
|
|
|
If we are producing relocateable output, then we must ensure
|
|
that this reloc will be correctly computed when the final
|
|
relocation is done. If pcrel_offset is false we want to wind
|
|
up with the negative of the location within the section,
|
|
which means we must adjust the existing addend by the change
|
|
in the location within the section. If pcrel_offset is true
|
|
we do not want to adjust the existing addend at all.
|
|
|
|
FIXME: This seems logical to me, but for the case of
|
|
producing relocateable output it is not what the code
|
|
actually does. I don't want to change it, because it seems
|
|
far too likely that something will break. */
|
|
|
|
relocation -=
|
|
input_section->output_section->vma + input_section->output_offset;
|
|
|
|
if (howto->pcrel_offset == true && howto->partial_inplace == true)
|
|
relocation -= reloc_entry->address;
|
|
}
|
|
|
|
if (howto->partial_inplace == false)
|
|
{
|
|
/* This is a partial relocation, and we want to apply the relocation
|
|
to the reloc entry rather than the raw data. Modify the reloc
|
|
inplace to reflect what we now know. */
|
|
reloc_entry->addend = relocation;
|
|
reloc_entry->address += input_section->output_offset;
|
|
return flag;
|
|
}
|
|
else
|
|
{
|
|
/* This is a partial relocation, but inplace, so modify the
|
|
reloc record a bit.
|
|
|
|
If we've relocated with a symbol with a section, change
|
|
into a ref to the section belonging to the symbol. */
|
|
|
|
reloc_entry->address += input_section->output_offset;
|
|
|
|
/* WTF?? */
|
|
if (abfd->xvec->flavour == bfd_target_coff_flavour
|
|
&& strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
|
|
&& strcmp (abfd->xvec->name, "coff-Intel-little") != 0
|
|
&& strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
|
|
{
|
|
#if 1
|
|
/* For m68k-coff, the addend was being subtracted twice during
|
|
relocation with -r. Removing the line below this comment
|
|
fixes that problem; see PR 2953.
|
|
|
|
However, Ian wrote the following, regarding removing the line below,
|
|
which explains why it is still enabled: --djm
|
|
|
|
If you put a patch like that into BFD you need to check all the COFF
|
|
linkers. I am fairly certain that patch will break coff-i386 (e.g.,
|
|
SCO); see coff_i386_reloc in coff-i386.c where I worked around the
|
|
problem in a different way. There may very well be a reason that the
|
|
code works as it does.
|
|
|
|
Hmmm. The first obvious point is that bfd_install_relocation should
|
|
not have any tests that depend upon the flavour. It's seem like
|
|
entirely the wrong place for such a thing. The second obvious point
|
|
is that the current code ignores the reloc addend when producing
|
|
relocateable output for COFF. That's peculiar. In fact, I really
|
|
have no idea what the point of the line you want to remove is.
|
|
|
|
A typical COFF reloc subtracts the old value of the symbol and adds in
|
|
the new value to the location in the object file (if it's a pc
|
|
relative reloc it adds the difference between the symbol value and the
|
|
location). When relocating we need to preserve that property.
|
|
|
|
BFD handles this by setting the addend to the negative of the old
|
|
value of the symbol. Unfortunately it handles common symbols in a
|
|
non-standard way (it doesn't subtract the old value) but that's a
|
|
different story (we can't change it without losing backward
|
|
compatibility with old object files) (coff-i386 does subtract the old
|
|
value, to be compatible with existing coff-i386 targets, like SCO).
|
|
|
|
So everything works fine when not producing relocateable output. When
|
|
we are producing relocateable output, logically we should do exactly
|
|
what we do when not producing relocateable output. Therefore, your
|
|
patch is correct. In fact, it should probably always just set
|
|
reloc_entry->addend to 0 for all cases, since it is, in fact, going to
|
|
add the value into the object file. This won't hurt the COFF code,
|
|
which doesn't use the addend; I'm not sure what it will do to other
|
|
formats (the thing to check for would be whether any formats both use
|
|
the addend and set partial_inplace).
|
|
|
|
When I wanted to make coff-i386 produce relocateable output, I ran
|
|
into the problem that you are running into: I wanted to remove that
|
|
line. Rather than risk it, I made the coff-i386 relocs use a special
|
|
function; it's coff_i386_reloc in coff-i386.c. The function
|
|
specifically adds the addend field into the object file, knowing that
|
|
bfd_install_relocation is not going to. If you remove that line, then
|
|
coff-i386.c will wind up adding the addend field in twice. It's
|
|
trivial to fix; it just needs to be done.
|
|
|
|
The problem with removing the line is just that it may break some
|
|
working code. With BFD it's hard to be sure of anything. The right
|
|
way to deal with this is simply to build and test at least all the
|
|
supported COFF targets. It should be straightforward if time and disk
|
|
space consuming. For each target:
|
|
1) build the linker
|
|
2) generate some executable, and link it using -r (I would
|
|
probably use paranoia.o and link against newlib/libc.a, which
|
|
for all the supported targets would be available in
|
|
/usr/cygnus/progressive/H-host/target/lib/libc.a).
|
|
3) make the change to reloc.c
|
|
4) rebuild the linker
|
|
5) repeat step 2
|
|
6) if the resulting object files are the same, you have at least
|
|
made it no worse
|
|
7) if they are different you have to figure out which version is
|
|
right
|
|
*/
|
|
relocation -= reloc_entry->addend;
|
|
#endif
|
|
reloc_entry->addend = 0;
|
|
}
|
|
else
|
|
{
|
|
reloc_entry->addend = relocation;
|
|
}
|
|
}
|
|
|
|
/* FIXME: This overflow checking is incomplete, because the value
|
|
might have overflowed before we get here. For a correct check we
|
|
need to compute the value in a size larger than bitsize, but we
|
|
can't reasonably do that for a reloc the same size as a host
|
|
machine word.
|
|
|
|
FIXME: We should also do overflow checking on the result after
|
|
adding in the value contained in the object file. */
|
|
if (howto->complain_on_overflow != complain_overflow_dont)
|
|
{
|
|
bfd_vma check;
|
|
|
|
/* Get the value that will be used for the relocation, but
|
|
starting at bit position zero. */
|
|
if (howto->rightshift > howto->bitpos)
|
|
check = relocation >> (howto->rightshift - howto->bitpos);
|
|
else
|
|
check = relocation << (howto->bitpos - howto->rightshift);
|
|
switch (howto->complain_on_overflow)
|
|
{
|
|
case complain_overflow_signed:
|
|
{
|
|
/* Assumes two's complement. */
|
|
bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
|
|
bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
|
|
|
|
/* The above right shift is incorrect for a signed value.
|
|
Fix it up by forcing on the upper bits. */
|
|
if (howto->rightshift > howto->bitpos
|
|
&& (bfd_signed_vma) relocation < 0)
|
|
check |= ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1
|
|
>> (howto->rightshift - howto->bitpos)));
|
|
if ((bfd_signed_vma) check > reloc_signed_max
|
|
|| (bfd_signed_vma) check < reloc_signed_min)
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
break;
|
|
case complain_overflow_unsigned:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_unsigned_max =
|
|
(((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if ((bfd_vma) check > reloc_unsigned_max)
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
break;
|
|
case complain_overflow_bitfield:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if (((bfd_vma) check & ~reloc_bits) != 0
|
|
&& ((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
|
|
{
|
|
/* The above right shift is incorrect for a signed
|
|
value. See if turning on the upper bits fixes the
|
|
overflow. */
|
|
if (howto->rightshift > howto->bitpos
|
|
&& (bfd_signed_vma) relocation < 0)
|
|
{
|
|
check |= ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1
|
|
>> (howto->rightshift - howto->bitpos)));
|
|
if (((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
else
|
|
flag = bfd_reloc_overflow;
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
abort ();
|
|
}
|
|
}
|
|
|
|
/*
|
|
Either we are relocating all the way, or we don't want to apply
|
|
the relocation to the reloc entry (probably because there isn't
|
|
any room in the output format to describe addends to relocs)
|
|
*/
|
|
|
|
/* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
|
|
(OSF version 1.3, compiler version 3.11). It miscompiles the
|
|
following program:
|
|
|
|
struct str
|
|
{
|
|
unsigned int i0;
|
|
} s = { 0 };
|
|
|
|
int
|
|
main ()
|
|
{
|
|
unsigned long x;
|
|
|
|
x = 0x100000000;
|
|
x <<= (unsigned long) s.i0;
|
|
if (x == 0)
|
|
printf ("failed\n");
|
|
else
|
|
printf ("succeeded (%lx)\n", x);
|
|
}
|
|
*/
|
|
|
|
relocation >>= (bfd_vma) howto->rightshift;
|
|
|
|
/* Shift everything up to where it's going to be used */
|
|
|
|
relocation <<= (bfd_vma) howto->bitpos;
|
|
|
|
/* Wait for the day when all have the mask in them */
|
|
|
|
/* What we do:
|
|
i instruction to be left alone
|
|
o offset within instruction
|
|
r relocation offset to apply
|
|
S src mask
|
|
D dst mask
|
|
N ~dst mask
|
|
A part 1
|
|
B part 2
|
|
R result
|
|
|
|
Do this:
|
|
i i i i i o o o o o from bfd_get<size>
|
|
and S S S S S to get the size offset we want
|
|
+ r r r r r r r r r r to get the final value to place
|
|
and D D D D D to chop to right size
|
|
-----------------------
|
|
A A A A A
|
|
And this:
|
|
... i i i i i o o o o o from bfd_get<size>
|
|
and N N N N N get instruction
|
|
-----------------------
|
|
... B B B B B
|
|
|
|
And then:
|
|
B B B B B
|
|
or A A A A A
|
|
-----------------------
|
|
R R R R R R R R R R put into bfd_put<size>
|
|
*/
|
|
|
|
#define DOIT(x) \
|
|
x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
|
|
|
|
data = (bfd_byte *) data_start + (addr - data_start_offset);
|
|
|
|
switch (howto->size)
|
|
{
|
|
case 0:
|
|
{
|
|
char x = bfd_get_8 (abfd, (char *) data);
|
|
DOIT (x);
|
|
bfd_put_8 (abfd, x, (unsigned char *) data);
|
|
}
|
|
break;
|
|
|
|
case 1:
|
|
if (relocation)
|
|
{
|
|
short x = bfd_get_16 (abfd, (bfd_byte *) data);
|
|
DOIT (x);
|
|
bfd_put_16 (abfd, x, (unsigned char *) data);
|
|
}
|
|
break;
|
|
case 2:
|
|
if (relocation)
|
|
{
|
|
long x = bfd_get_32 (abfd, (bfd_byte *) data);
|
|
DOIT (x);
|
|
bfd_put_32 (abfd, x, (bfd_byte *) data);
|
|
}
|
|
break;
|
|
case -2:
|
|
{
|
|
long x = bfd_get_32 (abfd, (bfd_byte *) data);
|
|
relocation = -relocation;
|
|
DOIT (x);
|
|
bfd_put_32 (abfd, x, (bfd_byte *) data);
|
|
}
|
|
break;
|
|
|
|
case 3:
|
|
/* Do nothing */
|
|
break;
|
|
|
|
case 4:
|
|
if (relocation)
|
|
{
|
|
bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data);
|
|
DOIT (x);
|
|
bfd_put_64 (abfd, x, (bfd_byte *) data);
|
|
}
|
|
break;
|
|
default:
|
|
return bfd_reloc_other;
|
|
}
|
|
|
|
return flag;
|
|
}
|
|
|
|
/* This relocation routine is used by some of the backend linkers.
|
|
They do not construct asymbol or arelent structures, so there is no
|
|
reason for them to use bfd_perform_relocation. Also,
|
|
bfd_perform_relocation is so hacked up it is easier to write a new
|
|
function than to try to deal with it.
|
|
|
|
This routine does a final relocation. It should not be used when
|
|
generating relocateable output.
|
|
|
|
FIXME: This routine ignores any special_function in the HOWTO,
|
|
since the existing special_function values have been written for
|
|
bfd_perform_relocation.
|
|
|
|
HOWTO is the reloc howto information.
|
|
INPUT_BFD is the BFD which the reloc applies to.
|
|
INPUT_SECTION is the section which the reloc applies to.
|
|
CONTENTS is the contents of the section.
|
|
ADDRESS is the address of the reloc within INPUT_SECTION.
|
|
VALUE is the value of the symbol the reloc refers to.
|
|
ADDEND is the addend of the reloc. */
|
|
|
|
bfd_reloc_status_type
|
|
_bfd_final_link_relocate (howto, input_bfd, input_section, contents, address,
|
|
value, addend)
|
|
const reloc_howto_type *howto;
|
|
bfd *input_bfd;
|
|
asection *input_section;
|
|
bfd_byte *contents;
|
|
bfd_vma address;
|
|
bfd_vma value;
|
|
bfd_vma addend;
|
|
{
|
|
bfd_vma relocation;
|
|
|
|
/* Sanity check the address. */
|
|
if (address > input_section->_cooked_size)
|
|
return bfd_reloc_outofrange;
|
|
|
|
/* This function assumes that we are dealing with a basic relocation
|
|
against a symbol. We want to compute the value of the symbol to
|
|
relocate to. This is just VALUE, the value of the symbol, plus
|
|
ADDEND, any addend associated with the reloc. */
|
|
relocation = value + addend;
|
|
|
|
/* If the relocation is PC relative, we want to set RELOCATION to
|
|
the distance between the symbol (currently in RELOCATION) and the
|
|
location we are relocating. Some targets (e.g., i386-aout)
|
|
arrange for the contents of the section to be the negative of the
|
|
offset of the location within the section; for such targets
|
|
pcrel_offset is false. Other targets (e.g., m88kbcs or ELF)
|
|
simply leave the contents of the section as zero; for such
|
|
targets pcrel_offset is true. If pcrel_offset is false we do not
|
|
need to subtract out the offset of the location within the
|
|
section (which is just ADDRESS). */
|
|
if (howto->pc_relative)
|
|
{
|
|
relocation -= (input_section->output_section->vma
|
|
+ input_section->output_offset);
|
|
if (howto->pcrel_offset)
|
|
relocation -= address;
|
|
}
|
|
|
|
return _bfd_relocate_contents (howto, input_bfd, relocation,
|
|
contents + address);
|
|
}
|
|
|
|
/* Relocate a given location using a given value and howto. */
|
|
|
|
bfd_reloc_status_type
|
|
_bfd_relocate_contents (howto, input_bfd, relocation, location)
|
|
const reloc_howto_type *howto;
|
|
bfd *input_bfd;
|
|
bfd_vma relocation;
|
|
bfd_byte *location;
|
|
{
|
|
int size;
|
|
bfd_vma x;
|
|
boolean overflow;
|
|
|
|
/* If the size is negative, negate RELOCATION. This isn't very
|
|
general. */
|
|
if (howto->size < 0)
|
|
relocation = -relocation;
|
|
|
|
/* Get the value we are going to relocate. */
|
|
size = bfd_get_reloc_size (howto);
|
|
switch (size)
|
|
{
|
|
default:
|
|
case 0:
|
|
abort ();
|
|
case 1:
|
|
x = bfd_get_8 (input_bfd, location);
|
|
break;
|
|
case 2:
|
|
x = bfd_get_16 (input_bfd, location);
|
|
break;
|
|
case 4:
|
|
x = bfd_get_32 (input_bfd, location);
|
|
break;
|
|
case 8:
|
|
#ifdef BFD64
|
|
x = bfd_get_64 (input_bfd, location);
|
|
#else
|
|
abort ();
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
/* Check for overflow. FIXME: We may drop bits during the addition
|
|
which we don't check for. We must either check at every single
|
|
operation, which would be tedious, or we must do the computations
|
|
in a type larger than bfd_vma, which would be inefficient. */
|
|
overflow = false;
|
|
if (howto->complain_on_overflow != complain_overflow_dont)
|
|
{
|
|
bfd_vma check;
|
|
bfd_signed_vma signed_check;
|
|
bfd_vma add;
|
|
bfd_signed_vma signed_add;
|
|
|
|
if (howto->rightshift == 0)
|
|
{
|
|
check = relocation;
|
|
signed_check = (bfd_signed_vma) relocation;
|
|
}
|
|
else
|
|
{
|
|
/* Drop unwanted bits from the value we are relocating to. */
|
|
check = relocation >> howto->rightshift;
|
|
|
|
/* If this is a signed value, the rightshift just dropped
|
|
leading 1 bits (assuming twos complement). */
|
|
if ((bfd_signed_vma) relocation >= 0)
|
|
signed_check = check;
|
|
else
|
|
signed_check = (check
|
|
| ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1 >> howto->rightshift)));
|
|
}
|
|
|
|
/* Get the value from the object file. */
|
|
add = x & howto->src_mask;
|
|
|
|
/* Get the value from the object file with an appropriate sign.
|
|
The expression involving howto->src_mask isolates the upper
|
|
bit of src_mask. If that bit is set in the value we are
|
|
adding, it is negative, and we subtract out that number times
|
|
two. If src_mask includes the highest possible bit, then we
|
|
can not get the upper bit, but that does not matter since
|
|
signed_add needs no adjustment to become negative in that
|
|
case. */
|
|
signed_add = add;
|
|
if ((add & (((~howto->src_mask) >> 1) & howto->src_mask)) != 0)
|
|
signed_add -= (((~howto->src_mask) >> 1) & howto->src_mask) << 1;
|
|
|
|
/* Add the value from the object file, shifted so that it is a
|
|
straight number. */
|
|
if (howto->bitpos == 0)
|
|
{
|
|
check += add;
|
|
signed_check += signed_add;
|
|
}
|
|
else
|
|
{
|
|
check += add >> howto->bitpos;
|
|
|
|
/* For the signed case we use ADD, rather than SIGNED_ADD,
|
|
to avoid warnings from SVR4 cc. This is OK since we
|
|
explictly handle the sign bits. */
|
|
if (signed_add >= 0)
|
|
signed_check += add >> howto->bitpos;
|
|
else
|
|
signed_check += ((add >> howto->bitpos)
|
|
| ((bfd_vma) - 1
|
|
& ~((bfd_vma) - 1 >> howto->bitpos)));
|
|
}
|
|
|
|
switch (howto->complain_on_overflow)
|
|
{
|
|
case complain_overflow_signed:
|
|
{
|
|
/* Assumes two's complement. */
|
|
bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
|
|
bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
|
|
|
|
if (signed_check > reloc_signed_max
|
|
|| signed_check < reloc_signed_min)
|
|
overflow = true;
|
|
}
|
|
break;
|
|
case complain_overflow_unsigned:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_unsigned_max =
|
|
(((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if (check > reloc_unsigned_max)
|
|
overflow = true;
|
|
}
|
|
break;
|
|
case complain_overflow_bitfield:
|
|
{
|
|
/* Assumes two's complement. This expression avoids
|
|
overflow if howto->bitsize is the number of bits in
|
|
bfd_vma. */
|
|
bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
|
|
|
|
if ((check & ~reloc_bits) != 0
|
|
&& (((bfd_vma) signed_check & ~reloc_bits)
|
|
!= (-1 & ~reloc_bits)))
|
|
overflow = true;
|
|
}
|
|
break;
|
|
default:
|
|
abort ();
|
|
}
|
|
}
|
|
|
|
/* Put RELOCATION in the right bits. */
|
|
relocation >>= (bfd_vma) howto->rightshift;
|
|
relocation <<= (bfd_vma) howto->bitpos;
|
|
|
|
/* Add RELOCATION to the right bits of X. */
|
|
x = ((x & ~howto->dst_mask)
|
|
| (((x & howto->src_mask) + relocation) & howto->dst_mask));
|
|
|
|
/* Put the relocated value back in the object file. */
|
|
switch (size)
|
|
{
|
|
default:
|
|
case 0:
|
|
abort ();
|
|
case 1:
|
|
bfd_put_8 (input_bfd, x, location);
|
|
break;
|
|
case 2:
|
|
bfd_put_16 (input_bfd, x, location);
|
|
break;
|
|
case 4:
|
|
bfd_put_32 (input_bfd, x, location);
|
|
break;
|
|
case 8:
|
|
#ifdef BFD64
|
|
bfd_put_64 (input_bfd, x, location);
|
|
#else
|
|
abort ();
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
return overflow ? bfd_reloc_overflow : bfd_reloc_ok;
|
|
}
|
|
|
|
/*
|
|
DOCDD
|
|
INODE
|
|
howto manager, , typedef arelent, Relocations
|
|
|
|
SECTION
|
|
The howto manager
|
|
|
|
When an application wants to create a relocation, but doesn't
|
|
know what the target machine might call it, it can find out by
|
|
using this bit of code.
|
|
|
|
*/
|
|
|
|
/*
|
|
TYPEDEF
|
|
bfd_reloc_code_type
|
|
|
|
DESCRIPTION
|
|
The insides of a reloc code. The idea is that, eventually, there
|
|
will be one enumerator for every type of relocation we ever do.
|
|
Pass one of these values to <<bfd_reloc_type_lookup>>, and it'll
|
|
return a howto pointer.
|
|
|
|
This does mean that the application must determine the correct
|
|
enumerator value; you can't get a howto pointer from a random set
|
|
of attributes.
|
|
|
|
SENUM
|
|
bfd_reloc_code_real
|
|
|
|
ENUM
|
|
BFD_RELOC_64
|
|
ENUMX
|
|
BFD_RELOC_32
|
|
ENUMX
|
|
BFD_RELOC_26
|
|
ENUMX
|
|
BFD_RELOC_16
|
|
ENUMX
|
|
BFD_RELOC_14
|
|
ENUMX
|
|
BFD_RELOC_8
|
|
ENUMDOC
|
|
Basic absolute relocations of N bits.
|
|
|
|
ENUM
|
|
BFD_RELOC_64_PCREL
|
|
ENUMX
|
|
BFD_RELOC_32_PCREL
|
|
ENUMX
|
|
BFD_RELOC_24_PCREL
|
|
ENUMX
|
|
BFD_RELOC_16_PCREL
|
|
ENUMX
|
|
BFD_RELOC_12_PCREL
|
|
ENUMX
|
|
BFD_RELOC_8_PCREL
|
|
ENUMDOC
|
|
PC-relative relocations. Sometimes these are relative to the address
|
|
of the relocation itself; sometimes they are relative to the start of
|
|
the section containing the relocation. It depends on the specific target.
|
|
|
|
The 24-bit relocation is used in some Intel 960 configurations.
|
|
|
|
ENUM
|
|
BFD_RELOC_32_BASEREL
|
|
ENUMX
|
|
BFD_RELOC_16_BASEREL
|
|
ENUMX
|
|
BFD_RELOC_8_BASEREL
|
|
ENUMDOC
|
|
Linkage-table relative.
|
|
|
|
ENUM
|
|
BFD_RELOC_8_FFnn
|
|
ENUMDOC
|
|
Absolute 8-bit relocation, but used to form an address like 0xFFnn.
|
|
|
|
ENUM
|
|
BFD_RELOC_32_PCREL_S2
|
|
ENUMX
|
|
BFD_RELOC_16_PCREL_S2
|
|
ENUMX
|
|
BFD_RELOC_23_PCREL_S2
|
|
ENUMDOC
|
|
These PC-relative relocations are stored as word displacements --
|
|
i.e., byte displacements shifted right two bits. The 30-bit word
|
|
displacement (<<32_PCREL_S2>> -- 32 bits, shifted 2) is used on the
|
|
SPARC. (SPARC tools generally refer to this as <<WDISP30>>.) The
|
|
signed 16-bit displacement is used on the MIPS, and the 23-bit
|
|
displacement is used on the Alpha.
|
|
|
|
ENUM
|
|
BFD_RELOC_HI22
|
|
ENUMX
|
|
BFD_RELOC_LO10
|
|
ENUMDOC
|
|
High 22 bits and low 10 bits of 32-bit value, placed into lower bits of
|
|
the target word. These are used on the SPARC.
|
|
|
|
ENUM
|
|
BFD_RELOC_GPREL16
|
|
ENUMX
|
|
BFD_RELOC_GPREL32
|
|
ENUMDOC
|
|
For systems that allocate a Global Pointer register, these are
|
|
displacements off that register. These relocation types are
|
|
handled specially, because the value the register will have is
|
|
decided relatively late.
|
|
|
|
|
|
ENUM
|
|
BFD_RELOC_I960_CALLJ
|
|
ENUMDOC
|
|
Reloc types used for i960/b.out.
|
|
|
|
ENUM
|
|
BFD_RELOC_NONE
|
|
ENUMX
|
|
BFD_RELOC_SPARC_WDISP22
|
|
ENUMX
|
|
BFD_RELOC_SPARC22
|
|
ENUMX
|
|
BFD_RELOC_SPARC13
|
|
ENUMX
|
|
BFD_RELOC_SPARC_GOT10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_GOT13
|
|
ENUMX
|
|
BFD_RELOC_SPARC_GOT22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_PC10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_PC22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_WPLT30
|
|
ENUMX
|
|
BFD_RELOC_SPARC_COPY
|
|
ENUMX
|
|
BFD_RELOC_SPARC_GLOB_DAT
|
|
ENUMX
|
|
BFD_RELOC_SPARC_JMP_SLOT
|
|
ENUMX
|
|
BFD_RELOC_SPARC_RELATIVE
|
|
ENUMX
|
|
BFD_RELOC_SPARC_UA32
|
|
ENUMDOC
|
|
SPARC ELF relocations. There is probably some overlap with other
|
|
relocation types already defined.
|
|
|
|
ENUM
|
|
BFD_RELOC_SPARC_BASE13
|
|
ENUMX
|
|
BFD_RELOC_SPARC_BASE22
|
|
ENUMDOC
|
|
I think these are specific to SPARC a.out (e.g., Sun 4).
|
|
|
|
ENUMEQ
|
|
BFD_RELOC_SPARC_64
|
|
BFD_RELOC_64
|
|
ENUMX
|
|
BFD_RELOC_SPARC_10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_11
|
|
ENUMX
|
|
BFD_RELOC_SPARC_OLO10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_HH22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_HM10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_LM22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_PC_HH22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_PC_HM10
|
|
ENUMX
|
|
BFD_RELOC_SPARC_PC_LM22
|
|
ENUMX
|
|
BFD_RELOC_SPARC_WDISP16
|
|
ENUMX
|
|
BFD_RELOC_SPARC_WDISP19
|
|
ENUMX
|
|
BFD_RELOC_SPARC_GLOB_JMP
|
|
ENUMX
|
|
BFD_RELOC_SPARC_LO7
|
|
ENUMDOC
|
|
Some relocations we're using for SPARC V9 -- subject to change.
|
|
|
|
ENUM
|
|
BFD_RELOC_ALPHA_GPDISP_HI16
|
|
ENUMDOC
|
|
Alpha ECOFF relocations. Some of these treat the symbol or "addend"
|
|
in some special way.
|
|
For GPDISP_HI16 ("gpdisp") relocations, the symbol is ignored when
|
|
writing; when reading, it will be the absolute section symbol. The
|
|
addend is the displacement in bytes of the "lda" instruction from
|
|
the "ldah" instruction (which is at the address of this reloc).
|
|
ENUM
|
|
BFD_RELOC_ALPHA_GPDISP_LO16
|
|
ENUMDOC
|
|
For GPDISP_LO16 ("ignore") relocations, the symbol is handled as
|
|
with GPDISP_HI16 relocs. The addend is ignored when writing the
|
|
relocations out, and is filled in with the file's GP value on
|
|
reading, for convenience.
|
|
|
|
ENUM
|
|
BFD_RELOC_ALPHA_LITERAL
|
|
ENUMX
|
|
BFD_RELOC_ALPHA_LITUSE
|
|
ENUMDOC
|
|
The Alpha LITERAL/LITUSE relocs are produced by a symbol reference;
|
|
the assembler turns it into a LDQ instruction to load the address of
|
|
the symbol, and then fills in a register in the real instruction.
|
|
|
|
The LITERAL reloc, at the LDQ instruction, refers to the .lita
|
|
section symbol. The addend is ignored when writing, but is filled
|
|
in with the file's GP value on reading, for convenience, as with the
|
|
GPDISP_LO16 reloc.
|
|
|
|
The LITUSE reloc, on the instruction using the loaded address, gives
|
|
information to the linker that it might be able to use to optimize
|
|
away some literal section references. The symbol is ignored (read
|
|
as the absolute section symbol), and the "addend" indicates the type
|
|
of instruction using the register:
|
|
1 - "memory" fmt insn
|
|
2 - byte-manipulation (byte offset reg)
|
|
3 - jsr (target of branch)
|
|
|
|
The GNU linker currently doesn't do any of this optimizing.
|
|
|
|
ENUM
|
|
BFD_RELOC_ALPHA_HINT
|
|
ENUMDOC
|
|
The HINT relocation indicates a value that should be filled into the
|
|
"hint" field of a jmp/jsr/ret instruction, for possible branch-
|
|
prediction logic which may be provided on some processors.
|
|
|
|
ENUM
|
|
BFD_RELOC_MIPS_JMP
|
|
ENUMDOC
|
|
Bits 27..2 of the relocation address shifted right 2 bits;
|
|
simple reloc otherwise.
|
|
|
|
ENUM
|
|
BFD_RELOC_HI16
|
|
ENUMDOC
|
|
High 16 bits of 32-bit value; simple reloc.
|
|
ENUM
|
|
BFD_RELOC_HI16_S
|
|
ENUMDOC
|
|
High 16 bits of 32-bit value but the low 16 bits will be sign
|
|
extended and added to form the final result. If the low 16
|
|
bits form a negative number, we need to add one to the high value
|
|
to compensate for the borrow when the low bits are added.
|
|
ENUM
|
|
BFD_RELOC_LO16
|
|
ENUMDOC
|
|
Low 16 bits.
|
|
ENUM
|
|
BFD_RELOC_PCREL_HI16_S
|
|
ENUMDOC
|
|
Like BFD_RELOC_HI16_S, but PC relative.
|
|
ENUM
|
|
BFD_RELOC_PCREL_LO16
|
|
ENUMDOC
|
|
Like BFD_RELOC_LO16, but PC relative.
|
|
|
|
ENUMEQ
|
|
BFD_RELOC_MIPS_GPREL
|
|
BFD_RELOC_GPREL16
|
|
ENUMDOC
|
|
Relocation relative to the global pointer.
|
|
|
|
ENUM
|
|
BFD_RELOC_MIPS_LITERAL
|
|
ENUMDOC
|
|
Relocation against a MIPS literal section.
|
|
|
|
ENUM
|
|
BFD_RELOC_MIPS_GOT16
|
|
ENUMX
|
|
BFD_RELOC_MIPS_CALL16
|
|
ENUMEQX
|
|
BFD_RELOC_MIPS_GPREL32
|
|
BFD_RELOC_GPREL32
|
|
ENUMDOC
|
|
MIPS ELF relocations.
|
|
|
|
ENUM
|
|
BFD_RELOC_386_GOT32
|
|
ENUMX
|
|
BFD_RELOC_386_PLT32
|
|
ENUMX
|
|
BFD_RELOC_386_COPY
|
|
ENUMX
|
|
BFD_RELOC_386_GLOB_DAT
|
|
ENUMX
|
|
BFD_RELOC_386_JUMP_SLOT
|
|
ENUMX
|
|
BFD_RELOC_386_RELATIVE
|
|
ENUMX
|
|
BFD_RELOC_386_GOTOFF
|
|
ENUMX
|
|
BFD_RELOC_386_GOTPC
|
|
ENUMDOC
|
|
i386/elf relocations
|
|
|
|
ENUM
|
|
BFD_RELOC_NS32K_IMM_8
|
|
ENUMX
|
|
BFD_RELOC_NS32K_IMM_16
|
|
ENUMX
|
|
BFD_RELOC_NS32K_IMM_32
|
|
ENUMX
|
|
BFD_RELOC_NS32K_IMM_8_PCREL
|
|
ENUMX
|
|
BFD_RELOC_NS32K_IMM_16_PCREL
|
|
ENUMX
|
|
BFD_RELOC_NS32K_IMM_32_PCREL
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_8
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_16
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_32
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_8_PCREL
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_16_PCREL
|
|
ENUMX
|
|
BFD_RELOC_NS32K_DISP_32_PCREL
|
|
ENUMDOC
|
|
ns32k relocations
|
|
|
|
ENUM
|
|
BFD_RELOC_PPC_B26
|
|
ENUMDOC
|
|
PowerPC/POWER (RS/6000) relocs.
|
|
26 bit relative branch. Low two bits must be zero. High 24
|
|
bits installed in bits 6 through 29 of instruction.
|
|
ENUM
|
|
BFD_RELOC_PPC_BA26
|
|
ENUMDOC
|
|
26 bit absolute branch, like BFD_RELOC_PPC_B26 but absolute.
|
|
ENUM
|
|
BFD_RELOC_PPC_TOC16
|
|
ENUMDOC
|
|
16 bit TOC relative reference.
|
|
|
|
ENUM
|
|
BFD_RELOC_CTOR
|
|
ENUMDOC
|
|
The type of reloc used to build a contructor table - at the moment
|
|
probably a 32 bit wide absolute relocation, but the target can choose.
|
|
It generally does map to one of the other relocation types.
|
|
|
|
ENUM
|
|
BFD_RELOC_ARM_PCREL_BRANCH
|
|
ENUMDOC
|
|
ARM 26 bit pc-relative branch. The lowest two bits must be zero and are
|
|
not stored in the instruction.
|
|
ENUM
|
|
BFD_RELOC_ARM_IMMEDIATE
|
|
ENUMX
|
|
BFD_RELOC_ARM_OFFSET_IMM
|
|
ENUMX
|
|
BFD_RELOC_ARM_SHIFT_IMM
|
|
ENUMX
|
|
BFD_RELOC_ARM_SWI
|
|
ENUMX
|
|
BFD_RELOC_ARM_MULTI
|
|
ENUMX
|
|
BFD_RELOC_ARM_CP_OFF_IMM
|
|
ENUMDOC
|
|
These relocs are only used within the ARM assembler. They are not
|
|
(at present) written to any object files.
|
|
|
|
ENDSENUM
|
|
BFD_RELOC_UNUSED
|
|
|
|
CODE_FRAGMENT
|
|
.
|
|
.typedef enum bfd_reloc_code_real bfd_reloc_code_real_type;
|
|
*/
|
|
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_reloc_type_lookup
|
|
|
|
SYNOPSIS
|
|
const struct reloc_howto_struct *
|
|
bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
|
|
|
|
DESCRIPTION
|
|
Return a pointer to a howto structure which, when
|
|
invoked, will perform the relocation @var{code} on data from the
|
|
architecture noted.
|
|
|
|
*/
|
|
|
|
|
|
const struct reloc_howto_struct *
|
|
bfd_reloc_type_lookup (abfd, code)
|
|
bfd *abfd;
|
|
bfd_reloc_code_real_type code;
|
|
{
|
|
return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
|
|
}
|
|
|
|
static reloc_howto_type bfd_howto_32 =
|
|
HOWTO (0, 00, 2, 32, false, 0, complain_overflow_bitfield, 0, "VRT32", false, 0xffffffff, 0xffffffff, true);
|
|
|
|
|
|
/*
|
|
INTERNAL_FUNCTION
|
|
bfd_default_reloc_type_lookup
|
|
|
|
SYNOPSIS
|
|
const struct reloc_howto_struct *bfd_default_reloc_type_lookup
|
|
(bfd *abfd, bfd_reloc_code_real_type code);
|
|
|
|
DESCRIPTION
|
|
Provides a default relocation lookup routine for any architecture.
|
|
|
|
|
|
*/
|
|
|
|
const struct reloc_howto_struct *
|
|
bfd_default_reloc_type_lookup (abfd, code)
|
|
bfd *abfd;
|
|
bfd_reloc_code_real_type code;
|
|
{
|
|
switch (code)
|
|
{
|
|
case BFD_RELOC_CTOR:
|
|
/* The type of reloc used in a ctor, which will be as wide as the
|
|
address - so either a 64, 32, or 16 bitter. */
|
|
switch (bfd_get_arch_info (abfd)->bits_per_address)
|
|
{
|
|
case 64:
|
|
BFD_FAIL ();
|
|
case 32:
|
|
return &bfd_howto_32;
|
|
case 16:
|
|
BFD_FAIL ();
|
|
default:
|
|
BFD_FAIL ();
|
|
}
|
|
default:
|
|
BFD_FAIL ();
|
|
}
|
|
return (const struct reloc_howto_struct *) NULL;
|
|
}
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_get_reloc_code_name
|
|
|
|
SYNOPSIS
|
|
const char *bfd_get_reloc_code_name (bfd_reloc_code_real_type code);
|
|
|
|
DESCRIPTION
|
|
Provides a printable name for the supplied relocation code.
|
|
Useful mainly for printing error messages.
|
|
*/
|
|
|
|
const char *
|
|
bfd_get_reloc_code_name (code)
|
|
bfd_reloc_code_real_type code;
|
|
{
|
|
if (code > BFD_RELOC_UNUSED)
|
|
return 0;
|
|
return bfd_reloc_code_real_names[(int)code];
|
|
}
|
|
|
|
/*
|
|
INTERNAL_FUNCTION
|
|
bfd_generic_relax_section
|
|
|
|
SYNOPSIS
|
|
boolean bfd_generic_relax_section
|
|
(bfd *abfd,
|
|
asection *section,
|
|
struct bfd_link_info *,
|
|
boolean *);
|
|
|
|
DESCRIPTION
|
|
Provides default handling for relaxing for back ends which
|
|
don't do relaxing -- i.e., does nothing.
|
|
*/
|
|
|
|
/*ARGSUSED*/
|
|
boolean
|
|
bfd_generic_relax_section (abfd, section, link_info, again)
|
|
bfd *abfd;
|
|
asection *section;
|
|
struct bfd_link_info *link_info;
|
|
boolean *again;
|
|
{
|
|
*again = false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
INTERNAL_FUNCTION
|
|
bfd_generic_get_relocated_section_contents
|
|
|
|
SYNOPSIS
|
|
bfd_byte *
|
|
bfd_generic_get_relocated_section_contents (bfd *abfd,
|
|
struct bfd_link_info *link_info,
|
|
struct bfd_link_order *link_order,
|
|
bfd_byte *data,
|
|
boolean relocateable,
|
|
asymbol **symbols);
|
|
|
|
DESCRIPTION
|
|
Provides default handling of relocation effort for back ends
|
|
which can't be bothered to do it efficiently.
|
|
|
|
*/
|
|
|
|
bfd_byte *
|
|
bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data,
|
|
relocateable, symbols)
|
|
bfd *abfd;
|
|
struct bfd_link_info *link_info;
|
|
struct bfd_link_order *link_order;
|
|
bfd_byte *data;
|
|
boolean relocateable;
|
|
asymbol **symbols;
|
|
{
|
|
/* Get enough memory to hold the stuff */
|
|
bfd *input_bfd = link_order->u.indirect.section->owner;
|
|
asection *input_section = link_order->u.indirect.section;
|
|
|
|
long reloc_size = bfd_get_reloc_upper_bound (input_bfd, input_section);
|
|
arelent **reloc_vector = NULL;
|
|
long reloc_count;
|
|
|
|
if (reloc_size < 0)
|
|
goto error_return;
|
|
|
|
reloc_vector = (arelent **) malloc (reloc_size);
|
|
if (reloc_vector == NULL && reloc_size != 0)
|
|
{
|
|
bfd_set_error (bfd_error_no_memory);
|
|
goto error_return;
|
|
}
|
|
|
|
/* read in the section */
|
|
if (!bfd_get_section_contents (input_bfd,
|
|
input_section,
|
|
(PTR) data,
|
|
0,
|
|
input_section->_raw_size))
|
|
goto error_return;
|
|
|
|
/* We're not relaxing the section, so just copy the size info */
|
|
input_section->_cooked_size = input_section->_raw_size;
|
|
input_section->reloc_done = true;
|
|
|
|
reloc_count = bfd_canonicalize_reloc (input_bfd,
|
|
input_section,
|
|
reloc_vector,
|
|
symbols);
|
|
if (reloc_count < 0)
|
|
goto error_return;
|
|
|
|
if (reloc_count > 0)
|
|
{
|
|
arelent **parent;
|
|
for (parent = reloc_vector; *parent != (arelent *) NULL;
|
|
parent++)
|
|
{
|
|
char *error_message = (char *) NULL;
|
|
bfd_reloc_status_type r =
|
|
bfd_perform_relocation (input_bfd,
|
|
*parent,
|
|
(PTR) data,
|
|
input_section,
|
|
relocateable ? abfd : (bfd *) NULL,
|
|
&error_message);
|
|
|
|
if (relocateable)
|
|
{
|
|
asection *os = input_section->output_section;
|
|
|
|
/* A partial link, so keep the relocs */
|
|
os->orelocation[os->reloc_count] = *parent;
|
|
os->reloc_count++;
|
|
}
|
|
|
|
if (r != bfd_reloc_ok)
|
|
{
|
|
switch (r)
|
|
{
|
|
case bfd_reloc_undefined:
|
|
if (!((*link_info->callbacks->undefined_symbol)
|
|
(link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
|
|
input_bfd, input_section, (*parent)->address)))
|
|
goto error_return;
|
|
break;
|
|
case bfd_reloc_dangerous:
|
|
BFD_ASSERT (error_message != (char *) NULL);
|
|
if (!((*link_info->callbacks->reloc_dangerous)
|
|
(link_info, error_message, input_bfd, input_section,
|
|
(*parent)->address)))
|
|
goto error_return;
|
|
break;
|
|
case bfd_reloc_overflow:
|
|
if (!((*link_info->callbacks->reloc_overflow)
|
|
(link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
|
|
(*parent)->howto->name, (*parent)->addend,
|
|
input_bfd, input_section, (*parent)->address)))
|
|
goto error_return;
|
|
break;
|
|
case bfd_reloc_outofrange:
|
|
default:
|
|
abort ();
|
|
break;
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
if (reloc_vector != NULL)
|
|
free (reloc_vector);
|
|
return data;
|
|
|
|
error_return:
|
|
if (reloc_vector != NULL)
|
|
free (reloc_vector);
|
|
return NULL;
|
|
}
|