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/*

 * This file is a modified version of 'a.out.h'.  It is to be used in all

 * GNU tools modified to support the i80960 (or tools that operate on

 * object files created by such tools).

 *

 * All i80960 development is done in a CROSS-DEVELOPMENT environment.  I.e.,

 * object code is generated on, and executed under the direction of a symbolic

 * debugger running on, a host system.  We do not want to be subject to the

 * vagaries of which host it is or whether it supports COFF or a.out format,

 * or anything else.  We DO want to:

 *

 *      o always generate the same format object files, regardless of host.

 *

 *      o have an 'a.out' header that we can modify for our own purposes

 *        (the 80960 is typically an embedded processor and may require

 *        enhanced linker support that the normal a.out.h header can't

 *        accommodate).

 *

 * As for byte-ordering, the following rules apply:

 *

 *      o Text and data that is actually downloaded to the target is always

 *        in i80960 (little-endian) order.

 *

 *      o All other numbers (in the header, symbols, relocation directives)

 *        are in host byte-order:  object files CANNOT be lifted from a

 *        little-end host and used on a big-endian (or vice versa) without

 *        modification.

 * ==> THIS IS NO LONGER TRUE USING BFD.  WE CAN GENERATE ANY BYTE ORDER

 *     FOR THE HEADER, AND READ ANY BYTE ORDER.  PREFERENCE WOULD BE TO

 *     USE LITTLE-ENDIAN BYTE ORDER THROUGHOUT, REGARDLESS OF HOST.  <==

 *

 *      o The downloader ('comm960') takes care to generate a pseudo-header

 *        with correct (i80960) byte-ordering before shipping text and data

 *        off to the NINDY monitor in the target systems.  Symbols and

 *        relocation info are never sent to the target.

 */

#define BMAGIC  0415

/* We don't accept the following (see N_BADMAG macro).

 * They're just here so GNU code will compile.

 */

#define OMAGIC  0407            /* old impure format */

#define NMAGIC  0410            /* read-only text */

#define ZMAGIC  0413            /* demand load format */

/* FILE HEADER

 *      All 'lengths' are given as a number of bytes.

 *      All 'alignments' are for relinkable files only;  an alignment of

 *              'n' indicates the corresponding segment must begin at an

 *              address that is a multiple of (2**n).

 */

struct external_exec {

        /* Standard stuff */

        unsigned char e_info[4];        /* Identifies this as a b.out file */

        unsigned char e_text[4];        /* Length of text */

        unsigned char e_data[4];        /* Length of data */

        unsigned char e_bss[4];         /* Length of uninitialized data area */

        unsigned char e_syms[4];        /* Length of symbol table */

        unsigned char e_entry[4];       /* Runtime start address */

        unsigned char e_trsize[4];      /* Length of text relocation info */

        unsigned char e_drsize[4];      /* Length of data relocation info */

        /* Added for i960 */

        unsigned char e_tload[4];       /* Text runtime load address */

        unsigned char e_dload[4];       /* Data runtime load address */

        unsigned char e_talign[1];      /* Alignment of text segment */

        unsigned char e_dalign[1];      /* Alignment of data segment */

        unsigned char e_balign[1];      /* Alignment of bss segment */

        unsigned char e_relaxable[1];   /* Assembled with enough info to allow linker to relax */

};

#define EXEC_BYTES_SIZE (sizeof (struct external_exec))

/* These macros use the a_xxx field names, since they operate on the exec

   structure after it's been byte-swapped and realigned on the host machine. */

#define N_BADMAG(x)     (((x).a_info)!=BMAGIC)

#define N_TXTOFF(x)     EXEC_BYTES_SIZE

#define N_DATOFF(x)     ( N_TXTOFF(x) + (x).a_text )

#define N_TROFF(x)      ( N_DATOFF(x) + (x).a_data )

#define N_TRELOFF       N_TROFF

#define N_DROFF(x)      ( N_TROFF(x) + (x).a_trsize )

#define N_DRELOFF       N_DROFF

#define N_SYMOFF(x)     ( N_DROFF(x) + (x).a_drsize )

#define N_STROFF(x)     ( N_SYMOFF(x) + (x).a_syms )

#define N_DATADDR(x)    ( (x).a_dload )    

/* Address of text segment in memory after it is loaded.  */

#if !defined (N_TXTADDR)

#define N_TXTADDR(x) 0

#endif

/* A single entry in the symbol table

 */

struct nlist {

        union {

                char    *n_name;

                struct nlist *n_next;

                long    n_strx;         /* Index into string table      */

        } n_un;

        unsigned char n_type;   /* See below                            */

        char    n_other;        /* Used in i80960 support -- see below  */

        short   n_desc;

        unsigned long n_value;

};

/* Legal values of n_type

 */

#define N_UNDF  0        /* Undefined symbol     */

#define N_ABS   2       /* Absolute symbol      */

#define N_TEXT  4       /* Text symbol          */

#define N_DATA  6       /* Data symbol          */

#define N_BSS   8       /* BSS symbol           */

#define N_FN    31      /* Filename symbol      */

#define N_EXT   1       /* External symbol (OR'd in with one of above)  */

#define N_TYPE  036     /* Mask for all the type bits                   */

#define N_STAB  0340    /* Mask for all bits used for SDB entries       */

/* MEANING OF 'n_other'

 *

 * If non-zero, the 'n_other' fields indicates either a leaf procedure or

 * a system procedure, as follows:

 *

 *      1 <= n_other <= 32 :

 *              The symbol is the entry point to a system procedure.

 *              'n_value' is the address of the entry, as for any other

 *              procedure.  The system procedure number (which can be used in

 *              a 'calls' instruction) is (n_other-1).  These entries come from

 *              '.sysproc' directives.

 *

 *      n_other == N_CALLNAME

 *              the symbol is the 'call' entry point to a leaf procedure.

 *              The *next* symbol in the symbol table must be the corresponding

 *              'bal' entry point to the procedure (see following).  These

 *              entries come from '.leafproc' directives in which two different

 *              symbols are specified (the first one is represented here).

 *

 *

 *      n_other == N_BALNAME

 *              the symbol is the 'bal' entry point to a leaf procedure.

 *              These entries result from '.leafproc' directives in which only

 *              one symbol is specified, or in which the same symbol is

 *              specified twice.

 *

 * Note that an N_CALLNAME entry *must* have a corresponding N_BALNAME entry,

 * but not every N_BALNAME entry must have an N_CALLNAME entry.

 */

#define N_CALLNAME      ((char)-1)

#define N_BALNAME       ((char)-2)

#define IS_CALLNAME(x)  (N_CALLNAME == (x))

#define IS_BALNAME(x)   (N_BALNAME == (x))

#define IS_OTHER(x)     ((x)>0 && (x) <=32)

#define b_out_relocation_info relocation_info

struct relocation_info {

        int      r_address;     /* File address of item to be relocated */

        unsigned

#define r_index r_symbolnum

                r_symbolnum:24,/* Index of symbol on which relocation is based,

                                *       if r_extern is set.  Otherwise set to

                                *       either N_TEXT, N_DATA, or N_BSS to

                                *       indicate section on which relocation is

                                *       based.

                                */

                r_pcrel:1,      /* 1 => relocate PC-relative; else absolute

                                 *      On i960, pc-relative implies 24-bit

                                 *      address, absolute implies 32-bit.

                                 */

                r_length:2,     /* Number of bytes to relocate:

                                 *      0 => 1 byte

                                 *      1 => 2 bytes -- used for 13 bit pcrel

                                 *      2 => 4 bytes

                                 */

                r_extern:1,

                r_bsr:1,        /* Something for the GNU NS32K assembler */

                r_disp:1,       /* Something for the GNU NS32K assembler */

                r_callj:1,      /* 1 if relocation target is an i960 'callj' */

                r_relaxable:1;  /* 1 if enough info is left to relax

                                   the data */

};