| /* Copyright 1992 Free Software Foundation, Inc. |
| * |
| * This file is a modified version of 'a.out.h'. It is to be used in all |
| * 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. |
| * |
| * 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 exec { |
| /* Standard stuff */ |
| unsigned long a_magic; /* Identifies this as a b.out file */ |
| unsigned long a_text; /* Length of text */ |
| unsigned long a_data; /* Length of data */ |
| unsigned long a_bss; /* Length of runtime uninitialized data area */ |
| unsigned long a_syms; /* Length of symbol table */ |
| unsigned long a_entry; /* Runtime start address */ |
| unsigned long a_trsize; /* Length of text relocation info */ |
| unsigned long a_drsize; /* Length of data relocation info */ |
| |
| /* Added for i960 */ |
| unsigned long a_tload; /* Text runtime load address */ |
| unsigned long a_dload; /* Data runtime load address */ |
| unsigned char a_talign; /* Alignment of text segment */ |
| unsigned char a_dalign; /* Alignment of data segment */ |
| unsigned char a_balign; /* Alignment of bss segment */ |
| unsigned char unused; /* (Just to make struct size a multiple of 4) */ |
| }; |
| |
| #define N_BADMAG(x) (((x).a_magic)!=BMAGIC) |
| #define N_TXTOFF(x) ( sizeof(struct exec) ) |
| #define N_DATOFF(x) ( N_TXTOFF(x) + (x).a_text ) |
| #define N_TROFF(x) ( N_DATOFF(x) + (x).a_data ) |
| #define N_DROFF(x) ( N_TROFF(x) + (x).a_trsize ) |
| #define N_SYMOFF(x) ( N_DROFF(x) + (x).a_drsize ) |
| #define N_STROFF(x) ( N_SYMOFF(x) + (x).a_syms ) |
| |
| /* 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 -1 |
| #define N_BALNAME -2 |
| |
| |
| struct relocation_info { |
| int r_address; /* File address of item to be relocated */ |
| unsigned |
| r_symbolnum:24,/* Index of symbol 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 |
| * 2 => 4 bytes -- only value used for i960 |
| */ |
| 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' */ |
| nuthin:1; /* Unused */ |
| }; |