ea8c7ac7d0
This is a greatly pared down version of the full gdb-4.12, all the config stuff has been removed and the supporting libraries have been stripped to a minimum. This is a 1.1.5 only port, I'll do a more complete port for 2.0 which will have all the config stuff and will install the gnu support libraries as system libraries like we do for readline. There wasn't much point for 1.1.5 since only gdb would use them so I went for saving space instead. For 2.0 I'll config all the other gnu tools to use them as well.
1226 lines
35 KiB
C
1226 lines
35 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 do 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. This is *not* a
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. power-of-two measure.
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. 0 : one byte
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. 1 : two bytes
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. 2 : four bytes
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. 3 : nothing done (unless special_function is nonzero)
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. 4 : eight bytes
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. -2 : two bytes, result should be subtracted from the
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. data instead of added
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. There is currently no trivial way to extract a "number of
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. bytes" from a howto pointer. *}
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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 we are not producing relocateable output, return an error if
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the symbol is not defined. An undefined weak symbol is
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considered to have a value of zero (SVR4 ABI, p. 4-27). */
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if (symbol->section == &bfd_und_section
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&& (symbol->flags & BSF_WEAK) == 0
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&& 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. */
|
|
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)
|
|
{
|
|
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.
|
|
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)
|
|
*/
|
|
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. 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.
|
|
|
|
CODE_FRAGMENT
|
|
.
|
|
.typedef enum bfd_reloc_code_real
|
|
.{
|
|
. {* Basic absolute relocations *}
|
|
. BFD_RELOC_64,
|
|
. BFD_RELOC_32,
|
|
. BFD_RELOC_16,
|
|
. BFD_RELOC_8,
|
|
.
|
|
. {* PC-relative relocations *}
|
|
. BFD_RELOC_64_PCREL,
|
|
. BFD_RELOC_32_PCREL,
|
|
. BFD_RELOC_24_PCREL, {* used by i960 *}
|
|
. BFD_RELOC_16_PCREL,
|
|
. BFD_RELOC_8_PCREL,
|
|
.
|
|
. {* Linkage-table relative *}
|
|
. BFD_RELOC_32_BASEREL,
|
|
. BFD_RELOC_16_BASEREL,
|
|
. BFD_RELOC_8_BASEREL,
|
|
.
|
|
. {* 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,
|
|
.
|
|
. {* 8 bits wide, but used to form an address like 0xffnn *}
|
|
. BFD_RELOC_8_FFnn,
|
|
.
|
|
. {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
|
|
. word displacement, e.g. for SPARC) *}
|
|
. BFD_RELOC_32_PCREL_S2,
|
|
.
|
|
. {* High 22 bits of 32-bit value, placed into lower 22 bits of
|
|
. target word; simple reloc. *}
|
|
. BFD_RELOC_HI22,
|
|
. {* Low 10 bits. *}
|
|
. BFD_RELOC_LO10,
|
|
.
|
|
. {* Reloc types used for i960/b.out. *}
|
|
. BFD_RELOC_I960_CALLJ,
|
|
.
|
|
. {* 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,
|
|
.
|
|
. {* these are a.out specific? *}
|
|
. BFD_RELOC_SPARC_BASE13,
|
|
. BFD_RELOC_SPARC_BASE22,
|
|
.
|
|
.
|
|
. {* 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,
|
|
.
|
|
. {* i386/elf relocations *}
|
|
. BFD_RELOC_386_GOT32,
|
|
. BFD_RELOC_386_PLT32,
|
|
. BFD_RELOC_386_COPY,
|
|
. BFD_RELOC_386_GLOB_DAT,
|
|
. BFD_RELOC_386_JUMP_SLOT,
|
|
. BFD_RELOC_386_RELATIVE,
|
|
. BFD_RELOC_386_GOTOFF,
|
|
. BFD_RELOC_386_GOTPC,
|
|
.
|
|
. {* 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
|
|
|
|
SYNOPSIS
|
|
CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
|
|
(bfd *abfd AND
|
|
bfd_reloc_code_real_type code);
|
|
|
|
DESCRIPTION
|
|
Provides a default relocation lookup routine for any architecture.
|
|
|
|
|
|
*/
|
|
|
|
CONST struct reloc_howto_struct *
|
|
DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
|
|
bfd *abfd AND
|
|
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;
|
|
}
|
|
|
|
|
|
/*
|
|
INTERNAL_FUNCTION
|
|
bfd_generic_relax_section
|
|
|
|
SYNOPSIS
|
|
boolean bfd_generic_relax_section
|
|
(bfd *abfd,
|
|
asection *section,
|
|
asymbol **symbols);
|
|
|
|
DESCRIPTION
|
|
Provides default handling for relaxing for back ends which
|
|
don't do relaxing -- i.e., does nothing.
|
|
*/
|
|
|
|
boolean
|
|
DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
|
|
bfd *abfd AND
|
|
asection *section AND
|
|
asymbol **symbols)
|
|
{
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
/*
|
|
INTERNAL_FUNCTION
|
|
bfd_generic_get_relocated_section_contents
|
|
|
|
SYNOPSIS
|
|
bfd_byte *
|
|
bfd_generic_get_relocated_section_contents (bfd *abfd,
|
|
struct bfd_seclet *seclet,
|
|
bfd_byte *data,
|
|
boolean relocateable);
|
|
|
|
DESCRIPTION
|
|
Provides default handling of relocation effort for back ends
|
|
which can't be bothered to do it efficiently.
|
|
|
|
*/
|
|
|
|
bfd_byte *
|
|
DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
|
|
seclet,
|
|
data,
|
|
relocateable),
|
|
bfd *abfd AND
|
|
struct bfd_seclet *seclet AND
|
|
bfd_byte *data AND
|
|
boolean relocateable)
|
|
{
|
|
extern bfd_error_vector_type bfd_error_vector;
|
|
|
|
/* Get enough memory to hold the stuff */
|
|
bfd *input_bfd = seclet->u.indirect.section->owner;
|
|
asection *input_section = seclet->u.indirect.section;
|
|
|
|
|
|
|
|
size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
|
|
arelent **reloc_vector = (arelent **) alloca(reloc_size);
|
|
|
|
/* read in the section */
|
|
bfd_get_section_contents(input_bfd,
|
|
input_section,
|
|
data,
|
|
0,
|
|
input_section->_raw_size);
|
|
|
|
/* 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;
|
|
|
|
|
|
if (bfd_canonicalize_reloc(input_bfd,
|
|
input_section,
|
|
reloc_vector,
|
|
seclet->u.indirect.symbols) )
|
|
{
|
|
arelent **parent;
|
|
for (parent = reloc_vector; * parent != (arelent *)NULL;
|
|
parent++)
|
|
{
|
|
bfd_reloc_status_type r=
|
|
bfd_perform_relocation(input_bfd,
|
|
*parent,
|
|
data,
|
|
input_section,
|
|
relocateable ? abfd : (bfd *) NULL);
|
|
|
|
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:
|
|
bfd_error_vector.undefined_symbol(*parent, seclet);
|
|
break;
|
|
case bfd_reloc_dangerous:
|
|
bfd_error_vector.reloc_dangerous(*parent, seclet);
|
|
break;
|
|
case bfd_reloc_outofrange:
|
|
case bfd_reloc_overflow:
|
|
bfd_error_vector.reloc_value_truncated(*parent, seclet);
|
|
break;
|
|
default:
|
|
abort();
|
|
break;
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
return data;
|
|
|
|
|
|
}
|