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1172 lines
32 KiB
C
1172 lines
32 KiB
C
/* BFD support for handling relocation entries.
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Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
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Written by Cygnus Support.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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/*
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SECTION
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Relocations
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BFD maintains relocations in much the same was as it maintains
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symbols; they are left alone until required, then read in
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en-mass and traslated into an internal form. There is a common
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routine <<bfd_perform_relocation>> which acts upon the
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canonical form to to the actual fixup.
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Note that relocations are maintained on a per section basis,
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whilst symbols are maintained on a per BFD basis.
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All a back end has to do to fit the BFD interface is to create
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as many <<struct reloc_cache_entry>> as there are relocations
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in a particular section, and fill in the right bits:
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@menu
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@* typedef arelent::
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@* howto manager::
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@end menu
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*/
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#include "bfd.h"
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#include "sysdep.h"
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#include "libbfd.h"
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#include "seclet.h"
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/*
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DOCDD
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INODE
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typedef arelent, howto manager, Relocations, Relocations
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SUBSECTION
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typedef arelent
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This is the structure of a relocation entry:
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CODE_FRAGMENT
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.
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.typedef enum bfd_reloc_status
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.{
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. {* No errors detected *}
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. bfd_reloc_ok,
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.
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. {* The relocation was performed, but there was an overflow. *}
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. bfd_reloc_overflow,
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.
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. {* The address to relocate was not within the section supplied. *}
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. bfd_reloc_outofrange,
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.
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. {* Used by special functions *}
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. bfd_reloc_continue,
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.
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. {* Unused *}
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. bfd_reloc_notsupported,
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.
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. {* Unsupported relocation size requested. *}
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. bfd_reloc_other,
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.
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. {* The symbol to relocate against was undefined. *}
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. bfd_reloc_undefined,
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.
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. {* The relocation was performed, but may not be ok - presently
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. generated only when linking i960 coff files with i960 b.out
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. symbols. *}
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. bfd_reloc_dangerous
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. }
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. bfd_reloc_status_type;
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.
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.
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.typedef struct reloc_cache_entry
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.{
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. {* A pointer into the canonical table of pointers *}
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. struct symbol_cache_entry **sym_ptr_ptr;
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.
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. {* offset in section *}
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. bfd_size_type address;
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.
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. {* addend for relocation value *}
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. bfd_vma addend;
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.
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. {* Pointer to how to perform the required relocation *}
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. CONST struct reloc_howto_struct *howto;
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.
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.} arelent;
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*/
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/*
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DESCRIPTION
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Here is a description of each of the fields within a relent:
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o sym_ptr_ptr
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The symbol table pointer points to a pointer to the symbol
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associated with the relocation request. This would naturally
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be the pointer into the table returned by the back end's
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get_symtab action. @xref{Symbols}. The symbol is referenced
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through a pointer to a pointer so that tools like the linker
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can fix up all the symbols of the same name by modifying only
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one pointer. The relocation routine looks in the symbol and
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uses the base of the section the symbol is attached to and the
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value of the symbol as the initial relocation offset. If the
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symbol pointer is zero, then the section provided is looked up.
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o address
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The address field gives the offset in bytes from the base of
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the section data which owns the relocation record to the first
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byte of relocatable information. The actual data relocated
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will be relative to this point - for example, a relocation
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type which modifies the bottom two bytes of a four byte word
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would not touch the first byte pointed to in a big endian
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world.
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o addend
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The addend is a value provided by the back end to be added (!)
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to the relocation offset. Its interpretation is dependent upon
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the howto. For example, on the 68k the code:
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| char foo[];
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| main()
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| {
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| return foo[0x12345678];
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| }
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Could be compiled into:
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| linkw fp,#-4
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| moveb @@#12345678,d0
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| extbl d0
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| unlk fp
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| rts
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This could create a reloc pointing to foo, but leave the
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offset in the data (something like)
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|RELOCATION RECORDS FOR [.text]:
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|offset type value
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|00000006 32 _foo
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|00000000 4e56 fffc ; linkw fp,#-4
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|00000004 1039 1234 5678 ; moveb @@#12345678,d0
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|0000000a 49c0 ; extbl d0
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|0000000c 4e5e ; unlk fp
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|0000000e 4e75 ; rts
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Using coff and an 88k, some instructions don't have enough
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space in them to represent the full address range, and
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pointers have to be loaded in two parts. So you'd get something like:
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| or.u r13,r0,hi16(_foo+0x12345678)
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| ld.b r2,r13,lo16(_foo+0x12345678)
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| jmp r1
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This should create two relocs, both pointing to _foo, and with
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0x12340000 in their addend field. The data would consist of:
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|RELOCATION RECORDS FOR [.text]:
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|offset type value
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|00000002 HVRT16 _foo+0x12340000
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|00000006 LVRT16 _foo+0x12340000
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|00000000 5da05678 ; or.u r13,r0,0x5678
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|00000004 1c4d5678 ; ld.b r2,r13,0x5678
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|00000008 f400c001 ; jmp r1
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The relocation routine digs out the value from the data, adds
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it to the addend to get the original offset and then adds the
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value of _foo. Note that all 32 bits have to be kept around
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somewhere, to cope with carry from bit 15 to bit 16.
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One further example is the sparc and the a.out format. The
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sparc has a similar problem to the 88k, in that some
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instructions don't have room for an entire offset, but on the
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sparc the parts are created odd sized lumps. The designers of
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the a.out format chose not to use the data within the section
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for storing part of the offset; all the offset is kept within
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the reloc. Any thing in the data should be ignored.
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| save %sp,-112,%sp
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| sethi %hi(_foo+0x12345678),%g2
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| ldsb [%g2+%lo(_foo+0x12345678)],%i0
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| ret
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| restore
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Both relocs contains a pointer to foo, and the offsets would
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contain junk.
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|RELOCATION RECORDS FOR [.text]:
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|offset type value
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|00000004 HI22 _foo+0x12345678
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|00000008 LO10 _foo+0x12345678
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|00000000 9de3bf90 ; save %sp,-112,%sp
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|00000004 05000000 ; sethi %hi(_foo+0),%g2
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|00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0
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|0000000c 81c7e008 ; ret
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|00000010 81e80000 ; restore
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o howto
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The howto field can be imagined as a
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relocation instruction. It is a pointer to a struct which
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contains information on what to do with all the other
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information in the reloc record and data section. A back end
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would normally have a relocation instruction set and turn
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relocations into pointers to the correct structure on input -
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but it would be possible to create each howto field on demand.
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*/
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/*
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SUBSUBSECTION
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<<enum complain_overflow>>
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Indicates what sort of overflow checking should be done when
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performing a relocation.
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CODE_FRAGMENT
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.
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.enum complain_overflow
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.{
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. {* Do not complain on overflow. *}
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. complain_overflow_dont,
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.
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. {* Complain if the bitfield overflows, whether it is considered
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. as signed or unsigned. *}
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. complain_overflow_bitfield,
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.
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. {* Complain if the value overflows when considered as signed
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. number. *}
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. complain_overflow_signed,
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.
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. {* Complain if the value overflows when considered as an
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. unsigned number. *}
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. complain_overflow_unsigned
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.};
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*/
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/*
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SUBSUBSECTION
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<<reloc_howto_type>>
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The <<reloc_howto_type>> is a structure which contains all the
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information that BFD needs to know to tie up a back end's data.
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CODE_FRAGMENT
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.struct symbol_cache_entry; {* Forward declaration *}
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.
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.typedef CONST struct reloc_howto_struct
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.{
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. {* The type field has mainly a documetary use - the back end can
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. to what it wants with it, though the normally the back end's
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. external idea of what a reloc number would be would be stored
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. in this field. For example, the a PC relative word relocation
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. in a coff environment would have the type 023 - because that's
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. what the outside world calls a R_PCRWORD reloc. *}
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. unsigned int type;
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.
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. {* The value the final relocation is shifted right by. This drops
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. unwanted data from the relocation. *}
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. unsigned int rightshift;
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.
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. {* The size of the item to be relocated - 0, is one byte, 1 is 2
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. bytes, 2 is four bytes. A negative value indicates that the
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. result is to be subtracted from the data. *}
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. int size;
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.
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. {* The number of bits in the item to be relocated. This is used
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. when doing overflow checking. *}
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. unsigned int bitsize;
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.
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. {* Notes that the relocation is relative to the location in the
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. data section of the addend. The relocation function will
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. subtract from the relocation value the address of the location
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. being relocated. *}
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. boolean pc_relative;
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.
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. {* The bit position of the reloc value in the destination.
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. The relocated value is left shifted by this amount. *}
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. unsigned int bitpos;
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.
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. {* What type of overflow error should be checked for when
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. relocating. *}
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. enum complain_overflow complain_on_overflow;
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.
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. {* If this field is non null, then the supplied function is
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. called rather than the normal function. This allows really
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. strange relocation methods to be accomodated (e.g., i960 callj
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. instructions). *}
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. bfd_reloc_status_type (*special_function)
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. PARAMS ((bfd *abfd,
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. arelent *reloc_entry,
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. struct symbol_cache_entry *symbol,
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. PTR data,
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. asection *input_section,
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. bfd *output_bfd));
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.
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. {* The textual name of the relocation type. *}
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. char *name;
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.
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. {* When performing a partial link, some formats must modify the
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. relocations rather than the data - this flag signals this.*}
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. boolean partial_inplace;
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.
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. {* The src_mask is used to select what parts of the read in data
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. are to be used in the relocation sum. E.g., if this was an 8 bit
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. bit of data which we read and relocated, this would be
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. 0x000000ff. When we have relocs which have an addend, such as
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. sun4 extended relocs, the value in the offset part of a
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. relocating field is garbage so we never use it. In this case
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. the mask would be 0x00000000. *}
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. bfd_vma src_mask;
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.
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. {* The dst_mask is what parts of the instruction are replaced
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. into the instruction. In most cases src_mask == dst_mask,
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. except in the above special case, where dst_mask would be
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. 0x000000ff, and src_mask would be 0x00000000. *}
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. bfd_vma dst_mask;
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.
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. {* When some formats create PC relative instructions, they leave
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. the value of the pc of the place being relocated in the offset
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. slot of the instruction, so that a PC relative relocation can
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. be made just by adding in an ordinary offset (e.g., sun3 a.out).
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. Some formats leave the displacement part of an instruction
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. empty (e.g., m88k bcs), this flag signals the fact.*}
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. boolean pcrel_offset;
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.
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.} reloc_howto_type;
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*/
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/*
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FUNCTION
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the HOWTO macro
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DESCRIPTION
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The HOWTO define is horrible and will go away.
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.#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
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. {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
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DESCRIPTION
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And will be replaced with the totally magic way. But for the
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moment, we are compatible, so do it this way..
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.#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
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.
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DESCRIPTION
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Helper routine to turn a symbol into a relocation value.
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.#define HOWTO_PREPARE(relocation, symbol) \
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. { \
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. if (symbol != (asymbol *)NULL) { \
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. if (bfd_is_com_section (symbol->section)) { \
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. relocation = 0; \
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. } \
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. else { \
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. relocation = symbol->value; \
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. } \
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. } \
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.}
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*/
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/*
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TYPEDEF
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reloc_chain
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DESCRIPTION
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How relocs are tied together
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.typedef unsigned char bfd_byte;
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.
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.typedef struct relent_chain {
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. arelent relent;
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. struct relent_chain *next;
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.} arelent_chain;
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*/
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/*
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FUNCTION
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bfd_perform_relocation
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SYNOPSIS
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bfd_reloc_status_type
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bfd_perform_relocation
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(bfd * abfd,
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arelent *reloc_entry,
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PTR data,
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asection *input_section,
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bfd *output_bfd);
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DESCRIPTION
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If an output_bfd is supplied to this function the generated
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image will be relocatable, the relocations are copied to the
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output file after they have been changed to reflect the new
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state of the world. There are two ways of reflecting the
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results of partial linkage in an output file; by modifying the
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output data in place, and by modifying the relocation record.
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Some native formats (e.g., basic a.out and basic coff) have no
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way of specifying an addend in the relocation type, so the
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addend has to go in the output data. This is no big deal
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since in these formats the output data slot will always be big
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enough for the addend. Complex reloc types with addends were
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invented to solve just this problem.
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*/
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bfd_reloc_status_type
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DEFUN(bfd_perform_relocation,(abfd,
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reloc_entry,
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data,
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input_section,
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output_bfd),
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bfd *abfd AND
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arelent *reloc_entry AND
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PTR data AND
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asection *input_section AND
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bfd *output_bfd)
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{
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bfd_vma relocation;
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bfd_reloc_status_type flag = bfd_reloc_ok;
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bfd_size_type addr = reloc_entry->address ;
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bfd_vma output_base = 0;
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reloc_howto_type *howto = reloc_entry->howto;
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asection *reloc_target_output_section ;
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asymbol *symbol;
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symbol = *( reloc_entry->sym_ptr_ptr);
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if ((symbol->section == &bfd_abs_section)
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&& output_bfd != (bfd *)NULL)
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{
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reloc_entry->address += input_section->output_offset;
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return bfd_reloc_ok;
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}
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if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL)
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flag = bfd_reloc_undefined;
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/* If there is a function supplied to handle this relocation type,
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call it. It'll return `bfd_reloc_continue' if further processing
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can be done. */
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if (howto->special_function)
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{
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bfd_reloc_status_type cont;
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cont = howto->special_function (abfd, reloc_entry, symbol, data,
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input_section, output_bfd);
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if (cont != bfd_reloc_continue)
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return cont;
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}
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/* Is the address of the relocation really within the section? */
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if (reloc_entry->address > input_section->_cooked_size)
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return bfd_reloc_outofrange;
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/* Work out which section the relocation is targetted at and the
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initial relocation command value. */
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/* Get symbol value. (Common symbols are special.) */
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if (bfd_is_com_section (symbol->section))
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relocation = 0;
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else
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relocation = symbol->value;
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reloc_target_output_section = symbol->section->output_section;
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/* Convert input-section-relative symbol value to absolute. */
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if (output_bfd && howto->partial_inplace==false)
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output_base = 0;
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else
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output_base = reloc_target_output_section->vma;
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relocation += output_base + symbol->section->output_offset;
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/* Add in supplied addend. */
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relocation += reloc_entry->addend;
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if (howto->pc_relative == true)
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{
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/* Anything which started out as pc relative should end up that
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way too.
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There are two ways we can see a pcrel instruction. Sometimes
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the pcrel displacement has been partially calculated, it
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includes the distance from the start of the section to the
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instruction in it (e.g., sun3), and sometimes the field is
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totally blank - e.g., m88kbcs. */
|
|
|
|
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)
|
|
{
|
|
relocation -= reloc_entry->addend;
|
|
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. */
|
|
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))
|
|
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)
|
|
*/
|
|
relocation >>= howto->rightshift;
|
|
|
|
/* Shift everything up to where it's going to be used */
|
|
|
|
relocation <<= 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;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
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
|
|
|
|
CODE_FRAGMENT
|
|
.
|
|
.typedef enum bfd_reloc_code_real
|
|
.
|
|
.{
|
|
. {* 64 bits wide, simple reloc *}
|
|
. BFD_RELOC_64,
|
|
. {* 64 bits, PC-relative *}
|
|
. BFD_RELOC_64_PCREL,
|
|
.
|
|
. {* 32 bits wide, simple reloc *}
|
|
. BFD_RELOC_32,
|
|
. {* 32 bits, PC-relative *}
|
|
. BFD_RELOC_32_PCREL,
|
|
.
|
|
. {* 16 bits wide, simple reloc *}
|
|
. BFD_RELOC_16,
|
|
. {* 16 bits, PC-relative *}
|
|
. BFD_RELOC_16_PCREL,
|
|
.
|
|
. {* 8 bits wide, simple *}
|
|
. BFD_RELOC_8,
|
|
. {* 8 bits wide, pc relative *}
|
|
. BFD_RELOC_8_PCREL,
|
|
. {* 8 bits wide, but used to form an address like 0xffnn *}
|
|
. BFD_RELOC_8_FFnn,
|
|
.
|
|
. {* The type of reloc used to build a contructor table - at the
|
|
. moment probably a 32 bit wide abs address, but the cpu can
|
|
. choose. *}
|
|
.
|
|
. BFD_RELOC_CTOR,
|
|
.
|
|
. {* High 22 bits of 32-bit value; simple reloc. *}
|
|
. BFD_RELOC_HI22,
|
|
. {* Low 10 bits. *}
|
|
. BFD_RELOC_LO10,
|
|
.
|
|
. {* Reloc types used for i960/b.out. *}
|
|
. BFD_RELOC_24_PCREL,
|
|
. BFD_RELOC_I960_CALLJ,
|
|
.
|
|
. {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
|
|
. word displacement, e.g. for SPARC) *}
|
|
. BFD_RELOC_32_PCREL_S2,
|
|
.
|
|
. {* now for the sparc/elf codes *}
|
|
. BFD_RELOC_NONE, {* actually used *}
|
|
. BFD_RELOC_SPARC_WDISP22,
|
|
. BFD_RELOC_SPARC22,
|
|
. BFD_RELOC_SPARC13,
|
|
. BFD_RELOC_SPARC_GOT10,
|
|
. BFD_RELOC_SPARC_GOT13,
|
|
. BFD_RELOC_SPARC_GOT22,
|
|
. BFD_RELOC_SPARC_PC10,
|
|
. BFD_RELOC_SPARC_PC22,
|
|
. BFD_RELOC_SPARC_WPLT30,
|
|
. BFD_RELOC_SPARC_COPY,
|
|
. BFD_RELOC_SPARC_GLOB_DAT,
|
|
. BFD_RELOC_SPARC_JMP_SLOT,
|
|
. BFD_RELOC_SPARC_RELATIVE,
|
|
. BFD_RELOC_SPARC_UA32,
|
|
.
|
|
. {* this one is a.out specific? *}
|
|
. BFD_RELOC_SPARC_BASE13,
|
|
. BFD_RELOC_SPARC_BASE22,
|
|
.
|
|
. {* start-sanitize-v9 *}
|
|
. BFD_RELOC_SPARC_10,
|
|
. BFD_RELOC_SPARC_11,
|
|
.#define BFD_RELOC_SPARC_64 BFD_RELOC_64
|
|
. BFD_RELOC_SPARC_OLO10,
|
|
. BFD_RELOC_SPARC_HH22,
|
|
. BFD_RELOC_SPARC_HM10,
|
|
. BFD_RELOC_SPARC_LM22,
|
|
. BFD_RELOC_SPARC_PC_HH22,
|
|
. BFD_RELOC_SPARC_PC_HM10,
|
|
. BFD_RELOC_SPARC_PC_LM22,
|
|
. BFD_RELOC_SPARC_WDISP16,
|
|
. BFD_RELOC_SPARC_WDISP19,
|
|
. BFD_RELOC_SPARC_GLOB_JMP,
|
|
. BFD_RELOC_SPARC_LO7,
|
|
. {* end-sanitize-v9 *}
|
|
.
|
|
. {* Bits 27..2 of the relocation address shifted right 2 bits;
|
|
. simple reloc otherwise. *}
|
|
. BFD_RELOC_MIPS_JMP,
|
|
.
|
|
. {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
|
|
. BFD_RELOC_16_PCREL_S2,
|
|
.
|
|
. {* High 16 bits of 32-bit value; simple reloc. *}
|
|
. BFD_RELOC_HI16,
|
|
. {* 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. *}
|
|
. BFD_RELOC_HI16_S,
|
|
. {* Low 16 bits. *}
|
|
. BFD_RELOC_LO16,
|
|
.
|
|
. {* 16 bit relocation relative to the global pointer. *}
|
|
. BFD_RELOC_MIPS_GPREL,
|
|
.
|
|
. {* These are, so far, specific to HPPA processors. I'm not sure that
|
|
. some don't duplicate other reloc types, such as BFD_RELOC_32 and
|
|
. _32_PCREL. Also, many more were in the list I got that don't
|
|
. fit in well in the model BFD uses, so I've omitted them for now.
|
|
. If we do make this reloc type get used for code that really does
|
|
. implement the funky reloc types, they'll have to be added to this
|
|
. list. *}
|
|
. BFD_RELOC_HPPA_32,
|
|
. BFD_RELOC_HPPA_11,
|
|
. BFD_RELOC_HPPA_14,
|
|
. BFD_RELOC_HPPA_17,
|
|
. BFD_RELOC_HPPA_L21,
|
|
. BFD_RELOC_HPPA_R11,
|
|
. BFD_RELOC_HPPA_R14,
|
|
. BFD_RELOC_HPPA_R17,
|
|
. BFD_RELOC_HPPA_LS21,
|
|
. BFD_RELOC_HPPA_RS11,
|
|
. BFD_RELOC_HPPA_RS14,
|
|
. BFD_RELOC_HPPA_RS17,
|
|
. BFD_RELOC_HPPA_LD21,
|
|
. BFD_RELOC_HPPA_RD11,
|
|
. BFD_RELOC_HPPA_RD14,
|
|
. BFD_RELOC_HPPA_RD17,
|
|
. BFD_RELOC_HPPA_LR21,
|
|
. BFD_RELOC_HPPA_RR14,
|
|
. BFD_RELOC_HPPA_RR17,
|
|
. BFD_RELOC_HPPA_GOTOFF_11,
|
|
. BFD_RELOC_HPPA_GOTOFF_14,
|
|
. BFD_RELOC_HPPA_GOTOFF_L21,
|
|
. BFD_RELOC_HPPA_GOTOFF_R11,
|
|
. BFD_RELOC_HPPA_GOTOFF_R14,
|
|
. BFD_RELOC_HPPA_GOTOFF_LS21,
|
|
. BFD_RELOC_HPPA_GOTOFF_RS11,
|
|
. BFD_RELOC_HPPA_GOTOFF_RS14,
|
|
. BFD_RELOC_HPPA_GOTOFF_LD21,
|
|
. BFD_RELOC_HPPA_GOTOFF_RD11,
|
|
. BFD_RELOC_HPPA_GOTOFF_RD14,
|
|
. BFD_RELOC_HPPA_GOTOFF_LR21,
|
|
. BFD_RELOC_HPPA_GOTOFF_RR14,
|
|
. BFD_RELOC_HPPA_DLT_32,
|
|
. BFD_RELOC_HPPA_DLT_11,
|
|
. BFD_RELOC_HPPA_DLT_14,
|
|
. BFD_RELOC_HPPA_DLT_L21,
|
|
. BFD_RELOC_HPPA_DLT_R11,
|
|
. BFD_RELOC_HPPA_DLT_R14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_11,
|
|
. BFD_RELOC_HPPA_ABS_CALL_14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_17,
|
|
. BFD_RELOC_HPPA_ABS_CALL_L21,
|
|
. BFD_RELOC_HPPA_ABS_CALL_R11,
|
|
. BFD_RELOC_HPPA_ABS_CALL_R14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_R17,
|
|
. BFD_RELOC_HPPA_ABS_CALL_LS21,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RS11,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RS14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RS17,
|
|
. BFD_RELOC_HPPA_ABS_CALL_LD21,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RD11,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RD14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RD17,
|
|
. BFD_RELOC_HPPA_ABS_CALL_LR21,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RR14,
|
|
. BFD_RELOC_HPPA_ABS_CALL_RR17,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_11,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_12,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_14,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_17,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_L21,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_R11,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_R14,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_R17,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_LS21,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RS11,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RS14,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RS17,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_LD21,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RD11,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RD14,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RD17,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_LR21,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RR14,
|
|
. BFD_RELOC_HPPA_PCREL_CALL_RR17,
|
|
. BFD_RELOC_HPPA_PLABEL_32,
|
|
. BFD_RELOC_HPPA_PLABEL_11,
|
|
. BFD_RELOC_HPPA_PLABEL_14,
|
|
. BFD_RELOC_HPPA_PLABEL_L21,
|
|
. BFD_RELOC_HPPA_PLABEL_R11,
|
|
. BFD_RELOC_HPPA_PLABEL_R14,
|
|
. BFD_RELOC_HPPA_UNWIND_ENTRY,
|
|
. BFD_RELOC_HPPA_UNWIND_ENTRIES,
|
|
.
|
|
. {* this must be the highest numeric value *}
|
|
. BFD_RELOC_UNUSED
|
|
. } bfd_reloc_code_real_type;
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
SECTION
|
|
bfd_reloc_type_lookup
|
|
|
|
SYNOPSIS
|
|
CONST struct reloc_howto_struct *
|
|
bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
|
|
|
|
DESCRIPTION
|
|
This routine returns a pointer to a howto struct which when
|
|
invoked, will perform the supplied relocation on data from the
|
|
architecture noted.
|
|
|
|
*/
|
|
|
|
|
|
CONST struct reloc_howto_struct *
|
|
DEFUN(bfd_reloc_type_lookup,(abfd, code),
|
|
bfd *abfd AND
|
|
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
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SYNOPSIS
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CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
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(bfd *abfd AND
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bfd_reloc_code_real_type code);
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DESCRIPTION
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Provides a default relocation lookup routine for any architecture.
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*/
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CONST struct reloc_howto_struct *
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DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
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bfd *abfd AND
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bfd_reloc_code_real_type code)
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{
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switch (code)
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{
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case BFD_RELOC_CTOR:
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/* The type of reloc used in a ctor, which will be as wide as the
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address - so either a 64, 32, or 16 bitter.. */
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switch (bfd_get_arch_info (abfd)->bits_per_address) {
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case 64:
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BFD_FAIL();
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case 32:
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return &bfd_howto_32;
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case 16:
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BFD_FAIL();
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default:
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BFD_FAIL();
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}
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default:
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BFD_FAIL();
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}
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return (CONST struct reloc_howto_struct *)NULL;
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}
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/*
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INTERNAL_FUNCTION
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bfd_generic_relax_section
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SYNOPSIS
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boolean bfd_generic_relax_section
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(bfd *abfd,
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asection *section,
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asymbol **symbols);
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DESCRIPTION
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Provides default handling for relaxing for back ends which
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don't do relaxing -- i.e., does nothing.
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*/
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boolean
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DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
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bfd *abfd AND
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asection *section AND
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asymbol **symbols)
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{
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return false;
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}
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/*
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INTERNAL_FUNCTION
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bfd_generic_get_relocated_section_contents
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SYNOPSIS
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bfd_byte *
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bfd_generic_get_relocated_section_contents (bfd *abfd,
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struct bfd_seclet *seclet,
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bfd_byte *data,
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boolean relocateable);
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DESCRIPTION
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Provides default handling of relocation effort for back ends
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which can't be bothered to do it efficiently.
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*/
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bfd_byte *
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DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
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seclet,
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data,
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relocateable),
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bfd *abfd AND
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struct bfd_seclet *seclet AND
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bfd_byte *data AND
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boolean relocateable)
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{
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extern bfd_error_vector_type bfd_error_vector;
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/* Get enough memory to hold the stuff */
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bfd *input_bfd = seclet->u.indirect.section->owner;
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asection *input_section = seclet->u.indirect.section;
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size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
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arelent **reloc_vector = (arelent **) alloca(reloc_size);
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/* read in the section */
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bfd_get_section_contents(input_bfd,
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input_section,
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data,
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0,
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input_section->_raw_size);
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/* We're not relaxing the section, so just copy the size info */
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input_section->_cooked_size = input_section->_raw_size;
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input_section->reloc_done = true;
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if (bfd_canonicalize_reloc(input_bfd,
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input_section,
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reloc_vector,
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seclet->u.indirect.symbols) )
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{
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arelent **parent;
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for (parent = reloc_vector; * parent != (arelent *)NULL;
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parent++)
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{
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bfd_reloc_status_type r=
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bfd_perform_relocation(input_bfd,
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*parent,
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data,
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input_section,
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relocateable ? abfd : (bfd *) NULL);
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if (relocateable)
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{
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asection *os = input_section->output_section;
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/* A partial link, so keep the relocs */
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os->orelocation[os->reloc_count] = *parent;
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os->reloc_count++;
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}
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if (r != bfd_reloc_ok)
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{
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switch (r)
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{
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case bfd_reloc_undefined:
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bfd_error_vector.undefined_symbol(*parent, seclet);
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break;
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case bfd_reloc_dangerous:
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bfd_error_vector.reloc_dangerous(*parent, seclet);
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break;
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case bfd_reloc_outofrange:
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case bfd_reloc_overflow:
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bfd_error_vector.reloc_value_truncated(*parent, seclet);
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break;
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default:
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abort();
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break;
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}
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}
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}
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}
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return data;
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}
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