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5191 serge 1
/* This file is a modified version of 'a.out.h'.  It is to be used in all
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   GNU tools modified to support the i80960 (or tools that operate on
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   object files created by such tools).
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   Copyright (C) 2001-2015 Free Software Foundation, Inc.
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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 3 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., 51 Franklin Street - Fifth Floor, Boston,
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   MA 02110-1301, USA.  */
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/* All i80960 development is done in a CROSS-DEVELOPMENT environment.  I.e.,
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   object code is generated on, and executed under the direction of a symbolic
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   debugger running on, a host system.  We do not want to be subject to the
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   vagaries of which host it is or whether it supports COFF or a.out format,
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   or anything else.  We DO want to:
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  	o always generate the same format object files, regardless of host.
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 	o have an 'a.out' header that we can modify for our own purposes
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 	  (the 80960 is typically an embedded processor and may require
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 	  enhanced linker support that the normal a.out.h header can't
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 	  accommodate).
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  As for byte-ordering, the following rules apply:
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 	o Text and data that is actually downloaded to the target is always
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 	  in i80960 (little-endian) order.
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 	o All other numbers (in the header, symbols, relocation directives)
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 	  are in host byte-order:  object files CANNOT be lifted from a
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 	  little-end host and used on a big-endian (or vice versa) without
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 	  modification.
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  ==> THIS IS NO LONGER TRUE USING BFD.  WE CAN GENERATE ANY BYTE ORDER
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      FOR THE HEADER, AND READ ANY BYTE ORDER.  PREFERENCE WOULD BE TO
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      USE LITTLE-ENDIAN BYTE ORDER THROUGHOUT, REGARDLESS OF HOST.  <==
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 	o The downloader ('comm960') takes care to generate a pseudo-header
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 	  with correct (i80960) byte-ordering before shipping text and data
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 	  off to the NINDY monitor in the target systems.  Symbols and
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 	  relocation info are never sent to the target.  */
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#define BMAGIC	0415
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/* We don't accept the following (see N_BADMAG macro).
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   They're just here so GNU code will compile.  */
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#define	OMAGIC	0407		/* old impure format */
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#define	NMAGIC	0410		/* read-only text */
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#define	ZMAGIC	0413		/* demand load format */
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/* FILE HEADER
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  	All 'lengths' are given as a number of bytes.
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  	All 'alignments' are for relinkable files only;  an alignment of
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  		'n' indicates the corresponding segment must begin at an
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  		address that is a multiple of (2**n).  */
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struct external_exec
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  {
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    /* Standard stuff */
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    unsigned char e_info[4];	/* Identifies this as a b.out file */
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    unsigned char e_text[4];	/* Length of text */
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    unsigned char e_data[4];	/* Length of data */
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    unsigned char e_bss[4];	/* Length of uninitialized data area */
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    unsigned char e_syms[4];	/* Length of symbol table */
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    unsigned char e_entry[4];	/* Runtime start address */
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    unsigned char e_trsize[4];	/* Length of text relocation info */
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    unsigned char e_drsize[4];	/* Length of data relocation info */
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    /* Added for i960 */
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    unsigned char e_tload[4];	/* Text runtime load address */
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    unsigned char e_dload[4];	/* Data runtime load address */
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    unsigned char e_talign[1];	/* Alignment of text segment */
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    unsigned char e_dalign[1];	/* Alignment of data segment */
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    unsigned char e_balign[1];	/* Alignment of bss segment */
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    unsigned char e_relaxable[1];/* Assembled with enough info to allow linker to relax */
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  };
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#define	EXEC_BYTES_SIZE	(sizeof (struct external_exec))
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/* These macros use the a_xxx field names, since they operate on the exec
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   structure after it's been byte-swapped and realigned on the host machine.  */
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#define N_BADMAG(x)	(((x).a_info)!=BMAGIC)
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#define N_TXTOFF(x)	EXEC_BYTES_SIZE
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#define N_DATOFF(x)	( N_TXTOFF(x) + (x).a_text )
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#define N_TROFF(x)	( N_DATOFF(x) + (x).a_data )
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#define N_TRELOFF	N_TROFF
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#define N_DROFF(x)	( N_TROFF(x) + (x).a_trsize )
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#define N_DRELOFF	N_DROFF
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#define N_SYMOFF(x)	( N_DROFF(x) + (x).a_drsize )
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#define N_STROFF(x)	( N_SYMOFF(x) + (x).a_syms )
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#define N_DATADDR(x)	( (x).a_dload )
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/* Address of text segment in memory after it is loaded.  */
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#if !defined (N_TXTADDR)
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#define N_TXTADDR(x) 0
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#endif
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/* A single entry in the symbol table.  */
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struct nlist
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  {
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    union
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      {
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	char*          n_name;
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	struct nlist * n_next;
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	long	       n_strx;	/* Index into string table	*/
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      } n_un;
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    unsigned char n_type;	/* See below				*/
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    char	  n_other;	/* Used in i80960 support -- see below	*/
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    short	  n_desc;
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    unsigned long n_value;
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  };
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/* Legal values of n_type.  */
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#define N_UNDF	0	/* Undefined symbol	*/
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#define N_ABS	2	/* Absolute symbol	*/
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#define N_TEXT	4	/* Text symbol		*/
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#define N_DATA	6	/* Data symbol		*/
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#define N_BSS	8	/* BSS symbol		*/
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#define N_FN	31	/* Filename symbol	*/
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#define N_EXT	1	/* External symbol (OR'd in with one of above)	*/
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#define N_TYPE	036	/* Mask for all the type bits			*/
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#define N_STAB	0340	/* Mask for all bits used for SDB entries 	*/
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/* MEANING OF 'n_other'
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  If non-zero, the 'n_other' fields indicates either a leaf procedure or
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  a system procedure, as follows:
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 	1 <= n_other <= 32 :
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 		The symbol is the entry point to a system procedure.
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 		'n_value' is the address of the entry, as for any other
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 		procedure.  The system procedure number (which can be used in
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 		a 'calls' instruction) is (n_other-1).  These entries come from
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 		'.sysproc' directives.
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 	n_other == N_CALLNAME
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 		the symbol is the 'call' entry point to a leaf procedure.
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 		The *next* symbol in the symbol table must be the corresponding
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 		'bal' entry point to the procedure (see following).  These
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 		entries come from '.leafproc' directives in which two different
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 		symbols are specified (the first one is represented here).
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 	n_other == N_BALNAME
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 		the symbol is the 'bal' entry point to a leaf procedure.
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 		These entries result from '.leafproc' directives in which only
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 		one symbol is specified, or in which the same symbol is
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 		specified twice.
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  Note that an N_CALLNAME entry *must* have a corresponding N_BALNAME entry,
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  but not every N_BALNAME entry must have an N_CALLNAME entry.  */
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#define N_CALLNAME	((char)-1)
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#define N_BALNAME	((char)-2)
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#define IS_CALLNAME(x)	(N_CALLNAME == (x))
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#define IS_BALNAME(x)	(N_BALNAME == (x))
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#define IS_OTHER(x)	((x)>0 && (x) <=32)
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#define b_out_relocation_info relocation_info
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struct relocation_info
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  {
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    int	 r_address;	/* File address of item to be relocated.  */
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    unsigned
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#define r_index r_symbolnum
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    r_symbolnum:24,	/* Index of symbol on which relocation is based,
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			   if r_extern is set.  Otherwise set to
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			   either N_TEXT, N_DATA, or N_BSS to
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			   indicate section on which relocation is
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			   based.  */
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      r_pcrel:1,	/* 1 => relocate PC-relative; else absolute
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			   On i960, pc-relative implies 24-bit
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			   address, absolute implies 32-bit.  */
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      r_length:2,	/* Number of bytes to relocate:
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			   1 => 2 bytes -- used for 13 bit pcrel
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			   2 => 4 bytes.  */
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      r_extern:1,
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      r_bsr:1,		/* Something for the GNU NS32K assembler.  */
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      r_disp:1,		/* Something for the GNU NS32K assembler.  */
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      r_callj:1,	/* 1 if relocation target is an i960 'callj'.  */
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      r_relaxable:1;	/* 1 if enough info is left to relax the data.  */
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};